Keerthi et al. have reported 90 and 93% of reduction in chemical oxygen demand
and colour in tannery wastewater through hybrid membrane bioreactor (Keerthi et al.
2013). However, the severe fouling due to the plugging of several pollutants is the
main disadvantage of this process, but extensive research is in process to overcome
this issue, such as the integration of membrane bioreactors with another treatment
process will reduce the fouling and mineralize majority of the pollutants (Fazal et al.
2015).
11.6.3 Anaerobic Ammonium Oxidation
This process is also known as anammox technology, used to separate nitrogen from
wastewater, and compared to conventional nitrification and denitrification processes
anammox process consumes low energy, with high efficiency (Ali and Okabe 2015).
In the presence of nitrogen dioxide as an electron acceptor, this process transforms
ammonium cation to dinitrogen and produces 90% less sludge in comparison to
conventional nitrification and denitrification. This is a two-step process: in the first
step, oxidation of ammonium cation to nitrogen dioxide happens, and in the second
stage, ammonium cation oxidizes with nitrogen dioxide to form dinitrogen; afterwards, the process was introduced to single-stage reactor (Ali and Okabe 2015).
The anammox methodology was implemented by Anjali and Sabumon to remove
ammonia from tannery wastewater, which saved 90% of operational cost in sludge
discharge, and ingests 100% less organic carbon and 50% less oxygen (Anjali and
Sabumon 2014). Hence, for the industries having effluent of high ammonia concentration, anammox oxidation could be a good economic approach (Ali and Okabe
2015).
11.6.4 Advanced Oxidation Processes
The drawbacks of conventional treatment technologies encouraged the scientific
community to develop novel approaches towards efficient removal of contaminants
from wastewater generated through various industries. To this context, advanced
oxidation processes can fill the gap between the treatability limit of conventional
process and rigorously increasing limit of environmental regulations (Dewil et al.
2017).
Usually, advanced oxidation processes are applied after secondary treatment of
wastewater, and hence they are considered as tertiary treatment techniques
(Audenaert et al. 2011). Advanced oxidation processes are the inclusion of heterogeneous and homogeneous photocatalysis, ozonation, ultrasonication, electrochemical processes, Fenton process and wet oxidation processes (Dewil et al. 2017). The
main benefit of these processes is the effective degradation of pollutant without
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and colour in tannery wastewater through hybrid membrane bioreactor (Keerthi et al.
2013). However, the severe fouling due to the plugging of several pollutants is the
main disadvantage of this process, but extensive research is in process to overcome
this issue, such as the integration of membrane bioreactors with another treatment
process will reduce the fouling and mineralize majority of the pollutants (Fazal et al.
2015).
11.6.3 Anaerobic Ammonium Oxidation
This process is also known as anammox technology, used to separate nitrogen from
wastewater, and compared to conventional nitrification and denitrification processes
anammox process consumes low energy, with high efficiency (Ali and Okabe 2015).
In the presence of nitrogen dioxide as an electron acceptor, this process transforms
ammonium cation to dinitrogen and produces 90% less sludge in comparison to
conventional nitrification and denitrification. This is a two-step process: in the first
step, oxidation of ammonium cation to nitrogen dioxide happens, and in the second
stage, ammonium cation oxidizes with nitrogen dioxide to form dinitrogen; afterwards, the process was introduced to single-stage reactor (Ali and Okabe 2015).
The anammox methodology was implemented by Anjali and Sabumon to remove
ammonia from tannery wastewater, which saved 90% of operational cost in sludge
discharge, and ingests 100% less organic carbon and 50% less oxygen (Anjali and
Sabumon 2014). Hence, for the industries having effluent of high ammonia concentration, anammox oxidation could be a good economic approach (Ali and Okabe
2015).
11.6.4 Advanced Oxidation Processes
The drawbacks of conventional treatment technologies encouraged the scientific
community to develop novel approaches towards efficient removal of contaminants
from wastewater generated through various industries. To this context, advanced
oxidation processes can fill the gap between the treatability limit of conventional
process and rigorously increasing limit of environmental regulations (Dewil et al.
2017).
Usually, advanced oxidation processes are applied after secondary treatment of
wastewater, and hence they are considered as tertiary treatment techniques
(Audenaert et al. 2011). Advanced oxidation processes are the inclusion of heterogeneous and homogeneous photocatalysis, ozonation, ultrasonication, electrochemical processes, Fenton process and wet oxidation processes (Dewil et al. 2017). The
main benefit of these processes is the effective degradation of pollutant without
370
A. Tripathi and S. Narayanan