Microbial Community Characteristics of High Solid Content Anaerobic Digester of Municipal Solid Waste

Abstract

The composition of municipal solid waste(MSW) including water content, cellulose content, organic ingredients, etc were examined.Through to the municipal organic waste anaerobic digestion experiment, analysis the characteristics of anaerobic acidification bacteria, ammonifying bacteria, cellulose degradation bacteria and methane bacteria along with time and spatial distribution,and analysis the function between microbial community and the relationship of the metabolites.The results show that in the early period of municipal waste anaerobic fermentation, large amounts of oxygen exist in the reactor, aerobic and facultative anaerobic bacteria proliferate,it is the main groups of raw material transform into organic matter.Along with the formation of the anaerobic environment and rich nutrients, the number of anaerobic bacteria began to rise.The anaerobic acidification bacteria prior to reach maximum than ammonification bacteria and occupy the dominant position.The methane bacteria doesn’t proliferate at the startup phase, and the peak value is 3.24×10⁹/ml at the 25th day,then to be stable,the anaerobic cellulose-decomposing bacteria grow slowly.In the space,the number of anaerobic acidification bacteria,anaerobic ammoniation bacteria and methane bacteria both are more in middle and bottom position;the anaerobic cellulose-decomposing bacteria proliferate in the bottom.In addition,the change trend of volatile fatty acids and concentration of ammonia nitrogen is consistent with the bacteria number in space.The VFA composition of biogas slurry is given priority to with butyric acid,fermentation type belong to butyric acid fermentation.