闭坑煤矿山酸性废水治理方法:以贵州省道真县平模山闭坑煤矿为例

Treatment method of acid wastewater in closed pit coal mine:a case study of Pingmoshan Closed Pit Coal Mine in Daozhen County of Guizhou Province

以贵州省道真县平模山闭坑煤矿为例,探索适宜于岩溶山区闭坑煤矿山酸性废水(ADM)治理的实用技术,为岩溶山区开展闭坑煤矿山酸性废水治理工程提供参考。综合分析矿区地表水和地下水补、径、排关系,以及酸性废水量、水质情况,采用主动处理和被动处理相结合的方法,通过清污分流工程+酸性废水净化提升工程+人工湿地净化工程+复垦工程+附属工程进行综合治理。工程竣工后取治理区域末端水样进行检测分析,治理区域末端水质pH值为6.42,硫酸根离子(SO_(4)^(2-))浓度为248 mg/L,铁离子(Fe)浓度为5.42 mg/L,锰离子(Mn)浓度为3.28 mg/L,悬浮物浓度为46.64 mg/L,研究结果表明:5个重要监测指标pH值、硫酸根离子、铁离子、锰离子、悬浮物浓度均低于《煤炭工业污染物排放标准》(GB 20426—2006)排放标准,治理效果较为显著。在有效改善矿区生态环境的同时,新增耕地面积4800 m^(2),新增植被恢复面积918 m^(2),流域保护长度9.8 km。研究结论可为岩溶山区废弃闭坑煤矿山酸性废水治理提供技术可行、经济合理的治理模式参考。

A case study of Pingmoshan Closed Pit Coal Mine in Daozhen County of Guizhou Province,to explore the practical technology suitable for the treatment of acid wastewater(ADM)from closed pit coal mine in karst mountainous area,and to provide reference for the acid wastewater treatment project from closed pit coal mine in karst mountainous area.The relationship of surface water and groundwater recharge,drainage and discharge as well as the quantity and quality of acid wastewater in the mining area are comprehensively analyzed.The method of combining active treatment and passive treatment is adopted to carry out comprehensive treatment through sewage diversion project,acid wastewater purification and upgrading project,constructed wetland purification project,reclamation project and auxiliary project.After the completion of the project,the water samples at the end of the treatment area are tested and analyzed.The results show that the pH value of the water at the end of the treatment area is 6.42,the concentration of sulfate ion(SO_(4)^(2-))is 248 mg/L,the concentration of iron ion(Fe)is 5.42 mg/L,and the concentration of manganese ion(Mn)is 3.28 mg/L.The concentration of suspended matter is 46.64 mg/L,and the results show that the 5 important monitoring indicators pH value,sulfate ion,iron ion,manganese ion and suspended matter concentration are all lower than the emission standard of Coal Industry Pollutant Discharge Standard(GB 20426—2006),and the treatment effect is relatively significant.While effectively improving the ecological environment of the mining area,the cultivated land area is increased by 4800 m^(2),the vegetation restoration area is increased by 918 m^(2),and the basin protection length is 9.8 km.The research results can provide a technically feasible and economically reasonable treatment model for acid wastewater treatment of abandoned closed pit coal mine in karst mountainous areas.