Wastewater treatment and energy production by microbial fuel cells

Abstract

The increasing demands of efficient and sustainable energy generation methods from waste products have taken a giant leap in the last century, and especially in the previous two decades. Wastewater treatment has also been a much-researched topic in recent years owing to the exponential increase in effluent-laden wastewater from industries, the agricultural sector and food sector, and its effects on the environment. There have been plenty of wastewater treatment techniques over the years, but most of them lack in terms of cost-effectiveness, durability, and energy recovery rates. Microbial fuel cells can prove to be of great use to tackle both of these issues in one go, as they perform bioelectrochemical processes on organic biodegradable compounds to oxidize them to generate power which can be harnessed by various means. This article explains the aim, construction, mechanism, and application of microbial fuel cells; the economic and scientific challenges that they face in the future; and microbial fuel cell (MFC) hybrid systems which make use of MFCs combined with other useful technologies for greater aims and better efficiencies. It overall discusses the various ways in which MFCs outperform other wastewater treatment technologies by significantly decreasing sludge production and being environment-friendly, and also some limitations and drawbacks that MFCs face owing to the fact that they are relatively newer technologies and still require decades of modifications until they reach excellent output rates. MFCs are known not only for wastewater treatment but also for contaminant removal, heavy metal removal, biohydrogen production, applications in biosensors, etc., as also discussed in this article.