Question

An oil stream flowing at a rate of 60 m3 /h (?oil = 952.9 kg/m3 ), at temperature of 10°C is to be heated to 175°C+/-0.5°C in a heat exchanger using high pressure saturated steam. (a) With the aid of the steam tables appended to this paper determine the minimum pressure required of a saturated steam stream to achieve this result? [5%] (b) If the actual temperature of the condensing steam is to be 15°C?0.5°C above the minimum what is the operating pressure of the steam supply? [5%] (c) If the specific heat capacity of the oil is given by the following relationship,Cp=1.8+2.5x10^-3T+3x10^-6T^2 kJ/kg T is in degrees Celsius determine the heat requirements to raise the temperature of the oil. [30%] (d) If the exiting steam from the heat exchanger at the operating pressure of (b) above is made up of 25% steam and the balance is liquid water, determine the steam mass and volumetric flow rates to the heat exchanger. [40%] (e) If the exchanger was designed to bring about complete condensation of the steam how much steam would now be required?

Answer 1