Effects of different concentrations of corn stover on microbial community structure during rumen fluid pretreatment and the biogas production by anaerobic digestion

Abstract

Abstract In this work, the corn stover (CS) with concentration of 3%, 6% and 9% (w/v) were pretreated by rumen fluid and then used for batched mesophilic biogas production. The results showed that after a 6-day pretreatment, VFAs production of 3.78, 8.27, and 10.4 g/L could be found in 3%, 6% and 9%, respectively. When concerning with biogas production, the highest accumulative methane production of 149.1 mL CH4/g VS was achieved by 6% pretreated CS, which was 22% and 45% higher than 3% and 9%, respectively. Also, it was 3.6 times higher than the same concentration of unpretreated CS. The results of microbial community structure revealed highest relative abundance of Firmicutes (45%) and Euryarchaeota (3.9%) in 6% CS, which was beneficial to its high VFAs and methane production. These findings provide scientific reference for the utilization of CS and support the development of agricultural waste resource utilization and environmental protection.