Compressed gas storage tank utilizing rock-bed cavity

Abstract

A compressed gas storage tank 10 utilizes a rock-bed cavity 11 in which a bentonite slurry is fed into an underground cavity 11 formed in a rock-bed, a forcibly fed compressed gas is stored in the rock-bed cavity in a state in which the compressed gas is loaded with a pressure load of the bentonite slurry from the underside of the compressed gas, the bentonite slurry in the rock-bed cavity 11 is of a dual layer structure consisting of an upper layer composed of a light bentonite slurry 30 mixed with a filling-up material invading into and filling up a void and a crack formed in an inner wall surface of the rock-bed cavity and a lower layer composed of a heavy bentonite slurry 13 mixed with a high specific gravity fine powder as a load condition material. The filling-up effect of the bentonite slurry secures sufficient liquid-tightness and air-tightness in the ceiling part of the rock-bed cavity, making it possible to efficiently and economically store compressed gases such as compressed air or natural gas without allowing them to escape.

Dependencies are inferred from the claim text.