AMONYAK OKSİDASYON REAKTÖRÜ ISI DEĞİŞTİRİCİLERİNİN İYİLEŞTİRİLMESİYLE PROSES GAZI SOĞUTMA PERFORMANSININ ARTIRILMASININ ARAŞTIRILMASI

Year 2025, Volume: 45 Issue: 1, 97 - 110, 07.04.2025

Oğuzhan Erbaş , Fadime Menekşe İkbal

https://doi.org/10.47480/isibted.1566904

Abstract

Bu çalışmada, 610 ton/gün kapasiteli bir nitrik asit üretim tesisindeki 3,8 m çapında ve 6,5 m yüksekliğindeki endüstriyel tip amonyak oksidasyon reaktörünün ısı değiştiricilerini iyileştirerek, NOx gazının soğutma performansının artırılması amaçlanmıştır. Reaktör, % 100 HNO3, %56 seyreltilmiş nitrik asit ve 33 ton/saat aşırı ısıtılmış buhar üretmektedir. Bu amaçla, eşanjör boruları arasındaki yatay ve düşey mesafe, boru çapları ve eşanjör paketleri (ön buharlaştırıcı, aşırı ısıtıcı, buharlaştırıcı, ekonomizer) arasındaki mesafenin ayrı ayrı kullanıldığı parametrik analiz çalışması, Ansys Fluent programı yardımıyla yapılmış ve akış özellikleri ile performans değerleri incelenmiştir. En iyi soğutma performansı farklı parametrik çalışmalar sonucunda; ısı değiştirici boruları arasında yatay olarak 56 mm mesafede proses gazı sıcaklığının 270,5 0C elde edildiği çalışma ile sağlanmıştır. Böylece, reaktörün gaz çıkış sıcaklığında % 9,1'lik bir azalma sağlanmıştır. Diğer parametrik çalışmalarda ise en düşük proses gazı sıcaklıkları; ısı değiştirici paketleri arasındaki mesafe (L) için 323,2 0C, ısı değiştirici boruları arasındaki dikey mesafe (b) için 318,4 0C ve ısı değiştirici boru çapı (D) için 296,6 0C olarak bulunmuştur. Ayrıca, en iyi soğutma performansını sağlayan CFD simülasyon sonuçları, gerçek işletme verileriyle (SCADA verileri ile) karşılaştırıldığında; amonyak oksidasyon reaktöründe soğutucu akışkan çıkış sıcaklığı ekonomizerde %8,2, buharlaştırıcıda %9,7 ve süperheater'da %4,3 artmıştır.

Keywords

Proses Gaz Soğutma, Oksidasyon Reaktörü, Isı Eşanjörü, CFD Analizi

INVESTIGATION OF INCREASING PROCESS GAS COOLING PERFORMANCE BY IMPROVING AMMONIA OXIDATION REACTOR HEAT EXCHANGERS

Abstract

This study aims to increase the cooling performance of NOx gas by improving the heat exchangers of an industrial-type ammonia oxidation reactor with a diameter of 3.8 m and a height of 6.5 m in a nitric acid production plant with a capacity of 610 tons/day. The reactor produces 100% HNO3, 56% diluted nitric acid, and 33 tons/hour of superheated steam. To this end, the parametric analysis study, in which the horizontal and vertical distance between the exchanger tubes, the pipe diameters, and the distance between the exchanger packages (pre-evaporator, superheater, evaporator, economizer) were used separately, was carried out with the help of Ansys Fluent program and the flow properties and performance values were examined. The best cooling performance (for the inner part of the ammonia oxidation reactor) resulted from different parametric studies; there was a study in which the process gas temperature was obtained at 270.510C with a 56 mm horizontal distance between the heat exchanger tubes (a). Thus, a 9.1% decrease in the actual gas outlet temperature of the operating reactor was achieved. In other parametric studies, the lowest process gas temperatures are; it was found to be 323.200C for the distance between heat exchanger packages (L), 318.42 0C for the vertical distance between heat exchanger tubes (b), and 296.67 0C for the heat exchanger tube diameter (D). In addition, when the CFD simulation results, which provide the best cooling performance, are compared with actual operating data (SCADA online data), In the ammonia oxidation reactor, the fluid outlet temperature increased by 8.2% in the economizer, 9.7% in the evaporator and 4.3% in the superheater.

