A. 2 days
B. 7 days
C. 12 days
D. 14 days
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 - 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 recommended detention period for grit chambers is_______________?
A. 1 minute
B. 2 minutes
C. 3 minutes
D. 5 minutes - The small sewers are cleaned by____________________?
A. Flushing
B. Cane rodding
C. Wooden pills
D. None of these - If a 2% solution of sewage sample is incubated for 5 days at 20°C and the dissolved oxygen depletion was found to be 8 mg/l. The BOD of the sewage is_________________?
A. 100 mg/l
B. 200 mg/l
C. 300 mg/l
D. 400 mg/l - 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 - A five day B.O.D. at 15°C of the sewage of a town is 100 kg/day. If the 5 day B.O.D. per head at 15°C for standard sewage is 0.1 kg/day, the population equivalent is____________________?
A. 100
B. 1000
C. 5000
D. 10000 - If the depletion of oxygen is found to be 2.5 mg/litre after incubating 2.5 ml of sewage diluted to 250 ml for 5 days at 20°C, B.O.D. of the sewage is_________________?
A. 50 mg/l
B. 100 mg/l
C. 150 mg/l
D. 250 mg/l - 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
