Observation of gas hydrate formation at gas-liquid interface

抄録

For development of marine methane hydrate, the characteristics of formation and dissociation of the hydrate in a water flow should be investigated from the viewpoint of flow assurance. In this paper, the formation processes of gas hydrate at a gas-liquid interface under high-pressure conditions were observed using a probe-type video camera. Gas hydrate was formed by injecting enough amount of carbon dioxide into pure water in the pressure chamber in the temperature-pressure region where the hydrate exists thermodynamically stably. Initial crystallization of the hydrate at the gas-liquid interface was observed in a short time. Fine hydrate crystals formed by the initial crystallization were immediately dissolved into the liquid. After agitation, the main crystallization occurred, which provided massive gas hydrate. The massive hydrate remained in the stable temperature-pressure region. It is expected to investigate the dissociation characteristics of the massive hydrate by controlling the temperature and pressure in the chamber.