Novel Thermokinetic Model for Gas Hydrates: Experimental Validation at Diverse Geological Conditions

Abstract

Most of the natural gas hydrates are found in deep marine sediments and permafrost regions, where the presence of salts and porous media are quite evident. With this, we develop a computationally efficient mathematical model that can expound the clathrate hydrate dynamics in a reservoir-mimicking environment. Along with proposing the chemical potential difference as the driving force to take care of the thermodynamic aspect, a nonstoichiometric reaction with nth-order kinetics is for the first time introduced in the line of adsorption kinetics. To make this thermokinetic model more rigorous, the diffusion part is further formulated with the kinetic factor, along with incorporating various practical aspects, including reaction surface renewal and hydrate formation in nanometer-sized pores of irregular and distributed particles. Finally, to examine the validity of this rigorous model, experimental case studies of methane (CH4) and carbon dioxide (CO2) hydrate formation in various porous media with pure and saline water are used. In addition, we compare the developed model with the existing formulations of gas hydrate dynamics, and it is perceived that the proposed model outperforms the existing models with reference to the experimental data of methane and carbon dioxide hydrate formation at diverse geological conditions.