Question

During which step of wastewater treatment sterilization of water occurs?

• A. Aeration
• B. Coagulation
• C. Clariflocculation
• D. Chlorination

Answer 1

The correct option is D

Chlorination

Water treatment follows six steps: Aeration, coagulation, clariflocculation, filtration, chlorination and storage.

• Aeration- Oxygen is added to water.
• Coagulation- Alum is added due to which sedimentation of solid waste occurs. Then lime is added which regulates the pH by increasing it.
• Clariflocculation- Water is fed into filters.
• Filtration- Impurities are filtered out.
• Chlorination- Water is sterilised by adding chlorine tablets or bleaching powder.
• Storage- Purified water is stored.