Question

Aeration of water is done to remove ________

(a) odour

(b) colour

(c) hardness

(d) turbidity

This question was posed to me during an interview.

My question is based upon Water Supply, Electrical and Road Work in chapter Rules and Methods of Measurement of Civil Engineering Drawing

Answer 1

Correct choice is (a) odour

Easiest explanation: Aeration of liquids (usually water) is achieved by:

-passing the liquid through air by means of fountains, cascades, paddle-wheels or cones.

-passing air through the liquid by means of the Venturi tube, aeration turbines or compressed air which can be combined with diffuser(s) air stone(s), as well as fine bubble diffusers, coarse bubble diffusers or linear aeration tubing. Ceramics are suitable for this purpose, often involving dispersion of fine air or gas bubbles through the porous ceramic into a liquid. The smaller the bubbles, the more gas is exposed to the liquid increasing the gas transfer efficiency. Diffusers can also be designed into the system to cause turbulence or mixing if desired.