Numerical simulation of gas hydrate dissociation in artificial sediment

Methane Hydrate (MH) is considered to be one of the new-generation energy resources. To support the method of extraction of methane gas from MH, laboratory experiments have been performed at the National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba in Japan. In this paper, we present the results of the numerical simulation of these experiments. In these calculations, Finite Element Heat and Mass Transfer code, developed at the Los Alamos National Laboratory was used. In these experiments, temperature, pressure and cumulative gas production were measured. From this data, we suppose that MH growth/dissociation occurred by the flow of the hot water. Also, we assume that the variation of pressure in this experiment is caused by the change of MH fraction. Thus, we think the ^SH_max This is the maximum fraction of MH. Using the ^SH_max, we express the relation between MH fraction (^SH) and the absolute permeability (^k). This is as follows; k = k_o (1 - ^SH/_{SH_max}) ^N Using this model, we obtain the good match of the behavior of pressure in the experiment.