煤矿矿井水零排放处理技术与应用

摘要

为了解决我国西部大型煤炭基地生产过程中面临的水资源紧缺及高矿化度矿井水零排放难题,对矿井水零排放工艺系统中的净化处理、深度处理、浓缩处理及蒸发结晶处理单元进行了技术研究与工程应用.结果表明,对于溶解性总固体TDS质量浓度≤5 000 mg/L的矿井水净化处理采用混凝澄清过滤工艺,深度处理采用苦咸水反渗透(BWRO)工艺,浓缩处理采用BWRO+碟管反渗透(DTRO)工艺,蒸发结晶采用多效蒸发(MED)工艺具有优势.采用上述工艺系统处理TDS质量浓度为1 900～2 400 mg/L的矿井水,浓缩处理后高浓盐水TDS质量浓度≥90 000 mg/L,系统回收率≥96.5％,最终出水TDS质量浓度≤300 mg/L;蒸发结晶单元分离出硫酸钠和氯化钠,满足工业盐标准要求,可作为化工原料利用;全系统综合运行费用约为7.89元/t水;整个工艺运行稳定,对水质变化耐受性好,处理效果佳.%In order to solve the problems of water resources shortage in the production process existing in the large-scale coal mine base of China's west and the problems of zero liquid discharge of mine drainage water with high mineralization,the technology system including purifying treatment,advanced treatment,concentrated treatment and evaporation crystallization treatment was researched and applied.The results showed that the technology system for mine drainage water with mass concentration of total dissolved sdids(TDS) ≤5 000 mg/L had advantages by using coagulation,purification and filtration for purifying treatment,using brackish water reverse osmosis (BWRO) for advanced treatment,using BWRO with disk tube reverse osmosis (DTRO) for concentrated treatment,and using multiple effect distillation (MED) for evaporation crystallization treatment.Adopted the technology above to treat mine drainage water with TDS mass concentration 1 900 ～ 2 400 mg/L,the water quality could be achieved TDS mass concentration ≥ 90 000 mg/L of high-concentrated saline water,system water recovery ≥96.5％ of whole systems and TDS mass concentration ≤300 mg/L of last effluent.Sodium chloride and sodium sulfate separated from evaporation crystallization could be met the standards of industry salt,and could be used as raw materials for chemical industry.The whole technology system with 7.89 RMB/t of integrated operating cost had advantages of stable operation,good tolerability for change of water quality and satisfying treatment effects.