Study On Biofilm Characteristics Of The Domestic Sewage Treatment By Gravel Contact Oxidation Reactor(GCOR)

As the accelerating of urbanization process, the discharge amount of urban domesticsewage increases significantly. The treatment of excess sludge produced in the domesticsewage treatment process were one of the biggest problems that the municipal sewage plantsface at present. The methods of current excess sludge treatment were high energy and capitalcost with low treatment which can not meet the treatment requirement. Therefore, thetreatment and reduction of excess sludge were the core part of present research.In the paper, I study a method of higher efficiency and low energy to conduct domesticwater by comparison with domestic sewage treatment using biofilm reactor under differentenvironmental factors so that we can find a new way of excess sludge reduction technologythat were easy, high efficiency and low capital cost.Using univariate analysis method, robserving and studying the characteristics of whatinfluence biofilm formation ability, that were adherence, extracellular polymeric substanceand cell surface hydrophobicity during hanging membrane phase. Comparision with differentaeration rate, temperature, pH value, and COD load to get COD, NH₃-N degradation ability,then through Minitab software analyse data under the different factors biological membraneproperties, so we the result were that aeration rate, temperature, pH value, and COD load werefour major factors of all, and their order were temperature> aeration rate> COD load> pHvalue, and the rignt environment condation were aeration rate2.0L/min, temperature30℃,pH value7.0, COD load400mg/L.The experiment proves, adherence, extracellular polymeric substance and cell surfacehydrophobicity were three major factors to influence the formation of biofilms ability. Withthe changes in the amount of aeration, temperature, pH, and COD load level factors, adhesionrate, EPS content, CSH value also showed a trend, this trend of the corresponding wastewaterindexes COD and NH₃-N removal rate trend. It can be concluded that the adherence,extracellular polymeric substances and cell surface hydrophobicity three membrane propertiesand wastewater indexes COD and NH₃-N removal rate and biofilm forming ability showed apositive correlation. The adhesion rate that were the greater the higher EPS content, CSHvalue the larger, the stronger the ability of biofilm formation, the stronger the ability todegrade wastewater, the better the sewage treatment effects.