Review of Morphology Studies on Gas Hydrate Formation for Hydrate-Based Technology

Over the past several decades, hydrate-based technology has been thought to have enormous application prospects in the energy and environmental fields. For the further development of hydrate-based technology, it is necessary to investigate the growth behaviors of hydrates and identify the factors that affect their morphology. A morphological study involves the observation of the characteristic appearance of the hydrate, including the shape, size, and mode of hydrate growth, which provides valuable information on the mechanism of hydrate formation, optimizes the industrial process with fast kinetics, and avoids geological hazards. On this basis, this paper reviews the morphology of gas hydrates from two scales, the macroscopic formation of gas hydrates and the crystal morphology of gas hydrates, for the further development of hydrate technology.