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1

Atmospheric chemistry of hydrofluorocarbon 134a. Fate of the alkoxy radical CF{sub 3}O  

SciTech Connect (OSTI)

The atmospheric chemistry of the alkoxy radical CF{sub 3}O produced in the photooxidation of hydrofluorocarbon (HFC) 134a has been investigated using Fourier transform infrared spectroscopy. CF{sub 3}O radicals are shown to react with methane and CF{sub 3}CFH{sub 2} to give CF{sub 3}OH. CF{sub 3}OH decomposes to give COF{sub 2} and HF. The rate constant for the reaction CF{sub 3}O + CF{sub 3}CFH{sub 2} (HFC-134a) {r_arrow} CF{sub 3}OH + CF{sub 3}CFH was determined to be k{sup 19} = (1.1 {plus_minus} 0.7) x 10{sup -15} cm{sup 3} molecule{sup -1}s{sup -1} at 297 K. The implications of our results for the atmospheric chemistry of CF{sub 3}O radicals and HFC-134a are discussed. 26 refs., 4 figs., 2 tabs.

Sehested, J. [Riso National Lab. (Denmark); Wallington, T.J. [Ford Motor Company, Dearborn, MI (United States)

1993-01-01T23:59:59.000Z

2

Viscosity of Gaseous HFC245fa  

Science Journals Connector (OSTI)

Viscosity of Gaseous HFC245fa ... The uncertainty of the reported viscosities was estimated to be within 2.0 % with a coverage factor of k = 2. ...

Xiaopo Wang; Jiangtao Wu; Zhigang Liu

2009-07-10T23:59:59.000Z

3

HFC supermarket refrigeration demonstration. Phases 1 and 2  

SciTech Connect (OSTI)

The HFC Supermarket Refrigeration Demonstration tested and evaluated HFC refrigerants in a new Shop `n Save supermarket in Glens Falls, New York. This project included laboratory testing of HFC refrigerants for medium- and low-temperature application, the design of a supermarket refrigeration system to accommodate the new refrigerants, installation, start-up, and field monitoring.

Borhanian, H.; Rafuse, L.

1996-04-01T23:59:59.000Z

4

Enhanced naphthenic refrigeration oils for household refrigerator systems  

SciTech Connect (OSTI)

Due to industry concerns about the successful employment of hydrofluorocarbon-immiscible hydrocarbon oils in refrigeration systems, enhanced naphthenic refrigeration oils have been developed. These products have been designed to be more dispersible with hydrofluorocarbon (HFC) refrigerants, such as R-134a, in order to facilitate lubricant return to the compressor and to ensure proper energy efficiency of the system. Bench tests and system performance evaluations indicate the feasibility of these oils for use in household refrigeration applications. Results of these evaluations are compared with those obtained with polyol esters and typical naphthenic mineral oils employed in chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) refrigeration applications.

Reyes-Gavilan, J.L.; Flak, G.T.; Tritcak, T.R. [Witco Corp., Oakland, NJ (United States); Barbour, C.B. [Americold, Cullman, AL (United States)

1997-12-31T23:59:59.000Z

5

Viscosity of gaseous ethyl fluoride (HFC-161)  

Science Journals Connector (OSTI)

Abstract The paper describes an improved Maxwell type oscillating-disk viscometer. The experimental system was calibrated by argon, carbon dioxide, nitrogen, hydrogen and verified by nitrogen. The viscosities of gaseous HFC-161 were measured from 293K to 369K at pressures from 0.1MPa up to the saturated vapor pressure. An empirical viscosity equation is proposed to interpolate the present experimental data as a function of density and temperature. The uncertainty of the reported viscosity was estimated to be within 1%.

Shaohua Lv; Xiaoming Zhao; Chuanqi Yao; Wei Wang; Zhikai Guo

2014-01-01T23:59:59.000Z

6

Atmospheric Fluoroform (CHF3, HFC-23) at Cape Grim, Tasmania  

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

CHF3, HFC-23 at Cape Grim, Tasmania CHF3, HFC-23 at Cape Grim, Tasmania Atmospheric Fluoroform (CHF3, HFC-23) at Cape Grim, Tasmania graphics Graphics data Data Authors D. E. Oram,1 W. T. Sturges,1 S. A. Penkett,1 A. McCulloch,2 and P. J. Fraser3 1School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, United Kingdom 2ICI Chemicals & Polymers Ltd., Safety and Environment Department, Runcorn, Cheshire, WA7 4QD, United Kingdom 3CRC for Southern Hemisphere Meteorology, Division of Atmospheric Research, Commonwealth Scientific and Industrial Research Organization, Private Bag No. 1, Aspendale, Victoria 3195, Australia Period of Record 1978-1995 Methods The sampling and analytical methods are described more fully in Oram et al. (1998). In summary, air samples were taken from the archive of Cape Grim,

7

HFC-6000 for Nuclear I and C Upgrade  

SciTech Connect (OSTI)

The scalability of the HFC-6000 product line makes it an effective solution for nuclear power plant I and C upgrade applications. Its 19-in. rack-mounted platform provides a modular structure whose components can be used for many different nuclear power plant safety applications. This single-platform solution reduces the overall complexity of I and C implementation by minimizing operational and maintenance requirements. The HFC-6000 product line is designed to operate with either single or multiple control remote units in each channel. The main controller module in a remote unit is the system controller (HFCSBC06), which executes control logic programs, I/O scan, and C-Link communication. All three functions are handled by dedicated 64/32-bit microprocessors. A redundant configuration of system controllers consists of two HFC-SBC06 modules and one HFC-DPM06 dual-ported memory module. The hardware interface with external peripheral equipment is provided by an HFC-PCC06 peripheral interface module in the same rack. This module communicates with dedicated Control Switch Modules (the operator interface for digital control) and M/A stations (the operator interface for analog control), which are mounted on the plant main control board. Individual input/output modules serve as the hardware interface with the field devices under control and are implemented by different types of I/O modules. Each I/O module has a redundant serial communication interface. This serial interface employs a proprietary poll-response intercommunication link (ICL) protocol for communication with the system controllers. When a remote is configured with redundant controllers, the two ICL interfaces on each I/O module are connected to separate system controllers to create a redundant link. The I/O modules can be installed locally or remotely. If the I/O modules are physically remote from the controller, the ICL can be implemented with fiber optics to provide physical and electrical isolation from non-safety components. An HFC-FPD06 Flat Panel Display Module can be used as a human-machine interface (HMI). This HMI is composed of a qualified flat panel display and an HFC-FPC06 FPD controller. The FPC06 module has hardware interfaces for both the ICL and the fast Ethernet C-Link. It is configured as a subordinate to the HFC-SBC06 system controller and controls graphic displays on the HMI; it can also perform data voting and validation functions for redundant or triple redundant safety channels. The HFC-FPC06 can be used in either single or redundant configurations. The Power Supply Module consists of a redundant, rack-mounted power supply set. The typical configuration provides 24-vdc for all logic functions and 48-vdc for excitation power. Individual power supplies are redundant and hot swappable. Currently, HFC-6000 system is being installed in Kori Units no.1 to no.4 for its AAC D/G control and monitoring system and several other NPP I and C upgrade projects. (authors)

Taylor, Jonathan; Hsu, Allen; Gerardis, Terry; Stevens, John; McCreary, Tim; Yang, Steve [HF Controls Corporation, 16650 Westgrove Dr., Suite 500s (United States)

2006-07-01T23:59:59.000Z

8

HFC-134A and HCFC-22 supermarket refrigeration demonstration and laboratory testing. Phase I. Final report  

SciTech Connect (OSTI)

Aspen Systems and a team of nineteen agencies and industry participants conducted a series of tests to determine the performance of HFC-134a, HCFC-22, and CFC-502 for supermarket application. This effort constitutes the first phase of a larger project aimed at carrying out both laboratory and demonstration tests of the most viable HFC refrigerants and the refrigerants they replace. The results of the Phase I effort are presented in the present report. The second phase of the project has also been completed. It centered on testing all viable HFC replacement refrigerants for CFC-502. These were HFC-507, HFC-404A, and HFC-407A. The latter results are published in the Phase II report for this project. As part of Phase I, a refrigeration rack utilizing a horizontal open drive screw compressor was constructed in our laboratory. This refrigeration rack is a duplicate of one we have installed in a supermarket in Clifton Park, NY.

NONE

1996-04-01T23:59:59.000Z

9

Reduced-temperature processing and consolidation of ultra-refractory Ta4HfC5  

SciTech Connect (OSTI)

TaC, HfC, and WC powders were subjected to high-energy milling and hot pressing to produce Ta4HfC5, a composite of Ta(4)HfC5 + 30 vol.% WC, and a composite of Ta4HfC5 + 50 vol.% WC. Sub-micron powders were examined after four different milling intervals prior to hot pressing. XRD was used to verify proper phase formation. SEM, relative density, and hardness measurements were used to examine the resulting phases. Hot pressed compacts of Ta4HfC5 showed densification as high as 98.6% along with Vickers hardness values of 21.4 GPa. Similarly, Ta4HfC5 + 30 vol.% WC exhibited 99% densification with a Vickers hardness of 22.5 GPa. These levels of densification were achieved at 1500 degrees C, which is lower than any previously reported sintering temperature for Ta4HfC5. Microhardness values measured in this study were higher than those previously reported for Ta4HfC5. The WC additions to Ta4HfC5 were found to improve densification and increase microhardness. (C) 2013 Elsevier Ltd. All rights reserved.

Gaballa, Osama [Ames Laboratory; Cook, B. A. [TRI International; Russell, A. M. [Ames Laboratory

2013-04-26T23:59:59.000Z

10

Electronic Structure of Hf@C28 and Its Ions. 1. SCF Calculations  

Science Journals Connector (OSTI)

Electronic Structure of Hf@C28 and Its Ions. 1. SCF Calculations ... Electronic Structures of C28H4 and Hf@C28H4 and Their Ions. ... Electronic structure calculations, including relativistic core potentials and the spin?orbit interaction, have been carried out on the C28, Pa@C28, and U@C28 species. ...

Debbie Fu-Tai Tuan; Russell M. Pitzer

1995-01-01T23:59:59.000Z

11

HFC-23 (CHF3) emission trend response to HCFC-22 (CHClF2) production and recent HFC-23 emission abatement measures  

E-Print Network [OSTI]

HFC-23 (also known as CHF3 [CHF subscript 3], fluoroform or trifluoromethane) is a potent greenhouse gas (GHG), with a global warming potential (GWP) of 14 800 for a 100-year time horizon. It is an unavoidable by-product ...

Miller, B. R.

12

Buildings Energy Data Book: 5.3 Heating, Cooling, and Ventilation Equipment  

Buildings Energy Data Book [EERE]

4 4 Halocarbon Environmental Coefficients and Principal Uses 100-Year Global Ozone Depletion Warming Potential Potential (ODP) Compound (CO2 = 1) (Relative to CFC-11) Principal Uses Chlorofluorocarbons CFC-11 1.00 Blowing Agent, Chillers CFC-12 (1) 1.00 Auto A/C, Chillers, & Blowing Agent CFC-113 0.80 Solvent CFC-114 1.00 Solvent CFC-115 (2) 0.60 Solvent, Refrigerant Hydrochlorofluorocarbons HCFC-22 (2) 0.06 Residential A/C HCFC-123 0.02 Refrigerant HCFC-124 0.02 Sterilant HCFC-141b 0.11 CFC Replacement HCFC-142b 0.07 CFC Replacement Bromofluorocarbons Halon-1211 3.00 Fire Extinguishers Halon-1301 10.00 Fire Extinguishers Hydrofluorocarbons HFC-23 0.00 HCFC Byproduct HFC-125 0.00 CFC/HCFC Replacement HFC-134a 0.00 Auto A/C, Refrigeration HFC-152a (1) 0.00 Aerosol Propellant HFC-227ea 0.00 CFC Replacement

13

Evaluation of HFC-245ca for commercial use in low pressure chillers. Final report, Volume I  

SciTech Connect (OSTI)

Federal regulations banned the production of CFC-11 on January 1, 1996. HCFC-123, the only commercial alternative, will be limited to service applications after January 1, 2020 and will be eliminated from production on January 1, 2030. HFC-245ca has been identified as a potential replacement for CFC-11 in retrofit applications and for HCFC-123 in new chillers, but the marginal flammability of HFC-245ca is a major obstacle to its commercial use as a refrigerant in the United States. This report assesses the commercial viability of HFC-245ca based on its experimental performance in a direct drive low pressure centrifugal chiller exclusive of its flammability characteristics. Three different impeller diameters were tested in the chiller, with all impellers having identical discharge blade angles. Experimental work included tests in a 200 ton 3 stage direct drive chiller with 3 impeller sets properly sized for each of three refrigerants, CFC-11, HCFC-123, and HFC-245ca. The commercial viability assessment focused on both retrofit and new product performance and cost.

Keuper, E.F. [Trane Co., LaCrosse, WI (United States)] [Trane Co., LaCrosse, WI (United States)

1996-03-01T23:59:59.000Z

14

Two-Phase Flow of HCFC-22 and HFC-134a through Short Tube Orifices  

E-Print Network [OSTI]

HCFC-22 and HFC-134a were used with short tube orifices having length to diameter ratios ranging from 5 to 20 in a 9.53 mm (3/8 in.) refrigerant line to investigate both two-phase and subcooled liquid flow entering the short tubes. Flow temperature...

Yongchan, K.

2008-01-23T23:59:59.000Z

15

Electronic Structures of C28H4 and Hf@C28H4 and Their Ions. SCF Calculations  

Science Journals Connector (OSTI)

In our calculations, we use the ab initio restricted Hartree?Fock (SCF) and configuration interaction (CI) methods to study the electronic structure respectively excluding and including electron correlation and the spin?orbit interaction. ... Systems of Calculation. ... The molecular integrals were calculated once for C28H4 (or Hf@C28H4) and stored on disk for all the SCF calculations of the neutral molecule and ions of C28H4 (or Hf@C28H4). ...

Debbie Fu-Tai Tuan; Russell M. Pitzer

1996-04-11T23:59:59.000Z

16

Determination of properties of PVE lubricants with HFC refrigerants[PolyVinylEther  

SciTech Connect (OSTI)

Polyalkyleneglycol (PAG) and polyol ester (POE) have been developed as refrigeration lubricants, used with HFC134a. PAG is used for automotive air conditioning systems and POE is used for domestic reciprocating refrigerators and for A/C systems. Although PAG exhibits good lubricity performance, it is difficult to use for domestic reciprocating refrigerators due to its low dielectric property. POE is difficult to use for automotive A/C systems, due to hydrolysis and poor lubricity performance. Polyvinylether (PVE) can be used in place of PAG and POE with HFC refrigerants. PVE is used for A/C systems as well as refrigerator and freezer applications. PVE is an ideal lubricant for use with HFCs.

Kaneko, Masato; Sakanoue, Shuichi; Tazaki, Toshihiro; Tominaga, Shoichi; Takagi, Minoru; Goodin, M.

1999-07-01T23:59:59.000Z

17

An Experimental Investigaton of the Effect of Oil on Convective Heat Trasfer and Pressure Drop of a HFC-32/HRC-125 Mixture  

E-Print Network [OSTI]

The heat transfer coefficients and pressure drops of HCFC-22 and a 50% mass mixture of HFC-32/HFC-125 were experimentally measured under flow boiling conditions in a smooth tube. The refrigerants were flowed through an 8 mm diameter smooth tube...

McJimsey, Bert Ashford

18

Experimental evaluation of automotive air-conditioning using HFC-134a and HC-134a  

Science Journals Connector (OSTI)

An experimental study to evaluate the energy consumption of an automotive air conditioning is presented. In this study these refrigerants will be tested using the experimental rig which simulated the actual cars as a cabin complete with a cooling system component of the actual car that is as the blower evaporator condenser radiators electric motor which acts as a vehicle engine and then the electric motor will operate the compressor using a belt and pulley system as well as to the alternator will recharge the battery. The compressor working with the fluids HFC-134a and HC-134a and has been tested varying the speed in the range 1000 1500 2000 and 2500 rpm. The measurements taken during the one hour experimental periods at 2-minutes interval times for temperature setpoint of 20C with internal heat loads 0 500 700 and 1000 W. The final results of this study show an overall better energy consumption of the HFC-134a compared with the HC-134a.

Azhar Abdul Aziz

2012-01-01T23:59:59.000Z

19

Design and simulation of a heat pump for simultaneous heating and cooling using HFC or CO2  

E-Print Network [OSTI]

1 Design and simulation of a heat pump for simultaneous heating and cooling using HFC or CO2: +33 2 23 23 42 97 Fax: +33 2 23 23 40 51 ABSTRACT This article presents a Heat Pump for Simultaneous heat pump i in is isentropic mec mechanical nof without frosting o out r refrigerant S sublimation sc

Paris-Sud XI, Université de

20

Comparative analysis of CO2-based transcritical Rankine cycle and HFC245fa-based subcritical organic Rankine cycle using low-temperature geothermal source  

Science Journals Connector (OSTI)

A detailed thermodynamic and techno-economic comparison is presented for a CO2-based transcritical Rankine cycle and a subcritical organic Rankine cycle (ORC) using HFC245fa (1,1,1 ... a minimum investment. The e...

