Izvestia Vysshikh Uchebnykh Zawedeniy. Yadernaya Energetika

The peer-reviewed scientific and technology journal. ISSN: 0204-3327

Irradiated fuel assembly 235u and 239pu non-destructive control methods comparative analysis at high gamma background level

6/21/2017 2017 - #02 Global safety, reliability and diagnostics of nuclear power installations

Kalenova M.Yu. Ananiev A.V. Baskov P.B. Sklyarov S.V.

DOI: https://doi.org/10.26583/npe.2017.2.04

UDC: 621.039.5

The potential small amounts (0,001 wt. %) of fissile materials determining methods at a high gamma background discussed and compared, the most appropriate for SFA nuclear material control was chosen. Passive neutron control possibility use for fissile materials Indirect detection (by 239Pu) with 242Cm, 244Cm pre-determination shown by numerical simulation. It is necessary to perform a number of conditions: 244Cm/242Cm/239Pu/240Pu ratio must be constant and known in advance; fissile materials should be evenly distributed within the container; background level should be significantly lower than its neutron radiation. Two detector types during passive method simulation setup were compared (3He-counters and 235U-based fission chambers). 3He-counters use prospects are shown. Neutron coincidence method with Am-Li and Pu-Be isotopic neutron sources does not allow to reliably determine the fissile materails content due to registered couples small amount. It was revealed that an active neutron monitoring method is optimal for the task. The calculated installation model shows more than 12 times signal excess on triple background error, indicating uniquely fissile materials (for 239Pu) minimum amount detection, wherein specimen vessel position does not affect on the recorded signal. Given the original structural material geometrical position heterogeneity in installation design amended as a pedestal moving bottom, allowing to set the specimen mass center in front of the 3He-counters and neutron source to increase signal registration efficiency, wherein it requires a preliminary gamma scanning height receptacle to determine structural materials spatial distribution. The direct detection, higher accuracy, less time detection and passive mode workability are proposed method advantages. After 239Pu determination evaluate the other isotopes content (Am, Cm, U, Np) is possible due to constant weight ratio 239Pu to detected actinide mass, depending on fuel burn-up degree and post-reactor excerpt. Thus, the proposed method allows to quickly find 239Pu, 242Cm, 244Cm content in SFA.

References

  1. Reilly Doug, Ensslin Norbert. Passive nondestructive assay of Nuclear Materials. Los Alamos National Laboratory, 1991. 700 p.
  2. Bezhunov G.M., Kulabukhov Yu.S., Matveenko I.P., Mychaylov G.M., Poplavko V.Y., Soloviev N.A. Aktivnaya sistema s impul’snym neytronnym generatorom dlya izmereniya kolichestva delyashchikhsya materialov v konteynerakh s otkhodam [Active system with a pulsed neutron generator for measuring the amount of fissionable materials in waste containers]. A tripartite seminar on the evaluation of the content and quantities of nuclear materials in circulation and waste, October 14-18, 2002. Obninsk. FEI Publ., 2003, pp. 205-217 (in Russian).
  3. Runkle R.C., Chichester D.L, Thompson S.J. Rattling nucleons: New developments in active interrogation of special nuclear material. Nuclear Instruments and Methods in Physics Research A. 2011, v. 663, pp. 75-95.
  4. Blokhin D.A., Chernov V.M., Blokhin A.I. Yaderno)fizicheskiye svoystva ferritno) martensitnykh staley EK)181 I EP)823 pri neytronnom obluchenii v reaktore BREST)300)OD [Nuclear-physical properties of ferritic-martensitic steels EC-181 and EP-823 under neutron rradiation in the BREST-300-OD reactor]. VANT. Ser. Materialovedeniye i novyye materialy, 2015, no. 3 (82), pp. 110-127 (in Russian).
  5. Vvedeniye v dozimetriyu i zashchita ot ioniziruyushchikh izlucheniy. [Introduction to dosimetry and protection from ionizing radiation.] St. Petersburg. Technical University Publ., 2008, 145p. (in Russian).
  6. Agostinelli S., Allison J.R., Amako K., +121 authors, last Zschiesche D. GEANT4 – a simulation toolkit. Nucl. Instr. & Meth. in Phys. Res. A. 2003, v. 506, pp. 250-303.
  7. Passive Non-Destructive Assay based on gamma-ray spectrometry to verify UO2 samples in the form of powder and pellet. Annals of Nuclear Energy. 2016, v. 87, p. 2.
  8. Dubia C., Ridnick T., Israelashvili I., Bagi J., Huszti J. A method for the estimation of fissile mass by measuring the number of neutron signals within a specific time interval. Nuclear Instruments and Methods in Physics Research. 2012, v. 673, pp. 111-115.
  9. Calculation of the Radionuclides in PWR Spent Fuel Samples for SFR Experiment Planning, Sandia National Laboratories, USA 2004. 103 p.
  10. Mason J.A., Bondar L., Hage W., Pedersen B.H. The advantages of neutron multiple correlation analysis. In: Proc. of the 15th ESARDA Symposium on Safeguards and Nuclear Material Management. Rome, 1993, p. 355.
  11. Tablitsy fizicheskikh velichin. [Tables of physical quantities. Handbook]. Moscow. Atomizdat Publ., 1976. 1009 p. (in Russian).
  12. Raoux A.C., Lyoussi A., Passard C. Transuranic waste assay by neutron interrogation and online prompt and delayed neutron measurement. Nuclear Instruments and Methods in Physics Research. 2002, v .207, pp 186-194.
  13. Jordan K.A., Vujic J., Gozani T. Remote thermal neutron die-away measurements to improve Differential Die-Away Analysis. Nuclear Instruments and Methods in Physics Research A. 2007, v. 576, pp. 404-406.
  14. Jordan K.A., Vujic J., Phillips E., Gozani T. Improving differential die-away analysis via the use of neutron poisons in detectors. Nuclear Instruments and Methods in Physics Research A. 2007, v. 576, pp. 404-406.
  15. Isakov А.I. Kazarnovski M.V. Medvedev U.A. Metelkin E.V.p Transient slowing down neutrons. Basic laws and some provisions. Moscow. Nauka Publ.,1984. 264 p. (in Russian).
  16. Bogolubov Ye.P., Korotkov S.A., Korytko L.A. Method and system based on pulsed neutron generator for fissile material detection in luggage. Nuclear Instruments and Methods in Physics Research B. 2004, v. 213, pp. 439-444.
  17. Batyaev V.F., Bochkarev O.V., Sklyarov S.V. Fissile materials detection via neutron differential die-away technique. International Journal of Modern Physics, Singapore. 2014, v. 27, pp. 1460130-1-1460130-8.
  18. Batyaev V.F., Bochkarev O.V., Sklyarov S.V., Romodanov V.L., Chernikova D.N. Monitoring fissile and matrix materials in closed containers by means of pulsed neutron sources. Atomic Energy. 2013, v. 115, no. 2, pp. 99-104.
  19. Prokhorov Yu.V. Veroyatnost’ i matematicheskaya statistika. [Probability and mathematical statistics]. Encyclopedia. Moscow. Bolshaya Rossiyskaya Encyclopediya Publ., 1999. 914 p. (in Russian).
  20. Kir’yanov G.I. Generatory bystrykh neytronov. [Fast neutron generators] Moscow. Energoatomizdat Publ., 1990. 224 p. (in Russian).
  21. Van Iseghem P. Overview of Radioactive Waste Characterization at SCK-CEN. IAEA LABONET Meeting, Vienna 2013.

fissile materials active control SFA structural materials 3He-counter gamma background