Conductive Materials Enhance Performance of Anaerobic Membrane Bioreactor in Treating Liquid Waste from Animal Farming: a Review

Purpose of ReviewAnaerobic membrane bioreactor (AnMBR) holds considerable promise for the recovery and reutilization of resources from animal farming liquid waste (AFLW). However, typical pollutants in AFLW can markedly impair AnMBR performance. This review aims to describe the mechanisms through which conductive materials enhance AnMBR performance to maximize resource recovery and minimize environmental impact.Recent FindingsAFLW exhibits high resource utilization potential. However, pollutants in AFLW, such as antibiotics, resistance genes, and heavy metals (HMs), can disrupt microbial communities in AnMBR, reducing treatment efficiency and increasing environmental risks. Conductive materials, such as iron-based materials (e.g., zero-valent iron, magnetite) and carbon-based materials (e.g., biochar, granular activated carbon), enhance microbial activity through mediated interspecies electron transfer and direct interspecific electron transfer, improving pollutant removal and resource recovery. Additionally, conductive materials reduce the bio-toxicity of HMs through adsorption, further mitigating environmental pollution.SummaryThis review highlights the enhancement of resource recovery and reduction of environmental risks in AnMBR for treating AFLW through the incorporation of conductive materials. The incorporation of conductive materials has been shown to significantly improve AnMBR performance, including enhanced methane production, reduced start-up time, and improved degradation efficiency of organic matter. The main mechanisms of conductive materials are further discussed to provide the further development of AnMBR in AFLW treatment.