Tao Guo; HuaiXin Wang; ShengJun Zhang

2010-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydrochlorofluorocarbon hfc hydrofluorocarbon" 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

A review of lubrication and preformance issues in refrigeration systems using an HFC (R-134a) refrigerant  

SciTech Connect (OSTI)

It has been considered critical for refrigerant and compressor lubricant to be miscible with each other over part of the range of operating conditions of refrigerant systems. Adequate miscibility, many believe, provides oil return to the compressor. Presently, synthetic polyol esters have been selected for use with HFC refrigerants, such as R-134a, which are considered appropriate alternatives to CFCs. The authors will review the mechanical issues in miscible vs non-miscible naphthenic hydrocarbon oil-based lubricants. Extensive lab, test stand and cabinet testing has been conducted and data will be presented which show responsible and predictable performance based on the chemical and physical properties of the lubricant and refrigerant. Many non-miscible systems show satisfactory performance with the proper selection of lubricant, additives and mechanical configuration. 3 refs., 3 figs., 5 tabs.

Reyes-Gavilan, J.; Eckard, A.; Flak, T.; Tritak, T. [Witco Corporation, Oakland, NJ (United States)

1996-04-01T23:59:59.000Z

22

Buildings Energy Data Book: 5.3 Heating, Cooling, and Ventilation Equipment  

Buildings Energy Data Book [EERE]

6 6 Estimated U.S. Emissions of Halocarbons, 1987-2001 (MMT CO2 Equivalent) Gas 1987 1990 1992 1995 1998 2000 2001 Chlorofluorocarbons CFC-11 391 246 207 167 115 105 105 CFC-12 1,166 1,194 853 549 223 182 226 CFC-113 498 158 103 52 0 0 0 CFC-114 N.A. 46 29 16 1 N.A. N.A. CFC-115 N.A. 30 27 22 19 N.A. N.A. Bromofluorocarbons Halon-1211 N.A. 1 1 1 1 N.A. N.A. Halon-1301 N.A. 12 12 12 13 N.A. N.A. Hydrochlorofluorocarbons HCFC-22 116 136 135 123 128 134 137 HCFC-123 N.A. 0 0 0 0 N.A. N.A. HCFC-124 0 0 0 3 4 N.A. N.A. HCFC-141b N.A. 0 0 14 19 4 4 HCFC-142b N.A. 0 2 18 22 26 26 Hydrofluorocarbons HFC-23 48 36 36 28 41 31 22 HFC-125 N.A. 0 1 2 4 5 6 HFC-134a N.A. 1 1 19 35 44 41 Total 2,219 1,861 1,408 1,024 624 532 566 Source(s): Intergovernmental Panel for Climate Change, Climate Change 2001: The Scientific Basis, Jan. 2001, Table 3, p. 47 for GWPs; EIA, Emissions of Greenhouse Gases in the U.S. 2001, Dec. 2002, Table 29, p. 71 and Table D2, p. D-5 for 1990-2001 emissions; EPA, Inventory of U.S. Greenhouse Gas Emissions and

23

Atmospheric chemistry of HFC-134a. Kinetic and mechanistic study of the CF[sub 3]CFHO[sub 2] + HO[sub 2] reaction  

SciTech Connect (OSTI)

Rate constant measurements for the title reaction and for F + CF[sub 3]CFH[sub 2] are reported over the 210-363 K temperature range. Reacting mixtures of CF[sub 3]CFHO[sub 2] and HO[sub 2] radicals are created by the flash photolysis of F[sub 2] in the presence of HFC-134a (CF[sub 3]CFH[sub 2]), H[sub 2], and O[sub 2] and are probed by time-resolved UV absorption spectroscopy. The deconvolution of spectra taken at various delay times provides concentration versus time profiles for the respective radical species. A comparison of the initial CF[sub 3]CFHO[sub 2] and HO[sub 2] concentrations yields a relative rate determination of k[sub 1] = (9.8[sub [minus]5][sup +9]) x 10[sup [minus]11]e[sup (1130[+-]190)/T] cm[sup 3] s[sup [minus]1] for the F + CF[sub 3]CFH[sub 2] rate constant. A simultaneous fit of the radical decay curves to a mechanism containing the known HO[sub 2] self-reaction kinetics, the previously determined CF[sub 3]CFHO[sub 2] self-reaction mechanism, and a cross reaction between these species yields a rate constant of k[sub 7] = (1.8[sub [minus]1.0][sup +2.4]) x 10[sup [minus]13]e[sup (910[+-]220)/T] cm[sup 3] s[sup [minus]1] for the HO[sub 2] + CF[sub 3]CFHO[sub 2] reaction. A product study at 296 K by Fourier transform infrared spectroscopy reveals that less than 5% of the product appears as CF[sub 3]C(O)F. By inference >95% of the reaction gives the hydroperoxide CF[sub 3]CFHOOH. 34 refs., 7 figs., 4 tabs.

Maricq, M.M.; Szente, J.J.; Hurley, M.D.; Wallington, T.J. (Ford Motor Company, Dearborn, MI (United States))

1994-09-08T23:59:59.000Z

24

Final Technical Report HFC Concrete: A Low-???????­???¢???????Energy, Carbon-???????­Dioxide-???????­Negative Solution for reducing Industrial Greenhouse Gas Emissions  

SciTech Connect (OSTI)

Solidia/CCSM received funding for further research and development of its Low Temperature Solidification Process (LTS), which is used to create hydrate-free concrete (HFC). LTS/HFC is a technology/materials platform that offers wide applicability in the built infrastructure. Most importantly, it provides a means of making concrete without Portland cement. Cement and concrete production is a major consumer of energy and source of industrial greenhouse gas (GHG) emissions. The primary goal of this project was to develop and commercialize a novel material, HFC, which by replacing traditional concrete and cement, reduces both energy use and GHG emissions in the built infrastructure. Traditional concrete uses Portland Cement (PC) as a binder. PC production involves calcination of limestone at {approx}1450 C, which releases significant amounts of CO{sub 2} gas to the atmosphere and consumes a large amount of energy due to the high temperature required. In contrast, HFC is a carbonate-based hydrate-free concrete (HFC) that consumes CO{sub 2} gas in its production. HFC is made by reaction of silicate minerals with CO{sub 2} at temperatures below 100 C, more than an order-of-magnitude below the temperature required to make PC. Because of this significant difference in temperature, it is estimated that we will be able to reduce energy use in the cement and concrete industry by up to 30 trillion Btu by 2020. Because of the insulating properties of HFC, we believe we will also be able to significantly reduce energy use in the Building sector, though the extent of this saving is not yet quantified. It is estimated that production of a tonne of PC-based concrete requires about 6.2 million Btu of energy and produces over 1 tonne of CO{sub 2} emissions (Choate, 2003). These can be reduced to 1.9 million Btu and 0.025 tonnes of CO{sub 2} emissions per tonne of HFC (with overall CO{sub 2}-negativity possible by increasing carbonation yield). In this way, by replacing PC-based concrete with HFC in infrastructure we can reduce energy use in concrete production by 70%, and reduce CO{sub 2} emissions by 98%; thus the potential to reduce the impact of building materials on global warming and climate change is highly significant. Low Temperature Solidification (LTS) is a breakthrough technology that enables the densification of inorganic materials via a hydrothermal process. The resulting product exhibits excellent control of chemistry and microstructure, to provide durability and mechanical performance that exceeds that of concrete or natural stone. The technology can be used in a wide range of applications including facade panels, interior tiles, roof tiles, countertops, and pre-cast concrete. Replacing traditional building materials and concrete in these applications will result in significant reduction in both energy consumption and CO{sub 2} emissions.

Dr. Larry McCandlish, Principal Investigator; Dr. Richard Riman, Co-Principal Investigator

2012-05-14T23:59:59.000Z

25

Recent increases in global HFC-23 emissions  

E-Print Network [OSTI]

Sustainability, Technical University Eindhoven, Eindhoven, Netherlands. Department of Physics and Astronomy, Bowdoin College,

2010-01-01T23:59:59.000Z

26

Recent increases in global HFC-23 emissions  

E-Print Network [OSTI]

2009), Greenhouse Gas Emissions Data, http://unfccc.int/ghg_data/ ghg_data_unfccc/items/4146.php, U. N. Framework Conv.

2010-01-01T23:59:59.000Z

27

Recent increases in global HFC-23 emissions  

E-Print Network [OSTI]

Missions History C E1 d E2 d F1 e F2 e F3 e G H SPO01 WAIS-Best-fitting histories (C, F1, F2, G, K2) are shown as red

2010-01-01T23:59:59.000Z

28

Atmospheric chemistry of HFC-227ca: Spectrokinetic investigation of the CF{sub 3}CF{sub 2}CF{sub 2}O{sub 2} radical, its reactions with NO and NO{sub 2}, and the atmospheric fate of the CF{sub 3}CF{sub 2}CF{sub 2}O radical  

SciTech Connect (OSTI)

A pulse radiolysis technique was used to study the UV absorption spectrum of CF{sub 3}CF{sub 2}CF{sub 2}O{sub 2} radicals, at 230 nm {sigma} = (3.2{+-}0.4) x 10{sup -18} cm{sup 2} molecule{sup -1}. Rate constants for reactions of CF{sub 3}CF{sub 2}CF{sub 2}O{sub 2} radicals with NO and NO{sub 2} were determined. The rate constant for reaction of F atoms with CF{sub 3}CF{sub 2}CF{sub 2}H was determined by using an absolute rate technique. The atmospheric fate of CF{sub 3}CF{sub 2}CF{sub 2}O radicals is decomposition via C-C bond scission to give CF{sub 3}CF{sub 2} radicals and CF{sub 2}O. In one bar of SF{sub 6} at 296 K, CF{sub 3}CF{sub 2}CF{sub 2}O radicals decompose with a rate > 1.5 x 10{sup 5} s{sup -1}. In their turn CF{sub 3}CF{sub 2} radicals are converted into CF{sub 3}CF{sub 2}O radicals which also decompose via C-C bond scission. The results are discussed with respect to the atmospheric chemistry of HFC-227ca. 30 refs., 12 figs., 1 tab.

Geissing, A.M.B.; Feilberg, A.; Mogelberg, T.E.; Sehested, J.; Bilde, M. [Riso National Lab., Roskilde (Denmark)] [Riso National Lab., Roskilde (Denmark); Wallington, T.J. [Ford Motor Co., Dearborn, MI (United States)] [Ford Motor Co., Dearborn, MI (United States); Nielsen, O.J. [Ford Motor Co., Aachen (Germany)] [Ford Motor Co., Aachen (Germany)

1996-04-18T23:59:59.000Z

29

Atmospheric chemistry of HFC-143a: Spectrokinetic investigation of the CF[sub 3]CH[sub 2]O[sub 2][center dot] radical, its reactions with NO and NO[sub 2], and the fate of CF[sub 3]CH[sub 2]O  

SciTech Connect (OSTI)

The ultraviolet absorption spectrum of CF[sub 3]CH[sub 2]O[sub 2] radicals, the kinetics of their self-reaction, and their reactions with NO and NO[sub 2] have been studied in the gas phase at 296 K using a pulse radiolysis technique. A long path-length Fourier transform infrared technique was used to study the fate of CF[sub 3]CH[sub 2]O radicals. Absorption cross sections were quantified over the wavelength range 220-300 nm. At 250 nm, [sigma](CF[sub 3]CH[sub 2]O[sub 2]) = (2.73 [+-] 0.31) [times] 10[sup [minus]18] molecule[sup [minus]1]. By monitoring the rate of NO[sub 2] formation, k[sub 4] = (1.2 [+-] 0.3) [times] 10[sup [minus]11] cm[sup 3] molecule[sup [minus]1] s[sup [minus]1] was found for the reaction of CF[sub 3]CH[sub 2]O[sub 2] radical with NO. The reaction of CF[sub 3]CH[sub 2]O[sub 2] radicals with NO gives CF[sub 3]CH[sub 2]O radicals. In the atmosphere, >99.33% of the CF[sub 3]CH[sub 2]O radicals react with O[sub 2] to give CF[sub 3]CHO. By monitoring the rate of NO[sub 2] decay, k[sub 5] = (5.8 [+-] 1.1) [times] 10[sup [minus]12] cm[sup 3] molecule[sup [minus]1] s[sup [minus]1] was found for the reaction of CF[sub 3]CH[sub 2]O[sub 2] radical with NO[sub 2]. The results are discussed with respect to the atmospheric chemistry of CF[sub 3]CH[sub 3] (HFC-143a). 34 refs., 12 figs., 1 tab.

Nielsen, O.J.; Gamborg, E.; Sehested, J. (Riso National Lab., Roskilde (Denmark)); Wallington, T.J.; Hurley, M.D. (Ford Motor Company, Dearborn, MI (United States))

1994-09-22T23:59:59.000Z

30

Atmospheric chemistry of CF{sub 3}CFHCF{sub 3} (HFC-227ea): Spectrokinetic investigation of the CF{sub 3}CFO{sub 2}{sup .}CF{sub 3} radical, its reactions with NO and NO{sub 2}, and fate of the CF{sub 3}CFO{sup .}CF{sub 3} radical  

SciTech Connect (OSTI)

The ultraviolet absorption spectrum of the CF{sub 3}CFO{sub 2}{sup .}CF{sub 3} radical, the kinetics of its self-reaction and reactions with NO and NO{sub 2} have been studied in the gas phase at 296 K using a pulse radiolysis technique. A long-path-length Fourier transform infrared technique was used to study the fate of the CF{sub 3}CFO{sup .}CF{sub 3} radical. Absorption cross sections for the CF{sub 3}CFO{sub 2}{sup .}CF{sub 3} radical were quantified over the wavelength range 220-270 nm. The rate constant for the CF{sub 3}CFO{sub 2}{sup .}CF{sub 3} self-reaction was determined, as well as those of the reaction of CF{sub 3}CFO{sub 2}{sup .}CF{sub 3} radicals with NO and NO{sub 2}. The atmospheric fate of CF{sub 3}CFO{sup .}CF{sub 3} radicals is decomposition via C-C bond scission to give CF{sub 3} radicals and CF{sub 3}C(O)F. In 1000 mbar of SF{sub 6} at 296 K decomposition of CF{sub 3}CFO{sup .}CF{sub 3} radicals proceeds at a rate greater than 1 x 10{sup 5} s{sup -1}. The results are discussed in the context of the atmospheric chemistry of HFC-227ea. 31 refs., 10 figs., 2 tabs.

Mogelberg, T.E.; Sehested, J.; Bilde, M. [Riso National Lab., Roskilde (Denmark)] [Riso National Lab., Roskilde (Denmark); Wallington, T.J. [Ford Motor Co., Dearborn, MI (United States)] [Ford Motor Co., Dearborn, MI (United States); Nielsen, O.J. [Ford Forschungscenter Aachen (Germany)] [Ford Forschungscenter Aachen (Germany)

1996-05-23T23:59:59.000Z

31

Case Study: Transcritical Carbon Dioxide Supermarket Refrigeration Systems  

Broader source: Energy.gov [DOE]

This case study documents one year of operating experience with a transcritical carbon dioxide (TC CO2) booster refrigeration system at Delhaize Americas Hannaford supermarket location in Turner, Maine. This supermarket, which began operation in June 2013, is the first supermarket installation in the U.S. of a TC CO2 booster refrigeration system. We compare refrigeration system performance to that for a supermarket having nearly identical layout and refrigeration loads, in a similar climate and of similar vintage, that uses a conventional hydrofluorocarbon (HFC) refrigerant. Delhaize provided the submetered and utility data used to generate the performance summaries herein.

32

Reducing the Carbon Footprint of Commercial Refrigeration Systems Using Life Cycle Climate Performance Analysis: From System Design to Refrigerant Options  

SciTech Connect (OSTI)

In this paper, Life Cycle Climate Performance (LCCP) analysis is used to estimate lifetime direct and indirect carbon dioxide equivalent gas emissions of various refrigerant options and commercial refrigeration system designs, including the multiplex DX system with various hydrofluorocarbon (HFC) refrigerants, the HFC/R744 cascade system incorporating a medium-temperature R744 secondary loop, and the transcritical R744 booster system. The results of the LCCP analysis are presented, including the direct and indirect carbon dioxide equivalent emissions for each refrigeration system and refrigerant option. Based on the results of the LCCP analysis, recommendations are given for the selection of low GWP replacement refrigerants for use in existing commercial refrigeration systems, as well as for the selection of commercial refrigeration system designs with low carbon dioxide equivalent emissions, suitable for new installations.

Fricke, Brian A [ORNL] [ORNL; Abdelaziz, Omar [ORNL] [ORNL; Vineyard, Edward Allan [ORNL] [ORNL

2013-01-01T23:59:59.000Z

33

Advanced Insulation for High Performance Cost-effective Wall, Roof, and  

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

Advanced Insulation for High Performance Advanced Insulation for High Performance Cost-effective Wall, Roof, and Foundation Systems Research Project Advanced Insulation for High Performance Cost-effective Wall, Roof, and Foundation Systems Research Project The U.S. Department of Energy (DOE) is currently conducting research into advanced insulation for high performance wall, roof, and foundation systems. Heat flows from hotter to colder spaces, and insulation is designed to resist this flow by keeping hot air out in the summer and in during the winter. Project Description This project seeks to develop high performing, durable, hydrofluorocarbon and hydrochlorofluorocarbons -free insulation with an R-value greater than 7.5-per-inch and a Class A fire performance. Project Partners Research is being undertaken between DOE and Dow Chemical.

