Study On Enhanced Electrochemical Oxidation Treatment Of Landfill Leachate Membrane De-Concentration Solution

In this study,the characteristics of high content of salt in the leachate membrane de-concentration solution were treated by electrochemical oxidation,and the chemical oxygen demand removal rate was used as the investigation index,using pulse strengthening and Fenton strengthening.The DSA electrode strengthening technology strengthens the electrochemical oxidation process.In the experiment,the single factor method was used to screen each reaction condition,and the method of better strengthening effect was optimized by response surface method,and the interaction effect was analyzed.Three-dimensional fluorescence spectroscopy and gas chromatography-mass spectrometry were used to analyze the changes of organic components.The conclusions are as follows:?1?In the basic experiment of electrochemical oxidation,the COD_cr removal rate was41%under the conditions of peak voltage=10V,pH=5,and pulse frequency=5000 Hz after pulse enhancement.After Fenton fortification,pH=3,current density=30mA/cm²,and H₂O₂dosage=7.5mL,the removal rate of COD_cr was 65.2%.It shows that the pulse strengthening has little improvement on the oxidizing ability,so Fenton strengthening is used.?2?Response surface experiment results show that the relationship between various factors on COD_cr removal rate is:H₂O₂ dosage>pH>current density,the modelgives regression equation:COD_cr removalrate=64.64-1.69×A+4.69×B+1.27×C-2.30×A×B+0.88A×C+0.57×B×C-8.75×A²-5.25×B²-0.67×C²,the best experimental parameters are given:pH=2.95,H₂O₂ dosage=8.16mL,current density=32.99mA/cm²,the model fitting equation gives a corresponding removal rate of 66.50%.The tested model can better predict the COD_cr removal rate,indicating that the model is more accurate.On the basis of this,the COD_cr removal rates were 67.4%and69.8%,respectively,after the strengthening of PbO₂/Ti and RuO₂-IrO₂/Ti DSA electrodes,indicating that the RuO₂-IrO₂/Ti strengthening effect is better.?3?The humic acid and fulvic acid with higher fluorescence response intensity in the landfill leachate membrane de-concentration solution have higher degradation efficiency at the initial stage of the reaction,and the humus is most oxidized.GC-MS analysis showed that Fenton enhanced electrochemical oxidation has good oxidation effect on benzene series and triple bond compounds in the leachate membrane decondensation solution.The formation of chlorinated hydrocarbons indicates that chloride ions in raw water do play a role.Indirect oxidation.Figure 41,table 10,reference 63.