Experimental Study On Treatment Of Biochemical Effluent Of Leachate By Coagulation Fenton And Membrane Technology

Leachate will accumulate a large number of toxic and harmful substances with the time of the landfill.That makes the filtration liquid reduced.And the biochemical effluent is easy to block the membrane component,which can cause the burden of the treatment operation.Coagulation-Fenton has a stable treatment effect, a wide range of applications.It also will not produce toxic substances and affected by the outside influence.But as the main processing technology, coagulation-Fenton’s cost is higher.At present, it is generally considered as two separate processes in the combination of coagulation and Fenton treatment, but the content of iron in the coagulation process can promote the Fenton process.Therefore, this paper will be coagulation-Fenton as a process to deal with leachate biochemical effluent, determining coagulation-Fenton sequence and the best dosage of reagent range.Then the BBD experiment and response surface method are used to explore the influencing factors and the optimum operating conditions.Finally, using "ultrafiltration+reverse osmosis" and " coagulation-Fenton+reverse osmosis" to treat leachate biochemical effluent respectively.Through the analysis of reverse osmosis membrane flux, desalination rate, COD removal rate and turbidity removal rate in the evaluation of membrane fouling, determining the best economy combined process.Single factor experiment of coagulation-Fenton shows that the treatment effect of Fenton-coagulation is better and the treatment cost is higher than coagulation-Fenton. Combining with integrated benefit analysis, treatment of landfill leachate by coagulation-Fenton method is a better choice.Coagulation-Fenton response surface study shows that the fitting equation has high significance and sensitivity.The prediction error of COD removal rate is less than 5%.The primary and secondary effects of factors affecting the removal rate of COD are as follows:H2O2> n (H2O2) /n (Fe2+)> PFS.The optimal operating conditions are as follows:the PFS dosage of 1t landfill leachate is 3.33kg, the dosage of H2O2 is 5L, the dosage of FeSO47H2O is 6.89kg, the removal rate of COD can reach 92.11%."Ultrafiltration/coagulation Fenton+reverse osmosis" research shows that the reverse osmosis has better effect on the treatment of coagulation-Fenton effluent and ultrafiltration.COD, turbidity and desalination rate can reach75%, 95% and 50% respectively.However, the permeate flux decline rate and the concentration of COD in the coagulation Fenton effluent are less than that of the ultrafiltration.The removal rate of turbidity and the rate of desalination in the coagulation Fenton effluent are higher than that of ultrafiltration.Comprehensive comparative analysis, "coagulation Fenton+reverse osmosis" caused by membrane fouling to be significantly better than "ultrafiltration+reverse osmosis", cleaning costs are also relatively cheap.It is a combination process which can effectively reduce the membrane load.