Anaerobic Treatment Of Corn Alcohol Waste Water And Prokaryotic Microbial Community Analysis

Alcohol wastewater is a kind of polluted organic wastewater produced in the bio-production of alcohol.Anaerobic digestion is one of the most important methods for treating alcohol wastewater.Through anaerobic digestion,biogas was obtained for using as distillation substitution coal,which not only saved energy consumption,but also benefited for protecting environment.The research and application of high-efficiency anaerobic reactor played an important role in the treatment of alcohol wastewater.In order to get optimized process parameters for the treatment of corn alcohol wastewater by three high-efficiency anaerobic reactors,including UASB,EGSB and IC.And learn about the microbial community in each reactor.The start-up and operation of these three high-efficiency anaerobic reactors were studied,and the microbes in the three reactor granular sludges were analyzed based on 16S amplicon sequencing.The experimental results showed that:During the UASB process of treating corn alcohol wastewater,the influent COD concentration gradually stabilized about 20,000 mg/L.HRT was shortened to 1.9d,COD removal rate was above 95%,average methane content in biogas was 60.29%,The organic loading rate exceeded 10.56kg/(m~3·d),and volume gas production rate was up to 7.88m~3/(m~3·d).In the experimental process of EGSB anaerobic reactor for treating corn alcohol wastewater,when the influent COD concentration reached about20000 mg/L,the optimum reflux ratio was 4:1 under the normal temperature condition of HRT at 4.1d.HRT was gradually shortened to 1.4d.The average COD removal rate during the experiment was 95.8%,the average methane content in biogas was 60.39%,the organic loading rate was up to 14.8kg/(m~3·d),and the highest volume gas production rate was 10.72m~3/(m~3·d).During the experimental process of treating corn alcohol wastewater by IC anaerobic reactor,the influent COD concentration was gradually increased approximately to 20000 mg/L,the HRT was shortened to 1.6d.The COD removal rate reached more than 95%during the experiment,the average methane content in biogas was 61.42%,the organic loading rate reached 12.58kg/(m~3·d),and the highest volume gas production rate reached 10.22m~3/(m~3·d).Bacteria and archaea were detected in the three reactors'granular sludge samples.The dominant microbes were Firmicutes,Bacteroidetes,Proteobacteria,Synergistetes and Euryarchaeota.Bacterial diversity was higher than archaea.The number of bacteria detected in the three reactors ranged from 148 to 230,while the archaea ranged from 5 to 10.In the process of anaerobic digestion of corn alcohol wastewater,the retention or change of dominant microbes were closely related to reactor type,running time,wastewater characteristics and process parameters.