Treatment of municipal sludge by Fenton oxidation combined vacuum preloading.

Municipal sludge, composed of numerous types of organic matter with a gel structure, has high water content, low permeability coefficient, and poor mechanical properties. Fenton oxidation-assisted vacuum preloading method for municipal sludge treatment was proposed. First, the municipal sludge was oxidized and treated with Fenton's reagent; then, drainage consolidation was performed on the sludge with the vacuum preloading method. The optimal dosage of Fenton's reagent for municipal sludge was determined. Comparative experiments of the one-dimensional consolidation of municipal sludge treated with Fenton's reagent and the drainage consolidation by Fenton oxidation-assisted vacuum preloading were conducted. The results reveal that the specific resistance of municipal sludge decreases upon Fenton oxidation by approximately 98.6% at the optimal dosage of 22%, sludge water content decreases from 82.14 to 66.67%, volume reduces by ~ 40%, and unconfined compressive strength increases to 55 kPa.