Русская версия English version
Home / 2026 issue 1 / Selection of working fluid for organic Rankine cycle using nitric acid production as an example

Selection of working fluid for organic Rankine cycle using nitric acid production as an example

Ye.A. Shelginsky, Yu.V. Yavorovsky, A.Ya. Shelginsky

Vestnik IGEU, 2026 issue 1, pp. 30—39

Download PDF

Abstract in English: 

Background. One of the ways to utilize the heat of secondary energy resources in the industrial sector is to use organic Rankine cycle installations, which use low-boiling organic substances. Organic Rankine cycle is applied both in industry and renewable energy sector. The production of weak nitric acid is carried out using the Ostwald method. There are two main nitric acid production units in Russian Federation. They are AK-72 (AK-72M) and UCL-7 (UCL-7M). Both units were designed in the second half of the ХХ   century in the USSR. They have significant shortcomings due to the emission of low-potential and medium-potential thermal energy into the environment. Therefore, one of the vital tasks is to find ways to increase energy efficiency in nitric acid production, especially taking into account the constant increase in prices for fuel resources and electricity.

Materials and methods. The energy efficiency analysis of the UCL-7 unit has been carried out using heat balance equations and the coefficient of efficient use of thermal energy. It is proposed to utilize the heat of compressed air in the UСL-7 unit for the production of weak nitric acid using the organic Rankine cycle.

Results. The authors have proposed a method to select an applicable suitable low-boiling working fluid with the determination of pressures, temperatures and pinch-point (the minimum temperature difference during heat exchange in heat exchangers of the organic Rankine cycle), corresponding to the maximum useful effective power of the organic Rankine cycle. Thermodynamic parameters (pressure, temperature, thermal and effective efficiency) of the organic Rankine cycle for twelve low-boiling working fluids have been obtained. The working fluid for which the cycle has the highest effective power value has been determined. Working fluids have been selected based on environmental characteristics. Applicable low-boiling working fluids have been identified. The efficiency of the UCL-7 unit has been determined for each working fluid using the organic Rankine cycle.

Conclusion. The proposed methodology based on a thermodynamic analysis of energy efficiency, make it possible to select an applicable low-boiling working fluid from the substances considered when utilizing the heat of compressed air for the organic Rankine cycle during the production of weak nitric acid in the UCL-7 unit according to the proposed thermal scheme.

