Bioelectrochemical Systems (BES) for Microbial Electroremediation: An Advanced Wastewater Treatment Technology - Applied Environmental Biotechnology: Present Scenario and Future Trends - page 159

requires large amount of wastewater and fresh
water, low current densities, pH, membrane in-
tegrity and fouling, and safety issues. Addressing
these issues with relevant investigations helps to
commercialize MDC as the technology (Kim and
Logan 2013 ; Ping et al. 2013 ).

hand, BES can also be integrated to the effluents
of conventional treatment process (rich in acid
metabolites) to generate value added chemicals
and solvents under small applied potential. Mul-
tiple advantages of BES are mainly limited by the
problems in upscaling, especially with the design
issues. Working in the direction of constructing
BES to treat large volumes and higher loading
rates is very important to make this technology
competitive to the existing conventional pro-
cesses.

10.7 Future Directions

Among the multifaceted applications of BES,
treatment of recalcitrant pollutants present in
wastewaters is quite interesting and already few
studies have been reported with synthetic as well
as real field substrates. The unique ability of
these systems to treat complex pollutants, which
are difficult to treat in conventional processes, is
based on the integrated function of microbial me-
tabolism with electrochemistry in a single reac-
tor. Important fact is that the application of BES
for the removal of toxic pollutants and xenobiot-
ics is currently being extensively studied to en-
hance the treatment efficiency. Experiments with
real-field wastewater differs a lot compared to the
synthetic pollutants, especially in terms of energy
recovery. Application of BES for the treatment of
real-field wastewater should be more focused,
considering the energy recovery as one of the ob-
jective, to make the system/process economically
viable. Treatment of petroleum based chemicals
such as aromatic hydrocarbons and pharmaceu-
tical based wastewater are some of the burning
problem of the industrial sector. Application of
BES to treat complex structures to simple carbon
chains (breaking aromatic rings) would be very
interesting. Similarly, application of BES for the
treatment of solid wastes such as kitchen-based,
vegetable, slaughter house, municipal etc., would
be very innovative and reduces the pretreatment
costs. Treatment of chlorinated aliphatic hy-
drocarbons such as trichloroethene (TCE) and
perchloroethylene, widely used solvents and
degreasing agents, is also being studied by few
researchers in BES. Detailed studies towards
complete elimination of these highly toxic sub-
stances (carcinogenic also) from being disposed
into soil and groundwater by treating them in
BES would be highly interesting. On the other

Acknowledgements Gunda Mohanakrishna gratefully
acknowledges the Marie-Curie Intra-European Fellow-
ship (IEF) supported project BIO-ELECTRO-ETH-
YLENE (Grant No: 626959) and Sandipam Srikanth
gratefully acknowledges the Marie-Curie International
Incoming Fellowship (IIF) supported project ELECTRO-
ENZEQUEST (Grant No: 330803) from the European
Commission.

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