A triple-effect evaporator with forward feed is evaporating aqueous solution with negligible boiling-point rise and containing 10 wt % solids to 50% solids. Fresh saturated steam at 1.02atm abs (corresponding to 120C of temperature) is used for heating in the first effect. The pressure in the vapor space of the third effect is 10cmHg. At given pressure, the boiling point of the solution in the third effect is 51C. The feed rate 25000kg/h and the temperature 21C. The liquid heat capacity is 4.18kJ/kgC for all liquid concentrations. The heat-transfer coefficients are U1=2750,U2=1750, and U3=1000 kcal/m2hC. Calculate the surface area of each effect, mass flow rate of the steam, distribution of temperatures in each effect and steam economy of system. QUESTION (Homework) Recalculate Example 2 but use a backward-feed triple-effect evaporator to evaporate aqueous solution with negligible boiling-point rise and containing 10wt% solids to 50% solids. Use the same saturated steam pressure. The pressure in the vapor space of the third effect is same. The properties of feed is same. The liquid heat capacity is 4.18kJ/kgC for all concentrations. The heat-transfer coefficients are U1=2250,U2=1750, and U3=1375kcal/m2hC. Calculate the surface area of each effect, the steam rate, distribution of temperatures in each effect and steam economy of system