Comparative Analysis on the Evolution of Seepage Parameters in Methane Hydrate Production under Depressurization of Clayey Silt Reservoir and Sandy Reservoir

Gas hydrates are likely to become an important strategic resource with commercial development prospects. It is therefore of great significance realize the long-term and efficient production methane hydrate reservoirs. Previous studies have shown that lithological characteristics reservoirs a significant impact on reservoir productivity by influencing evolution seepage parameters in process production. The porosity (?) initial saturation (SH) affect amount decomposition pressure transfer, also indirectly temperature field. permeability (k) directly affects rate pressure-drop transmission gas discharge. Due differences caused different lithology, sandy (SHR) Japan clayey silt (CHR) China were found rates spatial fields varied tests. Therefore, ensure CHR China, two models established for comparative analysis based numerical simulation. depressurizing W11 drilling site Shenhu Sea area South SHR AT1 Eastern Nankai Trough Japan. Both considered heterogeneity parameters, TOUGH+HYDARATE (T+H) code was used subsequent calculations. Four key results obtained: (a) order levels k > SH ? SHR. (b) heat conduction convection weaker than SHR, which made it difficult recover low-temperature decomposition. (c) exploitation high should be given priority when other conditions same both (d) not only rely content or capacity determine potential, but combined effect fully considered.