1. Heat Exchangers Types of heat exchangers Constraints on temperature differences Materials Costing

3. Shell-and-Tube Heat Exchanger

4. Double-Pipe Exchanger

5. Spiral Heat Exchanger

6. Plate Heat Exchanger

7. Shell-and-Tube Heat Exchanger

8. Shell and Tube Exchanger Terms Fanaritis, J.P., Bevevino, J.W. "Designing shell and tube heat exchangers". Chemical Engineering, 83(13), 62-71, 1976. Bayonet type - floating inner tubes and floating heads for large temperature differences

9. Heat Exchanger Selection Brown, 1985

11. Air-Cooled Exchangers Design for worst case - summer air temperatures of 30-35  C Typical approach temperature is 50 C  Maximum process fluid temperature ca. 260  C Typical inlet process fluid temperature < 150  C Ganapathy, 1978; Ulrich, 1982

12. Air-Cooled or Fin-Fan Exchanger

13. Air Cooling vs Water Cooling Air cooling (+) corrosive water pollution water consumption maintenance Water cooling (tower) (+) temperature control space freeze up noise achievable T power

14. Heat Integration Temperature profiles –crossovers –phase changes –correct delta T Keeping heat in the process saves utility costs –integrated processes save money –heat exchangers (always) leak

15. T cross

17. Design Equation Q=amount of heat transferred (from process design) A=heat exchanger area MTD=mean temperature difference=f  T LM f=correction factor for exchanger geometry f=1 for true counter-current; f<1 when cross-flow