34

Atmospheric Measurements of Climate-Relevant Species  

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

Atmospheric Measurements of Climate-Relevant Species Atmospheric Measurements of Climate-Relevant Species CDIAC's data collection includes measurements of the following climate-relevant chemical species. A summary of recent greenhouse gas concentrations is also available. To determine how compounds are named, see the CDIAC "Name that compound" page. Butane (C4H10) Carbon Dioxide (CO2) Carbon Isotopes Carbon Monoxide (CO) Carbon Tetrachloride (CCl4) Chlorofluorocarbons Chloroform (CHCl3) Deuterium (2H) Ethane (C2H6) Ethyl Nitrate (C2H5ONO2) Ethyne (C2H2) Fluoroform (CHF3) Halogenated Compounds (modern records) Halons (fluorocarbons) Hydrogen (H2) Hydrochlorofluorocarbons (HCFCs) Hydrofluorocarbons (HFCs) i-Propyl Nitrate (C3H7ONO2) Methane (CH4) Methyl Bromide (CH3Br) Methyl Chloride (CH3Cl) Methyl Chloroform (CH3CCl3)

35

Evaluation of performance and composition shift of zeotropic mixtures in a Lorenz-Meutzner refrigerator/freezer  

SciTech Connect (OSTI)

Results from previous testing of this refrigerator/freezer using a 750 Btu/h compressor and several zeotropic mixtures revealed a performance enhancement up to 16% above that of hydrofluorocarbon R-134a. In the study presented in this paper, the Lorenz-Meutzner (LM) refrigerator/freezer equipped with a 1060 Btu/h compressor, two evaporators, and two intercoolers was experimentally tested in an environmental chamber according to the Association of Home Appliance Manufacturers/Department of Energy (AHAM/DOE) testing standards using several hydrofluoropropane-based zeotropic mixtures. The results are compared to baseline testing with R-134a and results obtained using the 750 Btu/h compressor. Hydrofluorocarbons R-245ca/R-152a performed comparably to R-134a. R-245ca/hydrocarbon R-270 (cyclopropane C{sub 3}H{sub 6}) outperformed all zeotropic mixtures and R-134a by at least 12.2 {+-} 0.7%. All refrigerants performed better using the larger compressor due to its inherently better efficiency. Refrigerant samples taken during refrigerator/freezer operation revealed substantial composition shifts (e.g., a 30% running composition shift of R-134a in the R-245ca/R-134a mixture). Sand et al. (1993) obtained an approximately 20% energy reduction using steady-state on-cycle energy consumption results; a comparison was made between chlorofluorocarbon R-12 and a hydrofluorocarbon R-32/hydrochlorofluorocarbon R-124 mixture. Lorenz and Meutzner (1975), originators of the Lorenz-Meutzner refrigerator/freezer design, state that the following parameters influence the optimum performance of the design: (1) heat exchanger size, (2) capillary tube length, (3) refrigerant charge, and (4) compressor size. This work investigates three of these parameters--capillary tube length, compressor size, and refrigerant charge.

Baskin, E.; Smith, N.D.; Delafield, F.R.; Tufts, M.W.

1999-07-01T23:59:59.000Z

36

Super Building Insulation by CO2 Foaming Process Research Project |  

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

Emerging Technologies » Super Building Insulation by CO2 Foaming Emerging Technologies » Super Building Insulation by CO2 Foaming Process Research Project Super Building Insulation by CO2 Foaming Process Research Project The Department of Energy is currently researching the development of building superinsulation through a carbon dioxide (CO2) foaming process. Project Description This project seeks to develop building super insulation through a carbon dioxide foaming process that does not use hydrofluorocarbons (HFCs), and which produces insulation with a high R-value. Project Partners Research is being undertaken between the Department of Energy and The Industrial Science & Technology Network. Project Goals The goal of this project is to develop advanced insulation without HFC, and to achieve a competitive processing cost for CO2 foaming technology.

37

EIA - Greenhouse Gas Emissions - High-GWP gases  

Gasoline and Diesel Fuel Update (EIA)

5. High-GWP gases 5. High-GWP gases 5.1. Total emissions Greenhouse gases with high global warming potential (high-GWP gases) are hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6), which together represented 3 percent of U.S. greenhouse gas emissions in 2009. Emissions estimates for the high-GWP gases are provided to EIA by the EPA's Office of Air and Radiation. The estimates for emissions of HFCs not related to industrial processes or electric transmission are derived from the EPA Vintaging Model. Emissions from manufacturing and utilities are derived by the EPA from a mix of public and proprietary data, including from the EPA's voluntary emission reduction partnership programs. For this year's EIA inventory, 2008 values for HFC-23 from HCFC-22

38

Energy and global warming impacts of next generation refrigeration and air conditioning technologies  

SciTech Connect (OSTI)

Significant developments have occurred in hydrofluorocarbon (HFC) and the application of ammonia and hydrocarbons as refrigerant working fluids since the original TEWI (Total Equivalent Warming Impact) report in 1991. System operating and performance data on alternative refrigerants and refrigeration technologies justify and updated evaluation of these new alternative refrigerants and competing technologies in well-characterized applications. Analytical and experimental results are used to show quantitative comparisons between HFCS, HFC blends, hydrocarbons, and ammonia, used as refrigerants. An objective evaluation is presented for commercial and near commercial non-CFC refrigerants/blowing agents and alternative refrigeration technologies. This information is needed for objective and quantitative decisions on policies addressing greenhouse gas emissions from refrigeration and air conditioning equipment. The evaluation assesses the energy use and global warming impacts of refrigeration and air conditioning technologies that could be commercialized during the phase out of HCFCS. Quantitative comparison TEWI for two application areas are presented. Opportunities for significant reductions in TEWI are seen with currently known refrigerants through improved maintenance and servicing practices and improved product designs.

Sand, J.R.; Fischer, S.K.; Baxter, V.D.

1996-10-01T23:59:59.000Z

39

Passive Two-Phase Cooling of Automotive Power Electronics: Preprint  

SciTech Connect (OSTI)

Experiments were conducted to evaluate the use of a passive two-phase cooling strategy as a means of cooling automotive power electronics. The proposed cooling approach utilizes an indirect cooling configuration to alleviate some reliability concerns and to allow the use of conventional power modules. An inverter-scale proof-of-concept cooling system was fabricated, and tests were conducted using the refrigerants hydrofluoroolefin HFO-1234yf and hydrofluorocarbon HFC-245fa. Results demonstrated that the system can dissipate at least 3.5 kW of heat with 250 cm3 of HFC-245fa. An advanced evaporator design that incorporates features to improve performance and reduce size was conceived. Simulation results indicate its thermal resistance can be 37% to 48% lower than automotive dual side cooled power modules. Tests were also conducted to measure the thermal performance of two air-cooled condensers--plain and rifled finned tube designs. The results combined with some analysis were then used to estimate the required condenser size per operating conditions and maximum allowable system (i.e., vapor and liquid) temperatures.

Moreno, G.; Jeffers, J. R.; Narumanchi, S.; Bennion, K.

2014-08-01T23:59:59.000Z

40

Buildings Energy Data Book: 7.1 National Legislation  

Buildings Energy Data Book [EERE]

5 5 Phase Out Schedule of Halocarbons in the U.S. (1) Gas % By % By Chlorofluorocarbons 75% 1994 75% 1994 (CFCs) 100% 1996 (4) 100% 1996 Bromofluorocarbons 100% 1994 (4) 100% 1994 (Halons) Hydrochlorofluorocarbons 35.0% 2004 35% 2003 (HCFCs) 75.0% 2010 75% 2010 90.0% 2015 90% 2015 99.5% 2020 99.5% 2020 100% 2030 (4) 100% 2030 Hydrofluorocarbons N.A. N.A. N.A. N.A. (HFCs) Note(s): Source(s): 1989 HCFC consumption + 2.8 % of 1989 CFC consumption 1996 N.A. N.A. 1) The phase out of halocarbons is consistent with Title VI of the Clean Air Act and is in accordance with the Montreal Protocol and Amendments. 2) The amount of gas produced and consumed in this year is established and defined as the base level. To meet basic domestic needs, levels of production are allowed to exceed the base level by up to 10%. 3) After this year, levels of production are no longer

Note: This page contains sample records for the topic "hydrochlorofluorocarbon hfc hydrofluorocarbon" 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
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41

Performance of a two-cycle refrigerator/freezer using HFC refrigerants  

SciTech Connect (OSTI)

A two-cycle 18 ft{sup 3} (0.51 m{sup 3}) refrigerator/freezer was tested utilizing American National Standards Institute/Association of Home Appliance Manufacturers (ANSI/AHAM) standards for energy consumption testing. A 34.9% energy consumption reduction was realized for a 1984 model refrigerator/freezer (1020 kWh original energy use). This paper presents a proven method of reducing the current Department of Energy (DOE) minimum energy-efficiency standards for refrigerator/freezers to the proposed year 2001 standards utilizing existing technology. For a top-mount, frost-free refrigerator/freezer having the above volume, the current DOE minimum energy standard is 770 kWh/year, and the proposed DOE year 2001 standard is 530 kWh/year (a 31% reduction). Therefore, some significant reductions may be obtained by implementing the modifications discussed in this paper into newer refrigerator/freezer models. The paper gives an overview of the modifications implemented by a Danish university on a US refrigerator/freezer and presents experimental performance testing results of the refrigerator/freezer. The modifications will cause the refrigerator/freezer to be more expensive, but the performance enhancements should offset cost. No cost analysis is presented in this paper, but a detailed cost analysis of a two-cycle refrigerator/freezer is contained in a 1993 US Environmental Protection Agency (EPA) report (EPA 1993). The refrigerator/freezer was tested using four refrigerants and compressors. Two compressors and refrigerants were tested in the freezer cycle, and four were tested in the fresh food cycle.

Baskin, E.; Delafield, F.R.

1999-07-01T23:59:59.000Z

42

Compatibility of lubricant additives with HFC refrigerants and synthetic lubricants. Final report, Part 1  

SciTech Connect (OSTI)

Part one of this research provides manufacturers of components of air-conditioning and refrigeration equipment with a useful list of lubricant additives, sources, functional properties and chemical species. The list in part one is comprised of domestic lubricant additive suppliers and the results of a literature search that was specifically targeted for additives reported to be useful in polyolester chemistry.

Cavestri, R.C. [Imagination Resources, Inc., Dublin, OH (United States)

1997-07-01T23:59:59.000Z

43

Elastohydrodynamic Lubrication with Polyolester Lubricants and HFC Refrigerants, Final Report, Volume 2  

SciTech Connect (OSTI)

Lubrication properties of refrigeration lubricants were investigated in high pressure nonconforming contacts under different conditions of temperature, rolling speed, and refrigerant concentration. The program was based upon the recognition that the lubrication regime in refrigeration compressors is generally elastohydrodynamic or hydrodynamic, as determined by the operating conditions of the compressor and the properties of the lubricant. Depending on the compressor design, elastohydrodynamic lubrication conditions exist in many rolling and sliding elements of refrigeration compressors such as roller element bearings, gears, and rotors. The formation of an elastohydrodynamic film separating rubbing surfaces is important in preventing the wear and failure of compressor elements. It is, therefore, important to predict the elastohydrodynamic (EHD) performance of lubricants under realistic tribocontact renditions. This is, however, difficult as the lubricant properties that control film formation are critically dependent upon pressure and shear, and cannot be evaluated using conventional laboratory instruments. In this study, the elastohydrodynamic behavior of refrigeration lubricants with and without the presence of refrigerants was investigated using the ultrathin film EHD interferometry technique. This technique enables very thin films, down to less than 5 nm, to be measured accurately within an EHD contact under realistic conditions of temperature, shear, and pressure. The technique was adapted to the study of lubricant refrigerant mixtures. Film thickness measurements were obtained on refrigeration lubricants as a function of speed, temperature, and refrigerant concentration. The effects of lubricant viscosity, temperature, rolling speed, and refrigerant concentration on EHD film formation were investigated. From the film thickness measurements, effective pressure-viscosity coefficients were calculated. The lubricants studied in this project included two naphthenic mineral oils (NMO), four polyolesters (POE), and two polyvinyl ether (PVE) fluids. These fluids represented viscosity grades of ISO 32 and ISO 68 and are shown in a table. Refrigerants studied included R-22, R-134a, and R-410A. Film thickness measurements were conducted at 23 C, 45 C, and 65 C with refrigerant concentrations ranging from zero to 60% by weight.

Gunsel, Selda; Pozebanchuk, Michael

1999-04-01T23:59:59.000Z

44

Experimental study of third (HFC) and fourth generation (HFO) refrigerants during flow boiling in singularities.  

E-Print Network [OSTI]

??La rduction de charge de fluides frigorignes dans les systmes de production de froid est un enjeu important s'inscrivant dans les politiques environnementales sur la (more)

Padilla Gomez, Miguel David

2011-01-01T23:59:59.000Z

45

Broadband Cable Access Networks: The HFC Plant, 3rd Ed edition  

Science Journals Connector (OSTI)

This book focuses on broadband distribution and systems architecture and concentrates on practical concepts that will allow the reader to do their own design, improvement, and troubleshooting work. The objective is to enhance the skill sets of a large ... Keywords: Data Transmission Systems, Networking

David Large; James Farmer

2008-10-01T23:59:59.000Z

46

Two-Phase Flow of Two HFC Refrigerant Mixtures Through Short Tube Orifices, Draft Final Report  

E-Print Network [OSTI]

The present study presents data for flow of two refrigerant mixtures through short tube orifices. The two mixtures were R3211251134a (23%/25%/52% on a mass percentage basis) and R321125 (50%/50%). The following presents results for the flow...

Payne, W. V.; O'Neal, D. L.

1994-01-01T23:59:59.000Z

47

The large contribution of projected HFC emissions to future climate forcing  

Science Journals Connector (OSTI)

...application, to the per capita con-sumption...virtually complete. Demand for refrigeration...households, persons per residence, GDP/capita, income distri-bution...as product and energy price. Middle...products implying a demand only for service...

Guus J. M. Velders; David W. Fahey; John S. Daniel; Mack McFarland; Stephen O. Andersen

2009-01-01T23:59:59.000Z

48

The large contribution of projected HFC emissions to future climate forcing  

Science Journals Connector (OSTI)

...Industrial non-energy, non-CO2 greenhouse...A Study of Household Income and Appliance...Environmental Energy Technologies...from China. Japan Air Conditioning...Energy Economics Japan, Energy Conservation...variations in total household energy requirements...

Guus J. M. Velders; David W. Fahey; John S. Daniel; Mack McFarland; Stephen O. Andersen

2009-01-01T23:59:59.000Z

49

Global warming impacts of ozone-safe refrigerants and refrigeration, heating, and air-conditioning technologies  

SciTech Connect (OSTI)

International agreements mandate the phase-out of many chlorine containing compounds that are used as the working fluid in refrigeration, air-conditioning, and heating equipment. Many of the chemical compounds that have been proposed, and are being used in place of the class of refrigerants eliminated by the Montreal Protocol are now being questioned because of their possible contributions to global warming. Natural refrigerants are put forth as inherently superior to manufactured refrigerants because they have very low or zero global warming potentials (GWPs). Questions are being raised about whether or not these manufactured refrigerants, primarily hydrofluorocarbons (HFCs), should be regulated and perhaps phased out in much the same manner as CFCs and HCFCs. Several of the major applications of refrigerants are examined in this paper and the results of an analysis of their contributions to greenhouse warming are presented. Supermarket refrigeration is shown to be an application where alternative technologies have the potential to reduce emissions of greenhouse gases (GHG) significantly with no clear advantage to either natural or HFC refrigerants. Mixed results are presented for automobile air conditioners with opportunities to reduce GHG emissions dependent on climate and comfort criteria. GHG emissions for hermetic and factory built systems (i.e. household refrigerators/freezers, unitary equipment, chillers) are shown to be dominated by energy use with much greater potential for reduction through efficiency improvements than by selection of refrigerant. The results for refrigerators also illustrate that hydrocarbon and carbon dioxide blown foam insulation have lower overall effects on GHG emissions than HFC blown foams at the cost of increased energy use.

Fischer, S.; Sand, J.; Baxter, V.

