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Title: Methane hydrate formation and dissociationin a partially saturatedcore-scale sand sample

Abstract

We performed a series of experiments to provide data forvalidating numerical models of gas hydrate behavior in porous media.Methane hydrate was formed and dissociated under various conditions in alarge X-ray transparent pressure vessel, while pressure and temperaturewere monitored. In addition, X-ray computed tomography (CT) was used todetermine local density changes during the experiment. The goals of theexperiments were to observe changes occurring due to hydrate formationand dissociation, and to collect data to evaluate the importance ofhydrate dissociation kinetics in porous media. In the series ofexperiments, we performed thermal perturbations on the sand/water/gassystem, formed methane hydrate, performed thermal perturbations on thesand/hydrate/water/gas system resulting in hydrate formation anddissociation, formed hydrate in the resulting partially dissociatedsystem, and dissociated the hydrate by depressurization coupled withthermal stimulation. Our CT work shows significant water migration inaddition to possible shifting of mineral grains in response to hydrateformation and dissociation. The extensive data including pressure,temperatures at multiple locations, and density from CT data isdescribed.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
Sponsoring Org.:
USDOE
OSTI Identifier:
918808
Report Number(s):
LBNL-59051
Journal ID: ISSN 0920-4105; JPSEE6; R&D Project: G3W063; TRN: US200819%%453
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Petroleum Science and Engineering; Journal Volume: 56; Journal Issue: 1-3; Related Information: Journal Publication Date: March 2007
Country of Publication:
United States
Language:
English
Subject:
54; COMPUTERIZED TOMOGRAPHY; DEPRESSURIZATION; DISSOCIATION; GAS HYDRATES; HYDRATES; KINETICS; PRESSURE VESSELS; SAND; STIMULATION; WATER; Hydrate formation Dissociation Porous medium Thermalstimulation Depressurization X-ray computed tomography

Citation Formats

Kneafsey, Timothy J., Tomutsa, Liviu, Moridis, George J., Seol,Yongkoo, Freifeld, Barry M., Taylor, Charles E., and Gupta, Arvind. Methane hydrate formation and dissociationin a partially saturatedcore-scale sand sample. United States: N. p., 2006. Web.
Kneafsey, Timothy J., Tomutsa, Liviu, Moridis, George J., Seol,Yongkoo, Freifeld, Barry M., Taylor, Charles E., & Gupta, Arvind. Methane hydrate formation and dissociationin a partially saturatedcore-scale sand sample. United States.
Kneafsey, Timothy J., Tomutsa, Liviu, Moridis, George J., Seol,Yongkoo, Freifeld, Barry M., Taylor, Charles E., and Gupta, Arvind. Fri . "Methane hydrate formation and dissociationin a partially saturatedcore-scale sand sample". United States. doi:.
@article{osti_918808,
title = {Methane hydrate formation and dissociationin a partially saturatedcore-scale sand sample},
author = {Kneafsey, Timothy J. and Tomutsa, Liviu and Moridis, George J. and Seol,Yongkoo and Freifeld, Barry M. and Taylor, Charles E. and Gupta, Arvind},
abstractNote = {We performed a series of experiments to provide data forvalidating numerical models of gas hydrate behavior in porous media.Methane hydrate was formed and dissociated under various conditions in alarge X-ray transparent pressure vessel, while pressure and temperaturewere monitored. In addition, X-ray computed tomography (CT) was used todetermine local density changes during the experiment. The goals of theexperiments were to observe changes occurring due to hydrate formationand dissociation, and to collect data to evaluate the importance ofhydrate dissociation kinetics in porous media. In the series ofexperiments, we performed thermal perturbations on the sand/water/gassystem, formed methane hydrate, performed thermal perturbations on thesand/hydrate/water/gas system resulting in hydrate formation anddissociation, formed hydrate in the resulting partially dissociatedsystem, and dissociated the hydrate by depressurization coupled withthermal stimulation. Our CT work shows significant water migration inaddition to possible shifting of mineral grains in response to hydrateformation and dissociation. The extensive data including pressure,temperatures at multiple locations, and density from CT data isdescribed.},
doi = {},
journal = {Journal of Petroleum Science and Engineering},
number = 1-3,
volume = 56,
place = {United States},
year = {Fri Feb 03 00:00:00 EST 2006},
month = {Fri Feb 03 00:00:00 EST 2006}
}
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