Question

What are the sediments in the settling tanks of tertiary treatment in STP called?

• A. Activated Sludge
• B. Contaminants
• C. Effluents
• D. Sewage

Hint:

Activated sludge is rich in microorganisms that break down organic matter, essential for the final stages of water purification in STP.

Answer 1

The Correct Option is A

Step 1: Understanding the STP process.
In sewage treatment plants (STP), after primary and secondary treatment, the sediments collected in tertiary treatment are referred to as activated sludge. This sludge contains microorganisms that help break down organic matter.
Step 2: Analyzing the options.
(A) Activated Sludge: Correct, activated sludge is the result of microorganisms in the tertiary treatment stage.
(B) Contaminants: Incorrect, contaminants are removed during the treatment process, not collected as sediments.
(C) Effluents: Incorrect, effluents are the treated liquid released after the treatment process.
(D) Sewage: Incorrect, sewage is the raw waste entering the treatment plant, not the sediments.
Step 3: Conclusion.
The correct answer is (A) Activated Sludge, as it refers to the sediments collected during tertiary treatment.