Write the first step the primary effluent undergoes when it enters the secondary treatment plant and state the purpose.

The plant undergoes wilting when

Flocs produced in the secondary treatment plant of the sewage comprises of,

In a sewage treatment plant, primary treatment is

Given below are the steps involved in sewage treatment. Arrange them in proper sequence and select the correct option. A. Passage of primary effluent into large aeration tanks for mechanical agitation and pumping of air. B. Passage of secondary effluent and formation of activated sludge. C. Physical removal of particles through filtration and sedimentation D. Release of effluent from the secondary treatment plant into natural water bodies. E. Growth of useful aerobic microbes into flocs which significantly reduce the BOD.

What are floes? State their role in effluent treatment and their ultimate fate in sewage treatment tank.

_______is the first step of sewage treatment.