Environmental Engineering 17

Objective Questions and Answers of Civil Engineering: Environmental Engineering 17

Subject: Environmental Engineering 17

Part 17: Objective questions and answers of Environmental Engineering

 

Q1. Dissolved oxygen in streams is

a) Maximum at noon

b) Minimum at noon

c) Maximum at midnight

d) Same throughout the day

 

Q2. For satisfactory working of a sludge digestion unit, the ph range of digested sludge should be maintained as

a) 4.5 to 6.0

b) 6.5 to 8.0

c) 8.5 to 10.0

d) 10.5 to 12.0

 

Q3. The detention period for oxidation ponds is usually kept as

a) 4-8 hours

b) 24 hours

c) 10 to 15 days

d) 3 months

 

Q4. Sewage treatment units are designed for

a) Maximum flow only

b) Minimum flow only

c) Average flow only

d) Maximum and minimum flow

 

Q5. Which of the following unit works in anaerobic conditions?

a) Sludge digestion tank

b) Sedimentation tank

c) Activated sludge treatment

d) Trickling filters

 

Q6. Corrosion in concrete sewers is caused by

a) Septic conditions

b) Dissolved oxygen

c) Chlorine

d) Nitrogen

 

Q7. The means of access for inspection and cleaning of sewer line is known as

a) Inlet

b) Manhole

c) Drop manhole

d) Catch basin

 

Q8. The working conditions in imhoff tanks are

a) Aerobic only

b) Anaerobic only

c) Aerobic in lower compartment and anaerobic in upper compartment

d) Anaerobic in lower compartment and aerobic in upper compartment

 

Q9. Generally the detention period for grit chambers is kept as

a) 1 minute

b) 5 minutes

c) 2-4 hours

d) 12 hours

 

Q10. The main disadvantage of oxidation pond is that

a) Large area is required for construction

b) Maintenance and operation cost are high

c) Bod removal is very low

d) None of the above

 

Q11. Sludge volume index is defined as the ratio of

a) Percentage of sludge by volume to percentage of suspended solids by weight

b) Percentage of sludge by volume to percentage of total solids by weight

c) Percentage of suspended solids by weight to percentage of sludge by volume

d) Percentage of total solids by weight to percentage of sludge by volume

 

Q12. The biochemical treatment of sewage effluents is essentially a process of

a) Oxidation

b) Dehydration

c) Reduction

d) Alkalinization

 

Q13. For the same solid content, if the quantity of sludge with moisture content of 98% is x, then the quantity of sludge with moisture content of 96% will be

a) X/4

b) X/2

c) X

d) 2x

 

Q14. The gas from sludge digestion tank is mainly composed of

a) Nitrogen

b) Carbon dioxide

c) Hydrogen sulphide

d) Methane

 

Q15. In the two-pipe system of house plumbing, the pipes required are

a) One soil pipe, one waste pipe and one vent pipe

b) One soil pipe, two waste pipes and one vent pipe

 

Q16. When there is no recirculation of sewage, then recirculation factor is

a) 0

b) 1

c) Infinity

d) None of the above

 

Q17. Most of the bacteria in sewage are

a) Parasitic

b) Saprophytic

c) Pathogenic

d) Anaerobic

 

Q18. Facultative bacteria are able to work in

a) Presence of oxygen only

b) Absence of oxygen only

c) Presence as well as in absence of oxygen

d) Presence of water

 

Q19. Sewerage system is designed for

a) Maximum flow only

b) Minimum flow only

c) Average flow only

d) Maximum and minimum flow

 

Q20. Laying of sewers is usually done with the help of

a) A theodolite

b) A compass

c) Sight rails and boning rods

d) A plane table

 

Part 17: Objective questions and answers of Environmental Engineering

 

Q1. Answer a

 

Q2. Answer b

 

Q3. Answer c

 

Q4. Answer c

 

Q5. Answer a

 

Q6. Answer a

 

Q7. Answer b

 

Q8. Answer d

 

Q9. Answer a

 

Q10. Answer a

 

Q11. Answer a

 

Q12. Answer a

 

Q13. Answer b

 

Q14. Answer d

 

Q15. Answer c

 

Q16. Answer b

 

Q17. Answer b

 

Q18. Answer c

 

Q19. Answer d

 

Q20. Answer c