The chlorine vapor leaving the vaporizer passes through an adiabatic expansion valve in which its pressure drops by 640 mm Hg and its temperature drops to 3°C. It then goes through a heat exchanger in which its temperature is raised to 25°C, and from there it proceeds to the chlorine absorber. Calculate the rate (kJ/h) at which heat must be transferred to the chlorine vapor in the heat exchanger, using the approximate heat capacity given in Problem 12.22.

Problem 12.22.

Liquid chlorine at 22°C is pumped continuously to the chlorine vaporizer. The vaporization process causes the temperature of the chlorine to drop. Take the heat of vaporization of chlorine to be 290 kJ/kg and the heat capacity of chlorine vapor to be 0.48 kJ/(kg∙°C).