Storage and screens

Question 1

Long storage results in reduction in turbidity and bacterial content particularly pathogenic

Answer 1

90 percent of pathogenic bacterial die in 5-7 days storage

Question 2

Is open storage deirable

Answer 2

No, it is not desirable because of algal growth which create odors

Question 3

For what screens are used

Answer 3

Screens are used to remove large objects

Question 4

Where are screens placed

Answer 4

Screens are placed at water inlets before pumping stations

Question 5

Screens are classified by mode of operation into

Answer 5

Fixed and mechanical screens

Question 6

Screens are classified by size opening into

Answer 6

fine, medium, and coarse screens

Question 7

Approach velocity of water toward screens should not exceed 0.9-1 m/s

Answer 7

Because of the approach velocity is more, i will punch objects through the screen(like papers and other)

Question 8

Also the approach velocity of water must not be below 0.3-0.6 m/s

Answer 8

because if the water speed is less the particles will settle in the channel