GENERATION IV REACTOR COOLANT MONITORING USING ADONIS GAMMA RAYS SPECTROMETER Romain COULON Stéphane NORMAND IAEA TECHNICAL MEETING ON IN-PILE TESTING AND INSTRUMENTATION FOR DEVELOPMENT OF GENERATION-IV FUELS AND MATERIALS 21 ST TO 24 TH AUGUST 2012 PAGE 1
I. PRESENTATION 1ER SEPTEMBRE 2012 CEA 10 AVRIL 2012 PAGE 2
PRESENTATION OF THE CEA / LCAE Sensors and Electronics Architectures Laboratory Development of nuclear instruments (Industry, Security, Defense) Design of nuclear sensors (Nuclear Physics) Analyze of radioactive waste by IPA (Nuclear Physics) Synthetizes of fluorescents materials (Organic chemistry) Nano structuration of fluorescents materials (Optical physics) Development of Front-End electronics (Analog electronics) Development of DSP based on FPGA platform (Digital electronics) Development of signal processing algorithms (Mathematics statistics) Development of IHM, communications and dedicated mechanics (Software & mechanics) Industrial collaborations 1ER SEPTEMBRE 2012 CEA AUGUST 24 th 2012 PAGE 3
WHAT WE ARE DOING FOR REACTORS Reactor applications SUB-MARINE REACTORS Development of a high dynamics neutrons channel (AREVA-TA) System MARINE set into nuclear submarine (AREVA-TA) Upgrade of N16 leakage detection system (AREVA-TA) PRESSURIZED WATER REACTORS Qualification of AGR neutron flux detectors (EDF Energy) Upgrade of the scintillator based systems (EDF) Development of gamma spectroscopy systems for PWR (EDF) 2010 - Shutdown of PHENIX FOR SODIUM-COOLED FAST REACTORS (ASTRID) Design of a mono-mode neutron channel using third order cumulants (CEA DEN) Study performance of high temperature fission chambers (CEA DEN) Irradiation of materials using SAPHIR fast neutron flux (CEA DEN) Development of gamma spectroscopy systems for Gen. IV reactors (CEA DEN) 2020/25 Building of ASTRID 1ER SEPTEMBRE 2012 CEA AUGUST 24 th 2012 PAGE 4
II. SODIUM COOLANT GAMMA SPECTROSCOPY 1ER SEPTEMBRE 2012 CEA 10 AVRIL 2012 PAGE 5
ACTIVATION PRODUCTS ANALYSIS 1ER SEPTEMBRE 2012 CEA AUGUST 24 th 2012 PAGE 6
FISSION PRODUCTS ANALYSIS 1ER SEPTEMBRE 2012 CEA AUGUST 24 th 2012 PAGE 7
III. THE ADONIS SPECTROMETER 1ER SEPTEMBRE 2012 CEA 10 AVRIL 2012 PAGE 8
GAMMA SPECTROSCOPY Conventional spectrometers show difficulties to conduct on-line measurements when activity could change brutally Parameters of linear trapezoidal or cups filters are set in regards to experimental conditions As a compromise between energy resolution and count rate ability Could not maintain metrological stability when the dead time get above 40 % Intrinsic limitations of pile-up rejection life time correction and zeros dead time technics due to the previous pulse chapping A nonlinear filter has been developed by the CEA in order to achieve a robust measurement during transient activity and high count rates 1ER SEPTEMBRE 2012 CEA AUGUST 24 th 2012 PAGE 9
THE ADONIS NONLINEAR SMOOTHER A state model of the digitalized gamma signal E. Barat, NIM A567-1, 350-352,2006 Collection of charges Baseline evolution Electronic noise Observation Dynamic noise matrix r k = 1 during collection of charges r k = 0 no photon interactions 1ER SEPTEMBRE 2012 CEA AUGUST 24 th 2012 PAGE 10
THE ADONIS NONLINEAR SMOOTHER E. Barat, NIM A567-1, 350-352,2006 Use of a bimodal Kalman smoother (optimal estimation) Prediction of the signal Variance of the prediction Innovation (comparison perdition vs. observation) Variance of the innovation If then else Accurate dead time estimation CEA AUGUST 24 th 2012 1ER SEPTEMBRE 2012 PAGE 11
ADONIS GAMMA RAYS SPECTROMETER METROLOGICAL STABILITY MAINTAINED IN NPPs RADIATION ENVIRONNEMENT Conventional spectrometers are limited for industrial applications (process measurement) ADONIS shows metrological stability whatever the environnemental conditions Adaptive system: gives always an optimal filtering during transient activity (as power increase or FP release) 1ER SEPTEMBRE 2012 CEA AUGUST 24 th 2012 PAGE 12
