Simulation test on treatment of landfill leachate by coagulation-UV-photocatalysis-fenton-oxidation process

The treatment efficiency of coagulation-UV-Fenton reagent method on treating landfill leachate containing non biodegradable organic contaminants was studied.The effects of pH,dosage of PAC,dosage of PAM,stirring intensity,dosage of Fe2+,molar ratio of H2O2/Fe2+ and reaction time on CODcrclearance rate were investigated.The result shows that the optimal state of PAM dosage=5 mg·L-1,the dosage of PAC=800 mg·L-1,pH=5,stirring intensity=200 r·min-1;pH=3,the dosage of Fe2+=0.01 mol·L-1,nH2O2/nFe2+=10 ∶1,reaction time=60 min.These seven factors have significant impacts on the treatment efficiency of CODcr.In case the influent CODcr concentration is 3 500 mg·L-1,after these treatment processes,the effluent CODcr concentration is 82.95 mg·L-1,the removal rate of CODcr is 97.6%,chemical costs 2.25 yuan/t.This process is suitable for small town landfill leachate treatment.