Potential evaluation and development utilization technology of coalfield geothermal resources

Driven by the the carbon peak and neutrality goals, China will gradually reduce its dependence on fossil fuels such as coal and oil, and transform towards the development of clean, green, and low-carbon energy. In order to reasonably develop and utilize geothermal resources in mining areas, this article takes Jining Coalfield as the research object. Based on identifying the geothermal geological conditions in the coalfield area, the space freed up after coal mining and drainage is used as a "thermal reservoir". The geothermal resources and recoverable reserves of each mine are calculated using the thermal storage method and recovery rate method, and the potential for geothermal resource development and utilization is evaluated. The research results indicate that the geothermal resource reserves in Jining Coalfield are 1.05×1015KJ, equivalent to 36 million tons of standard coal; The recoverable heat reserve is 1.05 × 1014KJ, equivalent to 3.6 million tons of standard coal, which can reduce CO2 emissions by 8.59 million tons. The degree of geothermal development and utilization in coal fields is relatively low, and the development and utilization potential is large. Two technical solutions have been proposed for the utilization of heat energy from mine return air and waste heat from mine drainage in response to the summary of mining operations, Two geothermal utilization technology models have been proposed for closed pit mines, namely "heat extraction without water extraction" and "heat extraction without water consumption".Taking a typical coal mine as an example, combined with the development space of underground tunnels, the distribution characteristics of auxiliary shafts, filling holes, tunnel shafts, and straight discharge shafts, as well as mining facilities such as surface drainage pipelines and industrial square buildings, this paper elucidates the technology of geothermal development and utilization in coal fields. To provide technical support for the comprehensive utilization of geothermal energy in mines, green transformation of mines, and assistance in achieving the "dual carbon" goals.