A. 1 minute
B. 2 minutes
C. 3 minutes
D. 5 minutes
Related Mcqs:
- If the grit in grit chambers is 4.5 million litres per day, its cleaning is done____________________?
A. Manually
B. Mechanically
C. Hydraulically
D. Electrically - The grit and silt of the grit chambers, may not be used for_________________?
A. Raising low lying areas by dumping
B. Concreting
C. Both A. and B.
D. Neither A. nor B - For a grit chamber, if the recommended velocity of flow is 0.2 m/sec and detention period is 2 minutes, the length of the tank, is__________________?
A. 16 m
B. 20 m
C. 24 m
D. 30 m - The grit chambers of sewage treatment plants, are generally cleaned after__________________?
A. 2 days
B. 7 days
C. 12 days
D. 14 days - 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 - 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 - The detention period for plain sedimentation water tanks, is usually____________________?
A. 4 to 8 hours
B. 8 to 16 hours
C. 16 to 24 hours
D. 24 to 36 hours - 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 - In a grit chamber of a sewage treatment plant ____________________?
A. Flow velocity 0.15 m to 0.3 m/sec is kept
B. Depth of 0.9 m to 1.20 m is kept
C. One minute of detention period is kept
D. All the above - The detention time of a circular tank of diameter d and water depth H, for receiving the sewage Q per hour, is________________?
A. d² (0.011d + 0.785H)/Q
B. d (0.022d + 0.085H)/Q
C. d (0.785d + 0.011H)/Q
D. d (0.285d + 0.011H)/Q
