Question

Identify the correct statement from the following options.

(a) Rapid sand filter has a high initial cost

(b) Coagulation is essential in slow sand filter

(c) Slow sand filter requires skilled supervision

(d) Period of cleaning of Rapid sand filter is 1-2 days

I got this question during an interview for a job.

My question comes from Theory and classification of Filtration topic in section Filtration of Environmental Engineering

Answer 1

Right option is (d) Period of cleaning of Rapid sand filter is 1-2 days

The best explanation: Rapid sand filter is cheap and economical and its period of cleaning is 1-2 days. Neither the coagulation nor the skilled supervision is required in the slow sand filter.