HAZOP-Based Radiological Risk Assessment of Pebble Bed Fuel Handling Systems

Rusbani Kurniawan, Egnes Ekaranti, Agus Nur Rachman, Eka Djatnika Nugraha, I Wayan Ngarayana, Zulkifli Djunaidi

DOI: http://dx.doi.org/10.55981/tdm.2024.7016


The High-Temperature Gas-Cooled Reactor (HTGR), a promising candidate for Generation IV nuclear reactors, boasts superior inherent passive safety features and a continuous fuel handling system. This system employs multi-pass cycles, utilizing pneumatic and gravitational mechanisms to feed, circulate, and unload the pebble bed fuel element. This paper presents a descriptive analysis assessing the safety risk of the fuel handling system design in HTR-10. The Hazard and Operability Study (HAZOP) methodology is employed to identify hazard parameters, deviation limitations, causes, impacts, and potential risks to the system’s main components. The establishment of probability scales, consequence criteria, risk level ratings, and control activities adheres to the ISO 31000 standard. Primary data were gathered through expert interviews, while secondary data were sourced from design layout documentation, literature reviews, and safety analysis reports. Six main components - the elevator, core, singulator, failed fuel separator, burnup measurement, and distributor - were selected as assessment nodes from the piping and instrumentation diagram. The assessment revealed that each node initially presented a moderate to extreme risk potential (risk level rating C to E). However, after applying the effectiveness index of the designed control, the residual risk for all nodes was reduced to an acceptable limit (risk rating A - very low). Therefore, the fuel handling system design already incorporates adequate control activities to mitigate potential safety risks due to system component failure. As safety risk assessment is dynamic, it should be reviewed periodically or whenever there are design changes at any project stage. This ensures the safety risk magnitude is consistently known and managed effectively.

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I. Pioro, Handbook of Generation IV Nuclear Reactors: A Guidebook. Woodhead Publishing, 2022.

S. M. Alshehri, I. A. Said, and S. Usman, “A review and safety aspects of modular high‐temperature gas‐cooled reactors,” Int. J. Energy Res., vol. 45, no. 8, pp. 11479–11492, 2021.

W. Vechgama, K. Silva, A. Pechrak, and S. Wetchagarun, “Application of Hazard and Operability Technique to Level 1 Probabilistic Safety Assessment of Thai Research Reactor-1/Modification 1: Internal Events and Human Errors,” Prog. Nucl. Energy, vol. 138, p. 103838, 2021.

J. I. Single, J. Schmidt, and J. Denecke, “State of research on the automation of HAZOP studies,” J. Loss Prev. Process Ind., vol. 62, p. 103952, 2019.

ISO, “ISO 31000:2018,” Geneva Int. Organ. Stand., 2018.

A. Raveendran, V. R. Renjith, and G. Madhu, “A comprehensive review on dynamic risk analysis methodologies,” J. Loss Prev. Process Ind., vol. 76, p. 104734, 2022.

R. Cormier and J. Londsdale, “Risk assessment for deep sea mining: An overview of risk,” Mar. Policy, vol. 114, p. 103485, 2020.

X. Gao, A. A. A. Raman, H. F. Hizaddin, M. M. Bello, and A. Buthiyappan, “Review on the inherently safer design for chemical processes: past, present and future,” J. Clean. Prod., vol. 305, p. 127154, 2021.

K. Widiyati and S. Dibyo, “A Review on Pneumatic Transportation in The Design of Fuel Handling System in RDE-HTGR,” in Journal of Physics: Conference Series, 2019, vol. 1198, no. 2, p. 22068.

J. G. Liu, H. L. Xiao, and C. P. Li, “Design and full scale test of the fuel handling system,” Nucl. Eng. Des., vol. 218, no. 1–3, pp. 169–178, 2002.

R. S. Almusafir, A. A. Jasim, and M. H. Al-Dahhan, “Review of the Fluid Dynamics and Heat Transport Phenomena in Packed Pebble Bed Nuclear Reactors,” Nucl. Sci. Eng., vol. 197, no. 6, pp. 1001–1037, 2023.

E. H. Kwapis, H. Liu, and K. C. Hartig, “Tracking of individual TRISO-fueled pebbles through the application of X-ray imaging with deep metric learning,” Prog. Nucl. Energy, vol. 140, p. 103913, 2021.

A. J. Huning, S. Chandrasekaran, and S. Garimella, “A review of recent advances in HTGR CFD and thermal fluid analysis,” Nucl. Eng. Des., vol. 373, p. 111013, 2021.

J. Guo, Y. Wang, H. Zhang, M. Cui, and F. Li, “Challenges and progress of uncertainty analysis for the pebble-bed high-temperature gas-cooled reactor,” Prog. Nucl. Energy, vol. 138, p. 103827, 2021.

Y. H. Fang, X. X. Li, C. G. Yu, J. G. Chen, and X. Z. Cai, “Fuel pebble optimization for the thorium-fueled Pebble Bed Fluoride salt-cooled high-temperature reactor (PB-TFHR),” Prog. Nucl. Energy, vol. 108, pp. 179–187, 2018.

N. R. Brown, “A review of in-pile fuel safety tests of TRISO fuel forms and future testing opportunities in non-HTGR applications,” J. Nucl. Mater., vol. 534, p. 152139, 2020.

N. Gui, S. Jiang, X. Yang, and J. Tu, “A review of recent study on the characteristics and applications of pebble flows in nuclear engineering,” Exp. Comput. Multiph. Flow, vol. 4, no. 4, pp. 339–349, 2022.

T. Li et al., “Experimental and numerical study of coarse particle conveying in the small absorber sphere system: Overview and some recent CFD-DEM simulations,” Nucl. Eng. Des., vol. 357, p. 110420, 2020.

Q. Sun, W. Peng, S. Yu, and K. Wang, “A review of HTGR graphite dust transport research,” Nucl. Eng. Des., vol. 360, p. 110477, 2020.

M. Wu, N. Gui, X. Yang, J. Tu, and S. Jiang, “Numerical investigation of flow characteristics and packing structure of binary-sized pebble flow in a circulating pebble bed,” Prog. Nucl. Energy, vol. 150, p. 104312, 2022.

M. Wei, Y. Zhang, X. Wu, and L. Sun, “A parametric study of graphite dust deposition on high-temperature gas-cooled reactor (HTGR) steam generator tube bundles,” Ann. Nucl. Energy, vol. 123, pp. 135–144, 2019.

S. Jiang, J. Tu, X. Yang, and N. Gui, “A review of pebble flow study for pebble bed high temperature gas-cooled reactor,” Exp. Comput. Multiph. Flow, vol. 1, pp. 159–176, 2019.

P. A. Demkowicz, B. Liu, and J. D. Hunn, “Coated particle fuel: Historical perspectives and current progress,” J. Nucl. Mater., vol. 515, pp. 434–450, 2019.

R. H. Mohammed, A. S. Alsagri, and X. Wang, “Performance improvement of supercritical carbon dioxide power cycles through its integration with bottoming heat recovery cycles and advanced heat exchanger design: a review,” Int. J. Energy Res., vol. 44, no. 9, pp. 7108–7135, 2020.


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