混凝沉淀法预处理种衣剂废水工艺优化

摘要

According to the characteristics of the seed coating wastewater(SCW)which has high chroma and high concentra-tion of organics,and through the analysis of the water quality,the coagulation process by using three kinds of co-agulants such as PAC,FeCl3and Al2(SO4)3was severally applied to treat SCW for improving its biodegradabil-ity.The Zeta potential,the removal efficiencies of COD and other indicators after treatment were evaluated.The results showed that the effect of PAC/PAM was favourable.During the best coagulation process(pH value of 8.0-9.0,PAC dosage of 1.5 g/L and PAM dosage of 1.5 mg/L), the removal efficiencies of COD and chroma were 81.7% and 56.3%, respectively. And the ratio of BOD5/COD was improved from 0.28 to 0.43, implying the biodegradability of SCW was improved.%针对种衣剂废水成分复杂、色度和有机物浓度高等问题,通过其水质分析确定采用混凝沉淀法预处理该废水,以提高其可生化性.处理后测定出水的Zeta 电位、COD 去除率等指标. 结果表明:在3 种混凝剂,如聚合氯化铝(PAC)、三氯化铁(FeCl3)和硫酸铝(Al2(SO4)3)中,PAC/PAM(聚丙烯酰胺)组合的混凝沉淀效果最佳,当调控pH 为8.0～9.0、PAC 用量为1.5 g/L 和PAM 用量为1.5 mg/L 时, 废水的COD 和色度去除率分别达到81.7%和56.3%,且出水的BOD5/COD 由0.28升至0.43,其生化性得到显著改善.