Technical system and engineering application of geological deep well injection and storage of coal mine water

With the deepening of Beautiful China construction strategy and the comprehensive implementation of the “dual carbon” goal, the green and low-carbon transformation of energy has become a green engine driving the high-quality development of China’s economy. In the field of mineral resource development, the protection of mining ecological environment is facing a paradigm shift from end of pipe treatment to system restoration. The disposal of excess mine water generated by coal mining and high salt wastewater treated with reverse osmosis membranes has become the “last mile” problem in the current construction of green mines for the treatment of “liquid waste”. The technology of Geological Deep Well Injection and Storage (GDWIS) can use deep wells to inject fluids into the underground space of deep porous rock layers, utilizing the physical and chemical properties such as stability and sealing of deep geological environments to achieve isolation and disposal of fluids from the biosphere. Targeting the national deep scientific research and major technological needs of the coal industry, the current situation and problems of comprehensive utilization of mine water resources in China have been summarized, and the feasibility and technical ideas of using the technology of GDWIS to dispose of coal mine water have been elucidated. Based on the technical ideas, a technology system of GDWIS for mine water was proposed.Taking the M coal mine in the Ordos Basin as an example, systematic scientific research and technological applications have been carried out at the engineering scale. The research on GDWIS of mine water will be promoted to achieve scientific, safe, and controllable processes throughout the entire process, including “basic theoretical research, technical equipment development, system software development, and engineering practice application.” Finally, the innovative application directions for future deep geological storage technologies aimed at the “dual carbon” goal were proposed, including the coordinated storage of mine water and CO₂, and the storage of mine water accompanied by geothermal resource exploitation. This is of great significance for the safe mining and green mining construction of coal mines in the Ordos Basin of China, and will significantly promote scientific research and technological breakthroughs in the field of GDWIS of mine water in China.