| Burying garbage wholesomely is one of the main processing methods tocity garbage of our country, it comes into being landfill leachate, which is akind of high-concentration organic waste water, great variation in compositionand flow rate, and its compounds are complex and change with"field age". Atpresent, dealing with landfill leachate adopt various combination mostlydomestic and oversea. The main distinctness of combination is preprocessingphase. In preprocessing phase, whether or not to improve the ability ofbio-chemical and to decrease total nitrogen and COD are important basis forchoosing treatment process. In this paper, hydroxyl radical oxidation wasused as preprocessing phase which associated with Co/zolite adsorption, andvarious index removal efficiency are 80.1% for COD, 96.7% for the NH3-N,respectively.Because hydroxyl radical(?OH) has high oxidation potential(2.8eV), itcan react with most of organic pollutant or poisonous or harmful materialwithout selectivity. The reaction turns harmful material into CO2 H2O or themineral salt, without secondary pollutions. In recent years, electrolysisoxidation technique was used to treat landfill leachate, because its availabilityand the low expenses and the operation convenience, and it comes in forparticular favor. With electrolysis technical development, especially theapplication of new electro-catalytic electrode material, the electrolysistechnique will develop at fast speed. This paper made use of thermalformating SnO2+Sb2O3 middle layer, electro-depositing PbO2 outer, combining a little La to make Ti base PbO2 electrode, which can producehydroxyl radical during the electrolysis process to treat landfill leachate .In the process of landfill leachate treated by hydroxyl radical, electrodematerial, pH value, current density, support electrolytes are all factors whichinfluence result. From SEM we can see, in the process of electro-deposit outer,comparing with the electrode without La, PbO2 deposition coating crystal iseven and fine. At the same time, crystal is regular which has large specificsurface area; the pH value influence electric potential of oxygen evolution andhydrogen evolution reaction, NH3-N removal efficiency was highest inalkalescent environment (pH=10.00), NH3-N removal efficiency is 100% afterbeing electrolyzed for 3 hours, because under the alkaline condition ,electrolysis generated a great deal of ?OH which cause high removalefficiency; the current density is an important influence factor of electrodeelectrolysis oxidation reaction. Removal efficiency of NH3-N increased withcurrent density increasing, when current density is increased from 4.3A/dm2 to8.4 A/dm2 in 4 hours, NH3-N removal efficiency also rises from 57.9% to100%; during the process of electrochemical oxidation, different supportelectrolyte was used to inquire into its influence. NH3-N removal efficiency ishigher by using sodium chloride as electrolyte than that by using sodiumsulfate or without electrolyte. Under the same ex periment condition, NH3-Nremoval efficiency are 100%, 92.1%, 93.4%, respectively. For the sake ofinvestigating the influence of the concentration of Cl- during the process ofelectrochemistry oxidation landfill leachate further, change the concentrationof Cl-, when the concentration of Cl- in leachate from 0.05mol/L to0.1mol/L, NH3-N removal efficiency also increase from 57.9% to 100%. The experiment condition were optimized finally, NH3-N removal efficiency is100% after being electrolyzed for 3 hours with Ti/PbO2 electrode thatcontained a little La when current density was controlled under 8.4 A/dm 2, pHwas 10 and the concentration of sodium chloride electrolyte was 0.1mol/L.When Co/zolite sorbent treated landfill leachate, the factor that influentCo/zolite sorbent function not only associate with its structure, reactivetemperature, raw material ratio etc, but also relate to its dosage, pH value,adsorption time and water velocity etc. This paper used soakage method toproduce sorbent which zolite as carrier, Co as active component. Study onCo/zolite adsorb characteristic of dynamic state and static state. Experimentindicate that Co/zolite adsorb NH3-N well, adsorb capacity at dynamic state isbigger than that at static state; adsorb efficiency increased with the incrementof adsorbent dosage increasing, adsorb efficiency near to 80% when adsorbentdosage attain 14g/L, apparently, increasing adsorbent dosage further can makeadsorb efficiency higher, but increasing processing cost. In this experiment,we adopt a lower adsorbent dosage 7g/L; with pH value increase, NH3-Nremoval efficiency on Co/zolite is also increase d, although removal efficiencyis slightly higher under alkalescency condition than other one, change rangeisn't too big, basic tend is steady, it indicates that Co/zolite has good adsorbentcapability in width scope, but removal efficiency increase significantl y understrong alkaline condition, it illuminates that strong alkaline condition isadvantageous for Co/zolite adsorbing NH3-N in landfill leachate; theconcentration of water is higher, penetrate time is shorter. So in order toprolong the life of adsorbent and protract penetration time, we can pretreatlandfill leachate properly, lower the concentration of landfill leachate; water velocity is smaller, commutative capacity is bigger, the result is better, but inpractical operation we hope to have great exchange capacity and biggercurrent velocity, in order to harmonize conflict , we will adopt proper currentvelocity.Treating landfill leachate by hydroxyl radical oxidating and Co/zoliteadsorbing in this paper, the landfill leacate comes from a certain garbage fieldin Changchun. The concentration of NH3-N is 1260mg/L, the TOC is5752mg/L, after being electrolyzed for 2 hours at Ti/PbO2 electrode thatcontained a little La when current density was controlled under 8.4A/dm 2, pHwas 10 and the concentration of sodium chloride electrolyte was 0.1 mol/L,using Co/zolite sorbent to carry on a depth disposal for landfill leachate gained,when current velocity is 16.3ml/min, the adsorbent dosage is 7g/L, adsorped fora period of time, NH3-N removal efficiency reached 96.7%, TOC removalefficiency attain 80.1%.
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