1. Shell and Tube Heat Exchanger October 7, 2003 Cycle 2 Group 1A Frank Fadenholz Jennifer Fadenholz Christian Woods Angel Taylor

2. Outline Objectives Objectives Background Background Experimental Strategy Experimental Strategy Results Results Error Analysis Error Analysis Conclusions Conclusions Recommendations Recommendations References References

3. Objectives and Background

4. Objectives Operate shell and tube heat exchanger varying steam flow Operate shell and tube heat exchanger varying steam flow Determine the outside overall heat transfer coefficient (U o ) Determine the outside overall heat transfer coefficient (U o ) Determine shellside heat transfer (Q SS ) Determine shellside heat transfer (Q SS ) Determine tubeside heat transfer (Q TS ) Determine tubeside heat transfer (Q TS )

5. Heat Exchanger Background Exchange heat between fluids Exchange heat between fluids Latent heat and sensible heat transfer Latent heat and sensible heat transfer Common to chemical process industry Common to chemical process industry Types of heat exchangers Types of heat exchangers –Air Cooled –Double Pipe –Spiral Plate and Tube –Shell and Tube

6. Heat Exchanger Background Shell and Tube Heat Exchangers Account for 60% of heat exchangers in use today Account for 60% of heat exchangers in use today Can handle large flows, low temperatures and pressures, high temperatures and pressures Can handle large flows, low temperatures and pressures, high temperatures and pressures Our shell and tube heat exchanger Our shell and tube heat exchanger –Basco Type 500 U-tube Water Heater –1 Shell Pass –16 Tubes

7. Experimental Strategy

8. Should make Labels Larger

9. Experimental Strategy 5 Runs Total 5 Runs Total Varied Steam Valve (TV-04) Position Varied Steam Valve (TV-04) Position –105% open –75% open –65% open –60% open –52% open Cooling water flow rate constant Cooling water flow rate constant

10. Experimental Strategy Measured Variables Measured Variables –Condensate flow –Condensate temperature –Cooling water flow –Cooling water inlet temperature –Cooling water outlet temperature

11. Heat Exchanger Calculations Heat transfer rate Heat transfer rate  Q TS = mCp  T  Q SS = m  H + mCp  T Overall heat transfer coefficient Overall heat transfer coefficient  U o = Q SS /(A o *  T LM )  Log mean temperature  T LM = ((T hi -T co ) – (T ho – T ci )) / ln[(T hi – T co ) – (T ho – T ci )]

12. Simplified Process Flow Diagram T hi T ho T ci T co Q out, TS Q in, TS Q in, SS Q out, SS

13. Results

14. Experimental Results Steam Valve % Open Heat Transfer Rate (Q TS ) (btu/hr) Heat Transfer Rate (Q SS ) (btu/hr) Overall Heat Transfer Coefficient (U o ) (btu/lb*F*hr) 105%276489275350211 75%250275254588201 65%183357181872148 60%134200133777112 52%982899375778

15. Shellside vs. Tubeside Heat Transfer

16. Steam vs. Heat Transfer Rate (Q TS, Q SS )

17. Steam vs. Overall Heat Transfer Coefficient

18. Error Analysis

19. Propagation of Error Determine the accuracy of measured variables Determine the accuracy of measured variables Apply the propagation of error equation to each function Apply the propagation of error equation to each function

20. Variable Measurement Accuracy Flow rate of the steam +/- 5 lb/hr Flow rate of the steam +/- 5 lb/hr Flow rate of the cooling water +/- 50 lb/hr Flow rate of the cooling water +/- 50 lb/hr Temperature readings +/- 2 °F Temperature readings +/- 2 °F Largest sources of error Largest sources of error –Mass flow rate of the steam –Mass flow rate of the cooling water

21. Calculated Error Values ∆Q TS ≈ +/- 1,000 btu/hr ∆Q TS ≈ +/- 1,000 btu/hr ∆Q SS ≈ +/- 50,000 btu/hr ∆Q SS ≈ +/- 50,000 btu/hr ∆U o ≈ +/- 4 btu/lb °F hr ∆U o ≈ +/- 4 btu/lb °F hr ∆U i ≈ +/- 4 to +/- 1.6 btu/lb °F hr ∆U i ≈ +/- 4 to +/- 1.6 btu/lb °F hr

22. Propagation of Error Heat Transfer

23. Propagation of Error Heat Transfer Coefficient

24. Conclusions and Recommendations

25. Conclusions Q TS, Q SS, U o all increase as the steam flow rate increases Q TS, Q SS, U o all increase as the steam flow rate increases Q TS, Q SS, U o all have a linear relationship with the mass flow rate of the steam Q TS, Q SS, U o all have a linear relationship with the mass flow rate of the steam Heat transfer rate of the tube side is equal to the heat transfer rate of the shell side Heat transfer rate of the tube side is equal to the heat transfer rate of the shell side

26. Recommendations Operation Recommendation Operation Recommendation –Operate the shell and tube heat exchanger at approximately 75% for sufficient heat transfer and economic efficiency Experiment Recommendations Experiment Recommendations –Monitor pressure gauge (PG-07) at low steam rates to prevent a vacuum

27. References API Heat Transfer. Shell and Tube Heat Exchanger Picture API Heat Transfer. Shell and Tube Heat Exchanger Picture www.apiheattransfer.com/en/Products/HeatExchangers/ShellAndTu be/ Georgia Tech. Propagation of Error. www.swiki.che.gatech.edu/CHE4200. August 2002. Georgia Tech. Propagation of Error. www.swiki.che.gatech.edu/CHE4200. August 2002. Geankoplis, Christie J. Transport Processes and Unit Operations, 3rd ed. Englewood Cliffs, NJ. Prentice-Hall Publishing, Inc. 1993. Geankoplis, Christie J. Transport Processes and Unit Operations, 3rd ed. Englewood Cliffs, NJ. Prentice-Hall Publishing, Inc. 1993. Heald, C. C. Cameron Hydraulic Data. Liberty Corner, NJ. Ingersoll- Dresser Pump Co. 1998. Heald, C. C. Cameron Hydraulic Data. Liberty Corner, NJ. Ingersoll- Dresser Pump Co. 1998. Peters, Timmerhaus, West. Plant Design and Economics for Chemical Engineers, 5th ed. New York, NY. McGaw-Hill Co. Inc., 2003. Peters, Timmerhaus, West. Plant Design and Economics for Chemical Engineers, 5th ed. New York, NY. McGaw-Hill Co. Inc., 2003.