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Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Chemically reacting plumes, gas hydrate dissociation and dendrite solidification  

E-Print Network [OSTI]

II Gas hydrates Introductionto gas hydrates . . . . . . . . . . 1.127 Gas hydrate dissociation in porous media . 1.

Conroy, Devin Thomas

2008-01-01T23:59:59.000Z

2

Marine electromagnetic methods for gas hydrate characterization  

E-Print Network [OSTI]

1.2 Gas Hydrates . . . . . . . .1.2.1 Distribution of Gas Hydrates . . . . . . . . . . .1.2.2 Importance of Gas Hydrates . . . . .

Weitemeyer, Karen Andrea

2008-01-01T23:59:59.000Z

3

Marine Electromagnetic Methods for Gas Hydrate Characterization  

E-Print Network [OSTI]

1.2 Gas Hydrates . . . . . . . .1.2.1 Distribution of Gas Hydrates . . . . . . . . . . .1.2.2 Importance of Gas Hydrates . . . . .

Weitemeyer, Karen A

2008-01-01T23:59:59.000Z

4

Rapid gas hydrate formation process  

DOE Patents [OSTI]

The disclosure provides a method and apparatus for forming gas hydrates from a two-phase mixture of water and a hydrate forming gas. The two-phase mixture is created in a mixing zone which may be wholly included within the body of a spray nozzle. The two-phase mixture is subsequently sprayed into a reaction zone, where the reaction zone is under pressure and temperature conditions suitable for formation of the gas hydrate. The reaction zone pressure is less than the mixing zone pressure so that expansion of the hydrate-forming gas in the mixture provides a degree of cooling by the Joule-Thompson effect and provides more intimate mixing between the water and the hydrate-forming gas. The result of the process is the formation of gas hydrates continuously and with a greatly reduced induction time. An apparatus for conduct of the method is further provided.

Brown, Thomas D.; Taylor, Charles E.; Unione, Alfred J.

2013-01-15T23:59:59.000Z

5

Gas hydrate cool storage system  

DOE Patents [OSTI]

The invention presented relates to the development of a process utilizing a gas hydrate as a cool storage medium for alleviating electric load demands during peak usage periods. Several objectives of the invention are mentioned concerning the formation of the gas hydrate as storage material in a thermal energy storage system within a heat pump cycle system. The gas hydrate was formed using a refrigerant in water and an example with R-12 refrigerant is included. (BCS)

Ternes, M.P.; Kedl, R.J.

1984-09-12T23:59:59.000Z

6

Basin scale assessment of gas hydrate dissociation in response to climate change  

E-Print Network [OSTI]

Moridis GJ. Oceanic gas hydrate instability and dissociationKA. Potential effects of gas hydrate on human welfare, Proc.WS. A review of methane and gas hydrates in the dynamic,

Reagan, M.

2012-01-01T23:59:59.000Z

7

Modeling of Oceanic Gas Hydrate Instability and Methane Release in Response to Climate Change  

E-Print Network [OSTI]

Potential effects of gas hydrate on human welfare. Proc.W.S. A review of methane and gas hydrates in the dynamic,Geology of Natural Gas Hydrates, M. Max, A.H. Johnson, W.P.

Reagan, Matthew T.

2008-01-01T23:59:59.000Z

8

X-ray Scanner for ODP Leg 204: Drilling Gas Hydrates on Hydrate Ridge, Cascadia Continental Margin  

E-Print Network [OSTI]

International Conference of Gas Hydrates, Yokohama, Japan.Prospectus, Drilling Gas Hydrates On Hydrate Ridge, CascadiaLeg 204: Drilling Gas Hydrates on Hydrate Ridge, Cascadia

Freifeld, Barry; Kneafsey, Tim; Pruess, Jacob; Reiter, Paul; Tomutsa, Liviu

2002-01-01T23:59:59.000Z

9

Gas Hydrate Storage of Natural Gas  

SciTech Connect (OSTI)

Environmental and economic benefits could accrue from a safe, above-ground, natural-gas storage process allowing electric power plants to utilize natural gas for peak load demands; numerous other applications of a gas storage process exist. A laboratory study conducted in 1999 to determine the feasibility of a gas-hydrates storage process looked promising. The subsequent scale-up of the process was designed to preserve important features of the laboratory apparatus: (1) symmetry of hydrate accumulation, (2) favorable surface area to volume ratio, (3) heat exchanger surfaces serving as hydrate adsorption surfaces, (4) refrigeration system to remove heat liberated from bulk hydrate formation, (5) rapid hydrate formation in a non-stirred system, (6) hydrate self-packing, and (7) heat-exchanger/adsorption plates serving dual purposes to add or extract energy for hydrate formation or decomposition. The hydrate formation/storage/decomposition Proof-of-Concept (POC) pressure vessel and supporting equipment were designed, constructed, and tested. This final report details the design of the scaled POC gas-hydrate storage process, some comments on its fabrication and installation, checkout of the equipment, procedures for conducting the experimental tests, and the test results. The design, construction, and installation of the equipment were on budget target, as was the tests that were subsequently conducted. The budget proposed was met. The primary goal of storing 5000-scf of natural gas in the gas hydrates was exceeded in the final test, as 5289-scf of gas storage was achieved in 54.33 hours. After this 54.33-hour period, as pressure in the formation vessel declined, additional gas went into the hydrates until equilibrium pressure/temperature was reached, so that ultimately more than the 5289-scf storage was achieved. The time required to store the 5000-scf (48.1 hours of operating time) was longer than designed. The lower gas hydrate formation rate is attributed to a lower heat transfer rate in the internal heat exchanger than was designed. It is believed that the fins on the heat-exchanger tubes did not make proper contact with the tubes transporting the chilled glycol, and pairs of fins were too close for interior areas of fins to serve as hydrate collection sites. A correction of the fabrication fault in the heat exchanger fin attachments could be easily made to provide faster formation rates. The storage success with the POC process provides valuable information for making the process an economically viable process for safe, aboveground natural-gas storage.

Rudy Rogers; John Etheridge

2006-03-31T23:59:59.000Z

10

Strategies for gas production from oceanic Class 3 hydrate accumulations  

E-Print Network [OSTI]

coexistence of aqueous, gas and hydrate phases, indicatingIntrinsic Rate of Methane Gas Hydrate Decomposition”, Chem.Makogon, Y.F. , “Gas hydrates: frozen energy,” Recherche

Moridis, George J.; Reagan, Matthew T.

2007-01-01T23:59:59.000Z

11

Hydrates represent gas source, drilling hazard  

SciTech Connect (OSTI)

Gas hydrates look like ordinary ice. However, if a piece of such ice is put into warm water its behavior will be different from the ordinary melting of normal ice. In contrast, gas hydrates cause bubbles in the warm water, which indicates the high content of gas in the hydrate crystals. The presence of four components is required: gas itself, water, high pressure, and low temperature. The paper discusses how hydrates form, hydrates stability, South Caspian hydrates, and hydrates hazards for people, ships, pipelines, and drilling platforms.

Bagirov, E. [Azerbaijan Academy of Sciences, Baku (Azerbaijan); Lerche, I. [Univ. of South Carolina, Columbia, SC (United States)

1997-12-01T23:59:59.000Z

12

FROZEN HEAT A GLOBAL OUTLOOK ON METHANE GAS HYDRATES EXECUTIVE...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

About Gas Hydrates? What Role Do Gas Hydrates Play in Nature? Theme 2 Gas Hydrates as a Potential Energy Resource Are Gas Hydrates a Potential Energy Source? How Big Is the...

13

Challenges, uncertainties and issues facing gas production from gas hydrate deposits  

E-Print Network [OSTI]

of Gas Price ($/Mscf) for Offshore Gas Hydrate StudyEvaluation of deepwater gas-hydrate systems. The Leadingfor Gas Production from Gas Hydrates Reservoirs. J. Canadian

Moridis, G.J.

2011-01-01T23:59:59.000Z

14

High-pressure gas hydrates   

E-Print Network [OSTI]

It has long been known that crystalline hydrates are formed by many simple gases that do not interact strongly with water, and in most cases the gas molecules or atoms occupy 'cages' formed by a framework of water molecules. The majority...

Loveday, J. S.; Nelmes, R. J.

15

Gas hydrate reservoir characteristics and economics  

SciTech Connect (OSTI)

The primary objective of the DOE-funded USGS Gas Hydrate Program is to assess the production characteristics and economic potential of gas hydrates in northern Alaska. The objectives of this project for FY-1992 will include the following: (1) Utilize industry seismic data to assess the distribution of gas hydrates within the nearshore Alaskan continental shelf between Harrison Bay and Prudhoe Bay; (2) Further characterize and quantify the well-log characteristics of gas hydrates; and (3) Establish gas monitoring stations over the Eileen fault zone in northern Alaska, which will be used to measure gas flux from destabilized hydrates.

Collett, T.S.; Bird, K.J.; Burruss, R.C.; Lee, Myung W.

1992-01-01T23:59:59.000Z

16

Gas hydrate reservoir characteristics and economics  

SciTech Connect (OSTI)

The primary objective of the DOE-funded USGS Gas Hydrate Program is to assess the production characteristics and economic potential of gas hydrates in northern Alaska. The objectives of this project for FY-1992 will include the following: (1) Utilize industry seismic data to assess the distribution of gas hydrates within the nearshore Alaskan continental shelf between Harrison Bay and Prudhoe Bay; (2) Further characterize and quantify the well-log characteristics of gas hydrates; and (3) Establish gas monitoring stations over the Eileen fault zone in northern Alaska, which will be used to measure gas flux from destabilized hydrates.

Collett, T.S.; Bird, K.J.; Burruss, R.C.; Lee, Myung W.

1992-06-01T23:59:59.000Z

17

Gas hydrate cool storage system  

DOE Patents [OSTI]

This invention is a process for formation of a gas hydrate to be used as a cool storage medium using a refrigerant in water. Mixing of the immiscible refrigerant and water is effected by addition of a surfactant and agitation. The difficult problem of subcooling during the process is overcome by using the surfactant and agitation and performance of the process significantly improves and approaches ideal.

Ternes, Mark P. (Knoxville, TN); Kedl, Robert J. (Oak Ridge, TN)

1985-01-01T23:59:59.000Z

18

CONTENTS Concentrated Gas Hydrate  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New Substation Sites Proposed Route BTRICGEGR-N Goods PO 1 of 81,Concentrated Gas

19

Marine electromagnetic methods for gas hydrate characterization  

E-Print Network [OSTI]

to thank my advisor Professor Steven Constable for creatingDiego, 2008 Professor Steven Constable, Chair Gas hydrate isProfessor Professor Steven Constable, Chair Kevin Brown Je?

Weitemeyer, Karen Andrea

2008-01-01T23:59:59.000Z

20

Marine Electromagnetic Methods for Gas Hydrate Characterization  

E-Print Network [OSTI]

to thank my advisor Professor Steven Constable for creatingDiego, 2008 Professor Steven Constable, Chair Gas hydrate isProfessor Professor Steven Constable, Chair Kevin Brown Je?

Weitemeyer, Karen A

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Development of Alaskan gas hydrate resources  

SciTech Connect (OSTI)

The research undertaken in this project pertains to study of various techniques for production of natural gas from Alaskan gas hydrates such as, depressurization, injection of hot water, steam, brine, methanol and ethylene glycol solutions through experimental investigation of decomposition characteristics of hydrate cores. An experimental study has been conducted to measure the effective gas permeability changes as hydrates form in the sandpack and the results have been used to determine the reduction in the effective gas permeability of the sandpack as a function of hydrate saturation. A user friendly, interactive, menu-driven, numerical difference simulator has been developed to model the dissociation of natural gas hydrates in porous media with variable thermal properties. A numerical, finite element simulator has been developed to model the dissociation of hydrates during hot water injection process.

Kamath, V.A.; Sharma, G.D.; Patil, S.L.

1991-06-01T23:59:59.000Z

22

The Great Gas Hydrate Escape  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassiveSubmittedStatus TomAboutManusScience andFebruaryTheFarrel W.Great Gas Hydrate

23

Physical Properties of Gas Hydrates: A Review  

SciTech Connect (OSTI)

Methane gas hydrates in sediments have been studied by several investigators as a possible future energy resource. Recent hydrate reserves have been estimated at approximately 1016?m3 of methane gas worldwide at standard temperature and pressure conditions. In situ dissociation of natural gas hydrate is necessary in order to commercially exploit the resource from the natural-gas-hydrate-bearing sediment. The presence of gas hydrates in sediments dramatically alters some of the normal physical properties of the sediment. These changes can be detected by field measurements and by down-hole logs. An understanding of the physical properties of hydrate-bearing sediments is necessary for interpretation of geophysical data collected in field settings, borehole, and slope stability analyses; reservoir simulation; and production models. This work reviews information available in literature related to the physical properties of sediments containing gas hydrates. A brief review of the physical properties of bulk gas hydrates is included. Detection methods, morphology, and relevant physical properties of gas-hydrate-bearing sediments are also discussed.

Gabitto, Jorge [Prairie View A& M University; Tsouris, Costas [ORNL

2010-01-01T23:59:59.000Z

24

Gas Hydrates Research Programs: An International Review  

SciTech Connect (OSTI)

Gas hydrates sediments have the potential of providing a huge amount of natural gas for human use. Hydrate sediments have been found in many different regions where the required temperature and pressure conditions have been satisfied. Resource exploitation is related to the safe dissociation of the gas hydrate sediments. Basic depressurization techniques and thermal stimulation processes have been tried in pilot efforts to exploit the resource. There is a growing interest in gas hydrates all over the world due to the inevitable decline of oil and gas reserves. Many different countries are interested in this valuable resource. Unsurprisingly, developed countries with limited energy resources have taken the lead in worldwide gas hydrates research and exploration. The goal of this research project is to collect information in order to record and evaluate the relative strengths and goals of the different gas hydrates programs throughout the world. A thorough literature search about gas hydrates research activities has been conducted. The main participants in the research effort have been identified and summaries of their past and present activities reported. An evaluation section discussing present and future research activities has also been included.

Jorge Gabitto; Maria Barrufet

2009-12-09T23:59:59.000Z

25

Natural gas hydrates - issues for gas production and geomechanical stability  

E-Print Network [OSTI]

occurring at the field. Further, the controlling parameters for hydrate dissociation in porous media are quantified and a sensitivity study is presented. Chapter VI presents the results of a simulation experiment done to evaluate the performance of a..., the location iv of perforations and the gas hydrate saturation to be important parameters for gas production at the Messoyakha. Second, I simulated the gas production using a hydraulic fracture in hydrate bearing sediments. The simulation results showed...

Grover, Tarun

2008-10-10T23:59:59.000Z

26

Gas production potential of disperse low-saturation hydrate accumulations in oceanic sediments  

E-Print Network [OSTI]

EG. Formation of gas hydrates in natural gas transmissiongeology of natural gas hydrates. Amsterdam: Springer-Verlag;Soloviev, VA. Submarine gas hydrates. St. Petersburg;1998.

Moridis, George J.; Sloan, E. Dendy

2006-01-01T23:59:59.000Z

27

ConocoPhillips Gas Hydrate Production Test  

SciTech Connect (OSTI)

Work began on the ConocoPhillips Gas Hydrates Production Test (DOE award number DE-NT0006553) on October 1, 2008. This final report summarizes the entire project from January 1, 2011 to June 30, 2013.

Schoderbek, David; Farrell, Helen; Howard, James; Raterman, Kevin; Silpngarmlert, Suntichai; Martin, Kenneth; Smith, Bruce; Klein, Perry

2013-06-30T23:59:59.000Z

28

Modeling of gas hydrates from first principles  

E-Print Network [OSTI]

Ab initio calculations were used to determine the H20-CH4 potential energy surface (PES) accurately for use in modeling gas hydrates. Electron correlation was found to be treated accurately by the second-order Moller-Plesset ...

Cao, Zhitao, 1974-

2002-01-01T23:59:59.000Z

29

Detection of gas hydrates by the measurement of instantaneous temperature  

E-Print Network [OSTI]

Natural gas hydrates are icelike crystalline substances formed by gas molecules trapped in a water lattice. Suitable thermodynamic conditions and the presence of gas are required for the formation of natural gas hydrates in ocean sediments. Several...

Dinakaran, Srikanth

1994-01-01T23:59:59.000Z

30

Hydrate Control for Gas Storage Operations  

SciTech Connect (OSTI)

The overall objective of this project was to identify low cost hydrate control options to help mitigate and solve hydrate problems that occur in moderate and high pressure natural gas storage field operations. The study includes data on a number of flow configurations, fluids and control options that are common in natural gas storage field flow lines. The final phase of this work brings together data and experience from the hydrate flow test facility and multiple field and operator sources. It includes a compilation of basic information on operating conditions as well as candidate field separation options. Lastly the work is integrated with the work with the initial work to provide a comprehensive view of gas storage field hydrate control for field operations and storage field personnel.

Jeffrey Savidge

2008-10-31T23:59:59.000Z

31

Strategies for gas production from hydrate accumulations under various geologic conditions  

E-Print Network [OSTI]

JNOC/GSC Mallik 2L- 38 Gas Hydrate Research Well, Mackenziedeposits. INTRODUCTION Gas hydrates are solid crystallinequantity of hydrocarbon gas hydrates range between 10 15 to

Moridis, G.; Collett, T.

2003-01-01T23:59:59.000Z

32

Feasibility of monitoring gas hydrate production with time-lapse VSP  

E-Print Network [OSTI]

density of the aqueous, gas, and hydrate phases, which isfunction of the aqueous, gas and hydrate phase saturations;in Marine Sediments with Gas Hydrates: Effective Medium

Kowalsky, M.B.

2010-01-01T23:59:59.000Z

33

The effect of reservoir heterogeneity on gas production from hydrate accumulations in the permafrost  

E-Print Network [OSTI]

Spatial distributions of gas and hydrate phase saturations (from the Mallik 2002 Gas Hydrate Production Research Wellsimulating the behavior of gas hydrates, Energy Conversion

Reagan, M. T.

2010-01-01T23:59:59.000Z

34

Videos of Experiments from ORNL Gas Hydrate Research  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

Gas hydrate research performed by the Environmental Sciences Division utilizes the ORNL Seafloor Process Simulator, the Parr Vessel, the Sapphire Cell, a fiber optic distributed sensing system, and Raman spectroscopy. The group studies carbon sequestration in the ocean, desalination, gas hydrates in the solar system, and nucleation and dissociation kinetics. The videos available at the gas hydrates website are very short clips from experiments.

35

The goal of this work is to quantify the Van der Waals interactions in systems involving gas hydrates. Gas hydrates are crystalline com-  

E-Print Network [OSTI]

gas hydrates. Gas hydrates are crystalline com- pounds that are often encountered in oil and gas briefly present the hydrate crystalline structure and the role of hydrates in oil-and gas industry the industrial contexts where they appear, we shall cite : hydrate plugs obstructing oil- or gas

Boyer, Edmond

36

Numerical, Laboratory And Field Studies of Gas Production From Natural Hydrate Accumulations in Geologic Media  

E-Print Network [OSTI]

hydrate (Class 1W) or gas and hydrate (Class 1G). In Class 1Economic Geology of Natural Gas Hydrates, M. Max, A.H. John-of the thermal test of gas hydrate dissociation in the

Moridis, George J.; Kneafsey, Timothy J.; Kowalsky, Michael; Reagan, Matthew

2006-01-01T23:59:59.000Z

37

Depressurization-induced gas production from Class 1 and Class 2 hydrate deposits  

E-Print Network [OSTI]

hydrate (Class 1W) or gas and hydrate (Class 1G). In Class 1Class 1G (involving gas and hydrate in the HBL). In Class 2JNOC/GSC Mallik 2L-38 Gas Hydrate Research Well, Mackenzie

Moridis, George J.; Kowalsky, Michael

2006-01-01T23:59:59.000Z

38

Coupled multiphase fluid flow and wellbore stability analysis associated with gas production from oceanic hydrate-bearing sediments  

E-Print Network [OSTI]

Toward Production from Gas Hydrates: Current Status,Facing Gas Production From Gas-Hydrate Deposits. Society ofConference on Gas Hydrates (ICGH 2011), Edinburgh, Scotland,

Rutqvist, J.

2014-01-01T23:59:59.000Z

39

CONTENTS Gas Hydrate Assessment in  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New Substation Sites Proposed Route BTRICGEGR-N Goods PO 1 of 81,Concentrated GasGas

40

Oil and Gas CDT Gas hydrate distribution on tectonically active continental  

E-Print Network [OSTI]

Oil and Gas CDT Gas hydrate distribution on tectonically active continental margins: Impact on gas. Gregory F. Moore, University of Hawaii (USA) http://www.soest.hawaii.edu/moore/ Key Words Gas Hydrates, Faults, Fluid Flow, gas prospectivity Overview Fig. 1. Research on gas hydrates is often undertaken

Henderson, Gideon

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Gas hydrates in the Gulf of Mexico  

E-Print Network [OSTI]

filled by one or more gases. In marine sediments gas hydrates are found in regions where high pressure, low temperature and gas in excess of solubility are present. Low molecular weight hydrocarbons (LMWH), I. e. methane through butane, carbon dioxide... loop at a helium carrier flow of 12 ml/min with an elution order of methane, ethane, carbon dioxide and propane. Each fraction was trapped in a U- shaped Porpak-Q filled glass tube immersed in LN2. Butanes and heartier weight gases were trapped...

Cox, Henry Benjamin

1986-01-01T23:59:59.000Z

42

The Use of Horizontal Wells in Gas Production from Hydrate Accumulations  

E-Print Network [OSTI]

E.D. Toward Production From Gas Hydrates: Current Status,International Conference on Gas Hydrates, Trondheim, Norway,for Gas Production from Gas Hydrate Reservoirs, J. Can. Pet.

Moridis, George J.

2008-01-01T23:59:59.000Z

43

Comparison of Kinetic and Equilibrium Reaction Models in Simulating the Behavior of Gas Hydrates in Porous Media  

E-Print Network [OSTI]

rate constant of methane gas hydrate decomposition, CanadianAdvances in the Study of Gas Hydrates, C. Taylor , J. Qwan,International Conference on Gas Hydrates, Trondheim, Norway,

Kowalsky, Michael B.; Moridis, George J.

2006-01-01T23:59:59.000Z

44

Evaluation of the Gas Production Potential of Marine Hydrate Deposits in the Ulleung Basin of the Korean East Sea  

E-Print Network [OSTI]

indicators for natural gas hydrates in shallow sediments ofInternational Symposium on Gas Hydrate Technology, Seoul,International Symposium on Gas Hydrate Technology, Seoul,

Moridis, George J.; Reagan, Matthew T.; Kim, Se-Joon; Seol, Yongkoo; Zhang, Keni

2007-01-01T23:59:59.000Z

45

Numerical studies of gas production from several CH4-hydrate zones at the Mallik Site, Mackenzie Delta, Canada  

E-Print Network [OSTI]

JNOC/GSC Mallik 2L-38 Gas Hydrate Research Well, Mackenziepermafrost- associated gas hydrate accumulation in theTerritories, Canada. A gas hydrate research well was drilled

Moridis, George J.; Collett, Timothy S.; Dallimore, Scott R.; Satoh, Tohru; Hancock, Steven; Weatherill, Brian

2002-01-01T23:59:59.000Z

46

Rock-physics Models for Gas-hydrate Systems Associated  

E-Print Network [OSTI]

Rock-physics Models for Gas-hydrate Systems Associated with Unconsolidated Marine Sediments Diana associated with unconsolidated marine sediments. The goals are to predict gas-hydrate concentration from intercalated with unconsolidated sediments. We show that the geometrical details of how gas hy- drates

Texas at Austin, University of

47

Development of Alaskan gas hydrate resources. Final report  

SciTech Connect (OSTI)

The research undertaken in this project pertains to study of various techniques for production of natural gas from Alaskan gas hydrates such as, depressurization, injection of hot water, steam, brine, methanol and ethylene glycol solutions through experimental investigation of decomposition characteristics of hydrate cores. An experimental study has been conducted to measure the effective gas permeability changes as hydrates form in the sandpack and the results have been used to determine the reduction in the effective gas permeability of the sandpack as a function of hydrate saturation. A user friendly, interactive, menu-driven, numerical difference simulator has been developed to model the dissociation of natural gas hydrates in porous media with variable thermal properties. A numerical, finite element simulator has been developed to model the dissociation of hydrates during hot water injection process.

Kamath, V.A.; Sharma, G.D.; Patil, S.L.

1991-06-01T23:59:59.000Z

48

International Conference on Gas Hydrates May 19-23, 2002, Yokohama  

E-Print Network [OSTI]

4th International Conference on Gas Hydrates May 19-23, 2002, Yokohama Cold Flow Hydrate Technology an opportunity for flow assurance in deepwater production of oil and gas. Hydrate R&D in the Natural Gas Hydrate exchange and reactor units. Introduction Hydrates form when liquid water and natural gas are in contact

Gudmundsson, Jon Steinar

49

Occurrence of gas hydrate in Oligocene Frio sand: Alaminos Canyon Block 818: Northern Gulf of Mexico  

E-Print Network [OSTI]

Advances in the Study of Gas Hydrates. Kluwer, New York, pp.and quantification of gas hydrates using rock physics andand Salt Inhibition of Gas Hydrate Formation in the Northern

Boswell, R.D.

2010-01-01T23:59:59.000Z

50

Comparison of kinetic and equilibrium reaction models in simulating gas hydrate behavior in porous media  

E-Print Network [OSTI]

with Diapirism and Gas Hydrates at the Head of the Cape FearSea-Level Low Stands Above Gas Hydrate-Bearing Sediments.rate constant of methane gas hydrate decomposition. Canadian

Kowalsky, Michael B.; Moridis, George J.

2006-01-01T23:59:59.000Z

51

Geomechanical response of permafrost-associated hydrate deposits to depressurization-induced gas production  

E-Print Network [OSTI]

Conference on Gas Hydrates (ICGH 2008), Vancouver, BritishGSC et al. Mallik 5L-38 gas hydrate production research wellfrom the Mallik 2002 Gas Hydrate Production Research Well

Rutqvist, J.

2009-01-01T23:59:59.000Z

52

Sensitivity Analysis of Gas Production from Class 2 and Class 3 Hydrate Deposits  

E-Print Network [OSTI]

a) temperature, (b) gas and hydrate phase saturations, and (A Documented Example of Gas Hydrate Saturated Sand in theMakogon, Y.F. , “Gas hydrates: frozen energy,” Recherche 18(

Reagan, Matthew

2009-01-01T23:59:59.000Z

53

Contribution of oceanic gas hydrate dissociation to the formation of Arctic Ocean methane plumes  

E-Print Network [OSTI]

V.A. Soloviev, Submarine Gas Hydrates. St. Petersburg, 1998.and stability of gas hydrate-related bottom-simulatingPotential effects of gas hydrate on human welfare, Proc.

Reagan, M.

2012-01-01T23:59:59.000Z

54

Analysis of the Development of Messoyakha Gas Field: A Commercial Gas Hydrate Reservoir  

E-Print Network [OSTI]

the presence of gas hydrates in the Messoyakha field was not a certainty, this current study determined the undeniable presence of gas hydrates in the reservoir. This study uses four models of the Messoyakha field structure and reservoir conditions...

Omelchenko, Roman 1987-

2012-12-11T23:59:59.000Z

55

Surfactant process for promoting gas hydrate formation and application of the same  

DOE Patents [OSTI]

This invention relates to a method of storing gas using gas hydrates comprising forming gas hydrates in the presence of a water-surfactant solution that comprises water and surfactant. The addition of minor amounts of surfactant increases the gas hydrate formation rate, increases packing density of the solid hydrate mass and simplifies the formation-storage-decomposition process of gas hydrates. The minor amounts of surfactant also enhance the potential of gas hydrates for industrial storage applications.

Rogers, Rudy E. (Starkville, MS); Zhong, Yu (Brandon, MS)

2002-01-01T23:59:59.000Z

56

E-Print Network 3.0 - alaskan gas hydrate Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and finally the prospects for methane hydrates. NATURAL GAS AND THE RECOVERY PROCESS The primary... Coal Bed Methane Shale Gas Methane Hydrates Volume...

57

U N C L A S S I F I E D Gas Hydrate Experimental Capabilities at the Los Alamos  

E-Print Network [OSTI]

investigating synthesized (both in-situ and ex-situ) gas hydrates (methane, ethane, propane, CO2 and H2) using-host interactions that drive structure and dynamics. Lee et al., Science 2005 ·Storage of hydrogen in molecular form. ·Tetrahydrofuran (THF)-containing gas hydrate has been proposed as a storage material. THF + D2 clathrates

Downs, Robert T.

58

E ects of the Driving Force on the Composition of Natural Gas Hydrates  

E-Print Network [OSTI]

E ects of the Driving Force on the Composition of Natural Gas Hydrates Odd I. Levik(1) , Jean for storage and transport of natural gas. Storage of natural gas in the form of hydrate at elevated pressure concept) (Gud- mundsson et al. 1998). Natural gas hydrate contains up to 182 Sm3 gas per m3 hydrate

Gudmundsson, Jon Steinar

59

Gas hydrate research in the Gulf of Mexico: Final report  

SciTech Connect (OSTI)

The high energy seismic sections on the continental slope showed no evidence of a Bottom Simulating Reflector (BSR), which would indicate the presence of gas hydrates. There was no indication of metastable hydrates in continental shelf or slope sediments outside of the conventionally accepted temperature and pressure environment. Tracing the path of migrating gas from the source is much more straight forward than intercepting gas being transported and tracing it back to the source. Our study of low and medium energy seismic methods has shown that they could identify migrating gas. We feel strongly that there are hydrate zones in the Gulf of Mexico that are decomposing; they build up pressure and periodically release the trapped hydrocarbon gases. The released gases migrate vertically and/or laterally to mix with other types of gas or to form discrete pockets. Some of this gas may be emitted from underwater seeps into the overlying water column where it could be identified by a geochemical survey. The ratio of isobutane to normal butane determined by the geochemical survey can be used to assess the probability of the hydrocarbons emanating from a hydrate source. (The more the ratio exceeds 1.0 the greater the probability that the gas could be from a hydrate source.) As no indications of a hydrate zone (e.g., a BSR) were located, we were not able to establish a geophysical signature for gas hydrates; but the records indicate there are large volumes of gas migrating up the continental slope, some of which may have originated from a decomposing hydrate zone or from gas trapped below the hydrate cap. 20 refs., 13 figs., 1 tab.

Bennet, R.

1988-05-01T23:59:59.000Z

60

Handbook of gas hydrate properties and occurrence  

SciTech Connect (OSTI)

This handbook provides data on the resource potential of naturally occurring hydrates, the properties that are needed to evaluate their recovery, and their production potential. The first two chapters give data on the naturally occurring hydrate potential by reviewing published resource estimates and the known and inferred occurrences. The third and fourth chapters review the physical and thermodynamic properties of hydrates, respectively. The thermodynamic properties of hydrates that are discussed include dissociation energies and a simplified method to calculate them; phase diagrams for simple and multi-component gases; the thermal conductivity; and the kinetics of hydrate dissociation. The final chapter evaluates the net energy balance of recovering hydrates and shows that a substantial positive energy balance can theoretically be achieved. The Appendices of the Handbook summarize physical and thermodynamic properties of gases, liquids and solids that can be used in designing and evaluating recovery processes of hydrates. 158 references, 67 figures, 47 tables.

Kuustraa, V.A.; Hammershaimb, E.C.

1983-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

The dynamic response of oceanic hydrate deposits to ocean temperature change  

E-Print Network [OSTI]

Moridis, G.J. (2007), Oceanic gas hydrate instability andand salt inhibition of gas hydrate formation in the northernI.R. (1999), Thermogenic gas hydrates and hydrocarbon gases

Reagan, Matthew T.

2008-01-01T23:59:59.000Z

62

Drilling Through Gas Hydrates Formations: Managing Wellbore Stability Risks  

E-Print Network [OSTI]

As hydrocarbon exploration and development moves into deeper water and onshore arctic environments, it becomes increasingly important to quantify the drilling hazards posed by gas hydrates. To address these concerns, a 1D semi-analytical model...

Khabibullin, Tagir R.

2010-10-12T23:59:59.000Z

63

Drilling through gas hydrates formations: possible problems and suggested solution  

E-Print Network [OSTI]

Gas hydrate research in the last two decades has taken various directions ranging from ways to understand the safe and economical production of this enormous resource to drilling problems. as more rigs and production platforms move into deeper...

Amodu, Afolabi Ayoola

2009-05-15T23:59:59.000Z

64

An Integrated Study Method For Exploration Of Gas Hydrate Reservoirs...  

Open Energy Info (EERE)

approach for exploration of gas hydrate reservoirs in marine areas. Authors C. Y. Sun, B. H. Niu, P. F. Wen, Y. Y. Huang, H. Y. Wang, X. W. Huang and J. Li Published Journal...

65

Journal of Crystal Growth 243 (2002) 476489 Nucleation of gas hydrates  

E-Print Network [OSTI]

Journal of Crystal Growth 243 (2002) 476­489 Nucleation of gas hydrates Dimo Kashchieva , Abbas of nucleation of one-component gas hydrates in aqueous solutions are analyzed. The size of the hydrate nucleus. Nucleation; B1. Gas hydrates 1. Introduction Nucleation is perhaps the most challenging step in understanding

Firoozabadi, Abbas

66

Examination of core samples from the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope: Effects of retrieval and preservation  

E-Print Network [OSTI]

and handling of natural gas hydrate. GSC Bulletin, 544: 263-naturally occurring gas hydrates: the structures of methanefrom the Mount Elbert Gas Hydrate Stratigraphic Test Well,

Collett, T.J. Kneafsey, T.J., H. Liu, W. Winters, R. Boswell, R. Hunter, and T.S.

2012-01-01T23:59:59.000Z

67

Analysis of core samples from the BPXA-DOE-USGS Mount Elbert gas hydrate stratigraphic test well: Insights into core disturbance and handling  

E-Print Network [OSTI]

and handling of natural gas hydrate. GSC Bulletin, 544: 263-naturally occurring gas hydrates: the structures of methaneDOE-USGS Mount Elbert gas hydrate stratigraphic test well:

Kneafsey, Timothy J.

2010-01-01T23:59:59.000Z

68

Evaluation of a deposit in the vicinity of the PBU L-106 Site, North Slope, Alaska, for a potential long-term test of gas production from hydrates  

E-Print Network [OSTI]

of P, T, and gas and hydrate phase saturations (S G and SInternational Conference on Gas Hydrates, Vancouver, BritishM. 2008. Investigation of gas hydrate bearing sandstone

Moridis, G.J.

2010-01-01T23:59:59.000Z

69

Molecular dynamics simulation of hydration in myoglobin  

SciTech Connect (OSTI)

This study was carried out to evaluate the stability of the 89 bound water molecules that were observed in the neutron diffraction study of CO myoglobin. The myoglobin structure derived from the neutron analysis was used as the starting point in the molecular dynamics simulation using the software package CHARMM. After salvation of the protein, energy minimization and equilibration of the system, 50 pico seconds of Newtonian dynamics was performed. This data showed that only 4 water molecules are continously bound during the length of this simulation while the other solvent molecules exhibit considerable mobility and are breaking and reforming hydrogen bonds with the protein. At any instant during the simulation, 73 of the hydration sites observed in the neutron structure are occupied by water.

Gu, Wei [New Mexico Univ., Albuquerque, NM (United States). Dept. of Biochemistry; Schoenborn, B.P. [Los Alamos National Lab., NM (United States)

1995-09-01T23:59:59.000Z

70

Challenges, uncertainties and issues facing gas production from gas hydrate deposits  

SciTech Connect (OSTI)

The current paper complements the Moridis et al. (2009) review of the status of the effort toward commercial gas production from hydrates. We aim to describe the concept of the gas hydrate petroleum system, to discuss advances, requirement and suggested practices in gas hydrate (GH) prospecting and GH deposit characterization, and to review the associated technical, economic and environmental challenges and uncertainties, including: the accurate assessment of producible fractions of the GH resource, the development of methodologies for identifying suitable production targets, the sampling of hydrate-bearing sediments and sample analysis, the analysis and interpretation of geophysical surveys of GH reservoirs, well testing methods and interpretation of the results, geomechanical and reservoir/well stability concerns, well design, operation and installation, field operations and extending production beyond sand-dominated GH reservoirs, monitoring production and geomechanical stability, laboratory investigations, fundamental knowledge of hydrate behavior, the economics of commercial gas production from hydrates, and the associated environmental concerns.

Moridis, G.J.; Collett, T.S.; Pooladi-Darvish, M.; Hancock, S.; Santamarina, C.; Boswell, R.; Kneafsey, T.; Rutqvist, J.; Kowalsky, M.; Reagan, M.T.; Sloan, E.D.; Sum, A.K.; Koh, C.

2010-11-01T23:59:59.000Z

71

Marine electromagnetic methods for gas hydrate characterization  

E-Print Network [OSTI]

15 m 3 ) Conventional gas reserves Year of estimate Figureworld conventional gas reserves (from Milkov and Sassen (

Weitemeyer, Karen Andrea

2008-01-01T23:59:59.000Z

72

Marine Electromagnetic Methods for Gas Hydrate Characterization  

E-Print Network [OSTI]

15 m 3 ) Conventional gas reserves Year of estimate Figureworld conventional gas reserves (from Milkov and Sassen (

Weitemeyer, Karen A

2008-01-01T23:59:59.000Z

73

Hydration-dependent dynamics of deeply cooled water under strong confinement  

E-Print Network [OSTI]

We have measured the hydration-level dependence of the single-particle dynamics of water confined in the ordered mesoporous silica MCM-41. The dynamic crossover observed at full hydration is absent at monolayer hydration. ...

Bertrand, C. E.

74

Toward Production From Gas Hydrates: Current Status, Assessment of Resources, and Simulation-Based Evaluation of Technology and Potential  

E-Print Network [OSTI]

the second involves gas and hydrate (Class 1G, water-poorpriorities for marine gas hydrates, Fire In The Ice, NETLCollett, T. , 1993, Natural gas hydrates of the Prudhoe Bay

Moridis, George J.

2008-01-01T23:59:59.000Z

75

Numerical simulation studies of gas production scenarios from hydrate accumulations at the Mallik Site, McKenzie Delta, Canada  

E-Print Network [OSTI]

permafrost-associated gas hydrate accumulation in theCanada. An 1150 m deep gas hydrate research well was drilledscenarios from several gas-hydrate-bearing zones at the

Moridis, George J.; Collett, Timothy S.; Dallimore, Scott R.; Satoh, Tohru; Hancock, Stephen; Weatherhill, Brian

2002-01-01T23:59:59.000Z

76

Gas Production From a Cold, Stratigraphically Bounded Hydrate Deposit at the Mount Elbert Site, North Slope, Alaska  

E-Print Network [OSTI]

of P, T, and gas and hydrate phase saturations (S G and SJNOC/GSC Mallik 2L-38 Gas Hydrate Research-Well Sediments,interrelations relative to gas hydrates within the North

Moridis, G.J.

2010-01-01T23:59:59.000Z

77

Method and apparatus for recovering a gas from a gas hydrate located on the ocean floor  

DOE Patents [OSTI]

A method and apparatus for recovering a gas from a gas hydrate on the ocean floor includes a flexible cover, a plurality of steerable base members secured to the cover, and a steerable mining module. A suitable source for inflating the cover over the gas hydrate deposit is provided. The mining module, positioned on the gas hydrate deposit, is preferably connected to the cover by a control cable. A gas retrieval conduit or hose extends upwardly from the cover to be connected to a support ship on the ocean surface.

Wyatt, Douglas E. (Aiken, SC)

2001-01-01T23:59:59.000Z

78

Dynamical Transition and Heterogeneous Hydration Dynamics in RNA  

E-Print Network [OSTI]

Enhanced dynamical fluctuations of RNAs, facilitated by a network of water molecules with strong interactions with RNA, are suspected to be critical in their ability to respond to a variety of cellular signals. Using atomically detailed molecular dynamics simulations at various temperatures of purine (adenine)- and preQ$_1$ sensing riboswitch aptamers, we show that water molecules in the vicinity of RNAs undergo complex dynamics depending on the local structures of the RNAs. The overall lifetimes of hydrogen bonds (HBs) of surface bound waters are more than at least 1-2 orders of magnitude longer than bulk water. Slow hydration dynamics, revealed in non-Arrhenius behavior of the relaxation time, arises from high activation barriers to break water hydrogen bonds with a nucleotide and by reduced diffusion of water. The relaxation kinetics at specific locations in the two RNAs show a broad spectrum of time scales reminiscent of glass-like behavior, suggesting that the hydration dynamics is highly heterogeneous. Both RNAs undergo dynamic transition at $T = T_D \\gtrsim 200$ K as assessed by the mean square fluctuation of hydrogen atoms $\\langle x^2\\rangle$, which undergoes an abrupt harmonic-to-anharmonic transition at $T_D$. The near universal value of $T_D$ found for these RNAs and previously for tRNA is strongly correlated with changes in hydration dynamics as $T$ is altered. Hierarchical dynamics of waters associated with the RNA surface, revealed in the motions of distinct classes of water with well-separated time scales, reflects the heterogeneous local environment on the molecular surface of RNA. At low temperatures slow water dynamics predominates over structural transitions. Our study demonstrates that the complex interplay of dynamics between water and local environment in the RNA structures could be a key determinant of the functional activities of RNA.

Jeseong Yoon; Jong-Chin Lin; Changbong Hyeon; D. Thirumalai

2014-04-24T23:59:59.000Z

79

Detection of Gas Hydrates in Garden Banks and Keathley Canyon from Seismic Data  

E-Print Network [OSTI]

Gas hydrate is a potential energy source that has recently been the subject of much academic and industrial research. The search for deep-water gas hydrate involves many challenges that are especially apparent in the northwestern Gulf of Mexico...

Murad, Idris

2011-08-08T23:59:59.000Z

80

Site Selection for DOE/JIP Gas Hydrate Drilling in the Northern Gulf of Mexico  

SciTech Connect (OSTI)

Studies of geologic and geophysical data from the offshore of India have revealed two geologically distinct areas with inferred gas hydrate occurrences: the passive continental margins of the Indian Peninsula and along the Andaman convergent margin. The Indian National Gas Hydrate Program (NGHP) Expedition 01 was designed to study the occurrence of gas hydrate off the Indian Peninsula and along the Andaman convergent margin with special emphasis on understanding the geologic and geochemical controls on the occurrence of gas hydrate in these two diverse settings. NGHP Expedition 01 established the presence of gas hydrates in Krishna- Godavari, Mahanadi and Andaman basins. The expedition discovered one of the richest gas hydrate accumulations yet documented (Site 10 in the Krishna-Godavari Basin), documented the thickest and deepest gas hydrate stability zone yet known (Site 17 in Andaman Sea), and established the existence of a fully-developed gas hydrate system in the Mahanadi Basin (Site 19).

Collett, T.S. (USGS); Riedel, M. (McGill Univ., Montreal, Quebec, Canada); Cochran, J.R. (Columbia Univ., Palisades, NY); Boswell, R.M.; Kumar, Pushpendra (Oil and Natural Gas Corporation Ltd., Navi Mumbai, India); Sathe, A.V. (Oil and Natural Gas Corporation Ltd., Uttaranchal, INDIA)

2008-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Evaluation of the gas production economics of the gas hydrate cyclic thermal injection model  

SciTech Connect (OSTI)

The objective of the work performed under this directive is to assess whether gas hydrates could potentially be technically and economically recoverable. The technical potential and economics of recovering gas from a representative hydrate reservoir will be established using the cyclic thermal injection model, HYDMOD, appropriately modified for this effort, integrated with economics model for gas production on the North Slope of Alaska, and in the deep offshore Atlantic. The results from this effort are presented in this document. In Section 1, the engineering cost and financial analysis model used in performing the economic analysis of gas production from hydrates -- the Hydrates Gas Economics Model (HGEM) -- is described. Section 2 contains a users guide for HGEM. In Section 3, a preliminary economic assessment of the gas production economics of the gas hydrate cyclic thermal injection model is presented. Section 4 contains a summary critique of existing hydrate gas recovery models. Finally, Section 5 summarizes the model modification made to HYDMOD, the cyclic thermal injection model for hydrate gas recovery, in order to perform this analysis.

Kuuskraa, V.A.; Hammersheimb, E.; Sawyer, W.

