强化3级Fenton氧化结合石灰乳中和混凝处理苯系染料中间体废水

Treatment of benzene series dye intermediate wastewater by enhanced three-staged Fenton oxidation combined with lime milk neutralization coagulation

采用多级Fenton氧化结合石灰乳中和混凝对苯系染料中间体废水进行强化处理,考察了Fenton试剂投加级数和投加比例对废水处理效果的影响,以及多级Fenton氧化之间石灰乳中和混凝作用效果,并分析了废水中有机成分的变化趋势。结果表明:Fenton氧化过程中,COD去除率随着Fenton试剂投加级数的增加逐渐增大,3级时效果最佳。3级Fenton处理过程中,Fenton试剂的投加比例为1∶2∶3时,COD去除率最高。在Fenton试剂投加比例为1∶2∶3的3级Fenton氧化过程中,石灰乳可有效调节pH由2.5至4.0,同时其混凝作用也可进一步提高COD去除率,最终COD去除率可达97.20%。经GC-MS对各个过程中有机物的分析鉴定,可发现原废水中的苯系有机物逐渐变化为苯酚、对苯醌以及短链小分子脂肪酸等物质。

Multi-staged Fenton oxidation combined with lime milk neutralization coagulation was used to intensi- fy the treatment of benzene series dye intermediate wastewater. The effects of Fenton reagent addition stages, do- sing ratio and the lime milk neutralization and coagulation stages between multi-stage Fenton oxidation on wastewater treatment were investigated. Furthermore, the variation trend of organic components in wastewater was analyzed. The results indicated that the COD removal rate increased gradually with the stage addition of Fenton reagent in the process of Fenton oxidation, and the best effect occurred at the three stage. In the three-staged Fenton treatment, the COD removal rate was highest at the Fenton reagent ratio of 1 ： 2 ： 3. In the three-staged Fenton oxidation with the addition rate 1 ： 2 ： 3, the lime milk could adjust pH from 2.5 to 4. 13 effectively. Meanwhile, coagulation could further improve the COD removal rate. The final removal rate of COD was up to 97.20%. Through the analysis and identification of organic compounds in each process by GC-MS, it could be found that the benzene series organic compounds in the original wastewater gradually changed into phenol, p- benzoquinone, and short chain small molecular fatty acids and so on.