References in English: 
  1. Alkotami, A. Thermodynamic Performance Analysis and Design of an Organic Rankine Cycle (ORC) Driven by Solar Energy for Power Generation. Sustainability, 2025, vol. 17, issue 13, p. 5742. https:// doi.org/10.3390/su17135742
  2. Chandio, M.W., Kumar, L., Memon, A.G., Awad, M.M. Thermodynamic, economic, and environmental evaluation of internal combustion engine exhaust gas-driven Organic Rankine cycles for power generation and desalination. International Journal of Thermofluids, 2025, vol. 25, p. 101046. https://doi.org/10.1016/j.ijft.2024.101046
  3. Das, M., Reddy, K.S. Modelling and optimization of combined supercritical carbon dioxide Brayton cycle and organic Rankine cycle for electricity and hydrogen production. Applied Energy, 2025, vol. 377, part C, p. 124586. https://doi.org/10.1016/j.apenergy.2024.12458.
  4. Pan, Z., Fu, Y., Chen, H., Song, Y. Thermodynamic analysis of a cascade organic Rankine cycle power generation system driven by hybrid geothermal energy and liquefied natural gas. Front. Energy Res, 2024, vol. 12, p. 1474714. DOI: 10.3389/fenrg.2024.1474714.
  5. Fakharzadeh, M., Tahouni, N., Abbasi, M., Panjeshahi, M.H. Optimization and exergy analysis of a cascade organic Rankine cycle integrated with liquefied natural gas regasification process. International Journal of Refrigeration, 2023, vol. 156, pp. 186–197. https://doi.org/10.1016/j.ijrefrig.2023.10.004.
  6. Bellos, E. A review of organic Rankine cycles with partial evaporation and dual-phase expansion. Sustainable Energy Technologies and Assessments, 2024, vol. 72, p. 104059. https://doi.org/10.1016/j.seta.2024.104059.
  7. Dawo, F., Buhr, J., Schifflechner, Ch., Wieland, Ch., Spliethoff, H. Experimental assessment of an Organic Rankine Cycle with a partially evaporated working fluid. Applied Thermal Engineering, 2023, vol. 221, p. 119858. https://doi.org/10.1016/j.applthermaleng.2022.119858.
  8. Bu Dakka, B., Sultanguzin, I.A., Yavorovskiy, Yu.V., Kurzanov, S.Yu. Razrabotka kompleksnoy energeticheskoy ustanovki s rekuperatsiey teploty ukhodyashchikh gazov [Development of an Integrated Power Plant with Exhaust Gas Heat Recovery]. Vestnik MEI, 2025, no. 1, pp. 100–109. DOI: 10.24160/1993-6982-2025-1-100-109.
  9. Matuszewska, D. Economic Analysis of Gas Turbine Using to Increase Efficiency of the Organic Rankine Cycle. Sustainability, 2024, vol. 16, p. 75. https://doi.org/10.3390/ su16010075.
  10. Xia, X., Zhang, H., Wang, Z., Sun, T., Yang, C., Bo peng, Jiang, T. Comparative study of two novel composition adjustable organic Rankine cycle-vapor compression refrigeration systems. Thermal Science and Engineering Progress, 2025, vol. 57, p. 103179. https://doi.org/10.1016/j.tsep.2024.103179.
  11. Witanowski, Ł. Optimization of an Organic Rankine Cycle–Vapor Compression Cycle System for Electricity and Cooling Production from Low-Grade Waste Heat. Energies, 2024, vol. 17, p. 5566. https://doi.org/10.3390/en17225566
  12. Gonidaki, D., Bellos, E., Kaldellis, J.K. Design and Dynamic Simulation of a Solar-Driven Organic Rankine Cycle with Zeotropic Mixture. Sol. Energy, 2025, vol. 301, p. 113948.
  13. Arif, M.S., Kumar, L., Chandio, M.W., Raza, M.A., Harijan, K. Performance and economic analyses of organic ranki ne cycle integrated with parabolic trough solar collector using multiple dry working fluids. Environ Prog Sustainable Energy, 2025, vol. 44(6), p. e70079. DOI:10.1002/ep.70079
  14. Shalby, M., Marachli, A., Salah, A. Working fluid selection and performance analysis for subcritical organic Rankine cycles. Results in Engineering, 2025, vol. 25, p. 104120. https://doi.org/10.1016/j.rineng.2025.104120.
  15. Wang, J., Zhang, Y., Mei, C., Zhu, L. Operational flexibility-oriented selection of working fluid for organic Rankine cycles via Bayesian optimization. Computers & Chemical Engineering, 2025, vol. 197, p. 109043. https://doi.org/10.1016/j.compchemeng.2025.109043.
  16. Bellos, E. A detailed analysis of waste heat recovery organic Rankine cycle with partial evaporation and different working fluids. Applied Thermal Engineering, 2025, vol. 263, p. 125410. https://doi.org/10.1016/j.applthermaleng.2025.125410.
  17. Bu, S., Yang, X., Li, W., Su, C., Wang, X., Liu, X., Yu, N., Wang, G., Tang, J. Study and application of the shift-temperature of heating fluid for zeotropic mixtures in organic Rankine cycle. International Communications in Heat and Mass Transfer, 2023, vol. 145, part A, p. 106808. https://doi.org/10.1016/j.icheatmasstransfer.2023.106808.
  18. Mohan, S., Dinesha, P., Campana, P.E. ANN-PSO aided selection of hydrocarbons as working fluid for low-temperature organic Rankine cycle and thermodynamic evaluation of optimal working fluid. Energy, 2022, vol. 259, p. 124968. https://doi.org/10.1016/j.energy.2022.124968.
  19. Javed, S., Tiwari, A.K. Performance analysis of zeotropic mixture as a working fluid for medium temperature in regenerative Organic Rankine cycle. Process Safety and Environmental Protection, 2023, vol. 179, pp. 864–872. https://doi.org/10.1016/j.psep.2023.09.043.
  20. Feng, Y., Wang, Y., Yao, L., Xu, Jing-wei, Zhang, Fei-yang, He, Zhi-xia, Wang, Q., Ma, Jian-long. Parametric analysis and thermal-economical optimization of a parallel dual pressure evaporation and two stage regenerative organic Rankine cycle using mixture working fluids. Energy, 2023, vol. 263, part A, p. 125670. https://doi.org/10.1016/j.energy.2022.125670.
  21. Miao, Z., Wang, Z., Sabev Varbanov, P., Klemeš, J.J., Xu, J. Development of selection criteria of zeotropic mixtures as working fluids for the transcritical organic Rankine cycle. Energy, 2023, vol. 278, part A, p. 127811. https://doi.org/10.1016/j.energy.2023.127811.
  22. Wang, E., Mao, J., Zhang, B., Wang, Y. On the CAMD method based on PC-SAFT for working fluid design of a high-temperature organic Rankine cycle. Energy, 2023, vol. 263, part D, p. 125935. https://doi.org/10.1016/j.energy.2022.125935.
  23. Markides, C.N., Bardow, A., De Paepe, M., De Servi, C., Gross, J., Haslam, A.J., Lecompte, S., Papadopoulos, A.I., Oyewunmi, C.O. Working fluid and system optimisation of organic Rankine cycles via computeraided molecular design: A review. Progress in Energy and Combustion Science, 2025, vol. 107, p. 101201. https://doi.org/10.1016/j.pecs.2024.101201.
  24. Ovsyannik, A.V., Klyuchinskiy, V.P. Vybor, raschet i termodinamicheskiy analiz turboustanovok na organicheskom tsikle Renkina [Selection, Calculation and Thermodynamic Analysis of Turbine Units Based on the Organic Rankine Cycle]. Energetika. Izvestiya vysshikh uchebnykh zavedeniy i energeticheskikh obyedineniy SNG, 2022, vol. 65, no. 1, pp. 76–88. https://doi.org/10.21122/1029-7448-2022-65-1-76-88.
  25. Bekiloğlu, H.E., Bedir, H., Anlaş, G. Optimal selection of Organic Rankine cycle working fluids and geometric parameters of Condensers. Applied Thermal Engineering, 2025, vol. 280, part 2, p. 128242. https://doi.org/10.1016/j.applthermaleng.2025.128242.
  26. Malenkov, A.S. Razrabotka perspektivnoy sistemy teplokhladosnabzheniya na osnove absorbtsionnykh transformatorov teploty: diss. … kand. tekhn. nauk [Development of a promising heat and cold supply system based on absorption heat transformers. Cand. tech. sci. diss.]. Moscow, 2018. 188 p.
Key words in Russian: 
вторичные энергетические ресурсы, органический цикл Ренкина, слабая азотная кислота, низкокипящее рабочее тело
Key words in English: 
secondary energy resources, organic Rankine cycle, weak nitric acid, low-boiling working fluid
The DOI index: 
10.17588/2072-2672.2026.1.030-039
Downloads count: 
4