1. Extracellular electron transfer and the conductivity in microbial aggregates during biochemical wastewater treatment: A bottom-up analysis of existing knowledge.
- Author
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Gu, Yuyi, Qi, Xiang, Yang, Xufei, Jiang, Yong, Liu, Panpan, Quan, Xiangchun, and Liang, Peng
- Subjects
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CHARGE exchange , *WASTEWATER treatment , *MASS transfer coefficients , *ELECTRICAL conductivity measurement , *ELECTRIC conductivity , *WASTE recycling , *MASS transfer - Abstract
• Conductivity is a comparable metric to characterize EET. • Nanowires and microbial aggregates have substantially different conductivity levels. • Several factors can cause a large variability in the measured conductivity. • Calculating the EET flux in microbial aggregates from conductivity measurement. Microbial extracellular electron transfer (EET) plays a crucial role in bioenergy production and resource recovery from wastewater. Interdisciplinary efforts have been made to unveil EET processes at various spatial scales, from nanowires to microbial aggregates. Electrical conductivity has been frequently measured as an indicator of EET efficiency. In this review, the conductivity of nanowires, biofilms, and granular sludge was summarized, and factors including subjects, measurement methods, and conducting conditions that affect the conductivity difference were discussed in detail. The high conductivity of nanowires does not necessarily result in efficient EET in microbial aggregates due to the existence of non-conductive substances and contact resistance. Improving the conductivity measurement of microbial aggregates is important because it enables the calculation of an EET flux from conductivity and a comparison of the flux with mass transfer coefficients. This review provides new insight into the significance, characterization, and optimization of EET in microbial aggregates during a wastewater treatment process. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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