1997-12-01T23:59:59.000Z

50

California's new mandatory greenhouse gas reporting regulation  

SciTech Connect (OSTI)

Beginning in early 2009, approximately 1000 California businesses will begin reporting their greenhouse gas (GHG) emissions based on the requirements of a new regulation adopted by the California Air Resources Board (CARB) in December 2007. California's mandatory GHG reporting regulation is the first rule adopted as a requirement of the Global Warming Solutions Act of 2006, passed by the California Legislature as Assembly Bill 32 (AB 32; Nunez, Chapter 488, Statutes of 2006) and signed by Governor Arnold Schwarzenegger in September 2006. The regulation is the first of its kind in the United States to require facilities to report annual GHG emissions. In general, all facilities subject to reporting are required to report their on-site stationary source combustion emissions of CO{sub 2}, nitrous oxide (N{sub 2}O), and methane (CH{sub 4}). Some industrial sectors, such as cement producers and oil refineries, also must report their process emissions, which occur from chemical or other noncombustion activities. Fugitive emissions from facilities are required to be reported when specified in the regulation. Sulfur hexafluoride (SF{sub 6}) and hydrofluorocarbon (HFC) use is prevalent in electricity facilities and must be reported. CO{sub 2} emissions from biomass-derived fuels must be separately identified during reporting, and reporters must also provide their consumption of purchased or acquired electricity and thermal energy; these requirements will assist facilities in evaluating changes in their fossil fuel carbon footprints. 1 tab.

Patrick Gaffney; Doug Thompson; Richard Bode [California Air Resources Board, CA (United States)

2008-11-15T23:59:59.000Z

51

Heat transfer enhancement during condensation in smooth tubes with helical wire inserts .  

E-Print Network [OSTI]

??In the past two decades the refrigeration, air-conditioning and heat pump industries began the conversion from chlorofluorocarbon (CFC) refrigerants to hydrochlorofluorocarbons (HCFCs) and to natural (more)

Ji, Tianfu

2008-01-01T23:59:59.000Z

52

An Evaluation of the Environmental Impact of Different Commercial Supermarket Refrigeration Systems Using Low Global Warming Potential Refrigerants  

SciTech Connect (OSTI)

Commercial refrigeration systems consumed 1.21 Quads of primary energy in 2010 and are known to be a major source for refrigerant charge leakage into the environment. Thus, it is important to study the environmental impact of commercial supermarket refrigeration systems and improve their design to minimize any adverse impacts. The system s Life Cycle Climate Performance (LCCP) was presented as a comprehensive metric with the aim of calculating the equivalent mass of carbon dioxide released into the atmosphere throughout its lifetime, from construction to operation and destruction. In this paper, an open source tool for the evaluation of the LCCP of different air-conditioning and refrigeration systems is presented and used to compare the environmental impact of a typical multiplex direct expansion (DX) supermarket refrigeration systems based on three different refrigerants as follows: two hydrofluorocarbon (HFC) refrigerants (R-404A, and R-407F), and a low global warming potential (GWP) refrigerant (N-40). The comparison is performed in 8 US cities representing different climates. The hourly energy consumption of the refrigeration system, required for the calculation of the indirect emissions, is calculated using a widely used building energy modeling tool (EnergyPlus). A sensitivity analysis is performed to determine the impact of system charge and power plant emission factor on the LCCP results. Finally, we performed an uncertainty analysis to determine the uncertainty in total emissions for both R-404A and N-40 operated systems. We found that using low GWP refrigerants causes a considerable drop in the impact of uncertainty in the inputs related to direct emissions on the uncertainty of the total emissions of the system.

Beshr, Mohamed [University of Maryland, College Park; Aute, Vikrant [University of Maryland, College Park; Abdelaziz, Omar [ORNL; Fricke, Brian A [ORNL; Radermacher, Reinhard [University of Maryland, College Park

2014-01-01T23:59:59.000Z

53

Process development for the selective hydrogenolysis of CCl{sub 2}F{sub 2} (CFC-12) into CH{sub 2}F{sub 2} (HFC-32)  

SciTech Connect (OSTI)

A palladium on activated carbon catalyst is a suitable catalyst for the selective hydrogenolysis Of CCl{sub 2}F{sub 2} into CH{sub 2}F{sub 2}. Its stability is good: no deactivation occurred after 800 hours of operation. Even after addition of possible recycle components methane and CHClF{sub 2}, only minor deactivation was observed during 1600 hours of total operation. The catalyst performance and stability strongly depend on the hydrogen to CCl{sub 2}F{sub 2} feed ratio. A ratio of 6 leads to higher conversion, higher selectivity to CH{sub 2}F{sub 2} and higher stability. At low H{sub 2} to CCl{sub 2}F{sub 2} ratios the mechanism of deactivation is presumably coke deposition. However, the ratio cannot be raised too high because then sintering of the palladium particles causes deactivation. Addition of methane to the feed leads to additional deactivation, and, therefore, methane is only allowed in a recycle stream when high hydrogen to CCl{sub 2}F{sub 2} feed ratios are applied. Addition of CHClF{sub 2} to the feed does not lead to a higher CH{sub 2}F{sub 2} yield. The reaction pathway to CHClF{sub 2} and CH{sub 2}F{sub 2} is different from the route to methane. The selectivity to methane depends on the adsorption mode Of CCl{sub 2}F{sub 2} and is independent of both the CCl{sub 2}F{sub 2} and the hydrogen concentration. The ratio between CHClF{sub 2} and CH{sub 2}F{sub 2} is mainly determined by the CCl{sub 2}F{sub 2} concentration. A CFC-destruction process, which can destruct about 90% of the CFCs in use, based on this catalyst is both technically and economically feasible. The main features of this process are a liquid cooled, multi-tube fixed bed reactor, excess hydrogen, 100% CCl{sub 2}F{sub 2} conversion and a hydrogen recycle, in which methane is allowed.

Wiersma, A.; Makkee, M.; Moulijn, J.A. [Delft Univ. of Technology, Delft (Netherlands)] [and others

1996-12-31T23:59:59.000Z

54

Estimated 2017 Refrigerant Emissions of 2,3,3,3-tetrafluoropropene (HFC-1234yf) in the United States Resulting from Automobile Air Conditioning  

Science Journals Connector (OSTI)

The use of MAC systems also consumes significant quantities of fuel as compared to similar driving conditions without operating the air conditioning. ... However, turning off the air conditioner and rolling-down the windows also decreases fuel economy due to increased air drag but this scenario is not considered in these studies (1, 2). ... In 2006, the European Commission issued Directive 2006/40/EC (commonly known as the F-Gas Directive) (3), which requires new types of air-conditioned cars sold in the EU to have a refrigerant with a GWP of 150 or less starting in 2011, and all new vehicles to have a refrigerant with a GWP of 150 or less by 2017. ...

Stella Papasavva; Deborah J. Luecken; Robert L. Waterland; Kristen N. Taddonio; Stephen O. Andersen

2009-11-12T23:59:59.000Z

55

EIA-Voluntary Reporting of Greenhouse Gases Program - What are...  

U.S. Energy Information Administration (EIA) Indexed Site

gases such as hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride). The Greenhouse Effect Concentrations of several important greenhouse gases have increased by about 33...

56

Molecular Design Using Quantum Chemical Calculations for Property Estimation  

E-Print Network [OSTI]

techniques for molecular design. A simple hydrofluorocarbon refrigerant design example and a solvent design level information about any system can be predicted (e.g., molecular energies, electronic charge as the target property, motivated by an interest in chemically stable hydrofluorocarbon refrigerants. The second

Maranas, Costas

57

Mathematical modelling and thermodynamic optimization of a CO2 heat pump cycle.  

E-Print Network [OSTI]

??Due to the harmful environmental effects of HCFCs (hydrochlorofluorocarbons) and CFCs (chlorofluorocarbons) discovered in the late 20th century, interest has increased for more environmentally-friendly refrigerant (more)

Daley, Brendan

2012-01-01T23:59:59.000Z

58

EIA-Voluntary Reporting of Greenhouse Gases Program - Greenhouse Gases and  

U.S. Energy Information Administration (EIA) Indexed Site

Greenhouse Gases and Global Warming Potentials (GWP) Greenhouse Gases and Global Warming Potentials (GWP) Voluntary Reporting of Greenhouse Gases Program Greenhouse Gases and Global Warming Potentials (GWP) (From Appendix E of the instructions to Form EIA-1605) GREENHOUSE GAS NAME GREENHOUSE GAS CODE FORMULA GWP TAR1 AR42 (1) Carbon Dioxide CO2 CO2 1 1 (2) Methane CH4 CH4 23 25 (3) Nitrous Oxide N2O N2O 296 298 (4) Hydroflourocarbons HFC-23 (trifluoromethane) 15 CHF3 12000 14800 HFC-32 (difluoromethane) 16 CH2F2 550 675 HFC-41 (monofluoromethane) 43 CH3F 97 -3 HFC-125 (pentafluoroethane) 17 CHF2CF3 3400 3500 HFC-134 (1,1,2,2-tetrafluoroethane) 44 CHF2CHF2 1100 -3 HFC-134a (1,1,1,2-tetrafluoroethane) 18 CH2FCF3 1300 1430 HFC-143 (1,1,2-trifluorethane) 45 CHF2CH2F 330 -3 HFC-143a (1,1,1-trifluoroethane) 46 CF3CH3 4300 4470 HFC-152 (1,2-difluorethane) 47 CH2FCH2F

59

Design of Energy-Saving Algorithms for Hybrid Fiber Coaxial Networks Based on the DOCSIS 3.0 Standard  

Science Journals Connector (OSTI)

We propose energy-saving algorithms to improve the energy efficiency of hybrid fiber coaxial (HFC) networks that support DOCSIS (Data Over Cable Service ...

Zhu, Zuqing

2012-01-01T23:59:59.000Z

60

Emissions of Non-CO2 Greenhouse Gases From the Production and Use of Transportation Fuels and Electricity  

E-Print Network [OSTI]

286-290 (1989). T. J. Wallington, personal communication,12 and HFC-134a systems (Wallington, 1996). As a result ofis not detectable (Wallington, 1996). Thus, under today's

Delucchi, Mark

1997-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "hydrochlorofluorocarbon hfc hydrofluorocarbon" 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

Natural Refrigerant (R-729) Heat Pump  

Energy Savers [EERE]

Manufactured in the U.S. 2 Problem Statement * Current commercial and industrial heat pumps - Poor coefficient of performance (COP) at low temperatures * HFC refrigerant...

62

Characterization Studies of Materials and Devices used for Electrochemical Energy Storage  

E-Print Network [OSTI]

for Nafion in hydrogen fuel cell applications is that thebe used to fabricate hydrogen fuel cell (HFC) membranes withmembranes for hydrogen and methanol fuel cells. J Memb Sci

Membreno, Daniel Eduardo

2014-01-01T23:59:59.000Z

63

Estimating Policy-Driven Greenhouse Gas Emissions Trajectories in California: The California Greenhouse Gas Inventory Spreadsheet (GHGIS) Model  

E-Print Network [OSTI]

decision support tool for landfill gas-to energy projects,industrial emissions e. Landfills f. Solid waste treatmentreductions Forests, dairy, landfills 75% overall savings HFC

Greenblatt, Jeffery B.

2014-01-01T23:59:59.000Z

64

Synthesis and Characterization of Single Crystalline Hafnium Carbide Nanowires  

E-Print Network [OSTI]

transition metal carbide (TMC) nanowires has been reported, no HfC nanowires have been successfully syntheSynthesis and Characterization of Single Crystalline Hafnium Carbide Nanowires Jinshi Yuan,,§ Han carbide (HfC) is the most refractory compound known to mankind. A catalyst-assisted chemical vapor deposi

Qin, Lu-Chang

65

"GREENHOUSE GAS NAME","GREENHOUSE GAS CODE","FORMULA","GWP"  

U.S. Energy Information Administration (EIA) Indexed Site

Greenhouse Gases and Global Warming Potentials (GWP)" Greenhouse Gases and Global Warming Potentials (GWP)" "(From Appendix E of the instructions to Form EIA-1605)" "GREENHOUSE GAS NAME","GREENHOUSE GAS CODE","FORMULA","GWP" ,,,"TAR1","AR42" "(1) Carbon Dioxide","CO2","CO2",1,1 "(2) Methane","CH4","CH4",23,25 "(3) Nitrous Oxide","N2O","N2O",296,298 "(4) Hydroflourocarbons" "HFC-23 (trifluoromethane)",15,"CHF3",12000,14800 "HFC-32 (difluoromethane)",16,"CH2F2",550,675 "HFC-41 (monofluoromethane)",43,"CH3F",97,92 "HFC-125 (pentafluoroethane)",17,"CHF2CF3",3400,3500

66

DE-FE0012829 | netl.doe.gov  

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

of two months and gather data necessary for further process scale-up. In this process, CO2-containing flue gas passes through one side of the PEEK HFC, while a CO2 selective...

67

Chapter 10: Biological Impacts of ClimateChange 1.Nature of Climate Change  

E-Print Network [OSTI]

enters the atmosphere through the burning of fossil fuels (oil, natural gas, and coal), solid waste and by the decay of organic waste in municipal solid waste landfills. · Nitrous Oxide (N2O): Nitrous oxide and solid waste. · Fluorinated Gases: Hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride

Gottgens, Hans

68

Honeywell developing low-GWP liquid blowing agent for foam insulation  

Science Journals Connector (OSTI)

Honeywell reports that it is developing a new blowing agent with low global warming potential (GWP) for energy-efficient polyurethane foam insulation. The non-flammable liquid blowing agent will provide customers with an alternative to hydrocarbons and traditional hydrofluorocarbons (HFCs) and assist customers in reducing the overall environmental impact of foam, the company says.

2009-01-01T23:59:59.000Z

69

Environmental Data Sheet ENVIRONMENTAL DATA SHEET Dell Inc.  

E-Print Network [OSTI]

, the customer should not rely upon this information in making decisions about electrical tolerances or otherwise) other than in cables and interconnect parts · CFCs (chlorofluorocarbons), HCFCs (hydrofluorocarbons in the Montreal Protocol annex A, B, or C is used in Dell's manufacturing plants. Additional Materials Information

Fiebig, Peter

70

Peter Bernath Department of Chemistry, University of YorkDepartment of Chemistry, University of York  

E-Print Network [OSTI]

- 12 11,000 CFC - 113 6,540 Carbon Tetrachloride 2,700 HCFC-142b, CCl4, CH3Cl, CF4, SF6, (HFC-134a), Carbon Tetrachloride 2,700 HCFC - 22 5,160 HCFC - 141b 2,250 (HFC-134a), F2CO, ClFCO, Cl2CO, HCl, HF Abad, et al., Ethane, ethyne and carbon monoxide concentrations in the upper troposphere and lower

71

Final Rule for Nuclear Safety Management (10 CFR Part 830)  

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

717 717 Federal Register / Vol. 66, No. 74 / Tuesday, April 17, 2001 / Rules and Regulations engineering and cost analyses because the results showed that the two blowing agent alternatives can be used to achieve similar performance for similar costs to HFC-245fa. DOE estimates are reasonable and address the concern of the Department of Justice to provide more than one choice of insulation blowing agent with comparable performance and at approximately the same cost. Based on the analysis of the three different types of blowing agents, HFC- 245fa-, pentane/cyclopentane- and HFC-134a, DOE concluded that water heater manufacturers will have several choices to reach the standard, including blends of these blowing agents, and therefore, will not have to rely on a sole source supplier.

72

Atmos. Chem. Phys., 12, 1018110193, 2012 www.atmos-chem-phys.net/12/10181/2012/  

E-Print Network [OSTI]

.77 ppt for HFC-152a, 79.1 ppt for CF4, 4.22 ppt for PFC-116, and 0.56 ppt for PFC-218. The background for HFC-152a, 2.4 ± 2.1 kt yr-1 for CF4, 0.27 ± 0.26 kt yr-1 for PFC-116, and 0.061 ± 0.095 kt yr-1., 2010; Montzka et al., 2010; Oram et al., 1998). PFCs are emit- ted from aluminum smelters (CF4, PFC-116

Meskhidze, Nicholas

73

Affiliated with Universit de Montral Pavillons lassonde,  

E-Print Network [OSTI]

-use in the sanitation system, we use 92% less drinking water than conventional buildings. #12;. Red : magma orange : earth Green : flora Blue : Sky eneRGY PeRFoRManCe 60 % better than the standard set by model national energy code of canada for buildings. mechanical systems that use hfc-134a

74

Accelerated screening methods for determining chemical and thermal stability of refrigerant-lubricant mixtures part II: Experimental comparisons and verification of methods. Quarterly technical progress report, October 1, 1993--March 31, 1994  

SciTech Connect (OSTI)

The research reported herein continued to concentrate on in situ conductivity measurements for development into an accelerated screening method for determining the chemical and thermal stabilities of refrigerant/lubricant mixtures. The work reported herein was performed in two phases. In the first phase, sealed tubes were prepared with steel catalysts and mixtures of CFC-12, HCFC-22, HFC-134a, and HFC-32/HFC-134a (zeotrope 30:70) refrigerants with oils as described in ANSI/ASHRAE Method 97-1989. In the second phase of work, modified sealed tubes, with and without steel catalysts present, were used to perform in situ conductivity measurements on mixtures of CFC-12 refrigerant with oils. The isothermal in situ conductivity measurements were compared with conventional tests, e.g., color measurements, gas chromatography, and trace metals to evaluate the capabilities of in situ conductivity for determining the chemical and thermal stabilities of refrigerant/lubricant mixtures. Other sets of tests were performed using ramped temperature conditions from 175{degrees}C (347{degrees}F) to 205{degrees}C (401{degrees}F) to evaluate the capabilities of in situ conductivity for detecting the onset of rapid degradation in CFC-12, HCFC-22 and HFC-134a refrigerant mixtures with naphthenic oil aged with and without steel catalysts present.

