Treatment Efficiency And Influencing Factors Of IBP-containing Wastewater By SBR Process

As a commonly used analgesic and anti-inflammatory drug,ibuprofen has been widely used around the world,but the large-scale use of ibuprofen has also caused certain harm to aquatic plants,animals,and even human bodies.The biological treatment technology of ibuprofen wastewater has attracted extensive attention from scholars at home and abroad due to its simple process design,low cost,no hazardous by-products,high removal efficiency,and obvious sustainable development.This topic uses SBR process to treat ibuprofen-containing wastewater,explores the degradation effect of SBR process on ibuprofen,and further analyzes the p H value of influent water,ibuprofen concentration(IBP),carbon-nitrogen ratio(C/N),carbon-phosphorus ratio The effects of(C/P)and hydraulic load(HRT)on the degradation of IBP in the SBR process,and revealed the structure and composition of microbial flora from a microscopic perspective to enhance the ability of microorganisms to treat ibuprofen-containing wastewater.The main findings are:The removal rate of COD during the cultivation and acclimation periods was greater than 85%,the removal rate of ammonia nitrogen was greater than 95%,the removal efficiency of total phosphorus decreased from 95% in the cultivation period to 85% in the acclimation period,and the average degradation rate combined with IBP was greater than 80%,indicating that Biodegradation of IBP was feasible;the results of scanning electron microscopy showed that the spatial structure of sludge in the acclimation period was more obvious than that in the culture period.High-throughput sequencing technology showed that the input of IBP had little effect on the number of microbial populations,but the community diversity was significantly reduced.The content of extracellular polymer increased sharply from 67.11 mg/g MLSS in culture period to 156.32mg/g MLSS in acclimation period,which was mainly caused by the increase of protein content from 42.44 mg/g MLSS to 89.80mg/g MLSS.The results of three-dimensional fluorescence spectroscopy showed that the composition of extracellular polymer compounds did not change significantly during the culture acclimation stage,all of which were soluble microbial metabolites and humic acids.Acidic conditions can inhibit the removal rate of activated sludge pollutants,while neutral conditions have little effect on the removal of activated sludge pollutants,so the p H value is usually controlled under neutral conditions in practical projects;the scanning electron microscope results show that the p H value is 5.5 The sludge structure was loose and irregular floc structure,and there was sludge disintegration phenomenon.The activated sludge structure was more compact when the p H value was 7 and 8.5.The COD degradation rate is inversely proportional to the influent IBP concentration,and the higher the IBP,the more obvious the inhibitory effect.The degradation rate of ammonia nitrogen decreased from 0.56 mg/min when the IBP was 1 mg/L to 0.29 mg when the IBP was 3 mg/L and 5 mg/L./min;SEM results showed that when the concentration of IBP was 1 mg/L,the spatial structure of the sludge was obvious and compact,and when the concentration of IBP was 5 mg/L,the sludge structure was looser and showed an irregular floc structure.With the decrease of influent C/N,the removal rate of COD,ammonia nitrogen and TP decreased gradually;SEM results showed that the spatial structure of sludge was obvious and compact under three different C/N.The removal rate of ammonia nitrogen at C/P=100:1 was 96.78% higher than 91.29% at C/P=100:1.5 and 92.78% at C/P=100:2;SEM results showed that the three different C Under /P,the spatial structure of sludge was not obvious.The removal rate of total phosphorus at HRT=12was 84.96%,which was significantly higher than that of TP at HRT=9 and HRT=15,which was 62.90% and 63.60%,indicating that HRT=12 was more conducive to the removal of TP.When HRT=9,the sludge structure is loose and irregular floc structure.When HRT=12 and HRT=15,the spatial structure of activated sludge is obvious and compact.The population abundance and bacterial diversity of microorganisms under alkaline conditions were lower than those under neutral and acidic conditions;the absolute dominant phylum-level flora under different p H values was Proteobacteria.With the increase of IBP,the abundance of microbial population first decreased and then increased;the absolute dominant phylum-level flora under different IBP concentrations were all Proteobacteria.With the decrease of influent C/N,the richness and diversity of microbial community increased rapidly,but when C/N=100:10,the diversity of microbial population was lower than that of C/N=100:8;different C/N The lower absolute dominant phylum-level flora were all Proteobacteria.The microbial analysis trend corresponding to C/P and C/N is the same,and the absolute dominant phylum-level flora under different C/P is Proteobacteria;the colony abundance and diversity of HRT=12d are higher than those of HRT=9h and HRT=15h,when HRT=12,more suitable microbial growth and reproduction;the absolute dominant phylum-level flora under different HRTs are Proteobacteria.