Enhancing gas production from methane hydrate decomposition by microwave heating-induced: Modeling and experimental validation

Methane hydrate, as an alternative to traditional fossil fuels, can significantly improve the energy structure, arousing substantial research interest. This study develops a three-dimensional model for microwave-induced hydrate dissociation and gas production, incorporating the theory of spatial electromagnetic wave propagation. Experimental results validate the model. The simulation demonstrates that microwave heating technology provides timely and adequate energy, promoting rapid and continuous hydrate decomposition. The spatial distribution of microwave energy leads to faster hydrate dissociation in the upper regions of sediments. Increasing microwave power enhances the average gas production rate but reduces the energy efficiency. To evaluate the influence of initial phase saturation and reservoir sediments physical properties on hydrate dissociation and gas production, the study employs the Pareto optimality criterion to determine the optimal microwave power. Comparisons of energy efficiency under different parameters show that microwave heating is most effective in sediments with lower initial water saturation (Sw0 = 0.18), moderate hydrate saturation (Sh0 = 0.40), lower specific heat capacity, higher thermal conductivity, moderate porosity (ϕ = 0.46), and lower initial absolute permeability. Despite the uncertainties in hydrate decomposition behavior under microwave heating, the results of this study could offer valuable guidance for its practical application in methane hydrate extraction.