(a) What are the sources of sewage or waste water?
(b) Explain the methods which involve in the conventional waste water treatment.

Explanation

(a) The sources of sewage or waste water involves:
(i) Domestic purpose or house hold activities
(ii)Dye and textile industries
(iii) Leather industries
(iv) Sugar and breweries industries
(v) Paper and pulp industries
(b) The conventional waste water treatment methods involve the following step:
(i) Pre-screening:
Waste water generated from domestic and industrial activities is screened to remove soil and solid particulates
(ii) Aeration: Screened waste water is pumped to an aeration tank. Here the microbial contaminants are removed by the biological degradation, that occurs, in the presence of air.
Sedimentation process:
In this process, the solid particles in suspension form are allowed to settle. The particles that settle out from the suspension is known as sludge.
Sludge removal:
The sludge generated by the degradation process is transferred periodically from the tank for safe disposal.
Disinfection:
Chlorination and ultraviolet (UV) radiation of treated water is required to remove any microorganism contamination.
Water recycling:
The water will then be supplied for domestic or industrial purposes.