Insights of enhancing methane production under high-solid anaerobic digestion of wheat straw by calcium peroxide pretreatment and zero valent iron addition

Wenjing Tian, Jianhao Li, Lirong Zhu, Wen Li, Linyan He, Li Gu, Rui Deng, Dezhi Shi, Hongxiang Chai and Meng Gao

Renewable Energy, 2021, vol. 177, issue C, 1321-1332

Abstract: Recent investigations verified CaO2 accelerated hydrolysis of lignocellulose, but its residue caused a harmful oxidizing environment. This study therefore proposed the combined CaO2 pretreatment and zero-valent iron (ZVI) addition to enhance high-solid anaerobic digestion of wheat straw, trying to eliminate negative effect of residual oxides. Effects of CaO2 pretreatment without/with ZVI addition on digestion performance were investigated. Results showed that in non-ZVI added digesters, as CaO2 dosage increased, total production of SCOD and VFAs increased linearly, while activities of coenzyme F420 and electron transport system were negatively correlated. Pretreatment using appropriate CaO2 dosage indirectly increased biogas production by promoting hydrolysis and acidification. Comparably, initial ORP in ZVI-added digesters sharply declined below −350 mV, which was suitable for methanogen growth. ZVI significantly improved activities of cellulase, hemicellulase, acetic kinase and coenzyme F420, with the highest improvement percentages of 138%, 48%, 35% and 58%, respectively. Since ZVI could provide electrons for conversion of CO2 to CH4, compared with non-ZVI added digesters (R0-R4), methane content in ZVI-added digesters (RZ0-RZ4) increased by 8.1%, 9.0%, 11.2%, 17.0% and 18.0% successively. Consequently, 0.6 g/g VS CaO2 pretreatment combined with 0.4 g/g VS ZVI addition achieved the maximum methane production, increasing by 35.6% compared to control digester.

Keywords: Anaerobic digestion; Wheat straw; Calcium peroxide; Zero valent iron (search for similar items in EconPapers)
Date: 2021
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (6)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0960148121009083
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:renene:v:177:y:2021:i:c:p:1321-1332

DOI: 10.1016/j.renene.2021.06.042

Access Statistics for this article

Renewable Energy is currently edited by Soteris A. Kalogirou and Paul Christodoulides

More articles in Renewable Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().