1985-05-01T23:59:59.000Z

82

Mechanisms Leading to Co-Existence of Gas Hydrate in Ocean Sediments [Part 2 of 2  

SciTech Connect (OSTI)

In this project we have sought to explain the co-existence of gas and hydrate phases in sediments within the gas hydrate stability zone. We have focused on the gas/brine interface at the scale of individual grains in the sediment. The capillary forces associated with a gas/brine interface play a dominant role in many processes that occur in the pores of sediments and sedimentary rocks. The mechanical forces associated with the same interface can lead to fracture initiation and propagation in hydrate-bearing sediments. Thus the unifying theme of the research reported here is that pore scale phenomena are key to understanding large scale phenomena in hydrate-bearing sediments whenever a free gas phase is present. Our analysis of pore-scale phenomena in this project has delineated three regimes that govern processes in which the gas phase pressure is increasing: fracturing, capillary fingering and viscous fingering. These regimes are characterized by different morphology of the region invaded by the gas. On the other hand when the gas phase pressure is decreasing, the corresponding regimes are capillary fingering and compaction. In this project, we studied all these regimes except compaction. Many processes of interest in hydrate-bearing sediments can be better understood when placed in the context of the appropriate regime. For example, hydrate formation in sub-permafrost sediments falls in the capillary fingering regime, whereas gas invasion into ocean sediments is likely to fall into the fracturing regime. Our research provides insight into the mechanisms by which gas reservoirs are converted to hydrate as the base of the gas hydrate stability zone descends through the reservoir. If the reservoir was no longer being charged, then variation in grain size distribution within the reservoir explain hydrate saturation profiles such as that at Mt. Elbert, where sand-rich intervals containing little hydrate are interspersed between intervals containing large hydrate saturations. Large volumes (of order one pore volume) of gaseous and aqueous phases must be transported into the gas hydrate stability zone. The driver for this transport is the pressure sink induced by a reduction in occupied pore volume that accompanies the formation of hydrate from gas and water. Pore-scale imbibition models and bed-scale multiphase flow models indicate that the rate-limiting step in converting gas to hydrate is the supply of water to the hydrate stability zone. Moreover, the water supply rate is controlled by capillarity-driven flux for conditions typical of the Alaska North Slope. A meter-scale laboratory experiment confirms that significant volumes of fluid phases move into the hydrate stability zone and that capillarity is essential for the water flux. The model shows that without capillarity-driven flux, large saturations of hydrate cannot form. The observations of thick zones of large saturation at Mallik and Mt Elbert thus suggest that the primary control on these systems is the rate of transport of gaseous and aqueous phases, driven by the pressure sink at the base of the gas hydrate stability zone. A key finding of our project is the elucidation of ?capillary fracturing? as a dominant gas transport mechanism in low-permeability media. We initially investigate this phenomenon by means of grain-scale simulations in which we extended a discrete element mechanics code (PFC, by Itasca) to incorporate the dynamics of first singlephase and then multiphase flow. A reductionist model on a square lattice allows us to determine some of the fundamental dependencies of the mode of gas invasion (capillary fingering, viscous fingering, and fracturing) on the parameters of the system. We then show that the morphology of the gas-invaded region exerts a fundamental control on the fabric of methane hydrate formation, and on the overpressures caused by methane hydrate dissociation. We demonstrate the existence of the different invasion regimes by means of controlled laboratory experiments in a radial cell. We collapse the behavior in the form of a phase dia

Bryant, Steven; Juanes, Ruben

2011-12-31T23:59:59.000Z

83

Mechanisms Leading to Co-Existence of Gas Hydrate in Ocean Sediments [Part 1 of 2  

SciTech Connect (OSTI)

In this project we have sought to explain the co-existence of gas and hydrate phases in sediments within the gas hydrate stability zone. We have focused on the gas/brine interface at the scale of individual grains in the sediment. The capillary forces associated with a gas/brine interface play a dominant role in many processes that occur in the pores of sediments and sedimentary rocks. The mechanical forces associated with the same interface can lead to fracture initiation and propagation in hydrate-bearing sediments. Thus the unifying theme of the research reported here is that pore scale phenomena are key to understanding large scale phenomena in hydrate-bearing sediments whenever a free gas phase is present. Our analysis of pore-scale phenomena in this project has delineated three regimes that govern processes in which the gas phase pressure is increasing: fracturing, capillary fingering and viscous fingering. These regimes are characterized by different morphology of the region invaded by the gas. On the other hand when the gas phase pressure is decreasing, the corresponding regimes are capillary fingering and compaction. In this project, we studied all these regimes except compaction. Many processes of interest in hydrate-bearing sediments can be better understood when placed in the context of the appropriate regime. For example, hydrate formation in sub-permafrost sediments falls in the capillary fingering regime, whereas gas invasion into ocean sediments is likely to fall into the fracturing regime. Our research provides insight into the mechanisms by which gas reservoirs are converted to hydrate as the base of the gas hydrate stability zone descends through the reservoir. If the reservoir was no longer being charged, then variation in grain size distribution within the reservoir explain hydrate saturation profiles such as that at Mt. Elbert, where sand-rich intervals containing little hydrate are interspersed between intervals containing large hydrate saturations. Large volumes (of order one pore volume) of gaseous and aqueous phases must be transported into the gas hydrate stability zone. The driver for this transport is the pressure sink induced by a reduction in occupied pore volume that accompanies the formation of hydrate from gas and water. Pore-scale imbibition models and bed-scale multiphase flow models indicate that the rate-limiting step in converting gas to hydrate is the supply of water to the hydrate stability zone. Moreover, the water supply rate is controlled by capillarity-driven flux for conditions typical of the Alaska North Slope. A meter-scale laboratory experiment confirms that significant volumes of fluid phases move into the hydrate stability zone and that capillarity is essential for the water flux. The model shows that without capillarity-driven flux, large saturations of hydrate cannot form. The observations of thick zones of large saturation at Mallik and Mt Elbert thus suggest that the primary control on these systems is the rate of transport of gaseous and aqueous phases, driven by the pressure sink at the base of the gas hydrate stability zone. A key finding of our project is the elucidation of ?capillary fracturing? as a dominant gas transport mechanism in low-permeability media. We initially investigate this phenomenon by means of grain-scale simulations in which we extended a discrete element mechanics code (PFC, by Itasca) to incorporate the dynamics of first single-phase and then multiphase flow. A reductionist model on a square lattice allows us to determine some of the fundamental dependencies of the mode of gas invasion (capillary fingering, viscous fingering, and fracturing) on the parameters of the system. We then show that the morphology of the gas-invaded region exerts a fundamental control on the fabric of methane hydrate formation, and on the overpressures caused by methane hydrate dissociation. We demonstrate the existence of the different invasion regimes by means of controlled laboratory experiments in a radial cell. We collapse the behavior in the form of a phase di

Bryant, Steven; Juanes, Ruben

2011-12-31T23:59:59.000Z

84

Hydration dynamics near a model protein surface  

E-Print Network [OSTI]

AE, Onuchic JN. 2002. Protein folding mediated by solvation:of hydration forces in protein folding. Journal of Physicalthe broader context of protein folding and function and as

Russo, Daniela; Hura, Greg; Head-Gordon, Teresa

2003-01-01T23:59:59.000Z

85

International Conference on Gas Hydrates May 19-23, 2002, Yokohama  

E-Print Network [OSTI]

of hydrates for transport and storage of natural gas and in cold flow technology. In a continuous stirred tank. The same conditions are relevant in cold flow technology where oil, gas and water are passed through4th International Conference on Gas Hydrates May 19-23, 2002, Yokohama Hydrate Formation Rate

Gudmundsson, Jon Steinar

86

Natural Gas Hydrate Particles in Oil-Free Systems with Kinetic Inhibition and Slurry Viscosity Reduction  

E-Print Network [OSTI]

Natural Gas Hydrate Particles in Oil-Free Systems with Kinetic Inhibition and Slurry Viscosity, reduction of slurry viscosity, and corrosion inhibition. INTRODUCTION Water often forms gas hydrates antiagglomeration (AA) in the natural gas hydrate literature. The main limitation to application has been the need

Firoozabadi, Abbas

87

Application of the Cell Potential Method To Predict Phase Equilibria of Multicomponent Gas Hydrate Systems  

E-Print Network [OSTI]

Application of the Cell Potential Method To Predict Phase Equilibria of Multicomponent Gas Hydrate the first documentation nearly two centuries ago,2 natural gas clathrate-hydrates, called clathrates, have at understanding and avoiding clathrate formation. More recently, natural gas hydrates have been proposed

Bazant, Martin Z.

88

Acoustic and Thermal Characterization of Oil Migration, Gas Hydrates Formation and Silica Diagenesis  

E-Print Network [OSTI]

Acoustic and Thermal Characterization of Oil Migration, Gas Hydrates Formation and Silica Rights Reserved #12;ABSTRACT Acoustic and Thermal Characterization of Oil Migration, Gas Hydrates-A to Opal-CT, the formation of gas hydrates, fluid substitution in hydrocarbon reservoirs, and fluid

Guerin, Gilles

89

Coupled flow and geomechanical analysis for gas production in the Prudhoe Bay Unit L-106 well Unit C gas hydrate deposit in Alaska  

E-Print Network [OSTI]

2009. Toward Production From Gas Hydrates: Current Status,Geologic Controls on Gas Hydrate Occurrence in the MountCollett T.S. 1993. Natural Gas Hydrates of the Prudhoe Bay

Kim, J.

2014-01-01T23:59:59.000Z

90

Massive dissociation of gas hydrate during a Jurassic  

E-Print Network [OSTI]

release of methane from gas hydrate contained in marine continental-margin sediments. The better-known positive carbon-isotope excursion of the Early Toarcian is well illustrated by European organic-poor marine-resolution ammonite biostratigraphy is simply determined. Fossil wood is also present, preserved as coal (some

Hesselbo, Stephen P.

91

A Study of Formation and Dissociation of Gas Hydrate  

E-Print Network [OSTI]

and initial pressure. The aim of the second part of the study was the evaluation of the formation of gas hydrate and ice phases in a super-cooled methane-water system under the cooling rates of 0.45 and 0.6 degrees C/min, and the initial pressures of 1500...

Badakhshan Raz, Sadegh

2012-07-16T23:59:59.000Z

92

DOE Leads National Research Program in Gas Hydrates  

Broader source: Energy.gov [DOE]

The U.S. Department of Energy today told Congress the agency is leading a nationwide program in search of naturally occurring natural gas hydrates - a potentially significant storehouse of methane--with far reaching implications for the environment and the nation's future energy supplies.

93

Increasing gas hydrate formation temperature for desalination of high salinity produced water with secondary guests  

SciTech Connect (OSTI)

We suggest a new gas hydrate-based desalination process using water-immiscible hydrate formers; cyclopentane (CP) and cyclohexane (CH) as secondary hydrate guests to alleviate temperature requirements for hydrate formation. The hydrate formation reactions were carried out in an isobaric condition of 3.1 MPa to find the upper temperature limit of CO2 hydrate formation. Simulated produced water (8.95 wt % salinity) mixed with the hydrate formers shows an increased upper temperature limit from ?2 °C for simple CO2 hydrate to 16 and 7 °C for double (CO2 + CP) and (CO2 + CH) hydrates, respectively. The resulting conversion rate to double hydrate turned out to be similar to that with simple CO2 hydrate at the upper temperature limit. Hydrate formation rates (Rf) for the double hydrates with CP and CH are shown to be 22 and 16 times higher, respectively, than that of the simple CO2 hydrate at the upper temperature limit. Such mild hydrate formation temperature and fast formation kinetics indicate increased energy efficiency of the double hydrate system for the desalination process. Dissociated water from the hydrates shows greater than 90% salt removal efficiency for the hydrates with the secondary guests, which is also improved from about 70% salt removal efficiency for the simple hydrates.

Cha, Jong-Ho [ORISE; Seol, Yongkoo [U.S. DOE

2013-01-01T23:59:59.000Z

94

Gas Production from Hydrate-Bearing Sediments - Emergent Phenomena -  

SciTech Connect (OSTI)

Even a small fraction of fine particles can have a significant effect on gas production from hydrate-bearing sediments and sediment stability. Experiments were conducted to investigate the role of fine particles on gas production using a soil chamber that allows for the application of an effective stress to the sediment. This chamber was instrumented to monitor shear-wave velocity, temperature, pressure, and volume change during CO{sub 2} hydrate formation and gas production. The instrumented chamber was placed inside the Oak Ridge National Laboratory Seafloor Process Simulator (SPS), which was used to control the fluid pressure and temperature. Experiments were conducted with different sediment types and pressure-temperature histories. Fines migrated within the sediment in the direction of fluid flow. A vuggy structure formed in the sand; these small cavities or vuggs were precursors to the development of gas-driven fractures during depressurization under a constant effective stress boundary condition. We define the critical fines fraction as the clay-to-sand mass ratio when clays fill the pore space in the sand. Fines migration, clogging, vugs, and gas-driven fracture formation developed even when the fines content was significantly lower than the critical fines fraction. These results show the importance of fines in gas production from hydrate-bearing sediments, even when the fines content is relatively low.

Jung, J.W. [Georgia Institute of Technology; Jang, J.W. [Georgia Institute of Technology; Tsouris, Costas [ORNL; Phelps, Tommy Joe [ORNL; Rawn, Claudia J [ORNL; Santamarina, Carlos [Georgia Institute of Technology

2012-01-01T23:59:59.000Z

95

Seismic technology will be of key importance for evaluat-ing gas-hydrate resources, particularly across the Gulf of  

E-Print Network [OSTI]

Seismic technology will be of key importance for evaluat- ing gas-hydrate resources, particularly to be acquired. To apply seismic technology to gas-hydrate studies in the gulf in an optimal manner, it is essential to understand the seismic target that has to be analyzed. What is gas hydrate? Gas hydrate

Texas at Austin, University of

96

Hydration water dynamics and instigation of protein structuralrelaxation  

SciTech Connect (OSTI)

Until a critical hydration level is reached, proteins do not function. This critical level of hydration is analogous to a similar lack of protein function observed for temperatures below a dynamical temperature range of 180-220K that also is connected to the dynamics of protein surface water. Restoration of some enzymatic activity is observed in partially hydrated protein powders, sometimes corresponding to less than a single hydration layer on the protein surface, which indicates that the dynamical and structural properties of the surface water is intimately connected to protein stability and function. Many elegant studies using both experiment and simulation have contributed important information about protein hydration structure and timescales. The molecular mechanism of the solvent motion that is required to instigate the protein structural relaxation above a critical hydration level or transition temperature has yet to be determined. In this work we use experimental quasi-elastic neutron scattering (QENS) and molecular dynamics simulation to investigate hydration water dynamics near a greatly simplified protein system. We consider the hydration water dynamics near the completely deuterated N-acetyl-leucine-methylamide (NALMA) solute, a hydrophobic amino acid side chain attached to a polar blocked polypeptide backbone, as a function of concentration between 0.5M-2.0M under ambient conditions. We note that roughly 50-60% of a folded protein's surface is equally distributed between hydrophobic and hydrophilic domains, domains whose lengths are on the order of a few water diameters, that justify our study of hydration dynamics of this simple model protein system. The QENS experiment was performed at the NIST Center for Neutron Research, using the disk chopper time of flight spectrometer (DCS). In order to separate the translational and rotational components in the spectra, two sets of experiments were carried out using different incident neutron wavelengths of 7.5{angstrom} and 5.5{angstrom} to give two different time resolutions. All the spectra have been measure at room temperature. The spectra were corrected for the sample holder contribution and normalized using the vanadium standard. The resulting data were analyzed with DAVE programs (http://www.ncnr.nist.gov/dave/). The AMBER force field and SPCE water model were used for modeling the NALMA solute and water, respectively. For the analysis of the water dynamics in the NALMA aqueous solutions, we performed simulations of a dispersed solute configuration consistent with our previous structural analysis, where we had primarily focused on the structural organization of these peptide solutions and their connection to protein folding. Further details of the QENS experiment and molecular dynamics simulations are reported elsewhere.

Russo, Daniela; Hura, Greg; Head-Gordon, Teresa

2003-09-01T23:59:59.000Z

97

Effects of hydration water on protein methyl group dynamics insolution  

SciTech Connect (OSTI)

Elastic and quasielastic neutron scattering experiments have been used to investigate the dynamics of methyl groups in a protein-model hydrophobic peptide in solution. The results suggest that, when the hydrophobic side chains are hydrated by a single hydration water layer, the only allowed motions are confined and attributed to librational and rotational movement associated with the methyl groups. They provide unique experimental evidence that the structural and dynamical properties of the interfacial water strongly influence the side-chain dynamics and the activation of diffusive motion.

Russo D; Hura GL; Copley JRD

2007-01-01T23:59:59.000Z

98

X-ray CT Observations of Methane Hydrate Distribution Changes over Time in a Natural Sediment Core from the BPX-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well  

E-Print Network [OSTI]

and Englezos, P. , 2009. Gas hydrate formation in a variableDOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test WellFormation of natural gas hydrates in marine sediments. 1.

Kneafsey, T.J.

2012-01-01T23:59:59.000Z

99

Journal of Crystal Growth 250 (2003) 499515 Induction time in crystallization of gas hydrates  

E-Print Network [OSTI]

. Kern Abstract The kinetics of the initial stage of crystallization of one-component gas hydrates. Kinetic inhibitors 1. Introduction In natural gas production, both gas and aqu- eous phases are usually is relatively low (less than 1 wt%). In thermodynamic inhibition, the gas­water­hydrate equilibrium curve

Firoozabadi, Abbas

100

Dynamics of lysozyme and its hydration water under electric field  

SciTech Connect (OSTI)

The effects of static electric field on the dynamics of lysozyme and its hydration water have been investigated by means of incoherent quasi-elastic neutron scattering (QENS). Measurements were performed on lysozyme samples, hydrated respectively with heavy water (D2O) to capture the protein dynamics, and with light water (H2O), to probe the dynamics of the hydration shell, in the temperature range from 210 < T < 260 K. The hydration fraction in both cases was about 0.38 gram of water per gram of dry protein. The field strengths investigated were respectively 0 kV/mm and 2 kV/mm ( 2 106 V/m) for the protein hydrated with D2O and 0 kV and 1 kV/mm for the H2O-hydrated counterpart. While the overall internal protons dynamics of the protein appears to be unaffected by the application of electric field up to 2 kV/mm, likely due to the stronger intra-molecular interactions, there is also no appreciable quantitative enhancement of the diffusive dynamics of the hydration water, as would be anticipated based on our recent observations in water confined in silica pores under field values of 2.5 kV/mm. This may be due to the difference in surface interactions between water and the two adsorption hosts (silica and protein), or to the existence of a critical threshold field value Ec 2 3 kV/mm for increased molecular diffusion, for which electrical breakdown is a limitation for our sample.

Favi, Pelagie M [ORNL; Zhang, Qiu [ORNL; O'Neill, Hugh Michael [ORNL; Mamontov, Eugene [ORNL; Omar Diallo, Souleymane [ORNL; Palmer, Jeremy [North Carolina State University

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Clathrate hydrate equilibrium data for the gas mixture of carbon dioxide and nitrogen in the  

E-Print Network [OSTI]

1 Clathrate hydrate equilibrium data for the gas mixture of carbon dioxide and nitrogen the mole fraction of CO2 in the carbon dioxide + nitrogen + cyclopentane mixed hydrate phase, both defined;2 {water +carbon dioxide + nitrogen}, the equilibrium pressure of the mixed hydrate is reduced by 0.95 up

Paris-Sud XI, Université de

102

Using Carbon Dioxide to Enhance Recovery of Methane from Gas Hydrate Reservoirs: Final Summary Report  

SciTech Connect (OSTI)

Carbon dioxide sequestration coupled with hydrocarbon resource recovery is often economically attractive. Use of CO2 for enhanced recovery of oil, conventional natural gas, and coal-bed methane are in various stages of common practice. In this report, we discuss a new technique utilizing CO2 for enhanced recovery of an unconventional but potentially very important source of natural gas, gas hydrate. We have focused our attention on the Alaska North Slope where approximately 640 Tcf of natural gas reserves in the form of gas hydrate have been identified. Alaska is also unique in that potential future CO2 sources are nearby, and petroleum infrastructure exists or is being planned that could bring the produced gas to market or for use locally. The EGHR (Enhanced Gas Hydrate Recovery) concept takes advantage of the physical and thermodynamic properties of mixtures in the H2O-CO2 system combined with controlled multiphase flow, heat, and mass transport processes in hydrate-bearing porous media. A chemical-free method is used to deliver a LCO2-Lw microemulsion into the gas hydrate bearing porous medium. The microemulsion is injected at a temperature higher than the stability point of methane hydrate, which upon contacting the methane hydrate decomposes its crystalline lattice and releases the enclathrated gas. Small scale column experiments show injection of the emulsion into a CH4 hydrate rich sand results in the release of CH4 gas and the formation of CO2 hydrate

McGrail, B. Peter; Schaef, Herbert T.; White, Mark D.; Zhu, Tao; Kulkarni, Abhijeet S.; Hunter, Robert B.; Patil, Shirish L.; Owen, Antionette T.; Martin, P F.

2007-09-01T23:59:59.000Z

103

Dynamics of biopolymers and their hydration water studied by neutron and X-ray scattering  

E-Print Network [OSTI]

Protein functions are intimately related to their dynamics. Moreover, protein hydration water is believed to have significant influence on the dynamics of proteins. One of the evidence is that both protein and its hydration ...

Chu, Xiang-qiang

2010-01-01T23:59:59.000Z

104

Estimating the upper limit of gas production from Class 2 hydrate accumulations in the permafrost: 2. Alternative well designs and sensitivity analysis  

E-Print Network [OSTI]

m). As in all cases of gas hydrates (Moridis et al. , 2007;by destroying the secondary gas hydrate barrier (if such aInduced Gas Production From Class 1 Hydrate Deposits,” SPE

Moridis, G.

2011-01-01T23:59:59.000Z

105

Estimation of methane flux offshore SW Taiwan and the influence of tectonics on gas hydrate accumulation  

E-Print Network [OSTI]

Estimation of methane flux offshore SW Taiwan and the influence of tectonics on gas hydrate simulating reflectors (BSRs) imply the potential existence of gas hydrates offshore southwestern Taiwan that the fluxes are very high in offshore southwestern Taiwan. The depths of the SMI are different at sites GH6

Lin, Andrew Tien-Shun

106

AGGLOMERATION OF GAS HYDRATE IN A WATER-IN-OIL EMULSION: EXPERIMENTAL AND MODELING STUDIES  

E-Print Network [OSTI]

AGGLOMERATION OF GAS HYDRATE IN A WATER-IN-OIL EMULSION: EXPERIMENTAL AND MODELING STUDIES Ana of gas hydrates in water-in-oil emulsion is investigated at the laboratory pilot scale on a flow loop, rheology, chord length distribution, modeling Corresponding author: Phone: +33 477420286 Fax +33 477429694

Paris-Sud XI, Université de

107

Site Selection for DOE/JIP Gas Hydrate Drilling in the Northern Gulf of Mexico  

SciTech Connect (OSTI)

In the late spring of 2008, the Chevron-led Gulf of Mexico Gas Hydrate Joint Industry Project (JIP) expects to conduct an exploratory drilling and logging campaign to better understand gas hydrate-bearing sands in the deepwater Gulf of Mexico. The JIP Site Selection team selected three areas to test alternative geological models and geophysical interpretations supporting the existence of potential high gas hydrate saturations in reservoir-quality sands. The three sites are near existing drill holes which provide geological and geophysical constraints in Alaminos Canyon (AC) lease block 818, Green Canyon (GC) 955, and Walker Ridge (WR) 313. At the AC818 site, gas hydrate is interpreted to occur within the Oligocene Frio volcaniclastic sand at the crest of a fold that is shallow enough to be in the hydrate stability zone. Drilling at GC955 will sample a faulted, buried Pleistocene channel-levee system in an area characterized by seafloor fluid expulsion features, structural closure associated with uplifted salt, and abundant seismic evidence for upward migration of fluids and gas into the sand-rich parts of the sedimentary section. Drilling at WR313 targets ponded sheet sands and associated channel/levee deposits within a minibasin, making this a non-structural play. The potential for gas hydrate occurrence at WR313 is supported by shingled phase reversals consistent with the transition from gas-charged sand to overlying gas-hydrate saturated sand. Drilling locations have been selected at each site to 1) test geological methods and models used to infer the occurrence of gas hydrate in sand reservoirs in different settings in the northern Gulf of Mexico; 2) calibrate geophysical models used to detect gas hydrate sands, map reservoir thicknesses, and estimate the degree of gas hydrate saturation; and 3) delineate potential locations for subsequent JIP drilling and coring operations that will collect samples for comprehensive physical property, geochemical and other analyses.

Hutchinson, D.R. (USGS); Shelander, D. (Schlumberger, Houston, TX); Dai, J. (Schlumberger, Hoston, TX); McConnell, D. (AOA Geophysics, Inc., Houston, TX); Shedd, W. (Minerals Management Service); Frye, M. (Minerals Management Service); Ruppel, C. (USGS); Boswell, R.; Jones, E. (Chevron Energy Technology Corp., Houston, TX); Collett, T.S. (USGS); Rose, K.; Dugan, B. (Rice Univ., Houston, TX); Wood, W. (U.S. Naval Research Laboratory); Latham, T. (Chevron Energy Technology Corp., Houston, TX)

2008-07-01T23:59:59.000Z

108

Occurrence of gas hydrate in Oligocene Frio sand: Alaminos Canyon Block 818: Northern Gulf of Mexico  

SciTech Connect (OSTI)

A unique set of high-quality downhole shallow subsurface well log data combined with industry standard 3D seismic data from the Alaminos Canyon area has enabled the first detailed description of a concentrated gas hydrate accumulation within sand in the Gulf of Mexico. The gas hydrate occurs within very fine grained, immature volcaniclastic sands of the Oligocene Frio sand. Analysis of well data acquired from the Alaminos Canyon Block 818 No.1 ('Tigershark') well shows a total gas hydrate occurrence 13 m thick, with inferred gas hydrate saturation as high as 80% of sediment pore space. Average porosity in the reservoir is estimated from log data at approximately 42%. Permeability in the absence of gas hydrates, as revealed from the analysis of core samples retrieved from the well, ranges from 600 to 1500 millidarcies. The 3-D seismic data reveals a strong reflector consistent with significant increase in acoustic velocities that correlates with the top of the gas-hydrate-bearing sand. This reflector extends across an area of approximately 0.8 km{sup 2} and delineates the minimal probable extent of the gas hydrate accumulation. The base of the inferred gas-hydrate zone also correlates well with a very strong seismic reflector that indicates transition into units of significantly reduced acoustic velocity. Seismic inversion analyses indicate uniformly high gas-hydrate saturations throughout the region where the Frio sand exists within the gas hydrate stability zone. Numerical modeling of the potential production of natural gas from the interpreted accumulation indicates serious challenges for depressurization-based production in settings with strong potential pressure support from extensive underlying aquifers.

Boswell, R.D.; Shelander, D.; Lee, M.; Latham, T.; Collett, T.; Guerin, G.; Moridis, G.; Reagan, M.; Goldberg, D.

2009-07-15T23:59:59.000Z

109

Development of Alaskan gas hydrate resources: Annual report, October 1986--September 1987  

SciTech Connect (OSTI)

Solid ice-like mixtures of natural gas and water in the form of natural gas hydrated have been found immobilized in the rocks beneath the permafrost in Arctic basins and in muds under the deep water along the American continental margins, in the North Sea and several other locations around the world. It is estimated that the arctic areas of the United States may contain as much as 500 trillion SCF of natural gas in the form of gas hydrates (Lewin and Associates, 1983). While the US Arctic gas hydrate resources may have enormous potential and represent long term future source of natural gas, the recovery of this resource from reservoir frozen with gas hydrates has not been commercialized yet. Continuing study and research is essential to develop technologies which will enable a detailed characterization and assessment of this alternative natural gas resource, so that development of cost effective extraction technology.

Sharma, G.D.; Kamath, V.A.; Godbole, S.P.; Patil, S.L.; Paranjpe, S.G.; Mutalik, P.N.; Nadem, N.

1987-10-01T23:59:59.000Z

110

Development of an electrical resistivity cone for the detection of gas hydrates in marine sediments  

E-Print Network [OSTI]

Natural gas hydrates are formed when, under certain pressure and temperature conditions, gas molecules become encaged by hydrogenbonded oxygen atoms, forming a solid, ice-like crystalline substance. They have been found all over the world in both...

McClelland, Martha Ann

1994-01-01T23:59:59.000Z

111

Evaluation of the gas production economics of the gas hydrate cyclic thermal injection model. [Cyclic thermal injection  

SciTech Connect (OSTI)

The objective of the work performed under this directive is to assess whether gas hydrates could potentially be technically and economically recoverable. The technical potential and economics of recovering gas from a representative hydrate reservoir will be established using the cyclic thermal injection model, HYDMOD, appropriately modified for this effort, integrated with economics model for gas production on the North Slope of Alaska, and in the deep offshore Atlantic. The results from this effort are presented in this document. In Section 1, the engineering cost and financial analysis model used in performing the economic analysis of gas production from hydrates -- the Hydrates Gas Economics Model (HGEM) -- is described. Section 2 contains a users guide for HGEM. In Section 3, a preliminary economic assessment of the gas production economics of the gas hydrate cyclic thermal injection model is presented. Section 4 contains a summary critique of existing hydrate gas recovery models. Finally, Section 5 summarizes the model modification made to HYDMOD, the cyclic thermal injection model for hydrate gas recovery, in order to perform this analysis.

Kuuskraa, V.A.; Hammersheimb, E.; Sawyer, W.

1985-05-01T23:59:59.000Z

112

Hydration of gas-phase ytterbium ion complexes studied by experiment and theory  

SciTech Connect (OSTI)

Hydration of ytterbium (III) halide/hydroxide ions produced by electrospray ionization was studied in a quadrupole ion trap mass spectrometer and by density functional theory (DFT). Gas-phase YbX{sub 2}{sup +} and YbX(OH){sup +} (X = OH, Cl, Br, or I) were found to coordinate from one to four water molecules, depending on the ion residence time in the trap. From the time dependence of the hydration steps, relative reaction rates were obtained. It was determined that the second hydration was faster than both the first and third hydrations, and the fourth hydration was the slowest; this ordering reflects a combination of insufficient degrees of freedom for cooling the hot monohydrate ion and decreasing binding energies with increasing hydration number. Hydration energetics and hydrate structures were computed using two approaches of DFT. The relativistic scalar ZORA approach was used with the PBE functional and all-electron TZ2P basis sets; the B3LYP functional was used with the Stuttgart relativistic small-core ANO/ECP basis sets. The parallel experimental and computational results illuminate fundamental aspects of hydration of f-element ion complexes. The experimental observations - kinetics and extent of hydration - are discussed in relationship to the computed structures and energetics of the hydrates. The absence of pentahydrates is in accord with the DFT results, which indicate that the lowest energy structures have the fifth water molecule in the second shell.

Rutkowski, Philip X; Michelini, Maria C.; Bray, Travis H.; Russo, Nino; Marcalo, Joaquim; Gibson, John K.

2011-02-11T23:59:59.000Z

113

Evaluation of the geological relationships to gas hydrate formation and stability  

SciTech Connect (OSTI)

The summaries of regional basin analyses document that potentially economic accumulations of gas hydrates can be formed in both active and passive margin settings. The principal requirement for gas hydrate formation in either setting is abundant methane. Passive margin sediments with high sedimentation rates and sufficient sedimentary organic carbon can generate large quantities of biogenic methane for hydrate formation. Similarly, active margin locations near a terrigenous sediment source can also have high methane generation potential due to rapid burial of adequate amounts of sedimentary organic matter. Many active margins with evidence of gas hydrate presence correspond to areas subject to upwelling. Upwelling currents can enhance methane generation by increasing primary productivity and thus sedimentary organic carbon. Structural deformation of the marginal sediments at both active and passive sites can enhance gas hydrate formation by providing pathways for migration of both biogenic and thermogenic gas to the shallow gas hydrate stability zone. Additionally, conventional hydrocarbon traps may initially concentrate sufficient amounts of hydrocarbons for subsequent gas hydrate formation.

Krason, J.; Finley, P.

1988-01-01T23:59:59.000Z

114

Simulation studies of slow dynamics of hydration water in lysozyme : hydration level dependence and comparison with experiment using new time domain analysis  

E-Print Network [OSTI]

A series of Molecular Dynamics (MD) simulations using the GROMACS® package has been performed in this thesis. It is used to mimic and simulate the hydration water in Lysozyme with three different hydration levels (h = 0.3, ...

Kim, Chansoo, S.M. Massachusetts Institute of Technology

2008-01-01T23:59:59.000Z

115

Investigation of gas hydrate-bearing sandstone reservoirs at the "Mount Elbert" stratigraphic test well, Milne Point, Alaska  

SciTech Connect (OSTI)

In February 2007, the U.S. Department of Energy, BP Exploration (Alaska), Inc., and the U.S. Geological Survey conducted an extensive data collection effort at the "Mount Elbert #1" gas hydrates stratigraphic test well on the Alaska North Slope (ANS). The 22-day field program acquired significant gas hydrate-bearing reservoir data, including a full suite of open-hole well logs, over 500 feet of continuous core, and open-hole formation pressure response tests. Hole conditions, and therefore log data quality, were excellent due largely to the use of chilled oil-based drilling fluids. The logging program confirmed the existence of approximately 30 m of gashydrate saturated, fine-grained sand reservoir. Gas hydrate saturations were observed to range from 60% to 75% largely as a function of reservoir quality. Continuous wire-line coring operations (the first conducted on the ANS) achieved 85% recovery through 153 meters of section, providing more than 250 subsamples for analysis. The "Mount Elbert" data collection program culminated with open-hole tests of reservoir flow and pressure responses, as well as gas and water sample collection, using Schlumberger's Modular Formation Dynamics Tester (MDT) wireline tool. Four such tests, ranging from six to twelve hours duration, were conducted. This field program demonstrated the ability to safely and efficiently conduct a research-level openhole data acquisition program in shallow, sub-permafrost sediments. The program also demonstrated the soundness of the program's pre-drill gas hydrate characterization methods and increased confidence in gas hydrate resource assessment methodologies for the ANS.

Boswell, R.M.; Hunter, R. (ASRC Energy Services, Anchorage, AK); Collett, T. (USGS, Denver, CO); Digert, S. (BP Exploration (Alaska) Inc., Anchorage, AK); Hancock, S. (RPS Energy Canada, Calgary, Alberta, Canada); Weeks, M. (BP Exploration (Alaska) Inc., Anchorage, AK); Mt. Elbert Science Team

2008-01-01T23:59:59.000Z

116

Methane escape from gas hydrate systems in marine environment, and methane-driven oceanic eruptions  

E-Print Network [OSTI]

Methane escape from gas hydrate systems in marine environment, and methane-driven oceanic eruptions quantities of CH4 are stored in marine sediment in the form of methane hydrate, bubbles, and dissolved CH4 in pore water. Here I discuss the various pathways for methane to enter the ocean and atmosphere

Zhang, Youxue

117

Method for the photocatalytic conversion of gas hydrates  

DOE Patents [OSTI]

A method for converting methane hydrates to methanol, as well as hydrogen, through exposure to light. The process includes conversion of methane hydrates by light where a radical initiator has been added, and may be modified to include the conversion of methane hydrates with light where a photocatalyst doped by a suitable metal and an electron transfer agent to produce methanol and hydrogen. The present invention operates at temperatures below 0.degree. C., and allows for the direct conversion of methane contained within the hydrate in situ.

Taylor, Charles E. (Pittsburg, PA); Noceti, Richard P. (Pittsburg, PA); Bockrath, Bradley C. (Bethel Park, PA)

2001-01-01T23:59:59.000Z

118

Contribution of oceanic gas hydrate dissociation to the formation of Arctic Ocean methane plumes  

SciTech Connect (OSTI)

Vast quantities of methane are trapped in oceanic hydrate deposits, and there is concern that a rise in the ocean temperature will induce dissociation of these hydrate accumulations, potentially releasing large amounts of carbon into the atmosphere. Because methane is a powerful greenhouse gas, such a release could have dramatic climatic consequences. The recent discovery of active methane gas venting along the landward limit of the gas hydrate stability zone (GHSZ) on the shallow continental slope (150 m - 400 m) west of Svalbard suggests that this process may already have begun, but the source of the methane has not yet been determined. This study performs 2-D simulations of hydrate dissociation in conditions representative of the Arctic Ocean margin to assess whether such hydrates could contribute to the observed gas release. The results show that shallow, low-saturation hydrate deposits, if subjected to recently observed or future predicted temperature changes at the seafloor, can release quantities of methane at the magnitudes similar to what has been observed, and that the releases will be localized near the landward limit of the GHSZ. Both gradual and rapid warming is simulated, along with a parametric sensitivity analysis, and localized gas release is observed for most of the cases. These results resemble the recently published observations and strongly suggest that hydrate dissociation and methane release as a result of climate change may be a real phenomenon, that it could occur on decadal timescales, and that it already may be occurring.

Reagan, M.; Moridis, G.; Elliott, S.; Maltrud, M.

2011-06-01T23:59:59.000Z

119

Gas production potential of disperse low-saturation hydrate accumulations in oceanic sediments  

E-Print Network [OSTI]

bound gas in marine sediments: how much is really out there?methane hydrate in ocean sediment. Energy & Fuels 2005: 19:Accumulations in Oceanic Sediments George J. Moridis 1 and

Moridis, George J.; Sloan, E. Dendy

2006-01-01T23:59:59.000Z

120

Sulfur geochemistry of thermogenic gas hydrate and associated sediment from the Texas-Louisiana continental slope  

E-Print Network [OSTI]

total reduced sulfide (TRS), acid volatile sulfide, and citrate-dithionate and HCl extractable iron. Pore-fluid measurements included []H?S, chloride, sulfate, ammonia and total dissolved inorganic carbon. Gas hydrate hydrogen sulfide and carbon dioxide...

Gledhill, Dwight Kuehl

2001-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Basin scale assessment of gas hydrate dissociation in response to climate change  

SciTech Connect (OSTI)

Paleooceanographic evidence has been used to postulate that methane from oceanic hydrates may have had a significant role in regulating climate. However, the behavior of contemporary oceanic methane hydrate deposits subjected to rapid temperature changes, like those now occurring in the arctic and those predicted under future climate change scenarios, has only recently been investigated. Field investigations have discovered substantial methane gas plumes exiting the seafloor along the Arctic Ocean margin, and the plumes appear at depths corresponding to the upper limit of a receding gas hydrate stability zone. It has been suggested that these plumes may be the first visible signs of the dissociation of shallow hydrate deposits due to ongoing climate change in the arctic. We simulate the release of methane from oceanic deposits, including the effects of fully-coupled heat transfer, fluid flow, hydrate dissociation, and other thermodynamic processes, for systems representative of segments of the Arctic Ocean margins. The modeling encompasses a range of shallow hydrate deposits from the landward limit of the hydrate stability zone down to water depths beyond the expected range of century-scale temperature changes. We impose temperature changes corresponding to predicted rates of climate change-related ocean warming and examine the possibility of hydrate dissociation and the release of methane. The assessment is performed at local-, regional-, and basin-scales. The simulation results are consistent with the hypothesis that dissociating shallow hydrates alone can result in significant methane fluxes at the seafloor. However, the methane release is likely to be confined to a narrow region of high dissociation susceptibility, defined by depth and temperature, and that any release will be continuous and controlled, rather than explosive. This modeling also establishes the first realistic bounds for methane release along the arctic continental shelf for potential hydrate dissociation scenarios, and ongoing work may help confirm whether climate change is already impacting the stability of the vast oceanic hydrate reservoir.

Reagan, M.; Moridis, G.; Elliott, S.; Maltrud, M.; Cameron-Smith, P.

2011-07-01T23:59:59.000Z

122

Strategies for gas production from oceanic Class 3 hydrate accumulations  

E-Print Network [OSTI]

through the annular gravel pack (kg) N H = hydration numberthrough the annular gravel pack (kg/s) Q V = rate of CH 4ocean through the annular gravel pack (ST m 3 ) X i = water

Moridis, George J.; Reagan, Matthew T.

2007-01-01T23:59:59.000Z

123

Dynamical properties of the hydration shell of fully deuterated myoglobin  

SciTech Connect (OSTI)

Freeze-dried perdeuterated sperm whale myoglobin was kept in a water-saturated atmosphere in order to obtain a hydration degree of 335 {sup 1}H{sub 2}O molecules per one myoglobin molecule. Incoherent neutron scattering was performed at the neutron spectrometer TOFTOF at the FRM II in an angular range of q from 0.6 to 1.8 A{sup -1} and a temperature range from 4 to 297 K. We used neutrons with a wavelength of {lambda}{alpha}E 6 A and an energy resolution of about 65 {mu}eV corresponding to motions faster than 10 ps. At temperatures above 225 K, broad lines appear in the spectra caused by quasielastic scattering. For an explanation of these lines, we assumed that there are only two types of protons, those that are part of the hydration water (72%) and those that belong to the protein (28%). The protons of the hydration water were analyzed with the diffusion model of Singwi and Sjoelander [Phys. Rev. 119, 863 (1960)]. In this model, a water molecule stays for a time {tau}{sub 0} in a bound state performing oscillatory motions. Thereafter, the molecule performs free diffusion for the time {tau}{sub 1} in a nonbound state followed again by the oscillatory motions for {tau}{sub 0} and so forth. We used the general formulation with no simplifications as {tau}{sub 0}>>{tau}{sub 1} or {tau}{sub 1}>>{tau}{sub 0}. At room temperature, we obtained {tau}{sub 0} {alpha}E 104 ps and {tau}{sub 1} {alpha}E 37 ps. For the protein bound hydrogen, the dynamics is described by a Brownian oscillator where the protons perform overdamped motions in limited space.

Achterhold, Klaus; Parak, Fritz G. [Physik-Department E17, Technische Universitaet Muenchen, James-Franck-Strasse 1, D-85747 Garching (Germany); Ostermann, Andreas [Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II), ZWE, Lichtenbergstrasse 1, D-85747 Garching (Germany); Moulin, Martine; Haertlein, Michael [ILL-EMBL Deuteration Laboratory, Partnership for Structural Biology, 6, rue Jules Horowitz, F-38042 Grenoble Cedex 9 (France); Unruh, Tobias [Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II), ZWE, Lichtenbergstrasse 1, D-85747 Garching (Germany); Institut fuer Physik der Kondensierten Materie, Lehrstuhl fuer Kristallographie und Strukturphysik, Staudtstrasse 3, D-91058 Erlangen (Germany)

2011-10-15T23:59:59.000Z

124

GAS METHANE HYDRATES-RESEARCH STATUS, ANNOTATED BIBLIOGRAPHY, AND ENERGY IMPLICATIONS  

SciTech Connect (OSTI)

The objective of this task as originally conceived was to compile an assessment of methane hydrate deposits in Alaska from available sources and to make a very preliminary evaluation of the technical and economic feasibility of producing methane from these deposits for remote power generation. Gas hydrates have recently become a target of increased scientific investigation both from the standpoint of their resource potential to the natural gas and oil industries and of their positive and negative implications for the global environment After we performed an extensive literature review and consulted with representatives of the U.S. Geological Survey (USGS), Canadian Geological Survey, and several oil companies, it became evident that, at the current stage of gas hydrate research, the available information on methane hydrates in Alaska does not provide sufficient grounds for reaching conclusions concerning their use for energy production. Hence, the original goals of this task could not be met, and the focus was changed to the compilation and review of published documents to serve as a baseline for possible future research at the Energy & Environmental Research Center (EERC). An extensive annotated bibliography of gas hydrate publications has been completed. The EERC will reassess its future research opportunities on methane hydrates to determine where significant initial contributions could be made within the scope of limited available resources.

James Sorensen; Jaroslav Solc; Bethany Bolles

2000-07-01T23:59:59.000Z

125

Toward Production From Gas Hydrates: Current Status, Assessment of Resources, and Simulation-Based Evaluation of Technology and Potential  

E-Print Network [OSTI]

of the conventional gas reserve of 1.5x10 14 m 3 ofconventional oil and gas reserves, the assessment of theconventional fossil fuel reserves, gas hydrates are emerging

Moridis, George J.

2008-01-01T23:59:59.000Z

126

Integrating Natural Gas Hydrates in the Global Carbon Cycle  

SciTech Connect (OSTI)

We produced a two-dimensional geological time- and basin-scale model of the sedimentary margin in passive and active settings, for the simulation of the deep sedimentary methane cycle including hydrate formation. Simulation of geochemical data required development of parameterizations for bubble transport in the sediment column, and for the impact of the heterogeneity in the sediment pore fluid flow field, which represent new directions in modeling methane hydrates. The model is somewhat less sensitive to changes in ocean temperature than our previous 1-D model, due to the different methane transport mechanisms in the two codes (pore fluid flow vs. bubble migration). The model is very sensitive to reasonable changes in organic carbon deposition through geologic time, and to details of how the bubbles migrate, in particular how efficiently they are trapped as they rise through undersaturated or oxidizing chemical conditions and the hydrate stability zone. The active margin configuration reproduces the elevated hydrate saturations observed in accretionary wedges such as the Cascadia Margin, but predicts a decrease in the methane inventory per meter of coastline relative to a comparable passive margin case, and a decrease in the hydrate inventory with an increase in the plate subduction rate.

David Archer; Bruce Buffett

2011-12-31T23:59:59.000Z

127

Preliminary relative permeability estimates of methane hydrate-bearing sand  

E-Print Network [OSTI]

gas production from gas hydrate reservoirs. We estimated theof gas production from gas hydrate reservoirs. Fieldpermeability function in gas hydrate-bearing sediments is

Seol, Yongkoo; Kneafsey, Timothy J.; Tomutsa, Liviu; Moridis, George J.

2006-01-01T23:59:59.000Z

128

Predicted geoacoustic properties of gas hydrate saturated marine sediments  

E-Print Network [OSTI]

for various temperatures and pressures. . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . ? 53 3 Physical properties of grain material, pore fluid, variables affecting global fluid motion, and skeletal frame... of quartz and glass as a function of pressure 79 27 Skeletal frame elastic moduli as a function of varying hydrate concen- tration. . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . ?. 81 28...

Curtis, William Robert

2012-06-07T23:59:59.000Z

129

Alteration of gas phase ion polarizabilities upon hydration in high dielectric liquids  

E-Print Network [OSTI]

We investigate the modification of gas phase ion polarizabilities upon solvation in polar solvents and ionic liquids. To this aim, we develop a classical electrostatic theory of charged liquids composed of solvent molecules modeled as finite size dipoles, and embedding polarizable ions that consist of Drude oscillators. In qualitative agreement with ab-initio calculations of polar solvents and ionic liquids, the hydration energy of a polarizable ion in both type of dielectric liquid is shown to favor the expansion of its electronic cloud. Namely, the ion carrying no dipole moment in the gas phase acquires a dipole moment in the liquid environment, but its electron cloud also reaches an enhanced rigidity. We find that the overall effect is an increase of the gas phase polarizability upon hydration. In the specific case of ionic liquids, it is shown that this hydration process is driven by a collective solvation mechanism where the dipole moment of a polarizable ion induced by its interaction with surrounding ions self-consistently adds to the polarization of the liquid, thereby amplifying the dielectric permittivity of the medium in a substantial way. We propose this self-consistent hydration as the underlying mechanism behind the high dielectric permittivities of ionic liquids composed of small charges with negligible gas phase dipole moment. Hydration being a correlation effect, the emerging picture indicates that electrostatic correlations cannot be neglected in polarizable liquids.

Sahin Buyukdagli; Tapio Ala-Nissila

2013-04-23T23:59:59.000Z

130

Gas Hydrate Characterization in the GoM using Marine EM Methods  

SciTech Connect (OSTI)

In spite of the importance of gas hydrate as a low-carbon fuel, a possible contributor to rapid climate change, and a significant natural hazard, our current understanding about the amount and distribution of submarine gas hydrate is somewhat poor; estimates of total volume vary by at least an order of magnitude, and commercially useful concentrations of hydrate have remained an elusive target. This is largely because conventional geophysical tools have intrinsic limitations in their ability to quantitatively image hydrate. It has long been known from well logs that gas hydrate is resistive compared to the host sediments, and electrical and electromagnetic methods have been proposed and occasionally used to image hydrates. This project seeks to expand our capabilities to use electromagnetic methods to explore for gas hydrate in the marine environment. An important basic science aspect of our work was to quantify the resistivity of pure gas hydrate as a function of temperature at seafloor pressures. We designed, constructed, and tested a highpressure cell in which hydrate could be synthesized and then subjected to electrical conductivity measurements. Impedance spectroscopy at frequencies between 20 Hz and 2 MHz was used to separate the effect of the blocking electrodes from the intrinsic conductivity of the hydrate. We obtained very reproducible results that showed that pure methane hydrate was several times more resistive than the water ice that seeded the synthesis, 20,000 {Ohm}m at 0{degrees}#14;C, and that the activation energy is 30.6 kJ/mol over the temperature range of -15 to 15{degrees}#14;C. Adding silica sand to the hydrate, however, showed that the addition of the extra phase caused the conductivity of the assemblage to increase in a counterintuitive way. The fact that the increased conductivity collapsed after a percolation threshold was reached, and that the addition of glass beads does not produce a similar increase in conductivity, together suggest that while the surface of the gas hydrate grains are not intrinsically conductive, the presence of sand does increase their conductivity. In the field component of this project, we carried out an 18day cruise on the R.V. Roger Revelle in the Gulf of Mexico from 7th-Ă?Â?26th October 2008 to collect controlled-source electromagnetic (CSEM) data over four hydrate prospects; blocks AC 818, WR 313, GC 955, and MC 118. During these surveys we deployed 30 ocean bottom electromagnetic (OBEM) recorders a total of 94 times at four survey areas and towed the Scripps Undersea Electromagnetic Source Instrument (SUESI) a total of 103 hours. SUESI transmission was 200 A on a 50 m dipole antenna at heights of 70-100 m above the seafloor. We also towed a neutrally buoyant 3-axis electric field recorder behind the SUESI antenna at a constant offset of 300 m. The use of a towed receiver that is "flown" above the seafloor allowed us to operate in areas where seafloor infrastructure such as wellheads, pipelines, and installed scientific equipment existed. We reduced the data to apparent resistivity psuedosections. The most compelling results come from the hydrate observatory at MC 118, where a localized resistivity anomaly is clearly identified under the southeast crater in an otherwise uniform 1 {Ohm}m background. The data from MC 118 also show that authigenic carbonate does not necessarily express itself as a confounding resistor, as was feared at the start of this project. While the results from the other prospects are much more complicated, the data are well correlated with known geology, and line to line agreement is good. Although these data are not amenable to 1D inversion as was initially hoped, we expect to use a newly developed 2D CSEM inversion code to continue to get useful information from this rich data set.

Steven Constable

2012-03-31T23:59:59.000Z

131

Assessing the Potential of Using Hydrate Technology to Capture, Store and Transport Gas for the Caribbean Region  

E-Print Network [OSTI]

that are generally associated with chemical compounds. Gas hydrates of interest to the natural gas industry are made up of lattices containing water molecules in different ratios with methane, nitrogen, ethane, propane, iso-butane, normal butane, carbon dioxide... or carbon dioxide. 7 Transporting gas in the form of a gas hydrate can prove to be very useful in the supply chain of natural gas to meet future energy demand. Thus major challenges exist in effectively capturing, storing, transporting...

