Chemically and biologically driven carbon transformation flow in MSW leachate treated by a high-solids anaerobic membrane bioreactor system

Zhiyue Wu; Wei Qiao; Yu-You Li; Junqiang Yao; Yibo Sun; Renjie Dong

doi:10.1016/j.chemosphere.2023.139075

Chemically and biologically driven carbon transformation flow in MSW leachate treated by a high-solids anaerobic membrane bioreactor system

Chemosphere. 2023 Sep:335:139075. doi: 10.1016/j.chemosphere.2023.139075. Epub 2023 May 30.

Authors

Zhiyue Wu¹, Wei Qiao², Yu-You Li³, Junqiang Yao¹, Yibo Sun¹, Renjie Dong⁴

Affiliations

¹ College of Engineering, China Agricultural University, China; Sanya Institute of China Agricultural University, Sanya, Hainan Province, 572025, China.
² College of Engineering, China Agricultural University, China; Sanya Institute of China Agricultural University, Sanya, Hainan Province, 572025, China. Electronic address: qiaowei@cau.edu.cn.
³ Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aoba, Aramaki-Aza, Sendai, Miyagi, 980-8579, Japan.
⁴ College of Engineering, China Agricultural University, China.

PMID: 37263509
DOI: 10.1016/j.chemosphere.2023.139075

Abstract

Carbon transformation is important for an anaerobic process but is often overlooked when using an anaerobic membrane bioreactor (AnMBR). Material flow in an AnMBR treating calcium-rich MSW leachate was thus quantitatively investigated to illustrate how chemical and biological factors affect carbon transformation. The results show that a remarkable amount of carbon in the leachate was degraded, with 50.1% of it should be converted into CH₄ and 37.7% of it into CO₂. However, a much smaller value of 40.6% and 14.2% were experimentally obtained. Chemical analysis indicated that the precipitation of calcium carbonate captured 1.23 g/day of carbon. At the same time, about 23.2 g/L HCO₃^- and 16.6 mg/L CH₄ (both as carbon) were dissolved in the liquid. Those features facilitated the high CH₄ (74%) content in biogas. A carbon transformation model was therefore established and showed carbon flow into the gas, liquid, and solid phases, respectively. Carbon existed in biogas, permeate, and discharged sludge was also obtained.

Keywords: Anaerobic digestion; Anaerobic membrane bioreactor; Carbon material flow; Chemical precipitation; MSW leachate.

MeSH terms

Anaerobiosis
Biofuels*
Bioreactors
Carbon*
Methane / metabolism
Sewage / chemistry

Substances

Carbon
Biofuels
Sewage
Methane