Modification of permeability model and history matching of laboratory-scale experiment for dissociation process of methane hydrate: Part 2 - Numerical study for estimation of permeability in methane hydrate reservoir

In this study, for the purpose of history matching a laboratory-scale experiment dissociation of methane hydrate (MH) by hot-water injection, we introduced the MH growth rate into the simulator and modified the numerical model. In addition, we extended the MH phase in the numerical model to a 2-component system by modeling the pore space occupied by MH. Absolute permeability was formulated for an MH 2-component system, and the relative permeability model was also modified as a function of sand grain diam and temperature in addition to MH saturation. As a result, the calculated temperature distribution and gas production behavior during MH dissociation sufficiently agreed with the experimental results. Further, it was found that this developed simulator could reproduce permeability characteristics, associated with both MH formation and dissociation.