The GATE Grind

GATE 2026 CE (CE2) – Question 29

Water and Waste Water Quality and Treatment · Primary, secondary and tertiary treatment, effluent standards · 1 mark · Multiple choice

The grown algae are useful in the operation of

  1. oxidation pond.
  2. slow sand filter.
  3. cyclone separator.
  4. septic tank.

Practise this question in The GATE Grind →

Show answer and explanation

Correct answer: (A) oxidation pond.

Explanation

In an oxidation pond algae use sunlight to photosynthesise and release the oxygen that the bacteria need to break down the organic matter. In a slow sand filter algae only clog the surface, a cyclone separator is an air-pollution device, and a septic tank works without air.