Numerical Study on the Application of In situ Low-temperature Oxidation for Enhanced Recovery from Methane Hydrate Reservoir

摘要

In this study, a new in situ low-temperature oxidation (LTO) process was developed under the concept of effective utilization of heat generation, resulting from LTO of the injected organic substance (IOS), for the promotion of in situ dissociation of methane hydrate (MH) and the enhancement of gas recovery. When water containing the IOS component and air as an oxidant are injected into the MH reservoir, a high-temperature zone by heat generation is formed under the in situ condition. From this process, in addition to MH dissociation, a numerical model considering multicomponent flow in porous media with LTO reaction was constructed. From the calculation results, it was found that the high-temperature zone formed as a result of heat generation extended to the side of the production well, which promoted MH dissociation. In addition, gas recovery as high as 80% to 100% could be obtained through depressurization and in situ LTO process.