Once the BOD of waste water is reduced, it is passed into a ………………….
A. settling tank
B. primary sedimentation tank
C. anaerobic sludge digesters
D. aeration tank
Answer:A
Once the BOD of waste water is reduced, it is passed into a ………………….
A. settling tank B. primary sedimentation tank C. anaerobic sludge digesters D. aeration tank