Keywords

Process Gas Cooling, Oxidation Reactor, Heat Exchanger, CFD Analysis

References

• Abbasfard, H., Ghanbari, M., Ghasemi, A., Ghader, S., Rafsanjani, H. H., & Moradi, A. (2012). Failure analysis and modeling of superheater tubes of a waste heat boiler thermally coupled in an ammonia oxidation reactor. Engineering Failure Analysis, 26, 285-292. https://doi.org/10.1016/j.engfailanal.2012.06.012
• Abbasfard, H., Ghanbari, M., Ghasemi, A., Ghahraman, G., Jokar, S. M., & Rahimpour, M. R. (2014). CFD modeling of flow mal-distribution in an industrial ammonia oxidation reactor: A case study. Applied thermal engineering, 67(1-2), 223-229. https://doi.org/10.1016/j.applthermaleng.2014.03.035
• Amirsadat, S. M., Azari, A., Nazari, M., & Akrami, M. (2024). Conversion augmentation of an industrial NH3 oxidation reactor by geometry modification to improve the flow and temperature pattern uniformity using CFD modeling. Chemical Engineering Journal Advances, 19, 100629. https://doi.org/10.1016/j.ceja.2024.100629
• Ardy, H., Putra, Y. P., Anggoro, A. D., & Wibowo, A. (2021). Failure analysis of primary waste heat boiler tube in ammonia plant. Heliyon, 7(2). https://doi.org/10.1016/j.heliyon.2021.e06151
• Bagheri, H., Bagheri, S., Hashemipour, H., & Rahimpour, M. R. (2024). Modeling and optimization of ammonia reactor. In Progresses in Ammonia: Science, Technology and Membranes (pp. 173-204). Elsevier. https://doi.org/10.1016/B978-0-323-88516-4.00001-9
• Belghaieb, J., Dkhil, O., Elhajbelgacem, A., Hajji, N., & Labidi, J. (2010). Energy optimization of a network of exchangers-reactors in a nitric acid production plant. Chemical Engineering, 21. https://doi.org/10.3303/CET1021046
• Chatterjee, I. B., & Joshi, J. B. (2008). Modeling, simulation, and optimization: Mono pressure nitric acid process. Chemical Engineering Journal, 138(1-3), 556-577. https://doi.org/10.1016/j.cej.2007.07.064
• Chernyshev, V. I., & Zjuzin, S. V. (2001). Improved start-up for the ammonia oxidation reaction. Platinum Metals Review, 45(1), 22-30.
• Colak, A. B., & Arslan, O. (2024). Numerical analysis-based performance assessment of the small-scale organic Rankine cycle turbine design for residential applications. Thermal Science and Engineering Progress, 51, 102626. https://doi.org/10.1016/j.tsep.2024.102626
• Dong, Y., Zhang, D., Li, D., Jia, H., & Qin, W. (2023). Control of Ostwald ripening. Science China Materials, 66(3), 1249-1255. https://doi.org/10.1007/s40843-022-2233-3
• Elsayed, S., & Farag, H. A. (2023). Modelling of an Industrial Reactor for Ammonia Oxidation. ERJ. Engineering Research Journal, 46(4), 451-456. https://doi.org/10.21608/erjm.2023.142966.1177
• Enger, B. C., Auvray, X., Lødeng, R., Menon, M., Waller, D., & Rønning, M. (2018). Catalytic oxidation of NO to NO2 for nitric acid production over a Pt/Al2O3 catalyst. Applied Catalysis A: General, 564, 142-146. https://doi.org/10.1016/j.apcata.2018.07.019
• Fajardo, J., Valle, H., & Buelvas, A. (2018). Avoidable and Unavoidable Exergetic Destruction Analysis of a Nitric Acid Production Plant. In ASME International Mechanical Engineering Congress and Exposition (Vol. 52088, p. V06BT08A009). American Society of Mechanical Engineers. https://doi.org/10.2298/TSCI120503181V
• Fíla, V., & Bernauer, B. (1994). A mathematical model of a gauze reactor for the ammonia oxidation. Collection of Czechoslovak chemical communications, 59(4), 855-874. https://doi.org/10.1135/cccc19940855
• García-Ruiz, P., Uruén, M., Abián, M., & Alzueta, M. U. (2023). High pressure ammonia oxidation in a flow reactor. Fuel, 348, 128302. https://doi.org/10.1016/j.fuel.2023.128302
• Grande, C. A., Andreassen, K. A., Cavka, J. H., Waller, D., Lorentsen, O. A., Øien, H., ... & Modeshia, D. (2018). Process intensification in nitric acid plants by catalytic oxidation of nitric oxide. Industrial & Engineering Chemistry Research, 57(31), 10180-10186. https://doi.org/10.1021/acs.iecr.8b01483