Rajnauth, Jerome Joel

2012-02-14T23:59:59.000Z

132

Derivation of a Langmuir type of model to describe the intrinsic growth rate of gas hydrates during crystallization from gas mixtures  

E-Print Network [OSTI]

Derivation of a Langmuir type of model to describe the intrinsic growth rate of gas hydrates during crystallization from gas mixtures Jean-Michel Herri* and Matthias Kwaterski Ecole Nationale Supérieure des Mines de Saint-Etienne, 158 Cours Fauriel, 42023 Saint- Etienne, France Abstract Gas Hydrates

Paris-Sud XI, Université de

133

Geological evolution and analysis of confirmed or suspected gas hydrate localities: Volume 9, Formation and stability of gas hydrates of the Middle America Trench  

SciTech Connect (OSTI)

This report presents a geological description of the Pacific margin of Mexico and Central America, including regional and local structural settings, geomorphology, geological history, stratigraphy, and physical properties. It provides the necessary regional and geological background for more in-depth research of the area. Detailed discussion of bottom simulating acoustic reflectors, sediment acoustic properties, and distribution of hydrates within the sediments are also included in this report. The formation and stabilization of gas hydrates in sediments are considered in terms of phase relations, nucleation, and crystallization constraints, gas solubility, pore fluid chemistry, inorganic diagenesis, and sediment organic content. Together with a depositional analysis of the area, this report is a better understanding of the thermal evolution of the locality. It should lead to an assessment of the potential for both biogenic and thermogenic hydrocarbon generation. 150 refs., 84 figs., 17 tabs.

Finley, P.; Krason, J.

1986-12-01T23:59:59.000Z

134

Modeling of Oceanic Gas Hydrate Instability and Methane Release in Response to Climate Change  

SciTech Connect (OSTI)

Paleooceanographic evidence has been used to postulate that methane from oceanic hydrates may have had a significant role in regulating global climate, implicating global oceanic deposits of methane gas hydrate as the main culprit in instances of rapid climate change that have occurred in the past. However, the behavior of contemporary oceanic methane hydrate deposits subjected to rapid temperature changes, like those predicted under future climate change scenarios, is poorly understood. To determine the fate of the carbon stored in these hydrates, we performed simulations of oceanic gas hydrate accumulations subjected to temperature changes at the seafloor and assessed the potential for methane release into the ocean. Our modeling analysis considered the properties of benthic sediments, the saturation and distribution of the hydrates, the ocean depth, the initial seafloor temperature, and for the first time, estimated the effect of benthic biogeochemical activity. The results show that shallow deposits--such as those found in arctic regions or in the Gulf of Mexico--can undergo rapid dissociation and produce significant methane fluxes of 2 to 13 mol/yr/m{sup 2} over a period of decades, and release up to 1,100 mol of methane per m{sup 2} of seafloor in a century. These fluxes may exceed the ability of the seafloor environment (via anaerobic oxidation of methane) to consume the released methane or sequester the carbon. These results will provide a source term to regional or global climate models in order to assess the coupling of gas hydrate deposits to changes in the global climate.

Reagan, Matthew; Reagan, Matthew T.; Moridis, George J.

2008-04-15T23:59:59.000Z

135

Gas Hydrate Equilibrium Measurements for Multi-Component Gas Mixtures and Effect of Ionic Liquid Inhibitors  

E-Print Network [OSTI]

hydrate inhibition data from a newly commissioned micro bench top reactor, a high-pressure autoclave and a rocking cell. The conditions for hydrate formation for pure methane and carbon dioxide were also measured, for validation purposes. The measured data...

Othman, Enas Azhar

2014-04-07T23:59:59.000Z

136

Dynamics of a globular protein and its hydration water studied by neutron scattering and MD simulations  

E-Print Network [OSTI]

This review article describes our neutron scattering experiments made in the past four years for the understanding of the single-particle (hydrogen atom) dynamics of a protein and its hydration water and the strong coupling ...

Chen, Sow-Hsin

2010-01-01T23:59:59.000Z

137

RESOURCE CHARACTERIZATION AND QUANTIFICATION OF NATURAL GAS-HYDRATE AND ASSOCIATED FREE-GAS ACCUMULATIONS IN THE PRUDHOE BAY - KUPARUK RIVER AREA ON THE NORTH SLOPE OF ALASKA  

SciTech Connect (OSTI)

Interim results are presented from the project designed to characterize, quantify, and determine the commercial feasibility of Alaska North Slope (ANS) gas-hydrate and associated free-gas resources in the Prudhoe Bay Unit (PBU), Kuparuk River Unit (KRU), and Milne Point Unit (MPU) areas. This collaborative research will provide practical input to reservoir and economic models, determine the technical feasibility of gas hydrate production, and influence future exploration and field extension of this potential ANS resource. The large magnitude of unconventional in-place gas (40-100 TCF) and conventional ANS gas commercialization evaluation creates industry-DOE alignment to assess this potential resource. This region uniquely combines known gas hydrate presence and existing production infrastructure. Many technical, economical, environmental, and safety issues require resolution before enabling gas hydrate commercial production. Gas hydrate energy resource potential has been studied for nearly three decades. However, this knowledge has not been applied to practical ANS gas hydrate resource development. ANS gas hydrate and associated free gas reservoirs are being studied to determine reservoir extent, stratigraphy, structure, continuity, quality, variability, and geophysical and petrophysical property distribution. Phase 1 will characterize reservoirs, lead to recoverable reserve and commercial potential estimates, and define procedures for gas hydrate drilling, data acquisition, completion, and production. Phases 2 and 3 will integrate well, core, log, and long-term production test data from additional wells, if justified by results from prior phases. The project could lead to future ANS gas hydrate pilot development. This project will help solve technical and economic issues to enable government and industry to make informed decisions regarding future commercialization of unconventional gas-hydrate resources.

Robert Hunter; Shirish Patil; Robert Casavant; Tim Collett

2003-06-02T23:59:59.000Z

138

THERMODYNAMIC MODELLING OF GAS SEMI-CLATHRATE HYDRATES USING THE ELECTROLYTE NRTL MODEL  

E-Print Network [OSTI]

THERMODYNAMIC MODELLING OF GAS SEMI-CLATHRATE HYDRATES USING THE ELECTROLYTE NRTL MODEL Matthias phase non-idealities, the electrolyte NRTL (eNRTL)-GE -model has been incorporated in our modified model of the eNRTL-interaction energy parameters has been neglected and instead, ENRTL-coefficients at 298.15 K

Paris-Sud XI, Université de

139

Feasibility of monitoring gas hydrate production with time-lapse VSP  

SciTech Connect (OSTI)

In this work we begin to examine the feasibility of using time-lapse seismic methods-specifically the vertical seismic profiling (VSP) method-for monitoring changes in hydrate accumulations that are predicted to occur during production of natural gas.

Kowalsky, M.B.; Nakagawa, S.; Moridis, G.J.

2009-11-01T23:59:59.000Z

140

New Natural Gas Storage and Transportation Capabilities Utilizing Rapid Methane Hydrate Formation Techniques  

SciTech Connect (OSTI)

Natural gas (methane as the major component) is a vital fossil fuel for the United States and around the world. One of the problems with some of this natural gas is that it is in remote areas where there is little or no local use for the gas. Nearly 50 percent worldwide natural gas reserves of ~6,254.4 trillion ft3 (tcf) is considered as stranded gas, with 36 percent or ~86 tcf of the U.S natural gas reserves totaling ~239 tcf, as stranded gas [1] [2]. The worldwide total does not include the new estimates by U.S. Geological Survey of 1,669 tcf of natural gas north of the Arctic Circle, [3] and the U.S. ~200,000 tcf of natural gas or methane hydrates, most of which are stranded gas reserves. Domestically and globally there is a need for newer and more economic storage, transportation and processing capabilities to deliver the natural gas to markets. In order to bring this resource to market, one of several expensive methods must be used: 1. Construction and operation of a natural gas pipeline 2. Construction of a storage and compression facility to compress the natural gas (CNG) at 3,000 to 3,600 psi, increasing its energy density to a point where it is more economical to ship, or 3. Construction of a cryogenic liquefaction facility to produce LNG, (requiring cryogenic temperatures at <-161 °C) and construction of a cryogenic receiving port. Each of these options for the transport requires large capital investment along with elaborate safety systems. The Department of Energy's Office of Research and Development Laboratories at the National Energy Technology Laboratory (NETL) is investigating new and novel approaches for rapid and continuous formation and production of synthetic NGHs. These synthetic hydrates can store up to 164 times their volume in gas while being maintained at 1 atmosphere and between -10 to -20°C for several weeks. Owing to these properties, new process for the economic storage and transportation of these synthetic hydrates could be envisioned for stranded gas reserves. The recent experiments and their results from the testing within NETL's 15-Liter Hydrate Cell Facility exhibit promising results. Introduction of water at the desired temperature and pressure through an NETL designed nozzle into a temperature controlled methane environment within the 15-Liter Hydrate Cell allowed for instantaneous formation of methane hydrates. The instantaneous and continuous hydrate formation process was repeated over several days while varying the flow rate of water, its' temperature, and the overall temperature of the methane environment. These results clearly indicated that hydrates formed immediately after the methane and water left the nozzle at temperatures above the freezing point of water throughout the range of operating conditions. [1] Oil and Gas Journal Vol. 160.48, Dec 22, 2008. [2] http://www.eia.doe.gov/oiaf/servicerpt/natgas/chapter3.html and http://www.eia.doe.gov/oiaf/servicerpt/natgas/pdf/tbl7.pdf [3] U.S. Geological Survey, “Circum-Arctic Resource Appraisal: Estimates of Undiscovered Oil and Gas North of the Arctic Circle,” May 2008.

Brown, T.D.; Taylor, C.E.; Bernardo, M.

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

GULF OF MEXICO SEAFLOOR STABILITY AND GAS HYDRATE MONITORING STATION PROJECT  

SciTech Connect (OSTI)

The gas hydrates research Consortium (HRC), established and administered at the University if Mississippi's Center for Marine Research and Environmental Technology (CMRET) has been active on many fronts in FY 03. Extension of the original contract through March 2004, has allowed completion of many projects that were incomplete at the end of the original project period due, primarily, to severe weather and difficulties in rescheduling test cruises. The primary objective of the Consortium, to design and emplace a remote sea floor station for the monitoring of gas hydrates in the Gulf of Mexico by the year 2005 remains intact. However, the possibility of levering HRC research off of the Joint Industries Program (JIP) became a possibility that has demanded reevaluation of some of the fundamental assumptions of the station format. These provisions are discussed in Appendix A. Landmark achievements of FY03 include: (1) Continuation of Consortium development with new researchers and additional areas of research contribution being incorporated into the project. During this period, NOAA's National Undersea Research Program's (NURP) National Institute for Undersea Science and Technology (NIUST) became a Consortium funding partner, joining DOE and Minerals Management Service (MMS); (2) Very successful annual and semiannual meetings in Oxford Mississippi in February and September, 2003; (3) Collection of piston cores from MC798 in support of the effort to evaluate the site for possible monitoring station installation; (4) Completion of the site evaluation effort including reports of all localities in the northern Gulf of Mexico where hydrates have been documented or are strongly suspected to exist on the sea floor or in the shallow subsurface; (5) Collection and preliminary evaluation of vent gases and core samples of hydrate from sites in Green Canyon and Mississippi Canyon, northern Gulf of Mexico; (6) Monitoring of gas activity on the sea floor, acoustically and thermally; (7) Design, construction, and successful deployment of an in situ pore-water sampling device; (8) Improvements to the original Raman spectrometer (methane sensor); (9) Laboratory demonstration of the impact of bacterially-produced surfactants' rates of hydrate formation; (10) Construction and sea floor emplacement and testing--with both watergun and ship noise sources--of the prototypal vertical line array (VLA); (11) Initiation of studies of spatial controls on hydrates; (12) Compilation and analyses of seismic data, including mapping of surface anomalies; (13) Additional field verification (bottom samples recovered), in support of the site selection effort; (14) Collection and preliminary analyses of gas hydrates from new sites that exhibit variant structures; (15) Initial shear wave tests carried out in shallow water; (16) Isolation of microbes for potential medicinal products development; (17) Preliminary modeling of occurrences of gas hydrates.

J. Robert Woolsey; Thomas M. McGee; Robin C. Buchannon

2004-11-01T23:59:59.000Z

142

Dynamics of Confined Water Molecules in Aqueous Salt Hydrates  

SciTech Connect (OSTI)

The unusual properties of water are largely dictated by the dynamics of the H bond network. A single water molecule has more H bonding sites than atoms, hence new experimental and theoretical investigations about this peculiar liquid have not ceased to appear. Confinement of water to nanodroplets or small molecular clusters drastically changes many of the liquid’s properties. Such confined water plays a major role in the solvation of macro molecules such as proteins and can even be essential to their properties. Despite the vast results available on bulk and confined water, discussions about the correlation between spectral and structural properties continue to this day. The fast relaxation of the OH stretching vibration in bulk water, and the variance of sample geometries in the experiments on confined water obfuscate definite interpretation of the spectroscopic results in terms of structural parameters. We present first time-resolved investigations on a new model system that is ideally suited to overcome many of the problems faced in spectroscopical investigation of the H bond network of water. Aqueous hydrates of inorganic salts provide water molecules in a crystal grid, that enables unambiguous correlations of spectroscopic and structural features. Furthermore, the confined water clusters are well isolated from each other in the crystal matrix, so different degrees of confinement can be achieved by selection of the appropriate salt.

Werhahn, Jasper C.; Pandelov, S.; Yoo, Soohaeng; Xantheas, Sotiris S.; Iglev, H.

2011-04-01T23:59:59.000Z

143

Hydration structure of salt solutions from ab initio molecular dynamics  

SciTech Connect (OSTI)

The solvation structures of Na{sup +}, K{sup +}, and Cl{sup -} ions in aqueous solution have been investigated using density functional theory (DFT) based Car-Parrinello (CP) molecular dynamics (MD) simulations. CPMD trajectories were collected for systems containing three NaCl or KCl ion pairs solvated by 122 water molecules using three different but commonly employed density functionals (BLYP, HCTH, and PBE) with electron correlation treated at the level of the generalized gradient approximation (GGA). The effect of including dispersion forces was analyzed through the use of an empirical correction to the DFT-GGA scheme. Special attention was paid to the hydration characteristics, especially the structural properties of the first solvation shell of the ions, which was investigated through ion-water radial distribution functions, coordination numbers, and angular distribution functions. There are significant differences between the present results obtained from CPMD simulations and those provided by classical MD based on either the CHARMM force field or a polarizable model. Overall, the computed structural properties are in fair agreement with the available experimental results. In particular, the observed coordination numbers 5.0-5.5, 6.0-6.4, and 6.0-6.5 for Na{sup +}, K{sup +}, and Cl{sup -}, respectively, are consistent with X-ray and neutron scattering studies but differ somewhat from some of the many other recent computational studies of these important systems. Possible reasons for the differences are discussed.

Bankura, Arindam; Carnevale, Vincenzo; Klein, Michael L. [Institute for Computational Molecular Science and Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122 (United States)

2013-01-07T23:59:59.000Z

144

Fundamentals of Natural Gas and Species Flows from Hydrate Dissociation - Applications to Safety and Sea Floor Instability  

SciTech Connect (OSTI)

Semi-analytical computational models for natural gas flow in hydrate reservoirs were developed and the effects of variations in porosity and permeability on pressure and temperature profiles and the movement of a dissociation front were studied. Experimental data for variations of gas pressure and temperature during propane hydrate formation and dissociation for crushed ice and mixture of crushed ice and glass beads under laboratory environment were obtained. A thermodynamically consistent model for multiphase liquid-gas flows trough porous media was developed. Numerical models for hydrate dissociation process in one dimensional and axisymmetric reservoir were performed. The computational model solved the general governing equations without the need for linearization. A detail module for multidimensional analysis of hydrate dissociation which make use of the FLUENT code was developed. The new model accounts for gas and liquid water flow and uses the Kim-Boshnoi model for hydrate dissociation.

Goodarz Ahmadi

2006-09-30T23:59:59.000Z

145

Fiber Optic Sensing Technology for Detecting Gas Hydrate Formation and Decomposition  

SciTech Connect (OSTI)

A fiber optic-based distributed sensing system (DSS) has been integrated with a large volume (72 L) pressure vessel providing high spatial resolution, time resolved, 3-D measurement of hybrid temperature-strain (TS) values within experimental sediment gas hydrate systems. Areas of gas hydrate formation (exothermic) and decomposition (endothermic) can be characterized through this proxy by time series analysis of discrete data points collected along the length of optical fibers placed within a sediment system. Data is visualized as a 'movie' of TS values along the length of each fiber over time. Experiments conducted in the Seafloor Processing Simulator (SPS) at Oak Ridge National Laboratory show clear indications of hydrate formation and dissociation events at expected P-T conditions given the thermodynamics of the CH4-H2O system. The high spatial resolution achieved with fiber optic technology makes the DSS a useful tool for visualizing time resolved formation and dissociation of gas hydrates in large-scale sediment experiments.

Rawn, Claudia J [ORNL; Leeman, John R [University of Oklahoma, Norman; Ulrich, Shannon M [ORNL; Alford, Jonathan E [ORNL; Phelps, Tommy Joe [ORNL; Madden, Megan Elwood [University of Oklahoma, Norman

2011-01-01T23:59:59.000Z

146

Evaluation of the geological relationships to gas hydrate formation and stability. Progress report, June 16--September 30, 1988  

SciTech Connect (OSTI)

The summaries of regional basin analyses document that potentially economic accumulations of gas hydrates can be formed in both active and passive margin settings. The principal requirement for gas hydrate formation in either setting is abundant methane. Passive margin sediments with high sedimentation rates and sufficient sedimentary organic carbon can generate large quantities of biogenic methane for hydrate formation. Similarly, active margin locations near a terrigenous sediment source can also have high methane generation potential due to rapid burial of adequate amounts of sedimentary organic matter. Many active margins with evidence of gas hydrate presence correspond to areas subject to upwelling. Upwelling currents can enhance methane generation by increasing primary productivity and thus sedimentary organic carbon. Structural deformation of the marginal sediments at both active and passive sites can enhance gas hydrate formation by providing pathways for migration of both biogenic and thermogenic gas to the shallow gas hydrate stability zone. Additionally, conventional hydrocarbon traps may initially concentrate sufficient amounts of hydrocarbons for subsequent gas hydrate formation.

Krason, J.; Finley, P.

1988-12-31T23:59:59.000Z

147

Laboratory measurements on core-scale sediment/hydrate samples to predice reservoir behavior  

E-Print Network [OSTI]

International Conference on Gas Hydrates, Trondheim, Norway,coring of near-surface gas hydrate sediments on HydrateInternational Conference on Gas Hydrates, Trondheim, Norway,

Kneafsey, Timothy J.; Seol, Yongkoo; Moridis, George J.; Tomutsa, Liviu; Freifeld, Barry M.

2008-01-01T23:59:59.000Z

148

Coalbed Methane Procduced Water Treatment Using Gas Hydrate Formation at the Wellhead  

SciTech Connect (OSTI)

Water associated with coalbed methane (CBM) production is a significant and costly process waste stream, and economic treatment and/or disposal of this water is often the key to successful and profitable CBM development. In the past decade, advances have been made in the treatment of CBM produced water. However, produced water generally must be transported in some fashion to a centralized treatment and/or disposal facility. The cost of transporting this water, whether through the development of a water distribution system or by truck, is often greater than the cost of treatment or disposal. To address this economic issue, BC Technologies (BCT), in collaboration with Oak Ridge National Laboratory (ORNL) and International Petroleum Environmental Consortium (IPEC), proposed developing a mechanical unit that could be used to treat CBM produced water by forming gas hydrates at the wellhead. This process involves creating a gas hydrate, washing it and then disassociating hydrate into water and gas molecules. The application of this technology results in three process streams: purified water, brine, and gas. The purified water can be discharged or reused for a variety of beneficial purposes and the smaller brine can be disposed of using conventional strategies. The overall objectives of this research are to develop a new treatment method for produced water where it could be purified directly at the wellhead, to determine the effectiveness of hydrate formation for the treatment of produced water with proof of concept laboratory experiments, to design a prototype-scale injector and test it in the laboratory under realistic wellhead conditions, and to demonstrate the technology under field conditions. By treating the water on-site, producers could substantially reduce their surface handling costs and economically remove impurities to a quality that would support beneficial use. Batch bench-scale experiments of the hydrate formation process and research conducted at ORNL confirmed the feasibility of the process. However, researchers at BCT were unable to develop equipment suitable for continuous operation and demonstration of the process in the field was not attempted. The significant achievements of the research area: Bench-scale batch results using carbon dioxide indicate >40% of the feed water to the hydrate formation reactor was converted to hydrate in a single pass; The batch results also indicate >23% of the feed water to the hydrate formation reactor (>50% of the hydrate formed) was converted to purified water of a quality suitable for discharge; Continuous discharge and collection of hydrates was achieved at atmospheric pressure. Continuous hydrate formation and collection at atmospheric conditions was the most significant achievement and preliminary economics indicate that if the unit could be made operable, it is potentially economic. However, the inability to continuously separate the hydrate melt fraction left the concept not ready for field demonstration and the project was terminated after Phase Two research.

BC Technologies

2009-12-30T23:59:59.000Z

149

Toward Production From Gas Hydrates: Current Status, Assessment of Resources, and Simulation-Based Evaluationof Technology and Potential  

SciTech Connect (OSTI)

Gas hydrates are a vast energy resource with global distribution in the permafrost and in the oceans. Even if conservative estimates are considered and only a small fraction is recoverable, the sheer size of the resource is so large that it demands evaluation as a potential energy source. In this review paper, we discuss the distribution of natural gas hydrate accumulations, the status of the primary international R&D programs, and the remaining science and technological challenges facing commercialization of production. After a brief examination of gas hydrate accumulations that are well characterized and appear to be models for future development and gas production, we analyze the role of numerical simulation in the assessment of the hydrate production potential, identify the data needs for reliable predictions, evaluate the status of knowledge with regard to these needs, discuss knowledge gaps and their impact, and reach the conclusion that the numerical simulation capabilities are quite advanced and that the related gaps are either not significant or are being addressed. We review the current body of literature relevant to potential productivity from different types of gas hydrate deposits, and determine that there are consistent indications of a large production potential at high rates over long periods from a wide variety of hydrate deposits. Finally, we identify (a) features, conditions, geology and techniques that are desirable in potential production targets, (b) methods to maximize production, and (c) some of the conditions and characteristics that render certain gas hydrate deposits undesirable for production.

Reagan, Matthew; Moridis, George J.; Collett, Timothy; Boswell, Ray; Kurihara, M.; Reagan, Matthew T.; Koh, Carolyn; Sloan, E. Dendy

2008-02-12T23:59:59.000Z

150

Characterizing Natural Gas Hydrates in the Deep Water Gulf of Mexico: Applications for Safe Exploration and Production Activities  

SciTech Connect (OSTI)

In 2000 Chevron began a project to learn how to characterize the natural gas hydrate deposits in the deep water portion of the Gulf of Mexico (GOM). Chevron is an active explorer and operator in the Gulf of Mexico and is aware that natural gas hydrates need to be understood to operate safely in deep water. In August 2000 Chevron worked closely with the National Energy Technology Laboratory (NETL) of the United States Department of Energy (DOE) and held a workshop in Houston, Texas to define issues concerning the characterization of natural gas hydrate deposits. Specifically, the workshop was meant to clearly show where research, the development of new technologies, and new information sources would be of benefit to the DOE and to the oil and gas industry in defining issues and solving gas hydrate problems in deep water.

Bent, Jimmy

2014-05-31T23:59:59.000Z

151

Response of oceanic hydrate-bearing sediments to thermal stresses  

E-Print Network [OSTI]

c) aqueous, gas and hydrate phase saturations, (d) waterIntrinsic Rate of Methane Gas Hydrate Decomposition”, Chem.Western Nankai Trough”, in Gas Hydrates: Challenges for the

Moridis, G.J.; Kowalsky, M.B.

2006-01-01T23:59:59.000Z

152

Examination of Hydrate Formation Methods: Trying to Create Representative Samples  

E-Print Network [OSTI]

permeability measurements of gas hydrate-bearing sediments,International Conference on Gas Hydrates, edited, p. 1058,2009), Influence of gas hydrate morphology on the seismic

Kneafsey, T.J.

2012-01-01T23:59:59.000Z

153

Modelling of Gas Clathrate Hydrate Equilibria using the Electrolyte Non-Random Two-Liquid (eNRTL) Model  

E-Print Network [OSTI]

.g. pipeline blockages by hydrates in drilling applications or gas pipelines) [6]. Species being capable of forming hydrogen bonds with the water molecules like methanol or ethylene glycol as well as water

Paris-Sud XI, Université de

154

Geological evolution and analysis of confirmed or suspected gas hydrate localities  

SciTech Connect (OSTI)

Geological factors controlling the formation, stability, and distribution of gas hydrates of the Beaufort Sea region were investigated by basin analysis. Geological, geophysical, and geochemical data from the region were assembled and evaluated to determine the relationships of geological environments and gas hydrates. The Beaufort Sea is the southern part of the Arctic Ocean offshore of the North Slope of Alaska and the Yukon and Mackenzie districts of Canada. The Beaufort Sea study region extends northward from the Arctic coasts of Alaska and Canada between Point Barrow on the west to Cape Beaufort on the east. The northern boundary of the Beaufort Sea study region is 72.5{degrees}N. The study region comprises broad continental shelves, slopes, rises, and the Arctic abyssal plain. 84 refs., 76 figs., 9 tabs.

Finley, P.D.; Krason, J.

1988-10-01T23:59:59.000Z

155

I/I ratios and halogen concentrations in pore waters of the Hydrate Ridge: Relevance for the origin of gas hydrates in ODP Leg 204  

E-Print Network [OSTI]

in fluids associated with hydrocarbons, such as oil field brines (Moran et al., 1995) or coal-bed methane association of iodine with methane allows the identification of the organic source material responsible for iodine and methane in gas hydrates. In all cores, iodine concentrations were found to increase strongly

Fehn, Udo

156

Coupling of the hydration water dynamics and the internal dynamics of actin detected by quasielastic neutron scattering  

SciTech Connect (OSTI)

Highlights: ? Quasielastic neutron scattering spectra of F-actin and G-actin were measured. ? Analysis of the samples in D{sub 2}O and H{sub 2}O provided the spectra of hydration water. ? The first layer hydration water around F-actin is less mobile than around G-actin. ? This difference in hydration water is in concert with the internal dynamics of actin. ? Water outside the first layer behaves bulk-like but influenced by the first layer. -- Abstract: In order to characterize dynamics of water molecules around F-actin and G-actin, quasielastic neutron scattering experiments were performed on powder samples of F-actin and G-actin, hydrated either with D{sub 2}O or H{sub 2}O, at hydration ratios of 0.4 and 1.0. By combined analysis of the quasielastic neutron scattering spectra, the parameter values characterizing the dynamics of the water molecules in the first hydration layer and those of the water molecules outside of the first layer were obtained. The translational diffusion coefficients (D{sub T}) of the hydration water in the first layer were found to be 1.2 × 10{sup ?5} cm{sup 2}/s and 1.7 × 10{sup ?5} cm{sup 2}/s for F-actin and G-actin, respectively, while that for bulk water was 2.8 × 10{sup ?5} cm{sup 2}/s. The residence times were 6.6 ps and 5.0 ps for F-actin and G-actin, respectively, while that for bulk water was 0.62 ps. These differences between F-actin and G-actin, indicating that the hydration water around G-actin is more mobile than that around F-actin, are in concert with the results of the internal dynamics of F-actin and G-actin, showing that G-actin fluctuates more rapidly than F-actin. This implies that the dynamics of the hydration water is coupled to the internal dynamics of the actin molecules. The D{sub T} values of the water molecules outside of the first hydration layer were found to be similar to that of bulk water though the residence times are strongly affected by the first hydration layer. This supports the recent observation on intracellular water that shows bulk-like behavior.

Fujiwara, Satoru, E-mail: fujiwara.satoru@jaea.go.jp [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan)] [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Plazanet, Marie [Laboratoire Interdisciplinaire de Physique, Université Joseph Fourier de Grenoble and CNRS (UMR5588), BP87, 38402 Saint Martin d'Hčres Cedex 9 (France)] [Laboratoire Interdisciplinaire de Physique, Université Joseph Fourier de Grenoble and CNRS (UMR5588), BP87, 38402 Saint Martin d'Hčres Cedex 9 (France); Oda, Toshiro [RIKEN SPring-8 Center, RIKEN Harima Institute, Sayo, Hyogo 679-5148 (Japan)] [RIKEN SPring-8 Center, RIKEN Harima Institute, Sayo, Hyogo 679-5148 (Japan)

2013-02-15T23:59:59.000Z

157

Methane hydrate potential and development of a shallow gas field in the arctic: The Walakpa Field North Slope Alaska  

SciTech Connect (OSTI)

The goal of the North Slope Hydrate Study is to evaluate the methane hydrate potential of the Walakpa gas field, a shallow gas field located near Barrow, Alaska. Observing, understanding, and predicting the production characteristics of the Walakpa field will be accomplished by the analysis of the reservoir geology, and of the individual well production data, derived from reservoir engineering studies conducted in the field.

Glenn, R.K.

1992-01-01T23:59:59.000Z

158

Methane hydrate potential and development of a shallow gas field in the arctic: The Walakpa Field North Slope Alaska  

SciTech Connect (OSTI)

The goal of the North Slope Hydrate Study is to evaluate the methane hydrate potential of the Walakpa gas field, a shallow gas field located near Barrow, Alaska. Observing, understanding, and predicting the production characteristics of the Walakpa field will be accomplished by the analysis of the reservoir geology, and of the individual well production data, derived from reservoir engineering studies conducted in the field.

Glenn, R.K.

1992-06-01T23:59:59.000Z

159

Application of Crunch-Flow Routines to Constrain Present and Past Carbon Fluxes at Gas-Hydrate Bearing Sites  

SciTech Connect (OSTI)

In November 2012, Oregon State University initiated the project entitled: Application of Crunch-Flow routines to constrain present and past carbon fluxes at gas-hydrate bearing sites. Within this project we developed Crunch-Flow based modeling modules that include important biogeochemical processes that need to be considered in gas hydrate environments. Our modules were applied to quantify carbon cycling in present and past systems, using data collected during several DOE-supported drilling expeditions, which include the Cascadia margin in US, Ulleung Basin in South Korea, and several sites drilled offshore India on the Bay of Bengal and Andaman Sea. Specifically, we completed modeling efforts that: 1) Reproduce the compositional and isotopic profiles observed at the eight drilled sites in the Ulleung Basin that constrain and contrast the carbon cycling pathways at chimney (high methane flux) and non-chimney sites (low methane, advective systems); 2) Simulate the Ba record in the sediments to quantify the past dynamics of methane flux in the southern Hydrate Ridge, Cascadia margin; and 3) Provide quantitative estimates of the thickness of individual mass transport deposits (MTDs), time elapsed after the MTD event, rate of sulfate reduction in the MTD, and time required to reach a new steady state at several sites drilled in the Krishna-Godavari (K-G) Basin off India. In addition we developed a hybrid model scheme by coupling a home-made MATLAB code with CrunchFlow to address the methane transport and chloride enrichment at the Ulleung Basins chimney sites, and contributed the modeling component to a study focusing on pore-scale controls on gas hydrate distribution in sediments from the Andaman Sea. These efforts resulted in two manuscripts currently under review, and contributed the modeling component of another pare, also under review. Lessons learned from these efforts are the basis of a mini-workshop to be held at Oregon State University (Feb 2014) to instruct graduate students (OSU and UW) as well as DOE staff from the NETL lab in Albany on the use of Crunch Flow for geochemical applications.

Torres, Marta

2014-01-31T23:59:59.000Z

160

Drilling and Production Testing the Methane Hydrate Resource Potential Associated with the Barrow Gas Fields  

SciTech Connect (OSTI)

In November of 2008, the Department of Energy (DOE) and the North Slope Borough (NSB) committed funding to develop a drilling plan to test the presence of hydrates in the producing formation of at least one of the Barrow Gas Fields, and to develop a production surveillance plan to monitor the behavior of hydrates as dissociation occurs. This drilling and surveillance plan was supported by earlier studies in Phase 1 of the project, including hydrate stability zone modeling, material balance modeling, and full-field history-matched reservoir simulation, all of which support the presence of methane hydrate in association with the Barrow Gas Fields. This Phase 2 of the project, conducted over the past twelve months focused on selecting an optimal location for a hydrate test well; design of a logistics, drilling, completion and testing plan; and estimating costs for the activities. As originally proposed, the project was anticipated to benefit from industry activity in northwest Alaska, with opportunities to share equipment, personnel, services and mobilization and demobilization costs with one of the then-active exploration operators. The activity level dropped off, and this benefit evaporated, although plans for drilling of development wells in the BGF's matured, offering significant synergies and cost savings over a remote stand-alone drilling project. An optimal well location was chosen at the East Barrow No.18 well pad, and a vertical pilot/monitoring well and horizontal production test/surveillance well were engineered for drilling from this location. Both wells were designed with Distributed Temperature Survey (DTS) apparatus for monitoring of the hydrate-free gas interface. Once project scope was developed, a procurement process was implemented to engage the necessary service and equipment providers, and finalize project cost estimates. Based on cost proposals from vendors, total project estimated cost is $17.88 million dollars, inclusive of design work, permitting, barging, ice road/pad construction, drilling, completion, tie-in, long-term production testing and surveillance, data analysis and technology transfer. The PRA project team and North Slope have recommended moving forward to the execution phase of this project.

Steve McRae; Thomas Walsh; Michael Dunn; Michael Cook

2010-02-22T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Geology, reservoir engineering and methane hydrate potential of the Walakpa Gas Field, North Slope, Alaska  

SciTech Connect (OSTI)

The Walakpa Gas Field, located near the city of Barrow on Alaska's North Slope, has been proven to be methane-bearing at depths of 2000--2550 feet below sea level. The producing formation is a laterally continuous, south-dipping, Lower Cretaceous shelf sandstone. The updip extent of the reservoir has not been determined by drilling, but probably extends to at least 1900 feet below sea level. Reservoir temperatures in the updip portion of the reservoir may be low enough to allow the presence of in situ methane hydrates. Reservoir net pay however, decreases to the north. Depths to the base of permafrost in the area average 940 feet. Drilling techniques and production configuration in the Walakpa field were designed to minimize formation damage to the reservoir sandstone and to eliminate methane hydrates formed during production. Drilling development of the Walakpa field was a sequential updip and lateral stepout from a previously drilled, structurally lower confirmation well. Reservoir temperature, pressure, and gas chemistry data from the development wells confirm that they have been drilled in the free-methane portion of the reservoir. Future studies in the Walakpa field are planned to determine whether or not a component of the methane production is due to the dissociation of updip in situ hydrates.

Glenn, R.K.; Allen, W.W.

1992-12-01T23:59:59.000Z

162

CHARACTERIZING NATURAL GAS HYDRATES IN THE DEEP WATER GULF OF MEXICO: APPLICATIONS FOR SAFE EXPLORATION AND PRODUCTION ACTIVITIES  

SciTech Connect (OSTI)

In 2000, Chevron began a project to learn how to characterize the natural gas hydrate deposits in the deepwater portions of the Gulf of Mexico. A Joint Industry Participation (JIP) group was formed in 2001, and a project partially funded by the U.S. Department of Energy (DOE) began in October 2001. The primary objective of this project is to develop technology and data to assist in the characterization of naturally occurring gas hydrates in the deep water Gulf of Mexico (GOM). These naturally occurring gas hydrates can cause problems relating to drilling and production of oil and gas, as well as building and operating pipelines. Other objectives of this project are to better understand how natural gas hydrates can affect seafloor stability, to gather data that can be used to study climate change, and to determine how the results of this project can be used to assess if and how gas hydrates act as a trapping mechanism for shallow oil or gas reservoirs. During April-September 2002, the JIP concentrated on: Reviewing the tasks and subtasks on the basis of the information generated during the three workshops held in March and May 2002; Writing Requests for Proposals (RFPs) and Cost, Time and Resource (CTRs) estimates to accomplish the tasks and subtasks; Reviewing proposals sent in by prospective contractors; Selecting four contractors; Selecting six sites for detailed review; and Talking to drill ship owners and operators about potential work with the JIP.

Steve Holditch; Emrys Jones

2003-01-01T23:59:59.000Z

163

CHARACTERIZING NATURAL GAS HYDRATES IN THE DEEP WATER GULF OF MEXICO: APPLICATIONS FOR SAFE EXPLORATION AND PRODUCTION ACTIVITIES  

SciTech Connect (OSTI)

In 2000, Chevron began a project to learn how to characterize the natural gas hydrate deposits in the deepwater portions of the Gulf of Mexico. A Joint Industry Participation (JIP) group was formed in 2001, and a project partially funded by the U.S. Department of Energy (DOE) began in October 2001. The primary objective of this project is to develop technology and data to assist in the characterization of naturally occurring gas hydrates in the deep water Gulf of Mexico (GOM). These naturally occurring gas hydrates can cause problems relating to drilling and production of oil and gas, as well as building and operating pipelines. Other objectives of this project are to better understand how natural gas hydrates can affect seafloor stability, to gather data that can be used to study climate change, and to determine how the results of this project can be used to assess if and how gas hydrates act as a trapping mechanism for shallow oil or gas reservoirs. During the first six months of operation, the primary activities of the JIP were to conduct and plan Workshops, which were as follows: (1) Data Collection Workshop--March 2002 (2) Drilling, Coring and Core Analyses Workshop--May 2002 (3) Modeling, Measurement and Sensors Workshop--May 2002.

Steve Holditch; Emrys Jones

2003-01-01T23:59:59.000Z

164

Marine Protists : : Distributions, Diversity and Dynamics  

E-Print Network [OSTI]

and sulfide flux at gas hydrate deposits from the Cascadiaoxidation of methane above gas hydrates at Hydrate Ridge, NEoxidation of methane above gas hydrate at Hydrate Ridge, NE

Pasulka, Alexis Leah

2013-01-01T23:59:59.000Z

165

Dynamic control of slow water transport by aquaporin 0: Implications for hydration  

E-Print Network [OSTI]

Dynamic control of slow water transport by aquaporin 0: Implications for hydration and junction as the primary water channel in this tissue but also appears to mediate the formation of thin junctions between fiber cells. AQP0 is remarkably less water perme- able than other aquaporins, but the structural basis

Shaw, David E.

166

Contribution of oceanic gas hydrate dissociation to the formation of Arctic Ocean methane plumes  

E-Print Network [OSTI]

Potential distribution of methane hydrate in the world'sisotopic evidence for methane hydrate instability duringHendy, L.L. , and R.J. Behl, Methane hydrates in quaternary

Reagan, M.

2012-01-01T23:59:59.000Z

167

Resource Characterization and Quantification of Natural Gas-Hydrate and Associated Free-Gas Accumulations in the Prudhoe Bay - Kuparuk River Area on the North Slope of Alaska  

SciTech Connect (OSTI)

Natural gas hydrates have long been considered a nuisance by the petroleum industry. Hydrates have been hazards to drilling crews, with blowouts a common occurrence if not properly accounted for in drilling plans. In gas pipelines, hydrates have formed plugs if gas was not properly dehydrated. Removing these plugs has been an expensive and time-consuming process. Recently, however, due to the geologic evidence indicating that in situ hydrates could potentially be a vast energy resource of the future, research efforts have been undertaken to explore how natural gas from hydrates might be produced. This study investigates the relative permeability of methane and brine in hydrate-bearing Alaska North Slope core samples. In February 2007, core samples were taken from the Mt. Elbert site situated between the Prudhoe Bay and Kuparuk oil fields on the Alaska North Slope. Core plugs from those core samples have been used as a platform to form hydrates and perform unsteady-steady-state displacement relative permeability experiments. The absolute permeability of Mt. Elbert core samples determined by Omni Labs was also validated as part of this study. Data taken with experimental apparatuses at the University of Alaska Fairbanks, ConocoPhillips laboratories at the Bartlesville Technology Center, and at the Arctic Slope Regional Corporation's facilities in Anchorage, Alaska, provided the basis for this study. This study finds that many difficulties inhibit the ability to obtain relative permeability data in porous media-containing hydrates. Difficulties include handling unconsolidated cores during initial core preparation work, forming hydrates in the core in such a way that promotes flow of both brine and methane, and obtaining simultaneous two-phase flow of brine and methane necessary to quantify relative permeability using unsteady-steady-state displacement methods.

Shirish Patil; Abhijit Dandekar

2008-12-31T23:59:59.000Z

168

Gas-phase chemical dynamics  

SciTech Connect (OSTI)

Research in this program is directed towards the spectroscopy of small free radicals and reactive molecules and the state-to-state dynamics of gas phase collision, energy transfer, and photodissociation phenomena. Work on several systems is summarized here.

Weston, R.E. Jr.; Sears, T.J.; Preses, J.M. [Brookhaven National Laboratory, Upton, NY (United States)

1993-12-01T23:59:59.000Z

169

Driving force and composition for multicomponent gas hydrate nucleation from supersaturated aqueous solutions  

E-Print Network [OSTI]

formation in storage. Other interests include deep ocean carbon sequestration, use of hydrate deposits

Firoozabadi, Abbas

170

Numerical simulations of depressurization-induced gas production from gas hydrate reservoirs at the Walker Ridge 312 site, northern Gulf of Mexico  

SciTech Connect (OSTI)

In 2009, the Gulf of Mexico (GOM) Gas Hydrates Joint-Industry-Project (JIP) Leg II drilling program confirmed that gas hydrate occurs at high saturations within reservoir-quality sands in the GOM. A comprehensive logging-while-drilling dataset was collected from seven wells at three sites, including two wells at the Walker Ridge 313 site. By constraining the saturations and thicknesses of hydrate-bearing sands using logging-while-drilling data, two-dimensional (2D), cylindrical, r-z and three-dimensional (3D) reservoir models were simulated. The gas hydrate occurrences inferred from seismic analysis are used to delineate the areal extent of the 3D reservoir models. Numerical simulations of gas production from the Walker Ridge reservoirs were conducted using the depressurization method at a constant bottomhole pressure. Results of these simulations indicate that these hydrate deposits are readily produced, owing to high intrinsic reservoir-quality and their proximity to the base of hydrate stability. The elevated in situ reservoir temperatures contribute to high (5–40 MMscf/day) predicted production rates. The production rates obtained from the 2D and 3D models are in close agreement. To evaluate the effect of spatial dimensions, the 2D reservoir domains were simulated at two outer radii. The results showed increased potential for formation of secondary hydrate and appearance of lag time for production rates as reservoir size increases. Similar phenomena were observed in the 3D reservoir models. The results also suggest that interbedded gas hydrate accumulations might be preferable targets for gas production in comparison with massive deposits. Hydrate in such accumulations can be readily dissociated due to heat supply from surrounding hydrate-free zones. Special cases were considered to evaluate the effect of overburden and underburden permeability on production. The obtained data show that production can be significantly degraded in comparison with a case using impermeable boundaries. The main reason for the reduced productivity is water influx from the surrounding strata; a secondary cause is gas escape into the overburden. The results dictate that in order to reliably estimate production potential, permeability of the surroundings has to be included in a model.

Myshakin, Evgeniy M.; Gaddipati, Manohar; Rose, Kelly; Anderson, Brian J.

2012-06-01T23:59:59.000Z

171

Challenges, uncertainties and issues facing gas production from gas hydrate deposits  

E-Print Network [OSTI]

of Mexico, http://www.netl.doe.gov/technologies/oil-gas/of Mexico, http://www.netl.doe.gov/technologies/oil- gas/

Moridis, G.J.

2011-01-01T23:59:59.000Z

172

Geological evolution and analysis of confirmed or suspected gas hydrate localities: Volume 10, Basin analysis, formation and stability of gas hydrates of the Aleutian Trench and the Bering Sea  

SciTech Connect (OSTI)

Four major areas with inferred gas hydrates are the subject of this study. Two of these areas, the Navarin and the Norton Basins, are located within the Bering Sea shelf, whereas the remaining areas of the Atka Basin in the central Aleutian Trench system and the eastern Aleutian Trench represent a huge region of the Aleutian Trench-Arc system. All four areas are geologically diverse and complex. Particularly the structural features of the accretionary wedge north of the Aleutian Trench still remain the subjects of scientific debates. Prior to this study, suggested presence of the gas hydrates in the four areas was based on seismic evidence, i.e., presence of bottom simulating reflectors (BSRs). Although the disclosure of the BSRs is often difficult, particularly under the structural conditions of the Navarin and Norton basins, it can be concluded that the identified BSRs are mostly represented by relatively weak and discontinuous reflectors. Under thermal and pressure conditions favorable for gas hydrate formation, the relative scarcity of the BSRs can be attributed to insufficient gas supply to the potential gas hydrate zone. Hydrocarbon gas in sediment may have biogenic, thermogenic or mixed origin. In the four studied areas, basin analysis revealed limited biogenic hydrocarbon generation. The migration of the thermogenically derived gases is probably diminished considerably due to the widespread diagenetic processes in diatomaceous strata. The latter processes resulted in the formation of the diagenetic horizons. The identified gas hydrate-related BSRs seem to be located in the areas of increased biogenic methanogenesis and faults acting as the pathways for thermogenic hydrocarbons.

Krason, J.; Ciesnik, M.

1987-01-01T23:59:59.000Z

173

Hydrate-phobic surfaces  

E-Print Network [OSTI]

Clathrate hydrate formation and subsequent plugging of deep-sea oil and gas pipelines represent a significant bottleneck for ultra deep-sea production. Current methods for hydrate mitigation focus on injecting thermodynamic ...

Smith, Jonathan David, S.M. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

174

Methane Hydrate Dissociation by Depressurization in a Mount Elbert Sandstone Sample: Experimental Observations and Numerical Simulations  

E-Print Network [OSTI]

DOE-USGS Mount Elbert gas hydrate stratigraphic test well:International Conference on Gas Hydrates, Vancouver, BritishGeologic controls on gas hydrate occurrence in the Mount

Kneafsey, T.

2012-01-01T23:59:59.000Z

175

Thermal dissociation behavior and dissociation enthalpies of methane-carbon dioxide mixed hydrates  

E-Print Network [OSTI]

Dissociation heat of mixed-gas hydrate composed of methaneInternational Conference on Gas Hydrates (ICGH 2008), 2008,and specific heats of gas hydrates under submarine and

Kwon, T.H.

2012-01-01T23:59:59.000Z

176

Controlled-source electromagnetic modeling of the masking effect of marine gas hydrate on a deeper hydrocarbon reservoir  

E-Print Network [OSTI]

that electric field data were reliable to roughly 5000 m of TX-RX offset for the 1 Hz and 3 Hz cases, and to 6500 m offset for 10 Hz. The gas hydrate/hydrocarbon model was then run with zero-value boundary conditions. The goal was to determine what effect...

Dickins, David

2009-06-02T23:59:59.000Z

177

Challenges, uncertainties and issues facing gas production from gas hydrate deposits  

E-Print Network [OSTI]

releases during drilling, and well integrity issues duringand ? Ensuring well structural integrity with subsidence inat nearby wells, seal integrity loss and associated gas

Moridis, G.J.

2011-01-01T23:59:59.000Z

178

Challenges, uncertainties and issues facing gas production from gas hydrate deposits  

E-Print Network [OSTI]

require some form of artificial lift (typically gas lift forGH development will require artificial lift such as electriclow pressure at surface. Artificial lift will be required to

Moridis, G.J.

2011-01-01T23:59:59.000Z

179

Petrographic, Mineralogic, and Geochemical Studies of Hydrocarbon-derived Authigenic Carbonate Rock from Gas Venting, Seepage, Free Gas, and Gas Hydrate Sites in the Gulf of Mexico and offshore India  

E-Print Network [OSTI]

. ACR collected from the seafloor in the Gulf of Mexico (GOM) and ACR recovered from drilled cores in the Krishna-Godawari (KG) basin offshore India were used. All study sites are associated with hydrocarbon gas venting, seepage, free gas, or gas hydrate...

Jung, Woodong

2012-02-14T23:59:59.000Z

180

X-ray computed-tomography observations of water flow through anisotropic methane hydrate-bearing sand  

E-Print Network [OSTI]

Formation of natural gas hydrates in marine sediments 1.Conceptual model of gas hydrate growth conditioned by hostPotential effects of gas hydrate on human welfare, Proc.

