The status and development trend of in-situ conversion and drilling exploitation technology for oil shale

Abstract:

China has abundant oil shale which is a potential oil and gas resource and important strategic resource to ensure national energy security. In-situ exploitation is the development trend of the oil shale industry. Through a systematic data collection and investigation， the development process of oil shale in-situ exploitation technology is summarized. The main technical characteristics and development status of four kinds of heating technologies， including conduction heating， convection heating， radiation heating and reaction heating technologies， and five kinds of reservoir reconstruction technologies， including hydraulic fracturing， underground blasting， freezing wall， grouting curtain and gas injection barrier underground space sealing technologies， are further analyzed. According to the characteristics of China’s oil shale resources， three key technologies that must be broken through and adopted for the in-situ exploitation of oil shale are proposed. The first is the high-efficiency heating technology with multiple heating， high efficiency downhole heater and catalytic efficiency as the core. The second is the horizontal well steering drilling technology with rotary steering drilling and precise distance measurement guiding for dual well as the keys. And the third is the composite reservoir reconstruction technology with CO₂ dry fracturing， acid fracturing and gas injection barrier underground space sealing technologies. It is hope that this work could provide some reference for the in-situ exploitation technology of oil shale in China.