Modeling and optimization study of gas hydrates: Validation at reservoir-mimicking conditions

Abstract

This work elucidates the fundamental understanding of the natural gas hydrate formation, growth and decomposition dynamics and how these three sequential phases are affected by guest gas composition, salt concentration in constituent water, uneven porous particles with their wide variation in size, ground condition (below sea level and permafrost region), among others. Three phase (hydrate-liquid-vapor) thermodynamic equilibrium has played a central role along with fractional-order kinetics in the complex hydration process. The resulting thermo-kinetic hydrate dynamics involves a set of influential parameters, which need to be determined precisely. For this, a powerful optimization technique, namely simplicial homology global optimization, is introduced for their identification to secure optimal predictability. Using a large variety of datasets at reservoir-mimicking conditions, the hydrate dynamics is well tested with single to multicomponent guest, pure water, salt water and porous media.