Heavy metal removal and dewaterability enhancement by optimum Fenton’s reagent from urban anaerobically digested sludge

Abstract

Sludge dewaterability is pointed out as a major expensive part of water treatment systems. In this study, Fenton reaction is applied for treating the anaerobically digested sludge. In the first section, we studied the impact of oxidation process on sludge dewaterability. Here, raw sludge dewaterability has improved by using different concentrations of H2O2 and Fe2+ (1:1, 1:10 and 1:100 ratio). Batch experiments were adjusted to 1% and 5% of total suspended solids (TSS). The result of this thesis indicated that about 88% CST was reduced by using 1:1 and 1:100 ratios of H2O2 and Fe2+. Significant results were observed after one-hour oxidation period for heavy metal extraction like Cd, Cu, Pb and Zn that were taken out from the raw sludge. So, it can be proposed that adding Fenton’s reagents may improve the sludge dewaterability quality.