| In the research paper, the auther use four-combined integrated biological and physi-chemical treatment technology including Upflow Araerobic Sludge Blanket (UASB), Without Biomass Retention Sequential Batch Reactor (WSBR), Coagulation-flocculation and Electrolytic Oxidation to treaat the leachate from the retention basin of Linjiang municipal solid waste incineration power plant, Wenzhou. The research is in process to treat high-strength organic pollutant, ammonia, heavy metal and Cl- (COD=3940059150mg/L, NH3-N=380656 mg/L, pH=3.925.81) by the integrated treatment technology.Hydraulic retention time (HRT) and volumetric loading (VLD) have an obvious effect on the treatment by UASB. Gas production may reflect the result of the treatment and high volumetric gas production rate trends to effect the stabilization of the sludge in the reactor. The average volumetric COD removal efficiency, average volumetric gas production rate and average COD removal efficiency may respectively reach 5.13kgCOD/(m3·d), 2.75L/(L·d) and 90.1% in the condition that temperature, HRT and average VLR is respectively 30℃, 8d and 5.61kgCOD/(m3·d).HRT, temperature and aerobic time ratio have an obvious effect on the treatment by WSBR. The average volumetric TN removal efficiency, average volumetric NH3-N removal efficiency, average TN removal efficiency and average NH3-N removal efficiency may respectively reach 0.23kgNH3-N/(m3·d), 0.22kgNH3-N/(m3·d), 91.2% and 97.9 % in the condition that temperature, HRT, aerobic time ratio, average volumetric TN loading and average volumetric NH3-N loading is respectively 30℃, 4d, 0.33,0.25kgN/(m3·d) and 0.23kgNH3-N/(m3·d).In the coagulation-flocculation process, the combination of coagulants, coagulant dosage, pH, hydraulic condition and COD concentration in the influent have an obvious effect on the treatment by coagulation-flocculation. COD removal efficiency, color removal efficiency and turbidity may respectively reach 46.6%, 84.3% and 76.4% and COD concentration in the effluent may be reduced under500mg/L in the condition that the two-combined coagulant including 200mg/L PAFC and 500mg/L AS is at the same time put into the leachate adjusted pH to 6 with the rapid mix velocity of 300rpm, rapid mix time of 60s, reaction velocity of 50rpm, reaction time of 1 Omin and deposited at 30min.The study on electrolytic oxidation for leachate treatment shows that current density, electrolysis time, pH, distance between electrodes, Cl* concentration, temperature, ratio of electrode area to fiowrate and COD concentration in the influent have an obvious effect on the treatment by electrolytic oxidation. COD removal efficiency, NH3-N removal efficiency and color removal efficiency may respectively reach above 40%, near 100% and above 95% and COD concentration in the effluent may be reduced under 200mg/L in the condition that current density, electrolysis time, pH, distance between electrodes, Cl" concentration, temperature and ratio of electrode area to fiowrate is respectively 0.75A, 90min, 4, 5mm, 5000mg/L, 20 °C and 100cm2/L with the use of RuO2-IrO2-TiO2 / Ti electrode (SPR) as the anode.After treated by the four-combined treatment technology, COD may be reduced to under 300mg/L from above 50000mg/L, BOD5 may be reduced to near Omg/L from about 37000mg/L, NH3-N may be reduced to under 5mg/L from above 600mg/L, color may be reduced to under 10 times from above 8000 times, SS may be reduced to near Omg/L from above 8000mg/L and the heavy metal such as Zn, Cr, Cu and Pb may be almost removed completely. The effluent may meet Integrated Wastewater Discharge Standard II (GB8978-1996).The content of the paper is a part of the research of the Control Technology and Integrated Measurement for Treatment of leachate from Municipal Solid Waste Treated by MSWI, which is a secondary program of the Control Technology and Integrated Measurement for Treatment of Secondary Pollution from Municipal Solid Waste Incineration which is a predominant program in the environmental field of the National High Technology Research and Develop Program (863 Program).
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