A. 0.05 m/sec
B. 0.09 m/sec
C. 1.25 m/sec
D. None of these
Related Mcqs:
- 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 - In detritus tanks______________________?
A. Flow velocity is kept 0.09 m/sec
B. Detention period is kept 3 to 4 minutes
C. Organic and inorganic materials are separated
D. All the above - The normal values of over flow rates for secondary sedimentation tanks, ranges between__________________?
A. 25,000 to 35,000 litres/sqm/day
B. 40,000 to 50,000 litres/sqm/day
C. 50,000 to 60,000 litres/sqm/day
D. 80,000 to 10,000 litres/sqm/day - 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 normal value of over flow rates for plain primary sedimentation tanks, ranges between________________?
A. 25,000 to 35,000 litres/sqm/day
B. 40,000 to 50,000 litres/sqm/day
C. 50,000 to 60,000 litres/sqm/day
D. 80,000 to 100,000 litres/sqm/day - The normal values of over flow rates for sedimentation tanks using coagulant, ranges between__________________?
A. 25,000 to 35,000 litres/sqm/day
B. 40,000 to 50,000 litres/sqm/day
C. 50,000 to 60,000 litres/sqm/day
D. 80,000 to 100,000 litres/sqm/day - For a peak discharge of 0.0157 cumec, with a velocity of 0.9 m/sec, the diameter of the sewer main, is________________?
A. 10 cm
B. 12 cm
C. 15 cm
D. 18 cm - If the diameter of a sewer is 150 mm, the gradient required for generating self cleansing velocity, is________________?
A. 1 in 60
B. 1 in 100
C. 1 in 120
D. None of these - Skimming tanks are__________________?
A. Used to remove the grease and oil
B. Those from which sludge is skimmed out
C. Tanks provided with self- cleansing screens
D. Improved version of grit chambers - Assertion A.: A free board of 0.3 m is provided above the top sewage line in septic tanks. Reason (R): It helps to accommodate the scum in the septic tank_________________?
A. Both A and R is true and R is the correct explanation of A
B. Both A and R is true but R is not a correct explanation of A
C. A is true but R is false
D. A is false but R is true
