Question

In which action of filtration, removal of particulate matter takes place?

(a) Mechanical Straining

(b) Sedimentation

(c) Biological mechanism

(d) Electrolytic action

This question was addressed to me during an online interview.

This interesting question is from Theory and classification of Filtration in chapter Filtration of Environmental Engineering

Answer 1

Correct answer is (d) Electrolytic action

For explanation: Filter removes the particulate matter by electrostatic exchange where the charge of the filter medium neutralizes the charge of the floc and permitting it to be removed.