Question

Sludge formation is a part of _________ process in the wastewater treatment plant.

• A. primary treatment
• B. secondary treatment
• C. screening
• D. aeration

Answer 1

The correct option is A primary treatment

Sludge refers to solids like faeces, that settle at the bottom of large settlement tanks, during primary treatment of water. Screening removes large objects like plastic bottles before primary treatment is done. Aeration is a part of secondary treatment, in which, air is pumped so that aerobic bacteria can grow and consume remaining human waste, food.