Activated Sludge Process(Engineering > Waste Water Engineering ) Questions and Answers

Question 1. ________ is treated in activated sludge reactor.
  1.    Pre-treated sludge
  2.    Treated sludge
  3.    Macronutrients
  4.    Micro-organisms
Explanation:-
Answer: Option A. -> Pre-treated sludge
Answer: (a).Pre-treated sludge

Question 2. Why is the sludge aerated?
  1.    To avoid bacterial growth
  2.    To increase bacterial growth
  3.    To maintain pH
  4.    To maintain temperature
Explanation:-
Answer: Option B. -> To increase bacterial growth
Answer: (b).To increase bacterial growth

Question 3. After the treatment, the BOD demand ______
  1.    Remains constant
  2.    Decreases
  3.    Increases
  4.    Alters
Explanation:-
Answer: Option B. -> Decreases
Answer: (b).Decreases

Question 4. Which is the next reactor after activated sludge reactor in the treatment process?
  1.    Flocculation unit
  2.    Aeration unit
  3.    Clarifier
  4.    Disinfection unit
Explanation:-
Answer: Option C. -> Clarifier
Answer: (c).Clarifier

Question 5. Which type of pump is preferred to remove trickling filter humus?
  1.    Submersible cutter pump
  2.    Non-clog pump
  3.    Vertical turbine pumps
  4.    Diaphragm pump
Explanation:-
Answer: Option D. -> Diaphragm pump
Answer: (d).Diaphragm pump

Question 6. Which of these is not an alternative to activated sludge treatment systems?
  1.    Stabilization ponds
  2.    Rotating biological reactors
  3.    Trickling filter
  4.    Screening units
Explanation:-
Answer: Option D. -> Screening units
Answer: (d).Screening units

Question 7. Where is the sludge at the bottom of the clarifier processed to?
  1.    Settling unit
  2.    Aerator
  3.    Flocculation unit
  4.    Disinfection unit
Explanation:-
Answer: Option B. -> Aerator
Answer: (b).Aerator

Question 8. Which are the three ingredients in activated sludge systems?
  1.    Cells, sewage and oxygen
  2.    Cells, sewage and nitrogen
  3.    Solids, sewage and oxygen
  4.    Solids, water and oxygen
Explanation:-
Answer: Option A. -> Cells, sewage and oxygen
Answer: (a).Cells, sewage and oxygen

Question 9. How is air pumped in the aerator unit?
  1.    Bubbled from bottom
  2.    Sides
  3.    Bubbled from top
  4.    Sprayed
Explanation:-
Answer: Option A. -> Bubbled from bottom
Answer: (a).Bubbled from bottom

Question 10. An activated sludge system consists of two components, an aerator and ________
  1.    Screening units
  2.    Disinfection unit
  3.    Flocculation unit
  4.    Clarifier
Explanation:-
Answer: Option D. -> Clarifier
Answer: (d).Clarifier