Seol, Yongkoo

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Electrical Resistivity Investigation of Gas Hydrate Distribution in Mississippi Canyon Block 118, Gulf of Mexico  

SciTech Connect (OSTI)

Electrical methods offer a geophysical approach for determining the sub-bottom distribution of hydrate in deep marine environments. Methane hydrate is essentially non-conductive. Hence, sediments containing hydrate are more resistive than sediments without hydrates. To date, the controlled source electromagnetic (CSEM) method has been used in marine hydrates studies. This project evaluated an alternative electrical method, direct current resistivity (DCR), for detecting marine hydrates. DCR involves the injection of direct current between two source electrodes and the simultaneous measurement of the electric potential (voltage) between multiple receiver electrodes. The DCR method provides subsurface information comparable to that produced by the CSEM method, but with less sophisticated instrumentation. Because the receivers are simple electrodes, large numbers can be deployed to achieve higher spatial resolution. In this project a prototype seafloor DCR system was developed and used to conduct a reconnaissance survey at a site of known hydrate occurrence in Mississippi Canyon Block 118. The resulting images of sub-bottom resistivities indicate that high-concentration hydrates at the site occur only in the upper 50 m, where deep-seated faults intersect the seafloor. Overall, there was evidence for much less hydrate at the site than previously thought based on available seismic and CSEM data alone.

Dunbar, John

2012-12-31T23:59:59.000Z

182

Gas Production From a Cold, Stratigraphically Bounded Hydrate Deposit at the Mount Elbert Site, North Slope, Alaska  

SciTech Connect (OSTI)

As part of an effort to identify suitable targets for a planned long-term field test, we investigate by means of numerical simulation the gas production potential from unit D, a stratigraphically bounded (Class 3) permafrost-associated hydrate occurrence penetrated in the ount Elbert well on North Slope, Alaska. This shallow, low-pressure deposit has high porosities, high intrinsic permeabilities and high hydrate saturations. It has a low temperature because of its proximity to the overlying permafrost. The simulation results indicate that vertical ells operating at a constant bottomhole pressure would produce at very low rates for a very long period. Horizontal wells increase gas production by almost two orders of magnitude, but production remains low. Sensitivity analysis indicates that the initial deposit temperature is y the far the most important factor determining production performance (and the most effective criterion for target selection) because it controls the sensible heat available to fuel dissociation.

Moridis, G.J.; Silpngarmlert, S.; Reagan, M. T.; Collett, T.S.; Zhang, K.

2009-09-01T23:59:59.000Z

183

Geology, reservoir engineering and methane hydrate potential of the Walakpa Gas Field, North Slope, Alaska. Final report  

SciTech Connect (OSTI)

The Walakpa Gas Field, located near the city of Barrow on Alaska`s North Slope, has been proven to be methane-bearing at depths of 2000--2550 feet below sea level. The producing formation is a laterally continuous, south-dipping, Lower Cretaceous shelf sandstone. The updip extent of the reservoir has not been determined by drilling, but probably extends to at least 1900 feet below sea level. Reservoir temperatures in the updip portion of the reservoir may be low enough to allow the presence of in situ methane hydrates. Reservoir net pay however, decreases to the north. Depths to the base of permafrost in the area average 940 feet. Drilling techniques and production configuration in the Walakpa field were designed to minimize formation damage to the reservoir sandstone and to eliminate methane hydrates formed during production. Drilling development of the Walakpa field was a sequential updip and lateral stepout from a previously drilled, structurally lower confirmation well. Reservoir temperature, pressure, and gas chemistry data from the development wells confirm that they have been drilled in the free-methane portion of the reservoir. Future studies in the Walakpa field are planned to determine whether or not a component of the methane production is due to the dissociation of updip in situ hydrates.

Glenn, R.K.; Allen, W.W.

1992-12-01T23:59:59.000Z

184

Evaluation of the Gas Production Potential of Marine HydrateDeposits in the Ulleung Basin of the Korean East Sea  

SciTech Connect (OSTI)

Although significant hydrate deposits are known to exist in the Ulleung Basin of the Korean East Sea, their survey and evaluation as a possible energy resource has not yet been completed. However, it is possible to develop preliminary estimates of their production potential based on the limited data that are currently available. These include the elevation and thickness of the Hydrate-Bearing Layer (HBL), the water depth, and the water temperature at the sea floor. Based on this information, we developed estimates of the local geothermal gradient that bracket its true value. Reasonable estimates of the initial pressure distribution in the HBL can be obtained because it follows closely the hydrostatic. Other critical information needs include the hydrate saturation, and the intrinsic permeabilities of the system formations. These are treated as variables, and sensitivity analysis provides an estimate of their effect on production. Based on the geology of similar deposits, it is unlikely that Ulleung Basin accumulations belong to Class 1 (involving a HBL underlain by a mobile gas zone). If Class 4 (disperse, low saturation accumulations) deposits are involved, they are not likely to have production potential. The most likely scenarios include Class 2 (HBL underlain by a zone of mobile water) or Class 3 (involving only an HBL) accumulations. Assuming nearly impermeable confining boundaries, this numerical study indicates that large production rates (several MMSCFD) are attainable from both Class 2 and Class 3 deposits using conventional technology. The sensitivity analysis demonstrates the dependence of production on the well design, the production rate, the intrinsic permeability of the HBL, the initial pressure, temperature and hydrate saturation, as well as on the thickness of the water zone (Class 2). The study also demonstrates that the presence of confining boundaries is indispensable for the commercially viable production of gas from these deposits.

Moridis, George J.; Reagan, Matthew T.; Kim, Se-Joon; Seol,Yongkoo; Zhang, Keni

2007-11-16T23:59:59.000Z

185

High pressure dynamics of hydrated protein in bio-protective trehalose environment  

E-Print Network [OSTI]

We present a pressure dependence study of the dynamics of lysozyme protein powder immersed in deuterated $\\alpha$,$\\alpha$-trehalose environment via quasi-elastic neutron scattering (QENS). The goal is to assess the baro-protective benefits of trehalose on bio-molecules by comparing the findings with those of a trehalose-free reference study. While the mean-square displacement of the trehalose-free protein (hydrated to $d_{D_2O}\\simeq$40 w\\%) as a whole, is reduced by increasing pressure, the actual observable relaxation dynamics in the pico-(ps) to nano-seconds (ns) time range remains largely unaffected by pressure - up to the maximum investigated pressure of 2.78(2) Kbar. Our observation is independent of whether or not the protein is mixed with the deuterated sugar. This suggests that the hydrated protein's conformational states at atmospheric pressure remain unaltered by hydrostatic pressures, below 2.78 Kbar. We also found the QENS response to be totally recoverable after ambient pressure conditions are restored. Circular dichroism and neutron diffraction measurements confirm that the protein structural integrity is conserved and remains intact, after pressure is released. We observe however a clear narrowing of the quasi-elastic neutron (QENS) response as the temperature is decreased from 290 K to 230 K in both cases, which we parametrize using the Kohlrausch-Williams-Watts (KWW) stretched exponential model. Only the fraction of protons that are immobile on the accessible time window of the instrument, referred to as the elastic incoherent structure factor or (EISF) is observably sensitive to pressure, increasing only marginally but systematically with increasing pressure.

S. O. Diallo; Q. Zhang; H. O'Neill; E. Mamontov

2014-09-11T23:59:59.000Z

186

Examination of core samples from the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope: Effects of retrieval and preservation  

SciTech Connect (OSTI)

Collecting and preserving undamaged core samples containing gas hydrates from depth is difficult because of the pressure and temperature changes encountered upon retrieval. Hydrate-bearing core samples were collected at the BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well in February 2007. Coring was performed while using a custom oil-based drilling mud, and the cores were retrieved by a wireline. The samples were characterized and subsampled at the surface under ambient winter arctic conditions. Samples thought to be hydrate bearing were preserved either by immersion in liquid nitrogen (LN), or by storage under methane pressure at ambient arctic conditions, and later depressurized and immersed in LN. Eleven core samples from hydrate-bearing zones were scanned using x-ray computed tomography to examine core structure and homogeneity. Features observed include radial fractures, spalling-type fractures, and reduced density near the periphery. These features were induced during sample collection, handling, and preservation. Isotopic analysis of the methane from hydrate in an initially LN-preserved core and a pressure-preserved core indicate that secondary hydrate formation occurred throughout the pressurized core, whereas none occurred in the LN-preserved core, however no hydrate was found near the periphery of the LN-preserved core. To replicate some aspects of the preservation methods, natural and laboratory-made saturated porous media samples were frozen in a variety of ways, with radial fractures observed in some LN-frozen sands, and needle-like ice crystals forming in slowly frozen clay-rich sediments. Suggestions for hydrate-bearing core preservation are presented.

Kneafsey, T.J.; Liu, T.J. H.; Winters, W.; Boswell, R.; Hunter, R.; Collett, T.S.

2011-06-01T23:59:59.000Z

187

Gas-controlled dynamic vacuum insulation with gas gate  

DOE Patents [OSTI]

Disclosed is a dynamic vacuum insulation comprising sidewalls enclosing an evacuated chamber and gas control means for releasing hydrogen gas into a chamber to increase gas molecule conduction of heat across the chamber and retrieving hydrogen gas from the chamber. The gas control means includes a metal hydride that absorbs and retains hydrogen gas at cooler temperatures and releases hydrogen gas at hotter temperatures; a hydride heating means for selectively heating the metal hydride to temperatures high enough to release hydrogen gas from the metal hydride; and gate means positioned between the metal hydride and the chamber for selectively allowing hydrogen to flow or not to flow between said metal hydride and said chamber. 25 figs.

Benson, D.K.; Potter, T.F.

1994-06-07T23:59:59.000Z

188

Gas-controlled dynamic vacuum insulation with gas gate  

DOE Patents [OSTI]

Disclosed is a dynamic vacuum insulation comprising sidewalls enclosing an evacuated chamber and gas control means for releasing hydrogen gas into a chamber to increase gas molecule conduction of heat across the chamber and retrieving hydrogen gas from the chamber. The gas control means includes a metal hydride that absorbs and retains hydrogen gas at cooler temperatures and releases hydrogen gas at hotter temperatures; a hydride heating means for selectively heating the metal hydride to temperatures high enough to release hydrogen gas from the metal hydride; and gate means positioned between the metal hydride and the chamber for selectively allowing hydrogen to flow or not to flow between said metal hydride and said chamber.

Benson, David K. (Golden, CO); Potter, Thomas F. (Denver, CO)

1994-06-07T23:59:59.000Z

189

Gas production potential of disperse low-saturation hydrate accumulations in oceanic sediments  

E-Print Network [OSTI]

to economically Page viable gas production. The overallare not promising targets for gas production. AcknowledgmentEnergy, Office of Natural Gas and Petroleum Technology,

Moridis, George J.; Sloan, E. Dendy

2006-01-01T23:59:59.000Z

190

Presentations from the March 27th - 28th Methane Hydrates Advisory...  

Broader source: Energy.gov (indexed) [DOE]

the March 27th - 28th Methane Hydrates Advisory Committee Meeting Presentations from the March 27th - 28th Methane Hydrates Advisory Committee Meeting International Gas Hydrate...

191

Methane hydrate distribution from prolonged and repeated formation in natural and compacted sand samples: X-ray CT observations  

E-Print Network [OSTI]

K. and McDonald, T. , Gas Hydrates of the Middle Americaet al. , Indian National Gas Hydrate Program Expedition 01et al. , Drilling Gas Hydrates on Hydrate Ridge, Cascadia

Rees, E.V.L.

2012-01-01T23:59:59.000Z

192

Estimation of composite thermal conductivity of a heterogeneous methane hydrate sample using iTOUGH2  

E-Print Network [OSTI]

International Conference on Gas Hydrates, Trondheim, Norway,Challenges for the future/gas hydrates, NYAS 912, 304, 2000.C. , Thermal state of the gas hydrate reservoir, natural gas

Gupta, Arvind; Kneafsey, Timothy J.; Moridis, George J.; Seol, Yongkoo; Kowalsky, Michael B.; Sloan Jr., E.D.

2006-01-01T23:59:59.000Z

193

Methane Hydrate Program  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Program Report to Congress | Page 13 Hutchinson, D., Ruppel, C., Roberts, H., Carney, R., Smith, M., 2011. Gas hydrates in the Gulf of Mexico. In Gulf of Mexico Origin, Waters, and...

194

Gas production potential of disperse low-saturation hydrate accumulations in oceanic sediments  

E-Print Network [OSTI]

M. World crude and natural gas reserves rebound in 2000. Oilto the conventional gas reserve of 0.15x10 15 m 3 methane (

Moridis, George J.; Sloan, E. Dendy

2006-01-01T23:59:59.000Z

195

TOUGH+Hydrate v1.0 User's Manual: A Code for the Simulation of System Behavior in Hydrate-Bearing Geologic Media  

E-Print Network [OSTI]

coexistence of aqueous, gas and hydrate phases in a cell (a deposit in which water, gas and hydrate are initially atequilibrium. The initial gas and hydrate saturations are S G

Moridis, George

2008-01-01T23:59:59.000Z

196

Fluid dynamics of sinking carbon dioxide hydrate particle releases for direct ocean carbon sequestration  

E-Print Network [OSTI]

One strategy to remove anthropogenic CO? from the atmosphere to mitigate climate change is by direct ocean injection. Liquid CO? can react with seawater to form solid partially reacted CO? hydrate composite particles (pure ...

Chow, Aaron C. (Aaron Chunghin), 1978-

2008-01-01T23:59:59.000Z

197

Terr. Atmos. Ocean. Sci., Vol. 17, No. 4, 829-843, December 2006 Gas Hydrate Stability Zone in Offshore Southern Taiwan  

E-Print Network [OSTI]

in Offshore Southern Taiwan Wu-Cheng Chi 1, *, Donald L. Reed 2 , and Chih-Chin Tsai 3 (Manuscript received 17 in meeting natural gas demand in the future. To study the feasibility of recovering methane from the offshore hydrates in the sediments offshore of southern Taiwan. We used a dense grid of 6-channel and 120-channel

Lin, Andrew Tien-Shun

198

Hydrate-phobic surfaces: fundamental studies in clathrate hydrate adhesion reduction  

E-Print Network [OSTI]

Clathrate hydrate formation and subsequent plugging of deep-sea oil and gas pipelines represent a significant bottleneck for deep-sea oil and gas operations. Current methods for hydrate mitigation are expensive and energy ...

Smith, J. David

199

Effectiveness of Alcohol Cosurfactants in Hydrate Antiagglomeration Minwei Sun,  

E-Print Network [OSTI]

and deepwater oil capture. One of the most effective methods to address gas hydrate problems is through-in-water emulsions, therefore enhancing the hydrate antiagglomeration effect. 1. INTRODUCTION Gas hydrates, especially in the deep sea, formation of gas hydrates may plug flowlines.1 There are significant safety

Firoozabadi, Abbas

200

Development of a Numerical Simulator for Analyzing the Geomechanical Performance of Hydrate-Bearing Sediments  

E-Print Network [OSTI]

J. Mienert. 2004. Effect of gas hydrates melting on seafloorInternational Conference on Gas Hydrates, Trondheim, Norway,A Documented Example of Gas Hydrate Saturated Sand in the

Rutqvist, J.

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

International Conference on Gas Hydrates May 19-23, 2002, Yokohama  

E-Print Network [OSTI]

% of the natural gas fields yet to be developed in the world are medium-to-small-scale and about one established liquefied natural gas technology is only considered feasible in large-scale development. About 80, but the resources are too small to justify large investments for a pipeline or a large enough LNG (liquefied natural

Gudmundsson, Jon Steinar

202

Prediction of gas-hydrate formation conditions in production and surface facilities  

E-Print Network [OSTI]

such as methane, ethane, propane, carbon dioxide and hydrogen sulfide to binary, ternary, and natural gas mixtures. I used the Statistical Analysis Software (SAS) to find the best correlations among variables such as specific gravity and pseudoreduced pressure...

Ameripour, Sharareh

2006-10-30T23:59:59.000Z

203

In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution  

SciTech Connect (OSTI)

The primary accomplishment of the JOI Cooperative Agreement with DOE/NETL in this quarter was the deployment of tools and measurement systems on ODP Leg 204 to study hydrate deposits on Hydrate Ridge, offshore Oregon from July through September, 2002. During Leg 204, we cored and logged 9 sites on the Oregon continental margin to determine the distribution and concentration of gas hydrates in an accretionary ridge and adjacent slope basin, investigate the mechanisms that transport methane and other gases into the gas hydrate stability zone (GHSZ), and obtain constraints on physical properties of hydrates in situ. A 3D seismic survey conducted in 2000 provided images of potential subsurface fluid conduits and indicated the position of the GHSZ throughout the survey region. After coring the first site, we acquired Logging-While-Drilling (LWD) data at all but one site to provide an overview of downhole physical properties. The LWD data confirmed the general position of key seismic stratigraphic horizons and yielded an initial estimate of hydrate concentration through the proxy of in situ electrical resistivity. These records proved to be of great value in planning subsequent coring. The second new hydrate proxy to be tested was infrared thermal imaging of cores on the catwalk as rapidly as possible after retrieval. The thermal images were used to identify hydrate samples and to map estimate the distribution and texture of hydrate within the cores. Geochemical analyses of interstitial waters and of headspace and void gases provide additional information on the distribution and concentration of hydrate within the stability zone, the origin and pathway of fluids into and through the GHSZ, and the rates at which the process of gas hydrate formation is occurring. Bio- and lithostratigraphic description of cores, measurement of physical properties, and in situ pressure core sampling and thermal measurements complement the data set, providing ground-truth tests of inferred physical and sedimentological properties. Among the most interesting preliminary results are: (1) the discovery that gas hydrates are distributed through a broad depth range within the GHSZ and that different physical and chemical proxies for hydrate distribution and concentration give generally consistent results; (2) evidence for the importance of sediment properties for controlling the migration of fluids in the accretionary complex; (3) geochemical indications that the gas hydrate system at Hydrate Ridge contains significant concentrations of higher order hydrocarbons and that fractionation and mixing signals will provide important constraints on gas hydrate dynamics; and (4) the discovery of very high chlorinity values that extend for at least 10 mbsf near the summit, indicating that hydrate formation here must be very rapid.

Frank Rack; Gerhard Bohrmann; Anne Trehu; Michael Storms; Derryl Schroeder; ODP Leg 204 Shipboard Scientific Party

2002-09-30T23:59:59.000Z

204

Effect of bound state of water on hydronium ion mobility in hydrated Nafion using molecular dynamics simulations  

SciTech Connect (OSTI)

We have performed a detailed analysis of the structural properties of the sulfonate groups in terms of isolated and overlapped solvation shells in the nanostructure of hydrated Nafion membrane using classical molecular dynamics simulations. Our simulations have demonstrated the correlation between the two different areas in bound water region, i.e., the first solvation shell, and the vehicular transport of hydronium ions at different water contents. We have employed a model of the Nafion membrane using the improved force field, which is newly modified and validated by comparing the density and water diffusivity with those obtained experimentally. The first solvation shells were classified into the two types, the isolated area and the overlapped area. The mean residence times of solvent molecules explicitly showed the different behaviors in each of those areas in terms of the vehicular transport of protons: the diffusivity of classical hydronium ions in the overlapped area dominates their total diffusion at lower water contents while that in the isolated area dominates for their diffusion at higher water contents. The results provided insights into the importance role of those areas in the solvation shells for the diffusivity of vehicular transport of hydronium ions in hydrated Nafion membrane.

Mabuchi, Takuya, E-mail: mabuchi@nanoint.ifs.tohoku.ac.jp [Graduate School of Engineering, Tohoku University, Sendai, Miyagi 980-8577 (Japan); Tokumasu, Takashi [Institute of Fluid Science, Tohoku University, Sendai, Miyagi 980-8577 (Japan)

2014-09-14T23:59:59.000Z

205

A Domain Decomposition Approach for Large-Scale Simulations of Flow Processes in Hydrate-Bearing Geologic Media  

E-Print Network [OSTI]

In this deposit, water, gas, and hydrate are initially atwhen exhaustion of the free gas and hydrate resources in theAdvances in the Study of Gas Hydrates, C. Taylor and J.

Zhang, Keni

2009-01-01T23:59:59.000Z

206

Application of the Split Hopkinson Resonant Bar Test for Seismic Property Characterization of Hydrate-bearing Sand Undergoing Water Saturation  

E-Print Network [OSTI]

E.V.L. 2009. Methane Gas Hydrate Morphology and its EffectGEO-SEQ Program and Gas Hydrate Program, through theInternational Conference on Gas Hydrates , Yokohama, 856–

Nakagawa, S.

2012-01-01T23:59:59.000Z

207

Modeling pure methane hydrate dissociation using a numerical simulator from a novel combination of X-ray computed tomography and macroscopic data  

E-Print Network [OSTI]

of predicted and measured methane gas production data within the heterogeneous porous methane hydrate sample.Global Distribution of Methane Hydrate in Ocean Hydrate.

Gupta, A.

2010-01-01T23:59:59.000Z

208

Evaluation of a deposit in the vicinity of the PBU L-106 Site, North Slope, Alaska, for a potential long-term test of gas production from hydrates  

SciTech Connect (OSTI)

As part of the effort to investigate the technical feasibility of gas production from hydrate deposits, a long-term field test (lasting 18-24 months) is under consideration in a project led by the U.S. Department of Energy. We evaluate a candidate deposit involving the C-Unit in the vicinity of the PBU-L106 site in North Slope, Alaska. This deposit is stratigraphically bounded by impermeable shale top and bottom boundaries (Class 3), and is characterized by high intrinsic permeabilities, high porosity, high hydrate saturation, and a hydrostatic pressure distribution. The C-unit deposit is composed of two hydrate-bearing strata separated by a 30-ft-thick shale interlayer, and its temperatrure across its boundaries ranges between 5 and 6.5 C. We investigate by means of numerical simulation involving very fine grids the production potential of these two deposits using both vertical and horizontal wells. We also explore the sensitivity of production to key parameters such as the hydrate saturation, the formation permeability, and the permeability of the bounding shale layers. Finally, we compare the production performance of the C-Unit at the PBU-L106 site to that of the D-Unit accumulation at the Mount Elbert site, a thinner, single-layer Class 3 deposit on the North Slope of Alaska that is shallower, less-pressurized and colder (2.3-2.6 C). The results indicate that production from horizontal wells may be orders of magnitude larger than that from vertical ones. Additionally, production increases with the formation permeability, and with a decreasing permeability of the boundaries. The effect of the hydrate saturation on production is complex and depends on the time frame of production. Because of higher production, the PBU-L106 deposit appears to have an advantage as a candidate for the long-term test.

Moridis, G.J.; Reagan, M.T.; Boyle, K.L.; Zhang, K.

2010-05-01T23:59:59.000Z

209

Evaluation of the Gas Production Potential of Marine Hydrate Deposits in the Ulleung Basin of the Korean East Sea  

E-Print Network [OSTI]

through the annular gravel pack (kg) N H = hydration numberthrough the annular gravel pack (kg/s) Q V = rate of CH 4the ocean through the annular gravel pack (ST m 3 ) X = mass

Moridis, George J.; Reagan, Matthew T.; Kim, Se-Joon; Seol, Yongkoo; Zhang, Keni

2007-01-01T23:59:59.000Z

210

Molecular gas and the dynamics of galaxies  

E-Print Network [OSTI]

In this review, I discuss some highlights of recent research on molecular gas in galaxies; large-scale CO maps of nearby galaxies are being made, which extend our knowledge on global properties, radial gradients, and spiral structure of the molecular ISM. Very high resolution are provided by the interferometers, that reveal high velocity gradients in galaxy nuclei, and formation of embedded structures, like bars within bars. Observation of the CO and other lines in starburst galaxies have questioned the H2-to-CO conversion factor. Surveys of dwarfs have shown how the conversion factor depends on metallicity. The molecular content is not deficient in galaxy clusters, as is the atomic gas. Galaxy interactions are very effective to enhance gas concentrations and trigger starbursts. Nuclear disks or rings are frequently observed, that concentrate the star formation activity. Since the density of starbursting galaxies is strongly increasing with redshift, the CO lines are a privileged tool to follow evolution of galaxies and observe the ISM dynamics at high redshift: due to the high excitation of the molecular gas, the stronger high-$J$ CO lines are redshifted into the observable band, which facilitates the detection.

F. Combes

1999-02-01T23:59:59.000Z

211

X-ray CT Observations of Methane Hydrate Distribution Changes over Time in a Natural Sediment Core from the BPX-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well  

E-Print Network [OSTI]

T. and Narita, H. , 2006. Methane hydrate crystal growth ina porous medium filled with methane-saturated liquid water.Kneafsey, T.J. et al. , 2007. Methane hydrate formation and

Kneafsey, T.J.

2012-01-01T23:59:59.000Z

212

RESULTS FROM THE (1) DATA COLLECTION WORKSHOP, (2) MODELING WORKSHOP AND (3) DRILLING AND CORING METHODS WORKSHOP AS PART OF THE JOINT INDUSTRY PARTICIPATION (JIP) PROJECT TO CHARACTERIZE NATURAL GAS HYDRATES IN THE DEEPWATER GULF OF MEXICO  

SciTech Connect (OSTI)

In 2000, Chevron began a project to learn how to characterize the natural gas hydrate deposits in the deepwater portions of the Gulf of Mexico. A Joint Industry Participation (JIP) group was formed in 2001, and a project partially funded by the U.S. Department of Energy (DOE) began in October 2001. The primary objective of this project is to develop technology and data to assist in the characterization of naturally occurring gas hydrates in the deepwater Gulf of Mexico. These naturally occurring gas hydrates can cause problems relating to drilling and production of oil and gas, as well as building and operating pipelines. Other objectives of this project are to better understand how natural gas hydrates can affect seafloor stability, to gather data that can be used to study climate change, and to determine how the results of this project can be used to assess if and how gas hydrates act as a trapping mechanism for shallow oil or gas reservoirs. As part of the project, three workshops were held. The first was a data collection workshop, held in Houston during March 14-15, 2002. The purpose of this workshop was to find out what data exist on gas hydrates and to begin making that data available to the JIP. The second and third workshop, on Geoscience and Reservoir Modeling, and Drilling and Coring Methods, respectively, were held simultaneously in Houston during May 9-10, 2002. The Modeling Workshop was conducted to find out what data the various engineers, scientists and geoscientists want the JIP to collect in both the field and the laboratory. The Drilling and Coring workshop was to begin making plans on how we can collect the data required by the project's principal investigators.

Stephen A. Holditch; Emrys Jones

2002-09-01T23:59:59.000Z

213

Heat Flow and Gas Hydrates on the Continental Margin of India: Building on Results from NGHP Expedition 01  

SciTech Connect (OSTI)

The Indian National Gas Hydrate Program (NGHP) Expedition 01 presented the unique opportunity to constrain regional heat flow derived from seismic observations by using drilling data in three regions on the continental margin of India. The seismic bottom simulating reflection (BSR) is a well-documented feature in hydrate bearing sediments, and can serve as a proxy for apparent heat flow if data are available to estimate acoustic velocity and density in water and sediments, thermal conductivity, and seafloor temperature. Direct observations of temperature at depth and physical properties of the sediment obtained from drilling can be used to calibrate the seismic observations, decreasing the uncertainty of the seismically-derived estimates. Anomalies in apparent heat flow can result from a variety of sources, including sedimentation, erosion, topographic refraction and fluid flow. We constructed apparent heat flow maps for portions of the Krishna-Godavari (K-G) basin, the Mahanadi basin, and the Andaman basin and modeled anomalies using 1-D conductive thermal models. Apparent heat flow values in the Krishna-Godavari (K-G) basin and Mahanadi basin are generally 0.035 to 0.055 watts per square meter (W/m{sup 2}). The borehole data show an increase in apparent heat flow as water depth increases from 900 to 1500 m. In the SW part of the seismic grid, 1D modeling of the effect of sedimentation on heat flow shows that {approx}50% of the observed increase in apparent heat flow with increasing water depth can be attributed to trapping of sediments behind a 'toe-thrust' ridge that is forming along the seaward edge of a thick, rapidly accumulating deltaic sediment pile. The remainder of the anomaly can be explained either by a decrease in thermal conductivity of the sediments filling the slope basin or by lateral advection of heat through fluid flow along stratigraphic horizons within the basin and through flexural faults in the crest of the anticline. Such flow probably plays a role in bringing methane into the ridge formed by the toe-thrust. Because of the small anomaly due to this process and the uncertainty in thermal conductivity, we did not model this process explicitly. In the NE part of the K-G basin seismic grid, a number of local heat flow lows and highs are observed, which can be attributed to topographic refraction and to local fluid flow along faults, respectively. No regional anomaly can be resolved. Because of lack of continuity between the K-G basin sites within the seismic grid and those {approx}70 km to the NE in water depths of 1200 to 1500 m, we do not speculate on the reason for higher heat flow at these depths. The Mahanadi basin results, while limited in geographic extent, are similar to those for the K-G basin. The Andaman basin exhibits much lower apparent heat flow values, ranging from 0.015 to 0.025 W/m{sup 2}. Heat flow here also appears to increase with increasing water depth. The very low heat flow here is among the lowest heat flow observed anywhere and gives rise to a very thick hydrate stability zone in the sediments. Through 1D models of sedimentation (with extremely high sedimentation rates as a proxy for tectonic thickening), we concluded that the very low heat flow can probably be attributed to the combined effects of high sedimentation rate, low thermal conductivity, tectonic thickening of sediments and the cooling effect of a subducting plate in a subduction zone forearc. Like for the K-G basin, much of the local variability can be attributed to topography. The regional increase in heat flow with water depth remains unexplained because the seismic grid available to us did not extend far enough to define the local tectonic setting of the slope basin controlling this observational pattern. The results are compared to results from other margins, both active and passive. While an increase in apparent heat flow with increasing water depth is widely observed, it is likely a result of different processes in different places. The very low heat flow due to sedimentation and tectonics in the Andaman basi

Anne Trehu; Peter Kannberg

2011-06-30T23:59:59.000Z

214

Heat Flow and Gas Hydrates on the Continental Margin of India: Building on Results from NGHP Expedition 01  

SciTech Connect (OSTI)

The Indian National Gas Hydrate Program (NGHP) Expedition 01 presented the unique opportunity to constrain regional heat flow derived from seismic observations by using drilling data in three regions on the continental margin of India. The seismic bottom simulating reflection (BSR) is a well-documented feature in hydrate bearing sediments, and can serve as a proxy for apparent heat flow if data are available to estimate acoustic velocity and density in water and sediments, thermal conductivity, and seafloor temperature. Direct observations of temperature at depth and physical properties of the sediment obtained from drilling can be used to calibrate the seismic observations, decreasing the uncertainty of the seismically-derived estimates. Anomalies in apparent heat flow can result from a variety of sources, including sedimentation, erosion, topographic refraction and fluid flow. We constructed apparent heat flow maps for portions of the Krishna-Godavari (K-G) basin, the Mahanadi basin, and the Andaman basin and modeled anomalies using 1-D conductive thermal models. Apparent heat flow values in the Krishna-Godavari (K-G) basin and Mahanadi basin are generally 0.035 to 0.055 watts per square meter (W/m2). The borehole data show an increase in apparent heat flow as water depth increases from 900 to 1500 m. In the SW part of the seismic grid, 1D modeling of the effect of sedimentation on heat flow shows that ~50% of the observed increase in apparent heat flow with increasing water depth can be attributed to trapping of sediments behind a "toe-thrust" ridge that is forming along the seaward edge of a thick, rapidly accumulating deltaic sediment pile. The remainder of the anomaly can be explained either by a decrease in thermal conductivity of the sediments filling the slope basin or by lateral advection of heat through fluid flow along stratigraphic horizons within the basin and through flexural faults in the crest of the anticline. Such flow probably plays a role in bringing methane into the ridge formed by the toe-thrust. Because of the small anomaly due to this process and the uncertainty in thermal conductivity, we did not model this process explicitly. In the NE part of the K-G basin seismic grid, a number of local heat flow lows and highs are observed, which can be attributed to topographic refraction and to local fluid flow along faults, respectively. No regional anomaly can be resolved. Because of lack of continuity between the K-G basin sites within the seismic grid and those ~70 km to the NE in water depths of 1200 to 1500 m, we do not speculate on the reason for higher heat flow at these depths. The Mahanadi basin results, while limited in geographic extent, are similar to those for the KG basin. The Andaman basin exhibits much lower apparent heat flow values, ranging from 0.015 to 0.025 W/m2. Heat flow here also appears to increase with increasing water depth. The very low heat flow here is among the lowest heat flow observed anywhere and gives rise to a very thick hydrate stability zone in the sediments. Through 1D models of sedimentation (with extremely high sedimentation rates as a proxy for tectonic thickening), we concluded that the very low heat flow can probably be attributed to the combined effects of high sedimentation rate, low thermal conductivity, tectonic thickening of sediments and the cooling effect of a subducting plate in a subduction zone forearc. Like for the K-G basin, much of the local variability can be attributed to topography. The regional increase in heat flow with water depth remains unexplained because the seismic grid available to us did not extend far enough to define the local tectonic setting of the slope basin controlling this observational pattern. The results are compared to results from other margins, both active and passive. While an increase in apparent heat flow with increasing water depth is widely observed, it is likely a result of different processes in different places. The very low heat flow due to sedimentation and tectonics in the Andaman basin is at the low end of glob

Trehu, Anne; Kannberg, Peter

2011-06-30T23:59:59.000Z

215

Micromechanics of Hydrate Dissociation in Marine Sediments by Grain-Scale Simulations  

E-Print Network [OSTI]

dissociation on the strength of hydrate-bearing sediments. Dissociation of gas-hydrates in marine sediments. Introduction Gas-hydrates are solid materials formed under a range of high pressures and low temperatures seek to evaluate the mechanical response to dissoci- ation of gas-hydrates in marine sediments

Patzek, Tadeusz W.

216

Author's personal copy New surfactant for hydrate anti-agglomeration in hydrocarbon flowlines  

E-Print Network [OSTI]

Available online 10 April 2013 Keywords: Gas hydrates Hydrate anti-agglomeration Surfactants Surface adsorption a b s t r a c t Anti-agglomeration is a promising solution for gas hydrate risks in deepsea-friendly surfactant. Ă? 2013 Elsevier Inc. All rights reserved. 1. Introduction The formation of gas hydrates

Firoozabadi, Abbas

217

CHARACTERIZATION OF MIXED CO2-TBPB HYDRATE FOR REFRIGERATION APPLICATIONS  

E-Print Network [OSTI]

in a dynamic loop and an Ostwald-de Waele model was obtained. Keywords: CO2, TBPB, mixed hydrates, solubility

Paris-Sud XI, Université de

218

Gas bubble dynamics in soft materials  

E-Print Network [OSTI]

Epstein and Plesset's seminal work on the rate of gas bubble dissolution and growth in a simple liquid is generalized to render it applicable to a gas bubble embedded in a soft elastic medium. Both the underlying diffusion equation and the expression for the gas bubble pressure were modified to allow for the non-zero shear modulus of the elastic medium. The extension of the diffusion equation results in a trivial shift (by an additive constant) in the value of the diffusion coefficient, and does not change the form of the rate equations. But the use of a Generalized Young-Laplace equation for the bubble pressure resulted in significant differences on the dynamics of bubble dissolution and growth, relative to a simple liquid medium. Depending on whether the salient parameters (solute concentration, initial bubble radius, surface tension, and shear modulus) lead to bubble growth or dissolution, the effect of allowing for a non-zero shear modulus in the Generalized Young-Laplace equation is to speed up the rate of bubble growth, or to reduce the rate of bubble dissolution, respectively. The relation to previous work on visco-elastic materials is discussed, as is the connection of this work to the problem of Decompression Sickness (specifically, "the bends"). Examples of tissues to which our expressions can be applied are provided. Also, a new phenomenon is predicted whereby, for some parameter values, a bubble can be metastable and persist for long times, or it may grow, when embedded in a homogeneous under-saturated soft elastic medium.

J. M. Solano-Altamirano; John D. Malcolm; Saul Goldman

2014-10-14T23:59:59.000Z

219

METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST  

SciTech Connect (OSTI)

Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is in the final stages of a cost-shared partnership between Maurer Technology, Noble Corporation, Anadarko Petroleum, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. Hot Ice No. 1 was planned to test the Ugnu and West Sak sequences for gas hydrates and a concomitant free gas accumulation on Anadarko's 100% working interest acreage in section 30 of Township 9N, Range 8E of the Harrison Bay quadrangle of the North Slope of Alaska. The Ugnu and West Sak intervals are favorably positioned in the hydrate-stability zone over an area extending from Anadarko's acreage westward to the vicinity of the aforementioned gas-hydrate occurrences. This suggests that a large, north-to-south trending gas-hydrate accumulation may exist in that area. The presence of gas shows in the Ugnu and West Sak reservoirs in wells situated eastward and down dip of the Hot Ice location indicate that a free-gas accumulation may be trapped by gas hydrates. The Hot Ice No. 1 well was designed to core from the surface to the base of the West Sak interval using the revolutionary and new Arctic Drilling Platform in search of gas hydrate and free gas accumulations at depths of approximately 1200 to 2500 ft MD. A secondary objective was the gas-charged sands of the uppermost Campanian interval at approximately 3000 ft. Summary results of geophysical analysis of the well are presented in this report.

Donn McGuire; Steve Runyon; Richard Sigal; Bill Liddell; Thomas Williams; George Moridis

2005-02-01T23:59:59.000Z

220

HOMOGENEOUS MODELS IN GENERAL RELATIVITY AND GAS DYNAMICS  

E-Print Network [OSTI]

HOMOGENEOUS MODELS IN GENERAL RELATIVITY AND GAS DYNAMICS O. I. BOGOYAVLENSKII AND S. P. NOVIKOV analytically) in general relativity and gas dynamics. The investigation of these models is carried out begins with a short survey of results on non-trivial models (that is, those that are not integrable

Novikov, Sergei Petrovich

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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221

Comparative Assessment of Advanced Gay Hydrate Production Methods  

SciTech Connect (OSTI)

Displacing natural gas and petroleum with carbon dioxide is a proven technology for producing conventional geologic hydrocarbon reservoirs, and producing additional yields from abandoned or partially produced petroleum reservoirs. Extending this concept to natural gas hydrate production offers the potential to enhance gas hydrate recovery with concomitant permanent geologic sequestration. Numerical simulation was used to assess a suite of carbon dioxide injection techniques for producing gas hydrates from a variety of geologic deposit types. Secondary hydrate formation was found to inhibit contact of the injected CO{sub 2} regardless of injectate phase state, thus diminishing the exchange rate due to pore clogging and hydrate zone bypass of the injected fluids. Additional work is needed to develop methods of artificially introducing high-permeability pathways in gas hydrate zones if injection of CO{sub 2} in either gas, liquid, or micro-emulsion form is to be more effective in enhancing gas hydrate production rates.

M. D. White; B. P. McGrail; S. K. Wurstner

2009-06-30T23:59:59.000Z

222

Gas Dynamics of NGC 4472 R. P. Kraft(1)  

E-Print Network [OSTI]

Gas Dynamics of NGC 4472 R. P. Kraft(1) , W. R. Forman(1) , C. Jones(1) , P. E. J. Nulsen(1) M. J present preliminary results from a 100 ks XMM-Newton observation of the hot gas in the nearby massive to be falling into the Virgo cluster. We find several structures in the gas indicative of a previous epoch

Sarazin, Craig

223

New Methane Hydrate Research: Investing in Our Energy Future...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Investing in Our Energy Future August 31, 2012 - 1:37pm Addthis Methane hydrates are 3D ice-lattice structures with natural gas locked inside. If methane hydrate is either warmed...

224

Measurement of Oil and Gas Emissions from a Marine Seep  

E-Print Network [OSTI]

the gas flux from shallow gas hydrate deposits: InteractionK.A. , Potential effects of gas hydrate on human welfare,Emerging US gas resources; 4, Hydrates contain vast store of

Leifer, Ira; Boles, J R; Luyendyk, B P

2007-01-01T23:59:59.000Z

225

Complex admixtures of clathrate hydrates in a water desalination method  

DOE Patents [OSTI]

Disclosed is a method that achieves water desalination by utilizing and optimizing clathrate hydrate phenomena. Clathrate hydrates are crystalline compounds of gas and water that desalinate water by excluding salt molecules during crystallization. Contacting a hydrate forming gaseous species with water will spontaneously form hydrates at specific temperatures and pressures through the extraction of water molecules from the bulk phase followed by crystallite nucleation. Subsequent dissociation of pure hydrates yields fresh water and, if operated correctly, allows the hydrate-forming gas to be efficiently recycled into the process stream.

Simmons, Blake A. (San Francisco, CA); Bradshaw, Robert W. (Livermore, CA); Dedrick, Daniel E. (Berkeley, CA); Anderson, David W. (Riverbank, CA)

2009-07-14T23:59:59.000Z

226

Methane Recovery from Hydrate-bearing Sediments  

SciTech Connect (OSTI)

Gas hydrates are crystalline compounds made of gas and water molecules. Methane hydrates are found in marine sediments and permafrost regions; extensive amounts of methane are trapped in the form of hydrates. Methane hydrate can be an energy resource, contribute to global warming, or cause seafloor instability. This study placed emphasis on gas recovery from hydrate bearing sediments and related phenomena. The unique behavior of hydrate-bearing sediments required the development of special research tools, including new numerical algorithms (tube- and pore-network models) and experimental devices (high pressure chambers and micromodels). Therefore, the research methodology combined experimental studies, particle-scale numerical simulations, and macro-scale analyses of coupled processes. Research conducted as part of this project started with hydrate formation in sediment pores and extended to production methods and emergent phenomena. In particular, the scope of the work addressed: (1) hydrate formation and growth in pores, the assessment of formation rate, tensile/adhesive strength and their impact on sediment-scale properties, including volume change during hydrate formation and dissociation; (2) the effect of physical properties such as gas solubility, salinity, pore size, and mixed gas conditions on hydrate formation and dissociation, and it implications such as oscillatory transient hydrate formation, dissolution within the hydrate stability field, initial hydrate lens formation, and phase boundary changes in real field situations; (3) fluid conductivity in relation to pore size distribution and spatial correlation and the emergence of phenomena such as flow focusing; (4) mixed fluid flow, with special emphasis on differences between invading gas and nucleating gas, implications on relative gas conductivity for reservoir simulations, and gas recovery efficiency; (5) identification of advantages and limitations in different gas production strategies with emphasis; (6) detailed study of CH4-CO2 exchange as a unique alternative to recover CH4 gas while sequestering CO2; (7) the relevance of fines in otherwise clean sand sediments on gas recovery and related phenomena such as fines migration and clogging, vuggy structure formation, and gas-driven fracture formation during gas production by depressurization.

J. Carlos Santamarina; Costas Tsouris

2011-04-30T23:59:59.000Z

227

Overview on Hydrate Coring, Handling and Analysis  

SciTech Connect (OSTI)

Gas hydrates are crystalline, ice-like compounds of gas and water molecules that are formed under certain thermodynamic conditions. Hydrate deposits occur naturally within ocean sediments just below the sea floor at temperatures and pressures existing below about 500 meters water depth. Gas hydrate is also stable in conjunction with the permafrost in the Arctic. Most marine gas hydrate is formed of microbially generated gas. It binds huge amounts of methane into the sediments. Worldwide, gas hydrate is estimated to hold about 1016 kg of organic carbon in the form of methane (Kvenvolden et al., 1993). Gas hydrate is one of the fossil fuel resources that is yet untapped, but may play a major role in meeting the energy challenge of this century. In June 2002, Westport Technology Center was requested by the Department of Energy (DOE) to prepare a ''Best Practices Manual on Gas Hydrate Coring, Handling and Analysis'' under Award No. DE-FC26-02NT41327. The scope of the task was specifically targeted for coring sediments with hydrates in Alaska, the Gulf of Mexico (GOM) and from the present Ocean Drilling Program (ODP) drillship. The specific subjects under this scope were defined in 3 stages as follows: Stage 1: Collect information on coring sediments with hydrates, core handling, core preservation, sample transportation, analysis of the core, and long term preservation. Stage 2: Provide copies of the first draft to a list of experts and stakeholders designated by DOE. Stage 3: Produce a second draft of the manual with benefit of input from external review for delivery. The manual provides an overview of existing information available in the published literature and reports on coring, analysis, preservation and transport of gas hydrates for laboratory analysis as of June 2003. The manual was delivered as draft version 3 to the DOE Project Manager for distribution in July 2003. This Final Report is provided for records purposes.

Jon Burger; Deepak Gupta; Patrick Jacobs; John Shillinglaw

2003-06-30T23:59:59.000Z

228

Gas flux and carbonate occurrence at a shallow seep of thermogenic natural gas  

E-Print Network [OSTI]

2002), the formation of gas hydrate in the subsurface (Suessmethane from near-surface gas hydrates. Chem Geol 205:291–and their relation to gas hydrate stability. Geology 26:647–

2010-01-01T23:59:59.000Z

229

Thermochemically Driven Gas-Dynamic Fracturing (TDGF)  

SciTech Connect (OSTI)

This report concerns efforts to increase oil well productivity and efficiency via a method of heating the oil-bearing rock of the well, a technique known as Thermochemical Gas-Dynamic Fracturing (TGDF). The technique uses either a chemical reaction or a combustion event to raise the temperature of the rock of the well, thereby increasing oil velocity, and oil pumping rate. Such technology has shown promise for future application to both older wellheads and also new sites. The need for such technologies in the oil extraction field, along with the merits of the TGDF technology is examined in Chapter 1. The theoretical basis underpinning applications of TGDF is explained in Chapter 2. It is shown that productivity of depleted well can be increased by one order of magnitude after heating a reservoir region of radius 15-20 m around the well by 100 degrees 1-2 times per year. Two variants of thermal stimulation are considered: uniform heating and optimal temperature distribution in the formation region around the perforation zone. It is demonstrated that the well productivity attained by using equal amounts of thermal energy is higher by a factor of 3 to 4 in the case of optimal temperature distribution as compared to uniform distribution. Following this theoretical basis, two practical approaches to applying TDGF are considered. Chapter 3 looks at the use of chemical intiators to raise the rock temperature in the well via an exothermic chemical reaction. The requirements for such a delivery device are discussed, and several novel fuel-oxidizing mixtures (FOM) are investigated in conditions simulating those at oil-extracting depths. Such FOM mixtures, particularly ones containing nitric acid and a chemical initiator, are shown to dramatically increase the temperature of the oil-bearing rock, and thus the productivity of the well. Such tests are substantiated by preliminary fieldwork in Russian oil fields. A second, more cost effective approach to TGDF is considered in Chapter 4: use of diesel-fuel to raise the rock temperature by a combustion process in the well. The requirements for such a Gas-Vapor Generator are laid out, and the development of a prototype machine is explained. This is backed up with laboratory experiments showing that the fuel-water mixture used does significantly increase the viscosity of the oil samples. The prototype Gas-Vapor Generator is shown to be able to operate at temperatures of 240 C and pressures of 200 atm. Unfortunately, geopolitical and economic factors outside of our control led to the cancellation of the project before the field testing phase of the generator could be commenced. Nevertheless, it is to be hoped that this report demonstrates both the feasibility and desirability of the Gas-Vapor Generator approach to the application of TDGF technology in both existing and new wells, and provides a foundation for further research in the future.

Michael Goodwin

2008-12-31T23:59:59.000Z

230

Alcohol Cosurfactants in Hydrate Antiagglomeration J. Dalton York and Abbas Firoozabadi*,  

E-Print Network [OSTI]

of blockage from hydrates formed from coproduced water and hydrate- forming species in natural gas. Industry of crystalline-inclusion compounds known as gas hydrates. Water, coproduced with natural gas, forms lattice as economical and environmental considerations, natural gas is projected to be the premium fuel of the 21st

Firoozabadi, Abbas

231

METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST  

SciTech Connect (OSTI)

Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is in the final stages of a cost shared partnership between Maurer Technology, Noble Corporation, Anadarko Petroleum, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. The work scope drilled and cored a well The HOT ICE No.1 on Anadarko leases beginning in FY 2003 and completed in 2004. An on-site core analysis laboratory was built and utilized for determining the physical characteristics of the hydrates and surrounding rock. The well was drilled from a new Anadarko Arctic Platform that has a minimal footprint and environmental impact. The final efforts of the project are to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists developing reservoir models. No gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in this report.

Thomas E. Williams; Keith Millheim; Buddy King

2004-07-01T23:59:59.000Z

232

METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST  

SciTech Connect (OSTI)

Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is in the final stages of a cost shared partnership between Maurer Technology, Noble Corporation, Anadarko Petroleum, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. The work scope drilled and cored a well The HOT ICE No.1 on Anadarko leases beginning in FY 2003 and completed in 2004. An on-site core analysis laboratory was built and utilized for determining the physical characteristics of the hydrates and surrounding rock. The well was drilled from a new Anadarko Arctic Platform that has a minimal footprint and environmental impact. The final efforts of the project are to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists developing reservoir models. No gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in this report.

