Research and Development Activities on Methane Hydrate for The Future Energy Resources

摘要

Methane hydrate is a solid material composed of a methane molecule and water molecules. Water molecules form a cage in which a methane molecules was kept at low temperature and high pressure. It is dissociated by increasing temperature and/or releasing pressure. In mid 1960, the first methane hydrate accumulation (deposit) was found in the sediment beneath the permafrost. And also the accumulation have been found in the ocean sediment below see floor over about 500m in depth. In the ocean sediment around Japan, it is estimated that the amount of gas equivalent to today's natural gas consumption for 100 years could be extracted from hydrate reservoirs.When we tried to get gas from the methane hydrate, it is necessary to control the dissociating rate of the hydrate, and the phase control process must be developed through fundamental works on phase equilibrium and kinetics of methane hydrate. The process control system of formation and dissociation of hydrate by considering molecular kinetics is very important for the development at a desirable gas production rate. In this paper, previous researches are outlined on discovery, structure and characteristics, potential for the energy resources and future subjects on the methane hydrate.