High Efficiency Anaerobic Process Of Antibiotic Fermentation Residue

Antibiotic fermentative residues has rich organic matter,which may induce drug-resistant bacteria and biological toxicity,etc.Anaerobic treatment technology is an efficient biomass conversion technology,which can not only eliminate most of the viruses and bacteria,but also convert the organic matter into biogas for recycling.At the same time,it can partially degrade compounds or toxic substances with complex structure.Therefore,anaerobic treatment technology is an effective way to treat antibiotic fermentation residue which can make it harmless and resourceful.However,there are few reports on anaerobic treatment of antibiotic fermentation residus,and the removal load of anaerobic reactor is low.Therefor,this paper adopted the modified internal circulation(MIC)anaerobic reactor to treat antibiotic fermentation residus.The improvement of the reactor is that the modified IC anaerobic reactor with the external circulation pipe between the first reaction zone and mixed zone improved hydrodynamics and mass transfer between substrate and sludge,resulting in the increase of the reactor treatment efficiency.Fistly,the activated sludge was used as the inoculated sludge,and then the lycopene waste liquid with good biodegradability was used as the substrate to start the MIC reactor.At last,anaerobic treatment process of vancomycin and declomycin fermentative residues was studied.The main results are as follows:After the MIC reactor was successfully started,it had a good treatment effect on lycopene waste liquid.When the COD(Chemical Oxygen Demand),TN(Total Nitrogen)and TP(Total Phosphorus)concentration of the incoming water were 30000to 32000 mg/L,853 mg/L and 280 mg/L at the HRT(Hydraulic Retention Time)of 4days,respectively,the COD,TN and TP removal efficiency were 90%,45%and 35%,respectively.At this time,the demand of anaerobic microorganisms for nutrients was COD:N:P=250:5:0.8.The removal efficiency of vancomycin could reach more than 90%when the anaerobic treatment of vancomycin fermentation residus was stable.At this time,the demand of anaerobic microorganisms for nutrients was COD:N:P=250:5:0.8.When the COD,TN and TP concentration of influent were 30000 to 40000 mg/L,1400 to 1500 mg/L and 150 to 160 mg/L at the HRT of 3 to 4 days,respectively,the COD,TN and TP removal efficiency was 87%to 90%,40%to 50%and 40%to 50%,respectively.At this time,the effluent Volatile Fatty Acid(VFA)was less than 1000mg/L.When the HRT was 2 days,the inlet water load was 25 kg COD/(m~3·d),the removal load reached a maximum of 19.5 kg COD/(m~3·d),and gas production reached a maximum of 188 L/d.Through the analysis of dynamic characteristics,the Modified Stover-Kincannon dynamic model was more suitable for the study of this experiment than the Monod dynamic model.The removal efficiency of declomycin could reach more than 80%when the anaerobic treatment of declomycin fermentation residus was stable.At the time,the demand of nutrients was COD:N:P=350:7:1.When the COD,TN and TP concentration of the influent was 21000 mg/L,800 to 1000 mg/L and 75 to 85 mg/L at the HRT of 4 days,the COD,TN and TP removal efficiency was over 90%,48%to 52%and 78%to 82%,respectively.At this time,the effluent VFA was less than 300 mg/L.When the HRT was 3 days,the COD concentration of influent was 30532 mg/L,the COD removal efficiency was 83.2%,VFA was 456 mg/L,and the gas production reached a maximum of 126.8 L/d.Through the simulation analysis of Modified Stover-Kincannon kinetic model,the kinetic equation was y=1.004x+0.044,R~2 was0.989.During the anaerobic treatment of lycopene waste liquid,vancomycin and declomycin fermentation residus,the microbial community structure would change with the change of the matrix.Actinobacteria was the dominant bacteria and Methanosaeta was the dominant methanogen in the anaerobic treatment of lycopene waste liquid.Bacteroidetes was the dominant bacteria and Methanobrevibacter was the dominant methanogen in the anaerobic treatment of vancomycin fermentation residus.Firmicutes and Synergistetes were the dominant bacteria and Methanosphaera was the dominant methanogen in the anaerobic treatment of declomycin fermentation residus.By detecting the changes in antibiotic resistance gene and integron gene in the anaerobic treatment of declomycin fermentation residus,it was found that anaerobic digestion could effectively remove antibiotic resistance genes and integron genes from the declomycin fermentation residus,which could weaken the transmission of antibiotic resistance genes.