Numerical study of the effect of over/underburden permeability on methane hydrate dissociation by depressurization

Yongchang Feng, Lin Chen, Hikaru Yamada, Junnosuke Okajima, Atsuki Komiya, Shigenao Maruyama

Research output: Contribution to journalConference articlepeer-review

Abstract

Methane hydrate (MH) is found in larger amounts in the ocean sediments and permafrost regions, and is regarded as one of the potential and substantial energy resources. In general, the hydrate-bearing layer in nature is confined by overburden and underburden. This study is focused on the effect of overburden and underburden permeability on the process of methane hydrate dissociation. Simulation runs are conducted on a hypothetical MH deposit model by depressurization with a single vertical well. Three cases with different permeability in overburden and underburden, including permeable boundaries, semi-permeable boundaries and impermeable boundaries, are used to analyze the influence of heat and fluid transferred from the overburden and underburden on the evolution of temperature, pressure and saturation fields during gas production. The simulation results indicate that the overburden and underburden permeability has a significant effect on the temperature and pressure evolution of hydrate-bearing layer, and gas production during hydrate dissociation. The impermeable boundaries can limit the heat transfer between the hydrate-bearing layer and over/underburden, but intensify the propagation of pressure reduction in the hydrate-bearing layer. For the hydrate deposits with permeable boundaries, hydrate dissociation mainly occurs on the sharp front of dissociation, whereas with impermeable boundaries, hydrate dissociation can occur over a large volume of hydrate-bearing layer. Additionally, it is found that the hydrate deposits with impermeable boundaries have much better gas production performance.

Original languageEnglish
Pages (from-to)6463-6470
Number of pages8
JournalInternational Heat Transfer Conference
Volume2018-August
DOIs
Publication statusPublished - 2018
Event16th International Heat Transfer Conference, IHTC 2018 - Beijing, China
Duration: 2018 Aug 102018 Aug 15

Keywords

  • Depressurization
  • Energy conversion
  • Methane hydrate
  • Multiphase flow
  • Numerical simulation

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Mechanical Engineering
  • Fluid Flow and Transfer Processes

Fingerprint Dive into the research topics of 'Numerical study of the effect of over/underburden permeability on methane hydrate dissociation by depressurization'. Together they form a unique fingerprint.

Cite this