[ooiuniscience]

A single-effect evaporator concentrates 5kg/s of a solution from 10% to 50% of solids. Steam is available at 205 kN/meter square (ΔH=2672 kJ/kg) and evaporation take place at 13.5 kN/meter square (ΔH=2694 kJ/kg at T 325 K).
If the overall heat transfer coefficient is 3 kW/(meter square Kelvin), calculate the area of the heating surface required and the amount of steam used if the feed enters the evaporator at 294 K and the condensate leaves the heating space at 325.7 K.

(Given specific heat of 10% solution is 3.76kJ/kgK, specific heat of 50% solution is 4.41 kJ/kgK, and the specific heat of condensate at 352.7 K is 3.18 kJ/kgK).