Research on the treatment of main pollutants and environmental protection in a mine in Inner Mongolia

A large uranium deposit in Inner Mongolia adopts CO₂+O₂ in-situ leaching technology. CO₂+O₂ is used as leaching agent to prepare leaching solution, which reacts with uranium in the ore layer to form ions. Drilling waste well fluid and process wastewater pollutants are generated during the leaching and hydrometallurgical treatment of leaching solution at the well site. In the process of treating pollutants, the waste well fluid is treated by cementing, surface solidification and recovery. The resin transformation wastewater is treated by reverse osmosis, and the reverse osmosis concentrated water and resin recoil wastewater are discharged to the evaporation tank for evaporation. The results show that the radioactivity of the drilling waste well fluid is low, the average concentration of natural uranium is 38 mg/L, and the average activity concentration of ²²⁶Ra is 79 Bq/L. After resin transformed water reverse osmosis treatment, the concentration of natural uranium <0.05 mg/L, the activity concentration of ²²⁶Ra<1.1 Bq/L. The average secific activity of natural uranium activity is 426.90 Bq/L, and the average specific activity of ²²⁶Ra is 696.67 Bq/kg in evaporation pond residue. Through the treatment of pollutants, the cementing and surface curing meet the environmental requirements, and the process wastewater and evaporation pond residue meets relevant standard requirements, the methods and ideas for the treatment of this type of mine pollutants are provided. The method described in this paper can achieve the purpose of pollution control, protect the local ecological environment, produce positive corporate and social benefits, and provide a guarantee for the high-quality development of enterprises.