Study On Modification Of Municipal Sludge Biological Carbon And Its Adsorption Of Phosphate In Water

With the continuous development of industry and agriculture and the increasing production activities in China,environmental pollution and resource shortages are becoming more and more serious.Sludge is a by-product of sewage treatment.Due to its complex composition and serious pollution,it needs to be treated and disposed of reasonably.In recent years,due to the use of phosphorus-containing products,a large amount of phosphorus has been discharged into water bodies along with municipal sewage,industrial wastewater and surface runoff,causing phosphorus pollution in water bodies.Therefore,the important method to solve the water eutrophication is to removal the excessive phosphorus in water bodies.Through pyrolysis of municipal sludge at different temperatures,the solid product biomass carbon was obtained and modified.By exploring the adsorption and desorption of phosphorus by biological carbon under different conditions,the feasibility of removing phosphorus from water by biological carbon and the reusability of biological carbon were analyzed.A new way was found for the reuse of municipal sludge.The main research contents of this paper are as follows:(1)First,the undigested dewatered sludge of the municipal sewage treatment plant should be dried,and then the treated dry mud is subjected to pyrolysis at different temperatures to prepare conventional biological carbon(BCX,where X represents pyrolysis temperature),By analyzing the adsorption of phosphorus by different biological carbon,the optimal pyrolysis preparation temperature of biological carbon was determined.it was found that when the final pyrolysis temperature was 700 C,the adsorption effect of biological carbon on phosphorus was the best.Therefore,BC700 was magnetized to prepare magnetic biological carbon MBC700.(2)The BET,SEM and FTIR measurements of BC700 and MBC700 were carried out.The characterization,specific surface area,pore structure and functional group structure of the two biomass carbons were compared to analyze the mechanism of adsorption of pollutants by biomass carbon.(3)Comparative analysis of phosphorus adsorption in water by BC700 and MBC700 under different conditions,including the effect of dosage,pH value,adsorption kinetics experiment,adsorption isotherm experiment,the effect of coexisting ions,after conducting a series of laboratory studies,the adsorption of phosphorus in real water by two biologicl carbon was also analyzed.By analyzing the adsorption of phosphorus in water by biological carbon under different conditions,the mechanism of phosphorus adsorption by biologicl carbon was analyzed and the optimum adsorption conditions were determined.(4)Comparative analysis of BC700 and MBC700 desorption of phosphorus,including the effect of desorbent concentration,dosage,desorption time,and experimental determination of the recyclability of two biochars,and the desorption and reusability of the two biological carbon were analyzed.Through the experimental results of this subject,it can be seen that the modified biological carbon has better reusability of phosphorus adsorption,and the modified biological carbon has magnetism,it can be better recovered from water.The adsorption of phosphorus in water by biological carbon prepared by sludge pyrolysis not only realizes the resource utilization of municipal sludge,but also alleviates phosphorus pollution in water.