Machines. Technologies. Materials.
Vol. 19 (2025), Issue 2, pg(s) 49-52

MACHINES

Exergy analysis of several pressure reduction valves during operation in steam power plant

  • 1 Faculty of Engineering, University of Rijeka, Vukovarska 58, 51000 Rijeka, Croatia

Abstract

This paper presents an exergy analysis of six pressure reduction valves which operate in a condensate/feedwater heating system of a 660 MW coal-fired steam power plant. For all observed pressure reduction valves is additionally investigated the ambient temperature change influence of their exergy parameters. Second pressure reduction valve (PRV2) has the highest exergy destruction of all observed valves (equal to 1003.36 kW at the base ambient state). The first five observed pressure reduction valves (from PRV1 to PRV5) have very high exergy efficiencies at the base ambient state, higher than 90%. The last observed valve, PRV6, has an exergy efficiency at the base ambient state notably lower in comparison to other five valves, equal to 64.90% only. The exergy variables of any pressure reduction valve are more and more influenced by the ambient temperature change when the operating parameters of working fluid which flows through the valve (fluid pressure and temperature) are closer to the ambient state.

Keywords

References

  1. Mrzljak, V., Lorencin, I., Anđelić, N., & Car, Z. (2021). Thermodynamic Analysis of a Condensate Heating System from a Marine Steam Propulsion Plant with Steam Reheating. Journal of Marine Science and Application, 20(1), 117-127. (doi:10.1007/s11804-021-00191-5)
  2. Ahmadi, G. R., & Toghraie, D. (2016). Energy and exergy analysis of Montazeri steam power plant in Iran. Renewable and Sustainable Energy Reviews, 56, 454-463. (doi:10.1016/j.rser.2015.11.074)
  3. Kopac, M., & Hilalci, A. (2007). Effect of ambient temperature on the efficiency of the regenerative and reheat Çatalağzı power plant in Turkey. Applied Thermal Engineering, 27(8-9), 1377-1385. (doi:10.1016/j.applthermaleng.2006.10.029)
  4. Mitrović, D., Zivkovic, D., & Laković, M. S. (2010). Energy and exergy analysis of a 348.5 MW steam power plant. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 32(11), 1016-1027. (doi:10.1080/15567030903097012)
  5. Sutton, I. (2017). Plant design and operations. Gulf Professional Publishing
  6. Elčić, Z. (1995). Steam turbines. ABB, Karlovac, National and University Library Zagreb.
  7. Moran, M. J., Shapiro, H. N., Boettner, D. D., & Bailey, M. B. (2010). Fundamentals of engineering thermodynamics. John Wiley & Sons.
  8. Mrzljak, V., Ţarković, B., & Poljak, I. (2017). Energy and exergy analysis of sea water pump for the main condenser cooling in the LNG carrier steam propulsion system. Mathematical Modeling, 1(3), 144-147.
  9. Kostyuk, A., & Frolov, V. (1988). Steam and gas turbines. Mir Publishers.
  10. Leyzerovich, A. S. (2021). Steam turbines for modern fossil-fuel power plants. River Publishers.
  11. Mrzljak, V., Poljak, I., & Ţarković, B. (2018). Exergy analysis of steam pressure reduction valve in marine propulsion plant on conventional LNG carrier. NAŠE MORE: znanstveni časopis za more i pomorstvo, 65(1), 24-31. (doi:10.17818/NM/2018/1.4)
  12. Dincer, I., & Rosen, M. A. (2012). Exergy: energy, environment and sustainable development. Newnes.
  13. Kanoğlu, M., Çengel, Y. A., & Dinçer, İ. (2012). Efficiency evaluation of energy systems. Springer Science & Business Media.
  14. Poljak, I., & Mrzljak, V. (2023). Thermodynamic Analysis and Comparison of Two Marine Steam Propulsion Turbines. NAŠE MORE: znanstveni časopis za more i pomorstvo, 70(2), 0-0. (doi:10.17818/NM/2023/2.2)
  15. Elhelw, M., Al Dahma, K. S., & el Hamid Attia, A. (2019). Utilizing exergy analysis in studying the performance of steam power plant at two different operation mode. Applied Thermal Engineering, 150, 285-293. (doi:10.1016/j.applthermaleng.2019.01.003)
