Development of an explicit pressure explicit saturation (EPES) method for modelling dissociation processes of methane hydrate

Abstract

ABSTRACT Methane gas is a fossil clean fuel since the products of the combustion are only carbon hydrate and water. Methane hydrate is a potential source of methane gas. This ice-like methane source can be found in deep seafloors and permafrost regions, characterized by high pressure and low-temperature conditions. In this work, we simulate the process of methane hydrate dissociation by depressurization in a cylindrical sandstone core by means of a two-dimensional axis-symmetric model, focusing on the transport phenomena involved in the process. Our simulations indicate a first rapid dissociation phase due to depressurization itself, and a longer subsequent one due to the thermal exchange with the external environment. Our numerical results match well with experimental data found in the literature, without showing any significant pressure or temperature delay among different sections compared to other numerical studies.