反渗透处理高盐化工废水的试验研究

Study on high salinity chemical wastewater treatment by reverse osmosis

以经过两级混凝-超滤预处理后的化工废水为研究对象,通过试验考察了反渗透脱盐工艺处理高盐废水的效果和工艺稳定性。通过反渗透脱盐率和膜通量的变化来判定运行条件和进水水质对膜性能的影响。结果表明：系统稳定运行后对COD、电导率的平均去除率分别为94.38%、98.20%。在恒定压力（0.85 MPa）下,当进水TDS为3 500 mg/L时,膜性能稳定,膜通量衰减速率为0.008 6 L/（m2.h）,在进水TDS〉4 500 mg/L时脱盐率与膜通量随进水浓度的增大急剧下降。阻垢剂投加量为3.0~4.0 mg/L时,系统稳定运行150 h内压差稳定在0.04~0.07 MPa,出水满足该厂部分工艺用水的水质标准。

Taking the chemical wastewater treated by two phase coagulation-ultrafiltration as research object,the stability and effect of reverse osmosis desalination process were investigated in the test.The membrane properties influenced by operating conditions and wastewater quality were judged through desalination rate and permeation flux.The results showed that after the stable operation of the process the average removal rate of COD and conductivity was 94.38% and 98.20% respectively.At a constant pressure（0.85 MPa）,when influent TDS was 3500mg/L,the membrane operating properties were steady and flux decay rate was 0.0086L/（m2·h）,while desalination rate and permeation flux declined sharply with influent concentration increasing as TDS 4500mg/L.The input of inhibitor dosage was 3.0~4.0mg/L,the pressure difference was stable at 0.04 ~ 0.07MPa and system stable operation in 150h,the effluent was partly met the water quality criteria of process water.