Question

Which of the following is the best filter in terms of rate of filtration?

(a) Pressure filter

(b) Rapid sand filter

(c) Dual media filter

(d) Mixed media filter

I had been asked this question in an interview for internship.

My question is taken from Dual Media and Mixed Media Filter topic in portion Filtration of Environmental Engineering

Answer 1

The correct choice is (d) Mixed media filter

Easy explanation: Dual media filter has greater depth of filter media in comparison to rapid sand filter, whereas mixed media filter is an improved version of dual media filter having three materials for filter layers resulting in increased filter run times and water quality.