Analysis Of Performance And Microflora Of Anaerobic Granular Sludge Treatment Of Wastewater From Different Antibiotic Production

In recent years,pharmaceutical industry wastewater discharge standards had been continuously improved.However,in the antibiotic production process,the amount of wastewater discharged is large and the content of pollutants is high.Therefore,the treatment is difficult.These problems bring great challenges to enterprise wastewater treatment.In the study,anaerobic granular sludge was used to treat Avermectins,Lincomycin and Tylosin wastewater in an enterprise separately,and the three kinds of wastewater were mixed for comprehensive treatment.Analyze the performance of granular sludge in treatment of different antibiotic wastewater and use high-throughput sequencing technology to analyze changes in microbial community structure.To compare and analysis the 4 group test results,the key technical parameters of the treatment of different antibiotic wastewater by anaerobic granular sludge were obtained,which can provide reference basis for the transformation of anaerobic section in enterprises.Draw the following conclusion:(1)Analysis of operation characteristicsUsed anaerobic granular sludge:while the reactor treating avermectin wastewater is in stable operation,the influent COD concentration was 14000 mg/L and the OLR and the COD removal efficiency were 9.0 kg COD/(m~3·d)and 78%,respectively.Under the stable operating of Lincomycin wastewater treatment,the influent COD concentration was 7000 mg/L and the OLR and the COD removal efficiency were 7.0 kg COD/(m~3·d)and 60%,respectively.Treatment of Tylosin wastewater reactor in normal operation,the maximum OLR could reach4.5 kg COD/(m~3·d)and the influent COD concentration and the COD removal efficiency were 5000 mg/L and 75%,respectively.The maximum OLR of mixed wastewater treatment was 4.0 kg COD/(m~3·d)and the influent COD concentration and the removal rate were 5000 mg/L and about 70%,respectively.The results showed that,compared with the mixed treatment,the wastewater from different sources can be collected separately for anaerobic treatment,which can achieve higher treatment efficiency.(2)Performance analysis of anaerobic granular sludgeThe mature anaerobic granular sludge was used to treat different antibiotic wastewater.The particle size distribution of the granular sludge in each reactor increased first and then decreased.The VSS/TSS value of the sludge increased first and then decreased.Compared with the 0.60 value of the inoculated sludge VSS/TSS,the VSS/TSS in the reactor reached above 0.68 at the highest.When the reactor could operate steadily with a maximum OLR,the sedimentation performance and surface condition of the sludge were relatively poor,indicating that the complex and changeable water quality of antibiotic wastewater would adversely affect the performance of granular sludge.At the same time,the worse biodegradability of wastewater can result the greater negative effects on sludge.(3)Microbial community analysisAt the end of the experiment,the microbial flora in the sludge of different reactors still had a high diversity and a certain similarity.At the phylum level,compared with the inoculation sludge,the relative abundance of Euryarchaeota in the other three groups decreased during the operation process except 2#reactor.However,the relative abundance of Euryarchaeota still occupied a large proportion in the four groups of experiments.Meanwhile,the relative abundance of Bacteroidetes,Proteobacteria and Firmicutes had increased and became the main functional phylum.In addition,the relative abundance of Others decreased,indicating that the relative abundance of dominant phylum increased during the experiment.At the genus level,the relative abundance of dominant genus in the four reactors was significantly different.Compared with the inoculation sludge,except 2#reactor,the relative abundance of Methanothrix,Methanobacterium and Methanomethylovorans in the other three groups of reactors decreased,but still accounted for a large proportion.When the four groups of reactors were operating in good operating state,the relative abundance of dominant genus all increased and the unique bacteria Prevotella appeared in 4#reactor.