14 / 2025-07-08 23:48:22

Deep Geological Storage of Unconventional Water Resources for Mitigating Disasters

Mine water,Deep geological storage,mine disaters

Mine water inrush may cause catastrophic disasters; however, it can be utilized as an unconventional water resource, especially in water-short areas. Since 2007, several deep geological storage test projects of mine water have been successively carried out in Muduchaideng Mine in Ordos, Nalinhe Mine NO.2, Laoyingyan Coal Mine in Sichuan, etc. in China.

At present, in Ordos, Inner Mongolia, the in-situ deep geological storage of mine water in the sandstone of the Liujiaogou Formation has been successfully carried out, and the mine water injection volume of a single well has exceeded 1.37 million cubic meters. In the high-intensively mining areas, Ordos, the recognition rate of the water-rich area in the roof is low, the storage capacity of the layer is small, and the recharge time is short. The combination of mine water resources (5 categories) and water storage target layers (8 types) can be classified into 22 hydrogeological structural types. We evaluate the structural units of the Ordos Basin based on storage capacity, sealing closure, and operability;  Combining the Analytic Hierarchy Process (AHP) with expert scoring to assign values to the evaluation index parameters, and classify the suitability levels of the Ordos Basin. The injection modes can be identified by considering the factors of TDS in mine water, the structural types of deep injection boreholes, the flow rate, the deep injection time and frequency, etc. The results show that the northern Shaanxi Slope is the most suitable tectonic unit, the Weibei Uplift is a moderately suitable area, and the Tianhuan Depression, Yimeng Uplift, and western Shanxi flexural fold belt are relatively suitable areas. According to storage capacity, impermeability and operability, 5 sets of strata suitable for injection have been screened out; the Ermaying, Heshanggou and Liujiaogou, Majiagou, and the Taiyuan Formations. Further challenges for the deep geological storage of unconventional water resources have been discussed, such as calculation method of hydrogeological parameters under fractured conditions, mechanism of multi-field coupling of  H-C-T fields.