In recent years Bioelectrochemical systems (BESs) as a new approach
represent an energy-efficient way for wastewater treatment, metal/nutrient recovery,
and transformation of wastes to valuable products such as hydrogen. These unique
characteristics of BESs are provided by a flexible platform for oxidation-reduction
reactions. Although this process is still not fully developed but it can be nominated as a
future trend of green energy and cleaner biochemical production pathway along with
the waste remediation. Conversion of organic wastes into electricity and
hydrogen/chemical products occurs in microbial fuel cells (MFCs) and microbial
electrolysis cells (MECs), respectively. Different aspects of the process such as
biological communities, physical configuration, and electrochemical conditions can
affect a good performance of BES. In the present chapter review, the different
fundamental mechanisms of BESs with emphasis on nitrogen removal have been
reviewed. The behavior of affecting parameters on nitrogen and organic removal was
discussed, including content pH, electrode material, level of supernatant concentration,
the distance between electrodes and applied current, salinity and other operating
conditions. Moreover, reported pathways and the theory of denitrification in BESs were
described. Considering the finding, BES can be nominated as an alternative technology
to the minimization of waste and a good way to generate electrical energy and valuable
chemicals.
Keywords: Bioelectrochemical system, Denitrification, Electron donor, Electron
acceptor, Microbial Fuel Cell, Nitrate, Nitrogen, Wastewater.
