The detention time of a circular tank of diameter d and water depth H, for receiving the sewage Q per hour, is________________?

Related Mcqs:

1. The dimensions of a rectangular settling tank are: length 24 m, width 6 m and depth 3 m. If 2 hour detention period for tanks is recommended, the rate of flow of sewage per hour, is_____________________?

   A. 204 cu.m
   B. 208 cu.m
   C. 212 cu.m
   D. 216 cu.m

2. The width of a settling tank with 2 hour detention period for treating sewage 378 cu m per hour, is __________________?

   A. 5 m
   B. 5.5 m
   C. 6.5 m
   D. 7 m

3. The settling velocity of the particles larger than 0.06 mm in a settling tank of depth 2.4 is 0.33 m per sec. The detention period recommended for the tank, is____________________?

   A. 30 minutes
   B. 1 hour
   C. 1 hour and 30 minutes
   D. 2 hours

4. The sewage discharge in a detritus tank of a treatment plant is 576 litres/sec with flow velocity of 0.2 m/sec. If the ratio of width to depth is 2, the depth is____________________?

   A. 100 cm
   B. 110 cm
   C. 120 cm
   D. 150 cm

5. The density of population over 40 hectares is 250/hectare. If water supply demand per day is 200 litres and sewage discharge is 80% of water supply, the sewage flow in sewers of separate system, is_____________________?

   A. 0.05552 cumec
   B. 0.05554 cumec
   C. 0.05556 cumec
   D. 0.0556 cumec

6. The ratio of maximum sewage flow to average sewage flow for mains up to 1 m in diameter, is___________________?

   A. 1.5
   B. 2.0
   C. 3.0
   D. 4.0

7. For trunk sewers more than 1.25 m in diameter, the ratio of the maximum daily sewage flow to the average daily sewage flow is assumed________________?

   A. 1.5
   B. 2.0
   C. 2.5
   D. 3.0

8. For sewer mains of 0.5 to 1 m diameter, the ratio of maximum daily sewage flow to the average daily sewage flow is assumed__________________?

   A. 1.5
   B. 2.0
   C. 2.5
   D. 3.0

9. In circular sewers if depth of flow is 0.2 times the full depth, the nominal gradient,______________?

   A. Is only provided
   B. Is doubled
   C. Is trebled
   D. Is not enough

10. If is the diameter of upper circular portion, the overall depth of a standard egg shaped section, is___________________?

    A. D
    B. 1.25 D
    C. 1.5 D
    D. 1.75 D