Enhancing anaerobic digestion through the integration of microbial electrolysis cells: A comprehensive review

Anaerobic digestion is a great approach in recovering sustainable bioenergy from complex organic matters. However, many constrains have limited the application of the digester, like systems instability and inhibition of methane producing microbes due to the accumulation of Volatile Fatty Acids (VFAs) causing system's pH to drop drastically. Systems instability could be tackled by adding additives to improve the digester's performance and integrating microbial electrolysis cell with the digester to provide system's stability while maintaining high biogas production. Microbial community are the driving force in the conventional and hybrid system, altering the microbial community could improve the substrate degradation and selectivity of the biogas produced. This review discusses the microbial community in the anaerobic digester and hybrid system, in terms of the effect of inoculum source, biofilm and microbial suspension community, altering the microbial community for biogas production selectivity, effect of applied voltage and electrodes choice on the hybrid system. Ultimately, these findings hold the potential to benefit society by offering innovative solutions to enhance bioenergy production efficiency and addressing environmental challenges associated with organic waste management.