典型混凝剂对汽车水性漆喷涂清洗废水超滤后浓缩液的处理效果

Treatment Effect of Typical Coagulants on Concentrated Solution after Ultrafiltration of Automobile Waterborne Paint Spray Cleaning Wastewater

为了达到减排增效的目的,通过对比CaCl_(2)、NaCl、CaSO_(4)3种无机混凝剂对4种汽车水性漆喷涂清洗废水超滤后浓缩液的处理效果,研究了混凝处理条件。结果表明:CaCl_(2)对清洗废水浓缩液具有较好的处理效果,混凝静置沉淀的最佳时间为30 min,其最佳投加量与形成废水时所用清洗溶剂类型有关,对含清洗溶剂1和清洗溶剂2的废水浓缩液而言,CaCl_(2)的最佳投加量分别为8%和2.5%,处理后上清液产出率为64%~93%,COD下降比例为43.2%~62.3%。

In order to reduce emission and increase benefit,the treatment effects of CaCl_(2),NaCl and CaSO_(4)on 4 kinds of concentrated solution after ultrafiltration of automobile waterborne paint cleaning wastewater were studied to obtain coagulation treatment conditions.The results show that CaCl_(2)has a good treatment effect on the concentrated solution of cleaning wastewater.The optimum time for sedimentation after coagulation is 30 min.The optimum dosage of CaCl_(2)depends on the type of cleaning solvent used to form the wastewater.For concentrated wastewater containing cleaning solvent 1 and 2,the optimum dosage of CaCl_(2)was 8%and 2.5%,respectively.After treatment,the supernatant production rate was 64%to 93%and COD decreased by 43.2%to 62.3%.