Kauffman, R. [Dayton Univ., OH (United States). Research Inst.

1994-07-01T23:59:59.000Z

75

Decomposition of fluorohydrocarbons in atmospheric-pressure flowing air using coaxial-line-based microwave torch plasma  

Science Journals Connector (OSTI)

Results of the investigation of decomposition of fluorohydrocarbons C2H2F4 (HFC-134a) and CHClF2 (CFC-22) in atmospheric-pressure flowing air using a coaxial-line-based microwave torch plasma are presented. Conce...

M. Jasi?ski; P. Szczucki; M. Dors; J. Mizeraczyk

2000-03-01T23:59:59.000Z

76

Reliability of Heat Pumps Containing R410-A Refrigerant  

E-Print Network [OSTI]

Ester (POE) oils used with HFC refrigerants will break down into acid and alcohol when exposed to heat. Manufacturers have many tools to establish reliability of a product prior to mass production. Units and compressors can be nm on life tests. Prototype...

McJimsey, B. A.; Cawley, D.

1998-01-01T23:59:59.000Z

77

Alternative Refrigerants for Building Air Conditioning  

E-Print Network [OSTI]

The majority of building air conditioning has traditionally been achieved with vapor compression technology using CFC-I I or HCFC-22 as refrigerant fluids. CFC-11 is being successfully replaced by HCFC-123 (retrofit or new equipment) or by HFC- 134a...

Bivens, D. B.

1996-01-01T23:59:59.000Z

78

Heliostat Stimulator operator's manual  

SciTech Connect (OSTI)

The Heliostat Stimulator is a portable test tool, housed in a suitcase, which can be used to perform the following functions: (1) acceptance testing of newly manufactured Heliostat Controllers (HC) and Heliostat Field Controllers (HFC); (2) aid in the installation and alignment of Heliostats; and (3) provide diagnostic troubleshooting capability in the event of Heliostat failure in the field.

Not Available

1980-11-01T23:59:59.000Z

79

Empirical correlations for the modeling of R-134a flow through adiabatic capillary tubes  

SciTech Connect (OSTI)

This paper presents the results of an experimental study on capillary tubes commonly used as an expansion device in household refrigerators and freezers. The experiments were performed with the hydrofluorocarbon R-134a at different condensing pressures and levels of subcooling. The pressure and temperature profiles along the capillary tubes were measured in each test run. The data set was then used to evaluate the suitability of some equations previously reported in the literature for the single-phase friction factor, the underpressure of vaporization, and the entrance contraction loss factor. Correlations for the average and local two-phase friction factors were also developed based on the measured data.

Melo, C.; Neto, C.B.; Silva Ferreira, R.T. da

1999-07-01T23:59:59.000Z

80

Aging of Polyurethane Foam Insulation in Simulated Refrigerator Panels--Three-Year Results with Third-Generation Blowing Agents  

SciTech Connect (OSTI)

Laboratory data are presented on the effect of constant-temperature aging on the apparent thermal conductivity of polyurethane foam insulation for refrigerators and freezers. The foam specimens were blown with HCFC-141b and with three of its potential replacements--HFC-134a, HFC-245fa, and cyclopentane. Specimens were aged at constant temperatures of 90 F, 40 F, and -10 F. Thermal conductivity measurements were made on two types of specimens: full-thickness simulated refrigerator panels containing foam enclosed between solid plastic sheets, and thin slices of core foam cut from similar panels. Results are presented for the first three years of a multi-year aging study. Preliminary comparisons of measured data with predictions of a mathematical aging model are presented.

Wilkes, K.E.

2001-05-29T23:59:59.000Z

Note: This page contains sample records for the topic "hydrochlorofluorocarbon hfc hydrofluorocarbon" 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

Aging of polyurethane foam insulation in simulated refrigerator panels -- Initial results with third-generation blowing agents  

SciTech Connect (OSTI)

Laboratory data are presented on the effect of constant-temperature aging on the apparent thermal conductivity of polyurethane foam insulation for refrigerators and freezers. The foam specimens were blown with HCFC-141b and with three of its potential replacements -- HFC-134a, HFC-245fa, and cyclopentane. Specimens were aged at constant temperatures of 90 F, 40 F, and {minus}10 F. Thermal conductivity measurements were made on two types of specimens: full-thickness simulated refrigerator panels containing foam enclosed between solid plastic sheets, and thin slices of core foam cut from similar panels. Results are presented for about 250 days of aging for the core-foam specimens and for the first six months of aging for the full-thickness panels.

Wilkes, K.E.; Gabbard, W.A.; Weaver, F.J.

1998-11-01T23:59:59.000Z

82

Aging of Polyurethane Foam Insulation in Simulated Refrigerator Panels--Two-Year Results with Third-Generation Blowing Agents  

SciTech Connect (OSTI)

Laboratory data are presented on the effect of constant-temperature aging on the apparent thermal conductivity of polyurethane foam insulation for refrigerators and freezers. The foam specimens were blown with HCFC-141b and with three of its potential replacements--HFC-134a, HFC-245fa, and cyclopentane. Specimens were aged at constant temperatures of 90 F, 40 F, and {minus}10 F. Thermal conductivity measurements were made on two types of specimens: full-thickness simulated refrigerator panels containing foam enclosed between solid plastic sheets, and thin slices of core foam cut from similar panels. Results are presented for the first two years of a multi-year aging study. Preliminary comparisons of measured data with predictions of a mathematical aging model are presented.

Wilkes, K.E.

2001-02-14T23:59:59.000Z

83

Aging of Polyurethane Foam Insulation in Simulated Refrigerator Panels--One-Year Results with Third-Generation Blowing Agents  

SciTech Connect (OSTI)

Laboratory data are presented on the effect of constant-temperature aging on the apparent thermal conductivity of polyurethane foam insulation for refrigerators and freezers. The foam specimens were blown with HCFC-141b and with three of its potential replacements--HFC-134a, HFC-245fa, and cyclopentane. Specimens were aged at constant temperatures of 90 F, 40 F, and {minus}10 F. Thermal conductivity measurements were made on two types of specimens: full-thickness simulated refrigerator panels containing foam enclosed between solid plastic sheets, and thin slices of core foam cut from similar panels. Results are presented for the first year of a multi-year study for the full-thickness panels and for about 1-1/2 years of aging for the core-foam specimens.

Gabbard, W.A.; Weaver, F.J.; Wilkes, K.E.

1999-09-27T23:59:59.000Z

84

Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants  

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

Thermodynamic Evaluation of Thermodynamic Evaluation of Low-GWP Refrigerants Mark O. McLinden National Institute of Standards and Technology markm@boulder.nist.gov; 303-497-3580 April 3, 2013 Optimization Fluid Modeling Cycle Modeling Final Candidates Optimum Thermo Parameters 2 | Building Technologies Office eere.energy.gov Purpose & Objectives Problem Statement: HFC refrigerants face restrictions: U.S./Canada/Mexico proposal to Montreal Protocol (85 % cut) EU regulations likely on all application areas (79 % cut)

85

Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants  

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

Thermodynamic Evaluation of Thermodynamic Evaluation of Low-GWP Refrigerants Mark O. McLinden National Institute of Standards and Technology markm@boulder.nist.gov; 303-497-3580 April 3, 2013 Optimization Fluid Modeling Cycle Modeling Final Candidates Optimum Thermo Parameters 2 | Building Technologies Office eere.energy.gov Purpose & Objectives Problem Statement: HFC refrigerants face restrictions: U.S./Canada/Mexico proposal to Montreal Protocol (85 % cut) EU regulations likely on all application areas (79 % cut)

86

Low GWP Working Fluid for High Temperature Heat Pumps  

E-Print Network [OSTI]

Low GWP Working Fluid for High Temperature Heat Pumps: DR-2 Chemical Stability at High Temperatures Temp Heat Pumps: DR-2 Very Low GWP AND Non-Flammable HFC-245fa DR-2 Chemical Formula CF3CH2CHF2 HFO 171.3 Pcr [MPa] 3.65 2.9 Kontomaris-DuPont; European Heat Pump Summit, Nuremberg, October 15th, 2013

Oak Ridge National Laboratory

87

May 13, 1998 Gas Frac. Mol.Wt. Density Speci c Ht. Boil. Pt.  

E-Print Network [OSTI]

. Automatic switch from empty to full bottles DataLink ethernet 4 #12;Gas Mixing Station Four independent gas.Rate Normal Rate Station of Gas SCCM SCCM SCCM Barrel HFC-134a 0.32 10,000 3,200 1,240 Inner Ar 1.37 5,000 6K.Abe Gas System May 13, 1998 RPC Gas Gas Frac. Mol.Wt. Density Speci c Ht. Boil. Pt. g=l cal=g c c

Llope, William J.

88

Lubricant return comparison of naphthenic and polyol ester oils in R-134a household refrigeration applications  

SciTech Connect (OSTI)

This paper presents mineral oils and polyol esters as possible lubricant options for domestic refrigeration applications employing R-134a as the heat exchange fluid. A performance comparison, based on data presented, is made between the mineral oils and polyol esters evaluated. To more closely examine lubricant return with N-70 and R-134a and ensure that the oil is not contributing to any deterioration in efficiency due to its accumulation in evaporators, a special test unit was designed with a difficult oil return configuration and its performance carefully monitored. Oil return with a hydrofluorocarbon-miscible polyol ester, R-133-O was also evaluated in this setup and its performance results compared to those obtained with the naphthenic refrigeration oil.

Reyes-Gavilan, J.L.; Flak, G.T.; Tritcak, T.R. [Witco Corp., Oakland, NJ (United States)

1996-12-31T23:59:59.000Z

89

Synopsis of residential refrigerator/freezer alternative refrigerants evaluation  

SciTech Connect (OSTI)

The experimental testing on residential refrigerator/freezers (R/Fs) is summarized in this paper. R/F testing focused on two areas: alternative refrigerants and equipment configurations. The refrigerants evaluated consisted of single components, azeotropes, and zeotropes derived from hydrofluorocarbons (HFCs) and hydrocarbons (HCs). These refrigerants were evaluated in conventional and unconventional R/F designs. Major and minor design modifications were studied. Minor modifications consisted of various capillary tube lengths, door insulations, and compressors, while major modifications included two-evaporator and two-cycle R/F systems. Results obtained from testing the two-cycle system will be discussed in a later paper. This paper presents the experimental results of alternative technologies evaluated as replacements for ozone depleting chemicals.

Baskin, E. [Environmental Protection Agency, Research Triangle Park, NC (United States)

1998-12-31T23:59:59.000Z

90

Word Pro - S12  

U.S. Energy Information Administration (EIA) Indexed Site

Note 1. Emissions of Carbon Dioxide and Other Green- Note 1. Emissions of Carbon Dioxide and Other Green- house Gases. Greenhouse gases are those gases-such as water vapor, carbon dioxide (CO 2 ), methane, nitrous oxide, hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride-that are transparent to solar (short- wave) radiation but opaque to long-wave (infrared) radiation, thus preventing long-wave radiant energy from leaving Earth's atmosphere. The net effect is a trapping of absorbed radiation and a tendency to warm the planet's surface. Energy-related carbon dioxide emissions account for about 98 percent of U.S. CO 2 emissions. The vast majority of CO 2 emissions come from fossil fuel combustion, with smaller amounts from the nonfuel use of fossil fuels, as well as from electricity generation using geothermal energy and non-

91

Supermarket with Ground Coupled Carbon Dioxide Refrigeration Plant  

E-Print Network [OSTI]

refrigeration remains the last big subsector and the strongest emission source of the fluorinated hydrocarbons (HFC) in Germany? - Kauffeld [4] About 65 % of the cooling needs in Germany for frozen and refrigerated food products ? over 50.000 GWh.../a [2] In 2011, 72.4 % of the sales share of food retail industry realized in discounters and supermarkets in Germany [1] Supermarket: ? 600 ? 2.000 kWh/m2.a (PE) [3] Normal building: 200 ? 400 kWh/m2.a (PE) [4] [1] EHI retail institute 2012...

Rehault, N.

2012-01-01T23:59:59.000Z

92

The Remarkable Environmental Rebound Effect of Electric Cars: A Microeconomic Approach  

Science Journals Connector (OSTI)

For FBE and HFC cars, the high capital costs cause a noteworthy decrease in environmental pressures for some indicators (negative rebound effect). ... For instance, there are approaches based on Engel curves (expenditure elasticities)(24, 25) or on the shifting of expenditure patterns between income groups. ... When the environmental profile of the product of investigation is very different from that in other sectors, rebound effects from a reallocation of expenditures can be very high, as was the case for FEP and TETP for FBE cars. ...

David Font Vivanco; Jaume Freire-Gonzlez; Ren Kemp; Ester van der Voet

2014-09-26T23:59:59.000Z

93

Modelica-based modelling and simulation of dry-expansion shell-and-tube evaporators working with alternative refrigerant mixtures  

Science Journals Connector (OSTI)

A new methodology of intermediate complexity level is developed to model the dry-expansion shell and U-tube evaporators. The model has a reasonable level of accuracy and uses fundamental physical principles in a distributed parameters approach capable of detecting the complex circuit of the shell-side flow. This level of details is necessary to simulate accurately the zeotropic refrigerant mixtures evaporation. Using Modelica language gives a heat exchanger model with a generic flow arrangement. The model is experimentally validated using a standard shell-and-tube evaporator working with HFC-134a. Three distinct working fluids, pure HFC-134a, R-407C, and a specially selected glide matching refrigerant mixture are simulated in the same heat source duty with different shell-and-tube configurations. Three different gas superheat values are also taken into account. The total amount of irreversibility is considered by calculating the total exergy losses. It is concluded that the effect of the temperature profile of any refrigerant mixture can be substantial on the relative performance of a particular heat exchanger configuration compared to counter-flow configuration.

Khattar Assaf; Assaad Zoughaib; Denis Clodic

2011-01-01T23:59:59.000Z

94

Aging of polyurethane insulation foamed with second- and third-generation blowing agents  

SciTech Connect (OSTI)

Results are presented on two studies of the effect of aging on the apparent thermal conductivity of polyurethane foam insulation for refrigerators. Both studies are cooperative projects between the Oak Ridge National Laboratory and the Appliance Research Consortium. The first study has been ongoing for four years and involves evaluation of second generation blowing agents: HCFC-141b and HCFC-142/22 blend with CFC-11 for comparison. The second study has recently started and involves third generation blowing agents: HFC-134a, HFC-245fa. and cyclopentane with HCFC-141b for comparison. Both studies consist of periodic thermal measurements on panels made with solid steel and/or plastic skins and a core of foam to simulate refrigerator walls, and measurements on thin slices with cut faces to characterize the core foam. Laboratory data are presented on four years of aging of panels containing second generation blowing agents. Preliminary data are presented for the third generation blowing agents. The data on panels are compared with predictions of computer models of foam aging.

Wilkes, K.E.; Gabbard, W.A.; Weaver, F.J.

1998-05-01T23:59:59.000Z

95

Thermodynamic Prediction of Compositional Phases Confirmed by Transmission Electron Microscopy on Tantalum-Based Alloy Weldments  

SciTech Connect (OSTI)

Tantalum alloys have been used by the U.S. Department of Energy as structural alloys for radioisotope based thermal to electrical power systems since the 1960s. Tantalum alloys are attractive for high temperature structural applications due to their high melting point, excellent formability, good thermal conductivity, good ductility (even at low temperatures), corrosion resistance, and weldability. Tantalum alloys have demonstrated sufficient high-temperature toughness to survive prolonged exposure to the radioisotope power-system working environment. Typically, the fabrication of power systems requires the welding of various components including the structural members made of tantalum alloys. Issues such as thermodynamics, lattice structure, weld pool dynamics, material purity and contamination, and welding atmosphere purity all potentially confound the understanding of the differences between the weldment properties of the different tantalum-based alloys. The objective of this paper is to outline the thermodynamically favorable material phases in tantalum alloys, with and without small amounts of hafnium, during and following solidification, based on the results derived from the FactSage(c) Integrated Thermodynamic Databank. In addition, Transition Electron Microscopy (TEM) data will show for the first time, the changes occurring in the HfC before and after welding, and the data will elucidate the role HfC plays in pinning grain boundaries.

Moddeman, William E.; Birkbeck, Janine C. [BWXT Pantex, Amarillo, Texas 79120-0020 (United States); Barklay, Chadwick D.; Kramer, Daniel P. [University of Dayton Research Institute, Dayton OH 45469-0102 (United States); Miller, Roger G.; Allard, Lawrence F. [Oak Ridge National Laboratory, Oak Ridge, TN 37831-6064 (United States)

2007-01-30T23:59:59.000Z

96

The design of a cathode to operate in an oxygen-rich environment  

SciTech Connect (OSTI)

The primary problem with Hall plasma accelerator operation on oxygen is poor cathode performance and short lifetime. The primary problem with micro Hall thrusters is the absence of a stable low power cathode. Cathodes traditionally used for both applications employ thermionic emitters which are not efficient and which are easily oxidized in an oxygen-rich environment. The field emitter cathode presented in this report has the potential of filling both vacancies since it does not require a high-power heater and can be scaled down with the size of the thruster. The advantages to using Hf and HfC as emitting materials are low work functions and high resistance to oxygen poisoning. Preliminary investigations proved that HfC emitters can operate in 7.6 mTorr oxygen pressure environments. The initial cathode design employs an electrostatic lens that also acts as an ion filter to prevent thruster ions from bombarding the field emitters while decelerating the electron beam and keeping it focused to ensure efficient performance. Electron trajectories through the cathode and ion filtering capabilities are presented in this report as predicted by the charged particle code, MAGIC.

