atw Vol. 63 (2018) | Issue 4 ı April
whole condensation phenomena and
flow morphologies by using GENTOP
concept. Further to the AIAD concept
which considers two continuous
fluids, the GENTOP approach is a
three field two fluid model and considers
also a poly dispersed phase.
Acknowledgments
This project is an ongoing project in
Helmholtz-Zentrum Dresden Rossendorf
(HZDR), which is funded by Bundesministerium
für Bildung und Forschung
(BMBF) under grant number
02NUK041B in Germany.
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Authors
Amirhosein Moonesi Shabestary,
Eckhard Krepper,
Dirk Lucas
Helmholtz-Zentrum
Dresden-Rossendorf
P.O.Box 510119
01314 Dresden, Germany
241
DECOMMISSIONING AND WASTE MANAGEMENT
The Decommissioning of the ENEA RB3
Research Reactor in Montecuccolino
F. Rocchi, C. M. Castellani, A. Compagno, I. Vilardi, R. Lorenzelli and A. Rizzo
The ENEA RB3 reactor was a 100 Wth research installation owned and operated by ENEA, in its center of Montecuccolino
near Bologna, from 1971 to 1989. It consisted of a cylindrical aluminium vessel, about 4.3 m high and 2.9 m in diameter,
which could host various types of fuel elements suspended from the top of a special adjustable rack and submerged into
moderating and cooling heavy water. Principal aim of the reactor was to provide neutronics data for the CIRENE NPP, a
SGHWR that was being designed and then partially built in Latina starting from 1979. The specific RB3 core, surrounded
by a graphite reflector and housed inside a concrete biological shielding, allowed to test easily very different fuel
element configurations by changing their pitches and by regulating the heavy water level inside the vessel. The reactor
design, similar to that of the ZED-II Canadian research facility, was originally developed by CEA for its Aquilon facility
in Saclay in 1956; in fact, through a special arrangement between ENEA and CEA, parts of the Aquilon facility were
ultimately donated to ENEA at the end of the 60s for the construction of RB3. In 1989, the RB3 reactor was shut down,
and in the late 2010 ENEA received by ministerial decree the authorization to its dismantling, with the aim of reaching
the “green field” status and with the unconditional release of its building, which is actually owned by the University of
Bologna. The dismantling activities started in May 2013 and were concluded at the end of 2014; after that, a campaign
for the radiological characterization of the building was initiated and concluded in June 2015. Now, all the necessary
site characterization activities are being conducted with the aim to present the results declaring the “green field” status
before the end of 2017. This paper will present the three main pillars of the decommissioning of RB3, namely the
strategy and methods for the dismantling, the strategy and methods for the radiological characterization of the building,
and finally the strategy and methods for the radiological characterization of the site. The radionuclide limits imposed
by the Italian Regulatory Body, together with the challenges encountered so far will be likewise shown and described.
Revised version of
a paper presented
at the Eurosafe,
Paris, France, 6 and 7
November 2017.
Decommissioning and Waste Management
The Decommissioning of the ENEA RB3 Research Reactor in Montecuccolino ı F. Rocchi, C. M. Castellani, A. Compagno, I. Vilardi, R. Lorenzelli and A. Rizzo
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