  16. Noroozian, A., Mohammadi, A., Bidi, M., & Ahmadi, M. H. (2017). Energy, exergy and economic analyses of a novel system to recover waste heat and water in steam power plants. Energy conversion and management, 144, 351-360. (doi:10.1016/j.enconman.2017.04.067)
  17. Mrzljak, V., Jelić, M., Poljak, I., & Prpić-Oršić, J. (2023). Analysis and Comparison of Main Steam Turbines from Four Different Thermal Power Plants. Pomorstvo, 37(1), 58-74. (doi:10.31217/p.37.1.6)
  18. Adibhatla, S., & Kaushik, S. C. (2014). Energy and exergy analysis of a super critical thermal power plant at various load conditions under constant and pure sliding pressure operation. Applied thermal engineering, 73(1), 51-65. (doi:10.1016/j.applthermaleng.2014.07.030)
  19. Poljak, I., Mrzljak, V., Senčić, T., & Pastorčić, D. (2024). Isentropic and exergy analyses of marine steam turbine segments at several loads. Scientific Journal of Maritime Research-Pomorstvo, 38(1). (doi:10.31217/p.38.1.8)
  20. Mrzljak, V., Poljak, I., & Mrakovčić, T. (2017). Energy and exergy analysis of the turbo-generators and steam turbine for the main feed water pump drive on LNG carrier. Energy conversion and management, 140, 307-323. (doi:10.1016/j.enconman.2017.03.007)
  21. Tan, H., Shan, S., Nie, Y., & Zhao, Q. (2018). A new boil-off gas re-liquefaction system for LNG carriers based on dual mixed refrigerant cycle. Cryogenics, 92, 84-92. (doi:10.1016/j.cryogenics.2018.04.009)
  22. Baressi Šegota, S., Lorencin, I., Anđelić, N., Mrzljak, V., & Car, Z. (2020). Improvement of marine steam turbine conventional exergy analysis by neural network application. Journal of Marine Science and Engineering, 8(11), 884. (doi:10.3390/jmse8110884)
  23. Erdem, H. H., Akkaya, A. V., Cetin, B., Dagdas, A., Sevilgen, S. H., Sahin, B., ... & Atas, S. (2009). Comparative energetic and exergetic performance analyses for coal-fired thermal power plants in Turkey. International Journal of Thermal Sciences, 48(11), 2179- 2186. (doi:10.1016/j.ijthermalsci.2009.03.007)
  24. Koroglu, T., & Sogut, O. S. (2018). Conventional and advanced exergy analyses of a marine steam power plant. Energy, 163, 392-403. (doi:10.1016/j.energy.2018.08.119)
  25. Mrzljak, V., Anđelić, N., Poljak, I., & Orović, J. (2019). Thermodynamic analysis of marine steam power plant pressure reduction valves. Pomorski zbornik, 56(1), 9-30. (doi:10.18048/2019.56.01)
  26. Fu, P., Wang, N., Wang, L., Morosuk, T., Yang, Y., & Tsatsaronis, G. (2016). Performance degradation diagnosis of thermal power plants: A method based on advanced exergy analysis. Energy Conversion and Management, 130, 219-229. (doi:10.1016/j.enconman.2016.10.054)
  27. Lemmon, E. W., Huber, M. L., & McLinden, M. O. (2010). NIST Standard Reference Database 23, Reference Fluid Thermodynamic and Transport Properties (REFPROP), version 9.0, National Institute of Standards and Technology. R1234yf. fld file dated December, 22, 2010.
  28. Mrzljak, V., Poljak, I., & Medica-Viola, V. (2016). Efficiency and losses analysis of low-pressure feed water heater in steam propulsion system during ship maneuvering period. Pomorstvo, 30(2), 133-140. (doi:10.31217/p.30.2.6)
  29. Mrzljak, V., Poljak, I., Jelić, M., & Prpić-Oršić, J. (2023). Thermodynamic Analysis and Improvement Potential of Helium Closed Cycle Gas Turbine Power Plant at Four Loads. Energies, 16(15), 5589. (doi:10.3390/en16155589)
  30. Anđelić, N., Baressi Šegota, S., Lorencin, I., Poljak, I., Mrzljak, V., & Car, Z. (2021). Use of Genetic Programming for the Estimation of CODLAG Propulsion System Parameters. Journal of Marine Science and Engineering, 9(6), 612. (doi:10.3390/jmse9060612)
  31. Anđelić, N., Lorencin, I., Mrzljak, V., & Car, Z. (2024). On the application of symbolic regression in the energy sector: Estimation of combined cycle power plant electrical power output using genetic programming algorithm. Engineering applications of artificial intelligence, 133, 108213. (doi:10.1016/j.engappai.2024.108213)

Article full text

Download PDF