PNEUMATIC FRACTURE METHOD AND EQUIPMENT FOR SHALE GAS EXPLOITATION

摘要

A pneumatic fracture method for shale gas exploitation: repeatedly and alternately applying compressed high temperature gases of at least two different pressures on a shale rock stratum until the shale rock stratum forms a crack structure, the compressed high temperature gases having a temperature of at least 80°C, a maximum pressure of at least 25 MPa, and a minimum pressure being 1/4-1/3 of the maximum pressure. In the above method, the compressed high temperature gas is preferably compressed high temperature air or compressed high temperature carbon dioxide gas. When the compressed high temperature gas is compressed high temperature air, the temperature thereof is at least 150°C, and the maximum pressure thereof is at least 45 MPa; and when the compressed high temperature gas is compressed high temperature carbon dioxide gas, the temperature thereof is at least 80°C, and the maximum pressure thereof is at least 25 MPa.