Question

Which of the following is not correct regarding the primary treatment of waste-water?

• A. Initially floating debris is removed by distillation
• B. Grit and pebbles are removed by sedimentation
• C. Solids that settle form the primary sludge
• D. Supernatant forms the effluent

Answer 1

Answer:

A. Initially floating debris is removed by distillation

• In primary treatment, initially floating debris is removed by sequential filtration.

• Then grit and small pebbles are removed by sedimentation.

• All solids that settle form the primary sludge while the supernatant forms the effluent.