The Application of Flat Ceramic Membrane in Mine Wastewater Treatment

The mine sewage is produced by washing the drill bit in the process of coal mining and the groundwater penetrating into the roadway in the process of coal mining. The mine sewage is collected to the sewage treatment station through the pipe network or underground ditch in the mining area. Therefore, it has the characteristics of groundwater, but due to man-made pollution, it also has some characteristics of surface water. The composition of mine sewage depends on the geological environment of coal formation and the mineral chemical composition of coal bearing strata. The mine sewage is yellowish brown with poor sensory properties. The main pollutants are suspended solids (SS) and iron in the water, which are typical inorganic wastewater. Suspended solids are mainly fine particles such as coal cuttings, rock powder and clay, especially pulverized coal, with a content of dozens to hundreds of mg / L, which is characterized by small particle size, light specific gravity and slow settling speed of suspended solids. According to statistics, for each ton of raw coal produced, the underground drainage is about 0.5m~10m, and the general drainage is about 3M

Combined with the actual situation of drainage, the system selects the water supply mode with different quality, and drill deep well water for domestic water in the mining area to ensure the safety of water quality. At the same time, the surface sewage treatment facilities will be moved to the underground for centralized treatment. After the treatment is qualified, some will be used for underground production and some will be lifted to the surface for industrial use in the factory area above the well. Considering the production conditions of the plant, in order to maximize the use of the original drainage system, it is finally decided to set up the sewage treatment station underground.

Due to the limited space of the original workshop and the advantages of ceramic flat membrane, such as large flux, small floor area, more stringent allowable inflow conditions, convenient operation, maintenance and management, a set of ceramic flat membrane device is installed underground for the disposal of underground sewage. Some abandoned tunnels that need to be reused underground are moderately transformed, and raw water tanks, filter membrane tanks and clean water tanks are built. The sewage produced by underground production first enters the raw water tank, and then enters the ceramic flat membrane tank. The gravity filtration method is used to produce water, which can meet the requirements of advanced treatment of discharge and reuse water.

Using this new sewage treatment mode, not only the construction volume is small, but also the operation cost is low. It can effectively replace the original surface sewage treatment facilities and achieve the energy conservation and emission reduction goals of mine construction, which plays a positive role in the protection of water resources in the mining area.