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Q4//A- A triple-effect backward-feed evaporator is fed with 5kg/s of a liquor containing 15 per cent solids. The concentration in the first effect is 60 per cent solids, and the last effect operates at 13.5kN/m2, If the overall heat transfer coefficients in the three effects are 2.3,2.0, and 1.6 kW/m2K, respectively, and the steam is fed at 388K to the first effect, determine the temperature distribution, the heat economy and the area of heating surface required in each effect? The calandrias are identical. The feed temperature is 294K and the specific heat capacity ot all liquors is 4.18kJ/kgK