Research And Design Of Sludge Dewatering Treatment In A Refinery Wastewater Treatment Plant

At present,our environmental degradation it is on the uptrend,sludge production in our country(in terms of moisture content of 80%)is expected to exceed 60 million tons,including refineries in the "three mud" complex composition,high toxic and hazardous substances,Has been classified as hazardous waste by the state,and the importance of its deep dewatering / drying is obvious.In this paper,based on the research and analysis of a variety of sludge produced by a refinery and sewage plant,the evaluation experiment of sludge mechanical dehydration and the determination of dehydration process were carried out respectively.The key to the process design process is the choice of dehydration equipment,and the use of research results,development and design of the sewage treatment plant sludge dewatering project technology package,the specific results are as follows.The sewage treatment plant according to the source characteristics of the sewage,the proposed high salt series,salt mixed series of sewage treatment facilities,different treatment facilities,including sludge slag,excess sludge and chemical sludge,the sludge has different dewatering properties.Sludge slag oil content of 44210 mg/L,viscosity is not easy to dehydration.The excess sludge contains a large number of biological floc,volatile solids;high water content is not easy to dehydration.Chemical sludge containing gasification hydrogen fluoride produced by the fluoride,aluminum fluoride;high density sedimentation tank in addition to hardness and in addition to silicon produced by calcium carbonate,magnesium hydroxide,magnesium silicate etc.;chemical phosphorus Iron phosphate,calcium phosphate or aluminum phosphate.Chemical sludge particles smaller,low moisture content,more easily dehydrated.According to the difference of sludge dewatering performance,the three kinds of sludge are respectively suitable for dewatering.For the purpose of sludge slag,the process is determined by adding the conditioning agent and then treating the transportation after dewatering,and selecting the dewatering equipment For the horizontal screw centrifuge;For the remaining sludge,the same is the first chemical conditioning selection of horizontal screw centrifuge dehydration treatment;On the chemical sludge,after conditioning,select the plate and frame filter for dehydration.The process package includes several parts of the sludge slag,excess sludge,chemical sludge treatment process,which can be directly used for industrial design.