Investigation on the effect of different additives on anaerobic co-digestion of corn straw and sewage sludge: Comparison of biochar, Fe3O4, and magnetic biochar

Pengfei Li; Qi Wang; Xiaoman He; Ran Yu; Chao He; Dekui Shen; Youzhou Jiao

doi:10.1016/j.biortech.2021.126532

Investigation on the effect of different additives on anaerobic co-digestion of corn straw and sewage sludge: Comparison of biochar, Fe₃O₄, and magnetic biochar

Bioresour Technol. 2022 Feb:345:126532. doi: 10.1016/j.biortech.2021.126532. Epub 2021 Dec 9.

Authors

Pengfei Li¹, Qi Wang², Xiaoman He¹, Ran Yu¹, Chao He³, Dekui Shen⁴, Youzhou Jiao³

Affiliations

¹ Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, PR China.
² College of Metrology and Measurement Engineering, China Jiliang University, Hangzhou 310087, Zhejiang, PR China.
³ College of Mechanical and Electrical Engineering, Henan Agricultural University, Nongye Road 63, Zhengzhou, Henan 450002, PR China.
⁴ Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, PR China. Electronic address: 101011398@seu.edu.cn.

PMID: 34896538
DOI: 10.1016/j.biortech.2021.126532

Abstract

The co-digestion of corn straw and sewage sludge with different additives (biochar, magnetic biochar, Fe₃O₄) were investigated. The highest cumulative methane yield of 245.15 mL/g VS_added was obtained with the Fe₃O₄ addition ratio of 5 g/kg, which was 60.47% higher than that of the control run (without additives). The lag phase time was shortened from 5.46 to 3.82 days with a biochar dosage of 5 g/kg. The performance of Fe₃O₄ on methane production from the co-digestion process was better than that of the biochar and magnetic biochar. The direct interspecies electron transfer (DIET) was enhanced with regard to the increased concentration of acetic acid and decreased concentration of propionic acid. Microbial community analysis showed that the Geobacter and Methanosarcina were selectively enriched on the surface of Fe₃O₄, promoting the DIET and acetoclastic methanogenesis pathway. The cost-benefit analysis proved that the strategy of recycling Fe₃O₄ additive has the best economic benefit.

Keywords: Co-digestion; Cost-benefit analysis; Magnetic biochar; Methane production; Recycling.

MeSH terms

Anaerobiosis
Bioreactors
Charcoal
Digestion
Magnetic Phenomena
Methane
Sewage*
Zea mays*

Substances

Sewage
biochar
Charcoal
Methane