THERMODYNAMIC COMPARISION OF R744/R600A AND R744/R600 USED IN MID-HIGH TEMPERATURE HEAT PUMP SYSTEM

Abstract

The mid-high temperature heat pump provides hot water at a relatively high temperature using some industrial waste heat as its source. Now, the main refrigerants in this application are CFC114, HCFC123, and HCFC142b, etc., which are scheduled to be phased out due to their high ozone depletion potential and global warmth potential. Some studies have been conducted to find an eco-friendly alternative. In this paper, the natural non-azeotropic mixtures R744/R600a and R744/R600 are analyzed as alternatives. The performance of the heat pump system using new mixture is discussed and compared with those with CFC114, HCFC123, and HCFC142b. Under the given operating conditions, the maximum heating COP should occur at the mass fractions of 18/82 for R744/R600a and 10/90 for R744/R600. Both of their COP are higher than those with the refrigerants of CFC114, HCFC123, and HCFC142b. The COP and volumetric heating capacity of the system with R744/R600a are superior to those with R744/R600.

Keywords

Dates

  • Submission Date2013-10-02
  • Revision Date2014-03-06
  • Acceptance Date2014-07-13
  • Online Date2015-01-04

DOI Reference

10.2298/TSCI1405655F

References

  1. Chua, K. J., et al., Advances in Heat Pump Systems: A review, Applied Energy, 87 (2010), 12, pp. 3611- 3642
  2. Laue, H. J., Regional Report Europe: "Heat Pumps - Status and Trends", International Journal Refrigeration, 25 (2002), 4, pp. 414-420
  3. Li, T. X., et al., High Temperature Hot Water Heat Pump with Non-Azeotropic Refrigerant Mixture HCFC-22/HCFC-141b, Energy Conversion and Management, 43 (2002), 15, pp. 2033-2040
  4. Liu, N. X., et al, Moderately High Temperature Water Source Heat-Pumps Using a Near-Azeotropic Refrigerant Mixture, Applied Energy, 80 (2005), 4, pp. 435-447
  5. Gao, P., Zhao, L., Research on Cycle Working Fluids for Moderate and High Temperature Heat Pump Systems, Heating Ventilating & Air Conditioning, 36 (2006), 1, pp. 24-27
  6. Pan, L. S., et al., Experimental Research on Two Natural Working Fluids of Moderately High Temperature Heat Pump, Acta Energiae Solaris Sinica, 33 (2012), 4, pp. 827-831
  7. Minea, V., Drying Heat Pumps - Part I: System Integration, International Journal of Refrigeration, 36 (2013), 3, pp. 643-658
  8. Sarkar, J., Bhattacharyya, S., Assessment of Blends of CO2 with Butane and Isobutane as Working Fluids for Heat Pump Applications, International Journal of Thermal Sciences. 48 (2009), 7, pp. 1460-1465
  9. Zhang, X. P., et al., Theoretical and Experimental Studies on Optimum Heat Rejection Pressure for a CO2 Heat Pump System, Applied Thermal Engineering, 30 (2010), 16, pp. 2537-2544
  10. Fan, X. W., et al., Research on Performance of Heat Pump Systems Using R744/R600 and R744/R600a Mixtures as Refrigerants (in Chinese), Journal of Refrigeration, 32 (2011), 6, pp. 35-39
  11. Sun, F. T, et al., New Waste Heat District Heating System with Combined Heat and Power Based on Absorption Heat Exchange Cycle in China, Applied Thermal Engineering, 37 (2012), 5, pp. 136-144
  12. Lemmon, E. W., et al., Reference Fluid Thermodynamic and Transport Properties (REFPROP), NIST Standard Reference Database 23, Version 9.0, 2012
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