progress in am transmutation targets from efttra · general conclusion related to the use of spinel...
TRANSCRIPT
NEA P&T Exchange Meeting, Nimes, September 2006
D. Haas, A. Fernandez (JRC-ITU)D. Warin, J.-M. Bonnerot (CEA)C. Garzenne (EDF)W. Maschek (FZK) F. Scaffidi-Argentina (JRC-IE) F. Klaassen, R. Schram (NRG)
Progress in Am transmutation targets from EFTTRA
NEA P&T Exchange Meeting, Nimes, September 2006
The EFTTRA Collaboration: 15 years from 1992 to 2006
• Goal: transmutation of long-lived FP and MA
• Tc-99 and I- 129 irradiations performed and reported
• Inert matrices selection and irradiations in Phenix and HFR
• Pre-selection of MgAl2O3 for Am targets transmutation
• Irradiations (Am) in HFR: T4 and T4bis (2 burn-up levels)
• Results not conclusive > Selection of Zirconia (once-through scenario)
or MgO, Mo (multiple recycling scenario)
• Preparation of HELIOS irradiation in HFR
• Further developments
NEA P&T Exchange Meeting, Nimes, September 2006
EFTTRA: a 15-years successful collaboration
• Agreement on experimental programmes, seminars, publications
• Financing by the partners (case by case)
• Financial (partial) support through EC Framework Programmes:
• FP5 (EFTTRA T4)
• FP6 (EUROTRANS IP: HELIOS, BODEX)
NEA P&T Exchange Meeting, Nimes, September 2006
EFTTRA T4 and T4bis Objective
• MgAl2O3 spinel as IMF for once-through transmutation
• Development of Am spinel target fabrication
• First irradiation testing of Am spinel
• In-pile behaviour, transmutation demonstration
• Burn-up effect (two irradiation times)
NEA P&T Exchange Meeting, Nimes, September 2006
EFTTRA T4 and T4bis main conclusions
• Am spinel fabrication demonstrated, but improvements implemented
(matrix powder infiltration instead of green pellet infiltration)
• Irradiation successful (up to 650 days): no failure, good pellet structure
• Very high gas production (mainly He), low release (low T°)
• Very large pellet swelling (gas bubbles)
• Am-Spinel chemical instability: formation of AmAlO3
NEA P&T Exchange Meeting, Nimes, September 2006
EFTTRA-T4(bis) pellets: green pellet infiltration
Inhomogeneous Am distribution in spinelHELIOS: sol-gel beads infiltration
Solid-solution formation in the sintered pellet
MA-Laboratory
NEA P&T Exchange Meeting, Nimes, September 2006
EFTTRA T4 and T4bis main conclusions
• Am spinel fabrication demonstrated, but improvements implemented
(matrix powder infiltration instead of green pellet infiltration)
• Irradiation successful (up to 650 days): no failure, good pellet structure
• Very high gas production (mainly He), low release (low T°)
• Very large pellet swelling (gas bubbles)
• Swelling also due to n-damage
• Am-Spinel chemical instability: formation of AmAlO3
NEA P&T Exchange Meeting, Nimes, September 2006
0
50
100
150
200
250
300
350
400
0 100 200 300 400 500 600 700
Irradiation Time [full power days]
Pow
er D
ensi
ty [W
/cm
3]
9 0 %2 4 1 A m
2 3 8 P u
2 4 2 m A m
2 4 2 P u
1 0 %
8 3 %
1 7 %d e c a yd e c a yα -
2 4 2 A m2 4 2 A m
2 4 2 C m2 4 2 C m
2 3 9 P u2 3 9 P u
The two maxima are due to formation and fission of Am-242m and Pu-239, respectively. The EFTTRA T4 irradiation showed a similar power profile, but it did not reach the second maximum due to the shorter irradiation time.