Thomas E. Williams; Keith Millheim; Buddy King

2004-06-01T23:59:59.000Z

233

METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST  

SciTech Connect (OSTI)

Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Oil-field engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in Arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrates agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is a cost-shared partnership between Maurer Technology, Anadarko Petroleum, Noble Corporation, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to help identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. As part of the project work scope, team members drilled and cored the HOT ICE No. 1 on Anadarko leases beginning in January 2003 and completed in March 2004. Due to scheduling constraints imposed by the Arctic drilling season, operations at the site were suspended between April 21, 2003 and January 30, 2004. An on-site core analysis laboratory was designed, constructed and used for determining physical characteristics of frozen core immediately after it was retrieved from the well. The well was drilled from a new and innovative Anadarko Arctic Platform that has a greatly reduced footprint and environmental impact. Final efforts of the project were to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists for future hydrate operations. Unfortunately, no gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in the project reports.

Thomas E. Williams; Keith Millheim; Bill Liddell

2005-03-01T23:59:59.000Z

234

Methane hydrate distribution from prolonged and repeated formation in natural and compacted sand samples: X-ray CT observations  

E-Print Network [OSTI]

Deep Ocean Field Test of Methane Hydrate Formation from aW.J. , and Mason, D.H. , Methane Hydrate Formation inNatural and Laboratory--Formed Methane Gas Hydrate. American

Rees, E.V.L.

2012-01-01T23:59:59.000Z

235

Multiple stage multiple filter hydrate store  

DOE Patents [OSTI]

An improved hydrate store for a metal halogen battery system is disclosed which employs a multiple stage, multiple filter means for separating the halogen hydrate from the liquid used in forming the hydrate. The filter means is constructed in the form of three separate sections which combine to substantially cover the interior surface of the store container. Exit conduit means is provided in association with the filter means for transmitting liquid passing through the filter means to a hydrate former subsystem. The hydrate former subsystem combines the halogen gas generated during the charging of the battery system with the liquid to form the hydrate in association with the store. Relief valve means is interposed in the exit conduit means for controlling the operation of the separate sections of the filter means, such that the liquid flow through the exit conduit means from each of the separate sections is controlled in a predetermined sequence. The three separate sections of the filter means operate in three discrete stages to provide a substantially uniform liquid flow to the hydrate former subsystem during the charging of the battery system. The separation of the liquid from the hydrate causes an increase in the density of the hydrate by concentrating the hydrate along the filter means. 7 figs.

Bjorkman, H.K. Jr.

1983-05-31T23:59:59.000Z

236

Dynamics of Gas-Fluidized Granular Rods  

E-Print Network [OSTI]

We study a quasi-two-dimensional monolayer of granular rods fluidized by a spatially and temporally homogeneous upflow of air. By tracking the position and orientation of the particles, we characterize the dynamics of the system with sufficient resolution to observe ballistic motion at the shortest time scales. Particle anisotropy gives rise to dynamical anisotropy and superdiffusive dynamics parallel to the rod's long axis, causing the parallel and perpendicular mean squared displacements to become diffusive on different timescales. The distributions of free times and free paths between collisions deviate from exponential behavior, underscoring the non-thermal character of the particle motion. The dynamics show evidence of rotational-translational coupling similar to that of an anisotropic Brownian particle. We model rotational-translation coupling in the single-particle dynamics with a modified Langevin model using non-thermal noise sources. This suggests a phenomenological approach to thinking about collections of self-propelling particles in terms of enhanced memory effects.

L. J. Daniels; Y. Park; T. C. Lubensky; D. J. Durian

2008-11-17T23:59:59.000Z

237

Detection and Production of Methane Hydrate  

SciTech Connect (OSTI)

This project seeks to understand regional differences in gas hydrate systems from the perspective of as an energy resource, geohazard, and long-term climate influence. Specifically, the effort will: (1) collect data and conceptual models that targets causes of gas hydrate variance, (2) construct numerical models that explain and predict regional-scale gas hydrate differences in 2-dimensions with minimal 'free parameters', (3) simulate hydrocarbon production from various gas hydrate systems to establish promising resource characteristics, (4) perturb different gas hydrate systems to assess potential impacts of hot fluids on seafloor stability and well stability, and (5) develop geophysical approaches that enable remote quantification of gas hydrate heterogeneities so that they can be characterized with minimal costly drilling. Our integrated program takes advantage of the fact that we have a close working team comprised of experts in distinct disciplines. The expected outcomes of this project are improved exploration and production technology for production of natural gas from methane hydrates and improved safety through understanding of seafloor and well bore stability in the presence of hydrates. The scope of this project was to more fully characterize, understand, and appreciate fundamental differences in the amount and distribution of gas hydrate and how this would affect the production potential of a hydrate accumulation in the marine environment. The effort combines existing information from locations in the ocean that are dominated by low permeability sediments with small amounts of high permeability sediments, one permafrost location where extensive hydrates exist in reservoir quality rocks and other locations deemed by mutual agreement of DOE and Rice to be appropriate. The initial ocean locations were Blake Ridge, Hydrate Ridge, Peru Margin and GOM. The permafrost location was Mallik. Although the ultimate goal of the project was to understand processes that control production potential of hydrates in marine settings, Mallik was included because of the extensive data collected in a producible hydrate accumulation. To date, such a location had not been studied in the oceanic environment. The project worked closely with ongoing projects (e.g. GOM JIP and offshore India) that are actively investigating potentially economic hydrate accumulations in marine settings. The overall approach was fivefold: (1) collect key data concerning hydrocarbon fluxes which is currently missing at all locations to be included in the study, (2) use this and existing data to build numerical models that can explain gas hydrate variance at all four locations, (3) simulate how natural gas could be produced from each location with different production strategies, (4) collect new sediment property data at these locations that are required for constraining fluxes, production simulations and assessing sediment stability, and (5) develop a method for remotely quantifying heterogeneities in gas hydrate and free gas distributions. While we generally restricted our efforts to the locations where key parameters can be measured or constrained, our ultimate aim was to make our efforts universally applicable to any hydrate accumulation.

George Hirasaki; Walter Chapman; Gerald Dickens; Colin Zelt; Brandon Dugan; Kishore Mohanty; Priyank Jaiswal

2011-12-31T23:59:59.000Z

238

Desalination utilizing clathrate hydrates (LDRD final report).  

SciTech Connect (OSTI)

Advances are reported in several aspects of clathrate hydrate desalination fundamentals necessary to develop an economical means to produce municipal quantities of potable water from seawater or brackish feedstock. These aspects include the following, (1) advances in defining the most promising systems design based on new types of hydrate guest molecules, (2) selection of optimal multi-phase reactors and separation arrangements, and, (3) applicability of an inert heat exchange fluid to moderate hydrate growth, control the morphology of the solid hydrate material formed, and facilitate separation of hydrate solids from concentrated brine. The rate of R141b hydrate formation was determined and found to depend only on the degree of supercooling. The rate of R141b hydrate formation in the presence of a heat exchange fluid depended on the degree of supercooling according to the same rate equation as pure R141b with secondary dependence on salinity. Experiments demonstrated that a perfluorocarbon heat exchange fluid assisted separation of R141b hydrates from brine. Preliminary experiments using the guest species, difluoromethane, showed that hydrate formation rates were substantial at temperatures up to at least 12 C and demonstrated partial separation of water from brine. We present a detailed molecular picture of the structure and dynamics of R141b guest molecules within water cages, obtained from ab initio calculations, molecular dynamics simulations, and Raman spectroscopy. Density functional theory calculations were used to provide an energetic and molecular orbital description of R141b stability in both large and small cages in a structure II hydrate. Additionally, the hydrate of an isomer, 1,2-dichloro-1-fluoroethane, does not form at ambient conditions because of extensive overlap of electron density between guest and host. Classical molecular dynamics simulations and laboratory trials support the results for the isomer hydrate. Molecular dynamics simulations show that R141b hydrate is stable at temperatures up to 265K, while the isomer hydrate is only stable up to 150K. Despite hydrogen bonding between guest and host, R141b molecules rotated freely within the water cage. The Raman spectrum of R141b in both the pure and hydrate phases was also compared with vibrational analysis from both computational methods. In particular, the frequency of the C-Cl stretch mode (585 cm{sup -1}) undergoes a shift to higher frequency in the hydrate phase. Raman spectra also indicate that this peak undergoes splitting and intensity variation as the temperature is decreased from 4 C to -4 C.

Simmons, Blake Alexander; Bradshaw, Robert W.; Dedrick, Daniel E.; Cygan, Randall Timothy (Sandia National Laboratories, Albuquerque, NM); Greathouse, Jeffery A. (Sandia National Laboratories, Albuquerque, NM); Majzoub, Eric H. (University of Missouri, Columbia, MO)

2008-01-01T23:59:59.000Z

239

METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST  

SciTech Connect (OSTI)

Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the US have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is in the second year of a three-year endeavor being sponsored by maurer Technology, noble, and Anadarko Petroleum, in partnership with the DOE. The purpose of the project is to build on previous and ongoing R and D in the area of onshore hydrate deposition. They plan to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. They also plan to design and implement a program to safely and economically drill, core and produce gas from arctic hydrates. The current work scope is to drill and core a well on Anadarko leases in FY 2003 and 2004. They are also using an on-site core analysis laboratory to determine some of the physical characteristics of the hydrates and surrounding rock. The well is being drilled from a new Anadarko Arctic Platform that will have minimal footprint and environmental impact. They hope to correlate geology, geophysics, logs, and drilling and production data to allow reservoir models to be calibrated. Ultimately, the goal is to form an objective technical and economic evaluation of reservoir potential in Alaska.

Thomas E. Williams; Keith Millheim; Buddy King

2003-12-01T23:59:59.000Z

240

METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST  

SciTech Connect (OSTI)

Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is in the second year of a three-year endeavor being sponsored by Maurer Technology, Noble, and Anadarko Petroleum, in partnership with the DOE. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition. We plan to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. We also plan to design and implement a program to safely and economically drill, core and produce gas from arctic hydrates. The current work scope is to drill and core a well on Anadarko leases in FY 2003 and 2004. We are also using an on-site core analysis laboratory to determine some of the physical characteristics of the hydrates and surrounding rock. The well is being drilled from a new Anadarko Arctic Platform that will have minimal footprint and environmental impact. We hope to correlate geology, geophysics, logs, and drilling and production data to allow reservoir models to be calibrated. Ultimately, our goal is to form an objective technical and economic evaluation of reservoir potential in Alaska.

Thomas E. Williams; Keith Millheim; Buddy King

2004-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Enhancement of Hydrogen Storage Capacity in Hydrate Lattices  

SciTech Connect (OSTI)

First principles electronic structure calculations of the gas phase pentagonal dodecahedron (H2O)20 (D-cage) and tetrakaidecahedron (H2O)24 (T-cage), which are building blocks of structure I (sI) hydrate lattice, suggest that these can accommodate up to a maximum of 5 and 7 guest hydrogen molecules, respectively. For the pure hydrogen hydrate, Born-Oppenheimer Molecular Dynamics (BOMD) simulations of periodic (sI) hydrate lattices indicate that the guest molecules are released into the vapor phase via the hexagonal phases of the larger T-cages. An additional mechanism for the migration between neighboring D- and T-cages was found to occur through a shared pentagonal face via the breaking and reforming of a hydrogen bond. This molecular mechanism is also found for the expulsion of a CH4 molecule from the D-cage. The presence of methane in the larger T-cages was found to block this release, therefore suggesting possible scenarios for the stabilization of these mixed guest clathrate hydrates and the potential enhancement of their hydrogen storage capacity.

Yoo, Soohaeng; Xantheas, Sotiris S.

2012-02-16T23:59:59.000Z

242

Physics 343 Lecture # 8: Green Bank trip; gas dynamics  

E-Print Network [OSTI]

the existence of additional nonluminous matter (i.e., dark matter). #12; A heretical alternative? A few bold on weak lensing (apparently, mostly dark matter that is not "collisional"). #12; Inclination's third law for v = 2R/T. #12; Gas dynamics: a Keplerian example From Herrnstein et al. (1999): water

Baker, Andrew J.

243

FRW Cosmological model with Modified Chaplygin Gas and Dynamical System  

E-Print Network [OSTI]

The Friedmann-Robertson-Walker(FRW) model with dynamical Dark Energy(DE) in the form of modified Chaplygin gas(MCG) has been investigated. The evolution equations are reduced to an autonomous system on the two dimensional phase plane and it can be interpreted as the motion of the particle in an one dimensional potential.

Nairwita Mazumder; Ritabrata Biswas; Subenoy Chakraborty

2011-06-23T23:59:59.000Z

244

The dynamics of two-phase (gas  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2 and NbSe2 . TensileTevatronPortalThe art dynamics

245

3 , LNG (Liquefied Natural Gas) -165oC  

E-Print Network [OSTI]

, , . . . , . , LNG (Liquefied Natural Gas) -165oC , . (Piped Natural Gas, PNG) , , . PNG, LNG ( 2-3 ), . (Natural Gas Hydrate, NGH) / . -20oC / . Natural Gas Hydrate (NGH) Liquefied Natural Gas (LNG) Modes of Transport and Storage

Hong, Deog Ki

246

METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST  

SciTech Connect (OSTI)

Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project was a cost-shared partnership between Maurer Technology, Noble Corporation, Anadarko Petroleum, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. The work scope included drilling and coring a well (Hot Ice No. 1) on Anadarko leases beginning in FY 2003 and completed in 2004. During the first drilling season, operations were conducted at the site between January 28, 2003 to April 30, 2003. The well was spudded and drilled to a depth of 1403 ft. Due to the onset of warmer weather, work was then suspended for the season. Operations at the site were continued after the tundra was re-opened the following season. Between January 12, 2004 and March 19, 2004, the well was drilled and cored to a final depth of 2300 ft. An on-site core analysis laboratory was built and implemented for determining physical characteristics of the hydrates and surrounding rock. The well was drilled from a new Anadarko Arctic Platform that has a minimal footprint and environmental impact. Final efforts of the project are to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists developing reservoir models and to research teams for developing future gas-hydrate projects. No gas hydrates were encountered in this well; however, a wealth of information was generated and has been documented by the project team. This Topical Report documents drilling and coring operations and other daily activities.

Ali Kadaster; Bill Liddell; Tommy Thompson; Thomas Williams; Michael Niedermayr

2005-02-01T23:59:59.000Z

247

Ice method for production of hydrogen clathrate hydrates  

DOE Patents [OSTI]

The present invention includes a method for hydrogen clathrate hydrate synthesis. First, ice and hydrogen gas are supplied to a containment volume at a first temperature and a first pressure. Next, the containment volume is pressurized with hydrogen gas to a second higher pressure, where hydrogen clathrate hydrates are formed in the process.

Lokshin, Konstantin (Santa Fe, NM); Zhao, Yusheng (Los Alamos, NM)

2008-05-13T23:59:59.000Z

248

Effects of Antiagglomerants on the Interactions between Hydrate Particles  

E-Print Network [OSTI]

production Introduction The undesirable formation of gas hydrates in natural gas pipelines, and their prevention is a problem that has received considerable interest. In subsea pipelines, the presence of water of hydrates. These crystalline compounds can agglomerate and form plugs in the pipelines. The costs associated

Firoozabadi, Abbas

249

Dynamics of Sound Waves in an Interacting Bose Gas  

E-Print Network [OSTI]

We consider a non-relativistic quantum gas of $N$ bosonic atoms confined to a box of volume $\\Lambda$ in physical space. The atoms interact with each other through a pair potential whose strength is inversely proportional to the density, $\\rho=\\frac{N}{\\Lambda}$, of the gas. We study the time evolution of coherent excitations above the ground state of the gas in a regime of large volume $\\Lambda$ and small ratio $\\frac{\\Lambda}{\\rho}$. The initial state of the gas is assumed to be close to a \\textit{product state} of one-particle wave functions that are approximately constant throughout the box. The initial one-particle wave function of an excitation is assumed to have a compact support independent of $\\Lambda$. We derive an effective non-linear equation for the time evolution of the one-particle wave function of an excitation and establish an explicit error bound tracking the accuracy of the effective non-linear dynamics in terms of the ratio $\\frac{\\Lambda}{\\rho}$. We conclude with a discussion of the dispersion law of low-energy excitations, recovering Bogolyubov's well-known formula for the speed of sound in the gas, and a dynamical instability for attractive two-body potentials.

D. -A. Deckert; J. Fröhlich; P. Pickl; A. Pizzo

2014-06-06T23:59:59.000Z

250

Pore-scale mechanisms of gas flow in tight sand reservoirs  

E-Print Network [OSTI]

Potential e?ects of gas hydrate on human welfare, Proc Natlproduction from natural gas hydrates, Energy Economics 31 (Global estimates of hydrate-bound gas in marine sediments:

Silin, D.

2011-01-01T23:59:59.000Z

251

Opacity reduction using hydrated lime injection  

SciTech Connect (OSTI)

The purpose of this investigation is to study the effects of injecting dry hydrated lime into flue gas to reduce sulfur trioxide (SO{sub 3}) concentrations and consequently stack opacity at the University of Missouri, Columbia power plant. Burning of high sulfur coal (approx. 4% by weight) at the power plant resulted in opacity violations. The opacity problem was due to sulfuric acid mist (H{sub 2}SO{sub 4}) forming at the stack from high SO{sub 3} concentrations. As a result of light scattering by the mist, a visible plume leaves the stack. Therefore, reducing high concentrations of SO{sub 3} reduces the sulfuric acid mist and consequently the opacity problem. The current hydrated lime injection system has reduced the opacity to acceptable limits. To reduce SO{sub 3} concentrations, dry hydrated lime is injected into the flue gas upstream of a particulate collection device (baghouse) and downstream of the induced draft fan. The lime is periodically injected into the flue via a pneumatic piping system. The hydrated lime is transported down the flue and deposited on the filter bags in the baghouse. As the hydrated lime is deposited on the bags a filter cake is established. The reaction between the SO{sub 3} and the hydrated lime takes place on the filter bags. The hydrated lime injection system has resulted in at least 95% reduction in the SO{sub 3} concentration. Low capital equipment requirements and operating cost coupled with easy installation and maintenance makes the system very attractive to industries with similar problems. This paper documents the hydrated lime injection system and tests the effectiveness of the system on SO{sub 3} removal and subsequent opacity reduction. Measurements Of SO{sub 3} concentrations, flue gas velocities, and temperatures have been performed at the duct work and baghouse. A complete analysis of the hydrated lime injection system is provided.

Wolf, D.E.; Seaba, J.P. [Univ. of Missouri, Columbia, MO (United States)

1993-12-31T23:59:59.000Z

252

METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST  

SciTech Connect (OSTI)

Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is a cost-shared partnership between Maurer Technology, Anadarko Petroleum, Noble Corporation, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to help identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. As part of the project work scope, team members drilled and cored a well (the Hot Ice No. 1) on Anadarko leases beginning in January 2003 and completed in March 2004. Due to scheduling constraints imposed by the Arctic drilling season, operations at the site were suspended between April 21, 2003 and January 30, 2004. An on-site core analysis laboratory was constructed and used for determining physical characteristics of frozen core immediately after it was retrieved from the well. The well was drilled from a new and innovative Anadarko Arctic Platform that has a greatly reduced footprint and environmental impact. Final efforts of the project were to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists for future hydrate operations. No gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in the project reports. Documenting the results of this effort are key to extracting lessons learned and maximizing the industry's benefits for future hydrate exploitation. In addition to the Final Report, several companion Topical Reports are being published.

Thomas E. Williams; Keith Millheim; Bill Liddell

2004-11-01T23:59:59.000Z

253

METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST  

SciTech Connect (OSTI)

Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project was a cost-shared partnership between Maurer Technology, Noble Corporation, Anadarko Petroleum, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. The work scope included drilling and coring a well (Hot Ice No. 1) on Anadarko leases beginning in FY 2003 and completed in 2004. During the first drilling season, operations were conducted at the site between January 28, 2003 to April 30, 2003. The well was spudded and drilled to a depth of 1403 ft. Due to the onset of warmer weather, work was then suspended for the season. Operations at the site were continued after the tundra was re-opened the following season. Between January 12, 2004 and March 19, 2004, the well was drilled and cored to a final depth of 2300 ft. An on-site core analysis laboratory was built and utilized for determining the physical characteristics of the hydrates and surrounding rock. The well was drilled from a new Anadarko Arctic Platform that has a minimal footprint and environmental impact. The final efforts of the project are to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists planning hydrate exploration and development projects. No gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in this and other project reports. This Topical Report contains details describing logging operations.

Steve Runyon; Mike Globe; Kent Newsham; Robert Kleinberg; Doug Griffin

2005-02-01T23:59:59.000Z

254

METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST  

SciTech Connect (OSTI)

Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is a cost-shared partnership between Maurer Technology, Anadarko Petroleum, Noble Corporation, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to help identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. As part of the project work scope, team members drilled and cored a well (the Hot Ice No. 1) on Anadarko leases beginning in January 2003 and completed in March 2004. Due to scheduling constraints imposed by the Arctic drilling season, operations at the site were suspended between April 21, 2003 and January 30, 2004. An on-site core analysis laboratory was constructed and used for determining physical characteristics of frozen core immediately after it was retrieved from the well. The well was drilled from a new and innovative Anadarko Arctic Platform that has a greatly reduced footprint and environmental impact. Final efforts of the project were to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists for future hydrate operations. No gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in the project reports. Documenting the results of this effort are key to extracting lessons learned and maximizing the industry's benefits for future hydrate exploitation.

Thomas E. Williams; Keith Millheim; Bill Liddell

2005-02-01T23:59:59.000Z

255

Model equations in rarefied gas dynamics: Viscous-slip and thermal-slip coefficients  

E-Print Network [OSTI]

Model equations in rarefied gas dynamics: Viscous-slip and thermal-slip coefficients C. E. Siewert-slip and the thermal-slip coefficients in rarefied gas dynamics. More specifically, the BGK model, the S model In reviewing numerous papers devoted to model equa- tions in rarefied gas dynamics, we have found no definitive

Siewert, Charles E.

256

Effect of Brine on Hydrate Antiagglomeration J. Dalton York and Abbas Firoozabadi*,  

E-Print Network [OSTI]

production lines often favor formation of crystalline inclusion compounds known as gas hydrates. Water, 2008. ReVised Manuscript ReceiVed March 19, 2009 Natural gas production poses a risk of flow-line hydrate blockage from coproduced water and hydrate- forming species. Our previous studies have focused

Firoozabadi, Abbas

257

Geomechanical Performance of Hydrate-Bearing Sediment in Offshore Environments  

SciTech Connect (OSTI)

The objective of this multi-year, multi-institutional research project was to develop the knowledge base and quantitative predictive capability for the description of geomechanical performance of hydrate-bearing sediments (hereafter referred to as HBS) in oceanic environments. The focus was on the determination of the envelope of hydrate stability under conditions typical of those related to the construction and operation of offshore platforms. We have developed a robust numerical simulator of hydrate behavior in geologic media by coupling a reservoir model with a commercial geomechanical code. We also investigated the geomechanical behavior of oceanic HBS using pore-scale models (conceptual and mathematical) of fluid flow, stress analysis, and damage propagation. The objective of the UC Berkeley work was to develop a grain-scale model of hydrate-bearing sediments. Hydrate dissociation alters the strength of HBS. In particular, transformation of hydrate clusters into gas and liquid water weakens the skeleton and, simultaneously, reduces the effective stress by increasing the pore pressure. The large-scale objective of the study is evaluation of geomechanical stability of offshore oil and gas production infrastructure. At Lawrence Berkeley National Laboratory (LBNL), we have developed the numerical model TOUGH + Hydrate + FLAC3D to evaluate how the formation and disassociation of hydrates in seafloor sediments affects seafloor stability. Several technical papers were published using results from this model. LBNL also developed laboratory equipment and methods to produce realistic laboratory samples of sediments containing gas hydrates so that mechanical properties could be measured in the laboratory. These properties are required to run TOUGH + Hydrate + FLAC3D to evaluate seafloor stability issues. At Texas A&M University we performed a detailed literature review to determine what gas hydrate formation properties had been measured and reported in the literature. We then used TOUGH + Hydrate to simulate the observed gas production and reservoir pressure field data at Messoyakha. We simulated various scenarios that help to explain the field behavior. We have evaluated the effect of reservoir parameters on gas recovery from hydrates. Our work should be beneficial to others who are investigating how to produce gas from a hydrate capped gas reservoir. The results also can be used to better evaluate the process of producing gas from offshore hydrates. The Schlumberger PETREL model is used in industry to the description of geologic horizons and the special distribution of properties. An interface between FLAC3D and Petrel was built by Schlumberger to allow for efficient data entry into TOUGH + Hydrate + FLAC3D.

Stephen Holditch; Tad Patzek; Jonny Rutqvist; George Moridis; Richard Plumb

2008-03-31T23:59:59.000Z

258

Dynamic characteristics of gas-water interfacial plasma under water  

SciTech Connect (OSTI)

Gas-water interfacial plasmas under water were generated in a compact space in a tube with a sandglass-like structure, where two metal wires were employed as electrodes with an applied 35 kHz ac power source. The dynamic behaviors of voltage/current were investigated for the powered electrode with/without water cover to understand the effect of the gas-water interface. It is found that the discharge exhibits periodic pulsed currents after breakdown as the powered electrode is covered with water, whereas the electrical current reveals a damped oscillation with time with a frequency about 10{sup 6} Hz as the powered electrode is in a vapor bubble. By increasing water conductivity, a discharge current waveform transition from pulse to oscillation presents in the water covering case. These suggest that the gas-water interface has a significant influence on the discharge property.

Zheng, S. J.; Zhang, Y. C.; Ke, B.; Ding, F.; Tang, Z. L.; Yang, K.; Zhu, X. D. [Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

2012-06-15T23:59:59.000Z

259

Method for controlling clathrate hydrates in fluid systems  

DOE Patents [OSTI]

Discussed is a process for preventing clathrate hydrate masses from impeding the flow of fluid in a fluid system. An additive is contacted with clathrate hydrate masses in the system to prevent those clathrate hydrate masses from impeding fluid flow. The process is particularly useful in the natural gas and petroleum production, transportation and processing industry where gas hydrate formation can cause serious problems. Additives preferably contain one or more five member and/or six member cyclic chemical groupings. Additives include poly(N-vinyl-2-pyrrolidone) and hydroxyethylcellulose, either in combination or alone.

Sloan, Jr., Earle D. (Golden, CO)

1995-01-01T23:59:59.000Z

260

Gas-Phase Molecular Dynamics: High Resolution Spectroscopy and Collision Dynamics of Transient Species  

SciTech Connect (OSTI)

This research is carried out as part of the Gas-Phase Molecular Dynamics program in the Chemistry Department at Brookhaven National Laboratory. Chemical intermediates in the elementary gas-phase reactions involved in combustion chemistry are investigated by high resolution spectroscopic tools. Production, reaction, and energy transfer processes are investigated by transient, double resonance, polarization and saturation spectroscopies, with an emphasis on technique development and connection with theory, as well as specific molecular properties.

Hall, G.E.

2011-05-31T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Gas-Phase Molecular Dynamics: High Resolution Spectroscopy and Collision Dynamics of Transient Species  

SciTech Connect (OSTI)

This research is carried out as part of the Gas-Phase Molecular Dynamics program in the Chemistry Department at Brookhaven National Laboratory. Chemical intermediates in the elementary gas-phase reactions involved in combustion chemistry are investigated by high resolution spectroscopic tools. Production, reaction, and energy transfer processes are investigated by transient, double resonance, polarization and saturation spectroscopies, with an emphasis on technique development and connection with theory, as well as specific molecular properties.

Hall G. E.; Goncharov, V.

2012-05-29T23:59:59.000Z

262

Gas-Phase Molecular Dynamics: Theoretical Studies In Spectroscopy and Chemical Dynamics  

SciTech Connect (OSTI)

The main goal of this program is the development and application of computational methods for studying chemical reaction dynamics and molecular spectroscopy in the gas phase. We are interested in developing rigorous quantum dynamics algorithms for small polyatomic systems and in implementing approximate approaches for complex ones. Particular focus is on the dynamics and kinetics of chemical reactions and on the rovibrational spectra of species involved in combustion processes. This research also explores the potential energy surfaces of these systems of interest using state-of-the-art quantum chemistry methods, and extends them to understand some important properties of materials in condensed phases and interstellar medium as well as in combustion environments.

Yu H. G.; Muckerman, J.T.

2012-05-29T23:59:59.000Z

263

Method for production of hydrocarbons from hydrates  

DOE Patents [OSTI]

A method of recovering natural gas entrapped in frozen subsurface gas hydrate formations in arctic regions. A hot supersaturated solution of CaCl.sub.2 or CaBr.sub.2, or a mixture thereof, is pumped under pressure down a wellbore and into a subsurface hydrate formation so as to hydrostatically fracture the formation. The CaCl.sub.2 /CaBr.sub.2 solution dissolves the solid hydrates and thereby releases the gas entrapped therein. Additionally, the solution contains a polymeric viscosifier, which operates to maintain in suspension finely divided crystalline CaCl.sub.2 /CaBr.sub.2 that precipitates from the supersaturated solution as it is cooled during injection into the formation.

McGuire, Patrick L. (Los Alamos, NM)

1984-01-01T23:59:59.000Z

264

Dynamic Transitions in a Two Dimensional Associating Lattice Gas Model  

E-Print Network [OSTI]

Using Monte Carlo simulations we investigate some new aspects of the phase diagram and the behavior of the diffusion coefficient in an associating lattice gas (ALG) model on different regions of the phase diagram. The ALG model combines a two dimensional lattice gas where particles interact through a soft core potential and orientational degrees of freedom. The competition between soft core potential and directional attractive forces results in a high density liquid phase, a low density liquid phase, and a gas phase. Besides anomalies in the behavior of the density with the temperature at constant pressure and of the diffusion coefficient with density at constant temperature are also found. The two liquid phases are separated by a coexistence line that ends in a bicritical point. The low density liquid phase is separated from the gas phase by a coexistence line that ends in tricritical point. The bicritical and tricritical points are linked by a critical $\\lambda$-line. The high density liquid phase and the fluid phases are separated by a second $\\tau$ critical line. We then investigate how the diffusion coefficient behaves on different regions of the chemical potential-temperature phase diagram. We find that diffusivity undergoes two types of dynamic transitions: a fragile-to-strong trans ition when the critical $\\lambda$-line is crossed by decreasing the temperature at a constant chemical potential; and a strong-to-strong transition when the $\\tau$-critical line is crossed by decreasing the temperature at a constant chemical potential.

Marcia M. Szortyka; Vera Henriques; Mauricio Girardi; Marcia C. Barbosa

2009-02-10T23:59:59.000Z

265

Rarefied gas dynamics and its applications to vacuum technology F. Sharipov  

E-Print Network [OSTI]

Rarefied gas dynamics and its applications to vacuum technology F. Sharipov Universidade Federal do Paraná, Curitiba, 81531-990, Brazil Abstract Basic concepts of rarefied gas dynamics are given in a concise form. Some problems of rarefied gas flows are considered, namely, calculations of velocity slip

Sharipov, Felix

266

Understanding Sectoral Labor Market Dynamics: An Equilibrium Analysis of the Oil and Gas Field Services  

E-Print Network [OSTI]

Understanding Sectoral Labor Market Dynamics: An Equilibrium Analysis of the Oil and Gas Field examines the response of employment and wages in the US oil and gas ...eld services industry to changes the dynamic response of wages and employment in the U.S. Oil and Gas Field Services (OGFS) industry to changes

Sadoulet, Elisabeth

267

Experimental and Numerical Observations of Hydrate Reformation during Depressurization in a Core-Scale Reactor  

SciTech Connect (OSTI)

Gas hydrate has been predicted to reform around a wellbore during depressurization-based gas production from gas hydrate-bearing reservoirs. This process has an adverse effect on gas production rates and it requires time and sometimes special measures to resume gas flow to producing wells. Due to lack of applicable field data, laboratory scale experiments remain a valuable source of information to study hydrate reformation. In this work, we report laboratory experiments and complementary numerical simulations executed to investigate the hydrate reformation phenomenon. Gas production from a pressure vessel filled with hydrate-bearing sand was induced by depressurization with and without heat flux through the boundaries. Hydrate decomposition was monitored with a medical X-ray CT scanner and pressure and temperature measurements. CT images of the hydrate-bearing sample were processed to provide 3-dimensional data of heterogeneous porosity and phase saturations suitable for numerical simulations. In the experiments, gas hydrate reformation was observed only in the case of no-heat supply from surroundings, a finding consistent with numerical simulation. By allowing gas production on either side of the core, numerical simulations showed that initial hydrate distribution patterns affect gas distribution and flow inside the sample. This is a direct consequence of the heterogeneous pore network resulting in varying hydraulic properties of the hydrate-bearing sediment.

Seol, Yongkoo; Myshakin, Evgeniy

2011-01-01T23:59:59.000Z

268

Astronomy 202: Astrophysical Gas Dynamics LL = Fluid Mechanics by Landau & Lifshitz  

E-Print Network [OSTI]

Astronomy 202: Astrophysical Gas Dynamics LL = Fluid Mechanics by Landau & Lifshitz PP = Plasma Fluid Dynamics by D. J. Tritton You should start by reading the Feynman Lectures Vol II, Ch 40 & 41 (Shu Ch. 1) 2. Equations of Gas Dynamics: neutral ideal fluids (LL Ch. 1; esp. §1,2,5,6,7,8,10; Shu Ch

Wurtele, Jonathan

269

METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST  

SciTech Connect (OSTI)

Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. The work scope drilled and cored a well The Hot Ice No. 1 on Anadarko leases beginning in FY 2003 and completed in 2004. An on-site core analysis laboratory was built and utilized for determining the physical characteristics of the hydrates and surrounding rock. The well was drilled from a new Anadarko Arctic Platform that has a minimal footprint and environmental impact. The final efforts of the project are to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists developing reservoir models. No gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in this report. The Hot Ice No. 1 well was drilled from the surface to a measured depth of 2300 ft. There was almost 100% core recovery from the bottom of surface casing at 107 ft to total depth. Based on the best estimate of the bottom of the methane hydrate stability zone (which used new data obtained from Hot Ice No. 1 and new analysis of data from adjacent wells), core was recovered over its complete range. Approximately 580 ft of porous, mostly frozen, sandstone and 155 of conglomerate were recovered in the Ugnu Formation and approximately 215 ft of porous sandstone were recovered in the West Sak Formation. There were gas shows in the bottom part of the Ugnu and throughout the West Sak. No hydrate-bearing zones were identified either in recovered core or on well logs. The base of the permafrost was found at about 1260 ft. With the exception of the deepest sands in the West Sak and some anomalous thin, tight zones, all sands recovered (after thawing) are unconsolidated with high porosity and high permeability. At 800 psi, Ugnu sands have an average porosity of 39.3% and geometrical mean permeability of 3.7 Darcys. Average grain density is 2.64 g/cc. West Sak sands have an average porosity of 35.5%, geometrical mean permeability of 0.3 Darcys, and average grain density of 2.70 g/cc. There were several 1-2 ft intervals of carbonate-cemented sandstone recovered from the West Sak. These intervals have porosities of only a few percent and very low permeability. On a well log they appear as resistive with a high sonic velocity. In shallow sections of other wells these usually are the only logs available. Given the presence of gas in Hot Ice No. 1, if only resistivity and sonic logs and a mud log had been available, tight sand zones may have been interpreted as containing hydrates. Although this finding does not imply that all previously mapped hydrate zones are merely tight sands, it does add a note of caution to the practice of interpreting the presence of hydrates from old well information. The methane hydrate stability zone below the Hot Ice No. 1 location includes thick sections of sandstone and conglomerate which would make excellent reservoir rocks for hydrates and below the permafrost zone shallow gas. The Ugnu formation comprises a more sand-rich section than does the West Sak formation, and the Ugnu sands when cleaned and dried are slightly more porous and significantly more permeable than the West Sak.

Richard Sigal; Kent Newsham; Thomas Williams; Barry Freifeld; Timothy Kneafsey; Carl Sondergeld; Shandra Rai; Jonathan Kwan; Stephen Kirby; Robert Kleinberg; Doug Griffin

2005-02-01T23:59:59.000Z

270

Gas Dynamic Effects On Laser Cut Quality Kai Chen, Y. Lawrence Yao, and Vijay Modi  

E-Print Network [OSTI]

Gas Dynamic Effects On Laser Cut Quality Kai Chen, Y. Lawrence Yao, and Vijay Modi Department are very sensitive to gas jet pressure and nozzle standoff distance. Do a high gas pressure and a small shows the same behavior (i.e., discontinuity as gas pressure and standoff change

Yao, Y. Lawrence

271

Study of gas flow dynamics in porous and granular media with laser-polarized ą˛?Xe NMR  

E-Print Network [OSTI]

This thesis presents Nuclear Magnetic Resonance (NMR) studies of gas flow dynamics in porous and granular media by using laser-polarized ą˛?Xe . Two different physical processes, the gas transport in porous rock cores and ...

Wang, Ruopeng, 1972-

2005-01-01T23:59:59.000Z

272

Relation Between the Widom Line and the Dynamic Crossover in Bulk Water and in Protein Hydration Water  

E-Print Network [OSTI]

are the derivatives of the state functions with respect to temperature [e.g., isobaric heat capacity CP (H/T)P ] have displaying a liquid-liquid critical point, the relation between changes in dynamic and thermodynamic anomalies arising from the presence of the liquid-liquid critical point. We find a correlation between

Stanley, H. Eugene

273

Methane Hydrate Field Program  

SciTech Connect (OSTI)

This final report document summarizes the activities undertaken and the output from three primary deliverables generated during this project. This fifteen month effort comprised numerous key steps including the creation of an international methane hydrate science team, determining and reporting the current state of marine methane hydrate research, convening an international workshop to collect the ideas needed to write a comprehensive Marine Methane Hydrate Field Research Plan and the development and publication of that plan. The following documents represent the primary deliverables of this project and are discussed in summary level detail in this final report. • Historical Methane Hydrate Project Review Report • Methane Hydrate Workshop Report • Topical Report: Marine Methane Hydrate Field Research Plan • Final Scientific/Technical Report

None

2013-12-31T23:59:59.000Z

274

Phase I (CATTS Theory), Phase II (Milne Point), Phase III (Hydrate Ridge)  

SciTech Connect (OSTI)

This study introduces a new type of â??cumulative seismic attributeâ?ť (CATT) which quantifies gas hydrates resources in Hydrate Ridge offshore Oregon. CATT is base on case-specific transforms that portray hydrated reservoir properties. In this study we used a theoretical rock physics model to correct measured velocity log data.

None

2009-10-31T23:59:59.000Z

275

Multi-Symplectic Lagrangian, One-Dimensional Gas Dynamics  

E-Print Network [OSTI]

The equations of Lagrangian, ideal, one-dimensional (1D), compressible gas dynamics are written in a multi-symplectic form using the Lagrangian mass coordinate $m$ and time $t$ as independent variables, and in which the Eulerian position of the fluid element $x=x(m,t)$ is one of the dependent variables. This approach differs from the Eulerian, multi-symplectic approach using Clebsch variables. Lagrangian constraints are used to specify equations for $x_m$, $x_t$ and $S_t$ consistent with the Lagrangian map, where $S$ is the entropy of the gas. We require $S_t=0$ corresponding to advection of the entropy $S$ with the flow. We show that the Lagrangian Hamiltonian equations are related to the de Donder-Weyl multi-momentum formulation. The pullback conservation laws and the symplecticity conservation laws are discussed. The pullback conservation laws correspond to invariance of the action with respect to translations in time (energy conservation) and translations in $m$ in Noether's theorem. The conservation law due to $m$-translation invariance gives rise to a novel nonlocal conservation law involving the Clebsch variable $r$ used to impose $\\partial S(m,t)/\\partial t=0$. Translation invariance with respect to $x$ in Noether's theorem is associated with momentum conservation. We obtain the Cartan-Poincar\\'e form for the system, and use it to obtain a closed ideal of two-forms representing the equation system.

G. M. Webb

2015-02-03T23:59:59.000Z

276

Multi-Symplectic Lagrangian, One-Dimensional Gas Dynamics  

E-Print Network [OSTI]

The equations of Lagrangian, ideal, one-dimensional (1D), compressible gas dynamics are written in a multi-symplectic form using the Lagrangian mass coordinate $m$ and time $t$ as independent variables, and in which the Eulerian position of the fluid element $x=x(m,t)$ is one of the dependent variables. This approach differs from the Eulerian, multi-symplectic approach using Clebsch variables. Lagrangian constraints are used to specify equations for $x_m$, $x_t$ and $S_t$ consistent with the Lagrangian map, where $S$ is the entropy of the gas. We require $S_t=0$ corresponding to advection of the entropy $S$ with the flow. We show that the Lagrangian Hamiltonian equations are related to the de Donder-Weyl multi-momentum formulation. The pullback conservation laws and the symplecticity conservation laws are discussed. The pullback conservation laws correspond to invariance of the action with respect to translations in time (energy conservation) and translations in $m$ in Noether's theorem. The conservation law due to $m$-translation invariance gives rise to a novel nonlocal conservation law involving the Clebsch variable $r$ used to impose $\\partial S(m,t)/\\partial t=0$. Translation invariance with respect to $x$ in Noether's theorem is associated with momentum conservation. We obtain the Cartan-Poincar\\'e form for the system, and use it to obtain a closed ideal of two-forms representing the equation system.

G. M. Webb

2014-08-18T23:59:59.000Z

277

Dynamics of a Massive Piston in an Ideal Gas N. Chernov1,4  

E-Print Network [OSTI]

Dynamics of a Massive Piston in an Ideal Gas N. Chernov1,4 , J. L. Lebowitz2,4 , and Ya. Sinai3 January 1, 2003 Abstract We study a dynamical system consisting of a massive piston in a cubical con- tainer of large size L filled with an ideal gas. The piston has mass M L2 and undergoes elastic

278

Methane hydrate distribution from prolonged and repeated formation in natural and compacted sand samples: X-ray CT observations  

SciTech Connect (OSTI)

To study physical properties of methane gas hydrate-bearing sediments, it is necessary to synthesize laboratory samples due to the limited availability of cores from natural deposits. X-ray computed tomography (CT) and other observations have shown gas hydrate to occur in a number of morphologies over a variety of sediment types. To aid in understanding formation and growth patterns of hydrate in sediments, methane hydrate was repeatedly formed in laboratory-packed sand samples and in a natural sediment core from the Mount Elbert Stratigraphic Test Well. CT scanning was performed during hydrate formation and decomposition steps, and periodically while the hydrate samples remained under stable conditions for up to 60 days. The investigation revealed the impact of water saturation on location and morphology of hydrate in both laboratory and natural sediments during repeated hydrate formations. Significant redistribution of hydrate and water in the samples was observed over both the short and long term.

Rees, E.V.L.; Kneafsey, T.J.; Seol, Y.

2010-07-01T23:59:59.000Z

279

Scaling Dynamics of a Massive Piston in a Cube Filled With Ideal Gas: Exact Results  

E-Print Network [OSTI]

Scaling Dynamics of a Massive Piston in a Cube Filled With Ideal Gas: Exact Results N. Chernov 1 of a piston in a cubical container of large size L filled with an ideal gas. The piston has mass M # L 2 heuristically that the motion of the piston and the one particle distribution of the gas satisfy autonomous

280

Noble gas temperature control of metal clusters: A molecular dynamics study  

E-Print Network [OSTI]

Noble gas temperature control of metal clusters: A molecular dynamics study Jan Westergren a noble gas atmosphere. The simulations are performed using a many-body interaction scheme for the intra-cluster potential, while a pairwise Lennard-Jones potential is used to model the interaction between the noble gas

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Ambient gas effects on the dynamics of laser-produced tin plume expansion  

E-Print Network [OSTI]

Ambient gas effects on the dynamics of laser-produced tin plume expansion S. S. Harilal,a Beau O in the development of an extreme ultraviolet lithographic light source. An ambient gas that is transparent to 13.5 nm and deceleration of plume species, the addition of ambient gas leads to other events such as double peak formation

Tillack, Mark

282

Contributed papers Study of gas-fluidization dynamics with laser-polarized 129  

E-Print Network [OSTI]

Gas fluidization is a process in which solid particles experience fluid-like suspension in an upward. Bubbles, or void spaces with volume much larger than that of a single particle, emerge when the gas flowContributed papers Study of gas-fluidization dynamics with laser-polarized 129 Xe Ruopeng Wanga

Walsworth, Ronald L.

283

Ab initio investigation of the first hydration shell of protonated glycine  

SciTech Connect (OSTI)

The first hydration shell of the protonated glycine is built up using Monte Carlo multiple minimum conformational search analysis with the MMFFs force field. The potential energy surfaces of the protonated glycine and its hydration complexes with up to eight water molecules have been scanned and the energy-minimized structures are predicted using the ab initio calculations. First, three favorable structures of protonated glycine were determined, and the micro-hydration processes showed that water can significantly stabilize the unstable conformers, and then their first hydration shells were established. Finally, we found that seven water molecules are required to fully hydrate the first hydration shell for the most stable conformer of protonated glycine. In order to analyse the hydration process, the dominant hydration sites located around the ammonium and carboxyl groups are studied carefully and systemically. The results indicate that, water molecules hydrate the protonated glycine in an alternative dynamic hydration process which is driven by the competition between different hydration sites. The first three water molecules are strongly attached by the ammonium group, while only the fourth water molecule is attached by the carboxyl group in the ultimate first hydration shell of the protonated glycine. In addition, the first hydration shell model has predicted most identical structures and a reasonable accord in hydration energy and vibrational frequencies of the most stable conformer with the conductor-like polarizable continuum model.

Wei, Zhichao; Chen, Dong, E-mail: dongchen@henu.edu.cn, E-mail: boliu@henu.edu.cn; Zhao, Huiling; Li, Yinli; Zhu, Jichun; Liu, Bo, E-mail: dongchen@henu.edu.cn, E-mail: boliu@henu.edu.cn [Institute of Photo-Biophysics, Physics and Electronics Department, Henan University, 475004 Kaifeng (China)] [Institute of Photo-Biophysics, Physics and Electronics Department, Henan University, 475004 Kaifeng (China)

2014-02-28T23:59:59.000Z

284

Investigating the Metastability of Clathrate Hydrates for Energy Storage  

SciTech Connect (OSTI)

Important breakthrough discoveries have been achieved from the DOE award on the key processes controlling the synthesis and structure-property relations of clathrate hydrates, which are critical to the development of clathrate hydrates as energy storage materials. Key achievements include: (i) the discovery of key clathrate hydrate building blocks (stable and metastable) leading to clathrate hydrate nucleation and growth; (ii) development of a rapid clathrate hydrate synthesis route via a seeding mechanism; (iii) synthesis-structure relations of H2 + CH4/CO2 binary hydrates to control thermodynamic requirements for energy storage and sequestration applications; (iv) discovery of a new metastable phase present during clathrate hydrate structural transitions. The success of our research to-date is demonstrated by the significant papers we have published in high impact journals, including Science, Angewandte Chemie, J. Am. Chem. Soc. Intellectual Merits of Project Accomplishments: The intellectual merits of the project accomplishments are significant and transformative, in which the fundamental coupled computational and experimental program has provided new and critical understanding on the key processes controlling the nucleation, growth, and thermodynamics of clathrate hydrates containing hydrogen, methane, carbon dioxide, and other guest molecules for energy storage. Key examples of the intellectual merits of the accomplishments include: the first discovery of the nucleation pathways and dominant stable and metastable structures leading to clathrate hydrate formation; the discovery and experimental confirmation of new metastable clathrate hydrate structures; the development of new synthesis methods for controlling clathrate hydrate formation and enclathration of molecular hydrogen. Broader Impacts of Project Accomplishments: The molecular investigations performed in this project on the synthesis (nucleation & growth)-structure-stability relations of clathrate hydrate systems are pivotal in the fundamental understanding of crystalline clathrate hydrates and the discovery of new clathrate hydrate properties and novel materials for a broad spectrum of energy applications, including: energy storage (hydrogen, natural gas); carbon dioxide sequestration; controlling hydrate formation in oil/gas transportation in subsea pipelines. The Project has also enabled the training of undergraduate, graduate and postdoctoral students in computational methods, molecular spectroscopy and diffraction, and measurement methods at extreme conditions of high pressure and low temperature.

