Progress and typical case analysis of demonstration projects of the geological sequestration and utilization of CO₂

The implementation of the geological sequestration and utilization of CO₂ (CGSU) has considerable effects on CO₂ emission reduction and is of great significance for the mitigation of global warming and the execution of the sustainable development strategy in China. Therefore, this study sorted the major methods for CGSU, made statistics of the global demonstration projects of CGSU, and primarily introduced the typical demonstration projects of CGSU in China. Furthermore, this study proposed prospects for the development trend of the CGSU technologies, which primarily include CO₂ enhanced oil recovery (CO₂-EOR), CO₂ enhanced coalbed methane recovery (CO₂-ECBM), CO₂ enhanced saline water recovery (CO₂-ESWR), CO₂ enhanced nature gas recovery (CO₂-ENGR), CO₂ enhanced shale gas recovery (CO₂-ESGR), CO₂ enhanced geothermal power generation (CO₂-EGP), and CO₂-based in-situ leaching of uranium (CO₂-ILU) at present. Among them, CO₂-EOR, CO₂-ESWR, and CO₂-ILU have been widely and commercially applied at home and abroad due to their complete technical systems, while other methods of CGSU are still in the stage of field tests and engineering exploration. A total of 23 CGSU projects have been implemented in China, including 12 CO₂-EOR projects, two CO₂-ESWR projects, seven CO₂-ECBM projects, and two CO₂-ILU projects. The CGSU technology in China started late and still lags behind that of developed countries in Europe and the USA. There is an urgent need to accelerate the construction of demonstration projects of the whole process technology and cluster deployment of CGSU with a scale of more than 1 million tons/year and enhance the basic science research on the technology and cluster deployment of CGSU in the future. The main purpose is to solve the bottlenecks in the critical links of the whole-process technology of CGSU.