Explore topic-wise MCQs in Waste Water Engineering.

This section includes 23 Mcqs, each offering curated multiple-choice questions to sharpen your Waste Water Engineering knowledge and support exam preparation. Choose a topic below to get started.

1.

Determine the surface area with recycle for the following information.A/S = 0.008 mL/mgTemperature: 20 degree CelsiusAir solubility: 18.7 mL/LRecycle steam pressure: 275 kPaFraction of saturation: 0.5Surface Loading rate: 8 L/m2/minSludge flow rate: 400 m3/d

A. 40.1 m2
B. 47.7 m2
C. 38 m2
D. 72 m2
Answer» B. 47.7 m2
2.

Compute the required recycled rate for the flotation thickener with recycle for the following information:A/S = 0.008 mL/mgp = 275 atmTemperature: 20 degree CelsiusAir solubility: 18.7 mL/LRecycle steam pressure: 275 kPaFraction of saturation: 0.5Surface Loading rate: 8 L/m2/minSludge flow rate: 400 m3/d

A. 462 m3/d
B. 642 m3/d
C. 380 m3/d
D. 680 m3/d
Answer» B. 642 m3/d
3.

Determine the surface area for the following information.A/S = 0.008 mL/mgTemperature: 20 degree CelsiusAir solubility: 18.7 mL/LRecycle steam pressure: 275 kPaFraction of saturation: 0.5Surface Loading rate: 8 L/m2/minSludge flow rate: 400 m3/d

A. 34.7 m2
B. 67.7 m2
C. 38 m2
D. 72 m2
Answer» B. 67.7 m2
4.

Compute the required pressure for the flotation thickener without recycle for the following information:A/S = 0.008 mL/mgTemperature: 20 degree CelsiusAir solubility: 18.7 mL/LRecycle steam pressure: 275 kPaFraction of saturation: 0.5Surface Loading rate: 8 L/m2/minSludge flow rate: 400 m3/d

A. 302 kPa
B. 640 kPa
C. 380 kPa
D. 680 kPa
Answer» B. 640 kPa
5.

What is the range of charge present on bentonite?

A. 20-30 meq/gram
B. 30-40 meq/gram
C. 40-60 meq/gram
D. 70-90 meq/gram
Answer» E.
6.

Organo clays are manufactured by modifying _____with quaternary amines.

A. Nitrogen
B. Bentonite
C. Potassium
D. Sodium
Answer» C. Potassium
7.

Surfactants and finely divided solids _____the stability of the emulsion.

A. Increase
B. Decease
C. Neutralize
D. Nullify
Answer» B. Decease
8.

An emulsion is a _____ system.

A. Homogenous
B. Heterogenous
C. Natural
D. Oxidized
Answer» C. Natural
9.

_________ act as a coupling agent between oil oil/water phases.

A. Oil
B. Water
C. Emulsifier
D. Disinfectants
Answer» D. Disinfectants
10.

AN_EMULSION_IS_A_______SYSTEM.?$

A. Homogenous
B. Heterogenous
C. Natural
D. Oxidized
Answer» C. Natural
11.

Organo clays are manufactured by modifying _____with quaternary amines.$

A. Nitrogen
B. Bentonite
C. Potassium
D. Sodium
Answer» C. Potassium
12.

Surfactants_and_finely_divided_solids______the_stability_of_the_emulsion.$

A. Increase
B. Decease
C. Neutralize
D. Nullify
Answer» B. Decease
13.

What is the velocity considered for a flotation thickener to remove oil?

A. 8 L/m<sup>2</sup>/min -160 L/m<sup>2</sup>/min
B. 180 L/m<sup>2</sup>/min
C. 200 L/m<sup>2</sup>/min-250 L/m<sup>2</sup>/min
D. 2 L/m<sup>2</sup>/min-8 L/m<sup>2</sup>/min
Answer» B. 180 L/m<sup>2</sup>/min
14.

The design of oil/water separators is based on _________

A. Stoke’s law
B. Newton’s law
C. Boyle’s law
D. Charles’s law
Answer» B. Newton‚Äö√Ñ√∂‚àö√ë‚àö¬•s law
15.

What_is_the_range_of_charge_present_on_bentonite?

A. 20-30 meq/gram
B. 30-40 meq/gram
C. 40-60 meq/gram
D. 70-90 meq/gram
Answer» E.
16.

_________ act as a coupling agent between oil oil/water phases?

A. Oil
B. Water
C. Emulsifier
D. Disinfectants
Answer» D. Disinfectants
17.

What is the size of dissolved oil droplets?

A. Less than 10 microns
B. Less than 8 microns
C. Less than 7 microns
D. Less than 5 microns
Answer» E.
18.

What is the colour of the emulsion?

A. White
B. Grey
C. Black
D. Yellow
Answer» B. Grey
19.

What is the size of the oil droplets?

A. Less than 50 microns
B. Less than 40 microns
C. Less than 30 microns
D. Less than 20 microns
Answer» E.
20.

The lipophilic end ______

A. Remains in water
B. Enters oil droplet
C. Dissolves
D. Stays on top of water surface
Answer» C. Dissolves
21.

Lipophilic end is water liking.

A. True
B. False
Answer» C.
22.

The surfactants have ______ chains.

A. Linear
B. Hydrocarbon
C. Complex
D. Carbon
Answer» C. Complex
23.

Oil and grease is the presence of inorganics in wastewater.

A. True
B. False
Answer» C.