Effect of biopretreatment on biogas production characteristics of anaerobic fermentation of corn stalk

Slow decomposition and low rate of biogas production are constraints that using straw as anaerobic fermentation materials, biopretreatment can accelerate straw decomposition and increase biogas production rate. Biogas slurry was used to pretreatment corn stalk, compared with Microbe Decomposition Agents, Easy Composting Agent, complex microbial agent, sugar fermentation enzyme, and water treatment was used as control, anaerobic digestibility and biogas yield of corn stalk were evaluated by anaerobic batch digestion experiments. The results showed that, pretreatment of biogas slurry was better, the cumulative biogas production of 227.67 mL· g-1VS was obtained after 43 days of digestion, increased by 5.01%-81.2% as compared to other pretreatment methods. The cumulative biogas production of sugar fermentation enzyme was 125.64 mL · g- 1VS, which was the lowest among all pretreatment's. In addition, the total alkalinity of biogas slurry treatment was the highest, and had strong buffer capacity, VFA decomposition was fast, which led the highest biogas production. Biogas slurry pretreatment had a significant effect on increasing biogas production rate of straw.