Keyword: «gas hydrate»

The work is devoted to a mathematical modeling of the decomposition of natural gas hydrate in compacted sand samples under decompression. The 1D mathematical model of the process includes equations of mass and heat balance, equation of gas state, equation of gas flow and empirical dependencies related to the kinetics of hydrate dissociation in a porous medium. An empirical dependence of the equilibrium pressure of natural gas hydrate on temperature in a porous medium is used. As a result of the simulation, the distributions of the main physical parameters in the sample and their evolution over time were obtained.

Mathematical modeling methods assess the possibility of natural gas storage by converting them to a hydrate state when gas is injected into permafrost aquifers. The model of multiphase nonisothermal filtration takes into account the main physical features of this process, including gas compressibility, the Joule-Thomson effect, adiabatic expansion, joint movement of water and gas, mass transfer between gas, water and a hydrate. To conduct computational experiments, the results of laboratory experiments of the equilibrium conditions of the natural gas hydrates formation in a free volume and in a porous medium saturated with water and aqueous solutions of sodium bicarbonate were used. The influence of phase equilibrium conditions on the main indicator of the process efficiency – the hydrate saturation of the created storage is studied.