Formation and decomposition of gas hydrates

The kinetics of hydrate formation and decomposition are explained as understood to date. The formation and decomposition phenomena are complex. Hydrate formation is viewed as a crystallization process that includes the nucleation and growth processes. Hydrate nucleation is an intrinsically stochastic process that involves the formation and growth of gas-water clusters to critical sized, stable hydrate nuclei. Hydrate growth process involves the growth of stable hydrate nuclei as solid hydrates. Hydrate decomposition is a sequence of lattice destruction and gas desorption processes. The process of heat transfer during hydrate decomposition is analogous to nucleate boiling phenomena. The focus of this work is to present the various perspectives on the kinetic processes at a conceptual level. Key issues for research in this area are identified and some possible directions for future work are suggested.