LABORATORY STRATEGIES FOR HYDRATE FORMATION IN FINE-GRAINED SEDIMENTS

Handle URI:
http://hdl.handle.net/10754/627519
Title:
LABORATORY STRATEGIES FOR HYDRATE FORMATION IN FINE-GRAINED SEDIMENTS
Authors:
Lei, L. ( 0000-0002-5276-3822 ) ; Santamarina, Carlos ( 0000-0001-8708-2827 )
Abstract:
Fine‐grained sediments limit hydrate nucleation, shift the phase boundary and hinder gas supply. Laboratory experiments in this study explore different strategies to overcome these challenges, including the use of a more soluble guest molecule rather than methane, grain‐scale gas‐storage within porous diatoms, ice‐to‐hydrate transformation to grow lenses at predefined locations, forced gas injection into water saturated sediments, and long‐term guest molecule transport. Tomographic images, thermal and pressure data provide rich information on hydrate formation and morphology. Results show that hydrate formation is inherently displacive in fine‐grained sediments; lenses are thicker and closer to each other in compressible, high specific surface area sediments subjected to low effective stress. Temperature and pressure trajectories follow a shifted phase boundary that is consistent with capillary effects. Exo‐pore growth results in freshly formed hydrate with a striped and porous structure; this open structure becomes an effective pathway for gas transport to the growing hydrate front. Ice‐to‐hydrate transformation goes through a liquid stage at pre‐melt temperatures; then, capillarity and cryogenic suction compete, and some water becomes imbibed into the sediment faster than hydrate reformation. The geometry of hydrate lenses and the internal hydrate structure continue evolving long after the exothermal response to hydrate formation has completely decayed. Multiple time‐dependent processes occur during hydrate formation, including gas, water and heat transport, sediment compressibility, reaction rate and the stochastic nucleation process. Hydrate formation strategies conceived for this study highlight the inherent difficulties in emulating hydrate formation in fine‐grained sediments within the relatively short time‐scale available for laboratory experiments.
KAUST Department:
Physical Sciences and Engineering (PSE) Division; Earth Science and Engineering Program; Ali I. Al-Naimi Petroleum Engineering Research Center (ANPERC)
Citation:
Lei L, Santamarina JC (2018) LABORATORY STRATEGIES FOR HYDRATE FORMATION IN FINE-GRAINED SEDIMENTS. Journal of Geophysical Research: Solid Earth. Available: http://dx.doi.org/10.1002/2017jb014624.
Publisher:
American Geophysical Union (AGU)
Journal:
Journal of Geophysical Research: Solid Earth
Issue Date:
2-Apr-2018
DOI:
10.1002/2017jb014624
Type:
Article
ISSN:
2169-9313
Sponsors:
Seth Mallett helped in the execution of various experiments conducted as part of this study. Gabrielle Abelskamp edited earlier versions of this manuscript. Support for this research was provided by the USA Department of Energy, the Goizueta Foundation and the KAUST endowment. All the experimental data used in this article are available in Lei’s PhD thesis [Lei, 2017].
Additional Links:
https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2017JB014624
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division; Earth Science and Engineering Program; Upstream Petroleum Engineering Research Center (UPERC)

Full metadata record

DC FieldValue Language
dc.contributor.authorLei, L.en
dc.contributor.authorSantamarina, Carlosen
dc.date.accessioned2018-04-16T11:27:43Z-
dc.date.available2018-04-16T11:27:43Z-
dc.date.issued2018-04-02en
dc.identifier.citationLei L, Santamarina JC (2018) LABORATORY STRATEGIES FOR HYDRATE FORMATION IN FINE-GRAINED SEDIMENTS. Journal of Geophysical Research: Solid Earth. Available: http://dx.doi.org/10.1002/2017jb014624.en
dc.identifier.issn2169-9313en
dc.identifier.doi10.1002/2017jb014624en
dc.identifier.urihttp://hdl.handle.net/10754/627519-
dc.description.abstractFine‐grained sediments limit hydrate nucleation, shift the phase boundary and hinder gas supply. Laboratory experiments in this study explore different strategies to overcome these challenges, including the use of a more soluble guest molecule rather than methane, grain‐scale gas‐storage within porous diatoms, ice‐to‐hydrate transformation to grow lenses at predefined locations, forced gas injection into water saturated sediments, and long‐term guest molecule transport. Tomographic images, thermal and pressure data provide rich information on hydrate formation and morphology. Results show that hydrate formation is inherently displacive in fine‐grained sediments; lenses are thicker and closer to each other in compressible, high specific surface area sediments subjected to low effective stress. Temperature and pressure trajectories follow a shifted phase boundary that is consistent with capillary effects. Exo‐pore growth results in freshly formed hydrate with a striped and porous structure; this open structure becomes an effective pathway for gas transport to the growing hydrate front. Ice‐to‐hydrate transformation goes through a liquid stage at pre‐melt temperatures; then, capillarity and cryogenic suction compete, and some water becomes imbibed into the sediment faster than hydrate reformation. The geometry of hydrate lenses and the internal hydrate structure continue evolving long after the exothermal response to hydrate formation has completely decayed. Multiple time‐dependent processes occur during hydrate formation, including gas, water and heat transport, sediment compressibility, reaction rate and the stochastic nucleation process. Hydrate formation strategies conceived for this study highlight the inherent difficulties in emulating hydrate formation in fine‐grained sediments within the relatively short time‐scale available for laboratory experiments.en
dc.description.sponsorshipSeth Mallett helped in the execution of various experiments conducted as part of this study. Gabrielle Abelskamp edited earlier versions of this manuscript. Support for this research was provided by the USA Department of Energy, the Goizueta Foundation and the KAUST endowment. All the experimental data used in this article are available in Lei’s PhD thesis [Lei, 2017].en
dc.publisherAmerican Geophysical Union (AGU)en
dc.relation.urlhttps://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2017JB014624en
dc.rightsArchived with thanks to Journal of Geophysical Research: Solid Earthen
dc.subjectfine-grained sedimentsen
dc.subjecthydrate formationen
dc.subjectcapillarityen
dc.subjectwater migrationen
dc.subjectcryogenic suctionen
dc.subjectsegregated morphologyen
dc.subjectporous hydrateen
dc.subjectmicro-CTen
dc.titleLABORATORY STRATEGIES FOR HYDRATE FORMATION IN FINE-GRAINED SEDIMENTSen
dc.typeArticleen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.contributor.departmentEarth Science and Engineering Programen
dc.contributor.departmentAli I. Al-Naimi Petroleum Engineering Research Center (ANPERC)en
dc.identifier.journalJournal of Geophysical Research: Solid Earthen
dc.eprint.versionPost-printen
dc.contributor.institutionNational Energy Technology Laboratory; U.S. Department of Energy; Morgantown WVen
kaust.authorSantamarina, Carlosen
All Items in KAUST are protected by copyright, with all rights reserved, unless otherwise indicated.