14. Questions for Practice

  1. A triple effect evaporator concentrates a liquid with no appreciable elevation in boiling point. If the temperature of the steam to the first effect is 395 K and the vacuum in the last effect brings down the boiling point to 325 K, what are the approximate boiling points of liquid in first and second effect? Assume the overall heat transfer coefficient as 3.1, 2.3 and 1.1 kW/m\(^2\).K in the first, second and third effects respectively. Assume that all the three evaporators have the same area (\(A_1=A_2=A_3\)), and same heat transfer rate (\(Q_1=Q_2=Q_3\)).

  2. Calculate the steam economy for the data given in the schematic as below:


  3. Calculate the steam economy for the data given in the schematic as below: