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
Related Mcqs:
- The grit chambers of sewage treatment plants, are generally cleaned after__________________?
A. 2 days
B. 7 days
C. 12 days
D. 14 days - 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 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 - The spacing of bars for perforations in coarse screens used for the treatment of sewage, is ____________________?
A. 20 mm
B. 30 mm
C. 40 mm
D. 50 mm - The bottom of the sewage inlet chamber of septic tanks, is provided an outward slope_________________?
A. 1 in 5
B. 1 in 10
C. 1 in 15
D. 1 in 20 - A cylindrical ejector having its height 2 m fills after every 10 minutes with a peak sewage discharge of 0.0157 cumec. The diameter of the ejector chamber, is_____________________?
A. 2.30 m
B. 2.40 m
C. 2.45 m
D. 2.50 m - 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 - If q is the average sewage flow from a city of population P, the maximum sewage flow______________?
A. Q = [(4 + )/(18 + )] q
B. Q = [(18 + P)/(4 + )] q
C. Q = [(18 + )/(4 + )] q
D. Q = [(5 + )/((15 + )] q
