Study On Deep Dewatering Mechanism Of Municipal Sludge By Oxidation Disintegration-membrane

As development of urbanization, capacity of wastewater treatment in Wastewater Treatment Plant was enhancing,with producing lots of sludge. Safetily treatimg and disposaling of sludge have become major problem which troubles wastewater treatment in environmental fields. The reduction,harmless, stabilization and reusing of sludge from Wastewater Treatment Plant was restricted by the high moisture content of sludge.The treatment and disposal of sludge have become a serious problem, which lead the sludge deep dewatering reduction to a necessary.This paper completed the stduy on deep dewatering mechanism of sludge using the technology of Oxidation Disintegration-membrane.It was based on analysising the existing problems of difficult dewatering and the present treatment and disposal of sludge. The technology of Oxidation Disintegration-membrane with treating sludge was optimized. The aim with reduction,harmless and stabilization of sludge,which was the most advantageous for sludge reusing and safetily landfilling,was realized. Major works as follow:(1). The dewatering effects that sludge was conditioned by single chemical conditioning agent and complex gather-sinking agent got by orthogonal compound experiment to dewater were investigated. Experiments show:the moisture content of 65% in sludge cake was achieved by using the optimum complex gather-sinking agent.(2). The influences of the ozone dosage on the dewatering performance of sludge including SV30, r and the moisture content of cake,was investigated. Experiment results:Under little ozone dosage (0.002-0.006gO3/gSS), The dewatering performance of sludge including SV3o,r and the moisture content of cake descend as increasing of ozone dosage. At ozone dosage 0.005 gO3/gSS, the minimum of specific resistance (r)wasl.15×1012m/Kg; the minimum of the moisture content of cake was 57.9%.(3). The influences of the ozone dosage on the properties of sludge including MLSS, MLVSS,the solubility COD, the content of solution protein, the pH value of sludge solution, was investigated. Experiment results:At ozone dosage0.002-0.006gO3/gSS, the reduce rate of solubility pH, MLSS,MLVSS were slow, but the increment rata of solubility COD and the content of protein were quick. At 0.005gO3/gSS of ozone dosage, SEM showed that original sludge membrane was disintegrated by Oxidation Disintegration-membrane. The kinetics relationship modes among the dewatering rata, ozone concentration were explored based on the method of dualistic linear regression. The conclusion showed that the deep dewatering reaction of directing ozonation was zeroth order radical reaction.Mechanisms analysis:under little ozone dosage (0.002-0.006gO3/gSS), sludge germ colloform was purposefully disintegrated by induction Oxidation Disintegration-membrane;the lots of water remove out of the sludge flocculent,but the inner organic matters were not non-selectivly disintegrated with produce of organic acids and CO2.(4). The technology optimized parameters of Oxidation Disintegration-membrane were used for projiect case. Further proof shows:surface organic layer of sludge germ colloform was quickiy disintegrated by the technology of Oxidation Disintegration-membrane,to achieve the effect of deep dewatering.Therefore, the technology is a advanced and promising technology for sludge deep dewatering,playing important part to deep treating and safetily disposaling sludge.