| The characteristics of analogy recycling semi-aerobic landfill leachate is that the COD concentration and the ammonia-N concentration are low, the biodegradability is poor, the degree of mineralization is great, it manily express that the chlorine ion concentration is great. Base on the leachate characteristics,in the lab test range, mainly study the influence of anode material on the treatment result,study the conversation of chlorine ion during the electrolytic treatment,study the electrolytic oxidation kinetics of inhibition biodegradation or toxic organic matters in the chlorine ion regime . The relationship between the biodegradability of leachate and the the molecular weight distribution of dissolved organic matters is also discussed preliminarily. Contrast study the technological condition and the treatment result which use electrolytic technology as full-treatment and pre-treatment for this leachate.Provided a theoretic base and. technical parameters for the application of electrochemical technology to treat for inhibition biodegradation organic wastewater.The influence of anode material on the result of electrolytic treatment is discussed for leachate from lab test. It shows that (1)when useβ-PbO2 anode to electrolytic treat for the leachate, the oxidation -reduction reaction rate of electrolyte and electro-catalytic permormance is the greatest, the current of anode is the greatest, (2)if the anode material is different ,the removal result of every index is also different .when use Ru-Ir/Ti anode to electrolytic leachate, it can accelerate the Cl-to oxidize into ClO- which can produce indirect oxidation to accelerate the degradation of organic, so the COD removal result is the best. When treat the leachate concluding the little Cl-, to use theβ-PbO2 anode is suitble.(3) the trend of the molecular weight distribution is different if the anode material is different. When useβ-PbO2 anode, with increasing the electrolytic time, the radio of all kinds of organic matters change little; when separately use Ru-Ir/Ti anode and MMO anode ,the radio of organic matters that molecular weight are below 2×103u can increase from 67.6% to 76.6% and 87.2% separately.The chlorine ion functions during the electrolytic treatment leachate discusses from three spheres that is the function of chlorine, the morphological conversion of chlorine ion and the electrolytic oxidation characteristics of typical organic matters. The experiment result shows that(1)when the initial chloride ion concentration in the leachate is in 0-12. 5g/L, the removal load of organic matters increase with increasing the initial chloride ion concentration in the leachate. If the initial chloride ion concentration was over 12.5g/L and the electrolytic time is longer, the influence degree of initial chloride ion concentration is little. When treats high concentration leachate, the influence degree of initial chloride ion concentration on the removal load of organic matters is greater. (2) in the electrolytic test condition, the mainly morphological of chloride ion was mainly Cl-, residual chloride and Cl2, the average content of Cl- morphological and residual chloride morphological is 85.8% and the average content of Cl2 which gave out from the leachate is3.95%.If electrolytic leachate in the bad condition, the content of Cl2 which gave out can increase to 23.1%. (3)when electrolysis leachate in the Cl- system, the humic acid and phenol can be removed and degraded. The indirect oxidation of ClO- can not only make the high molecular weight organics degrade to low molecular weight organics, but also increase the removal rate of phenol. The ability of direct oxidation organic matters is bad. When electrolytic treatment this kind wastewater , it is necessary to add some Cl- in order to improve the formation of ClO- .The electrolytic production are the middle matters of organic chloride and final matters of organic chloride besides dicarbonate . This may limit the application of electrochemical technology .Must consider the production and control of organic chloride when electrolysis organic wastewater concluding chloride ion.The relationship between the biodegradability of leachate and the the molecular weight distribution of dissolved organic matters is also discussed by lab test. It shows that(1) the degradation of the organic matters that molecular weight are above 100×103u can increase the BOD5/COD of leachate from 0.011 into 0.152. (2)when use biology technology treat leachate, the removal of the organic matters which molecular weight are below 100×103u relate to the organic load and the organic composition. It hasn't direct relationship to its molecular weight.The technological condition of treatment leachate when use alone electrochemical technology and electrochemical-biology complex technology respectively is also studied. The result shows that (1)when use Ru-Ir/Ti anode to treat leachate ,the best technological condition of removal COD is that pH is 9,the electrolytic time is 60min, chloride ion concentration is 8.8g/L and the current density is 9 mA/cm2. The COD of leachate can be deduced from 1360mg/L to 89 mg/L and be satisfied for the one grade discharge standard (GB16889—1997),when electrolytic in this condition.(2) if the current density is smaller or the electrolytic time is longer ,it help to increase the biodegradability of leachate .Electrolytic treatment in the base condition is bad to increase the biodegradability ,the treatment result ofβ-PbO2 anode is idential to MMO anode. When use MMO anode to electrolytic pre-treat the leachate, the suitable technological condition is that pH is 9,the electrolytic time is 40min, chloride ion concentration is 8.8g/L ,the interval of electrode is 2cm and the current density is 3mA/cm2. The BOD5/COD of leachate can increase from 0.093 to 0.32. Use SBR technological to treat the leachate after treated by electrolytic. When treat the leachate in the condition of that temperature is 25℃, the organic matter load is 0.15kgCOD/kgSS,the reaction time is 5 h, the COD of leachate can be deduced effectively .The COD can be deduced from 1360mg/L to 275mg/L and be satisfied for the two grade discharge standard (GB16889—1997) .(3) in the removal of COD, electrochemical-biology complex technology is worse than the alone electrochemical technology, but it has little running cost.
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