GAS-HYDRATE RECOVERY SYSTEM, AND RECOVERY METHOD THEREOF

PROBLEM TO BE SOLVED: To provide a gas-hydrate recovery system and a recovery method thereof for recovering a gas-hydrate lump, while suppressing clogging of a transport channel for transporting the gas-hydrate from a water bottom toward a water surface, the clogging being caused by adhesion of re-hydrated raw material gas, which has dissolved in water, on an inner wall surface of the transport channel.SOLUTION: A transport channel is for transporting a gas-hydrate lump m collected by excavating a water bottom 2, the gas-hydrate lump m being transported toward a water surface along with water in which raw material gas g that constitutes the gas-hydrate has dissolved, and water w having a source gas concentration lower than the source gas concentration of the water passing through the transport channel is supplied into the transport channel from a plurality of locations midway the transport channel.SELECTED DRAWING: Figure 1 【課題】水底から水上に向かってガスハイドレートを搬送する搬送経路の途中で、水中に溶解した原料ガスが再ハイドレート化して搬送経路の内壁面に付着して搬送経路が閉塞されることを抑制しつつ、塊状のガスハイドレートを回収するガスハイドレート回収システムおよびその回収方法を提供する。【解決手段】水底２を掘削して塊状のガスハイドレートｍを捕集して、ガスハイドレートを構成する原料ガスｇが溶解した水とともに塊状のガスハイドレートｍを水上に搬送する搬送経路の途中の複数地点で、この搬送経路を通過する水の原料ガス濃度と比べて原料ガス濃度が低い水ｗを搬送経路内に供給する。【選択図】図１