Study On In-Situ Utilization Process Of Underground Mine Water Treatment

The conventional mine water treatment and utilization process is that mine water is usually raised to water treatment plant on the ground and after treatment, a part of water is utilized on the ground and the others returned back to underground as water resource. This method caused high promoting expenses of mine water, large covering area and greater capital investment. In view of the above questions, in-situ underground utilization process of mine water treatment was studied in the text, to achieve the rational utilization of mine worked-out section and mine water utilization.The experiments of the conventional mine water treatment process in the text were carried out taking coal slime making-up water of Xingtai mining area, without addition of coagulant and flocculant, in order to reduce underground mine water treatment equipments, simplify the operation process and reduce the labor intensity of the workers. The results show that, the free settling velocity0.4mm/s, the removal effeciancy of suspended solids (SS) is greater than80%after1hour settling; The inclined tube sedimentation with the surface load0.5～1.0mm/s at the raw water SS concentration about250mg/L, the SS removal effecaiancy is between50%～90%; the effect of quartz sand filter is best and influent turbidity10NTU, the effluent turbidity is less than1NTU; mine worked-out section remove SS mainly through filtration and sedimentation effect, and the effluent turbidity is less than10NTU with10m flow length for the protection; mine worked-out section�'filter and mine worked-out section�'inclined tube sedimentation�'filter process can effectively remove SS and reduce the effluent turbidity; free sedimentation�'inclined tube sedimentation�'filter process can be used without mine worked-out section.The process quartz sand and activated carbon filter�'reverse osmosis (RO) system is well for underground mine water with high salinity treatment. The tests show that RO desalination ability is efficient with the main cantions, the Ca2+、SO42-is more than98%, Cl-is more than96%and the system desalination removal efficiency is more than97%.Up-flow expansion filter neutralization process is suitable for in-situ underground acid mine water utilization and treatment, with effluent quality stable, without sencondary pollution, covering less area. The mine water pH value increases to more than6.5from2.0after stipping at flow rate less than60m/h. If neutralization reagent used, sodium hydroxide is for neutralize the acid mine water while higher water quality is required and spaces are limited; light burning magnesium powder can be used where rich in magnesite to achieve "treatment of wastes with process of wastes against one another" with good economic benefit and environmental benefit.Underground mine water treatment engineering practice show that using mine worked-out section�'compsite sedimentation�'filter process for the mine water with SS, the effluent quality is much better than the underground sprinkler standard; and using quartz sand and activated carbon filter�'reverse osmosis (RO) system, the effluent quality is much better than the"Emulsifying oil, concentrate and high-water content hydraulic fluid used for powered support and prop"(MT76-2002) standard.Because of the distinctiveness of the underground space, underground mine water treatment key technology includes safety drainage, underground space utilization, safety explosion-proof technology. According to the SS characteristics and concentration, multi-stage inclined tube settler and hydrolic automatic water filter were designed for underground mine water treatment.