Performance of indigenous bacteria during the biogenic gas generation from brown coal

Abstract：In order to verify the functional mechanism of microbial community in biogenic gas generation progress from brown coal,we used anaerobic glove chamber as the experimental platform to enrich and cultivate active methanogen flora from freshly collected brown coal samples from Zhaotong basin,Yunnan Province,China.A simulating experiment of biogenic gas from brown coal was conducted with these indigenous bacteria.The amounts of fermentation and syntrophic acetogenic bacteria,and the activities of cellulase and coenzyme F420 were analyzed during the experiment.The results show that the fermentation bacteria kept quite active（≥7.5×106/mL） throughout the biogas generation process;and both the amount and breeding rate of syntrophic acetogenic bacteria were smaller than that of fermentation bacteria.But the amounts of both kinds of bacteria had the same changing trend,which shows significant inherited food chain-related relationship.The activities of cellulase remained fairly（0.018-0.023 mg/（mL·h））;while those of coenzyme F420 could have been inhibited by the acid substances created by acidogenic fermenting bacteria.The minimum activity values were 55.91%-67.61% of the peak values.The activities of coenzyme F420 had two peak times in the biogenic gas generation progress from brown coal,indicating periodic characteristics of biogenic coalbed methane generation from brown coal.