Marrese, Colleen M.; Gallimore, Alec D.; Mackie, William A.; Evans, David E. [Plasmadynamic and Electric Propulsion Lab., University of Michigan Dept. of Aerospace Engineering FXB Building, 1320 Beal Ann Arbor, Michigan 48109-2118 (United States); Linfield Research Institute 900 Baker St. McMinnville, Oregon 97128-6894 (United States)

1997-01-10T23:59:59.000Z

97

NREL: Vehicle Ancillary Loads Reduction - Air Conditioning and Emissions  

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

Conditioning and Emissions Conditioning and Emissions Air conditioning and indirect emissions go together in the sense that when a vehicle's air conditioning system is in use, fuel economy declines. When more petroleum fuel is burned, more pollution and greenhouse gases are emitted. An additional, "direct" source of greenhouse gas emissions is the refrigerant used in air conditioning. Called HFC-134a, this pressurized gas tends to seep through tiny openings and escapes into the atmosphere. It can also escape during routine service procedures such as system recharging. NREL's Vehicle Ancillary Loads Reduction team applied its vehicle systems modeling expertise in a study to predict fuel consumption and indirect emissions resulting from the use of vehicle air conditioning. The analysis

98

Building Energy Software Tools Directory: Heat Pump Design Model  

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

Heat Pump Design Model Heat Pump Design Model Heat Pump Design Model logo. Research tool for use in the steady-state simulation and design analysis of air-to-air heat pumps and air conditioners. The program can be used with most of the newer HFC refrigerants as well as with HCFCs and CFCs. The standard vapor-compression cycle is modeled with empirical representations for compressor performance and first-principle region-by-region modeling of the heat exchangers. An online Web version is available that can be used with default configurations or with user-specified component and operating parameters for analyzing the performance of single-speed, air-to-air equipment. User configurations can be saved for later use. Parametric analyses can be made and performance trends plotted online.

99

High-Frequency Coherent Edge Fluctuations in a High-Pedestal-Pressure Quiescent H-Mode Plasma  

Science Journals Connector (OSTI)

A set of high frequency coherent (HFC) modes (f=80250??kHz) is observed with beam emission spectroscopy measurements of density fluctuations in the pedestal of a strongly shaped quiescent H-mode plasma on DIII-D, with characteristics predicted for kinetic ballooning modes (KBM): propagation in the ion-diamagnetic drift direction; a frequency near 0.20.3 times the ion-diamagnetic frequency; inferred toroidal mode numbers of n?1025; poloidal wave numbers of k??0.170.4??cm-1; and high measured decorrelation rates (?c-1??s?0.5106??s-1). Their appearance correlates with saturation of the pedestal pressure.

Z. Yan; G. R. McKee; R. J. Groebner; P. B. Snyder; T. H. Osborne; K. H. Burrell

2011-07-29T23:59:59.000Z

100

Relationship between the merit factor of thermoelectric materials and the air conditioning unit of urban electric cars  

SciTech Connect (OSTI)

The main benefit of electric cars is to reduce air pollution in cities that is thus desirable to equip them with non polluting air conditioning units and this rules out frigorific compressors operating with CFC. The planned replacement of CFC by HFC is at best an interim solution. The best solution is certainly to use thermoelectric air conditioning units, which are inherently pollution-free. However, these have a fairly low COPF when compared to traditional compressor units. We study the relationship between the cooling of the interior of urban electric cars and the merit factor of the thermoelectric material in their Peltier unit. This should help provide concrete target properties of future T E materials. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

Buffet, J. [Counsulting Engineer, 2 av. DODE de la BRUNERIE 75016 Paris (France)

1994-08-10T23:59:59.000Z

Note: This page contains sample records for the topic "hydrochlorofluorocarbon hfc hydrofluorocarbon" 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

News From the D.C. Office: Integrated Chiller Retrofits-Sharing Experience  

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

3 Aerial view of Washington D.C. 3 Aerial view of Washington D.C. News From the D.C. Office Integrated Chiller Retrofits: Sharing Experience Makes "Cool Sense" A recent issue of the Center for Building Science News [Spring 1996, p.2] described the opportunities for significant energy savings from replacing older, inefficient chillers. These savings can be increased greatly if building owners and managers approach the chiller replacement not just as a requirement, but also as an opportunity-that of investing in other energy-saving measures that reduce cooling loads and lead to the downsizing of the chiller and related equipment. The Air-Conditioning and Refrigeration Institute estimates that 80,000 existing chillers using CFC refrigerants need to be replaced or converted to use HCFC or HFC refrigerants. Of these, about 20,000 will be replaced or

102

Climate Change 2001: The Scientific Basis  

Office of Scientific and Technical Information (OSTI)

Climate Change 2001: Climate Change 2001: Working Group I: The Scientific Basis Get Javascript Other reports in this collection 4. Atmospheric Chemistry and Greenhouse Gases Contents Executive Summary 4.1 Introduction 4.1.1 Sources of Greenhouse Gases 4.1.2 Atmospheric Chemistry and Feedbacks 4.1.3 Trace Gas Budgets and Trends 4.1.4 Atmospheric Lifetimes and Time-Scales 4.2 Trace Gases: Current Observations, Trends and Budgets 4.2.1 Non-CO2 Kyoto Gases 4.2.1.1 Methane (CH4) 4.2.1.2 Nitrous oxide (N2O) 4.2.1.3 Hydrofluorocarbons (HFCs) 4.2.1.4 Perfluorocarbons (PFCs) and sulphur hexafluoride (SF6) 4.2.2 Montreal Protocol Gases and Stratospheric Ozone (O3) 4.2.3 Reactive Gases 4.2.3.1 Carbon monoxide (CO) and hydrogen (H2) 4.2.3.2 Volatile organic compounds (VOC) 4.2.3.3 Nitrogen oxides (NOx)

103

Demonstration of high efficiency elastocaloric cooling with large ?T using NiTi wires  

Science Journals Connector (OSTI)

Vapor compression (VC) is by far the most dominant technology for meeting all cooling and refrigeration needs around the world. It is a mature technology with the efficiency of modern compressors approaching the theoretical limit but its environmental footprint remains a global problem. VC refrigerants such as hydrochloroflurocarbons (HCFCs) and hydrofluorocarbons (HFCs) are a significant source of green house gas emissions and their global warming potential (GWP) is as high as 1000 times that of CO2 [Buildings Energy Data Book (Building Technologies Program Department of Energy 2009)]. There is an urgent need to develop an alternative high-efficiency cooling technology that is affordable and environmentally friendly [A. D. Little Report For Office of Building Technology State and Community Programs Department of Energy 2001]. Here we demonstrate that elastocaloric cooling (EC) a type of solid-state cooling mechanism based on the latent heat of reversible martensitic transformation can have the coefficient of performance as high as ?11 with a directly measured ?T of 17?C. The solid-state refrigerant of EC completely eliminates the use of any GWP refrigerants including HCFCs/HFCs.

Jun Cui; Yiming Wu; Jan Muehlbauer; Yunho Hwang; Reinhard Radermacher; Sean Fackler; Manfred Wuttig; Ichiro Takeuchi

2012-01-01T23:59:59.000Z

104

The Impact of Blowing Agents on Residential Water Heater Performance  

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

The Impact of Blowing Agents on Residential Water Heater Performance The Impact of Blowing Agents on Residential Water Heater Performance Title The Impact of Blowing Agents on Residential Water Heater Performance Publication Type Report LBNL Report Number LBNL-47352 Year of Publication 2001 Authors Lekov, Alexander B., James D. Lutz, Camilla Dunham Whitehead, and James E. McMahon Document Number LBNL-47352 Date Published January 12 Abstract The National Appliance Energy Conservation Act of 1987 (NAECA) requires the U.S. Department of Energy (DOE) to consider amendments to the energy conservation standards to increase energy efficiency in residential water heaters. A driving force affecting efficiency is the ozone-depletion regulation regarding blowing agents for insulation in all water heater fuel types. This paper presents results of cost and efficiency impacts of three potential blowing agents. Residential water heaters are typically insulated with polyurethane foam in the space between the tank and the jacket. Currently, water heater manufacturers use HCFC-141b, an ozone-depleting substance, as a blowing agent. After 2003, as a result of the Montreal Protocol (1993), manufacturers must use blowing agents that do not deplete the ozone layer. The analysis presented in this paper considers three replacement candidates, HFC-245fa, HFC-134a, and cyclopentane by comparing their efficiency and cost effectiveness when applied to water heater insulation. This analysis used computer simulation models and other analytical methods to investigate the efficiency improvements due to different design options, when alternative blowing agents are applied. The calculations were based on the DOE test procedure for residential water heaters. The analysis used average manufacturer, retailer, and installer costs to calculate the total consumer costs. Consumer operating expenses were calculated based on modeled energy consumption under test procedure conditions and U.S. average energy prices. With this information, a cost-efficiency relationship was developed to show the average manufacturer and consumer cost to achieve increased efficiency.

105

Laboratory test results on the thermal resistance of polyisocyanurate foamboard insulation blown with CFC-11 substitutes: A cooperative industry/government project  

SciTech Connect (OSTI)

The fully halogenated chlorofluorocarbon gases (CFC-11 and CFC-12) are used as blowing agents for foam insulations for building and appliance applications. The thermal resistance per unit thickness of these insulations is greater than that of other commercially available insulations. Mandated reductions in the production of these chemicals may lead to less efficient substitutes and increase US energy consumption by one quad or more. This report describes laboratory thermal and aging tests on a set of industry-produced, experimental polyisocyanurate (PIR) laminate boardstock to evaluate the viability of hydrochlorofluorocarbons (HCFSs) as alternative blowing agents to chlorofluorcarbon-11 (CFC-11). The PIR boards were blown with five gases: CFC-11, HCFC- 123, HCFC-141b, and 50/50 and 65/35 blends of HCFC-123/HCFC-141b. These HCFC gases have a lower ozone depletion potential than CFC-11 or CFC-12. Apparent thermal conductivity (k) was determined from 0 to 50{degrees}C. Results on the laminate boards provide an independent laboratory check on the increase in k observed for field exposure in the Roof Thermal Research Apparatus (RTRA). The measured laboratory increase in k was between 8 and 11% after a 240-d field exposure in the RTRA. Results are reported on a thin-specimen, aging procedure to establish the long-term thermal resistance of gas-filled foams. These thin specimens were planed from the industry-produced boardstock foams and aged at 75 and 150{degrees}F for up to 300 d. The resulting k-values were correlated with an exponential dependency on (diffusion coefficient {times} time){sup {1/2}}/thickness and provided diffusion coefficients for air components into, and blowing agent out of, the foam. This aging procedure was used to predict the five-year thermal resistivity of the foams. The thin-specimen aging procedure is supported with calculations by a computer model for aging of foams. 43 refs., 33 figs., 25 tabs.

McElroy, D.L.; Graves, R.S.; Yarbrough, D.W.; Weaver, F.J.

1991-09-01T23:59:59.000Z

106

Atmospheric chemistry of FO[sub 2] radicals. Reaction with Ch[sub 4], O[sub 3], NO, NO[sub 2], and CO at 295 K  

SciTech Connect (OSTI)

Using pulse radiolysis combined with UV absorption spectroscopy, upper limits for the rate constants of the reaction of the FO[sub 2] radical with O[sub 3], CH[sub 4], and CO were determined to be <3.4 x 10[sup [minus]16], <4.1 x 10[sup [minus]15], and <5.1 x 10[sup [minus]16] cm[sup 3] molecule[sup [minus]1] s[sup [minus]1], respectively. The rate constants for the reactions of FO[sub 2] radicals with NO and NO[sub 2] were measured: FO[sub 2] + NO [yields] FNO + O[sub 2] (10a); FO[sub 2] + NO[sub 2] [yields] products (11). The rate constants for reactions 10 and 11 were determined to be (1.47 [+-] 0.08) x 10[sup [minus]12] and (1.05 [+-] 0.15) x 10[sup [minus]13] cm[sup 3] molecule[sup [minus]1] s[sup [minus]1], respectively. Reaction 10a was found to give FNO in a yield of 100 [+-] 14%. As a part of this work, an upper limit of the reaction of FO radicals with O[sub 3] was determined to be <1.2 x 10[sup [minus]12] cm[sup 3] molecule[sup [minus]1] s[sup [minus]1]. Results are discussed in the context of the atmospheric chemistry of the FO[sub 2] radical and hydrofluorocarbons. 23 refs., 12 figs., 2 tabs.

Sehested, J.; Sehested, K.; Nielsen, O.J. (Riso National Lab., Roskilde (Denmark)); Wallington, T.J. (Ford Motor Company, Dearborn, MI (United States))

1994-07-07T23:59:59.000Z

107

Demonstration of High Efficiency Elastocaloric Cooling with Large Delta- T Using NiTi Wires  

SciTech Connect (OSTI)

Vapor compression (VC) is by far the most dominant technology for meeting all cooling and refrigeration needs around the world. It is a mature technology with the efficiency of modern compressors approaching the theoretical limit, but its envi-ronmental footprint remains a global problem. VC refrigerants such as hydrochlo-roflurocarbons (HCFCs) and hydrofluorocarbons (HFCs) are a significant source of green house gas (GHG) emissions, and their global warming potential (GWP) is as high as 1000 times that of CO2. It is expected that building space cooling and re-frigeration alone will amount to {approx} 5% of primary energy consumption and {approx}5% of all CO2 emission in U.S. in 2030 . As such, there is an urgent need to develop an al-ternative high-efficiency cooling technology that is affordable and environmentally friendly. Among the proposed candidates, magnetocaloric cooling (MC) is currently received a lot of attention because of its high efficiency. However, MC is inherently expensive because of the requirement of large magnetic field and rare earth materi-als. Here, we demonstrate an entirely new type of solid-state cooling mechanism based on the latent heat of reversible martensitic transformation. We call it elasto-caloric cooling (EC) after the superelastic transformation of austenite it utilizes. The solid-state refrigerant of EC is cost-effective, and it completely eliminates the use of any refrigerants including HCFCs/HFCs. We show that the COP (coefficient of per-formance) of a jugular EC with optimized materials can be as high as > 10 with measured {Delta}T of 17 C.

Cui, Jun; Wu, Yiming; Muehlbauer, Jan; Hwang, Yunho; Radermacher, Reinhard; Fackler, Sean; Wuttig, Manfred; Takeuchi, Ichiro

2012-08-01T23:59:59.000Z

108

EIA - Greenhouse Gas Emissions Overview  

Gasoline and Diesel Fuel Update (EIA)

1. Greenhouse Gas Emissions Overview 1. Greenhouse Gas Emissions Overview 1.1 Total emissions Total U.S. anthropogenic (human-caused) greenhouse gas emissions in 2009 were 5.8 percent below the 2008 total (Table 1). The decline in total emissions-from 6,983 million metric tons carbon dioxide equivalent (MMTCO2e) in 2008 to 6,576 MMTCO2e in 2009-was the largest since emissions have been tracked over the 1990-2009 time frame. It was largely the result of a 419-MMTCO2e drop in carbon dioxide (CO2) emissions (7.1 percent). There was a small increase of 7 MMTCO2e (0.9 percent) in methane (CH4) emissions, and an increase of 8 MMTCO2e (4.9 percent), based on partial data, in emissions of man-made gases with high global warming potentials (high-GWP gases). (Draft estimates for emissions of HFC and PFC

109

Experimental study and analysis on components of a thermoacoustic refrigerator and thermoacoustic prime mover  

SciTech Connect (OSTI)

A thermoacoustic refrigerator and a thermoacoustic prime mover, due to its simple structure, would serve as very desirable systems because thermoacoustic prime movers can be driven with the waste heat such as an exhaust gas from engines, and with heat from the nature such as sunlight and a geothermal heat. The thermoacoustic refrigerator and the thermoacoustic prime mover combined would serve as a perfect cooling system without moving parts, CFC's and HFC's. Thus this Thermoacoustic-driven Thermoacoustic Refrigerator will replace the previous paper compression refrigeration system. The authors set up the thermoacoustic refrigerator and thermoacoustic prime mover to investigate the fundamental characteristics. On the refrigerator tests, dimensions of the stack are varied as a parameter of experiments. As a result, influences of the stack configuration on the performance are confirmed, so the design method for the optimum dimension to attain the large temperature difference can be indicated. About the prime mover tests, fundamental characteristics of stack dimensions is checked. The way to improve the thermal efficiency of the prime mover is mentioned in terms of the operating condition. Numerical calculations about the refrigerator are made which is based on the enthalpy flow model by Radebaugh. The result of calculations has a good agreement in quality with the experimental results, so the propriety of this model is confirmed.

