Question

In a filtration plant water is filtered using layers of.

• A. Sand.
• B. Oil.
• C. Sand and clay.
• D. Sand, fine gravel and medium gravel.

Answer 1

The correct option is D

Sand, fine gravel and medium gravel.

The correct option is D.

Explanation for the correct option:

1. Sand filters are employed as a phase in the water treatment process.
2. Discharged or wastewater enters a grit and sand removal tank, where the pace of the wastewater is reduced to allow sand, grit, and pebbles to settle.

Explanation for the incorrect options:

Option A:

Only sand is not removed other things are also removed with it.

Option B:

1. A belt oil skimmer is one of the simplest techniques to extract hydrocarbons from water.
2. It is a simple and low-maintenance gadget for extracting oil from water or coolant.
3. However, it can only filter particular chemicals.

Option C:

1. A sediment filter cartridge removes suspended particles from water such as sand, silt, loose scale, clay, or organic material.
2. It cannot remove small particles from water.

Final answer: In a filtration plant water is filtered using layers of sand, fine gravel and medium gravel.