Bioaugmentation in waste water treatment

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Bioaugmentation is the practice of adding cultured microorganisms into the subsurface for the purpose of biodegrading specific soil and groundwater contaminants. In many cases, cultured microorganisms used for bioaugmentation are “specialists” in degrading specific target contaminants. For example, some microbes may be able to degrade the chlorinated compounds cis-1,2 dichloroethylene (cDCE) and vinyl chloride (VC) more quickly than the naturally-occurring microbial community at a particular site. As a result, the remediation community has shifted toward a more prescriptive approach with the use of bioaugmentation to accelerate the reductive dechlorination process, achieve remediation targets, and realize cost savings.



Bioaugmentation is commonly used in municipal wastewater treatment to restart activated sludge bioreactors. Most cultures available contain microbial cultures, already containing all necessary microorganisms(B.licheniformis, B.thuringiensis, P.polymyxa, B.stearothermophilus, Penicillium sp., Aspergillus sp., Flavobacterium, Arthrobacter, Pseudomonas, Streptomyces, Saccharomyces, etc.). Activated sludge systems are generally based on microorganisms like bacteria, protozoa, nematodes, rotifers, and fungi, which are capable of degrading biodegradable organic matter. There are many positive outcomes from the use of bioaugmentation, such as the improvement in efficiency and speed of the process of breaking down substances and the reduction of toxic particles in an area.

An example of how bioaugmentation has improved an environment, is in the coke plant wastewater in China. Coal in China is used as a main energy source and the contaminated water contains harmful toxic contaminants like ammonia, thiocyanate, phenols and other organic compounds, such as mono- and polycyclic nitrogen-containing aromatics, oxygen and sulfur-containing heterocyclics and polynuclear aromatic hydrocarbons. When indigenous heterotrophic microorganisms were added, they converted many large molecular compounds into smaller and simpler compounds, which could be taken from more biodegradable organic compounds. This proves that bioaugmentation could be used as a tool for the removal of unwanted compounds that are not properly removed by conventional biological treatment system. When bioaugmentation is combined with A1–A2–O system for the treatment of coke plant wastewater it is very powerful.

References:

https://en.wikipedia.org/wiki/Bioaugmentation

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