Question

The period of cleaning of a slow sand filter is ______ than rapid sand filter.

(a) Smaller

(b) Larger

(c) Slightly smaller

(d) Slightly larger

The question was posed to me in an international level competition.

My question comes from Comparison Between Slow and Rapid Sand Filter topic in portion Filtration of Environmental Engineering

Answer 1

Right option is (b) Larger

Explanation: The period of cleaning of a slow sand filter is 1-2 months and that of the rapid sand filter is 2-3 days.