A. X/4
B. X/2
C. X
D. 2X
Related Mcqs:
- For satisfactory working of a sludge digestion unit, the pH range of digested sludge should be maintained as___________________?
A. 4.5 to 6.0
B. 6.5 to 8.0
C. 8.5 to 10.0
D. 10.5 to 12.0 - For normal sludge, the value of sludge index for Indian conditions is________________?
A. 0 to 50
B. 50 to 150
C. 150 to 350
D. 350 to 500 - The gas from sludge digestion tank is mainly composed of __________________?
A. nitrogen
B. carbon dioxide
C. hydrogen sulphide
D. methane - Sludge volume index is defined as the ratio of_______________?
A. percentage of sludge by volume to percentage of suspended solids by weight
B. percentage of sludge by volume to percentage of total solids by weight
C. percentage of suspended solids by weight to percentage of sludge by volume
D. percentage of total solids by weight to percentage of sludge by volume - The slope of sewer shall be__________________?
A. given in the direction of natural slope of ground
B. given in the direction opposite to natural slope of ground
C. zero
D. steeper than 1 in 20 - If the time of concentration is 9 minutes, then the intensity of rainfall according to British Ministry of Health formula will be__________________?
A. 4 mm/hr
B. lOmm/hr
C. 20 mm/hr
D. 40 mm/hr - In chlorination, with the rise in temperature of water, death rate of bacteria____________?
A. increases
B. decreases
C. remains unaffected
D. none of the above - Which of the following unit works in anaerobic conditions ?
A. sludge digestion tank
B. sedimentation tank
C. activated sludge treatment
D. trickling filters - The main disadvantage of cement concrete sewers is________________?
A. less strength
B. difficulty in construction
C. difficulty in transportation due to heavy weight
D. less life - For a given discharge, the efficiency of sedimentation tank can be increased by______________?
A. increasing the depth of tank
B. decreasing the depth of tank
C. increasing the surface area of tank
D. decreasing the surface area of tank
