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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. | |