Abstract:
A device for constructing an underground reservoir by dissolving limestone using carbon dioxide. The device includes a CO2 storage tank; an absorption tower; a decompression valve; a gas-liquid separator; a crystallizer; a vacuum pump; a buffer tank; a first booster pump; a second booster pump; and a third booster pump. The decompression valve is connected to a limestone layer, and is connected to the gas-liquid separator. The absorption tower is connected between the gas-liquid separator and the limestone layer.
Abstract:
A pneumatic fracturing method for exploiting shale gas, the method including: 1) applying a compressed gas for a first period of time at a first pressure to a shale formation; 2) applying the compressed gas for a second period of time at a second pressure to the shale formation; and 3) repeating steps 1) and 2) to produce fissures in the shale formation. A temperature of the compressed gas is at least 80° C. A maximum pressure of the compressed gas is at least 25 megapascal, and a minimum pressure of the compressed gas is between ¼ and ⅓ of the maximum pressure.