Q23. Which of the following is put into Anaerobic sludge digester for further sewage treatment?

Solution:
When BOD of sewage has reduced, the effluent is passed into settling tank. Here, the bacterial flocs settle, and the sediment is called activated sludge. A small part of the sludge is used as an inoculum in the aeration tank and the remaining part is passed into large tanks called anaerobic sludge digesters.