Effects of long-term acclimatization on the optimum substrate mixture ratio and substrate to inoculum ratio in anaerobic codigestion of food waste and cow manure

Bao-Shan Xing; Yule Han; Sifan Cao; Xiaochang C Wang

doi:10.1016/j.biortech.2020.123994

Effects of long-term acclimatization on the optimum substrate mixture ratio and substrate to inoculum ratio in anaerobic codigestion of food waste and cow manure

Bioresour Technol. 2020 Dec:317:123994. doi: 10.1016/j.biortech.2020.123994. Epub 2020 Aug 11.

Authors

Bao-Shan Xing¹, Yule Han¹, Sifan Cao¹, Xiaochang C Wang²

Affiliations

¹ International Science and Technology Cooperation Center for Urban Alternative Water Resources Development, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Engineering Technology Research Center for Wastewater Treatment and Reuse, Shaanxi, China; Key Laboratory of Environmental Engineering, Shaanxi, China; Xi'an University of Architecture and Technology, No. 13 Yanta Road, Xi'an 710055, China.
² International Science and Technology Cooperation Center for Urban Alternative Water Resources Development, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Engineering Technology Research Center for Wastewater Treatment and Reuse, Shaanxi, China; Key Laboratory of Environmental Engineering, Shaanxi, China; Xi'an University of Architecture and Technology, No. 13 Yanta Road, Xi'an 710055, China. Electronic address: xcwang@xauat.edu.cn.

PMID: 32836034
DOI: 10.1016/j.biortech.2020.123994

Abstract

The effects of long-term acclimatization on the optimum food waste to cow manure ratio (FW/CM) and substrate to inoculum ratio (S/I) in anaerobic codigestion with FW and CM were investigated by batch trials. For the unacclimated sludge, the highest CH₄ yields of 646.6 and 653.4 mL/g VS were achieved under the optimum FW/CM (2.5 VS/VS) and S/I (0.07 VS/VS) ratios, respectively. After more than 550 days of acclimatization, the optimum FW/CM and S/I of the acclimated sludge were improved to 3.4 and 0.68 VS/VS with more anaerobic digestion enzymes and lignocellulose, respectively. Based on high-throughput sequencing analysis, the microbial community structures of bacteria, fungi, and archaea were changed, which was the main reason for the change in the optimum FW/CM and S/I. Therefore, the FW/CM and S/I should be periodically optimized during the long-term operation of codigestion to improve the codigestion efficiency for biogas production.

Keywords: Acclimatization; Cow manure; FW/CM; Food waste; Substrate to inoculum ratio.

MeSH terms

Acclimatization
Anaerobiosis
Animals
Biofuels
Bioreactors
Cattle
Female
Food
Manure*
Methane
Refuse Disposal*

Substances

Biofuels
Manure
Methane