Dismantling of large components from PHENIX reactor
International conference on Fast reactors and related
Fuel Cycles: Safe technologies and sustainable Scenarios
(FR13)
Paper T1-CN-199/442:
“Dismantling of large components from PHENIX reactor”
CEA MARCOULE – Centrale PHENIX
Technical Session 9.2 / 6 March 2013
1
Dismantling of large components from PHENIX reactor
The PHENIX reactor was shut down in 2009.
The cleaning and dismantling preparation
operations are underway.
These operations include dealing with large
removable components such as primary
coolant
pumps,
intermediate
heat
exchanger and heat exchanger blanking
device (DOTE).
This presentation describes the waste transformation operations performed on a
large component, from its extraction from the reactor core until transformation to
waste for disposal.
CEA MARCOULE – Centrale PHENIX
Technical Session 9.2 / 6 March 2013
2
Dismantling of large components from PHENIX reactor
Before 2009, all of the large components were dismantling (several cuts by plasma)
and conditioned in metal containers according Low Level and Intermediate Level
Short Lived (LIL-SL) waste’s specifications. These operations induced several cuttings
and thus consumed time and induced exposition of the operators.
In order to reduce the dose and the cost due to the treatment of the component,
the objective is now to send the DOTE in one single part to the CIRES (Very Low
Level, VLL, waste repository).
2011
2008
CEA MARCOULE – Centrale PHENIX
Technical Session 9.2 / 6 March 2013
3
Dismantling of large components from PHENIX reactor
A DOTE or dummy intermediate heat exchanger replaces an
intermediate heat exchanger in order to first plug the slab
penetration initially intended for an exchanger by providing a
radiation shield and second make a leak tightness between the
hot and cold headers with an argon cap.
DOTE
Weight: 14 t
Lenght : 7m
Diameter : 1,5m
CEA MARCOULE – Centrale PHENIX
Technical Session 9.2 / 6 March 2013
4
Dismantling of large components from PHENIX reactor
DIFFERENT STEPS OF THE TREATMENT
OF THE DOTE IN SINGLE PART:
 Washing the component
 Characterisation

Acceptance file to ANDRA

Preparation of the component

Fitting out of a single part
 Deliver to the CIRES (Waste repository)
CEA MARCOULE – Centrale PHENIX
Technical Session 9.2 / 6 March 2013
5
Dismantling of large components from PHENIX reactor
Washing
The component is then transferred to washing pits where it undergoes a series of
washing baths in order to remove sodium residue.
The washing process implies gradually destroying the residual sodium using water
in the form of aerosols shaped by a carrier gas, CO2, which favours the
neutralization of sodium hydroxide produced by transforming it into carbonate.
After direct spraying of steam, the component is dried using nitrogen and visually
inspected. Lastly, it is rinsed and possibly submerged.
The DOTE in a washing pit
CEA MARCOULE – Centrale PHENIX
Technical Session 9.2 / 6 March 2013
6
Dismantling of large components from PHENIX reactor
Characterisation
A mapping of the component is carried out after the washing process (dose rate and
contamination).
Then a gamma spectrometry characterization is performed when removed from the
wash pit. The component is measured by sections to determine the parts pertaining to
VLL and LL/ML channels. It was only after obtaining the measurement results that
processing scenario is defined.
=> The DOTE, in its entirety, has VLL ranking and will be processed as a single part.
Gamma spectrometry
CEA MARCOULE – Centrale PHENIX
Radiologic map
Technical Session 9.2 / 6 March 2013
7
Dismantling of large components from PHENIX reactor
Acceptance file to ANDRA
Acceptance of the single part at the CIRES involves considerable preparatory work
consisting of specific meetings and discussion with ANDRA to establish the
processing procedure as well as all the characterization stages and also the type of
transport required.
An acceptance file is drafted by the plant and must be drawn up in collaboration
with ANDRA.
CEA MARCOULE – Centrale PHENIX
Technical Session 9.2 / 6 March 2013
8
Dismantling of large components from PHENIX reactor
Preparation of the component
The component is delivered on the Handling Hall structural steelwork. To make
tilting easier, the shot is first removed by suction at the upper part using a vacuum
cleaner. The component is then tilted using the crane and then inserted into the
work airlock.
Removing the
shot
CEA MARCOULE – Centrale PHENIX
Tilt of the component
and insertion in the work
airlock
Technical Session 9.2 / 6 March 2013
9
Dismantling of large components from PHENIX reactor
Fitting out of a single part (1)
•
Argon cap cutting
The argon cap is cut up and removed from the DOTE body for characterization. The
VLL cut pieces are reinserted into the upper part.
CEA MARCOULE – Centrale PHENIX
Technical Session 9.2 / 6 March 2013
10
Dismantling of large components from PHENIX reactor
Fitting out of a single part (2)
• Preparation of injection ports
Injection ports and vents are made in the part to allow the injection of concrete
during its processing at ANDRA's CIRES storage centre. These openings are drilled
and screwed into the metal cover. New lifting gear as well as slings are set up. A
design note specifies the type of lifting gear and slings to be used as well as their
location on the part.
•
Painting
A special paint is applied to the single part to set any
trace of lip contamination and to prevent any
sweating.
CEA MARCOULE – Centrale PHENIX
Technical Session 9.2 / 6 March 2013
11
Dismantling of large components from PHENIX reactor
Deliver to the CIRES
Given the length of the unit room (over 6m), sending the 20-foot ISO container is
impossible and removal to the CIRES requires premium transportation. The
component is put in a frame.
Stowage off the component in a
frame
Transport of the component to
the CIRES
CEA MARCOULE – Centrale PHENIX
Technical Session 9.2 / 6 March 2013
12
Dismantling of large components from PHENIX reactor
Treatment Results
 Limiting the number of cuts (ALARA approach) and performing them with
the appropriate specific tools (wire saw).
 Optimizing the VLL dispatch (characterizing as accurately as possible).
 Giving preference to sending single parts.
 Optimizing volumes.
CEA MARCOULE – Centrale PHENIX
Technical Session 9.2 / 6 March 2013
13
Dismantling of large components from PHENIX reactor
To Conclude…
The treatment of the component in one single part can be considered only
if dose rate and contamination are compatible with VLL Waste’s
specifications.
However, we can retain that it is possible to deliver a large component
who stayed several years in the reactor to the CIRES.
CEA MARCOULE – Centrale PHENIX
Technical Session 9.2 / 6 March 2013
14
Dismantling of large components from PHENIX reactor
IAEA-CN-199/442
CEA MARCOULE :
ROUX Anne-Marie - DURAND Anne - FAURE André –
DOMINJON Franck
Département Exploitation des Installations de Marcoule (DEIM)
BLIN Pascal
Département des Projets d’Assainissement et de Démantèlement
(DPAD)
CERAT Didier
Département des Unités de Sécurité et Protection (DUSP)
CEA MARCOULE – Centrale PHENIX
Technical Session 9.2 / 6 March 2013
15