Environmental Engineering

A. 500 to 750 litres/hour/ m2
B. 1000 to 1250 litres/hour/ m2
C. 1250 to 1500 litres/hour/m2
D. 1500 to 2000 litres/hour/m2

A. depth of tank
B. surface area of tank
C. both depth and surface area of tank
D. none of the above

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

A. 1 to 2 minutes
B. 30 to 45 minutes
C. 2 to 6 hours
D. 2 to 6 days

A. sulphuric acid
B. copper sulphate
C. lime
D. sodium permanganate

A. 50 to 60
B. 100 to 150
C. 500 to 600
D. 1400 to 1500

1) slower filtration rate
2) higher filtration rate
3) lesser efficiency in removal of bacteria
4) higher efficiency in removal of bacteria
The correct answer is?
A. (1) and (2)
B. (2) and (3)
C. (1) and (4)
D. (2) and (4)

A. excessive negative head
B. mud ball formation
C. higher turbidity in the effluent
D. low temperature

1) scrag and removal in filters slow sand
2) back washing in slow sand filters
3) scrag and removal in filters rapid sand
4) back washing in rapid sand filters
The correct answer is
A. (1) and (2)
B. (2) and (3)
C. (1) and (4)
D. (2) and (4)