Effect of microaeration combined with ferric chloride pretreatment on anaerobic digestion of corn stalk

ABSTRACT

In this study, microaeration combined with ferric chloride pretreatment was used to improve the methanogenic performance for thermophilic dry anaerobic digestion. Parameter optimization and mechanism analysis were explored for combined pretreatment in anaerobic digestion by response surface methodology and microbial diversity and community. The results showed that both microaeration and ferric chloride had significant effects on the cumulative methane production, and the effect of microaeration was greater than that of ferric chloride. The optimal pretreatment parameters were predicted at oxygen loading rate of 0.76 mL/g VS and ferric chloride addition rate of 4.04 mg/g VS. The methane production of anaerobic digestion was 114.05 mL/g VS with the optimal pretreatment parameters, which was 17.78% higher than that without pretreatment. In addition, microbial community analysis showed that combined pretreatment enhanced methanogenesis by enhancing the hydrogenotrophic pathway.

KEYWORDS:

• Anaerobic digestion
• pretreatment
• methane production
• microbial community
• corn stalk

Acknowledgments

This study was supported by the Heilongjiang Provincial Natural Science Foundation of China (ZD2019F002), the Postdoctoral Funding of Heilongjiang Province of China (LBH-Z19087), the Key Project from Heilongjiang Provincial Reclamation General Administration (HKKYZD190805), the Heilongjiang Bayi Agricultural University Support Program for San Heng San Zong (ZRCQC202007).

Disclosure statement

No potential conflict of interest was reported by the author(s).