Rational Mode Parameters of Power Units Operating in Modern Energy Market Conditions

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DOI https://doi.org/10.15407/pmach2024.01.035
Journal Journal of Mechanical Engineering – Problemy Mashynobuduvannia
Publisher Anatolii Pidhornyi Institute for Mechanical Engineering Problems
of National Academy of Science of Ukraine
ISSN  2709-2984 (Print), 2709-2992 (Online)
Issue Vol. 27, no. 1, 2024 (March)
Pages 35-45
Cited by J. of Mech. Eng., 2024, vol. 27, no. 1, pp. 35-45

 

Author

Anatolii O. Tarelin, Anatolii Pidhornyi Institute of Mechanical Engineering Problems of NAS of Ukraine (2/10, Pozharskyi str., Kharkiv, 61046, Ukraine), e-mail: tarelin@ipmach.kharkov.ua, ORCID: 0000-0001-7160-5726

 

Abstract

The paper analyzes the operation of condensing and heating turbines in modern energy market conditions with an assessment of the impact of operating parameters of live and secondary steam on economic indicators. It has been shown that when operating at variable loads, the most effective in terms of high-pressure turbines is a rational reduction in the initial pressure ps (sliding pressure), which leads to an increase in thermal efficiency by 1-1.5%. The experimental results of a study of the vacuum effect in the condenser on fuel consumption are presented in the paper as well. Using a specific example of the K-320-26.5 turbine unit, the need for a rational choice of cooling water flow in winter season to ensure optimal vacuum is shown. The issue of choosing a rational steam reheat temperature tr is examined in more detail. It has been established that one of the main reasons for the decrease in the efficiency of turbine units when operating in variable modes is the irrational use of the reheat temperature and the heat of phase transition in the flow part of the low pressure cylinder. The physical explanation of these processes in the turbine as tr decreases is given in detail. It has been shown that, as a result of analyzing the operation of turbine units of various capacities, a rational choice of reheat temperature (reducing tr by 10-20 °C) increases thermal efficiency by 1-2 %, and turbine efficiency – by 0.4-1.0 %. It is recommended to consider the pressure of the hot steam of the high pressure cylinder (рs), the pressure in the condenser (рc=f(tcirc.water)), as well as the reheating temperature tr, which altogether leads to a reduction in heat consumption by 2.5-3.5 % as rational parameters of steam when operating in variable modes. In order to increase the economic efficiency of the operation of turbine units of TPPs and CPPs at reduced loads, it is recommended to revise the regulatory documentation on the current amendments for changes in the reheat temperature. It is stated that with strict adherence to the recommendations discussed above, fuel savings at TTPs and CHPs in Ukraine can amount to 250–300 thousand tons of coal per year.

 

Keywords: steam turbine, variable loads, mode parameters, fuel consumption, efficiency.

 

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References

  1. Tarelin, A. A. & Sklyarov, V. P. (2007). Razrabotka meropriyatiy po povysheniyu effektivnosti chasti nizkogo davleniya turbiny K-300-240 pri rabote v usloviyakh energorynka [Development of measures to increase the efficiency of the low pressure part of the K-300-240 turbine when operating in the energy market]. Nauka i innovatsii – Science and Innovation, vol. 3, no. 3, pp. 30–35 (in Russian).
  2. Tarelin, A. A., Sklyarov, V. P., Voronovskiy, G. K., Shvedova, T. I., Medvedovskiy, A. V., Kozlokov, A. Yu. Vliyaniye temperatury promperegreva na moshchnost turboagregata T-250/300-240 [Influence of reheat temperature on the power of the T-250/300-240 turbine unit]. Problemy mashinostroyeniya – Journal of Mechanical Engineering – Problemy Mashynobuduvannia, vol. 10, no. 2, pp. 5–8 (in Russian).
  3. Tarelin, A. A., Sklyarov, V. P., Maystrenko, A. Yu., & Kosyachkov, A. V. (2009). Povysheniye ekonomichnosti parovykh turboustanovok pri rabote na neraschetnykh rezhimakh [Increasing the efficiency of steam turbine units when operating in off-design modes]. Vostochno-yevropeyskiy zhurnal peredovykh tekhnologiy – Eastern-European Journal of Enterprise Technologies, no. 2/7 (38), pp. 4–8 (in Russian).
  4. Tarelin, A. O. (2017). Influence of the reheat temperature on the efficiency of the wet-steam turbines of thermal power plants that operate under variable conditions. Thermal Engineering, vol. 64, iss. 4, pp. 295–300. https://doi.org/10.1134/S0040601517030077.
  5. Ivanov, V. A. (1986). Rezhimy moshchnykh paroturbinnykh ustanovok [Modes of powerful steam turbine plants]. Leningrad: Energoatomizdat, 247 p. (in Russian).
  6. Zhao, T., Wan, J., & Liu, J. (2016). Sliding pressure optimization method for steam turbine with main steam flow rate as independent variable. International Journal of Simulation: Systems, Science & Technology, vol. 17 (29), pp. 11.1–11.8. https://doi.org/10.5013/IJSSST.a.17.29.11.
  7. Anozie, A. N. (2011). The search for optimum condenser cooling water flow rate in a thermal power plant. Applied Thermal Engineering, vol. 31 (17–18), pp. 4083–4090. http://doi.org/10.1016/j.applthermaleng.2011.08.014.
  8. Kirillov, I. I. & Yablonik, R. M. (1968). Osnovy teorii vlazhnoparovykh turbin [Fundamentals of the theory of wet steam turbines]. Leningrad: Mashinostroyeniye, 264 p. (in Russian).
  9. Daskal, Yu. I. (1983). Osazhdeniye melkodispersnoy vlagi v turbinnykh reshetkakh [Precipitation of finely dispersed moisture in turbine grids]. Izvestiya vysshikh uchebnykh zavedeniy, Energetika – Energetika. Proceedings of CIS higher education institutions and power engineering associations, no. 12, pp. 81–83 (in Russian).
  10. Shubenko, O. L. & Tarelin, A. O. (2023). Simulation of the erosion-corrosion destruction process of steam turbine low-pressure cylinder blades. Journal of Mechanical Engineering – Problemy Mashynobuduvannia, vol. 26, no. 1, pp. 29–38. https://doi.org/10.15407/pmach2023.01.029.
  11. Tarelin, A. A. & Sklyarov, V. P. (2012). Parovyye turbiny: elektrofizicheskiye yavleniya i neravnovesnyye protsessy [Steam turbines: electrophysical phenomena and nonequilibrium processes]. St. Petersburg: Energotekh, 292 p. (in Russian).

 

Received 21 November 2023

Published 30 March 2024