Filtration

Question 1

How does the uniformity of the media in a gravity filter affect the head loss?

Answer 1

The more uniform the media, the slower the head loss build up

Question 2

What gives a good indicator when backwashing is required

Answer 2

Measurement of head loss in a filter

Question 3

Problems from improper backwashing (4)

Answer 3

1. Mudballs
2. Surface cracking
3. Media boils
4. Air binding

Question 4

Greensand media for iron and manganese removal

Answer 4

1. Regenerated by adding potassium permanganate until pink

Question 5

Schmutzdecke is

Answer 5

A dense layer of microorganisms developed on surface. They feed on and break down organic material that get trapped on mat

Question 6

Diatomaceous earth filter is

Answer 6

Composed of siliceous skeletons of microscopic plants called diatoms

Question 7

(4) filtration types

Answer 7

1. Gravity
2. Pressure
3. Diatomaceous
4. Slow sand

Question 8

Dual and multimedia filter allow

Answer 8

More time between backwashing and can handle higher flow rates

Question 9

(3)Slow sand filtration

Answer 9

1. Straining
2. Absorption
3. Biological action