RRFM 2009 Transactions - European Nuclear Society

2009 CNEA REPORT ON PROGRESS ON THE DEVELOPMENT
OF LEU FUELS and TARGETS in ARGENTINA
S. BALART, P. CRISTINI, C. FERNÁNDEZ, A. G. GONZALEZ, M. LÓPEZ, H. TABOADA
Comisión Nacional de Energía Atómica
Av. Del Libertador 8250 (1429) Ciudad de Buenos Aires, , República Argentina
ABSTRACT
Since RRFM 2008 meeting, held in Hamburg, Germany, LEU fuel and target R&D
activities in CNEA were focused on: the commissioning for operation of the LEU
core converted RA-6 reactor, applied research and development on dispersed U-
Mo/Al(-Si) in Al cladding and monolithic U-Mo in Zry-4 cladding concepts to
understand reaction mechanisms in interaction zone formation and developing
promissory solutions for VHD monolithic and dispersed fuels and also CNEA
continued deploying R&D on LEU target and radiochemical technology for
radioisotope production, meeting international quality standards
1. Commissioning for operation for the RA-6 reactor with its new LEU core.
The RA-6 reactor is a pool-type 0.5MW one sited at San Carlos de Bariloche city,
Province of Río Negro, Argentina. During 2008 following tasks took place:
• Transport of the new LEU core from the ECRI plant sited at the Constituyentes
Atomic Center (close to Buenos Aires City) to the RA-6 reactor building. This new
core is made of 25 regular and control fuel assemblies with a dispersion of U3Si2
and Al powders, 4.8 gU/cm3 density, Cd wires were employed as neutron
absorbers.
• Preliminary tests for loading the new core started in September 18 th , 2008.
• Criticality start-up operations, started on January 19 th , 2009.
• Formal re-inauguration took place on March 16 th , 2009
This last operation completes the successful conversion process started in October 30 th ,
2005 with the signature of two contracts between CNEA and NNSA-DoE and comprised
swapping of HEU-LEU inventories, exportation of HEU SNF US-origin to USA, and
fabrication of the conversion core and new graphite reflectors and improvements on
primary and secondary loops.
2. Applied R&D on dispersed and monolithic U-Mo fuels.
• New results from out-of-pile tests using high intensity synchrotron X-rays diffraction
techniques performed in the LNLS Campinas, Brazil are presented. Characterization
of phases in the interaction layer, after 340ºC and 550ºC temperature treatment in
diffusion couple samples of U-Mo(-Zr) / Al(-Si) were optimized.
3. Development and irradiation of promissory solutions to VHD monolithic
and dispersed fuels technical problems
• Some improvements were done in the development of dispersed and monolithic
fuels made with Uranium-molybdenum alloy. The purpose is to have additional
alternatives to cover HEU-LEU conversion possibilities.
• The IAEA’s Technical Cooperation, the project ARG/4/092 to irradiate and PIE in a
high flux reactor a full scale fuel assembly prototype finished the tender process
and a provider was selected.
23 of 455