• Hannevold, L., Nilsen, O., Kjekshus, A., & Fjellvåg, H. (2005). Reconstruction of platinum–rhodium catalysts during oxidation of ammonia. Applied Catalysis A: General, 284(1-2), 163-176. https://doi.org/10.1016/j.apcata.2005.01.033
• Heck, R. M., Bonacci, J. C., Hatfield, W. R., & Hsiung, T. H. (1982). A new research pilot plant unit for ammonia oxidation processes and some gauze data comparisons for nitric acid process. Industrial & Engineering Chemistry Process Design and Development, 21(1), 73-79. https://doi.org/10.1021/i200016a014
• Hernández, A. B., Fajardo, J. G., Barreto, D., Caballero, G. E. C., Escorcia, Y. C., Tovar, C. R. V., & Hernández, Y. G. (2021). Conventional and advanced exergoeconomic indicators of a nitric acid production plant concerning the cooling temperature in compression Train's intermediate stages—case Studies in Thermal Engineering, 27, 101214. https://doi.org/10.1016/j.csite.2021.101214
• Holma, H., & Sohlo, J. (1979). A mathematical model of an absorption tower of nitrogen oxides in nitric acid production. Computers & Chemical Engineering, 3(1-4), 135-141. https://doi.org/10.1016/0098-1354(79)80024-1
• Hung, C. M. (2008). Catalytic wet oxidation of ammonia solution with platinum-palladium-rhodium composite oxide catalyst. J. Environ. Eng. Manage, 18(2), 85-91.
• Il'chenko, N. I., & Golodets, G. I. (1975). Catalytic oxidation of ammonia: II. Relationship between catalytic properties of substances and surface oxygen bond energy. General regularities in catalytic oxidation of ammonia and organic substances. Journal of Catalysis, 39(1), 73-86. https://doi.org/10.1016/0021-9517(75)90283-3
• Juangsa, F. B., & Aziz, M. (2019). Integrated system of thermochemical cycle of ammonia, nitrogen production, and power generation. International Journal of Hydrogen Energy, 44(33), 17525-17534. https://doi.org/10.1016/j.ijhydene.2019.05.110
• Kayapinar, O., Arslan, A. E., Arslan, O., & Genc, M. S. (2024). Multi-criteria analysis on the simulation-based optimal design of a new stack-type natural ventilation system for industrial buildings. Thermal Science and Engineering Progress, 51, 102657. https://doi.org/10.1016/j.tsep.2024.102657
• Kirova-Yordanova, Z. (2011). Application of the exergy method to the environmental impact estimation: The nitric acid production as a case study. Energy, 36(6), 3733-3744. https://doi.org/10.1016/j.energy.2010.12.039
• Kishan, R., Singh, D., & Sharma, A. K. (2020). CFD Analysis of heat exchanger models designs using Ansys fluent—International Journal of Mechanical Engineering and Technology, 11(2). https://www.doi.org/10.34218/IJMET.11.2.2020.001
• Kraehnert, R., & Baerns, M. (2008). Kinetics of ammonia oxidation over Pt foil studied in a micro-structured quartz-reactor. Chemical engineering journal, 137(2), 361-375. https://doi.org/10.1016/j.cej.2007.05.005
• Lim, J., Fernández, C. A., Lee, S. W., & Hatzell, M. C. (2021). Ammonia and nitric acid demand for fertilizer use in 2050. ACS Energy Letters, 6(10), 3676-3685. https://doi.org/10.1021/acsenergylett.1c01614
• Mewada, R. K., & Nimkar, S. C. (2015). Minimization of exergy losses in mono high-pressure nitric acid process. International Journal of Exergy, 17(2), 192-218. https://doi.org/10.1504/IJEX.2015.069990
• Moszowski, B., Wajman, T., Sobczak, K., Inger, M., & Wilk, M. (2019). The analysis of distribution of the reaction mixture in ammonia oxidation reactor. Polish Journal of Chemical Technology, 21(1), 9-12. https://doi.org/10.2478/pjct-2019-0002
• Nascimento, G. R., & Dangelo, J. V. (2024). Operating parameters analysis of a nitric acid plant to increase production and reduce NOx gases emission. Chemical Engineering and Processing-Process Intensification, 196, 109662. https://doi.org/10.1016/j.cep.2024.109662
