农药中间体异氰酸甲酯生产废水预处理的研究

异氰酸甲酯生产废水COD的质量浓度为40 000～170000mg/L,采用热解、碱解、混凝、Fenton试剂氧化组合工艺对其进行预处理,考察最佳的工艺组合及反应条件。试验结果表明,对COD较高(原水COD的质量浓度为162000mg/L)、静置时间较长的废水采用热解、碱解及Fenton试剂处理后,COD总去除率可达70.37%;Fenton试剂处理的最佳反应条件为:pH值为3～4,质量分数30%的H2O2加入量为3.2%(体积分数),H2O2与Fe2+量比为5:1。

Pretreatment of wastewater from pesticide intermediate methyl isocyanate production

The mass concentration of COD in methyl isocyanate production wastewater was 40000-170000mg/L.Using pyrolysis,alkalinehydrolysis,coagulation and Fenton oxidation process to pretreat the said wastewater,the optimal process combination and reaction condition were investigated.The results of the test showed that,for the wastewater whichhadhigh COD concentration(mass concentration of COD in raw water was 162000mg/L) and a long staying time,the COD removal rate reached 70.37% after be treated by pyrolysis,alkalinehydrolysis and Fenton reagent.The optimal reaction condition for Fenton reagent was:pH value was 3-4,30%(mass fraction) H2O2 dosage was 3.2%(volume fraction),mass ratio of H2O2 to Fe2+ was 5:1.