Multiple choice

Which of the following come under secondary treatment systems of waste water?

  1. Sedimentation
  2. Trickling filters
  3. Activated sludge
  4. Phosphorus removal Select the correct answer.

  1. 1 and 2

  2. 1 and 3

  3. 2 and 3

  4. 3 and 4

  5. All of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Secondary treatment systems are classified as: Fixed-film or attached growth systems: It includes trickling filters, biotowers, and rotating biological contactors, where the biomass grows on media and the sewage passes over its surface. Suspended-growth systems: It include activated sludge, where the biomass is mixed with the sewage and can be operated in a smaller space than trickling filters that treat the same amount of water.

Keep practicing — related questions