Question

The number of stages involved in the desalination using a multistage flash evaporator is _________________

(a) 20

(b) 38

(c) 49

(d) 69

I have been asked this question during an internship interview.

Question is from Desalination topic in section Miscellaneous Treatment Methods of Environmental Engineering

Answer 1

Correct answer is (d) 69

To explain I would say: Multistage flash evaporator uses 69 stages in the desalination process. The vapors released during flash each stage condenses to heat the incoming sea water and gives fresh water.