A saline solution is concentrated from 5% to 40% by weight. For this, 15000 kg/h of the diluted solution are fed to a double-effect evaporator that operates in countercurrent. The steam used in the first effect is saturated steam at a pressure of 232.1 kPa. The second effect evaporation chamber operates at a pressure of 19.94 kPa. The overall heat transfer coefficient for effects 1 and 2 is 1860 and 1280 W/m2 C, respectively. It is known that the specific heat of the salt solution is a function of its concentration according to equation 1: Cp = 4.18 * 3.34 * x_i = (KJ/Kg) where x_i is the mass fraction of the solution. If the power enters the system at 25 C. Calculate: a) Steam flow necessary for the process and its economy .

b) Heat transfer area for each effect Assume that the outgoing vapor flows in both effects are equal. That the heat transfer area is the same for both effects. The rate of heat transfer is the same for both effects.

Use international measurement system.

Make a diagram for the evaporators