Koh, Carolyn Ann [Colorado School of Mines

2014-11-18T23:59:59.000Z

285

Project EARTH-13-SHELL2: Controls on the distribution of methane hydrates in sedimentary basins  

E-Print Network [OSTI]

unconventional gas exploration, since they host a significant fraction of the world's gas reserves. This project dominant in given contexts, so that future prediction of hydrate reserves is more accurate, and hydrate, nodular), and these have different implications for reserve estimations and for geohazards. For example

Henderson, Gideon

286

Experimental study on the formation and dissociation conditions of methane hydrates in porous media  

E-Print Network [OSTI]

hydrates formed by methane gas and pure water in porous media. Methane gas hydrates were formed in a cell packed with 0.177-mm (0.007 in) diameter single sand (U.S. Sieve Series Designation Mesh No. 80) and 0.420-mm (0.017 in) diameter single sand (U...

Jung, Woodong

2002-01-01T23:59:59.000Z

287

Four Critical Needs to Change the Hydrate Energy Paradigm from Assessment to Production: The 2007 Report to Congress by the U.S. Federal methane Hydrate Advisory Committee  

SciTech Connect (OSTI)

This work summarizes a two-year study by the U.S. Federal Methane Hydrate Advisory Committee recommending the future needs for federally-supported hydrate research. The Report was submitted to the US Congress on August 14, 2007 and includes four recommendations regarding (a) permafrost hydrate production testing, (b) marine hydrate viability assessment (c) climate effect of hydrates, and (d) international cooperation. A secure supply of natural gas is a vital goal of the U.S. national energy policy because natural gas is the cleanest and most widely used of all fossil fuels. The inherent cleanliness of natural gas, with the lowest CO2 emission per unit of heat energy of any fossil fuel, means substituting gas for coal and fuel oil will reduce emissions that can exacerbate the greenhouse effect. Both a fuel and a feedstock, a secure and reasonably priced supply of natural gas is important to industry, electric power generators, large and small commercial enterprises, and homeowners. Because each volume of solid gas hydrate contains as much as 164 standard volumes of methane, hydrates can be viewed as a concentrated form of natural gas equivalent to compressed gas but less concentrated than liquefied natural gas (LNG). Natural hydrate accumulations worldwide are estimated to contain 700,000 TCF of natural gas, of which 200,000 TCF are located within the United States. Compared with the current national annual consumption of 22 TCF, this estimate of in-place gas in enormous. Clearly, if only a fraction of the hydrated methane is recoverable, hydrates could constitute a substantial component of the future energy portfolio of the Nation (Figure 1). However, recovery poses a major technical and commercial challenge. Such numbers have sparked interest in natural gas hydrates as a potential, long-term source of energy, as well as concerns about any potential impact the release of methane from hydrates might have on the environment. Energy-hungry countries such as India and Japan are outspending the United States on hydrate science and engineering R&D by a factor of 10, and may bring this resource to market as much as a decade before the United States.

Mahajan,D.; Sloan, D.; Brewer, P.; Dutta, N.; Johnson, A.; Jones, E.; Juenger, K.; Kastner, M.; Masutani, S.; Swenson, R.; Whelan, J.; Wilson, s.; Woolsey, R.

2009-03-11T23:59:59.000Z

288

Method for controlling clathrate hydrates in fluid systems  

DOE Patents [OSTI]

Discussed is a process for preventing clathrate hydrate masses from impeding the flow of fluid in a fluid system. An additive is contacted with clathrate hydrate masses in the system to prevent those clathrate hydrate masses from impeding fluid flow. The process is particularly useful in the natural gas and petroleum production, transportation and processing industry where gas hydrate formation can cause serious problems. Additives preferably contain one or more five member, six member and/or seven member cyclic chemical groupings. Additives include poly(N-vinyl-2-pyrrolidone) and hydroxyethylcellulose, either in combination or alone. Additives can also contain multiple cyclic chemical groupings having different size rings. One such additive is sold under the name Gaffix VC-713.

Sloan, E.D. Jr.

1995-07-11T23:59:59.000Z

289

Method for controlling clathrate hydrates in fluid systems  

DOE Patents [OSTI]

Discussed is a process for preventing clathrate hydrate masses from impeding the flow of fluid in a fluid system. An additive is contacted with clathrate hydrate masses in the system to prevent those clathrate hydrate masses from impeding fluid flow. The process is particularly useful in the natural gas and petroleum production, transportation and processing industry where gas hydrate formation can cause serious problems. Additives preferably contain one or more five member, six member and/or seven member cyclic chemical groupings. Additives include poly(N-vinyl-2-pyrrolidone) and hydroxyethylcellulose, either in combination or alone. Additives can also contain multiple cyclic chemical groupings having different size rings. One such additive is sold under the name Gaffix VC-713.

Sloan, Jr., Earle D. (Golden, CO)

1995-01-01T23:59:59.000Z

290

Gas dynamics in high-luminosity polarized 3He targets using diffusion and convection  

E-Print Network [OSTI]

The dynamics of the movement of gas is discussed for two-chambered polarized 3He target cells of the sort that have been used successfully for many electron-scattering experiments. A detailed analysis is presented showing ...

Kelleher, Aidan Michael

291

Analysis of condensate banking dynamics in a gas condensate reservoir under different injection schemes  

E-Print Network [OSTI]

condensate reservoir under natural depletion, and injection of methane, injection of carbon dioxide, produced gas recycling and water injection. To monitor the condensate banking dynamics near the wellbore area, such as oil saturation and compositional...

Sandoval Rodriguez, Angelica Patricia

2002-01-01T23:59:59.000Z

292

Study on small-strain behaviours of methane hydrate sandy sediments using discrete element method  

SciTech Connect (OSTI)

Methane hydrate bearing soil has attracted increasing interest as a potential energy resource where methane gas can be extracted from dissociating hydrate-bearing sediments. Seismic testing techniques have been applied extensively and in various ways, to detect the presence of hydrates, due to the fact that hydrates increase the stiffness of hydrate-bearing sediments. With the recognition of the limitations of laboratory and field tests, wave propagation modelling using Discrete Element Method (DEM) was conducted in this study in order to provide some particle-scale insights on the hydrate-bearing sandy sediment models with pore-filling and cementation hydrate distributions. The relationship between shear wave velocity and hydrate saturation was established by both DEM simulations and analytical solutions. Obvious differences were observed in the dependence of wave velocity on hydrate saturation for these two cases. From the shear wave velocity measurement and particle-scale analysis, it was found that the small-strain mechanical properties of hydrate-bearing sandy sediments are governed by both the hydrate distribution patterns and hydrate saturation.

Yu Yanxin; Cheng Yipik [Department of Civil, Environmental and Geomatic Engineering, University College London (UCL), Gower Street, London, WC1E 6BT (United Kingdom); Xu Xiaomin; Soga, Kenichi [Geotechnical and Environmental Research Group, Department of Engineering, University of Cambridge, Trumpington Street, Cambridge, CB2 1PZ (United Kingdom)

2013-06-18T23:59:59.000Z

293

(Astro)Physics 343 Lecture # 8: Green Bank trip + gas dynamics  

E-Print Network [OSTI]

matter (i.e., dark matter). #12; A heretical alternative? A few bold souls have pointed out that once/T. #12; Gas dynamics: a Keplerian example From Herrnstein et al. (1999): water masers tracing orbital, based on the central concentration of luminous matter (stars and gas): #12; Rotation curves

Baker, Andrew J.

294

(Astro)Physics 343 Lecture # 8: Green Bank trip; gas dynamics  

E-Print Network [OSTI]

matter (i.e., dark matter). #12; A heretical alternative? A few bold souls have pointed out that once/T. #12; Gas dynamics: a Keplerian example From Herrnstein et al. (1999): water masers tracing orbital, based on the central concentration of luminous matter (stars and gas): #12; Rotation curves

Baker, Andrew J.

295

Scaling Dynamics of a Massive Piston in a Cube Filled With Ideal Gas: Exact Results  

E-Print Network [OSTI]

Scaling Dynamics of a Massive Piston in a Cube Filled With Ideal Gas: Exact Results N. Chernov1 65th birthday Abstract We continue the study of the time evolution of a system consisting of a piston in a cubical container of large size L filled with an ideal gas. The piston has mass M L2 and undergoes

Lebowitz, Joel

296

Dynamics of the UK Natural Gas Industry: System Dynamics Modelling and Long-Term Energy Policy Analysis  

E-Print Network [OSTI]

www.eprg.group.cam.ac.uk E P R G W O R K IN G P A P E R N O N -T E C H N IC A L S U M M A R Y DYNAMICS OF THE UK NATURAL GAS INDUSTRY: SYSTEM DYNAMICS MODELLING AND LONG-TERM ENERGY POLICY ANALYSIS EPRG Working Paper 0913... Cambridge Working Paper in Economics 0922 Kong Chyong Chi , David M. Reiner and William J. Nuttall The UK offshore natural gas and oil industry has a long and successful history and has been said to represent the pride of UK...

Chi, K C; Reiner, David; Nuttall, William J

297

Terr. Atmos. Ocean. Sci., Vol. 17, No. 4, 933-950, December 2006 Methane Venting in Gas Hydrate Potential Area Offshore of SW  

E-Print Network [OSTI]

Potential Area Offshore of SW Taiwan: Evidence of Gas Analysis of Water Column Samples Tsanyao Frank Yang 1 areas offshore of SW Taiwan for analysis of dissolved gases. Some these samples show unusually high-shore and offshore of southwestern Taiwan (e.g., Chow et al. 2000; Yang et al. 2004; Chiu et al. 2006). The gases

Lin, Andrew Tien-Shun

298

Molecular dynamics simulation of nanoporous graphene for selective gas separation  

E-Print Network [OSTI]

Graphene with sub-nanometer sized pores has the potential to act as a filter for gas separation with considerable efficiency gains compared to traditional technologies. Nanoporous graphene membranes are expected to yield ...

Au, Harold (Harold S.)

2012-01-01T23:59:59.000Z

299

Dynamics of inelastic and reactive gas-surface collisions  

SciTech Connect (OSTI)

The dynamics of inelastic and reactive collisions in atomic beam-surface scattering are presented. The inelastic scattering of hyperthermal rare gaseous atoms from three alkali halide surfaces (LiF, NaCl, GI)was studied to understand mechanical energy transfer in unreactive systems. The dynamics of the chemical reaction in the scattering of H(D) atoms from the surfaces of LIF(001) and the basal plane of graphite were also studied.

Smoliar, L.A.

1995-04-01T23:59:59.000Z

300

Thermal dissociation behavior and dissociation enthalpies of methane-carbon dioxide mixed hydrates  

SciTech Connect (OSTI)

Replacement of methane with carbon dioxide in hydrate has been proposed as a strategy for geologic sequestration of carbon dioxide (CO{sub 2}) and/or production of methane (CH{sub 4}) from natural hydrate deposits. This replacement strategy requires a better understanding of the thermodynamic characteristics of binary mixtures of CH{sub 4} and CO{sub 2} hydrate (CH{sub 4}-CO{sub 2} mixed hydrates), as well as thermophysical property changes during gas exchange. This study explores the thermal dissociation behavior and dissociation enthalpies of CH{sub 4}-CO{sub 2} mixed hydrates. We prepared CH{sub 4}-CO{sub 2} mixed hydrate samples from two different, well-defined gas mixtures. During thermal dissociation of a CH{sub 4}-CO{sub 2} mixed hydrate sample, gas samples from the head space were periodically collected and analyzed using gas chromatography. The changes in CH{sub 4}-CO{sub 2} compositions in both the vapor phase and hydrate phase during dissociation were estimated based on the gas chromatography measurements. It was found that the CO{sub 2} concentration in the vapor phase became richer during dissociation because the initial hydrate composition contained relatively more CO{sub 2} than the vapor phase. The composition change in the vapor phase during hydrate dissociation affected the dissociation pressure and temperature; the richer CO{sub 2} in the vapor phase led to a lower dissociation pressure. Furthermore, the increase in CO{sub 2} concentration in the vapor phase enriched the hydrate in CO{sub 2}. The dissociation enthalpy of the CH{sub 4}-CO{sub 2} mixed hydrate was computed by fitting the Clausius-Clapeyron equation to the pressure-temperature (PT) trace of a dissociation test. It was observed that the dissociation enthalpy of the CH{sub 4}-CO{sub 2} mixed hydrate lays between the limiting values of pure CH{sub 4} hydrate and CO{sub 2} hydrate, increasing with the CO{sub 2} fraction in the hydrate phase.

Kwon, T.H.; Kneafsey, T.J.; Rees, E.V.L.

2011-02-15T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Dissipative dynamics of a kink state in a Bose-condensed gas  

E-Print Network [OSTI]

We develop a theory of dissipative dynamics of a kink state in a finite-temperature Bose-condensed gas. We find that due to the interaction with the thermal cloud the kink state accelerates towards the velocity of sound and continuously transforms to the ground-state condensate. We calculate the life-time of a kink state in a trapped gas and discuss possible experimental implications.

P. O. Fedichev; A. E. Muryshev; G. V. Shlyapnikov

1999-05-18T23:59:59.000Z

302

Impact of Fuel Interchangeability on dynamic Instabilities in Gas Turbine Engines  

SciTech Connect (OSTI)

Modern, low NOx emitting gas turbines typically utilize lean pre-mixed (LPM) combustion as a means of achieving target emissions goals. As stable combustion in LPM systems is somewhat intolerant to changes in operating conditions, precise engine tuning on a prescribed range of fuel properties is commonly performed to avoid dynamic instabilities. This has raised concerns regarding the use of imported liquefied natural gas (LNG) and natural gas liquids (NGL’s) to offset a reduction in the domestic natural gas supply, which when introduced into the pipeline could alter the fuel BTU content and subsequently exacerbate problems such as combustion instabilities. The intent of this study is to investigate the sensitivity of dynamically unstable test rigs to changes in fuel composition and heat content. Fuel Wobbe number was controlled by blending methane and natural gas with various amounts of ethane, propane and nitrogen. Changes in combustion instabilities were observed, in both atmospheric and pressurized test rigs, for fuels containing high concentrations of propane (> 62% by vol). However, pressure oscillations measured while operating on typical “LNG like” fuels did not appear to deviate significantly from natural gas and methane flame responses. Mechanisms thought to produce changes in the dynamic response are discussed.

Ferguson, D.H.; Straub, D.L.; Richards, G.A.; Robey, E.H.

2007-03-01T23:59:59.000Z

303

Physics 343 Lecture # 8: Green Bank trip; gas dynamics  

E-Print Network [OSTI]

rotation curves, implying the existence of additional nonluminous matter (i.e., dark matter). #12, while blue shows mass based on weak lensing (apparently, mostly dark matter that is not "collisional dynamics: a Keplerian example From Herrnstein et al. (1999): water masers tracing orbital motions around

Baker, Andrew J.

304

TOUGH+Hydrate v1.0 User's Manual: A Code for the Simulation of System Behavior in Hydrate-Bearing Geologic Media  

SciTech Connect (OSTI)

TOUGH+HYDRATE v1.0 is a new code for the simulation of the behavior of hydrate-bearing geologic systems. By solving the coupled equations of mass and heat balance, TOUGH+HYDRATE can model the non-isothermal gas release, phase behavior and flow of fluids and heat under conditions typical of common natural CH{sub 4}-hydrate deposits (i.e., in the permafrost and in deep ocean sediments) in complex geological media at any scale (from laboratory to reservoir) at which Darcy's law is valid. TOUGH+HYDRATE v1.0 includes both an equilibrium and a kinetic model of hydrate formation and dissociation. The model accounts for heat and up to four mass components, i.e., water, CH{sub 4}, hydrate, and water-soluble inhibitors such as salts or alcohols. These are partitioned among four possible phases (gas phase, liquid phase, ice phase and hydrate phase). Hydrate dissociation or formation, phase changes and the corresponding thermal effects are fully described, as are the effects of inhibitors. The model can describe all possible hydrate dissociation mechanisms, i.e., depressurization, thermal stimulation, salting-out effects and inhibitor-induced effects. TOUGH+HYDRATE is the first member of TOUGH+, the successor to the TOUGH2 [Pruess et al., 1991] family of codes for multi-component, multiphase fluid and heat flow developed at the Lawrence Berkeley National Laboratory. It is written in standard FORTRAN 95, and can be run on any computational platform (workstation, PC, Macintosh) for which such compilers are available.

Moridis, George; Moridis, George J.; Kowalsky, Michael B.; Pruess, Karsten

2008-03-01T23:59:59.000Z

305

Investigation of gain kinetics in a CO gas dynamic laser  

SciTech Connect (OSTI)

A detailed experimental investigation of small-signal gain in a CO gasdynamic laser, produced in a shock tunnel is presented. Gains of the P/sub 7/(3) transition were measured at a distance 44 cm downstream from the nozzle throat for various CO--Ar and CO--N/sub 2/--Ar mixtures at stagnation temperatures of 1800/sup 0/--3800 /sup 0/K and stagnation pressures of 18--40 atm. Optimum gas temperatures and compositions were observed. Laser oscillations were observed simultaneously in two cavities located at 44 and 56 cm downstream from the nozzle throat. The experimental data on gain have been compared with a numerical model. A quantitatively good argeement between calculations and experiments was found which permits the utilization of the mathematical model for a better understanding of the processes involved in the laser operation. Small signal gains and multi-line laser power outputs were calculated along the nozzle for various initial conditions. Calculations indicate that maximum gain and maximum power occur for P/sub 3/(4)-P/sub 5/(4) lines at a stagnation temperature of about 3000 /sup 0/K and a gas composition of CO:Ar = 20:80.

Stricker, J.; Tilleman, M.

1982-06-01T23:59:59.000Z

306

Carbon and nitrogen dynamics in bioenergy ecosystems: 2. Potential greenhouse gas emissions and global  

E-Print Network [OSTI]

Carbon and nitrogen dynamics in bioenergy ecosystems: 2. Potential greenhouse gas emissions) from bioenergy ecosystems with a biogeochemical model AgTEM, assuming maize (Zea mays L.), switchgrass haĂ?1 yrĂ?1 . Among all three bioenergy crops, Miscanthus is the most biofuel productive and the least

Zhuang, Qianlai

307

(Astro)Physics 343 Lecture # 8: Green Bank trip; gas dynamics  

E-Print Network [OSTI]

the existence of additional nonluminous matter (i.e., dark matter). #12; A heretical alternative? A few bold on weak lensing (apparently, mostly dark matter that is not "collisional"). #12; Inclination's third law for v = 2R/T. #12; Gas dynamics: a Keplerian example From Herrnstein et al. (1999): water

Baker, Andrew J.

308

Dynamics of a Massive Piston in an Ideal Gas: Oscillatory Motion and Approach to Equilibrium  

E-Print Network [OSTI]

Dynamics of a Massive Piston in an Ideal Gas: Oscillatory Motion and Approach to Equilibrium N confined to a cube of size L3 divided into two parts by a piston with mass ML L2 which can only move and a stationary piston, we find that (a) after an initial quiescent period the system becomes unstable

Chernov, Nikolai

309

Dynamics of a Massive Piston in an Ideal Gas: Oscillatory Motion and Approach to Equilibrium  

E-Print Network [OSTI]

Dynamics of a Massive Piston in an Ideal Gas: Oscillatory Motion and Approach to Equilibrium N confined to a cube of size L 3 divided into two parts by a piston with mass ML # L 2 which can only move and a stationary piston, we find that (a) after an initial quiescent period the system becomes unstable

310

Study of Gas Flow Dynamics in Porous and Granular Media with Laser-Polarized 129  

E-Print Network [OSTI]

Abstract This thesis presents Nuclear Magnetic Resonance (NMR) studies of gas flow dynamics in porous in porous rock cores and the mass exchanges between different phases in fluidized granular systems, were-emulsion exchange and emulsion-adsorption exchange in a fluidized bed are two processes crucial to the efficiency

Walsworth, Ronald L.

311

Flow analysis and nozzle-shape optimization for the cold-gas dynamic-spray process  

E-Print Network [OSTI]

Flow analysis and nozzle-shape optimization for the cold-gas dynamic-spray process M Grujicic1*, W, maximizes the acceleration of the particles. Furthermore, it is found that if the cold-spray nozzle, a significant increase in the average velocity of the particles at the nozzle exit can be obtained

Grujicic, Mica

312

Bubble coalescence dynamics and supersaturation in electrolytic gas evolution  

SciTech Connect (OSTI)

The apparatus and procedures developed in this research permit the observation of electrolytic bubble coalescence, which heretofore has not been possible. The influence of bubble size, electrolyte viscosity, surface tension, gas type, and pH on bubble coalescence was examined. The Navier-Stokes equations with free surface boundary conditions were solved numerically for the full range of experimental variables that were examined. Based on this study, the following mechanism for bubble coalescence emerges: when two gas bubbles coalesce, the surface energy decreases as the curvature and surface area of the resultant bubble decrease, and the energy is imparted into the surrounding liquid. The initial motion is driven by the surface tension and slowed by the inertia and viscosity of the surrounding fluid. The initial velocity of the interface is approximately proportional to the square root of the surface tension and inversely proportional to the square root of the bubble radius. Fluid inertia sustains the oblate/prolate oscillations of the resultant bubble. The period of the oscillations varies with the bubble radius raised to the 3/2 power and inversely with the square root of the surface tension. Viscous resistance dampens the oscillations at a rate proportional to the viscosity and inversely proportional to the square of the bubble radius. The numerical simulations were consistent with most of the experimental results. The differences between the computed and measured saddle point decelerations and periods suggest that the surface tension in the experiments may have changed during each run. By adjusting the surface tension in the simulation, a good fit was obtained for the 150-{micro}m diameter bubbles. The simulations fit the experiments on larger bubbles with very little adjustment of surface tension. A more focused analysis should be done to elucidate the phenomena that occur in the receding liquid film immediately following rupture.

Stover, R.L. [Univ. of California, Berkeley, CA (United States). Dept. of Chemical Engineering]|[Lawrence Berkeley National Lab., CA (United States). Energy and Environment Div.

1996-08-01T23:59:59.000Z

313

Abstract The concurrent goals of cement hydration are to percolate (bridge) the original  

E-Print Network [OSTI]

Cement hydration Ă? Low temperature calorimetry Ă? Microstructure Ă? Percolation Ă? Porosity Ă? Rheology Ă?, however, cement-based materials exhibit a highly dynamic (micro)structure that is extremely sen- sitive. Because many of the cement hydration prod- ucts form around the initial cement clinker par- ticles

Bentz, Dale P.

314

methane hydrate science plan-final.indd  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

2013 Principal Authors: Consor um for Ocean Leadership and the Methane Hydrate Project Science Team December 2013 DOE Award Number: DE-FE0010195 Project Title: Methane Hydrate...

315

Laboratory measurements on core-scale sediment/hydrate samples topredice reservoir behavior  

SciTech Connect (OSTI)

Measurements on hydrate-bearing laboratory and field samplesare necessary in order to provide realistic bounds on parameters used innumerically modeling the production of natural gas from hydrate-bearingreservoirs. The needed parameters include thermal conductivity,permeability, relative permeability-saturation(s) relationships, andcapillary pressure-saturation(s) relationships. We have developed atechnique to make hydrate-bearing samples ranging in scale from coreplug-size to core-size in the laboratory to facilitate making thesemeasurements. In addition to pressure and temperature measurements, weuse x-ray computed tomography scanning to provide high-resolution dataproviding insights on processes occurring in our samples. Several methodsare available to make gas hydrates in the laboratory, and we expect thatthe method used to make the hydrate will impact the behavior of thehydrate sample, and the parameters measured.

Kneafsey, Timothy J.; Seol, Yongkoo; Moridis, George J.; Tomutsa,Liviu; Freifeld, Barry M.

2005-11-02T23:59:59.000Z

316

Molecular computations for reactions and phase transitions: applications to protein stabilization, hydrates and catalysis  

E-Print Network [OSTI]

In this work we have made significant contributions in three different areas of interest: therapeutic protein stabilization, thermodynamics of natural gas clathrate-hydrates, and zeolite catalysis. In all three fields, ...

Anderson, Brian J.

317

Production of hydrocarbons from hydrates. [DOE patent application  

DOE Patents [OSTI]

An economical and safe method of producing hydrocarbons (or natural gas) from in situ hydrocarbon-containing hydrates is given. Once started, the method will be self-driven and will continue producing hydrocarbons over an extended period of time (i.e., many days).

McGuire, P.L.

1981-09-08T23:59:59.000Z

318

4, 9931057, 2007 Methane hydrate  

E-Print Network [OSTI]

BGD 4, 993­1057, 2007 Methane hydrate stability and anthropogenic climate change D. Archer Title Discussions Biogeosciences Discussions is the access reviewed discussion forum of Biogeosciences Methane 2007 Correspondence to: D. Archer (d-archer@uchicago.edu) 993 #12;BGD 4, 993­1057, 2007 Methane hydrate

Paris-Sud XI, Université de

319

Physical property changes in hydrate-bearingsediment due to depressurization and subsequent repressurization  

SciTech Connect (OSTI)

Physical property measurements of sediment cores containing natural gas hydrate are typically performed on material exposed at least briefly to non-in situ conditions during recovery. To examine effects of a brief excursion from the gas-hydrate stability field, as can occur when pressure cores are transferred to pressurized storage vessels, we measured physical properties on laboratory-formed sand packs containing methane hydrate and methane pore gas. After depressurizing samples to atmospheric pressure, we repressurized them into the methane-hydrate stability field and remeasured their physical properties. Thermal conductivity, shear strength, acoustic compressional and shear wave amplitudes and speeds are compared between the original and depressurized/repressurized samples. X-ray computed tomography (CT) images track how the gas-hydrate distribution changes in the hydrate-cemented sands due to the depressurization/repressurization process. Because depressurization-induced property changes can be substantial and are not easily predicted, particularly in water-saturated, hydrate-bearing sediment, maintaining pressure and temperature conditions throughout the core recovery and measurement process is critical for using laboratory measurements to estimate in situ properties.

Kneafsey, Timothy; Waite, W.F.; Kneafsey, T.J.; Winters, W.J.; Mason, D.H.

2008-06-01T23:59:59.000Z

320

SAGEEP 2010 Keystone, Colorado http://www.eegs.org ULTRASONIC VELOCITIES IN LABORATORY-FORMED GAS  

E-Print Network [OSTI]

, Colorado School of Mines, Golden, CO Abstract Gas Hydrates are widely distributed in the near surface oceanic or permafrost regions, i.e. in the gas hydrate stability zone. Compressional-wave (p about 700 to 1500 m/s. Gas hydrates were then formed a partially saturated Ottawa sand sample

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Combining Multicomponent Seismic Attributes, New Rock Physics Models, and In Situ Data to Estimate Gas-Hydrate Concentrations in Deep-Water, Near-Seafloor Strata of the Gulf of Mexico  

SciTech Connect (OSTI)

The Bureau of Economic Geology was contracted to develop technologies that demonstrate the value of multicomponent seismic technology for evaluating deep-water hydrates across the Green Canyon area of the Gulf of Mexico. This report describes the methodologies that were developed to create compressional (P-P) and converted-shear (P-SV) images of near-seafloor geology from four-component ocean-bottom-cable (4C OBC) seismic data and the procedures used to integrate P-P and P-SV seismic attributes with borehole calibration data to estimate hydrate concentration across two study areas spanning 16 and 25 lease blocks (or 144 and 225 square miles), respectively. Approximately 200 km of two-dimensional 4C OBC profiles were processed and analyzed over the course of the 3-year project. The strategies we developed to image near-seafloor geology with 4C OBC data are unique, and the paper describing our methodology was peer-recognized with a Best Paper Award by the Society of Exploration Geophysicists in the first year of the project (2006). Among the valuable research findings demonstrated in this report, the demonstrated ability to image deep-water near-seafloor geology with sub-meter resolution using a standard-frequency (10-200 Hz) air gun array on the sea surface and 4C sensors on the seafloor has been the accomplishment that has received the most accolades from professional peers. Our study found that hydrate is pervasive across the two study areas that were analyzed but exists at low concentrations. Although our joint inversion technique showed that in some limited areas, and in some geologic units across those small areas, hydrates occupied up to 40-percent of the sediment pore space, we found that when hydrate was present, hydrate concentration tended to occupy only 10-percent to 20-percent of the pore volume. We also found that hydrate concentration tended to be greater near the base of the hydrate stability zone than it was within the central part of the stability zone.

Bureau of Economic Geology

2009-04-30T23:59:59.000Z

322

SUESS ET AL.: SEA FLOOR METHANE HYDRATES AT HYDRATE RIDGE, CASCADIA MARGIN Sea Floor Methane Hydrates at Hydrate Ridge, Cascadia Margin  

E-Print Network [OSTI]

SUESS ET AL.: SEA FLOOR METHANE HYDRATES AT HYDRATE RIDGE, CASCADIA MARGIN 1 Sea Floor Methane are exposed at the sea floor. A methane-oxidizing bacterial consortium populates the exposures of hydrate; colonies of vent macro-fauna are abundant as well. Discharge of methane from destabilized hydrate

Goldfinger, Chris

323

Dissipative dynamics of a vortex state in a trapped Bose-condensed gas  

E-Print Network [OSTI]

We discuss dissipative dynamics of a vortex state in a trapped Bose-condensed gas at finite temperature and draw a scenario of decay of this state in a static trap. The interaction of the vortex with the thermal cloud transfers energy from the vortex to the cloud and induces the motion of the vortex core to the border of the condensate. Once the vortex reaches the border, it immediately decays through the creation of excitations. We calculate the characteristic life-time of a vortex state and address the question of how the dissipative dynamics of vortices can be studied experimentally.

P. O. Fedichev; G. V. Shlyapnikov

1999-06-15T23:59:59.000Z

324

Variability of the methane trapping in martian subsurface clathrate hydrates  

E-Print Network [OSTI]

Recent observations have evidenced traces of methane CH4 heterogeneously distributed in the martian atmosphere. However, because the lifetime of CH4 in the atmosphere of Mars is estimated to be around 300-600 years on the basis of photochemistry, its release from a subsurface reservoir or an active primary source of methane have been invoked in the recent literature. Among the existing scenarios, it has been proposed that clathrate hydrates located in the near subsurface of Mars could be at the origin of the small quantities of the detected CH4. Here, we accurately determine the composition of these clathrate hydrates, as a function of temperature and gas phase composition, by using a hybrid statistical thermodynamic model based on experimental data. Compared to other recent works, our model allows us to calculate the composition of clathrate hydrates formed from a more plausible composition of the martian atmosphere by considering its main compounds, i.e. carbon dioxyde, nitrogen and argon, together with methane. Besides, because there is no low temperature restriction in our model, we are able to determine the composition of clathrate hydrates formed at temperatures corresponding to the extreme ones measured in the polar caps. Our results show that methane enriched clathrate hydrates could be stable in the subsurface of Mars only if a primitive CH4-rich atmosphere has existed or if a subsurface source of CH4 has been (or is still) present.

Caroline Thomas; Olivier Mousis; Sylvain Picaud; Vincent Ballenegger

2008-10-23T23:59:59.000Z

325

Carbon dioxide, argon, nitrogen and methane clathrate hydrates:1 thermodynamic modelling, investigation of their stability in Martian2  

E-Print Network [OSTI]

1 Carbon dioxide, argon, nitrogen and methane clathrate hydrates:1 thermodynamic modelling-4Dec2012 #12;3 Keywords: Mars, clathrate hydrate, nitrogen, carbon dioxide, argon, methane, equilibrium and allows to simulating a Martian gas, CO2 dominated (95.3%) plus nitrogen6 (2.7%) and argon (2

Paris-Sud XI, Université de

326

Auto-oligomerization and hydration of pyrrole revealed by x-ray absorption spectroscopy  

SciTech Connect (OSTI)

Near edge x-ray absorption fine structure (NEXAFS) spectra have been measured at the carbon and nitrogen K-edges of the prototypical aromatic molecule, pyrrole, both in the gas phase and when solvated in water, and compared with spectra simulated using a combination of classical molecular dynamics and first principles density functional theory in the excited state core hole approximation. The excellent agreement enabled detailed assignments. Pyrrole is highly reactive, particularly in water, and reaction products formed by the auto-oligomerization of pyrrole are identified. The solvated spectra have been measured at two different temperatures, indicating that the final states remain largely unaffected by both hydration and temperature. This is somewhat unexpected, since the nitrogen in pyrrole can donate a hydrogen bond to water.

Advanced Light Source; Schwartz, Craig P.; Uejio, Janel S.; Duffin, Andrew M.; England, Alice H.; Prendergast, David; Saykally, Richard J

2009-05-29T23:59:59.000Z

327

Steady-State and Dynamic Modeling of Gas-Phase Polypropylene Processes Using Stirred-Bed Reactors  

E-Print Network [OSTI]

Steady-State and Dynamic Modeling of Gas-Phase Polypropylene Processes Using Stirred-Bed Reactors for the continuous gas-phase synthesis of polypropylene using stirred-bed reactors. The model considers the important- terization, and reactor residence time, in addition to the traditional Ziegler-Natta polymerization kinetics

Liu, Y. A.

328

Dynamical System Analysis of Modified Chaplygin Gas in Einstein-Aether Gravity  

E-Print Network [OSTI]

In this work we investigate the background dynamics when dark energy is coupled to dark matter with a suitable interaction in the universe described by Einstein-Aether gravity. Dark energy in the form of Modified Chaplygin gas is considered. A suitable interaction between dark energy and dark matter is considered in order to at least alleviate (if not solve) the cosmic coincidence problem. The dynamical system of equations is solved numerically and a stable scaling solution is obtained. A significant attempt towards the solution of the cosmic coincidence problem is taken. The statefinder parameters are also calculated to classify the dark energy models. Graphs and phase diagrams are drawn to study the variations of these parameters. It is also seen that the background dynamics of modified Chaplygin gas in Einstein-Aether gravity is completely consistent with the notion of an accelerated expansion in the late universe. Finally, it has been shown that the universe follows the power law form of expansion around the critical point.

Chayan Ranjit; Prabir Rudra; Sujata Kundu

2014-08-19T23:59:59.000Z

329

Distributed delay model for density wave dynamics in gas lifted wells Laure Sin`egre, Nicolas Petit  

E-Print Network [OSTI]

Distributed delay model for density wave dynamics in gas lifted wells Laure Sin`egre, Nicolas Petit in the tubing D. dynamical choking is used to stabilise the density wave instability. In this paper, we propose instabilities cause production losses. One of these instabilities, referred to as the "density-wave

330

Clathrate hydrates as a sink of noble gases in Titan's atmosphere  

E-Print Network [OSTI]

We use a statistical thermodynamic approach to determine the composition of clathrate hydrates which may form from a multiple compound gas whose composition is similar to that of Titan's atmosphere. Assuming that noble gases are initially present in this gas phase, we calculate the ratios of xenon, krypton and argon to species trapped in clathrate hydrates. We find that these ratios calculated for xenon and krypton are several orders of magnitude higher than in the coexisting gas at temperature and pressure conditions close to those of Titan's present atmosphere at ground level. Furthermore we show that, by contrast, argon is poorly trapped in these ices. This trapping mechanism implies that the gas-phase is progressively depleted in xenon and krypton when the coexisting clathrate hydrates form whereas the initial abundance of argon remains almost constant. Our results are thus compatible with the deficiency of Titan's atmosphere in xenon and krypton measured by the {\\it Huygens} probe during its descent on J...

Thomas, C; Ballenegger, V; Picaud, Sylvain

2007-01-01T23:59:59.000Z

331

Quasiparticle spectrum and dynamical stability of an atomic Bose-Einstein condensate coupled to a degenerate Fermi gas  

E-Print Network [OSTI]

The quasiparticle excitations and dynamical stability of an atomic Bose-Einstein condensate coupled to a quantum degenerate Fermi gas of atoms at zero temperature is studied. The Fermi gas is assumed to be either in the normal state or to have undergone a phase transition to a superfluid state by forming Cooper pairs. The quasiparticle excitations of the Bose-Einstein condensate exhibit a dynamical instability due to a resonant exchange of energy and momentum with quasiparticle excitations of the Fermi gas. The stability regime for the bosons depends on whether the Fermi gas is in the normal state or in the superfluid state. We show that the energy gap in the quasiparticle spectrum for the superfluid state stabilizes the low energy energy excitations of the condensate. In the stable regime, we calculate the boson quasiparticle spectrum, which is modified by the fluctuations in the density of the Fermi gas.

C. P. Search; H. Pu; W. Zhang; P. Meystre

2001-12-20T23:59:59.000Z

332

Critical Dynamics of Spontaneous Symmetry Breaking in a Homogeneous Bose gas  

E-Print Network [OSTI]

We explore the dynamics of spontaneous symmetry breaking in a homogeneous system by thermally quenching an atomic gas with short-range interactions through the Bose-Einstein phase transition. Using homodyne matter-wave interferometry to measure first-order correlation functions, we verify the central quantitative prediction of the Kibble-Zurek theory, namely the homogeneous-system power-law scaling of the coherence length with the quench rate. Moreover, we directly confirm its underlying hypothesis, the freezing of the correlation length near the transition due to critical slowing down. Our measurements agree with beyond mean-field theory, and support the previously unverified expectation that the dynamical critical exponent for this universality class, which includes the $\\lambda$-transition of liquid $^4$He, is $z=3/2$.

Nir Navon; Alexander L. Gaunt; Robert P. Smith; Zoran Hadzibabic

2014-10-30T23:59:59.000Z

333

Natural Gas Utilities Options Analysis for the Hydrogen  

E-Print Network [OSTI]

Natural Gas Gas Hydrates Kent Perry Executive Director Exploration & Production Technology Distributed Hydrogen Fuel Processing Low-Temperature Fuel Cells High-Temperature Fuel Cells Vehicle Fuel Infrastructure Gerry Runte Executive Director Hydrogen Energy Systems Gasification & Hot Gas Cleanup Process

334

Methane Hydrates: Major Energy Source for the Future or Wishful Thinking?  

SciTech Connect (OSTI)

Methane hydrates are methane bearing, ice-like materials that occur in abundance in permafrost areas such as on the North Slope of Alaska and Canada and as well as in offshore continental margin environments throughout the world including the Gulf of Mexico and the East and West Coasts of the United States. Methane hydrate accumulations in the United States are currently estimated to be about 200,000 Tcf, which is enormous when compared to the conventional recoverable resource estimate of 2300 Tcf. On a worldwide basis, the estimate is 700,000 Tcf or about two times the total carbon in coal, oil and conventional gas in the world. The enormous size of this resource, if producible to any degree, has significant implications for U.S. and worldwide clean energy supplies and global environmental issues. Historically the petroleum industry's interests in methane hydrates have primarily been related to safety issues such as wellbore stability while drilling, seafloor stability, platform subsidence, and pipeline plugging. Many questions remain to be answered to determine if any of this potential energy resource is technically and economically viable to produce. Major technical hurdles include: 1) methods to find, characterize, and evaluate the resource; 2) technology to safely and economically produce natural gas from methane hydrate deposits; and 3) safety and seafloor stability issues related to drilling through gas hydrate accumulations to produce conventional oil and gas. The petroleum engineering profession currently deals with gas hydrates in drilling and production operations and will be key to solving the technical and economic problems that must be overcome for methane hydrates to be part of the future energy mix in the world.

Thomas, Charles Phillip

2001-09-01T23:59:59.000Z

335

Experimental Investigation of Propped Fracture Conductivity in Tight Gas Reservoirs Using The Dynamic Conductivity Test  

E-Print Network [OSTI]

in unconventional reservoirs such as coalbed methane, shale gas and tight gas reservoirs. Developing these types of unconventional gas reservoirs improves our energy security, and benefits the overall economy. Also, natural gas is one of the cleanest and most...

Romero Lugo, Jose 1985-

2012-10-24T23:59:59.000Z

336

Gas Hydrate: A Realistic Future Source of Gas Supply?  

Broader source: Energy.gov [DOE]

A Department of Energy scientist writes in this week's Science magazine that a search is underway for a potentially immense untapped energy resource that, given its global distribution, has the potential to alter existing energy production and supply paradigms.

337

Additives and method for controlling clathrate hydrates in fluid systems  

DOE Patents [OSTI]

Discussed is a process for preventing clathrate hydrate masses from detrimentally impeding the possible flow of a fluid susceptible to clathrate hydrate formation. The process is particularly useful in the natural gas and petroleum production, transportation and processing industry where gas hydrate formation can cause serious problems. Additives preferably contain one or more five member, six member and/or seven member cyclic chemical groupings. Additives include polymers having lactam rings. Additives can also contain polyelectrolytes that are believed to improve conformance of polymer additives through steric hindrance and/or charge repulsion. Also, polymers having an amide on which a C{sub 1}-C{sub 4} group is attached to the nitrogen and/or the carbonyl carbon of the amide may be used alone, or in combination with ring-containing polymers for enhanced effectiveness. Polymers having at least some repeating units representative of polymerizing at least one of an oxazoline, an N-substituted acrylamide and an N-vinyl alkyl amide are preferred.

Sloan, E.D. Jr.; Christiansen, R.L.; Lederhos, J.P.; Long, J.P.; Panchalingam, V.; Du, Y.; Sum, A.K.W.

1997-06-17T23:59:59.000Z

338

Additives and method for controlling clathrate hydrates in fluid systems  

DOE Patents [OSTI]

Discussed is a process for preventing clathrate hydrate masses from detrimentally impeding the possible flow of a fluid susceptible to clathrate hydrate formation. The process is particularly useful in the natural gas and petroleum production, transportation and processing industry where gas hydrate formation can cause serious problems. Additives preferably contain one or more five member, six member and/or seven member cyclic chemical groupings. Additives include polymers having lactam rings. Additives can also contain polyelectrolytes that are believed to improve conformance of polymer additives through steric hinderance and/or charge repulsion. Also, polymers having an amide on which a C.sub.1 -C.sub.4 group is attached to the nitrogen and/or the carbonyl carbon of the amide may be used alone, or in combination with ring-containing polymers for enhanced effectiveness. Polymers having at least some repeating units representative of polymerizing at least one of an oxazoline, an N-substituted acrylamide and an N-vinyl alkyl amide are preferred.

Sloan, Jr., Earle Dendy (Golden, CO); Christiansen, Richard Lee (Littleton, CO); Lederhos, Joseph P. (Wheatridge, CO); Long, Jin Ping (Dallas, TX); Panchalingam, Vaithilingam (Lakewood, CO); Du, Yahe (Golden, CO); Sum, Amadeu Kun Wan (Golden, CO)

1997-01-01T23:59:59.000Z

339

Thermal analysis of adsorptive natural gas storages during dynamic charge phase at room temperature  

SciTech Connect (OSTI)

The thermal behavior of an adsorptive natural gas (ANG) vessel pressurized continuously with light hydrocarbon gases and their mixture at 27 C was analyzed using two different activated carbons. Activated carbon AC-L showed better isothermal storage capacity than AC-D due to its sufficient porous structure. However, higher adsorption capacity claimed more extreme thermal fluctuation represented by a temperature rise of 99.2 C at the center region of the bed charged continuously with methane at 1 L min{sup -1} up to pressure of 4 MPa, corresponding to 82.5 C in AC-D bed. Higher charge rate of 5 L min{sup -1} claimed severer thermal fluctuation of 116 C in AC-L/methane system calling for a serious reduction of 26.9% in the dynamic storage capacity with respect to the isothermal storage capacity. This reduction brought the storage system to a working pressure of about 2.5 MPa rather than the desired working pressure of {proportional_to}4 MPa (about 40% reduction in storage pressure). The severest temperature rise was at the center region caused by bed poor thermal conductivity leading to limited heat transfer. High ethane and propane portions in natural gas may contribute to the thermal fluctuation of the storage system as their heats of adsorption are higher than that for methane. (author)

Ridha, Firas N.; Yunus, Rosli M.; Rashid, Mohd. [Department of Chemical Engineering, University of Technology Malaysia, 81310 UTM, Skudai, Johor (Malaysia); Ismail, Ahmad F. [Department of Gas Engineering, University of Technology Malaysia, 81310 UTM, Skudai, Johor (Malaysia)

2007-10-15T23:59:59.000Z

340

Dynamic instabilities in spark-ignited combustion engines with high exhaust gas recirculation  

SciTech Connect (OSTI)

We propose a cycle-resolved dynamic model for combustion instabilities in spark-ignition engines operating with high levels of exhaust gas recirculation (EGR). High EGR is important for increasing fuel efficiency and implementing advanced low-emission combustion modes such as homogenous charge compression ignition (HCCI). We account for the complex combustion response to cycle-to-cycle feedback by utilizing a global probability distribution that describes the pre-spark state of in-cylinder fuel mixing. The proposed model does a good job of simulating combustion instabilities observed in both lean-fueling engine experiments and in experiments where nitrogen dilution is used to simulate some of the combustion inhibition of EGR. When used to simulate high internal EGR operation, the model exhibits a range of global bifurcations and chaos that appear to be very robust. We use the model to show that it should be possible to reduce high EGR combustion instabilities by switching from internal to external EGR. We also explain why it might be helpful to deliberately stratify the fuel in the pre-spark gas mixture. It might be possible to extend the simple approach used in this model to other chemical reaction systems with spatial inhomogeneity.

Daw, C Stuart [ORNL] [ORNL; FINNEY, Charles E A [ORNL] [ORNL

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Modelling of the dynamics of a low-speed gas-liquid heat engine  

SciTech Connect (OSTI)

This paper deals with the simulation model of a gas-liquid heat engine which is characterized by very low speeds (1-3 rpm) and relatively high torque. The engine operates according to the Minto Thermal Wheel' principle. It is based on the conversion of thermal energy from the heat source, through gas expansion, into mechanical work, by means of the fall of a mass of liquid. A prototype has already been constructed showing great ability to operate at very low temperature differences between the heat source and heat sink. This makes the engine quite suitable to the utilization of low temperature heat sources such as solar energy and waste heat. On the other hand, the number of moving parts is kept to a minimum, since the piston of traditional positive displacement engines (PDE) is now replaced simply by a mass of liquid. The mathematical model consists of applying the energy equation, in it time-derivative form, to representative engine control volumes, resulting in a set of linear ordinary differential equations. Their integration provides the time variation of pressure and temperature of the working fluid. The engine performance can thus be predicted as a function of engine operating conditions and geometric characteristics. In this paper, the engine dynamics (i.e., variable angular speed) have been taken into account, as well as heat losses in the engine structure. Results and further design considerations are discussed.

Cunha, C.M.P.; Parise, J.A.R. (Pontificia Univ. Catolica do Rio de Janeiro (Brazil))

1992-01-01T23:59:59.000Z

342

A dynamical model of supernova feedback: gas outflows from the interstellar medium  

E-Print Network [OSTI]

We present a dynamical model of supernova feedback which follows the evolution of pressurised bubbles driven by supernovae in a multi-phase interstellar medium (ISM). The bubbles are followed until the point of break-out into the halo, starting from an initial adiabatic phase to a radiative phase. We show that a key property which sets the fate of bubbles in the ISM is the gas surface density, through the work done by the expansion of bubbles and its role in setting the gas scaleheight. The multi-phase description of the ISM is essential, and neglecting it leads to order of magnitude differences in the predicted outflow rates. We compare our predicted mass loading and outflow velocities to observations of local and high-redshift galaxies and find good agreement. With the aim of analysing the dependence of the mass loading of the outflow, $\\beta$ (i.e. the ratio between the outflow and star formation rates), on galaxy properties, we embed our model in the galaxy formation simulation, GALFORM, set in the $\\Lamb...