Nohtomi, Makoto; Katsuta, Masafumi

1999-07-01T23:59:59.000Z

110

Comparison of the activity and selectivity of activated carbon supported group VIII metal catalysts in the hydrogenolysis of CCl{sub 2}F{sub 2} into CH{sub 2}F{sub 2}  

SciTech Connect (OSTI)

The catalytic hydrogenolysis of waste and banked CCl{sub 2}F{sub 2} (CFC-12) is important for the reduction of ozone depletion caused by CFCs. Especially selective production of CH{sub 2}F{sub 2} (HFC-32) is attractive, because this product can be applied as an alternative, ozone friendly, refrigerant. Because of the limited time available for catalyst development, interaction between catalyst and process development is crucial. Several group VIII metal supported catalyst have been tested for the reaction. Activated carbon is selected as support material because of the corrosive reaction conditions. Large differences in both the activity and selectivity are found for the different metals. Palladium has been selected as very suitable for the selective conversion to CH{sub 2}F{sub 2} (85% selectivity at 90% conversion, stable for 1600 hours). Iridium and ruthenium are more selective to CHClF{sub 2} (HCFC-22) (60% and 53% selectivity at 15% and 20% conversion, respectively). In this presentation the different performances of the Group VIII metals will be illustrated with both performance and characterization data.

Wiersma, A.; Hollander, M.A. den; Makkee, M. [Delft Univ. of Technology (Netherlands)] [and others

1996-10-01T23:59:59.000Z

111

Saturated critical heat flux in a multi-microchannel heat sink fed by a split flow system  

SciTech Connect (OSTI)

An extensive experimental campaign has been carried out for the measurement of saturated critical heat flux in a multi-microchannel copper heat sink. The heat sink was formed by 29 parallel channels that were 199 {mu}m wide and 756 {mu}m deep. In order to increase the critical heat flux and reduce the two-phase pressure drop, a split flow system was implemented with one central inlet at the middle of the channels and two outlets at either end. The base critical heat flux was measured using three HFC Refrigerants (R134a, R236fa and R245fa) for mass fluxes ranging from 250 to 1500 kg/m{sup 2} s, inlet subcoolings from -25 to -5 K and saturation temperatures from 20 to 50 C. The parametric effects of mass velocity, saturation temperature and inlet subcooling were investigated. The analysis showed that significantly higher CHF was obtainable with the split flow system (one inlet-two outlets) compared to the single inlet-single outlet system, providing also a much lower pressure drop. Notably several existing predictive methods matched the experimental data quite well and quantitatively predicted the benefit of higher CHF of the split flow. (author)

Mauro, A.W.; Toto, D. [Department of Energetics, Applied Thermofluidynamics and Air Conditioning Systems, FEDERICO II University, p.le Tecchio 80, 80125 Napoli (Italy); Thome, J.R. [Laboratory of Heat and Mass Transfer (LTCM), Faculty of Engineering (STI), Ecole Polytechnique Federale de Lausanne (EPFL), Station 9, Lausanne CH-1015 (Switzerland); Vanoli, G.P. [Engineering Department, Sannio University, Corso Garibaldi 107, Palazzo dell'Aquila Bosco Lucarelli, 82100 Benevento (Italy)

2010-01-15T23:59:59.000Z

112

Global warming and end-use efficiency implications of replacing CFCs  

SciTech Connect (OSTI)

The direct contribution of CFCs to calculated global warming has been recognized for some time. As a result of the international agreement to phase out CFCs due to stratospheric ozone and the ensuing search for suitable alternatives, there has recently been increased attention on the DIRECT global warming potential (GWP) of the fluorocarbon alternatives as greenhouse gases. However, to date there has been little focus on the INDIRECT global warming effect arising from end-use efficiency changes and associated CO{sub 2} emissions. A study being conducted at Oak Ridge National Laboratory (ORNL) addresses this combined or total global warming impact of viable options to replace CFCs in their major energy-related applications. This paper reviews selected results for air-conditioning, refrigeration, and heat pump applications. The analysis indicates that the CFC user industries have made substantial progress in approaching near-equal energy efficiency with the HCFC/HFC alternative refrigerants. The findings also bring into question the relative importance of the DIRECT (chemical-related) effect in many applications. Replacing CFCs is an important step in reducing the total global warming impact, and at present the HCFC and HFCS appear to offer the best efficiency and lowest total impact of options available in the relatively short time period required for the transition away from CFCs.

Fairchild, P.D.; Fischer, S.K.

1991-12-31T23:59:59.000Z

113

Evaporation heat transfer and friction characteristics of R-134a flowing downward in a vertical corrugated tube  

SciTech Connect (OSTI)

Differently from most previous studies, the heat transfer and friction characteristics of the pure refrigerant HFC-134a during evaporation inside a vertical corrugated tube are experimentally investigated. The double tube test sections are 0.5 m long with refrigerant flowing in the inner tube and heating water flowing in the annulus. The inner tubes are one smooth tube and two corrugated tubes, which are constructed from smooth copper tube of 8.7 mm inner diameter. The test runs are performed at evaporating temperatures of 10, 15, and 20 C, heat fluxes of 20, 25, and 30 kW/m{sup 2}, and mass fluxes of 200, 300, and 400 kg/m{sup 2} s. The quality of the refrigerant in the test section is calculated using the temperature and pressure obtained from the experiment. The pressure drop across the test section is measured directly by a differential pressure transducer. The effects of heat flux, mass flux, and evaporation temperature on the heat transfer coefficient and two-phase friction factor are also discussed. It is found that the percentage increases of the heat transfer coefficient and the two-phase friction factor of the corrugated tubes compared with those of the smooth tube are approximately 0-10% and 70-140%, respectively. (author)

Aroonrat, Kanit; Wongwises, Somchai [Fluid Mechanics, Thermal Engineering and Multiphase Flow Research Lab. (FUTURE), Department of Mechanical Engineering, King Mongkut's University of Technology Thonburi, Bangmod, Bangkok 10140 (Thailand)

2011-01-15T23:59:59.000Z

114

Interaction phenomena at reactive metal/ceramic interfaces.  

SciTech Connect (OSTI)

The objective of this study was to understand the interface chemical reactions between stable ceramics and reactive liquid metals, and developing microstructure. Experiments were conducted at elevated temperatures where small metal samples of Zr and Zr-alloy were placed on top of selected oxide and non-oxide ceramic substrates (Y{sub 2}O{sub 3}, ZrN, ZrC, and HfC). The sample stage was heated in high-purity argon to about 2000 C, held in most cases for five minutes at the peak temperature, and then cooled to room temperature at {approximately}20 c/min. An external video camera was used to monitor the in-situ wetting and interface reactions. Post-test examinations of the systems were conducted by scanning electron microscopy and energy dispersive spectroscopy. It was determined that the Zr and the Zr-alloy are very active in the wetting of stable ceramics at elevated temperatures. In addition, in some systems, such as Zr/ZrN, a reactive transition phase formed between the ceramic and the metal. In other systems, such as Zr/Y{sub 2}O{sub 3}, Zr/ZrC and Zr/HfC, no reaction products formed, but a continuous and strong joint developed under these circumstances also.

McDeavitt, S. M.; Billings, G. W.; Indacochea, J. E.

2000-11-03T23:59:59.000Z

115

Performance characteristics of a turbo expander substituted for expansion valve on air-conditioner  

Science Journals Connector (OSTI)

An experimental study is conducted on a small turbo expander which could be applied to the expansion process in place of expansion valves in refrigerator or air-conditioner to improve the cycle efficiency by recovering energy from the throttling process. The operating gas is \\{HFC134a\\} and the maximum cooling capacity of experiment apparatus is 32.7kW. Four different turbo expanders are tested to find the performance characteristics of the turbo expander when they operate at a low partial admission rate. The partial admission rate is 1.70% or 2.37, and expanders are operated in the supersonic flow. In the experiment, pressure and temperature are measured at 10 different locations in the experimental apparatus. In addition to these measurements, output power at the turbo expander is measured through a generator installed on a rotor shaft with the rotational speed. Performance data of the turbo expander are obtained at many part load operations by adjusting the output power of the generator. A maximum of 15.8% total-to-static efficiency is obtained when the pressure ratio and the partial admission ratio are 2.37 and 1.70%, respectively. Experimental results show that the optimal velocity ratio decreases when the pressure ratio is decreased, and peak efficiencies, which are obtained at locally maximized efficiency depending on the operating condition, vary linearly against the subcooling temperature or the pressure ratio.

Soo-Yong Cho; Chong-Hyun Cho; Chaesil Kim

2008-01-01T23:59:59.000Z

116

Performance characteristics of a turbo expander substituted for expansion valve on air-conditioner  

SciTech Connect (OSTI)

An experimental study is conducted on a small turbo expander which could be applied to the expansion process in place of expansion valves in refrigerator or air-conditioner to improve the cycle efficiency by recovering energy from the throttling process. The operating gas is HFC134a and the maximum cooling capacity of experiment apparatus is 32.7 kW. Four different turbo expanders are tested to find the performance characteristics of the turbo expander when they operate at a low partial admission rate. The partial admission rate is 1.70% or 2.37, and expanders are operated in the supersonic flow. In the experiment, pressure and temperature are measured at 10 different locations in the experimental apparatus. In addition to these measurements, output power at the turbo expander is measured through a generator installed on a rotor shaft with the rotational speed. Performance data of the turbo expander are obtained at many part load operations by adjusting the output power of the generator. A maximum of 15.8% total-to-static efficiency is obtained when the pressure ratio and the partial admission ratio are 2.37 and 1.70%, respectively. Experimental results show that the optimal velocity ratio decreases when the pressure ratio is decreased, and peak efficiencies, which are obtained at locally maximized efficiency depending on the operating condition, vary linearly against the subcooling temperature or the pressure ratio. (author)

Cho, Soo-Yong [Department of Mechanical and Aerospace Engineering (ReCAPT), Gyeongsang National University, 900 Gajoa-dong, Jinju 660-701 (Korea); Cho, Chong-Hyun [School of Mechanical and Aerospace Engineering, Gyeongsang National University, 900 Gajoa-dong, Jinju 660-701 (Korea); Kim, Chaesil [Department of Mechanical Engineering, Changwon National University, 9 Sarim-dong, Changwon 641-773 (Korea)

2008-09-15T23:59:59.000Z

117

Software/firmware design specification for 10 MW/sub e/ Solar Thermal Central Receiver Pilot Plant  

SciTech Connect (OSTI)

This Collector Subsystem Software/Firmware Design Specification exists as a stand-alone document to provide a complete description of the software and firmware employed for the operation of the 10 MWe Solar Thermal Central Receiver Pilot Plant Collector Subsystem. The software/firmware systems have the capability to allow operator control of up to 2048 heliostats in the operation of the 10 MWe Solar Thermal Central Receiver Pilot Plant at Barstow, California. This function includes the capability of operator-commanded mode control, graphic displays, status displays, alarm generation, system redundancy and interfaces to the Operational Control System (OCS), the Data Acquisition System (DAS), and the Beam Characterization System (BCS) through the OCS. The operational commands will provide for the following: (a) safe beam movement whenever automatic beam movement is required; (b) single and multiple heliostat addressing; (c) emergency heliostat movement for high-wind conditions and receiver problems; and (d) recovery for full or partial power-loss conditions. The control hardware consists of a host computer, the Heliostat Array Controller (HAC), interfaced to a group of communication controllers, the Heliostat Field Controllers (HFCs), communicating with individual processors, the Heliostat Controllers (HCs), which monitor and command a single heliostat. The system consists of two HACs and 64 HFCs with up to 32 HCs per HFC.

Ladewig, T.D.

1982-01-01T23:59:59.000Z

118

Thin Film Solid-State Reactions Forming Carbides as Contact Materials for Carbon-Containing Semiconductors  

SciTech Connect (OSTI)

Metal carbides are good candidates to contact carbon-based semiconductors (SiC, diamond, and carbon nanotubes). Here, we report on an in situ study of carbide formation during the solid-state reaction between thin films. The solid-state reaction was examined between 11 transition metals (W, Mo, Fe, Cr, V, Nb, Mn, Ti, Ta, Zr, and Hf) and an amorphous carbon layer. Capping layers (C or TiN) of different thicknesses were applied to prevent oxidation. Carbide formation is evidenced for nine metals and the phases formed have been identified (for a temperature ranging from 100 to 1100 C). W first forms W{sub 2}C and then WC; Mo forms Mo{sub 2}C; Fe forms Fe{sub 3}C; Cr first forms metastable phases Cr{sub 2}C and Cr{sub 3}C{sub 2-x}, and finally forms Cr{sub 3}C{sub 2}; V forms VC{sub x}; Nb transforms into Nb{sub 2}C followed by NbC; Ti forms TiC; Ta first forms Ta{sub 2}C and then TaC; and Hf transforms into HfC. The activation energy for the formation of the various carbide phases has been obtained by in situ x-ray diffraction.

Leroy,W.; Detavernier, C.; Van Meirhaeghe, R.; Lavoie, C.

2007-01-01T23:59:59.000Z

119

An evaluation on the environmental consequences of residual CFCs from obsolete household refrigerators in China  

SciTech Connect (OSTI)

Chlorofluorocarbons (CFCs) contained in household refrigerators consist mainly of CFC-11 and CFC-12, which will be eventually released into the environment. Consequentially, environmental releases of these refrigerants will lead to ozone depletion and contribute significantly to the greenhouse effect, if waste refrigerators are not disposed of properly. In the present paper, the potential release of residual CFCs and their substitutes from obsolete household refrigerators in China is examined, and their contributions to ozone depletion and greenhouse effect are compared with those of other recognized ozone-depleting substances (ODS) and greenhouse gases (GHGs). The results imply that annual potential amounts of released residual CFC-11 and CFC-12 will reach their maximums at 4600 and 2300 tons, respectively in 2011, and then decrease gradually to zero until 2020. Meanwhile, the amounts of their most widely used substitutes HCFC-141b and HFC-134a will keep increasing. Subsequently, the contribution ratio of these CFCs and their substitutes to ozone depletion will remain at 25% through 2011, and reach its peak value of 34% by 2018. The contribution to greenhouse effect will reach its peak value of 0.57% by 2010. Moreover, the contribution ratio of these CFCs to the total global release of CFCs will steadily increase, reaching its peak of 15% by 2018. Thus, this period from 2010 to 2018 is a crucial time during which residual CFCs and their substitutes from obsolete household refrigerators in China will contribute significantly to ozone depletion.

Zhao Xiangyang; Duan Huabo [Department of Environmental Science and Engineering, Tsinghua University, Beijing (China); Li Jinhui, E-mail: jinhui@tsinghua.edu.cn [Department of Environmental Science and Engineering, Tsinghua University, Beijing (China)

2011-03-15T23:59:59.000Z

120

Greenhouse Gas Management Program Overview (Fact Sheet)  

SciTech Connect (OSTI)

Program fact sheet highlighting federal requirements for GHG emissions management, FEMP services to help agencies reduce emissions, and additional resources. The U.S. Department of Energy (DOE) Federal Energy Management Program (FEMP) assists Federal agencies with managing their greenhouse gas (GHG) emissions. GHG management entails measuring emissions and understanding their sources, setting a goal for reducing emissions, developing a plan to meet this goal, and implementing the plan to achieve reductions in emissions. FEMP provides the following services to help Federal agencies meet the requirements of inventorying and reducing their GHG emissions: (1) FEMP offers one-on-one technical assistance to help agencies understand and implement the Federal Greenhouse Gas Accounting and Reporting Guidance and fulfill their inventory reporting requirements. (2) FEMP provides training, tools, and resources on FedCenter to help agencies complete their annual inventories. (3) FEMP serves a leadership role in the interagency Federal Working Group on Greenhouse Gas Accounting and Reporting that develops recommendations to the Council on Environmental Quality (CEQ) for the Federal Greenhouse Gas Accounting and Reporting Guidance. (4) As the focus continues to shift from measuring emissions (completing inventories) to mitigating emissions (achieving reductions), FEMP is developing a strategic planning framework and resources for agencies to prioritize among a variety of options for mitigating their GHG emissions, so that they achieve their reduction goals in the most cost-effective manner. These resources will help agencies analyze their high-quality inventories to make strategic decisions about where to use limited resources to have the greatest impact on reducing emissions. Greenhouse gases trap heat in the lower atmosphere, warming the earth's surface temperature in a natural process known as the 'greenhouse effect.' GHGs include carbon dioxide (CO{sub 2}), methane (CH{sub 4}), nitrous oxide (N{sub 2}O), perfluorocarbons (PFCs), hydrofluorocarbons (HFCs), and sulfur hexafluoride (SF{sub 6}). Human activities have caused a rapid increase in GHG concentrations. This rising level contributes to global climate change, which contributes to environmental and public health problems.

