Experimental On Advanced Treatment Efficiency Of Sewage By Biochemical And Physicochemical Coupling Process

The biological phosphorus removal mechanism is complicated,the phosphorus removal stability is not high,and the phenomenon of phosphorus exceeding the standard occurs from time to time.It is not guaranteed that the effluent phosphorus concentration reaches the national standard,and biological phosphorus removal and biological nitrogen removal exist between sludge age and organic substrates.contradiction.Therefore,on the basis of biological phosphorus removal,it is necessary to combine the biological and chemical methods by adding chemical simultaneous phosphorus removal agents to assist biological phosphorus removal,and to give full play to their respective advantages in wastewater phosphorus removal.In this paper,the activated sludge method is used to treat the domestic sewage water quality indicators,and the effects of system water quality and mud quality under the operation mode of adding FeCl₃and PAC and SBR without adding chemicals are treated.In addition,a comparative analysis of microbial diversity with and without Fe Cl3 and PAC was performed.According to the above studies,the results are as follows:After adding FeCl₃ and PAC,the water quality was promoted,but the effluent quality of FeCl₃was better than that of PAC.With the increase of Fe Cl3,the highest removal rates of COD,TN,TP,and NH4+-N were 92.4%,91.2%,92.5%,and 96.2%,respectively.After adding PAC,the highest removal rates of COD,TN,TP,and NH4+-N were 89%,87.4%,85.3%,and 94.9%,respectively.After Fe Cl3 was added,the removal of organic matter was better than that of PAC.After the two coagulants were added,MLSS increased and SVI decreased in terms of sludge parameters.However,the increase or decrease rate of MLSS and SVI fed with FeCl₃is greater than that of PAC,which indicates that the flocculation of FeCl₃is large,and the weight of inorganic matter in the system is greater than PAC,which gradually accumulates into aggregates,thereby increasing the density of sludge and increasing the density of FeCl₃in the system.Microbial clumps settle faster and are easier to settle.The adsorption neutralization effect is greater than that of PAC.After adding FeCl₃ and PAC,the content of protein and polysaccharide in EPS increased.The polysaccharide content in FeCl₃was 38.8 mg/g MLSS,which was greater than 32.7 mg/g MLSS in PAC,and the protein content was 56.6 mg/g MLSS,which was greater than 50.9mg/g MLSS in PAC.After dosing,the polysaccharide content gradually increased but the growth rate was not as fast as that of protein.On the other hand,the enzyme activity of the system was higher than that of the unadministered microbial activity,but the DHA content of 55.2 mg TF/h·L of FeCl₃was greater than the 47.1 mg TF/h·L of PAC.The composition of the bacterial communities of the three species is quite different.Among them,the OTUs unique to FeCl₃accounted for 19.77%of the total,and the OTUs unique to PAC accounted for 19.07%of the total,all higher than 13.69%of the unadministered pharmaceutical.The Chao index,Shannon and Simpson index showed that the richness and diversity of mesomicroorganisms increased after administration,and the bacterial community with Fe Cl3 was the most abundant and diverse.?-proteobacteria is the most dominant genus,with a relative abundance of 12.5%.