Numerical simulation of methane production from a methane hydrate formation

This paper describes a one-dimensional model for hydrate dissociation in porous media by the depressurization method. A moving boundary, which separates the total simulation zone into two zones, is used. The governing equations consider the convective-conductive heat transfer and mass transfer in the gas and hydrate zones together with the energy balance at the moving front. These equations were transformed into a new coordinate system using a coordinate transformation method. The numerical method of lines was used to discretize the governing equations after coordinate transformation. Distributions of temperature and pressure for different well pressure and reservoir temperature are presented. The speed of the moving front and the gas production rate were shown to be strong functions of the well pressure and the absolute permeability of the porous media. Our simulations also showed that the assumption of stationary water phase, underpredicts gas production and overpredicts the speed of the moving front.