Abstract:Ensuring national energy security and achieving the strategic objective of “carbon peaking and carbon neutrality” can be facilitated by utilizing mining resources to construct underground storage. Determining the storage capacity of the subterranean reservoir and guaranteeing the stability and safety of the energy storage system need an understanding of the permeability properties of coal and rock layers in the mines storage area. Based on the concentrated brine underground storage project of Lingxin Coal Mine, this paper carried out an in-situ water injection test to study the permeability characteristics of coal and rock in the mining area, and investigate the permeability characteristics and water permeability of the remaining coal pillars, the top and the low plates of coal seams. The test findings indicate that the top plate of coals 15 and 16 has a stable flow rate of 1.76~8.82L/min, the bottom plate of coals 16 has a steady infiltration volume of 1.971.76~8.82L/min, and the stable flow value of the heritage coal pillar of each seam is 1.0~6.12L/min. On this basis, the permeability of the coal pillar in each seam is calculated to be 0.046~0.261Lu, that of the top plate to be 0.07~0.162Lu, and that of the bottom plate to be 0.042Lu. The permeability of the coal pillar in the 16 coal seams is the biggest, measuring 0.261Lu. Overall, coal and rock formations have poor water permeability, which is conducive to the construction of underground storage projects. Relevant research provides a foundation for the design and operation of underground storage.
