Sludge Dewatering Agentia Research In Small And Medium-sized Cities Sewage Medicament Treatment Plant

Municipal wastewater and industrial sewage in the sewage treatment plant willoften produce large amounts of sludge.Sludge has the characteristics,such as highmoisture content， large volume，habitude instability，easy to corrupt and odor,notconducive to the transport and disposal.The use of activated sludge sewagetreatment in medium and small sewage treatment plant will produce large amountsof excess sludge in our country.medium and small sewage treatment plantsgenerally ofen use more mechanical thickening and dewatering.Due to the uniquecharacteristics of the sludge,sludge dewatering performance is bad,directlydehydrated difficult to achieve.Sludge disposal costs in China accounted for20%to50%of the total operating costs of the sewage treatment plant,or even as high as70%.The sludge treatment of municipal sewage treatment plant sewage treatmenthas become a "bottleneck" problem.Therefore,in order to facilitate subsequentprocessing in sludge dewatering of sludge conditioning, and chemical conditioningis the most talked about conditioning.By changing the physicochemical properties of the surface of the sludgeparticles and the component,the chemical conditioning agents,destruction of thecolloidal structure of the sludge,and to reduce the affinity with water,so as toimprove the dewatering properties.Because the operation is simple,maturetechnology,and the effect is significant,so Chemical conditioning become acommonly used method.Therefore,how to search a new low price,a significanteffect of conditioning agents become important research work one.In consideration of current situtation and laboratory feasibility in sewagetreatment plant,the experimental sludge sludge mud sump as the object of study.Thepaper studied the impact of a variety of chemicals,pharmaceutical dosagepharmaceutical composite sludge dewatering performance.Experimental resultindicates that monadelphous calcium oxide and diatomite result is well,cansignificantly reduce the specific resistance of the sludge, enormously improvesludge dewatering.Along with conditioner adding，the specific resistance of sludgewas gradually reduce,illustrates the conditioners began to play a role, but when the agents continue to increase by more than a certain value,the specific resistance ofsludge up instead,It is verified whether single or multiple drug combination has itsoptimal dosing quantity.On the basis of a large number of test data,based on the cost of sludgetreatment,and the effect on environment into account,monomer chitosan andcalcium oxide,ferric sulfate compound with the sludge conditioner forchoice.Calcium additive quantity of4g/100ml,6g/L of ferric sulfate and50mg/L of chitosan for its optimal dosing quantity.In this experiment can make thespecific resistance of sludge is reduced from109to108~107orders of magnitude,the filter cake moisture content to70%~80%.And chitosan, non-toxic harmless tothe environment pollution-free,calcium oxide, ammonium ferric sulfatedodecahydrate cheap, abundant source.Finally, through theoretical analysis, simple dewatering mechanism of variousagents are discussed,and the defects and the insufficiency of experiment.