Question

Read the following statements and find out the correct statement.

• A. In domestic sewage, faecal matter, bacteria, cloth and paper fibres are included in dissolved materials.
• B. In wastewater (domestic sewage), sand, silt and clay are included in suspended solids.
• C. In domestic sewage, nutrients (like nitrates, phosphates, ammonia, sodium and calcium) are included in colloidal materials
• D. ll of the above

Answer 1

The correct option is B In wastewater (domestic sewage), sand, silt and clay are included in suspended solids.

Statement A
Domestic sewage is the waste originating from the households like kitchen, toilet, laundry, domestic work.
About $0.1\%$ of impurities are present in the form of suspended solids (like, sand silt and clay), colloids, and dissolved material in domestic sewage.

Statement B
Colloidal materials present in domestic sewage are faecal matter, bacteria, cloth and paper fibres, etc.

Statement C
Dissolved nutrients present in domestic sewage are nitrate ammonia, phosphate, sodium, etc.