Abstract
Carbon emission reduction and clean energy development are urgent demands for mankind in the coming decades.Exploring an efficient CO2 storage method can significantly reduce CO2 emissions in the short term.In this study,we attempted to construct sediment samples with different residual CH4 hy-drate amounts and reservoir conditions,and then investigate the potentials of both CO2 storage and enhanced CH4 recovery in depleted gas hydrate deposits in the permafrost and ocean zones,respectively.The results demonstrate that CO2 hydrate formation rate can be significantly improved due to the presence of residual hydrate seeds;However,excessive residual hydrates in turn lead to the decrease in CO2 storage efficiency.Affected by the T-P conditions of the reservoir,the storage amount of liquid CO2 can reach 8 times that of gaseous CO2,and CO2 stored in hydrate form reaches 2-4 times.Additionally,we noticed two other advantages of this method.One is that CO2 injection can enhance CH4 recovery rate and increases CH4 recovery by 10％-20％.The second is that hydrate saturation in the reservoir can be restored to 20％-40％,which means that the solid volume of the reservoir avoids serious shrinkage.Obviously,this is crucial for protecting the goaf stability.In summary,this approach is greatly promising for high-efficient CO2 storage and safe exploitation of gas hydrate.
基金项目
国家自然科学基金(22378424)
国家自然科学基金(52004136)
国家自然科学基金(22127812)
国家自然科学基金(U20B6005)
Science Foundation of China University of Petroleum Beijing(2462023BJRC017)
Hunan Provincial Department of Education Scientific Research Project(22B0310)
万方数据