Question

The treatment which employs mechanical and hydraulic separation principles is known as

• A. Primary treatment
• B. Secondary treatment
• C. Tertiary treatment
• D. Aeration process

Hint:

Treatment stages:
• Primary $\rightarrow$ Physical separation.
• Secondary $\rightarrow$ Biological treatment.
• Tertiary $\rightarrow$ Advanced treatment.

Answer 1

The Correct Option is A

Concept: Wastewater treatment is generally carried out in three stages:
• Primary treatment
• Secondary treatment
• Tertiary treatment Primary treatment removes suspended solids by physical processes such as screening, grit removal and sedimentation. It mainly employs mechanical and hydraulic separation.

Step 1: Understand primary treatment. Primary treatment consists of
• Screening
• Grit chambers
• Primary sedimentation tanks These units remove floating and settleable solids without biological action.

Step 2: Identify the treatment stage. Since only mechanical and hydraulic separation are involved, \[ \boxed{\text{Primary treatment}} \] is the correct answer. Therefore, the correct option is \[ \boxed{(A)\;\text{Primary treatment}.} \]