Power density in the EFTTRA T4bis irradiationT4 Irradiation time
NEA P&T Exchange Meeting, Nimes, September 2006
50 µm
a)
50 µm
b)BOL EOL
As-fabricated T4 fuelIrradiated T4: 17% porosity
Irradiated T4bis: 25% porosity
AmAlO3
NEA P&T Exchange Meeting, Nimes, September 2006
T4bis Electron Probe Micro-Analysis
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
325 330 335 340 345 350 355 360 365 370 375
Wavelength (pm)
Mea
sure
d in
tens
ity (c
nts/
s)
Scan 0003-6-15
Uranium
Neptunium
Plutonium
Americium
Curium
Pu: 71 %
Cm: 19 % Am: 10 %
Composition of the 50% actinides remaining in the fuel
NEA P&T Exchange Meeting, Nimes, September 2006
6.6
6.65
6.7
6.75
6.8
6.85
45 55 65 75 85 95 105 115 125
Axial position (mm)
Out
er c
ladd
ing
diam
eter
(mm
)EFTTRA T4bis Profilometry and X-ray image
Cross section for investigation
NEA P&T Exchange Meeting, Nimes, September 2006
5 mm ≅ 320 μm 5 mm ≅ 1 μm
5 mm ≅ 320 μm 5 mm ≅ 2,5 μm
a)
b)
Profilometry and optical micrograph of an MgAl2O4 single crystal <110>
orientated irradiated with iodine ions of 72 MeV energy. The respective fluences
are 1015 for a) and 1017 ions/cm2 for b). The optical micrograph shows clearly
the irradiated area poping out from the original crystal surface.
NEA P&T Exchange Meeting, Nimes, September 2006
EFTTRA T4 and T4bis main conclusions
• Am spinel fabrication demonstrated, but improvements implemented
(matrix powder infiltration instead of green pellet infiltration)
• Irradiation successful (up to 600 days): no failure, good pellet structure
• Very high gas production (mainly He), low release (low T°)
• Very large pellet swelling (gas bubbles)
• Swelling also due to n-damage
• Am-Spinel chemical instability: formation of AmAlO3
NEA P&T Exchange Meeting, Nimes, September 2006
X-ray diffraction of EFTTRA-T4 fuel
spinel +
Am phase similar
to AmAlO3
spinel (crystalline!)
no Am phase
20 30 40 50 60 70 80 90 100
EFTTRA-T4 2006
cps
EFTTRA-T4 1996
2θ (°) Cu Kα
AmAlO3 (Keller 1965)
NEA P&T Exchange Meeting, Nimes, September 2006
EXAFS measurement
- annealing at 1600°C in Ar/H2
(as for production in 1996)
- about 60 mg Am-spinel powder in a
steel shielded Plexiglass cuvette
- measurement at INE Beamline at the
Ångströmquelle Karlsruhe, ANKA
EXAFS provides information
of local atomic structure:
- interatomic distance
- coordination number
- type of atom in coordination shells
- disorder
NEA P&T Exchange Meeting, Nimes, September 2006
Am LIII-edge EXAFS of aged and annealed EFTTRA-T4
10 years aged EFTTRA-T4 fuelshows no peaks corresponding to a periodic structure
0.0
0.5
1.0
0 2 4 6 8
0.0
0.5
1.0
Am3
2.36; 2.58; 2.88 Å
FT
Am2 5.30 Å
Am1 3.75 Å
Al 3.25 Å
Al N~1 3.28 Å
O1a-c
Data Fit amorphous AmAlO3
6.50 Å
R+Δ (Å)
Fit crystalline AmAlO3
Am L3-edge EXAFS of annealed EFTTRA-T4
fuel can be fitted with AmAlO3 structure
AmAlO3 is predominantin EFTTRA-T4 fuel
NEA P&T Exchange Meeting, Nimes, September 2006
General conclusion related to the use of spinel as IMF
