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A three-stage evaporator is fed with 1.25kg/s of a liquor which is concentrated from 10 to 40 percent solids. The heat transfer coefficients may be taken as 3.1,2.5, and 1.7kW/m2K respectively. Calculate the required steam flowrate at 170kN/m2 and the temperature distribution in the three effects, if: 1. If the feed is at 294K, and 2. If the feed is at 355K Forward feed is used in each case, and the values of U are the same for the two systems. The boiling-point in the third effect is 325K, and the liquor has no boiling-point rise