Question

After a significant reduction in the BOD of wastewater, it is passed into a settling tank where bacterial flocs are allowed to sediment. This sediment is called ______.

Options

• primary sludge

• activated sludge

• effluent

• grit

Answer 1

After a significant reduction in the BOD of wastewater, it is passed into a settling tank where bacterial flocs are allowed to sediment. This sediment is called activated sludge.

Explanation:

Following a significant drop in the BOD of wastewater during sewage treatment, it is fed into a settling tank where bacterial flocs are permitted to sediment. This sediment is referred to as activated sludge.