• Neumann, N. C., Baumstark, D., Martínez, P. L., Monnerie, N., & Roeb, M. (2024). Exploiting synergies between sustainable ammonia and nitric acid production: A techno-economic assessment. Journal of Cleaner Production, 438, 140740. https://doi.org/10.1016/j.jclepro.2024.140740
• Noorollahi, Y., Saeidi, R., Mohammadi, M., Amiri, A., & Hosseinzadeh, M. (2018). The effects of ground heat exchanger parameters changes on geothermal heat pump performance–A review. Applied Thermal Engineering, 129, 1645-1658. https://doi.org/10.1016/j.applthermaleng.2017.10.111
• Pfefferle, L. D., & Pfefferle, W. C. (1987). Catalysis in combustion. Catalysis Reviews Science and Engineering, 29(2-3), 219-267. https://doi.org/10.1080/01614948708078071
• Pottbacker, J., Jakobtorweihen, S., Behnecke, A. S., Abdullah, A., Özdemir, M., Warner, M., ... & Horn, R. (2022). Resolving gradients in an ammonia oxidation reactor under industrial conditions: A combined experimental and simulation study. Chemical engineering journal, 439, 135350. https://doi.org/10.1016/j.cej.2022.135350
• Process Gas Coolers Operation and Maintenance Manual (2024). Istanbul Fertilizer Industry Inc. Kutahya Production Facilities.
• Rajeshkumar, M., Logesh, K., Thangaraj, M., & Govindan, S. (2021). Heat transfer study on finned tube heat exchanger using CFD. International Journal of Ambient Energy, 42(3), 239-243 https://doi.org/10.1080/01430750.2018.1542621
• Sadykov, V. A., Isupova, L. A., Zolotarskii, I. A., Bobrova, L. N., Noskov, A. S., Parmon, V. N., ... & Lunin, V. V. (2000). Oxide catalysts for ammonia oxidation in nitric acid production: properties and perspectives. Applied Catalysis A: General, 204(1), 59-87. https://doi.org/10.1016/S0926-860X(00)00506-8
• Salam, M. A., Nassef, E., Elkheriany, E., & El Tawel, Y. (2016). Modeling and Simulation of Gauze Reactor of Ammonia Oxidation. American Journal of Chemical Engineering, 4(1), 16-22. https://doi.org/10.11648/j.ajche.20160401.13
• Scheuer, A., Hirsch, O., Hayes, R., Vogel, H., & Votsmeier, M. (2011). Efficient simulation of an ammonia oxidation reactor using a solution mapping approach. Catalysis Today, 175(1), 141-146. https://doi.org/10.1016/j.cattod.2011.03.036
• Schumacher, K., Engelbrecht, N., Everson, R. C., Friedl, M., & Bessarabov, D. G. (2019). Steady-state and transient modelling of a microchannel reactor for coupled ammonia decomposition and oxidation. International Journal of Hydrogen Energy, 44(13), 6415-6426. https://doi.org/10.1016/j.ijhydene.2019.01.132
• Song, Y., Hashemi, H., Christensen, J. M., Zou, C., Marshall, P., & Glarborg, P. (2016). Ammonia oxidation at high pressure and intermediate temperatures. Fuel, 181, 358-365. https://doi.org/10.1016/j.fuel.2016.04.100
• Srinivasan, R., Hsing, I. M., Berger, P. E., Jensen, K. F., Firebaugh, S. L., Schmidt, M. A., ... & Ryley, J. F. (1997). Micromachined reactors for catalytic partial oxidation reactions. AIChE Journal, 43(11), 3059-3069. https://doi.org/10.1016/j.ces.2007.09.021
• Stagni, A., Cavallotti, C., Arunthanayothin, S., Song, Y., Herbinet, O., Battin-Leclerc, F., & Faravelli, T. (2020). An experimental, theoretical and kinetic-modeling study of the gas-phase oxidation of ammonia. Reaction Chemistry & Engineering, 5(4), 696-711. https://doi.org/10.1039/C9RE00429G
• Wiser, Artur M. (2020), Investigation of the Industrial NH3 Oxidation by CFD Simulations Including Detailed Surface Kinetics (Ph.D. thesis), Technische Universität Darmstadt. https://doi.org/10.25534/tuprints-00017208
• Zhan, H., Li, S., Yin, G., Hu, E., & Huang, Z. (2024). Experimental and kinetic study of ammonia oxidation and NOx emissions at elevated pressures. Combustion and Flame, 263, 113129. https://doi.org/10.1016/j.ijhydene.2024.12.214