Waste Water Engineering Mock Test 6

10%

Question 1 of 10

1. What is the volumetric organic loading in Kg COD/ m³ day for a completely mixed anaerobic digestion process?

9-12

5-7

1-5

7-9

Question 1 of 10

Question 2 of 10

2. Which of the following methods are not used for pathogen destruction?

Composting

Thermophilic digestion

Mechanical stirring

Incineration

Question 2 of 10

Question 3 of 10

3. The scum formed in the tank _____

Sink into the bottom

Gets dissolved

Flows

Floats on top

Question 3 of 10

Question 4 of 10

4. Calculate the tank volume for the Moving bed bioreactor system for the following data.
Flow: 800 m³/h.
BOD: 300 mg/L
Retention time: 6 hrs

10500 m³

4500 m³

6500 m³

4800 m³

Question 4 of 10

Question 5 of 10

5. What is the angle at which the plates should be inclined in a lamella clarifier?

70-80 degree

35-45 degree

20-35 degree

45-60 degree

Question 5 of 10

Question 6 of 10

6. How many steps are present in anaerobic digestion?

Question 6 of 10

Question 7 of 10

7. Calculate the flow per plate in a lamella clarifier for the following data?
Flow: 20m³/h
Area of plate: 1.2 m²
Rise rate: 1.2 m³/m²/h

1.66 m³/h

1.44 m³/h

1.04 m³/h

1.55 m³/h

Question 7 of 10

Question 8 of 10

8. Surfactants and finely divided solids _____the stability of the emulsion.

Neutralize

Nullify

Increase

Decease

Question 8 of 10

Question 9 of 10

9. What is the range of charge present on bentonite?

40-60 meq/gram

30-40 meq/gram

70-90 meq/gram

20-30 meq/gram

Question 9 of 10

Question 10 of 10

10. Sludge treatment aims at reducing sludge weight and volume.

False

True

Question 10 of 10