Lagos, Claudia; Baugh, C M

2013-01-01T23:59:59.000Z

343

Gas giant planets as dynamical barriers to inward-migrating super-Earths  

E-Print Network [OSTI]

Planets of 1-4 times Earth's size on orbits shorter than 100 days exist around 30-50% of all Sun-like stars. In fact, the Solar System is particularly outstanding in its lack of "hot super-Earths" (or "mini-Neptunes"). These planets -- or their building blocks -- may have formed on wider orbits and migrated inward due to interactions with the gaseous protoplanetary disk. Here, we use a suite of dynamical simulations to show that gas giant planets act as barriers to the inward migration of super-Earths initially placed on more distant orbits. Jupiter's early formation may have prevented Uranus and Neptune (and perhaps Saturn's core) from becoming hot super-Earths. Our model predicts that the populations of hot super-Earth systems and Jupiter-like planets should be anti-correlated: gas giants (especially if they form early) should be rare in systems with many hot super-Earths. Testing this prediction will constitute a crucial assessment of the validity of the migration hypothesis for the origin of close-in supe...

Izidoro, Andre; Morbidelli, Alessandro; Hersant, Franck; Pierens, Arnaud

2015-01-01T23:59:59.000Z

344

Geomechanical Performance of Hydrate-Bearing Sediments in Offshore Environments  

SciTech Connect (OSTI)

The main objective of this study is to develop the necessary knowledge base and quantitative predictive capability for the description of geomechanical performance of hydrate bearing sediments (hereafter referred to as HBS) in oceanic environments. The focus is on the determination of the envelope of hydrate stability under conditions typical of those related to the construction and operation of offshore platforms. To achieve this objective, we have developed a robust numerical simulator of hydrate behavior in geologic media by coupling a reservoir model with a commercial geomechanical code. To be sure our geomechanical modeling is realistic, we are also investigating the geomechanical behavior of oceanic HBS using pore-scale models (conceptual and mathematical) of fluid flow, stress analysis, and damage propagation. In Phase II of the project, we will review all published core data and generate additional core data to verify the models. To generate data for our models, we are using data from the literature and we will be conducting laboratory studies in 2007 that generate data to (1) evaluate the conceptual pore-scale models, (2) calibrate the mathematical models, (3) determine dominant relations and critical parameters defining the geomechanical behavior of HBS, and (4) establish relationships between the geomechanical status of HBS and the corresponding geophysical signature. The milestones for Phase I of this project are given as follows: Literature survey on typical sediments containing gas hydrates in the ocean (TAMU); Recommendations on how to create typical sediments in the laboratory (TAMU); Demonstrate that typical sediments can be created in a repeatable manner in the laboratory and gas hydrates can be created in the pore space (TAMU); Develop a conceptual pore-scale model based on available data and reports (UCB); Test the developed pore-scale concepts on simple configurations and verify the results against known measurements and observations (UCB); Complete the FLAC3D routines that will be linked with the reservoir model (LBNL); Complete the TOUGH+/HYDRATE modifications and extensions (LBNL); Complete the TOUGH+/FLAC3D interaction interface (LBNL); Integrate and test the coupled geomechanical numerical model TFxH/FLAC3D (LBNL); and Demonstrate that Petrel can be used to develop an earth model for providing data to the TOUGH+/FLAC3D (SLB).

Stephen A. Holditch

2006-12-31T23:59:59.000Z

345

Metal halogen battery construction with improved technique for producing halogen hydrate  

DOE Patents [OSTI]

An improved electrical energy storage system comprising, at least one cell having a positive electrode and a negative electrode separated by aqueous electrolyte, a store means wherein halogen hydrate is formed and stored as part of an aqueous material having a liquid level near the upper part of the store, means for circulating electrolyte through the cell, conduit means for transmitting halogen gas formed in the cell to a hydrate forming apparatus associated with the store, said hydrate forming apparatus including, a pump to which there is introduced quantities of the halogen gas and chilled water, said pump being located in the store and an outlet conduit leading from the pump and being substantially straight and generally vertically disposed and having an exit discharge into the gas space above the liquid level in the store, and wherein said hydrate forming apparatus is highly efficient and very resistant to plugging or jamming. The disclosure also relates to an improved method for producing chlorine hydrate in zinc chlorine batteries.

Fong, Walter L. (Royal Oak, MI); Catherino, Henry A. (Rochester, MI); Kotch, Richard J. (Mt. Clemens, MI)

1983-01-01T23:59:59.000Z

346

A dynamic process model of a natural gas combined cycle -- Model development with startup and shutdown simulations  

SciTech Connect (OSTI)

Research in dynamic process simulation for integrated gasification combined cycles (IGCC) with carbon capture has been ongoing at the National Energy Technology Laboratory (NETL), culminating in a full operator training simulator (OTS) and immersive training simulator (ITS) for use in both operator training and research. A derivative work of the IGCC dynamic simulator has been a modification of the combined cycle section to more closely represent a typical natural gas fired combined cycle (NGCC). This paper describes the NGCC dynamic process model and highlights some of the simulator’s current capabilities through a particular startup and shutdown scenario.

Liese, Eric [U.S. DOE; Zitney, Stephen E. [U.S. DOE

2013-01-01T23:59:59.000Z

347

Polymer electrolyte membranes from fluorinated polyisoprene-block-sulfonated polystyrene: Structural evolution with hydration and heating  

SciTech Connect (OSTI)

Small-angle neutron scattering (SANS) and ultra-small-angle X-ray scattering (USAXS) have been used to study the structural changes in fluorinated polyisoprene/sulfonated polystyrene (FISS) diblock copolymers as they evolved from the dry state to the water swollen state. A dilation of the nanometer-scale hydrophilic domains has been observed as hydration increased, with greater dilation occurring in the more highly sulfonated samples or upon hydration at higher temperatures. Furthermore, a decrease in the order in these phase separated structures is observed upon swelling. The glass transition temperatures of the fluorinated blocks have been observed to decrease upon hydration of these materials, and at the highest hydration levels, differential scanning calorimetry (DSC) has shown the presence of tightly bound water. A precipitous drop in the mechanical integrity of the 50% sulfonated materials is also observed upon exceeding the glass transition temperature (Tg), as measured by dynamic mechanical analysis (DMA).

Sodeye, Akinbode [Department of Polymer Science and Engineering, University of Massachusetts; Huang, Tianzi [University of Tennessee, Knoxville (UTK); Gido, Samuel [University of Massachusetts, Amherst; Mays, Jimmy [ORNL

2011-01-01T23:59:59.000Z

348

Imaging Hydrated Microbial Extracellular Polymers: Comparative...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

dehydration-based sample preparation that resulted in the collapse of hydrated gel-like EPS into filamentous structures. Dehydration-induced polymer collapse can lead to...

349

A Mathematical Model for Predicting the Life of PEM Fuel Cell Membranes Subjected to Hydration Cycling  

E-Print Network [OSTI]

Under typical PEM fuel cell operating conditions, part of membrane electrode assembly is subjected to humidity cycling due to variation of inlet gas RH and/or flow rate. Cyclic membrane hydration/dehydration would cause cyclic swelling/shrinking of the unconstrained membrane. In a constrained membrane, it causes cyclic stress resulting in mechanical failure in the area adjacent to the gas inlet. A mathematical modeling framework for prediction of the lifetime of a PEM FC membrane subjected to hydration cycling is developed in this paper. The model predicts membrane lifetime as a function of RH cycling amplitude and membrane mechanical properties. The modeling framework consists of three model components: a fuel cell RH distribution model, a hydration/dehydration induced stress model that predicts stress distribution in the membrane, and a damage accrual model that predicts membrane life-time. Short descriptions of the model components along with overall framework are presented in the paper. The model was used...

Burlatsky, S F; O'Neill, J; Atrazhev, V V; Varyukhin, A N; Dmitriev, D V; Erikhman, N S

2013-01-01T23:59:59.000Z

350

IN-SITU SAMPLING AND CHARACTERIZATION OF NATURALLY OCCURRING MARINE METHANE HYDRATE USING THE D/V JOIDES RESOLUTION  

SciTech Connect (OSTI)

The primary activities accomplished during this quarter were continued efforts to develop plans for Phase 2 of this cooperative agreement based on the evolving operational planning for IODP Expedition 311, which will use the JOIDES Resolution to study marine methane hydrates along the Cascadia margin, offshore Vancouver Island. IODP Expedition 311 has been designed to further constrain the models for the formation of marine gas hydrate in subduction zone accretionary prisms. The objectives include characterizing the deep origin of the methane, its upward transport, its incorporation in gas hydrate, and its subsequent loss to the seafloor. The main attention of this expedition is on the widespread seafloor-parallel layer of dispersed gas hydrate located just above the base of the predicted stability field. In a gas hydrate formation model, methane is carried upward through regional sediment or small-scale fracture permeability, driven by the tectonic consolidation of the accretionary prism. The upward moving methane is incorporated into the gas hydrate clathrate as it enters the methane hydrate stability zone. Also important is the focusing of a portion of the upward methane flux into localized plumes or channels to form concentrations of near-seafloor gas hydrate. The amount of gas hydrate in local concentrations near the seafloor is especially important for understanding the response of marine gas hydrate to climate change. The expedition includes coring and downhole measurements at five sites across the Northern Cascadia accretionary prism. The sites will track the history of methane in an accretionary prism from (1) its production by mainly microbiological processes over a thick sediment vertical extent, (2) its upward transport through regional or locally focused fluid flow, (3) its incorporation in the regional hydrate layer above the BSR or in local concentrations at or near the seafloor, (4) methane loss from the hydrate by upward diffusion, and (5) methane oxidation and incorporation in seafloor carbonate, or expulsion to the ocean. This expedition builds on the previous Cascadia gas hydrate drilling of ODP Leg 146 and on more recent ODP Leg 204 off Oregon. Important experiments being considered for DOE/NETL funding as part of the JOI cooperative agreement include, (1) Logging-While-Drilling/Measurements-While-Drilling (LWD/MWD), (2) Pressure Core Sampling (PCS/HYACINTH) of gas hydrate, and fluid recovery under in situ conditions, (3) X-ray CT logging of whole cores under in situ conditions, and (4) Infrared thermal imaging of whole round cores to map temperature variations resulting from the presence of hydrate. Preliminary budget estimates have been made for each of these tasks and discussions are ongoing with DOE/NETL program managers to develop a final plan that can be implemented within the constraints of the available funding and logistical considerations.

Frank R. Rack; Tim Francis; Peter Schultheiss; Philip E. Long; Barry M. Freifeld

2005-04-01T23:59:59.000Z

351

Development of a dynamic simulator for a natural gas combined cycle (NGCC) power plant with post-combustion carbon capture  

SciTech Connect (OSTI)

The AVESTAR Center located at the U.S. Department of Energy’s National Energy Technology Laboratory and West Virginia University is a world-class research and training environment dedicated to using dynamic process simulation as a tool for advancing the safe, efficient and reliable operation of clean energy plants with CO{sub 2} capture. The AVESTAR Center was launched with a high-fidelity dynamic simulator for an Integrated Gasification Combined Cycle (IGCC) power plant with pre-combustion carbon capture. The IGCC dynamic simulator offers full-scope Operator Training Simulator (OTS) Human Machine Interface (HMI) graphics for realistic, real-time control room operation and is integrated with a 3D virtual Immersive Training Simulator (ITS), thus allowing joint control room and field operator training. The IGCC OTS/ITS solution combines a “gasification with CO{sub 2} capture” process simulator with a “combined cycle” power simulator into a single high-performance dynamic simulation framework. This presentation will describe progress on the development of a natural gas combined cycle (NGCC) dynamic simulator based on the syngas-fired combined cycle portion of AVESTAR’s IGCC dynamic simulator. The 574 MW gross NGCC power plant design consisting of two advanced F-class gas turbines, two heat recovery steam generators (HRSGs), and a steam turbine in a multi-shaft 2x2x1 configuration will be reviewed. Plans for integrating a post-combustion carbon capture system will also be discussed.

Liese, E.; Zitney, S.

2012-01-01T23:59:59.000Z

352

Variability of the methane trapping in martian subsurface clathrate hydrates  

E-Print Network [OSTI]

Recent observations have evidenced traces of methane CH4 heterogeneously distributed in the martian atmosphere. However, because the lifetime of CH4 in the atmosphere of Mars is estimated to be around 300-600 years on the basis of photochemistry, its release from a subsurface reservoir or an active primary source of methane have been invoked in the recent literature. Among the existing scenarios, it has been proposed that clathrate hydrates located in the near subsurface of Mars could be at the origin of the small quantities of the detected CH4. Here, we accurately determine the composition of these clathrate hydrates, as a function of temperature and gas phase composition, by using a hybrid statistical thermodynamic model based on experimental data. Compared to other recent works, our model allows us to calculate the composition of clathrate hydrates formed from a more plausible composition of the martian atmosphere by considering its main compounds, i.e. carbon dioxyde, nitrogen and argon, together with met...

Thomas, Caroline; Picaud, Sylvain; Ballenegger, Vincent

2008-01-01T23:59:59.000Z

353

Microstructural Response of Variably Hydrated Ca-Rich Montmorillonite...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Microstructural Response of Variably Hydrated Ca-Rich Montmorillonite to Supercritical CO2. Microstructural Response of Variably Hydrated Ca-Rich Montmorillonite to Supercritical...

354

ALFALFA Discovery of the Nearby Gas-rich Dwarf Galaxy Leo P. V. Neutral Gas Dynamics and Kinematics  

E-Print Network [OSTI]

We present new HI spectral line imaging of the extremely metal-poor, star-forming dwarf irregular galaxy Leo P. Our HI images probe the global neutral gas properties and the local conditions of the interstellar medium (ISM). The HI morphology is slightly elongated along the optical major-axis. We do not find obvious signatures of interaction or infalling gas at large spatial scales. The neutral gas disk shows obvious rotation, although the velocity dispersion is comparable to the rotation velocity. The rotation amplitude is estimated to be V_c = 15 +/- 5 km/s. Within the HI radius probed by these observations, the mass ratio of gas to stars is roughly 2:1, while the ratio of the total mass to the baryonic mass is ~15:1. We use this information to place Leo P on the baryonic Tully-Fisher relation, testing the baryonic content of cosmic structures in a sparsely populated portion of parameter space that has hitherto been occupied primarily by dwarf spheroidal galaxies. We detect the signature of two temperature ...

Bernstein-Cooper, Elijah Z; Elson, Edward C; Warren, Steven R; Chengalur, Jayaram; Skillman, Evan D; Adams, Elizabeth A K; Bolatto, Alberto D; Giovanelli, Riccardo; Haynes, Martha P; McQuinn, Kristen B W; Pardy, Stephen A; Rhode, Katherine L; Salzer, John J

2014-01-01T23:59:59.000Z

355

Internal hydration of protein cavities: studies on BPTIy Andrei I. Borodicha  

E-Print Network [OSTI]

to the protein is calculated from the thermodynamic cycle. The protein is viewed as a dielectric continuum March 2004 In this paper, we present a theoretical method to calculate the hydration free energies and water molecules as ligand particles. The free energy to transfer a water molecule from the gas phase

Ullmann, G. Matthias

356

Analysis of liquid natural gas as a truck fuel: a system dynamics approach  

SciTech Connect (OSTI)

The purpose of this analysis is to evaluate the potential for growth in use of liquid natural gas (LNG) fueled trucks. . A system dynamics model was constructed for the analysis and a variety of scenarios were investigated. The analysis considers the economics of LNG fuel in the context of the trucking industry to identify barriers to the increased use of LNG trucks and potential interventions or leverage points which may overcome these barriers. The study showed that today, LNG use in trucks is not yet economically viable. A large change in the savings from fuel cost or capital cost is needed for the technology to take off. Fleet owners have no way now to benefit from the environmental benefits of LNG fuel nor do they benefit from the clean burning nature of the fuel. Changes in the fuel cost differential between diesel and LNG are not a research issue. However, quantifying the improvements in reliability and wear from the use of clean fuel could support increased maintenance and warranty periods. Many people involved in the use of LNG for trucks believe that LNG has the potential to occupy a niche within the larger diesel truck business. But if LNG in trucks can become economic, the spread of fuel stations and technology improvements could lead to LNG trucks becoming the dominant technology. An assumption in our simulation work is that LNG trucks will be purchased when economically attractive. None of the simulation results show LNG becoming economic but then only to the level of a niche market.

Bray, M.A.; Sebo, D.E.; Mason, T.L.; Mills, J.I.; Rice, R.E.

1996-10-01T23:59:59.000Z

357

Experimental investigation of an innovative thermochemical process operating with a hydrate salt and moist air for thermal storage of solar  

E-Print Network [OSTI]

and moist air for thermal storage of solar energy: global performance Benoit Michela, *, Nathalie Mazeta-gas reaction, hydration, thermal storage, seasonal storage, solar energy * Corresponding author: E-mail: mazet Der energy density of the reactor, Jm -3 thermal conductivity, Wm -1 .K -1 G reactive gas

Paris-Sud XI, Université de

358

Interdependency of electricity and natural gas markets in the United States : a dynamic computational model  

E-Print Network [OSTI]

Due to high storage costs and limited storage availability, natural gas is generally used as a just-in- time resource that needs to be delivered as it is consumed. With the shale gas revolution, coal retirements and ...

Jenkins, Sandra Elizabeth

2014-01-01T23:59:59.000Z

359

Department of Energy Advance Methane Hydrates Science and Technology Projects  

Broader source: Energy.gov [DOE]

Descriptions for Energy Department Methane Hydrates Science and Technology Projects, August 31, 2012

360

Methane Hydrate Dissociation by Depressurization in a Mount Elbert Sandstone Sample: Experimental Observations and Numerical Simulations  

SciTech Connect (OSTI)

A preserved sample of hydrate-bearing sandstone from the Mount Elbert Test Well was dissociated by depressurization while monitoring the internal temperature of the sample in two locations and the density changes at high spatial resolution using x-ray CT scanning. The sample contained two distinct regions having different porosity and grain size distributions. The hydrate dissociation occurred initially throughout the sample as a result of depressing the pressure below the stability pressure. This initial stage reduced the temperature to the equilibrium point, which was maintained above the ice point. After that, dissociation occurred from the outside in as a result of heat transfer from the controlled temperature bath surrounding the pressure vessel. Numerical modeling of the test using TOUGH+HYDRATE yielded a gas production curve that closely matches the experimentally measured curve.

Kneafsey, T.; Moridis, G.J.

2011-01-15T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Experimental Investigation of Propped Fracture Conductivity in Tight Gas Reservoirs Using The Dynamic Conductivity Test.  

E-Print Network [OSTI]

??Hydraulic Fracturing stimulation technology is used to increase the amount of oil and gas produced from low permeability reservoirs. The primary objective of the process… (more)

Romero Lugo, Jose 1985-

2012-01-01T23:59:59.000Z

362

In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution  

SciTech Connect (OSTI)

The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were (1) the preliminary postcruise evaluation of the tools and measurement systems that were used during ODP Leg 204 to study hydrate deposits on Hydrate Ridge, offshore Oregon from July through September 2002; and (2) the preliminary study of the hydrate-bearing core samples preserved in pressure vessels and in liquid nitrogen cryofreezers, which are now stored at the ODP Gulf Coast Repository in College Station, TX. During ODP Leg 204, several newly modified downhole tools were deployed to better characterize the subsurface lithologies and environments hosting microbial populations and gas hydrates. A preliminary review of the use of these tools is provided herein. The DVTP, DVTP-P, APC-methane, and APC-Temperature tools (ODP memory tools) were used extensively and successfully during ODP Leg 204 aboard the D/V JOIDES Resolution. These systems provided a strong operational capability for characterizing the in situ properties of methane hydrates in subsurface environments on Hydrate Ridge during ODP Leg 204. Pressure was also measured during a trial run of the Fugro piezoprobe, which operates on similar principles as the DVTP-P. The final report describing the deployments of the Fugro Piezoprobe is provided in Appendix A of this report. A preliminary analysis and comparison between the piezoprobe and DVTP-P tools is provided in Appendix B of this report. Finally, a series of additional holes were cored at the crest of Hydrate Ridge (Site 1249) specifically geared toward the rapid recovery and preservation of hydrate samples as part of a hydrate geriatric study partially funded by the Department of Energy (DOE). In addition, the preliminary results from gamma density non-invasive imaging of the cores preserved in pressure vessels are provided in Appendix C of this report. An initial visual inspection of the samples stored in liquid nitrogen is provided in Appendix D of this report.

Frank Rack; Michael Storms; Derryl Schroeder; Brandon Dugan; Peter Schultheiss; ODP Leg 204 Shipboard Scientific Party

2002-12-31T23:59:59.000Z

363

A realistic molecular model of cement hydrates  

E-Print Network [OSTI]

Despite decades of studies of calcium-silicate-hydrate (C-S-H), the structurally complex binder phase of concrete, the interplay between chemical composition and density remains essentially unexplored. Together these ...

Ulm, Franz-Josef

364

Weakening of ice by magnesium perchlorate hydrate  

E-Print Network [OSTI]

I show that perchlorate hydrates, which have been indirectly detected at high Martian circumpolar latitudes by the Phoenix Mars Lander, have a dramatic effect upon the rheological behavior of polycrystalline water ice under ...

Lenferink, Hendrik J., 1985-

2012-01-01T23:59:59.000Z

365

Computational Fluid Dynamics Analysis of Very High Temperature Gas-Cooled Reactor Cavity Cooling System  

SciTech Connect (OSTI)

The design of passive heat removal systems is one of the main concerns for the modular very high temperature gas-cooled reactors (VHTR) vessel cavity. The reactor cavity cooling system (RCCS) is a key heat removal system during normal and off-normal conditions. The design and validation of the RCCS is necessary to demonstrate that VHTRs can survive to the postulated accidents. The computational fluid dynamics (CFD) STAR-CCM+/V3.06.006 code was used for three-dimensional system modeling and analysis of the RCCS. A CFD model was developed to analyze heat exchange in the RCCS. The model incorporates a 180-deg section resembling the VHTR RCCS experimentally reproduced in a laboratory-scale test facility at Texas A&M University. All the key features of the experimental facility were taken into account during the numerical simulations. The objective of the present work was to benchmark CFD tools against experimental data addressing the behavior of the RCCS following accident conditions. Two cooling fluids (i.e., water and air) were considered to test the capability of maintaining the RCCS concrete walls' temperature below design limits. Different temperature profiles at the reactor pressure vessel (RPV) wall obtained from the experimental facility were used as boundary conditions in the numerical analyses to simulate VHTR transient evolution during accident scenarios. Mesh convergence was achieved with an intensive parametric study of the two different cooling configurations and selected boundary conditions. To test the effect of turbulence modeling on the RCCS heat exchange, predictions using several different turbulence models and near-wall treatments were evaluated and compared. The comparison among the different turbulence models analyzed showed satisfactory agreement for the temperature distribution inside the RCCS cavity medium and at the standpipes walls. For such a complicated geometry and flow conditions, the tested turbulence models demonstrated that the realizable k-epsilon model with two-layer all y+ wall treatment performs better than the other k-epsilon and k-omega turbulence models when compared to the experimental results and the Reynolds stress transport turbulence model results. A scaling analysis was developed to address the distortions introduced by the CFD model in simulating the physical phenomena inside the RCCS system with respect to the full plant configuration. The scaling analysis demonstrated that both the experimental facility and the CFD model achieve a satisfactory resemblance of the main flow characteristics inside the RCCS cavity region, and convection and radiation heat exchange phenomena are properly scaled from the actual plant.

Angelo Frisani; Yassin A. Hassan; Victor M. Ugaz

2010-11-02T23:59:59.000Z

366

Fe-containing phases in hydrated cements  

SciTech Connect (OSTI)

In this study synchrotron X-ray absorption spectroscopy (XAS) has been applied, an element specific technique which allows Fe-containing phases to be identified in the complex mineral mixture of hydrated cements. Several Fe species contributed to the overall Fe K-edge spectra recorded on the cement samples. In the early stage of cement hydration ferrite was the dominant Fe-containing mineral. Ferrihydrite was detected during the first hours of the hydration process. After 1 day the formation of Al- and Fe-siliceous hydrogarnet was observed, while the amount of ferrihydrite decreased. The latter finding agrees with thermodynamic modeling, which predicts the formation of Fe-siliceous hydrogarnet in Portland cement systems. The presence of Al- and Fe-containing siliceous hydrogarnet was further substantiated in the residue of hydrated cement by performing a selective dissolution procedure. - Highlights: • Fe bound to ferrihydrite at early age hydration • Fe found to be stable in siliceous hydrogarnet at longer term age hydration • Fe-containing AFt and AFm phases are less stable than siliceous hydrogarnet. • The study demonstrates EXAFS used to identify amorphous or poorly crystalline phases.

Dilnesa, B.Z., E-mail: belay.dilnesa@gmail.com [Empa, Laboratory for Concrete and Construction Chemistry, Überlandstrasse 129, 8600 Dübendorf (Switzerland); Wieland, E. [Paul Scherrer Institute, Laboratory for Waste Management, 5232 Villigen PSI (Switzerland); Lothenbach, B. [Empa, Laboratory for Concrete and Construction Chemistry, Überlandstrasse 129, 8600 Dübendorf (Switzerland); Dähn, R. [Paul Scherrer Institute, Laboratory for Waste Management, 5232 Villigen PSI (Switzerland); Scrivener, K.L. [Ecole Polytechnique Federal de Lausanne (EPFL), Laboratory for Construction Materials, 1015 Lausanne (Switzerland)

2014-04-01T23:59:59.000Z

367

Quantum coherence in the dynamical excitation, ionization, and decaying of neon gas induced by X-ray laser  

E-Print Network [OSTI]

We develop a large scale quantum master equation approach to describe dynamical processes of practical open quantum systems driven by both coherent and stochastic interactions by including more than one thousand true states of the systems, motivated by the development of highly bright and fully coherent lasers in the X-ray wavelength regime. The method combines the processes of coherent dynamics induced by the X-ray laser and incoherent relaxations due to spontaneous emissions, Auger decays, and electronic collisions. As examples, theoretical investigation of {\\it real} coherent dynamics of inner-shell electrons of a neon gas, irradiated by a high-intensity X-ray laser with a full temporal coherence, is carried out with the approach. In contrast to the rate equation treatment, we find that coherence can suppress the multiphoton absorptions of a neon gas in the ultra-intense X-ray pulse, due to coherence-induced Rabi oscillations and power broadening effects. We study the influence of coherence on ionization p...

Li, Yongqiang; Dong, Wenpu; Zeng, Jiaolong; Yuan, Jianmin

2015-01-01T23:59:59.000Z

368

THE DIVERSE HOT GAS CONTENT AND DYNAMICS OF OPTICALLY SIMILAR LOW-MASS ELLIPTICAL GALAXIES  

SciTech Connect (OSTI)

The presence of hot X-ray-emitting gas is ubiquitous in massive early-type galaxies. However, much less is known about the content and physical status of the hot X-ray gas in low-mass ellipticals. In the present paper, we study the X-ray gas content of four low-mass elliptical galaxies using archival Chandra X-ray observations. The sample galaxies, NGC 821, NGC 3379, NGC 4278, and NGC 4697, have approximately identical K-band luminosities, and hence stellar masses, yet their X-ray appearance is strikingly different. We conclude that the unresolved emission in NGC 821 and NGC 3379 is built up from a multitude of faint compact objects, such as coronally active binaries and cataclysmic variables. Despite the non-detection of X-ray gas, these galaxies may host low density, and hence low luminosity, X-ray gas components, which undergo an outflow driven by a Type Ia supernova (SN Ia). We detect hot X-ray gas with a temperature of kT {approx} 0.35 keV in NGC 4278, the component of which has a steeper surface brightness distribution than the stellar light. Within the central 50'' ({approx}3.9 kpc), the estimated gas mass is {approx}3 Multiplication-Sign 10{sup 7} M{sub Sun }, implying a gas mass fraction of {approx}0.06%. We demonstrate that the X-ray gas exhibits a bipolar morphology in the northeast-southwest direction, indicating that it may be outflowing from the galaxy. The mass and energy budget of the outflow can be maintained by evolved stars and SNe Ia, respectively. The X-ray gas in NGC 4697 has an average temperature of kT {approx} 0.3 keV and a significantly broader distribution than the stellar light. The total gas mass within 90'' ({approx}5.1 kpc) is {approx}2.1 Multiplication-Sign 10{sup 8} M{sub Sun }, hence the gas mass fraction is {approx}0.4%. Based on the distribution and physical parameters of the X-ray gas, we conclude that it is most likely in hydrostatic equilibrium, although a subsonic outflow may be present.

Bogdan, Akos; David, Laurence P.; Jones, Christine; Forman, William R.; Kraft, Ralph P., E-mail: abogdan@cfa.harvard.edu [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States)

2012-10-10T23:59:59.000Z

369

Dynamics of the electric current in an ideal electron gas: a sound mode inside the quasi-particles  

E-Print Network [OSTI]

We study the equation of motion for the Noether current in an electron gas within the framework of the Schwinger-Keldysh Closed-Time-Path formalism. The equation is shown to be highly non-linear and irreversible even for a non-interacting, ideal gas of electrons at non-zero density. We truncate the linearised equation of motion, written as the Laurent series in Fourier space, so that the resulting expressions are local in time, both at zero and at small finite temperatures. Furthermore, we show that the one-loop Coulomb interactions only alter the physical picture quantitatively, while preserving the characteristics of the dynamics that the electric current exhibits in the absence of interactions. As a result of the composite nature of the Noether current, composite sound waves are found to be the dominant IR collective excitations at length scales between the inverse Fermi momentum and the mean free path that would exist in an interacting electron gas. We also discuss the difference and the transition between the hydrodynamical regime of an ideal gas, defined in this work, and the hydrodynamical regime in phenomenological hydrodynamics, which is normally used for the description of interacting gases.

Sašo Grozdanov; Janos Polonyi

2015-01-26T23:59:59.000Z

370

Gas mixing system for imaging of nanomaterials under dynamic environments by environmental transmission electron microscopy  

SciTech Connect (OSTI)

A gas mixing manifold system that is capable of delivering a stable pressure stream of a desired composition of gases into an environmental transmission electron microscope has been developed. The system is designed to provide a stable imaging environment upon changes of either the composition of the gas mixture or upon switching from one gas to another. The design of the system is described and the response of the pressure inside the microscope, the sample temperature, and sample drift in response to flow and composition changes of the system are reported.

Akatay, M. Cem [School of Materials Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States)] [School of Materials Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States); Zvinevich, Yury; Ribeiro, Fabio H., E-mail: fabio@purdue.edu, E-mail: estach@bnl.gov [Forney Hall of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Baumann, Philipp [Computer Sciences, University of Applied Sciences of Northeastern Switzerland, 4132 Muttenz, Switzerland and Department of Physics, Yeshiva University, New York, New York 10016 (United States)] [Computer Sciences, University of Applied Sciences of Northeastern Switzerland, 4132 Muttenz, Switzerland and Department of Physics, Yeshiva University, New York, New York 10016 (United States); Stach, Eric A., E-mail: fabio@purdue.edu, E-mail: estach@bnl.gov [Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973 (United States)

2014-03-15T23:59:59.000Z

371

Micro-Structured Sapphire Fiber Sensors for Simultaneous Measurements of High-T and Dynamic Gas Pressure in Harsh Environments  

SciTech Connect (OSTI)

This is the final report for the program “Micro-Structured Sapphire Fiber Sensors for Simultaneous Measurements of High Temperature and Dynamic Gas Pressure in Harsh Environments”, funded by NETL, and performed by Missouri University of Science and Technology, Clemson University and University of Cincinnati from October 1, 2009 to September 30, 2014. Securing a sustainable energy economy by developing affordable and clean energy from coal and other fossil fuels is a central element to the mission of The U.S. Department of Energy’s (DOE) National Energy Technology Laboratory (NETL). To further this mission, NETL funds research and development of novel sensor technologies that can function under the extreme operating conditions often found in advanced power systems. The main objective of this research program is to conduct fundamental and applied research that will lead to successful development and demonstration of robust, multiplexed, microstructured silica and single-crystal sapphire fiber sensors to be deployed into the hot zones of advanced power and fuel systems for simultaneous measurements of high temperature and gas pressure. The specific objectives of this research program include: 1) Design, fabrication and demonstration of multiplexed, robust silica and sapphire fiber temperature and dynamic gas pressure sensors that can survive and maintain fully operational in high-temperature harsh environments. 2) Development and demonstration of a novel method to demodulate the multiplexed interferograms for simultaneous measurements of temperature and gas pressure in harsh environments. 3) Development and demonstration of novel sapphire fiber cladding and low numerical aperture (NA) excitation techniques to assure high signal integrity and sensor robustness.

Xiao, Hai; Tsai, Hai-Lung; Dong, Junhang

2014-09-30T23:59:59.000Z

372

Investigation of Vortex Structures in Gas-Discharge Nonneutral Electron Plasma: II. Vortex Formation, Evolution and Dynamics  

E-Print Network [OSTI]

The results of experimental investigations of inhomogeneities of gas-discharge nonneutral electron plasma obtained by using the nonperturbing experimental methods [N.A. Kervalishvili, arXiv:1502.02516 [physics.plasm-ph] (2015)] have been presented. Inhomogeneities are the dense solitary vortex structures stretched along the magnetic field, the lifetime of which is much greater than the time of electron-neutral collisions. The processes of formation, evolution and dynamics of vortex structures were studied. The periodic sequence of these processes is described for different geometries of discharge device.

Kervalishvili, N A

2015-01-01T23:59:59.000Z

373

Liquefied Natural Gas (LNG) Vapor Dispersion Modeling with Computational Fluid Dynamics Codes  

E-Print Network [OSTI]

Federal regulation 49 CFR 193 and standard NFPA 59A require the use of validated consequence models to determine the vapor cloud dispersion exclusion zones for accidental liquefied natural gas (LNG) releases. For modeling purposes, the physical...

Qi, Ruifeng

2012-10-19T23:59:59.000Z

374

Clathrate hydrates as a sink of noble gases in Titan's atmosphere  

E-Print Network [OSTI]

We use a statistical thermodynamic approach to determine the composition of clathrate hydrates which may form from a multiple compound gas whose composition is similar to that of Titan's atmosphere. Assuming that noble gases are initially present in this gas phase, we calculate the ratios of xenon, krypton and argon to species trapped in clathrate hydrates. We find that these ratios calculated for xenon and krypton are several orders of magnitude higher than in the coexisting gas at temperature and pressure conditions close to those of Titan's present atmosphere at ground level. Furthermore we show that, by contrast, argon is poorly trapped in these ices. This trapping mechanism implies that the gas-phase is progressively depleted in xenon and krypton when the coexisting clathrate hydrates form whereas the initial abundance of argon remains almost constant. Our results are thus compatible with the deficiency of Titan's atmosphere in xenon and krypton measured by the {\\it Huygens} probe during its descent on January 14, 2005. However, in order to interpret the subsolar abundance of primordial Ar also revealed by {\\it Huygens}, other processes that occurred either during the formation of Titan or during its evolution must be also invoked.

C. Thomas; O. Mousis; V. Ballenegger; S. Picaud

2007-08-16T23:59:59.000Z

375

The Mission and Technology of a Gas Dynamic Trap Neutron Source for Fusion Material and Component Testing and Qualification  

SciTech Connect (OSTI)

This report summarizes discussions and conclusions of the workshop to 'Assess The Mission and Technology of a Gas Dynamic Trap Neutron Source for Fusion Material and Component Testing and Qualification'. The workshop was held at LBNL, Berkeley, CA on March 12, 2009. Most workshop attendees have worked on magnetic mirror systems, several have worked on similar neutron source designs, and others are knowledgeable of materials, fusion component, and neutral beams The workshop focused on the gas dynamic trap DT Neutron Source (DTNS) concept being developed at the Budker Institute of Nuclear Physics (BINP) in Novosibirsk, Russia. The DTNS may be described as a line source of neutrons, in contrast to a spallation or a D-Lithium source with neutrons beaming from a point, or a tokamak volume source. The DTNS is a neutral beam driven linear plasma system with magnetic mirrors to confine the energetic deuterium and tritium beam injected ions, which produce the 14 MeV neutrons. The hot ions are imbedded in warm-background plasma, which traps the neutral atoms and provides both MHD and micro stability to the plasma. The 14 MeV neutron flux ranges typically at the level of 1 to 4 MW/m2.

Molvik, A W; Simonen, T C

2009-07-17T23:59:59.000Z

376

Dynamics of the electric current in an ideal electron gas: a sound mode inside the quasi-particles  

E-Print Network [OSTI]

We study the equation of motion for the Noether current in an electron gas within the framework of the Schwinger-Keldysh Closed-Time-Path formalism. The equation is shown to be highly non-linear and irreversible even for a non-interacting, ideal gas of electrons at non-zero density. We truncate the linearised equation of motion, written as the Laurent series in Fourier space, so that the resulting expressions are local in time, both at zero and at small finite temperatures. Furthermore, we show that the one-loop Coulomb interactions only alter the physical picture quantitatively, while preserving the characteristics of the dynamics that the electric current exhibits in the absence of interactions. As a result of the composite nature of the Noether current, composite sound waves are found to be the dominant IR collective excitations at length scales between the inverse Fermi momentum and the mean free path that would exist in an interacting electron gas. We also discuss the difference and the transition betwee...

Grozdanov, Sašo

2015-01-01T23:59:59.000Z

377

Gas-Mediated Impact Dynamics in Fine-Grained Granular Materials  

E-Print Network [OSTI]

Non-cohesive granular media exhibit complex responses to sudden impact that often differ from those of ordinary solids and liquids. We investigate how this response is mediated by the presence of interstitial gas between the grains. Using high-speed x-ray radiography we track the motion of a steel sphere through the interior of a bed of fine, loose granular material. We find a crossover from nearly incompressible, fluid-like behavior at atmospheric pressure to a highly compressible, dissipative response once most of the gas is evacuated. We discuss these results in light of recent proposals for the drag force in granular media.

John R. Royer; Eric I. Corwin; Peter J. Eng; Heinrich M. Jaeger

2007-07-17T23:59:59.000Z

378

Identification of dynamic force coefficients of a labyrinth and gas damper seal using impact load excitations  

E-Print Network [OSTI]

, and the seal displacement and acceleration time responses in two orthogonal directions are measured. A frequency domain parameter identification procedure allows the determination of the seals' dynamic force coefficients over a frequency range. Tests are made...

Ransom, David Lawrence

1997-01-01T23:59:59.000Z

379

Fuel cell membrane hydration and fluid metering  

DOE Patents [OSTI]

A hydration system includes fuel cell fluid flow plate(s) and injection port(s). Each plate has flow channel(s) with respective inlet(s) for receiving respective portion(s) of a given stream of reactant fluid for a fuel cell. Each injection port injects a portion of liquid water directly into its respective flow channel. This serves to hydrate at least corresponding part(s) of a given membrane of the corresponding fuel cell(s). The hydration system may be augmented by a metering system including flow regulator(s). Each flow regulator meters an injecting at inlet(s) of each plate of respective portions of liquid into respective portion(s) of a given stream of fluid by corresponding injection port(s).

Jones, Daniel O. (Glenville, NY); Walsh, Michael M. (Fairfield, CT)

2003-01-01T23:59:59.000Z

380

Dynamics and Thermodynamics of the Low-Temperature Strongly Interacting Bose Gas  

E-Print Network [OSTI]

; 05.30.Fk; 32.80.Pj; 34.50.-s From sand piles to neuronal networks, electrons in metals and quantum the enhanced role of the interaction with respect to the ki- netic energy can drive the gas into a strongly, experiments at JILA and Rice have revived interest in these systems [6, 7]. Here we report on a quantitative

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Development of a control algorithm for a dynamic gas mixing system  

E-Print Network [OSTI]

An algorithm was developed to control the partial pressures of N2, O2, and CO2 in a gas mixing tank. The gases were premixed before being introduced into the low pressure Mars Dome. As an attempt to reduce the effects of pressure, the number...

Lovelady, April

2006-08-16T23:59:59.000Z

382

Oil and Gas Science and Technology, 2009, 64(5), 629-636, doi: 10.2516/ogst/2009042 DDDiiissscccuuussssssiiiooonnn ooofff aaagggggglllooommmeeerrraaatttiiiooonnn mmmeeeccchhhaaannniiisssmmmsss bbbeeetttwwweeeeeennn hhhyyydddrrraaattteee  

E-Print Network [OSTI]

Oil and Gas Science and Technology, 2009, 64(5), 629-636, doi: 10.2516/ogst/2009042 1. KKeeyywwoorrddss:: gas hydrate formation ; water/oil emulsions ; hydrate slurry ; agglomeration ; Population@emse.fr hal-00480033,version1-3May2010 Author manuscript, published in "Oil & Gas Science and Technology 64, 5

Paris-Sud XI, Université de

383

Liquid-state polaron theory of the hydrated electron revisited  

E-Print Network [OSTI]

The quantum path integral/classical liquid-state theory of Chandler and co-workers, created to describe an excess electron in solvent, is re-examined for the hydrated electron. The portion that models electron-water density correlations is replaced by two equations: the range optimized random phase approximation (RO-RPA), and the DRL approximation to the "two-chain" equation, both shown previously to describe accurately the static structure and thermodynamics of strongly charged polyelectrolyte solutions. The static equilibrium properties of the hydrated electron are analyzed using five different electron-water pseudopotentials. The theory is then compared with data from mixed quantum/classical Monte Carlo and molecular dynamics simulations using these same pseudopotentials. It is found that the predictions of the RO-RPA and DRL-based polaron theories are similar and improve upon previous theory, with values for almost all properties analyzed in reasonable quantitative agreement with the available simulation data. Also, it is found using the Larsen, Glover and Schwartz pseudopotential that the theories give values for the solvation free energy that are at least three times larger than that from experiment.

James P. Donley; David R. Heine; Caleb A. Tormey; David T. Wu

2014-12-25T23:59:59.000Z

384

Hydration of non-polar anti-parallel ?-sheets  

SciTech Connect (OSTI)

In this work we focus on anti-parallel ?-sheets to study hydration of side chains and polar groups of the backbone using all-atom molecular dynamics simulations. We show that: (i) water distribution around the backbone does not depend significantly on amino acid sequence, (ii) more water molecules are found around oxygen than nitrogen atoms of the backbone, and (iii) water molecules around nitrogen are highly localized in the planed formed by peptide backbones. To study hydration around side chains we note that anti-parallel ?-sheets exhibit two types of cross-strand pairing: Hydrogen-Bond (HB) and Non-Hydrogen-Bond (NHB) pairing. We show that distributions of water around alanine, leucine, and valine side chains are very different at HB compared to NHB faces. For alanine pairs, the space between side chains has a higher concentration of water if residues are located in the NHB face of the ?-sheet as opposed to the HB face. For leucine residues, the HB face is found to be dry while the space between side chains at the NHB face alternates between being occupied and non-occupied by water. Surprisingly, for valine residues the NHB face is dry, whereas the HB face is occupied by water. We postulate that these differences in water distribution are related to context dependent propensities observed for ?-sheets.

Urbic, Tomaz [Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ašker?eva 5, SI-1000 Ljubljana (Slovenia)] [Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ašker?eva 5, SI-1000 Ljubljana (Slovenia); Dias, Cristiano L., E-mail: cld@njit.edu [Physics Department, New Jersey Institute of Technology, Newark, New Jersey 07102-1982 (United States)

2014-04-28T23:59:59.000Z

385

Dehydration of plutonium or neptunium trichloride hydrate  

DOE Patents [OSTI]

A process is described for preparing anhydrous actinide metal trichlorides of plutonium or neptunium by reacting an aqueous solution of an actinide metal trichloride selected from the group consisting of plutonium trichloride or neptunium trichloride with a reducing agent capable of converting the actinide metal from an oxidation state of +4 to +3 in a resultant solution, evaporating essentially all the solvent from the resultant solution to yield an actinide trichloride hydrate material, dehydrating the actinide trichloride hydrate material by heating the material in admixture with excess thionyl chloride, and recovering anhydrous actinide trichloride.

Foropoulos, J. Jr.; Avens, L.R.; Trujillo, E.A.

1992-03-24T23:59:59.000Z

386

A study of the effects of inlet preswirl on the dynamic coefficients of a straight-bore honeycomb gas damper seal  

E-Print Network [OSTI]

A STUDY OF THE EFFECTS OF INLET PRESWIRL ON THE DYNAMIC COEFFICIENTS OF A STRAIGHT-BORE HONEYCOMB GAS DAMPER SEAL A Thesis by TONY BRANDON SPROWL Submitted to the Office of Graduate Studies of Texas A&M University...-BORE HONEYCOMB GAS DAMPER SEAL A Thesis by TONY BRANDON SPROWL Submitted to Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved as to style and content by...

Sprowl, Tony Brandon

2005-02-17T23:59:59.000Z

387

Chemical dynamics in the gas phase: Time-dependent quantum mechanics of chemical reactions  

SciTech Connect (OSTI)

A major goal of this research is to obtain an understanding of the molecular reaction dynamics of three and four atom chemical reactions using numerically accurate quantum dynamics. This work involves: (i) the development and/or improvement of accurate quantum mechanical methods for the calculation and analysis of the properties of chemical reactions (e.g., rate constants and product distributions), and (ii) the determination of accurate dynamical results for selected chemical systems, which allow one to compare directly with experiment, determine the reliability of the underlying potential energy surfaces, and test the validity of approximate theories. This research emphasizes the use of recently developed time-dependent quantum mechanical methods, i.e. wave packet methods.

Gray, S.K. [Argonne National Laboratory, IL (United States)

1993-12-01T23:59:59.000Z

388

Barnett Shale Municipal Oil and Gas Ordinance Dynamics: A Spatial Perspective  

E-Print Network [OSTI]

criticisms of shale gas wells is the environmental impact, not the least of which is watershed and aquifer degradation due to the usage of fracking fluids (Mantell 2011) that contain known carcinogens including benzene, toluene, and formaldehyde (Rahm 2011... residents concerned that drilling — or more precisely, the injection of spent fracking fluids deep underground — is jeopardizing the underlying geologic stability of the Barnett Shale (Malewitz 2014a). Municipal responses to impacts In an effort to allay...

Murphy, Trey Daniel-Aaron

2013-09-27T23:59:59.000Z

389

Gas Phase Reaction with FT-ICR and Molecular Dynamics Simulation of Precursor Clusters for SWNTs  

E-Print Network [OSTI]

of the random cage delayed the annealing of the cage. Number of Carbon Atoms Intensity(arbitrary) NiC38 ­ CoC38 dynamics simulations of metal-containing carbon cluster formation were performed. Metal-carbon binary clusters were generated by the laser vaporization of Ni/Co or Ni/Y loaded carbon materials used

Maruyama, Shigeo

390

The Development of Dynamic Operational Risk Assessment in Oil/Gas and Chemical Industries  

E-Print Network [OSTI]

of reliability and safety, conventional approaches that are static reveal their weakness in nature when applied to dynamic processes[7, 8]. For instance, fault tree/event tree analysis (FTA/ETA)[9], initially applied in nuclear power plants, collects a set...

Yang, Xiaole

2011-08-08T23:59:59.000Z

391

Investigation of Gas Solid Fluidized Bed Dynamics with Non-Spherical Particles  

SciTech Connect (OSTI)

One of the largest challenges for 21st century is to fulfill global energy demand while also reducing detrimental impacts of energy generation and use on the environment. Gasification is a promising technology to meet the requirement of reduced emissions without compromising performance. Coal gasification is not an incinerating process; rather than burning coal completely a partial combustion takes place in the presence of steam and limited amounts of oxygen. In this controlled environment, a chemical reaction takes place to produce a mixture of clean synthetic gas. Gas-solid fluidized bed is one such type of gasification technology. During gasification, the mixing behavior of solid (coal) and gas and their flow patterns can be very complicated to understand. Many attempts have taken place in laboratory scale to understand bed hydrodynamics with spherical particles though in actual applications with coal, the particles are non-spherical. This issue drove the documented attempt presented here to investigate fluidized bed behavior using different ranges of non-spherical particles, as well as spherical. For this investigation, various parameters are controlled that included particle size, bed height, bed diameter and particle shape. Particles ranged from 355 µm to 1180 µm, bed diameter varied from 2 cm to 7 cm, two fluidized beds with diameters of 3.4 cm and 12.4 cm, for the spherical and non-spherical shaped particles that were taken into consideration. Pressure drop was measured with increasing superficial gas velocity. The velocity required in order to start to fluidize the particle is called the minimum fluidization velocity, which is one of the most important parameters to design and optimize within a gas-solid fluidized bed. This minimum fluidization velocity was monitored during investigation while observing variables factors and their effect on this velocity. From our investigation, it has been found that minimum fluidization velocity is independent of bed height for both spherical and non-spherical particles. Further, it decrease with decreasing particle size and decreases with decreasing bed diameter. Shadow sizing, a non-intrusive imaging and diagnostic technology, was also used to visualize flow fields inside fluidized beds for both spherical and non- spherical particles and to detect the particle sizes.

