Problem 2 (10 points): The enthalpy of normal liquids changes linearly with temperature. However, the enthalpy...

 

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Problem 2 (10 points): The enthalpy of normal liquids changes linearly with temperature. However, the enthalpy of a high pressure gas can be non-linearly related to the temperature because the Cp becomes very large near the critical point. Consider a countercurrent heat exchanger to cool 100 mol/min of CO2 stream entering at 8.6 MPa and 115C. The outlet is to be 8.6 MPa and 22C. The cooling is to be performed using a countercurrent stream of water that enters at 10C and a constant flow rate of 6 kg/min. The water and gas do not mix but only exchange thermal energy. The pressure of water remains at 0.1 MPa. Assume PR-EOS for CO2 and steam tables for water. (i). Using enthalpy of the outlet CO2 as the reference, tabulate and plot the temperature of CO2 vs its total enthalpy. You must choose a step size between 1 to 5 C to go from 115C to 22C. Problem 2 (10 points): The enthalpy of normal liquids changes linearly with temperature. However, the enthalpy of a high pressure gas can be non-linearly related to the temperature because the Cp becomes very large near the critical point. Consider a countercurrent heat exchanger to cool 100 mol/min of CO2 stream entering at 8.6 MPa and 115C. The outlet is to be 8.6 MPa and 22C. The cooling is to be performed using a countercurrent stream of water that enters at 10C and a constant flow rate of 6 kg/min. The water and gas do not mix but only exchange thermal energy. The pressure of water remains at 0.1 MPa. Assume PR-EOS for CO2 and steam tables for water. (i). Using enthalpy of the outlet CO2 as the reference, tabulate and plot the temperature of CO2 vs its total enthalpy. You must choose a step size between 1 to 5 C to go from 115C to 22C.