“微滤+反渗透”工艺在处理垃圾渗滤液中的应用研究

Research and Application of Landfill Leachate Treatment Based on Technology of Microfiltration and Reverse Osmosis

采用＂多孔陶瓷微滤＋两级反渗透＂工艺处理垃圾渗滤液。分别考察多孔陶瓷微滤膜、一级反渗透和二级反渗透对渗滤液COD、NH3-N、电导率及相应去除率与运行时间的关系,还重点考察了一级反渗透系统回收率控制及清洗周期和方法。研究结果表明：经过陶瓷微滤预处理后,出水的COD、NH3-N去除率、脱盐率分别维持在50.3%、30.2%、30.1%以上;经过一级反渗透处理后,出水的COD、NH3-N去除率、脱盐率分别维持在94.8%、91.3%、81.6%以上;经过二级反渗透处理后,出水的COD、NH3-N去除率、脱盐率分别维持在80.1%、81.3%、85.1%以上。＂多孔陶瓷微滤＋两级反渗透＂工艺处理垃圾渗滤液出水的COD〈30 mg/L,NH3-N〈25 mg/L,电导率〈180μm/cm,达到《生活垃圾填埋污染控制标准》（GB16889-2008）。一级反渗透系统清洗周期为400min,回收率控制在65%~70%,先碱洗后酸洗的方法更有利于反渗透膜通量的恢复,膜通量可恢复到新膜渗透通量的95%。

Landfill leachate was treated by the process of porous ceramic microfiltration membrane and two steps reverse osmosis,and the relationship between removal rate of COD,NH3-N,electrical conductivity and operating time in porous ceramic microfiltration membrane,one-stage RO and two-stage RO were investigated,the study also focused on the recovery rate of one-stage reverse osmosis system control and cleaning cycles and methods.Results indicated that after ceramic microfiltration pretreatment,the effluent removal rate of COD,NH3-N and desalination rate remained above 50.3%,30.2% and 30.1% respectively.Through one-stage reverse osmosis treatment,the effluent removal rate of COD,NH3-N and desalination rate remained above 94.8%,91.3% and 81.6% respectively.Through two-stage reverse osmosis treatment,the effluent removal rate of COD,NH3-N and desalination rate remained above 80.1%,81.3% and 85.1% respectively.After the process of porous ceramic microfiltration and two steps reverse osmosis,COD,NH3-N and conductivity of the effluent water of landfill leachate was below 30 mg/L,25 mg/L and 180 μm/cm respectively,with effluent quality satisfactory to MSW Landfill Pollution Control Standard of GB16889-2008.One-stage reverse osmosis system cleaning cycle is 400min,recovery rate should be controlled at 65%～70%,the union of alkali washing and acid pickling is more conductive to reverse osmosis membrane flux recovery.The flux of membrane can be restored to 95% of the flux of the new membrane.