Choudhuri, Ahsan

2013-06-30T23:59:59.000Z

392

Development and initial evaluation of a dynamic species-resolved model for gas phase chemistry and size-resolved gas//particle  

E-Print Network [OSTI]

condensed products of gas phase oxidation, the present model can be viewed as the most detailed SOA of the semivolatile or nonvolatile products of VOC oxidation between the gas and particle phases. Chem- ical analysis of the SOA identifies many products that condense, thereby allowing formulation of gas phase path- ways

Dabdub, Donald

393

The effect of bubble growth dynamics on the performance of a gas evolving electrode  

E-Print Network [OSTI]

) studied the growth of electrolytic bubbles on platinum, copper, iron and nickel electrodes of di Ffer- ent diameters at various constant current levels. They used high speed photography and a series of dry cell batteries for a d. c. power source...THE EFFECT OF BUBBLE GRONTH D'rgiAMI CS ON THE PE' FOi&ilANCE OF A GAS EVOLVING ELECTRODE A Thesis By MOHAMMAD SHAMSUL HAgUE Submitted to the Graduate College of the Texas Alg& University in Partial ful fi llment of the requirements...

Haque, Mohammad Shamsul

1967-01-01T23:59:59.000Z

394

Chemically reacting plumes, gas hydrate dissociation and dendrite solidification  

E-Print Network [OSTI]

towards the ocean surface due to solar radiation. Because oftowards the ocean surface due to solar radiation and

Conroy, Devin Thomas

2008-01-01T23:59:59.000Z

395

Fuel cell design for gas hydrates exploration and research.  

E-Print Network [OSTI]

?? In this thesis the design, manufacture and testing of an Alkaline Fuel Cell (AFC) that provide electrical power to a deep sea measurement problem… (more)

Sauer, Gerhard, (Thesis)

2006-01-01T23:59:59.000Z

396

Photodetachment of Hydrated Oxalate Dianions in the Gas Phase,  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - September 2006 TheStevenAdministration Album Of

397

gas-hydrate-global-assessment | netl.doe.gov  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered energy consumption byAbout SRNL HomeYoungCleanJournalMachine ControlFuel Oil

398

Rapid Gas Hydrate Formation Process - Energy Innovation Portal  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared at 278, 298, and 323Program2Raftopoulos(MeVcm²/mg) LETEnergy

399

In silico studies of the properties of water hydrating a small protein  

SciTech Connect (OSTI)

Atomistic molecular dynamics simulation of an aqueous solution of the small protein HP-36 has been carried out with explicit solvent at room temperature. Efforts have been made to explore the influence of the protein on the relative packing and ordering of water molecules around its secondary structures, namely, three ?-helices. The calculations reveal that the inhomogeneous water ordering and density distributions around the helices are correlated with their relative hydrophobicity. Importantly, we have identified the existence of a narrow relatively dehydrated region containing randomly organized “quasi-free” water molecules beyond the first layer of “bound” waters at the protein surface. These water molecules with relatively weaker binding energies form the transition state separating the “bound” and “free” water molecules at the interface. Further, increased contribution of solid-like caging motions of water molecules around the protein is found to be responsible for reduced fluidity of the hydration layer. Interestingly, we notice that the hydration layer of helix-3 is more fluidic with relatively higher entropy as compared to the hydration layers of the other two helical segments. Such characteristics of helix-3 hydration layer correlate well with the activity of HP-36, as helix-3 contains the active site of the protein.

Sinha, Sudipta Kumar; Chakraborty, Kausik; Bandyopadhyay, Sanjoy, E-mail: sanjoy@chem.iitkgp.ernet.in [Molecular Modeling Laboratory, Department of Chemistry, Indian Institute of Technology, Kharagpur - 721302 (India); Jana, Madhurima [Molecular Simulation Laboratory, Department of Chemistry, National Institute of Technology, Rourkela - 769008 (India)

2014-12-14T23:59:59.000Z

400

Nuclear gas dynamics in Arp 220 - sub-kiloparsec scale atomic hydrogen disks  

E-Print Network [OSTI]

We present new, high angular resolution (~0.22") MERLIN observations of neutral hydrogen (HI) absorption and 21-cm radio continuum emission across the central ~900 parsecs of the ultraluminous infrared galaxy, Arp220. Spatially resolved HI absorption is detected against the morphologically complex and extended 21-cm radio continuum emission, consistent with two counterrotating disks of neutral hydrogen, with a small bridge of gas connecting the two. We propose a merger model in which the two nuclei represent the galaxy cores which have survived the initial encounter and are now in the final stages of merging, similar to conclusions drawn from previous CO studies (Sakamoto, Scoville & Yun 1999). However, we suggest that instead of being coplanar with the main CO disk (in which the eastern nucleus is embedded), the western nucleus lies above it and, as suggested by bridge of HI connecting the two nuclei, will soon complete its final merger with the main disk. We suggest that the collection of radio supernovae (RSN) detected in VLBA studies in the more compact western nucleus represent the second burst of star formation associated with this final merger stage and that free-free absorption due to ionised gas in the bulge-like component can account for the observed RSN distribution. (Abridged)

C. G. Mundell; P Ferruit; A Pedlar

2001-06-13T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Non-equilibrium dynamics of an ultracold Bose gas under a multi-pulsed quantum quench in interaction  

E-Print Network [OSTI]

We investigate the nonequilibrium dynamical properties of a weakly-interacting Bose gas at zero temperature under the multi-pulsed quantum quench in interaction by calculating one-body, two-body correlation functions and Tan's contact of the model system. The multi-pulsed quench is represented as follows: first suddenly quenching the interatomic interaction from $g_{i}$ to $g_{f}$ at time $t=0$, holding time $t$, and then suddenly quenching interaction from $g_{f}$ back to $g_{i}$, holding the time $t$ sequence $n$ times. In particular, two typical kinds of quenching parameters are chosen, corresponding to $(g_{i}/g_{f}>1)$ and $(g_{i}/g_{f}powerful way of studying the non-equilibrium dynamics of many-body quantum system than the `one-off' quantum quench. Finally, we discuss the ultra-short-range properties of the two-body correlation function after the $n$th quenching, which can be used to probe the `Tan'scontact' in experiments. All our calculations can be tested in current cold atom experiments.

Lei Chen; Zhidong Zhang; Zhaoxin Liang

2015-01-28T23:59:59.000Z

402

The Mission and Technology of a Gas Dynamic Trap Neutron Source for Fusion Material and Component Testing and Qualification  

SciTech Connect (OSTI)

The successful operation (with {beta} {le} 60%, classical ions and electrons with Te = 250 eV) of the Gas Dynamic Trap (GDT) device at the Budker Institute of Nuclear Physics (BINP) in Novosibirsk, Russia, extrapolates to a 2 MW/m{sup 2} Dynamic Trap Neutron Source (DTNS), which burns only {approx}100 g of tritium per full power year. The DTNS has no serious physics, engineering, or technology obstacles; the extension of neutral beam lines to steady state can use demonstrated engineering; and it supports near-term tokamaks and volume neutron sources. The DTNS provides a neutron spectrum similar to that of ITER and satisfies the missions specified by the materials community to test fusion materials (listed as one of the top grand challenges for engineering in the 21st century by the U.S. National Academy of Engineering) and subcomponents (including tritium-breeding blankets) needed to construct DEMO. The DTNS could serve as the first Fusion Nuclear Science Facility (FNSF), called for by ReNeW, and could provide the data necessary for licensing subsequent FSNFs.

Ivanov, A; Kulcinski, J; Molvik, A; Ryutov, D; Santarius, J; Simonen, T; Wirth, B D; Ying, A

2009-11-23T23:59:59.000Z

403

Twenty-Seventh Symposium (International) on Combustion/The Combustion Institute, 1998/pp. 22492257 SIMULATION OF THE TRANSIENT, COMPRESSIBLE, GAS-DYNAMIC  

E-Print Network [OSTI]

­2257 SIMULATION OF THE TRANSIENT, COMPRESSIBLE, GAS-DYNAMIC BEHAVIOR OF CATALYTIC-COMBUSTION IGNITION2249 Twenty-Seventh Symposium (International) on Combustion/The Combustion Institute, 1998/pp. 2249 combustion in a stagnation-flow configuration. The analysis considers the elementary heterogeneouschem- istry

Petzold, Linda R.

404

Gas Dynamics in the Barred Seyfert Galaxy NGC4151 - II. High Resolution HI Study  

E-Print Network [OSTI]

We present sensitive, high angular resolution (6" x 5") 21-cm observations of the neutral hydrogen in the nearby barred Seyfert galaxy, NGC4151. These HI observations, obtained using the VLA in B-configuration, are the highest resolution to date of this galaxy, and reveal hitherto unprecedented detail in the distribution and kinematics of the HI on sub-kiloparsec scales. A complete analysis and discussion of the HI data are presented and the global properties of the galaxy are related to the bar dynamics presented in Paper I.

C. G. Mundell; A. Pedlar; D. L. Shone; A. Robinson

1998-12-09T23:59:59.000Z

405

Characterization of the reactive flow field dynamics in a gas turbine injector using high frequency PIV  

E-Print Network [OSTI]

The present work details the analysis of the aerodynamics of an experimental swirl stabilized burner representative of gas turbine combustors. This analysis is carried out using High Frequency PIV (HFPIV) measurements in a reactive situation. While this information is usually available at a rather low rate, temporally resolved PIV measurements are necessary to better understand highly turbulent swirled flows, which are unsteady by nature. Thanks to recent technical improvements, a PIV system working at 12 kHz has been developed to study this experimental combustor flow field. Statistical quantities of the burner are first obtained and analyzed, and the measurement quality is checked, then a temporal analysis of the velocity field is carried out, indicating that large coherent structures periodically appear in the combustion chamber. The frequency of these structures is very close to the quarter wave mode of the chamber, giving a possible explanation for combustion instability coupling.

Barbosa, Séverine; Ducruix, Sébastien

2008-01-01T23:59:59.000Z

406

A Mathematical Model for Predicting the Life of PEM Fuel Cell Membranes Subjected to Hydration Cycling  

E-Print Network [OSTI]

Under typical PEM fuel cell operating conditions, part of membrane electrode assembly is subjected to humidity cycling due to variation of inlet gas RH and/or flow rate. Cyclic membrane hydration/dehydration would cause cyclic swelling/shrinking of the unconstrained membrane. In a constrained membrane, it causes cyclic stress resulting in mechanical failure in the area adjacent to the gas inlet. A mathematical modeling framework for prediction of the lifetime of a PEM FC membrane subjected to hydration cycling is developed in this paper. The model predicts membrane lifetime as a function of RH cycling amplitude and membrane mechanical properties. The modeling framework consists of three model components: a fuel cell RH distribution model, a hydration/dehydration induced stress model that predicts stress distribution in the membrane, and a damage accrual model that predicts membrane life-time. Short descriptions of the model components along with overall framework are presented in the paper. The model was used for lifetime prediction of a GORE-SELECT membrane.

S. F. Burlatsky; M. Gummalla; J. O'Neill; V. V. Atrazhev; A. N. Varyukhin; D. V. Dmitriev; N. S. Erikhman

2013-06-19T23:59:59.000Z

407

Ab initio study of the structure and dynamics of solvated highly charged metal ions  

E-Print Network [OSTI]

Study of the Structure and Dynamics of Solvated Highly27 Chapter 3 Structure and Dynamics of the High Spin Fe 3+66 Chapter 4 Structure and Dynamics of the Hydrated Ca 2+

Bogatko, Stuart A.

2008-01-01T23:59:59.000Z

408

World Gas Conference Tokyo, June 1-5, 2003  

E-Print Network [OSTI]

22nd World Gas Conference Tokyo, June 1-5, 2003 HYDRATE NON-PIPELINE TECHNOLOGY FOR TRANSPORT OF NATURAL GAS JĂłn S. Gudmundsson, Norwegian University of Science and Technology Oscar F. Graff, Aker Kvaerner Technology AS SUMMARY The economics of natural gas transport depends greatly on the annual volumes

Gudmundsson, Jon Steinar

409

Van't Hoff law for temperature dependent Langmuir constants in clathrate hydrate nanocavities  

E-Print Network [OSTI]

This work gives a van't Hoff law expression of Langmuir constants of different species for determining their occupancy in the nanocavities of clathrate hydrates. The van't Hoff law's parameters are derived from a fit with Langmuir constants calculated using a pairwise site-site interaction potential to model the anisotropic potential environment in the cavities, as a function of temperature. The parameters can be used for calculating clathrates compositions. Results are given for nineteen gas species trapped in the small and large cavities of structure types I and II [1]. The accuracy of this approach is based on a comparison with available experimental data for ethane and cyclo- propane clathrate hydrates. The numerical method applied in this work, was recently validated from a comparison with the spherical cell method based on analytical considerations [1

Lakhlifi, Azzedine

2015-01-01T23:59:59.000Z

410

Methane Hydrate Field Studies | Department of Energy  

Energy Savers [EERE]

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |EnergyonSupport0.pdf5 OPAM SEMIANNUAL REPORTMAMay 20Field Studies Methane Hydrate Field

411

Methane Hydrate Production Feasibility | Department of Energy  

Energy Savers [EERE]

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion |EnergyonSupport0.pdf5 OPAM SEMIANNUAL REPORTMAMay 20Field Studies Methane Hydrate

412

International Lige Colloquium on Ocean Dynamics, GAS TRANSFER AT WATER SURFACES, May 2 -6 2005 Estimation of air-sea gas and heat fluxes from infrared imagery and  

E-Print Network [OSTI]

2005 Estimation of air-sea gas and heat fluxes from infrared imagery and surface wave measurements and much higher heat fluxes. In addition, the infrared imagery analysis reveals potentially significant the infrared images. It is also shown that the difference in the surface boundary conditions for heat and gas

Jaehne, Bernd

413

Stability of hypersonic reacting stagnation flow of a detonatable gas mixture by dynamical systems analysis  

SciTech Connect (OSTI)

The stability characteristics of the reacting hypersonic flow of the fuel/oxidizer mixture in the stagnation region of a blunt body are studied. The conditions for oscillations of the combustion front are assumed to be determined mainly by the flow conditions at the stagnation region. The density at the stagnation region is assumed to be constant at hypersonic flow conditions. By assuming a simplified flow model, the time dependent flow equations, including the heat addition due to the chemical reactions, are reduced to a second-order nonlinear differential equation for the instantaneous temperature. The solutions are analyzed assuming a one-step chemical reaction with zero-order and first-order processes using dynamical systems methods. These methods are used to determine the stability boundaries in terms of the flow and chemical reaction parameters. It is shown that the zero-order reaction has nonperiodic solutions that may lead to explosion whereas the first-order and higher-order reactions may have periodic solutions indicating oscillations. The zero-order analysis also reaffirms the requirements for a minimum size blunt body for the establishment of a detonation (in agreement with classical detonation theory) and the first-order analysis indicates a minimum body size for establishment of oscillations. The oscillation frequencies are calculated using the small perturbation approximation for the temperature oscillations. These frequencies are compared with results from published data on spheres and hemisphere cylindrical bodies fired into hydrogen-oxygen and acetylene oxygen mixtures. Very good agreement is found between the measured and calculated results.

Tivanov, G.; Rom, J. [Technion-Israel Inst. of Tech., Haifa (Israel)] [Technion-Israel Inst. of Tech., Haifa (Israel)

1995-12-01T23:59:59.000Z

414

angiogenesis vascularity hydration: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

I. Introduction Cementpaste,the binding phaseof concrete Bentz, Dale P. 177 NISTIR 7232 CEMHYD3D: A Three-Dimensional Cement Hydration Engineering Websites Summary: NISTIR...

415

aluminum hydration effects: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

I. Introduction Cementpaste,the binding phaseof concrete Bentz, Dale P. 258 NISTIR 7232 CEMHYD3D: A Three-Dimensional Cement Hydration Engineering Websites Summary: NISTIR...

416

Energy Department Expands Research into Methane Hydrates, a Vast...  

Broader source: Energy.gov (indexed) [DOE]

separate project funded by the EU through Universities of Bremen (Germany) and Tromso (Norway), will assess the response of methane hydrates to environmental changes at the...

417

Methane Hydrate Dissociation by Depressurization in a Mount Elbert Sandstone Sample: Experimental Observations and Numerical Simulations  

E-Print Network [OSTI]

S.S.H. , 1987. Kinetics of Methane Hydrate Decomposition,T. J. , et al. (2007), Methane Hydrate Formation andCharting the future of methane hydrate research in the

Kneafsey, T.

2012-01-01T23:59:59.000Z

418

Macromolecular hydration compared with preferential hydration and their role on macromolecule-osmolyte coupled diffusionwz  

E-Print Network [OSTI]

to solute hydration and size ratio and is not complicated by other factors such as ionic interactions should not be neglected in multicomponent-diffusion theoretical models even when ionic interactions quantities that shape the thermodynamic and diffusion behavior of macromolecule­additive­water solutions.1

Annunziata, Onofrio

419

Metal-Catalyzed Hydration of 2-Pyridyloxirane  

E-Print Network [OSTI]

-401 CuSO, at 22". The rate of the copper-catalysed hydration is proportional to the copper concentration, and a t low pH the reaction obeys pseudo-first-order kinetics. At high pH the rate decreases as the reaction proceeds, probably because... the product acts as a tridentate chelating agent and removes the copper in a non-catalytic form. Thus the rate law for the reaction in O.~M-KH,PO, (pH 5.09) is: - d[epoxide]/dt= (k, + R,[Cu2+])[epoxide], where A , and Km, the rate con- stants...

Hanzlik, Robert P.; Michaely, William J.

1975-01-01T23:59:59.000Z

420

Methane Hydrate Program Annual Report to Congress  

Energy Savers [EERE]

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of Inspector General Office0-72.pdfGeorgeDoesn't32 Master EM ProjectMemoDepartmentFY 2010 Methane Hydrate

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

ESP (electrostatic precipitator) tests at Toronto: Test results: Part 3. [Hydrate Addition at Low Temperature for the removal of SO/sub 2/  

SciTech Connect (OSTI)

''Hydrate Addition at Low Temperature'' or HALT is a dry calcium-based hydrate injection process for the removal of SO/sub 2/ from flue gases off a sulfur bearing fuel. In this process the hydrate is pneumatically conveyed and injected into the flue gas stream as a dry particulate. The flue gas is cooled downstream of the hydrate injection location by spraying the gas with a stream of finely atomized water droplets. The flue gas is cooled to as low a temperature as possible by spraying water on it, maintaining an approach to saturation temperature of 20/degree/F or higher. Temperatures lower than this could cause potential problems with moisture condensation on cold duct walls, the particulate removal devices as ESP/baghouse. The waste product from this process is the dry disposable solids which differed considerably from the wet cake solids obtained from a wet FGD process. Tests performed on the electrostatic precipitator are described. The primary tasks performed were: (1) measurement of the particle size distribution, resistivity, and mass concentration of the fly ash or ash-sorbent mixture entering the ESP, (2) measurement of the collection efficiency of the ESP, (3) recording the electrical operating conditions and the voltage-current characteristics of the ESP, and (4) determination of the utilization of sorbent entering the ESP, and the additional utilization/SO/sub 2/ removal occurring within the precipitator. Chemical analyses were performed on fly ash and ash-sorbent mixtures. 30 figs., 22 tabs.

Gooch, J.; Beittel, R.; DuBard, J.; Marchant, G. Jr.

1988-12-01T23:59:59.000Z

422

Estimates of Biogenic Methane Production Rates in Deep Marine Sediments at Hydrate Ridge, Cascadia Margin  

SciTech Connect (OSTI)

Methane hydrate found in marine sediments is thought to contain gigaton quantities of methane and is considered an important potential fuel source and climate-forcing agent. Much of the methane in hydrates is biogenic, so models that predict the presence and distribution of hydrates require accurate rates of in situ methanogenesis. We estimated the in situ methanogenesis rates in Hydrate Ridge (HR) sediments by coupling experimentally derived minimal rates of methanogenesis to methanogen biomass determinations for discrete locations in the sediment column. When starved in a biomass recycle reactor Methanoculleus submarinus produced ca. 0.017 fmol methane/cell/day. Quantitative polymerase chain reaction (QPCR) directed at the methyl coenzyme M reductase subunit A (mcrA) gene indicated that 75% of the HR sediments analyzed contained <1000 methanogens/g. The highest methanogen numbers were mostly from sediments <10 meters below seafloor. By combining methanogenesis rates for starved methanogens (adjusted to account for in situ temperatures) and the numbers of methanogens at selected depths we derived an upper estimate of <4.25 fmol methane produced/g sediment/day for the samples with fewer methanogens than the QPCR method could detect. The actual rates could vary depending on the real number of methanogens and various seafloor parameters that influence microbial activity. However, our calculated rate is lower than rates previously reported from such sediments and close to the rate derived using geochemical modeling of the sediments. These data will help to improve models that predict microbial gas generation in marine sediments and determine the potential influence of this source of methane on the global carbon cycle.

F. S. Colwell; S. Boyd; M. E. Delwiche; D. W. Reed; T. J. Phelps; D. T. Newby

2008-06-01T23:59:59.000Z

423

Seismic-Scale Rock Physics of Methane Hydrate  

SciTech Connect (OSTI)

We quantify natural methane hydrate reservoirs by generating synthetic seismic traces and comparing them to real seismic data: if the synthetic matches the observed data, then the reservoir properties and conditions used in synthetic modeling might be the same as the actual, in-situ reservoir conditions. This approach is model-based: it uses rock physics equations that link the porosity and mineralogy of the host sediment, pressure, and hydrate saturation, and the resulting elastic-wave velocity and density. One result of such seismic forward modeling is a catalogue of seismic reflections of methane hydrate which can serve as a field guide to hydrate identification from real seismic data. We verify this approach using field data from known hydrate deposits.

Amos Nur

2009-01-08T23:59:59.000Z

424

Evaluation of the thermodynamic properties of hydrated metal oxide nanoparticles by INS techniques  

SciTech Connect (OSTI)

In this contribution we will present a detailed methodology for the elucidation of the following aspects of the thermodynamic properties of hydrated metal oxide nanoparticles from high-resolution, low-temperature inelastic neutron scattering (INS) data: (i) the isochoric heat capacity and entropy of the hydration layers both chemi- and physisorbed to the particle surface; (ii) the magnetic contribution to the heat capacity of the nanoparticles. This will include the calculation of the vibrational density of states (VDOS) from the raw INS spectra, and the subsequent extraction of the thermodynamic data from the VDOS. This technique will be described in terms of a worked example namely, cobalt oxide (Co3O4 and CoO). To complement this evaluation of the physical properties of metal oxide nanoparticle systems, we will emphasise the importance of high-resolution, high-energy INS for the determination of the structure and dynamics of the water species, namely molecular (H2O) and dissociated water (OH, hydroxyl), confined to the oxide surfaces. For this component of the chapter we will focus on INS investigations of hydrated isostructural rutile (a-TiO2) and cassiterite (SnO2) nanoparticles. We will complete this discussion of nanoparticle analysis by including an appraisal of the INS instrumentation employed in such studies with particular focus on TOSCA [ISIS, Rutherford Appleton Laboratory (RAL), U.K.] and the newly developed spectrometer SEQUOIA [SNS, Oak Ridge National Laboratory (ORNL), U.S.A].

Spencer, Elinor [Virginia Polytechnic Institute and State University] [Virginia Polytechnic Institute and State University; Ross, Dr. Nancy [Virginia Polytechnic Institute and State University] [Virginia Polytechnic Institute and State University; Parker, Stewart F. [ISIS Facility, Rutherford Appleton Laboratory (ISIS)] [ISIS Facility, Rutherford Appleton Laboratory (ISIS); Kolesnikov, Alexander I [ORNL] [ORNL

2013-01-01T23:59:59.000Z

425

In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution  

SciTech Connect (OSTI)

Cooperative Agreement DE-FC26-01NT41329 between Joint Oceanographic Institutions and DOE-NETL was divided into two phases based on successive proposals and negotiated statements of work pertaining to activities to sample and characterize methane hydrates on ODP Leg 204 (Phase 1) and on IODP Expedition 311 (Phase 2). The Phase 1 Final Report was submitted to DOE-NETL in April 2004. This report is the Phase 2 Final Report to DOE-NETL. The primary objectives of Phase 2 were to sample and characterize methane hydrates using the systems and capabilities of the D/V JOIDES Resolution during IODP Expedition 311, to enable scientists the opportunity to establish the mass and distribution of naturally occurring gas and gas hydrate at all relevant spatial and temporal scales, and to contribute to the DOE methane hydrate research and development effort. The goal of the work was to provide expanded measurement capabilities on the JOIDES Resolution for a dedicated hydrate cruise to the Cascadia continental margin off Vancouver Island, British Columbia, Canada (IODP Expedition 311) so that hydrate deposits in this region would be well characterized and technology development continued for hydrate research. IODP Expedition 311 shipboard activities on the JOIDES Resolution began on August 28 and were concluded on October 28, 2005. The statement of work for this project included three primary tasks: (1) research management oversight, provided by JOI; (2) mobilization, deployment and demobilization of pressure coring and core logging systems, through a subcontract with Geotek Ltd.; and, (3) mobilization, deployment and demobilization of a refrigerated container van that will be used for degassing of the Pressure Core Sampler and density logging of these pressure cores, through a subcontract with the Texas A&M Research Foundation (TAMRF). Additional small tasks that arose during the course of the research were included under these three primary tasks in consultation with the DOE-NETL Program Manager. All tasks outlined in the original statement of work were accomplished except for the deployment and use of the X-ray CT system under Subtask 2-2. This reduction in scope provided resources that were applied to other activities to support the overall project. Post-expedition analysis of results and report writing will continue beyond this reporting period, however, all field deployments associated with this project have been successfully concluded as of this writing.

Frank R. Rack

2006-09-20T23:59:59.000Z

426

Simteche Hydrate CO2 Capture Process  

SciTech Connect (OSTI)

As a result of an August 4, 2005 project review meeting held at Los Alamos National Laboratory (LANL) to assess the project's technical progress, Nexant/Simteche/LANL project team was asked to meet four targets related to the existing project efforts. The four targets were to be accomplished by the September 30, 2006. These four targets were: (1) The CO{sub 2} hydrate process needs to show, through engineering and sensitivity analysis, that it can achieve 90% CO{sub 2} capture from the treated syngas stream, operating at 1000 psia. The cost should indicate the potential of achieving the Sequestration Program's cost target of less than 10% increase in the cost of electricity (COE) of the non-CO{sub 2} removal IGCC plant or demonstrate a significant cost reduction from the Selexol process cost developed in the Phase II engineering analysis. (2) The ability to meet the 20% cost share requirement for research level efforts. (3) LANL identifies through equilibrium and bench scale testing a once-through 90% CO{sub 2} capture promoter that supports the potential to achieve the Sequestration Program's cost target. Nexant is to perform an engineering analysis case to verify any economic benefits, as needed; no ETM validation is required, however, for this promoter for FY06. (4) The CO{sub 2} hydrate once-through process is to be validated at 1000 psia with the ETM at a CO{sub 2} capture rate of 60% without H{sub 2}S. The performance of 68% rate of capture is based on a batch, equilibrium data with H{sub 2}S. Validation of the test results is required through multiple runs and engineering calculations. Operational issues will be solved that will specifically effect the validation of the technology. Nexant was given the primary responsibility for Target No.1, while Simteche was mainly responsible for Target No.2; with LANL having the responsibility of Targets No.3 and No.4.

Nexant and Los Alamos National Laboratory

2006-09-30T23:59:59.000Z

427

Advanced Gas Storage Concepts: Technologies for the Future  

SciTech Connect (OSTI)

This full text product includes: 1) A final technical report titled Advanced Underground Gas Storage Concepts, Refrigerated-Mined Cavern Storage and presentations from two technology transfer workshops held in 1998 in Houston, Texas, and Pittsburgh, Pennsylvania (both on the topic of Chilled Gas Storage in Mined Caverns); 2) A final technical report titled Natural Gas Hydrates Storage Project, Final Report 1 October 1997 - 31 May 1999; 3) A final technical report titled Natural Gas Hydrates Storage Project Phase II: Conceptual Design and Economic Study, Final Report 9 June - 10 October 1999; 4) A final technical report titled Commerical Potential of Natural Gas Storage in Lined Rock Caverns (LRC) and presentations from a DOE-sponsored workshop on Alternative Gas Storage Technologies, held Feb 17, 2000 in Pittsburgh, PA; and 5) Phase I and Phase II topical reports titled Feasibility Study for Lowering the Minimum Gas Pressure in Solution-Mined Caverns Based on Geomechanical Analyses of Creep-Induced Damage and Healing.

Freeway, Katy (PB-KBB Inc.); Rogers, R.E. (Mississippi State University); DeVries, Kerry L.; Nieland, Joel D.; Ratigan, Joe L.; Mellegard, Kirby D. (RESPEC)

2000-02-01T23:59:59.000Z

428

The 'Supply-of-Storage' for Natural Gas in California  

E-Print Network [OSTI]

the Hedging Effectiveness of Natural Gas Futures. ” EnergyCommission. (2002). “Natural Gas Supply and Infrastructureand Price Dynamics in Natural Gas City Gate Markets. ”

Uria, Rocio; Williams, Jeffrey

2005-01-01T23:59:59.000Z

429

In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution  

SciTech Connect (OSTI)

The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were that: (1) Frank Rack, Anne Trehu, and Tim Collett presented preliminary results and operational outcomes of ODP Leg 204 at the American Association of Petroleum Geologists annual meeting in Salt Lake City, UT; (2) several Leg 204 scientists participated in special hydrate sessions at the international EGS/AGU/EUG meeting in Nice, France and presented initial science results from the cruise, which included outcomes arising from this cooperative agreement; and, (3) postcruise evaluation of the data, tools and measurement systems that were used during ODP Leg 204 continued in the preparation of deliverables under this agreement. At the EGS/EUG/AGU meeting in Nice, France in April, Leg 204 Co-chiefs Anne Trehu and Gerhard Bohrmann, as well as ODP scientists Charlie Paull, Erwin Suess, and Jim Kennett, participated in a press conference on hydrates. The well-attended press conference entitled ''Gas Hydrates: Free methane found and controversy over the 'hydrate gun''' led to stories in Nature on-line and BBC radio, among others. There were six (6) oral and fifteen (15) poster presentations on ODP Leg 204 hydrate science at the EGS/AGU/EUG Meeting in Nice, France on April 6-11, 2003. This was a very strong showing at a meeting just over six month following the completion of the drilling cruise and highlighted many of the results of the leg, including the results obtained with instruments and equipment funded under this cooperative agreement. At the AAPG annual meeting in Salt Lake City, UT on May 11-14, 2003, Anne Trehu gave an oral presentation about the scientific results of Leg 204, and Frank Rack presented a poster outlining the operational and technical accomplishments. Work continued on analyzing data collected during ODP Leg 204 and preparing reports on the outcomes of Phase 1 projects as well as developing plans for Phase 2.

Frank Rack; ODP Leg 204 Shipboard Scientific Party

2003-06-30T23:59:59.000Z

430

Carbon and Greenhouse Gas Dynamics in Annual Grasslands: Effects of Management and Potential for Climate Change Mitigation  

E-Print Network [OSTI]

organic wastes at different composting stages during theirbiological changes during composting of different organicand nitrogen dynamics in composting and in compost?amended

Ryals, Rebecca

2012-01-01T23:59:59.000Z

431

Carbon and Greenhouse Gas Dynamics in Annual Grasslands: Effects of Management and Potential for Climate Change Mitigation  

E-Print Network [OSTI]

dynamics and potential carbon sequestration by rangelands.G. E. Schuman. 2007. Carbon sequestration and rangelands: ASilver, W.L. in review. Carbon sequestration potential and

Ryals, Rebecca

2012-01-01T23:59:59.000Z

432

Dynamical transition from a quasi-one dimensional Bose-Einstein condensate to a Tonks-Girardeau gas  

E-Print Network [OSTI]

We analyze in detail the expansion of a 1D Bose gas after removing the axial confinement. We show that during its one-dimensional expansion the density of the Bose gas does not follow a self-similar solution, but on the contrary, it asymptotically approaches a Tonks-Girardeau profile. Our analysis is based on a nonlinear Schr\\"odinger equation with variable nonlinearity whose validity is discussed for the expansion problem, by comparing with an exact Bose-Fermi mapping for the case of an initial Tonks-Girardeau gas. For this case, the gas is shown to expand self-similarly, with a different similarity law compared to the one-dimensional Thomas-Fermi condensate.

P. Ohberg; L. Santos

2002-05-07T23:59:59.000Z

433

Carbon dioxide hydrate particles for ocean carbon sequestration  

E-Print Network [OSTI]

This paper presents strategies for producing negatively buoyant CO[subscript 2] hydrate composite particles for ocean carbon sequestration. Our study is based on recent field observations showing that a continuous-jet ...

Chow, A.C.

434

RHEOLOGICAL STUDY OF AN HYDRATE SLURRY FOR AIR CONDITIONNING APPLICATION  

E-Print Network [OSTI]

. These slurries seems to be well appropriate for cold storage and transportation in the case of air- conditioning as secondary refrigerants. Concerning hydrates, they have been used as PCM for cold storage for years

Boyer, Edmond

435

Geotechnical characterization of sediments from Hydrate Ridge, Cascadia Continental Margin  

E-Print Network [OSTI]

Eight whole core sediment samples were obtained from ODP Site 1244, Hydrate Ridge, Cascadia Continental Margin with the goal of understanding the stress history, consolidation behavior and strength characteristics of the ...

Tan, Brian B. (Brian Bautista), 1979-

2004-01-01T23:59:59.000Z

436

Dynamics of the egress of gas microbubbles from a melt under laser irradiation of a metal surface  

SciTech Connect (OSTI)

The results of a theoretical investigation of the efficiency of degassing of the near-surface region of a material exposed to laser radiation are presented. The case of a low volume concentration of the monodispersed gas phase representing microbubbles of size no greater than 10 {mu}m is considered. The principal parameters are revealed which determine the regimes of the egress of gas bubbles from a laser-produced melt, and analytical formulas are obtained for estimating the process rate. The analytical results are compared with the results of two-dimensional numerical simulations which include the laser heating of a solid sample, its melting, the development of thermocapillary melt convection, and the escape of gas bubbles from the melt. The analytical and numerical results are found to be in good agreement. (laser applications and other topics in quantum electronics)

Likhanskii, V V; Loboiko, A I [State Research Center of Russian Federation 'Troitsk Institute for Innovation and Fusion Research', Troitsk, Moscow Region (Russian Federation)

2000-09-30T23:59:59.000Z

437

Pressure-induced Hydration in Zeolite Tetranatrolite  

SciTech Connect (OSTI)

The tetranatrolite-paranatrolite transformation has remained a key problem in understanding the paragenesis of zeolites in the natrolite family. It is accepted that when paranatrolite, approximate formula Na{sub 16-x}Ca{sub x}Al{sub 16+x}Si{sub 24-x}O{sub 80}{center_dot}24H{sub 2}O, is removed from an aqueous environment and exposed to the atmosphere, it loses water and transforms to tetranatrolite, Na{sub 16-x}Ca{sub x}Al{sub 16+x}Si{sub 24-x}O{sub 80}{center_dot}nH{sub 2}O (n {le} 24). Here we show that this transformation is not only reversible, but that tetranatrolite exhibits two sequential pressure-induced hydrations leading first to paranatrolite and then to a superhydrated tetranatrolite above 0.2 and 3.0 GPa, respectively. We have previously reported similar behavior for the corresponding system with an ordered Si/Al distribution, i.e., natrolite itself, however the ordered version of paranatrolite exists over a much smaller pressure range. The pressure-induced transformations of natrolite and tetranatrolite thus further supports the supposition that paranatrolite is a distinct mineral species, with a pressure-stability field dependent upon composition.

Lee,Y.; Hriljac, J.; Parise, J.; Vogt, T.

2006-01-01T23:59:59.000Z

438

Effect of under-inhibition with methanol and ethylene glycol on the hydrate control process  

SciTech Connect (OSTI)

Hydrate control can be achieved by chemical injection. Currently, methanol and ethylene glycol are the most widely used inhibitors in offshore hydrate control operations. To achieve effective hydrate inhibition, a sufficient amount of inhibitor must be injected to shift the thermodynamic equilibrium condition for hydrate formation outside the pipeline operating pressure and temperature. Recently published field experiments showed that hydrate blockages form more readily in under-inhibited systems than in systems completely without inhibitor. A laboratory study is conducted to determine the effect of low concentration (1--5wt%) methanol and ethylene glycol on the hydrate formation process. The results show that, although these chemicals are effective hydrate inhibitors when added in sufficient quantities, they actually enhance the rate of hydrate formation when added at low concentrations to the water. Furthermore, the presence of these chemicals seems to affect the size of the forming hydrate particles.

Yousif, M.H.

1996-12-31T23:59:59.000Z

439

Challenges, uncertainties and issues facing gas production from gas hydrate deposits  

E-Print Network [OSTI]

combining the material balance equation with the diffusivitya material (and energy balance) balance equation that allows

Moridis, G.J.

2011-01-01T23:59:59.000Z

440

Challenges, uncertainties and issues facing gas production from gas hydrate deposits  

E-Print Network [OSTI]

Petroleum System (TPS), including hydrocarbon source rocks (source-rock type and maturation and hydrocarbon generation

Moridis, G.J.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gas hydrate dynamics" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Challenges, uncertainties and issues facing gas production from gas hydrate deposits  

E-Print Network [OSTI]

M. , Yokoi, K. 2008. Resource assessment of methane hydrategoal because other resource assessment studies in northerntargets. Since 2008, resource assessment of GH in this mode

Moridis, G.J.

2011-01-01T23:59:59.000Z

442

Water dynamics clue to key residues in protein folding  

SciTech Connect (OSTI)

A computational method independent of experimental protein structure information is proposed to recognize key residues in protein folding, from the study of hydration water dynamics. Based on all-atom molecular dynamics simulation, two key residues are recognized with distinct water dynamical behavior in a folding process of the Trp-cage protein. The identified key residues are shown to play an essential role in both 3D structure and hydrophobic-induced collapse. With observations on hydration water dynamics around key residues, a dynamical pathway of folding can be interpreted.

Gao, Meng [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China)] [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China); Zhu, Huaiqiu, E-mail: hqzhu@pku.edu.cn [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China)] [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China); Yao, Xin-Qiu [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China) [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China); Department of Biophysics, Kyoto University, Sakyo Kyoto 606-8502 (Japan); She, Zhen-Su, E-mail: she@pku.edu.cn [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China)] [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China)

2010-01-29T23:59:59.000Z

443

Methane Hydrate Field Program: Development of a Scientific Plan for a Methane Hydrate-Focused Marine Drilling, Logging and Coring Program  

SciTech Connect (OSTI)

This topical report represents a pathway toward better understanding of the impact of marine methane hydrates on safety and seafloor stability and future collection of data that can be used by scientists, engineers, managers and planners to study climate change and to assess the feasibility of marine methane hydrate as a potential future energy resource. Our understanding of the occurrence, distribution and characteristics of marine methane hydrates is incomplete; therefore, research must continue to expand if methane hydrates are to be used as a future energy source. Exploring basins with methane hydrates has been occurring for over 30 years, but these e?orts have been episodic in nature. To further our understanding, these e?orts must be more regular and employ new techniques to capture more data. This plan identifies incomplete areas of methane hydrate research and o?ers solutions by systematically reviewing known methane hydrate “Science Challenges” and linking them with “Technical Challenges” and potential field program locations.

Collett, Tim; Bahk, Jang-Jun; Frye, Matt; Goldberg, Dave; Husebo, Jarle; Koh, Carolyn; Malone, Mitch; Shipp, Craig; Torres, Marta; Myers, Greg; Divins, David; Morell, Margo

2013-11-30T23:59:59.000Z

444

Conference on natural gas use state regulation and market dynamics in the Post 636/Energy Policy Act Era: Proceedings  

SciTech Connect (OSTI)

Reports in this Record of Proceedings explore a wide variety of issues related to the regulation of natural gas and its future role as one of the critical fuels that powers the economy of the United States. The focus is mainly on problems, obstacles, barriers, and the incredibly complex system created to bring a fuel from wellhead to burner tip. Individual papers have been cataloged separately.

Not Available

1993-08-01T23:59:59.000Z

445

Photoelectron Spectroscopy of Cold Hydrated Sulfate Clusters...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

sulfate clusters SO42-(H2O)n (n ) 4-7) at 12 K and ab initio studies to understand the structures and dynamics of these unique solvated systems. A significant increase of...

446

New techniques for monitoring cement hydration under simulated well conditions  

SciTech Connect (OSTI)

Fourier transform infrared spectroscopy and synchrotron X-ray powder diffraction methods are described for studying cement hydration chemistry at temperatures up to 200 C, covering the normal temperature range of wellbore cementing. The methods provide complementary information on the transformation of silicate, ferrite and sulfate minerals. The thermal decomposition of the cement mineral ettringite is shown to occur at 114 C in a sealed system in contact with water. The FTIR spectrum of a well cement slurry hydrating at 150 C and 2,000 psi is analyzed. The anomalous thickening time behavior of certain cements around 75--100 C is discussed in the light of new data on the hydration of a Class G cement at 65 and 95 C, with and without retarder.

Luke, K.; Hall, C.; Jones, T. [Schlumberger Cambridge Research (United Kingdom); Barnes, P.; Turillas, X.; Lewis, A. [Univ. of London (United Kingdom). Birkbeck College

1995-11-01T23:59:59.000Z

447

Protein structure and hydration probed by SANS and osmotic stress  

SciTech Connect (OSTI)

Interactions governing protein folding, stability, recognition, and activity are mediated by hydration. Here, we use small-angle neutron scattering coupled with osmotic stress to investigate the hydration of two proteins, lysozyme and guanylate kinase (GK), in the presence of solutes. By taking advantage of the neutron contrast variation that occurs upon addition of these solutes, the number of protein-associated (solute-excluded) water molecules can be estimated from changes in both the zero-angle scattering intensity and the radius of gyration. Poly(ethylene glycol) exclusion varies with molecular weight. This sensitivity can be exploited to probe structural features such as the large internal GK cavity. For GK, small-angle neutron scattering is complemented by isothermal titration calorimetry with osmoticstress to also measure hydration changes accompanying ligand binding. These results provide a framework for studying other biomolecular systems and assemblies using neutron scattering together with osmotic stress.

Rau, Dr. Donald [National Institutes of Health

2008-01-01T23:59:59.000Z

448

Effects of Hydration and Oxygen Vacancy on CO2 Adsorption and...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Hydration and Oxygen Vacancy on CO2 Adsorption and Activation on ?-Ga2O3(100). Effects of Hydration and Oxygen Vacancy on CO2 Adsorption and Activation on ?-Ga2O3(100)....

449

NISTIR 7232 CEMHYD3D: A Three-Dimensional Cement Hydration  

E-Print Network [OSTI]

NISTIR 7232 CEMHYD3D: A Three-Dimensional Cement Hydration and Microstructure Development Modeling Package. Version 3.0 Dale P. Bentz #12;NISTIR 7232 CEMHYD3D: A Three-Dimensional Cement Hydration

Bentz, Dale P.

450

The dynamics of the early universe and the initial conditions for inflation in a model with radiation and a Chaplygin gas  

E-Print Network [OSTI]

The modeling of the early universe is done through the quantization of a Friedmann-Robertson-Walker model with positive curvature. The material content consists of two fluids: radiation and Chaplygin gas. The quantization of these models is made by following the Wheeler and DeWitt's prescriptions. Using the Schutz formalism, the time notion is recovered and the Wheeler-DeWitt equation transforms into a time dependent Schr\\"{o}dinger equation, which rules the dynamics of the early universe, under the action of an effective potential $V_{ef}$. Using a finite differences method and the Crank-Nicholson scheme, in a code implemented in the program OCTAVE, we solve the corresponding time dependent Schr\\"{o}dinger equation and obtain the time evolution of a initial wave packet. This wave packet satisfies appropriate boundary conditions. The calculation of the tunneling probabilities shows that the universe may emerge from the Planck era to an inflationary phase. It also shows that, the tunneling probability is a function of the mean energy of the initial wave packet and of two parameters related to the Chaplygin gas. We also show a comparison between these results and those obtained by the WKB approximation.

G. A. Monerat; G. Oliveira-Neto; E. V. Corręa Silva; L. G. Ferreira Filho; P. Romildo Jr.; J. C. Fabris; R. Fracalossi; F. G. Alvarenga; S. V. B. Gonçalves

2007-04-19T23:59:59.000Z

451

Electrical properties of polycrystalline methane hydrate Wyatt L. Du Frane,1  

E-Print Network [OSTI]

). CH4 hydrate formation requires cool temperature, high pressure, and sufficient supplies of H2O and CH

Constable, Steve

452

The Structure and Transport of Water and Hydrated Ions Within Hydrophobic, Nanoscale Channels  

SciTech Connect (OSTI)

The purpose of this project includes an experimental and modeling investigation into water and hydrated ion structure and transport at nanomaterials interfaces. This is a topic relevant to understanding the function of many biological systems such as aquaporins that efficiently shuttle water and ion channels that permit selective transport of specific ions across cell membranes. Carbon nanotubes (CNT) are model nanoscale, hydrophobic channels that can be functionalized, making them artificial analogs for these biological channels. This project investigates the microscopic properties of water such as water density distributions and dynamics within CNTs using Nuclear Magnetic Resonance (NMR) and the structure of hydrated ions at CNT interfaces via X-ray Absorption Spectroscopy (XAS). Another component of this work is molecular simulation, which can predict experimental measurables such as the proton relaxation times, chemical shifts, and can compute the electronic structure of CNTs. Some of the fundamental questions this work is addressing are: (1) what is the length scale below which nanoscale effects such as molecular ordering become important, (2) is there a relationship between molecular ordering and transport?, and (3) how do ions interact with CNT interfaces? These are questions of interest to the scientific community, but they also impact the future generation of sensors, filters, and other devices that operate on the nanometer length scale. To enable some of the proposed applications of CNTs as ion filtration media and electrolytic supercapacitors, a detailed knowledge of water and ion structure at CNT interfaces is critical.

Holt, J K; Herberg, J L; Wu, Y; Schwegler, E; Mehta, A

2009-06-15T23:59:59.000Z

453

Structure of hydrophobic hydration of benzene and hexafluorobenzene from first principles  

SciTech Connect (OSTI)

We report on the aqueous hydration of benzene and hexafluorobenzene, as obtained by carrying out extensive (>100 ps) first principles molecular dynamics simulations. Our results show that benzene and hexafluorobenzene do not behave as ordinary hydrophobic solutes, but rather present two distinct regions, one equatorial and the other axial, that exhibit different solvation properties. While in both cases the equatorial regions behave as typical hydrophobic solutes, the solvation properties of the axial regions depend strongly on the nature of the {pi}-water interaction. In particular, {pi}-hydrogen and {pi}-lone pair interactions are found to dominate in benzene and hexafluorobenzene, respectively, which leads to substantially different orientations of water near the two solutes. We present atomic and electronic structure results (in terms of Maximally Localized Wannier Functions) providing a microscopic description of benzene- and hexafluorobenzene-water interfaces, as well as a comparative study of the two solutes. Our results point at the importance of an accurate description of interfacial water in order to characterize hydration properties of apolar molecules, as these are strongly influenced by subtle charge rearrangements and dipole moment redistributions in interfacial regions.

Allesch, M; Schwegler, E; Galli, G

2006-10-23T23:59:59.000Z

454

Impacts of ocean acidification and mitigative hydrated lime addition on Pacific oyster larvae  

E-Print Network [OSTI]

Impacts of ocean acidification and mitigative hydrated lime addition on Pacific oyster larvae, and for other species. Keywords: Ocean acidification; Pacific oyster; Larval stages; Hydrated lime; Shellfish No.: 577 Title of Project: Impacts of ocean acidification and mitigative hydrated lime additio