Ensiling excessively wilted maize stover with biogas slurry: Effects on storage performance and subsequent biogas potential

Hui Sun; Xian Cui; Walter Stinner; Leping Zhang; Xinxin Ju; Jianbin Guo; Renjie Dong

doi:10.1016/j.biortech.2020.123042

Ensiling excessively wilted maize stover with biogas slurry: Effects on storage performance and subsequent biogas potential

Bioresour Technol. 2020 Jun:305:123042. doi: 10.1016/j.biortech.2020.123042. Epub 2020 Feb 19.

Authors

Hui Sun¹, Xian Cui¹, Walter Stinner², Leping Zhang¹, Xinxin Ju³, Jianbin Guo⁴, Renjie Dong⁵

Affiliations

¹ College of Engineering (Key Laboratory for Clean Renewable Energy Utilization Technology, Ministry of Agriculture), China Agricultural University, Beijing 100083, PR China.
² German Biomass Research Center, Deutsches Biomasseforschungszentrum gemeinnützige GmbH, Torgauer Str. 116, 04347 Leipzig, Germany; Sino-German Biomass Research Center Anhui, Hefei University, Jinxiu Dadao 99, 230601 Hefei, PR China.
³ Yantai Institute, China Agricultural University, Yantai 264032, Shandong, PR China.
⁴ College of Engineering (Key Laboratory for Clean Renewable Energy Utilization Technology, Ministry of Agriculture), China Agricultural University, Beijing 100083, PR China. Electronic address: jianbinguo@cau.edu.cn.
⁵ College of Engineering (Key Laboratory for Clean Renewable Energy Utilization Technology, Ministry of Agriculture), China Agricultural University, Beijing 100083, PR China; Yantai Institute, China Agricultural University, Yantai 264032, Shandong, PR China.

PMID: 32105847
DOI: 10.1016/j.biortech.2020.123042

Abstract

This study evaluated the ensiling performance of excessively wilted maize stover (EWMS) with biogas slurries and the effect on the subsequent biomethane potential. Chicken and pig manure biogas slurries with or without solid-liquid separation were used to amend the stover humidity before ensiling for 60 d. The hetero-lactic-acid fermentative bacteria Atopostipes and Lactobacillus were enriched by the biogas slurry regardless of the solid-liquid separation. Significant increases in the total organic-acid content were observed in silages with chicken (41%) and pig (15%) manure biogas slurries without solid-liquid separation, which was not the case for treatments with solid-liquid separation. During the ensiling process, more lignocellulose was degraded under the high buffer-capacity provided by the ammonia-nitrogen in the biogas slurry. An increase of 7.1%-9.6% was observed for the specific methane yield_measured, which offset a storage loss of 5.0%-7.3%. Ensiling EWMS with biogas slurry therefore provides a viable strategy for biogas production.

Keywords: Biogas production; Biogas slurry; Ensiling; Maize stover; Microbial community.