Question

The separation of solid waste from domestic sewage is known as __________.

• A. slurry
• B. sludge
• C. humus
• D. manure

Answer 1

The correct option is B

sludge

The correct option is B.

Explanation of the correct option:

1. Sludge is human waste (such as faeces) that remains in wastewater after sewage treatment.
2. It is used to make biogas and manure since it is organic waste.
3. A scrapper collects the sludge. It is moved to a separate tank where anaerobic microorganisms break down it.

Explanation of the incorrect option:

Option A:

A slurry is a mixture of denser solids in a liquid, often water.

Option C:

Humus is a dark-coloured organic matter formed when plant and animal remnants in the soil decompose.

Option D:

Manure is the degraded form of dead plants and animals that are utilized in agriculture as an organic fertilizer.

Final answer: The separation of solid waste from domestic sewage is known as sludge.