Performance evaluation of an improved pool scrubbing system for thermally-induced steam generator tube rupture accident in OPR1000
2
조회
0
다운로드
1
인용
0
참고문헌
키워드
초록
An improved mitigation system for thermally-induced steam generator tube rupture accidents was introduced to prevent direct environmental release of fission products bypassing the containment in the OPR1000. This involves injecting bypassed steam into the containment, cooling, and decontaminating it using a water coolant tank. To evaluate its performance, a severe accident analysis was performed using the MELCOR 2.2 code for OPR1000. Simulation results show that the proposed system sufficiently prevented the release of radioactive nuclides (RNs) into the environment via containment injection. The pool scrubbing system effectively decontaminated the injected RN and consequently reduced the aerosol mass in the containment atmosphere. However, the decay heat of the collected RNs causes re-vaporization. To restrict the re-vaporization, an external water source was considered, where the decontamination performance was significantly improved, and the RNs were effectively isolated. However, due to the continuous evaporation of the feed water caused by decay heat, a substantial amount of steam is released into the containment. Despite the slight pressurization inside the containment by the injected and evaporated steam, the steam decreased the hydrogen mole fraction, thereby reducing the possibility of ignition.
Abstract
An improved mitigation system for thermally-induced steam generator tube rupture accidents was introduced to prevent direct environmental release of fission products bypassing the containment in the OPR1000. This involves injecting bypassed steam into the containment, cooling, and decontaminating it using a water coolant tank. To evaluate its performance, a severe accident analysis was performed using the MELCOR 2.2 code for OPR1000. Simulation results show that the proposed system sufficiently prevented the release of radioactive nuclides (RNs) into the environment via containment injection. The pool scrubbing system effectively decontaminated the injected RN and consequently reduced the aerosol mass in the containment atmosphere. However, the decay heat of the collected RNs causes re-vaporization. To restrict the re-vaporization, an external water source was considered, where the decontamination performance was significantly improved, and the RNs were effectively isolated. However, due to the continuous evaporation of the feed water caused by decay heat, a substantial amount of steam is released into the containment. Despite the slight pressurization inside the containment by the injected and evaporated steam, the steam decreased the hydrogen mole fraction, thereby reducing the possibility of ignition.
참고문헌 (28)
- "Severe Accident Management Programmes for Nuclear Power Plants" (2009), INTERNATIONAL ATOMIC ENERGY AGENCY
- Nuclear Regulatory Commission, "Risk Assessment of Severe Accident-Induced Steam Generator Tube Rupture", ~ (1998)
- P. MacDonald, "Steam Generator Tube Failures", Nuclear Regulatory Commission (1996)
- A. Auvinen, "Steam generator tube rupture(SGTR)scenarios", Nucl. Eng. Des, 235(2–4), pp.457~472 (2005)
- S. I. Kim, "Analysis of steam generator tube rupture accident for OPR 1000 nuclear power plant", Nucl. Eng. Des, 382, pp.111403~ (2021)
- N. R. Commission, "Severe accident risks: an assessment for five US nuclear power plants: appendices A, B, and C", Nuclear Regulat. Commission (1990)
- W. Choi, "Effectiveness and adverse effects of invessel retention strategies under a postulated SGTR accident of an OPR1000", J. Nucl. Sci. Technol, 54(3), pp.337~347 (2017)
- Consequential SGTR Analysis for Westinghouse and Combustion Engineering Plants with Thermally Treated Alloy 600 and 690 Steam Generator Tubes, "S. Sancaktar", Office of Nuclear Regulatory Research, US Nuclear Regulatory Commission, ~ (2016)
- J. Song, "An analysis on the steam generator tube rupture events with core damage", Ann. Nucl. Energy, 150, pp.107877~ (2021)
- C. Fletcher, "SCDAP", RELAP5 Thermal-Hydraulic Evaluations of the Potential for Containment Bypass during Extended Station Blackout Severe Accident Sequences in a Westinghouse Four-Loop PWR, 2010
- T. Kim, "Investigation on Fission Products Release Mitigated by In-Containment Relief Valve under SGTR Accident", ~ (2018)
- I. Kaneko, "Experimental Study on Aerosol Removal Effect by Pool Scrubbing", 453~463 (1993)
- M. Y. Kim, "Containment aerosol characterization during nuclear power plant severe accident", Part. Sci. Technol, 34(5), pp.622~632 (2016)
- H. Bunz, "NAUA Mod 4: a code for calculating aerosol behaviour in LWR core melt accidents. Code Description and Users Manual", Kernforschungszentrum Karlsruhe, 1~66 (1983)
- H. -J. Allelein, "COCOSYS : status of development and validation of the German containment code system", Nucl. Eng. Des, 238(4), pp.872~889 (2008)
- User’s Manual for CONTAIN 1.1: a Computer Code for Severe Nuclear Reactor Accident Containment Analysis, "K. Murata", Sandia National Lab, ~ (1989)
- T. Lind, "A summary of fissionproduct-transport phenomena during SGTR severe accidents", Nucl. Eng. Des, 363, pp.110635~ (2020)
- MELCOR Computer Code Manuals, "L.L. Humphries", 93~2185, pp.SAND 2017-0455 O (2017)
- Commission, Computational Fluid Dynamics Analysis of Natural Circulation Flows in a Pressurized-Water Reactor Loop under Severe Accident Conditions, "U. N. R. Commission", ~, pp.NUREG-1922 (2010)
- C. Co, "Flow of Fluids through Valves, Fittings, and Pipe" (1988), Crane Company
- Y. H. Kim, "Experimental study of the nozzle size effect on aerosol removal by pool scrubbing", Nucl. Eng. Des, 385, pp.111544~ (2021)
- P.C. Owczarski, "SPARC-90: A Code for Calculating Fission Product Capture in Suppression Pools", 81. United States, 81~ (1991)
- J. Lopez-Jimenez, "Pool Scrubbing", Centro de Investigaciones Energeticas (1996)
- Y. Liao, "MELCOR analysis of steam generator tube creep rupture in station blackout severe accident", Nucl. Technol, 152(3), pp.302~313 (2005)
- L. S. Lebel, "Radioiodine in the atmosphere after the Fukushima Dai-ichi nuclear accident", J. Environ. Radioact, 151, pp.82~93 (2016)
- D. Paul, "Radionuclide Scrubbing in Water Pools-Gas-Liquid Hydrodynamics", ~ (1985)
- C. Berna, "Enhancement of the SPARC90code to pool scrubbing events under jet injection regime", Nucl. Eng. Des, 300, pp.563~577 (2016)
- Gauntt, MELCOR 1.8. 5 Modeling Aspects of Fission Product Release, Transport and Deposition an Assessment with Recommendations, "R. O. Gauntt", Sandia National Laboratories, ~ (2010)