| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to suppress a riser tube from being clogged because of freezing of sea water or lake water when a gas is generated in the riser tube, and collect methane hydrate efficiently with small energy.SOLUTION: A methane hydrate collection system comprises: a riser tube 2 for transferring slurry obtained by mixing methane hydrate existing a sea bottom or lake bottom, or below them and sea water or lake water, onto the sea or lake; and heating means 11 for heating the slurry in the riser tube 2 by using surface layer water of the sea or lake as a heat source. The methane hydrate collection system: generates an upward flow of the slurry in the riser tube by using a gas lift effect of a gas generated by decomposition of the methane hydrate when the methane hydrate in the slurry is decompressed to cause self-melting of the methane hydrate during rise through the riser tube; and suppresses sea water or lake water in the slurry from freezing, by using heat supplied from the heating means. |
