state gov Maharashtra Town Planning Assistant (TPA) Test Series 2024 Environmental Engineering Sewage Sewage Treatment
Which of the following statements about the secondary treatment of sewage is INCORRECT?
1
Oxidation of organic matter occurs in trickling filters under aerobic conditions.
2
Secondary treatment methods are broadly divided into filtration and activated sludge process.
3
Activated sludge is biologically active.
4
Primary treatment of sewage is not essential for efficient working of contact beds.