To provide a method for the formation of natural gas hydrate of low water content to cut its storage or transportation cost.
This method comprises the steps of making a reaction between natural gas and water at a temperature higher than the freezing point under a pressure higher than the atmospheric pressure to form the natural gas hydrate without freezing the water, physically dehydrating the thus formed natural gas hydrate, and during or after the physically dehydrating step, reacting the remaining water in the natural gas hydrate with natural gas to form natural gas hydrate to lower the water content of the resultant natural gas hydrate, chilling the resultant natural gas hydrate to a temperature lower than the freezing point to soak it in the remaining water (ice), and then making a pressure reduction.
IWASAKI SHOJIRO
ITO KATSUO
KONDO YUICHI
NAGAYASU HIROTSUGU
WATABE MASAHARU
EMA HARUHIKO
YOSHIKAWA KOZO