Effect of different concentrations of anaerobic sludge on corn stalk biogas production

[Objective]This research studied the gas producing characteristics of corn stover under different inoculum concentration in order to provide reference for straw application in large scale biogas engineering. [Method]Using the corn stalks as raw material for fermentation, different proportions of anaerobic sludge were vaccinated. Then, using the batch fermentation process, anaerobic fermentation was conducted under 38℃. [Result]After 50 d of fermentation, most of materials in straw decomposed. When the ratio of anaerobic sludge and straw was 10∶3 (the TS rate was 0.57 and VS rate was 0.46 for both) and the total TS concentration was at 10.16%, the straw gasification effect was optimal, in which the gas production rate was 370 mL/g TS and the methane content of biogas was 56.04%. [Conclusion]As the inoculation sludge percentage increased, the straw gas production quantity and gas production rate gradually increased, but when the inoculum size reached a certain ratio, increases on the raw biogas production and biogas production rate were no longer significant.