‘‘Micro-organisms play an important role for the biological treatment of sewage.’’ Justify.
We know that secondary treatment of sewage is also called biological treatment as it involves biological organisms such as aerobic and anaerobic microbes and fungi for digestion of organic waste.
Microbes play a significant role during secondary and tertiary sewage treatment. During secondary treatment, primary effluent is continuously agitated in a large tank due to which vigorous growth of useful aerobic microbes into flocs takes place.