A tripple effect evaporator with backward feed is evaporating aqueous solution with negligible boiling-point rise containing 10 wt % solids to 50% solids. Fresh saturated steam at 1.02 atm 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 10cmHgAAt given pressure, the boiling point of the solution in the third effect is 51C. The feed rate is 25000kg/h and the temperature 21C. The liquid heat capacity is 4.18kJ/kg C for all concentrations. The heat transfer coefficents are U1=2250,2=1750 and U3=1375kcal/mhC. Calculate the surface area of each effect, the steam rate, distribution of temperatures in each effect and steam economy of system. A tripple effect evaporator with backward feed is evaporating aqueous solution with negligible boiling-point rise containing 10 wt % solids to 50% solids. Fresh saturated steam at 1.02 atm 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 10cmHgAAt given pressure, the boiling point of the solution in the third effect is 51C. The feed rate is 25000kg/h and the temperature 21C. The liquid heat capacity is 4.18kJ/kg C for all concentrations. The heat transfer coefficents are U1=2250,2=1750 and U3=1375kcal/mhC. Calculate the surface area of each effect, the steam rate, distribution of temperatures in each effect and steam economy of system