偶氮染料印染废水预处理方法的比较研究

Comparative study of the pretreatment of azo printing and dyeing wastewater

为解决湖北某厂以偶氮染料为主的碱性印染废水可生化性差、色度高、COD高等问题,采用絮凝、Fenton试剂和臭氧氧化的预处理方法对其进行处理,比较了3种方法的处理效果。结果表明:3种方法中,臭氧氧化预处理效果最好,但处理成本太高;硫酸亚铁和聚合硫酸铁复合使用时,于100 mL印染废水中投加0.05 g硫酸亚铁和1.00 mL 8%聚合硫酸铁,COD去除率达49.35%,色度去除率为87.50%,B/C升高至0.34,效果次之;Fenton试剂预处理,效果最差。综合考虑,适合此废水的预处理方法为硫酸亚铁和聚合硫酸铁复合使用的絮凝法。

The alkaline wastewater, mainly azo dyes, in a plant in Hubei Province,is characterized by poor biodegra- dability, high chroma, and high COD. In order to solve these problems, some pretreatment methods, such as coagula- tion, Fenton reagent, and ozone oxidation have been used. The results show that among the three methods, the pre- treatment efficiency of ozone oxidation method is the best, but its treatment cost is too high. When ferrous sulphate and poly-ferrous sulphate are used complexly,with 100 mL dyeing and printing wastewater,the dosages of ferrous sulphate is 0.05 g and 8% of poly-ferrous sulphate 1.00 mL, the COD removing rate reaches 49.35%, chroma remov- ing rate 87.50%, B/C is increased to 0.34, the efficacy is next to the best. The efficacy by using Fenton reagent is the worst. Taking all factors into consideration, the pretreatment method which is suitable for this wastewater is the co- agulation which uses ferrous sulphate and poly-ferrous sulphate complexly.