IV. TESTS AT THE PHENIX SFR 1ER SEPTEMBRE 2012 CEA 10 AVRIL 2012 PAGE 13
TEST AT THE PHENIX SFR PROTOTYPE Fluorine 20 signal could performs a power measurement with An improve axial offset stability A limited temperature effect Experimentally measured at the French PHENIX reactor in 2009. 1ER SEPTEMBRE 2012 PAGE 14
RESULTS OBTAINED DURING PHENIX TESTS 24 Na Signal vs. Heat power Build-up of the 24 Na Impact of temperature 20 F Signal vs. Heat power Uncertainty : 28 % (non-optimized experimental set-up) No build-up & temperature effects Promising power tagging agent 1ER SEPTEMBRE 2012 PAGE 15
V. DESIGN OF A SPECTROMETRY SYSTEM FOR ASTRID SFR 1ER SEPTEMBRE 2012 CEA 10 AVRIL 2012 PAGE 16
A SYSTEM FOR THE GEN. IV ASTRID REACTOR We are developing a spectroscopy system for the future French Generation IV prototype ASTRID (under investigation) 1ER SEPTEMBRE 2012 PAGE 17
CLAD FAILURE DETECTION USING SHORT LIFES FISSION PRODUCTS Fission products could not be measured by conventional spectrometers due to the high sodium 24 gamma activity So, clad failure are detected by delayed neutrons detection (DND) or by degasing and decaying of the coolant activity A direct measurement using ADONIS spectrometer could improve the early detection of clad failures 1ER SEPTEMBRE 2012 PAGE 18
VI. CONCLUSION 1ER SEPTEMBRE 2012 CEA 10 AVRIL 2012 PAGE 19
CONCLUSION REACTOR COOLANT MONITORING Thanks to the stability of ADONIS at high count rates it is now possible to assure a robust gamma spectroscopy to monitor reactor coolants The system has already shows is ability to monitor the reactor power by fluorine 20 measurement (at PHENIX) The ADONIS system is particularly adapted to monitor fast activity changing as failure analysis. We are searching a facility to test ADONIS for monitoring clad failures (water or sodium loops ). 1ER SEPTEMBRE 2012 CEA 10 AVRIL 2012 PAGE 20
Thanks for your attention. PAGE 21 CEA 10 AVRIL 2012 1ER SEPTEMBRE 2012 Commissariat à l énergie atomique et aux énergies alternatives Centre de Saclay 91191 Gif-sur-Yvette Cedex T. +33 (0)1 69 08 84 91 Etablissement public à caractère industriel et commercial RCS Paris B 775 685 019 DRT / LIST DCSI LCAE
A.I. TESTS AT SAPHIR ACCELERATOR 1ER SEPTEMBRE 2012 CEA 10 AVRIL 2012 PAGE 22
SAPHIR : une plate-forme dédiée à la mesure nucléaire Développement des méthodes IPA IGA SAPHIR Couplage des méthodes non-destructives passives et actives Plate-forme de test pour codes et systèmes nouvelle génération : SINBAD, PING, ADONIS Tout juste 10 ans
Installation SAPHIR Caractéristiques de l installation Système d Activation PHotonique et d IRradiation SAPHIR Dispositif construit autour d un LINAC Création de photons de haute énergie par Bremsstrahlung sur une cible en tungstène Caractéristiques du LINAC : irradiation pulsée (25 Hz ou 50 Hz, impulsions de 2,5 µs), énergie moyenne des électrons comprise entre 12 MeV et 20 MeV Débit de dose à l isocentre (1 m dans axe de la cible) : ~12 Gy.min -1
Installation SAPHIR Caractéristiques de l installation Convoyeur pneumatique permettant d irradier les échantillons et de les transporter en quelques secondes en zone de comptage Convoyeur Cible Convoyeur mécanique dans salle d irradiation : masse jusqu à 5 tonnes, mouvement translation/rotation Détecteurs neutrons / gamma disponibles ( 3 He, HPGe, LaBr 3, BGO) Mesure de débit de dose en ligne via chambre PTW Moyen d imagerie haute énergie via l utilisation d un EPID Possibilité d irradier en mode électrons ou en mode neutrons (flux supérieur à celui d un générateur neutrons)
Conveyor Target
VALIDATION OF THE METHODS Waiting ASTRID, we regarding other facilities to continue testing ADONIS for NPP s application First tests of sodium activation using an electron accelerator The SAPHIR facility Set-up of the experimental test SEPTEMBER 1, 2012 PAGE 27
GAMMA SPECTRUM AFTER IRRADIATION OF NAOH We investigate the possibility to build a water and a sodium loops at the SAPHIR accelerator. 1ER SEPTEMBRE 2012 PAGE 28