Long-Term Mesophilic Anaerobic Co-Digestion of Swine Manure with Corn Stover and Microbial Community Analysis
Haipeng Wang, Teng Teeh Lim, Cuong Manh Duong, Wei Zhang, Congfeng Xu, Lei Yan, Zili Mei, Weidong Wang
Abstract
Long-term anaerobic co-digestion of swine manure (SM) and corn stover (CS) was conducted using semi-continuously loaded digesters under mesophilic conditions. A preliminary test was first conducted to test the effects of loading rates, and results indicated the 3 g-VS L−1 d−1 was the optimal loading rate. Based on the preliminary results, a verification replicated test was conducted with 3 g-VS L−1 d−1 loading rate and different SM/CS ratios (1:1, 2:1 and 1:2). Results showed that a SM/CS ratio of 2/1 was optimal, based on maximum observed methane-VSdes generation and carbon conversion efficiency (72.56 ± 3.40 mL g−1 and 40.59%, respectively). Amplicon sequencing analysis suggested that microbial diversity was increased with CS loading. Amino-acid-degrading bacteria were abundant in the treatment groups. Archaea Methanoculleus could enhance biogas and methane productions.