化学混凝法处理酸洗磷化综合废水的研究

Treatment of acid-washing phosphatizing wastewater by chemical coagulation method

为了确定适用于酸洗磷化废水的混凝剂及相应的最佳操作条件,以COD为主要考察指标,进行了一系列混凝试验。结果表明,在所选取的混凝剂中,氯化亚铁对试验原水的混凝效果最好,进一步试验确定的最佳操作条件为:氯化亚铁投加量为200mg/L,pH值为7.0,快速搅拌(搅拌强度300r/min)1min,慢速搅拌(搅拌强度90r/min)15min,沉降1h,此时,废水中COD的去除率可以达到40%。

In order to find a proper coagulant for acid-washing phosphatizing wastewater treatment and determine its optimal operation condition, a series of coagulation tests with COD as the main investigation index were carried out. The results showed that, ferrous chloride has the best coagulation performance compared with the other seclected coagulants, the optimal operation condition was determined as follows： the dosage of ferrous chloride was 200 mg/L, the pH value was 7.0, the high speed agitation（agitation intensity was 300 r/min） time was 1 minutes, the low speed agitation （agitation intensity was 90 r/min） time was 15 minutes, and the sedimentation time was 1 h. Under the above condition, the COD removal rate could reach 40%.