Substantiation of technological solutions for the protection of water resources in the development of coal deposits

Abstract

Abstract In the case of mechanical treatment of mine water in settling tanks according to the existing technology the concentration of suspended solids during the discharge of clarified effluents into water bodies does not correspond to the maximum permissible content of mechanical impurities set for surface water bodies. The technology of mine water cleaning has been improved due to the introduction of a horizontal settling tank of modernized construction and installation of purification of fast open granular filters with downward liquid flow at the final stage. The expected technological parameters of the proposed horizontal settling tank for the conditions of water disposal of the operating coal mining enterprise are determined. The dependences between the depth of sedimentation of particles of the suspension of a certain hydraulic size in the proposed horizontal settling tank, its length and clarifying efficiency of mine water pre-treated with a solution of aluminium sulphate are obtained. It is established that the overall efficiency of clarifying of mine waters pumped to the surface by a coal mining enterprise, after treatment by the proposed technology will be 94-95% of the initial concentration of suspended solids, which does not exceed the relevant quality of surface water.