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2011-11-01T23:59:59.000Z

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121

Evaluation of design options for improving the energy efficiency of an environmentally safe domestic refrigerator-freezer  

SciTech Connect (OSTI)

In order to reduce greenhouse emissions from power plants and respond to regulatory actions arising from the National Appliance Energy Conservation Act (NAECA), several design options were investigated for improving the energy efficiency of a conventionally designed, domestic refrigerator-freezer. The options, such as improved cabinet insulation and high-efficiency compressor and fans, were incorporated into a prototype refrigerator-freezer cabinet and refrigeration system to produce a unit that is superior from an environmental viewpoint due to its lower energy consumption and the use of refrigerant HFC-134a as a replacement for CFC-12. Baseline energy performance of the original 1993 production refrigerator-freezer, along with cabinet heat load and compressor calorimeter test results, were extensively documented to provide a firm basis for experimentally measured energy savings. A detailed refrigerator system computer model was used to evaluate the energy savings for several design modifications that, collectively, could achieve a targeted energy consumption of 1.00 kWh/d for a 20 ft{sup 3} (570 l) top-mount, automatic-defrost, refrigerator-freezer. The energy consumption goal represents a 50% reduction in the 1993 NAECA standard for units of this size. Following the modeling simulation, laboratory prototypes were fabricated and tested to experimentally verify the analytical results and aid in improving the model in those areas where discrepancies occurred. While the 1.00 kWh/d goal was not achieved with the modifications, a substantial energy efficiency improvement of 22% (1.41 kWh/d) was demonstrated using near-term technologies. It is noted that each improvement exacts a penalty in terms of increased cost or system complexity/reliability. Further work on this project will analyze cost-effectiveness of the design changes and investigate alternative, more-elaborate, refrigeration system changes to further reduce energy consumption.

Vineyard, E.A.; Sand, J.R. [Oak Ridge National Lab., TN (United States); Bohman, R.H.

1995-03-01T23:59:59.000Z

122

Development of single crystal filaments. Final report  

SciTech Connect (OSTI)

The program just completed addresses a route to a more efficient longer-lasting electric light bulb filament. All current filaments for light bulbs are metallic in nature. They are subject to embrittlement with age (large grain growth) and relatively high vapor pressures which limits their operating temperature. There is evidence which suggests advantages to using high temperature refractory single crystal fibers as a filament for a light bulb. These refractory materials may include materials such as hafnium or tantalum carbide which have melting points about 500{degrees}C higher than tungsten. Another advantage is that single crystal fibers have a very high degree of crystalline perfection with very few voids and dislocations. Without these imperfections, the atomic mobility at high temperatures is highly restricted. Thus single crystal fibers are very stable at high temperature and will last longer. The efficiencies result from running these single crystal ceramic fiber filaments at higher temperatures and the higher emissivity of the carbide filaments compared to tungsten. The amount of visible light is proportional to the 4the power of the temperature thus a 500{degrees}C higher operating give about a 3-fold increase in radiation in the visible range. The program accomplishments can be summarized as follows: (1) Single crystal fibers of JfC sufficient crystal quality for light bulb filament applications were made. (2) The HfC fiber furnace growth chamber, power control and data collection system was developed for the laboratory scale plant. (3) method for mounting and apparatuses for testing the single crystal fiber filaments were developed and built.

Milewski, J.V.; Shoultz, R.A.; Bourque-McConnell, M.M.

1995-04-01T23:59:59.000Z

123

Solvated Electron Technology{sup TM}. Non-Thermal Alternative to Waste Incineration  

SciTech Connect (OSTI)

Solvated Electron Technology (SET{sup TM}) is a patented non-thermal alternative to incineration for treating Toxic Substances Control Act (TSCA) and other mixed waste by destroying organic hazardous components. SET{sup TM} is a treatment process that destroys the hazardous components in mixed waste by chemical reduction. The residual material meets land disposal restriction (LDR) and TSCA requirements for disposal. In application, contaminated materials are placed into a treatment cell and mixed with the solvated electron solution. In the case of PCBs or other halogenated contaminants, chemical reactions strip the halogen ions from the chain or aromatic ring producing sodium chloride and high molecular weight hydrocarbons. At the end of the reaction, ammonia within the treatment cell is removed and recycled. The reaction products (such as sodium salts) produced in the process remain with the matrix. The SET{sup TM} process is 99.999% effective in destroying: polychlorinated biphenyls (PCBs); trichloroethane (TCA) and trichloroethene (TCE); dioxins; polycyclic aromatic hydrocarbons (PAHs); benzene, toluene, xylene (BTX); pesticides; fungicides; herbicides; chlorofluorocarbons (CFCs); hydro-chlorofluorocarbons (HCFCs), explosives and chemical-warfare agents; and has successfully destroyed many of the wastes listed in 40 Code of Federal Regulations (CFR) 261. In September 2007, U.S. Environmental Protection Agency (EPA) issued a Research and Development permit for SET for chemical destruction of 'pure' Pyranol, which is 60% PCBs. These tests were completed in November 2007. SET{sup TM} is recognized by EPA as a non-thermal process equivalent to incineration and three SET{sup TM} systems have been permitted by EPA as commercial mobile PCB destruction units. This paper describes in detail the results of select bench-, pilot-, and commercial-scale treatment of hazardous and mixed wastes for EPA, Department of Energy (DOE), and the Department of Defense(DoD), and the applicability of SET{sup TM} to currently problematic waste streams that have very limited treatment alternatives. In summary: SET{sup TM} operates as a non-thermal destruction process under low pressure. The process occurs in a closed system producing no hazardous off-gases and no regulated by-products such as dioxins or furans or their precursors. Advantages of SET{sup TM} include: - Organic contaminants are destroyed, not just removed, diluted or concentrated. - Operates as a closed system - produces no regulated secondary wastes. - Holds an EPA permit for PCB destruction. - Operates at ambient temperatures (70 deg. F). - Portable and sets up quickly in less than 4000 square feet of space. - Scalable to accommodate any size waste stream. - Requires minimal amounts of power, water and infrastructure. - Applicable to heterogeneous waste streams in all phases. The SET{sup TM} process is 99.9999% effective in destroying organic constituents of RCRA and TSCA waste, explosives and chemical-warfare agents; and has successfully destroyed many of the wastes listed in 40 Code of Federal Regulations (CFR) 261. The residual material meets land disposal restriction (LDR) and TSCA requirements for disposal. In November 2007, Commodore completed a treatability study on Pyranol to determine the effectiveness of SET{sup TM} treatment on oil containing 600,000 PPM PCBs. Laboratory results proved destruction of PCBs to less than 1 PPM at low temperatures and pressures. SET{sup TM} is a proven, safe and cost-effective alternative to incineration for some of the most difficult waste treatment problems that exist today. (authors)

Foutz, W.L.; Rogers, J.E.; Mather, J.D. [Commodore Advanced Sciences, Inc., Richland, WA (United States)

2008-07-01T23:59:59.000Z

124

DOE/AHAM advanced refrigerator technology development project  

SciTech Connect (OSTI)

As part of the effort to improve residential energy efficiency and reduce greenhouse emissions from power plants, several design options were investigated for improving the energy efficiency of a conventionally designed domestic refrigerator-freezer. The program goal was to reduce the energy consumption of a 20-ft{sup 3} (570-L) top-mount refrigerator-freeze to 1.00 kWh/d, a 50% reduction from the 1993 National Appliance Energy Conservation Act (NAECA) standard. The options--such as improved cabinet and door insulation, a high-efficiency compressor, a low-wattage fan, a large counterflow evaporator, and adaptive defrost control--were incorporated into prototype refrigerator-freezer cabinets and refrigeration systems. The refrigerant HFC-134a was used as a replacement for CFC-12. The baseline energy performance of the production refrigerator-freezers, along with cabinet heat load and compressor calorimeter test results, were extensively documented to provide a firm basis for experimentally measured energy savings. The project consisted of three main phases: (1) an evaluation of energy-efficient design options using computer simulation models and experimental testing, (2) design and testing of an initial prototype unit, and (3) energy and economic analyses of a final prototype. The final prototype achieved an energy consumption level of 0.93 kWh/d--an improvement of 45% over the baseline unit and 54% over the 1993 NAECA standard for 20-fg{sup 3} (570-L) units. The manufacturer`s cost for those improvements was estimated at $134; assuming that cost is doubled for the consumer, it would take about 11.4 years to pay for the design changes. Since the payback period was thought to be unfeasible, a second, more cost-effective design was also tested. Its energy consumption level was 1.16 kWh/d, a 42% energy savings, at a manufacturer`s cost increase of $53. Again assuming a 100% markup, the payback for this unit would be 6.6 years.

Vineyard, E.A.; Sand, J.R.; Rice, C.K.; Linkous, R.L.; Hardin, C.V.; Bohman, R.H.

1997-03-01T23:59:59.000Z

125

Advanced separation technology for flue gas cleanup. Topical report  

SciTech Connect (OSTI)

The objective of this work is to develop a novel system for regenerable SO{sub 2} and NO{sub x} scrubbing of flue gas that focuses on (1) a novel method for regenerating spent SO{sub 2} scrubbing liquor and (2) novel chemistry for reversible absorption of NO{sub x}. In addition, high efficiency hollow fiber contactors (HFC) are proposed as the devices for scrubbing the SO{sub 2} and NO{sub x} from the flue gas. The system will be designed to remove more than 95% of the SO{sub 2} and more than 75% of the NO{sub x} from flue gases typical of pulverized coal-fired power plants at a cost that is at least 20% less than combined wet limestone scrubbing of SO{sub x} and selective catalytic reduction of NO{sub x}. The process will generate only marketable by-products. Our approach is to reduce the capital cost by using high-efficiency hollow fiber devices for absorbing and desorbing the SO{sub 2} and NO{sub x}. We will also introduce new process chemistry to minimize traditionally well-known problems with SO{sub 2} and NO{sub x} absorption and desorption. Our novel chemistry for scrubbing NO{sub x} will consist of water-soluble phthalocyanine compounds invented by SRI as well as polymeric forms of Fe{sup ++} complexes similar to traditional NO{sub x} scrubbing media. The final novelty of our approach is the arrangement of the absorbers in cassette (stackable) form so that the NO{sub x} absorber can be on top of the SO{sub x} absorber. This arrangement is possible only because of the high efficiency of the hollow fiber scrubbing devices, as indicated by our preliminary laboratory data. This arrangement makes it possible for the SO{sub 2} and NO{sub x} scrubbing chambers to be separate without incurring the large ducting and gas pressure drop costs necessary if a second conventional absorber vessel were used. Because we have separate scrubbers, we will have separate liquor loops and simplify the chemical complexity of simultaneous SO{sub 2}/NO{sub x} scrubbing.

Bhown, A.S.; Alvarado, D.; Pakala, N.; Ventura, S. [and others

1995-01-01T23:59:59.000Z

126

Hybrid Membrane/Absorption Process for Post-combustion CO2 Capture  

SciTech Connect (OSTI)

This report summarizes scientific/technical progress made for bench-scale membrane contactor technology for post-combustion CO2 capture from DOE Contract No. DE-FE-0004787. Budget Period 1 (BP1) membrane absorber, Budget Period 2 (BP2) membrane desorber and Budget Period 3 (BP3) integrated system and field testing studies have been completed successfully and met or exceeded the technical targets (? 90% CO2 removal and CO2 purity of 97% in one membrane stage). Significant breakthroughs are summarized below: BP1 research: The feasibility of utilizing the poly (ether ether ketone), PEEK, based hollow fiber contractor (HFC) in combination with chemical solvents to separate and capture at least 90% of the CO2 from simulated flue gases has been successfully established. Excellent progress has been made as we have achieved the BP1 goal: ? 1,000 membrane intrinsic CO2 permeance, ? 90% CO2 removal in one stage, ? 2 psi gas side pressure drop, and ? 1 (sec)-1 mass transfer coefficient. Initial test results also show that the CO2 capture performance, using activated Methyl Diethanol Amine (aMDEA) solvent, was not affected by flue gas contaminants O2 (~3%), NO2 (66 ppmv), and SO2 (145 ppmv). BP2 research: The feasibility of utilizing the PEEK HFC for CO2-loaded solvent regeneration has been successfully established High CO2 stripping flux, one order of magnitude higher than CO2 absorption flux, have been achieved. Refined economic evaluation based on BP1 membrane absorber and BP2 membrane desorber laboratory test data indicate that the CO2 capture costs are 36% lower than DOEs benchmark amine absorption technology. BP3 research: A bench-scale system utilizing a membrane absorber and desorber was integrated into a continuous CO2 capture process using contactors containing 10 to 20 ft2 of membrane area. The integrated process operation was stable through a 100-hour laboratory test, utilizing a simulated flue gas stream. Greater than 90% CO2 capture combined with 97% CO2 product purity was achieved throughout the test. Membrane contactor modules have been scaled from bench scale 2-inch diameter by 12-inch long (20 ft2 membrane surface area) modules to 4-inch diameter by 60-inch long pilot scale modules (165 ft2 membrane surface area). Pilot scale modules were tested in an integrated absorption/regeneration system for CO2 capture field tests at a coal-fired power plant (Midwest Generations Will County Station located in Romeoville, IL). Absorption and regeneration contactors were constructed utilizing high performance super-hydrophobic, nano-porous PEEK membranes with CO2 gas permeance of 2,000 GPU and a 1,000 GPU, respectively. Field tests using aMDEA solvent achieved greater than 90% CO2 removal in a single stage. The absorption mass transfer coefficient was 1.2 (sec)-1, exceeding the initial target of 1.0 (sec)-1. This mass transfer coefficient is over one order of magnitude greater than that of conventional gas/liquid contacting equipment. The economic evaluation based on field tests data indicates that the CO2 capture cost associated with membrane contactor technology is $54.69 (Yr 2011$)/tonne of CO2 captured when using aMDEA as a solvent. It is projected that the DOEs 2025 cost goal of $40 (Yr 2011$)/tonne of CO2 captured can be met by decreasing membrane module cost and by utilizing advanced CO2 capture solvents. In the second stage of the field test, an advanced solvent, Hitachis H3-1 was utilized. The use of H3-1 solvent increased mass transfer coefficient by 17% as compared to aMDEA solvent. The high mass transfer coefficient of H3-1 solvent combined with much more favorable solvent regeneration requirements, indicate that the projected savings achievable with membrane contactor process can be further improved. H3-1 solvent will be used in the next pilot-scale development phase. The integrated absorption/regeneration process design and high performance membrane contactors developed in the current bench-scale program will be used as the base technology for future pilot-scale development.

Li, Shiguang; Shou, S.; Pyrzynski, Travis; Makkuni, Ajay; Meyer, Howard

2013-12-31T23:59:59.000Z

127

Industry  

SciTech Connect (OSTI)

This chapter addresses past, ongoing, and short (to 2010) and medium-term (to 2030) future actions that can be taken to mitigate GHG emissions from the manufacturing and process industries. Globally, and in most countries, CO{sub 2} accounts for more than 90% of CO{sub 2}-eq GHG emissions from the industrial sector (Price et al., 2006; US EPA, 2006b). These CO{sub 2} emissions arise from three sources: (1) the use of fossil fuels for energy, either directly by industry for heat and power generation or indirectly in the generation of purchased electricity and steam; (2) non-energy uses of fossil fuels in chemical processing and metal smelting; and (3) non-fossil fuel sources, for example cement and lime manufacture. Industrial processes also emit other GHGs, e.g.: (1) Nitrous oxide (N{sub 2}O) is emitted as a byproduct of adipic acid, nitric acid and caprolactam production; (2) HFC-23 is emitted as a byproduct of HCFC-22 production, a refrigerant, and also used in fluoroplastics manufacture; (3) Perfluorocarbons (PFCs) are emitted as byproducts of aluminium smelting and in semiconductor manufacture; (4) Sulphur hexafluoride (SF{sub 6}) is emitted in the manufacture, use and, decommissioning of gas insulated electrical switchgear, during the production of flat screen panels and semiconductors, from magnesium die casting and other industrial applications; (5) Methane (CH{sub 4}) is emitted as a byproduct of some chemical processes; and (6) CH{sub 4} and N{sub 2}O can be emitted by food industry waste streams. Many GHG emission mitigation options have been developed for the industrial sector. They fall into three categories: operating procedures, sector-wide technologies and process-specific technologies. A sampling of these options is discussed in Sections 7.2-7.4. The short- and medium-term potential for and cost of all classes of options are discussed in Section 7.5, barriers to the application of these options are addressed in Section 7.6 and the implication of industrial mitigation for sustainable development is discussed in Section 7.7. Section 7.8 discusses the sector's vulnerability to climate change and options for adaptation. A number of policies have been designed either to encourage voluntary GHG emission reductions from the industrial sector or to mandate such reductions. Section 7.9 describes these policies and the experience gained to date. Co-benefits of reducing GHG emissions from the industrial sector are discussed in Section 7.10. Development of new technology is key to the cost-effective control of industrial GHG emissions. Section 7.11 discusses research, development, deployment and diffusion in the industrial sector and Section 7.12, the long-term (post-2030) technologies for GHG emissions reduction from the industrial sector. Section 7.13 summarizes gaps in knowledge.

Bernstein, Lenny; Roy, Joyashree; Delhotal, K. Casey; Harnisch, Jochen; Matsuhashi, Ryuji; Price, Lynn; Tanaka, Kanako; Worrell, Ernst; Yamba, Francis; Fengqi, Zhou; de la Rue du Can, Stephane; Gielen, Dolf; Joosen, Suzanne; Konar, Manaswita; Matysek, Anna; Miner, Reid; Okazaki, Teruo; Sanders, Johan; Sheinbaum Parado, Claudia

2007-12-01T23:59:59.000Z