Numerical simulations for analyzing deformation characteristics of hydrate-bearing sediments during depressurization

Advances in Geo-Energy Research

article

Lele Liu¹  Xiaobing Lu²  Xuhui Zhang²  Changling Liu¹  Bin Du³ 

[1] Key Laboratory of Gas Hydrate, Qingdao Institute of Marine Geology;Institute of Mechanics, Chinese Academy of Sciences;Beijing J & C Geotechnical Construction Ltd.

关键词: Gas hydrate;    hydrate-bearing sediment;    geomechanics;    depressurization;    numerical simulation;   

DOI  :  10.26804/ager.2017.03.01

来源: Yandy Scientific Press

【 摘 要 】

Natural gas hydrates have been treated as a potential energy resource for decades. Understanding geomechanical properties of hydrate-bearing porous media is an essential to protect the safety of individuals and devices during hydrate production. In this work, a numerical simulator named GrapeFloater is developed to study the deformation behavior of hydrate-bearing porous media during depressurization, and the numerical simulator couples multiple processes such as conductive-convective heat transfer, two-phase fluid flow, intrinsic kinetics of hydrate dissociation, and deformation of solid skeleton. Then, a depressurization experiment is carried out to validate the numerical simulator. A parameter sensitivity analysis is performed to discuss the deformation behavior of hydrate-bearing porous media as well as its effect on production responses. Conclusions are drawn as follows: the numerical simulator named GrapeFloater predicts the experimental results well; the modulus of hydrate-bearing porous media has an obvious effect on production responses; final deformation increases with decreasing outlet pressure; both the depressurization and the modulus decrease during hydrate dissociation contribute to the deformation of hydrate-bearing porous media.

【 授权许可】

Unknown