TY - JOUR
T1 - Enhanced stability of food waste anaerobic digestion under low inoculum to substrate ratio by using biochar
AU - Luo, Liwen
AU - Chu, Puiyan
AU - Liang, Jialin
AU - Davidraj, Johnravindar
AU - Zhao, Jun
AU - Wong, Jonathan W.C.
N1 - Funding Information:
The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China (51978595) and the Research Grants Council of the Hong Kong Special Administration Region, China (Code No. GRF 12203322).
Publisher Copyright:
© 2022 Informa UK Limited, trading as Taylor & Francis Group.
PY - 2022/12/28
Y1 - 2022/12/28
N2 - The influence of biochar on anaerobic digestion (AD) of organic waste have been widely studied. However, the effect of biochar on the mitigation of acidification and subsequently the stimulation of methanogenesis recovery during mono food waste (FW) digestion process under a low inoculum to substrate (I/S) ratio (i.e. a high organic loading) is rarely investigated. In this study, the benefit of biochar with respect to methane production from FW was explored in a mono FW AD system with four different additional amounts of biochar, i.e. 0, 5, 10 and 15 g/L. Results revealed that biochar boosted methane production in AD at a low I/S ratio by 390–530% through stimulating methanogenic activity, improving organics removal and enhancing process stability. The biochar dosage of 10 g/L demonstrated the highest biodegradability of 92.3% and the highest specific methane production of 553.0 mL/g VSremoved among all groups. Without biochar addition, volatile fatty acids (VFAs) accumulated to 20 g/L and the highest total ammonium-N (TAN) was > 1200 mg/L. The suppression of methanogenesis was significantly correlated with VFA and TAN (p < 0.05). Therefore, biochar addition presented a positive effect on VFAs degradation and buffering capacity which could be an effective approach to enhance methane production from FW digestion at a low inoculum to substrate ratio without the fear of system failure.
AB - The influence of biochar on anaerobic digestion (AD) of organic waste have been widely studied. However, the effect of biochar on the mitigation of acidification and subsequently the stimulation of methanogenesis recovery during mono food waste (FW) digestion process under a low inoculum to substrate (I/S) ratio (i.e. a high organic loading) is rarely investigated. In this study, the benefit of biochar with respect to methane production from FW was explored in a mono FW AD system with four different additional amounts of biochar, i.e. 0, 5, 10 and 15 g/L. Results revealed that biochar boosted methane production in AD at a low I/S ratio by 390–530% through stimulating methanogenic activity, improving organics removal and enhancing process stability. The biochar dosage of 10 g/L demonstrated the highest biodegradability of 92.3% and the highest specific methane production of 553.0 mL/g VSremoved among all groups. Without biochar addition, volatile fatty acids (VFAs) accumulated to 20 g/L and the highest total ammonium-N (TAN) was > 1200 mg/L. The suppression of methanogenesis was significantly correlated with VFA and TAN (p < 0.05). Therefore, biochar addition presented a positive effect on VFAs degradation and buffering capacity which could be an effective approach to enhance methane production from FW digestion at a low inoculum to substrate ratio without the fear of system failure.
KW - anaerobic digestion
KW - Biochar
KW - low inoculum to substrate ratio
KW - system stability
KW - VFA accumulation
UR - http://www.scopus.com/inward/record.url?scp=85145470234&partnerID=8YFLogxK
U2 - 10.1080/09593330.2022.2157759
DO - 10.1080/09593330.2022.2157759
M3 - Journal article
C2 - 36524382
AN - SCOPUS:85145470234
SN - 0959-3330
JO - Environmental Technology (United Kingdom)
JF - Environmental Technology (United Kingdom)
ER -
