The Effect Of Fenton Treatment And Coagulation On COD Removal Efficiency In The Landfill Leachate Sample

Landfill leachate is a high strength organic wastewater originating from the dumping, transfering, landfilling of solid wastes, which can pollute waters severely. In recent years, the treatment of landfill leachate increasingly draws attention of people. Among the various method to treat with landfill leachate, physico-chemical method is widely investegated and used because of its advantages such as the steady effect, the wide application, the good effect to treat with low biodegradable landfill leachate. Among the various physico-chemical treatments, Fenton treatment and coagulation are investigated and used commonly.In this paper, we took the landfill leachate from a waste trasfer station in Ningbo as our sample, and used Fenton treatment and coagulation to treat with the sample, thus determined the optimized resolution to deal with the landfill leachate. The major contents are described as follows:(1) The factors affecting coagulation were investigated. PAM and PAC were used as coagulants and determined the optimum conditions for coagulation: the concentrations of PAM and PAC were 6 mg.L^-1and 800 mg.L^-1, respectively, the coagulation time was 4 h, and pH value was 10.(2) The effect of COD removal by Fenton treatment and coagulation to treat with landfill leachate was investigated, and promoted the optimum resolution: first apply Fenton treatment, and then coagulation. The optimum conditions for Fenton treatment were: the concentrations of FeSO₄ and H₂O₂ were 8 g.L^-1 and 3.2 mL.L^-1, respectively, the time was 4h and pH value was 3. The optimum conditions for coagulation: the concentrations of PAM and PAC were 6mg.L^-1and 800mg.L^-1, respectively, the coagulation time was 4h, and pH value was 10.