• Conclusion based on T4+T4bis + other experiments in HFR and Phenix
• At low temperature, He retention leading to swelling
• At high temperature He release, but chemical instability
• Study started of a more stable IMF (once-through): Y-stabilised Zirconia
• Additional investigation of MgO and Mo for recycle strategies
• Need of irradiation experiments: HELIOS in HFR
NEA P&T Exchange Meeting, Nimes, September 2006
FUTURIX: irradiation test in Phénix of TRU-fuelsunder EFIT relevant conditions
BODEX: irradiation test in HFR to study the heliumbuildup and release from inert matrixes for IMF’s
HELIOS: irradiation test in HFR to study the in-pilebehaviour vs temperature of U-free Am targets
EUROTRANS IP (FP6) Irradiation Tests
NEA P&T Exchange Meeting, Nimes, September 2006
A B C D E F G H
1 + + + + + + + + +2 +3 +4 +5 + +6 +7 +8 +9 + + + + + + + + +
HELIOS
Fuel
Control rod
Be reflector
Irradiationpositions
HFR-Petten
NEA P&T Exchange Meeting, Nimes, September 2006
HELIOS test matrixPin Nr Composition Microstructure As-fabricated
density [g/cm3]Fuel
ManufacturerFuel Type
Remarks
241Am Putot
1 Am2Zr2O7+MgO 10-50 μm 0.7 0CEA
CerCer
2 (Am,Zr,Y)O2 Solidsolution
0.7 0JRC-ITU
Instrumentedwith
Central TC
3 (Am,Pu,Zr,Y)O2 Solidsolution
0.7 0.39 JRC-ITU Instrumentedwith
Central TC
4 (Zr,Am,Y)O2+Mo 60-120 μmmax 30 vol%
0.7 0 CerMet
5 (Pu,Am)O2+Mo 40-150 μmmax 30 vol%
0.3 1.2 JRC-ITU CerMet
JRC-ITU
NEA P&T Exchange Meeting, Nimes, September 2006
0
50
100
150
200
250
0 100 200 300 400 500 600
Irradiation Time (Days)
Fiss
ion
pow
er (W
/cm
)
Pufis 0.08 g/cm3 + 241Am 0.7g/cm3
Pufis 0.08 g/cm3
241Am 0.7 g/cm3
Power calculations
Fission of 242mAm
Fission of 239Pu
NEA P&T Exchange Meeting, Nimes, September 2006
Estimated temperatures
Pin CompositionPu-content
[g/cm3]
Am-content
[g/cm3]
Max Power
[W/cm3]
Linear Power
[W/cm]
Tcentral
[oC]
Calculated with power
[W/cm3]
1 Am2Zr2O7 + MgO 0 0.7 240 56 741 300
2 (Am,Zr,Y)O2 0 0.7 170 40 811 230
3 (Pu,Am,Zr,Y)O2 0.39 0.7 740 170 1439 787
4 (Am,Zr,Y)O2 + Mo 0 0.7 250 58 687 300
5 (Pu,Am)O2 + Mo 1.2 0.3 1600 370 1477 2020
Onset of He release: ≈ about 550 oCComplete He release: ≈ about 1350 oC
NEA P&T Exchange Meeting, Nimes, September 2006Sintered density > 90%TD
(Am,Zr,Y)O2 pre-fabrication tests
NEA P&T Exchange Meeting, Nimes, September 2006
• HELIOS irradiation shall start in 2007 in the HFR and last for about 1 year (i.e. 10 HFR cycles)
• Fuel production and hardware procurement & manufacturingunderway
• Predicted temperatures in the fuels are acceptable (slightly lower than aimed)
• Destructive PIE’s results shall be available in 2009
HELIOS Status
NEA P&T Exchange Meeting, Nimes, September 2006
Future EFTTRA plans
• Complete HELIOS experiment within EUROTRANS IP
• Integrate the results within other experiments: BODEX
• Demonstrate the high Am transmutation capability of Zirconia IMF
with a 5-years irradiation in HFR: HELIOSbis (not decided – funding
dependent
• Looking at the feasibility of Cm transmutation in once-through mode