Question

A wastewater stream at 25C is to be treated using a reverse osmosis syste. The wastewater has a flowrate of 50 gal/min and a concentration of 5000 mg/L of sodium chloride. A reverse osmosis vendor has recommended a membrane with the following characteristics:

permeability coefficent = 1.9X10^-6gmol/cm²*s*atm=K

area for a bundle=300ft²

optimal pressure differential across the membrane=500psi=Delta P

Determine:

a) Osmotic pressure of the solution

b) the water flow through the membrane

c) the number of units required

Answer 1