plastic media are highly preferred lately as they are easier to work with, provide taller
structures, and can be manipulated to have much greater surface for microbial
growth per volume of filter.
7.5.3 Membrane Bioreactor (MBR)
Membrane bioreactor has been in extensive usage for treatment of domestic waste,
but for industrial wastewater treatment applications, its use has been limited or
selective (Mittal 2011). MBR draw water from the mixed liquor into hollow fiber
membranes submerged in the activated sludge aeration tank, thus avoiding the need
for secondary clarifier in the conventional activated sludge process (Master and Ela
1991).
7.5.4 Bioremediation
Bioremediation is a branch of biotechnology that makes use of microorganism such
as microbes and bacteria to clean up the contaminants, pollutants, and toxins from
soil and water. In other words, it is a technology for removing pollutants from the
environment, thus preventing the degradation of original natural surroundings and
further reducing the pollution (Sasikumar and Papinazath 2003). Various microbes
participate in the remedial process, and cleaning up of waste is highly depending on
potential microbial action. Depending on the site where wastes are removed, it can
be categorized as ex situ and in situ.
7.5.4.1 Ex Situ
It is a process of withdrawal or removal of polluted soil from ground.
Land Farming
Land farming is considered as one of the simplest techniques due to its low cost and
lesser requirements of operational equipment. It allows effective removal of nearly
all the constituents. Contaminated soil is removed and spread on the ground surface
where the breakdown of constituents takes place by indigenous microbial activity.
7 Natural Biological Treatment of Effluent and Sludges to Combat the Burden of. . .
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