生化-调碱后垃圾渗滤液的Fenton深度处理效果

针对上海老港垃圾填埋场经过厌氧-曝气塘处理后的渗滤液难进一步处理的问题,对其采用厌氧滤池-好氧接触法、氧化钙2种方式预处理,在此预处理基础上,考察了Fenton法深度处理的效果,探讨了H2O2/Fe2+投加比、初始pH、H2O2投加量、反应时间和Fenton试剂投加方式对渗滤液COD去除效果的影响。研究发现:经过生物预处理后,渗滤液的COD和TP分别降低了24%和25%;氧化钙调碱可以进一步使COD和TP去除率分别达到42%和96%;后续Fenton深度氧化的最佳条件为:初始pH为2,H2O2投加量为2.4 g/L,H2O2/Fe2+摩尔比为5∶1,Fenton试剂一次投加,反应时间为2 h。在此条件下,渗滤液的COD从1 340 mg/L降到198 mg/L,总COD去除率达到85%。

Effect of Fenton process on leachate pre-treated by biological process and pH regulation

Leachate from Laogang Refuse Landfill was processed by Fenton reagent after it was pre-treated by anaerobic filter and aerobic biological process and pH regulation with CaO in this work.It was found that COD and TP could be removed by 24%and 25%,respectively after leachate was pre-treated by anaerobic filter/aerobic biological process,and the removal rate of COD and TP could be further increased to 42%and 96%,respectively after the pH value of leachate was adjusted to 12 using CaO.Then,Fenton process was introduced to remove the remained pollutant in leachate,and the effect of molar ratio of Fe~(2+)and H_2O_2,pH,H_2O_2 dosage,reaction time and feeding mode on COD removal efficiency were investigated.Results showed that the optimum operation conditions were pH of 2,H_2O_2/Fe~(2+)of 5:1 (molar ratio),H_2O_2 dosage of 2.4 g/L and the reaction time of 2 h.Under the above conditions,the COD of leachate was reduced from 1340 mg/L to 198 mg/L,with a total removal rate of 85%.