Opportunities for research
on material compatibility
and tritium behavior
at the STAR laboratory
Pattrick Calderoni
Fusion Safety Program
Idaho National Laboratory, USA
HAPL Program Meeting
GA San Diego
8-9 August 2006
Fusion Safety Program
Objectives
Introduce the INL Safety and Tritium Applied Research facilities
and research capabilities in the areas of compatibility and
tritium behavior for fusion chamber and blanket materials
Summarize recent and ongoing activities at
INL that are relevant to the HAPL program
Present a preliminary plan to integrate HAPL chamber and
blanket R&D with the current and planned STAR activities
Collect directives, comments, suggestions, impressions, desires, …
on technical and programmatic aspects to consolidate the
preliminary plan into an R&D proposal
Slide 1
Fusion Safety Program
STAR Mission and Research
•
Provide laboratory infrastructure to study tritium science and technology
issues associated with the development of safe and environmentally friendly
fusion energy
•
Designated a National User Facility
•
Research thrust areas
– Plasma-material interactions of PFC materials with energetic tritium and
deuterium ions
– Fusion safety: chemical reactivity, activation product mobilization and
dust/debris characterization for PFC materials; tritium behavior in fusion
systems (in-vessel source term)
– Molten salts and fusion liquids for tritium breeder and coolant applications
– Fission reactor tritium production permeation issues; AGR fuel tritium
retention and release studies
– Tritium plant and fuel cycle issues for MFE and IFE
Slide 2
Fusion Safety Program
STAR Floor-plan Layout
Glovebox
TCS
Tritium
SAS
Chemical reactivity
experiment
Tritium
Stack monitor
D ion implantation
experiment
Glovebox exhaust
manifold
Tritium Plasma Exp
Flibe-tritium
experiment
Flibe-corrosion
experiment
Flibe preparation
purification & testing
Flibe Salt
2Lif-BeF2
15,000 Ci tritium limit
15,000 Ci tritium limit
Segregation
of operations
Segregation
of operations/ventilation
Once-through
Gloveboxesroom
andventilation
hoods
Gloveboxes and hoods
Tritium cleanup system
Tritium cleanup system (TCS)
Once-through
room
Tritium
storage and
assayventilation
system (SAS)
Slide 3
Fusion Safety Program
Key systems in STAR
Molten Salt Tritium
Behavior Experiment
Tritium Plasma Experiment
and Enclosure
Tritium Cleanup System
Molten Salt Preparation,
Purification, and REDOX
Experiments
Tritium
Storage and
Assay
System
Steam and air
chemical reactivity
test apparatus
Slide 4
Fusion Safety Program
STAR is Ready for Operation of Tritium Experiments
•
Useable tritium inventory currently 1300 Ci
–
–
–
300 Ci in equimolar H2:D2:T2 calibration
standard
1000 Ci T2 available for experiments
shipments from SRS limited to 1000 Ci with
standard TYPE-A container
• Molten Salt Tritium Permeation Experiment:
–
–
–
100 to 300 Ci transferred as D2/T2 in vessel loaded with SAS
diagnostics to include QMS, gas chromatograph, on-line ion chamber,
and catalytic recovery
effluent will exhaust via facility stack
• TPE Tritium Experiments:
–
–
700 to 900 Ci transferred as T2 in vessel loaded with SAS
local U-Bed capture in TPE; effluent routed to TCS for complete cleanup
Slide 5
Fusion Safety Program
Molten salts R&D
Redox, the control of fluorine potential
D. Olander, letter to the editors of J Nuc Mat (02)
•
Experiments at Kyoto and Tokyo Un with fast
neutrons (Moriyama, Oishi 97/89, Suzuki
98/00) showed that tritium is generated in
Flibe as TF without the addition of H2
•
TF reacts with structural materials
generating high solubility fluorides
•
Need to control fluorine potential to minimize
corrosion
•
Of the three options (purge H2/HF mixtures,
add metal element, add ternary salt) the use
of metallic Be is best for fusion applications
when considering the complexity of ternary
salts chemistry and T permeation issues
0
CeF3/CeF4
NiF2
-RTlnpF2 (kJ/mole)
The redox condition of molten fluoride salts is
quantitatively described by the fluorine potential.
The fluorine potential, however applied, controls
the equilibrium concentration of structural
materials dissolved in flibe.
Fluoride Potential
-200
H2/HF=10
FeF2
-400
H2/HF =
20/low
pressure H2
-600
CrF2
Si2F6
-800
MnF2
AlF3
-1000
BeF2
-1200
LiF
450
550
650
750
Temperature (°C)
Slide 6
Fusion Safety Program
Molten salts R&D: redox experiments
Be rod
Measure HF
in the gas
phase as a
signature of
REDOX
potential
Inject HF
•
On-line detection of HF in the
gas with titrator and mass
spectrometer allows dynamic
time dependent analysis
•
Controlled parameters:
HF/H2 concentration,
temperature, Be exposure time
into the Flibe
Hydrofluorination is first used to purify the salt from oxides and metal impurities:
M + 2HF <--> MF2 + H2
BeO + 2HF = BeF2 + H2O
When equilibrium is reached (pure salt) a metallic Be rod is inserted in the salt
for a specified time
Available Be reacts with HF until initial conditions are restored
Slide 7
Fusion Safety Program
Flibe purification facilities
Hydro-fluorination approach
•
Control instruments
& He-HF gas cabinet
Bubble H2/HF/He thru melt (530ºC)
Chemical Analysis of Flibe
•
On components
•
Pre and post purification
•
Techniques:
Metals: ICP-AES, ICP-MS, acid
dissolution
C, N, O: LECO
Pot/heater assembly
Titration cell
Gas manifolds
HF traps
O
(ppm)
C
(ppm)
N
(ppm)
Fe
(ppm)
Ni
(ppm)
Cr
(ppm)
BeF2
5700
<20
58
295
20
18
LiF
60
<20
78
100
30
4
Flibe
560
10
32
260
15
16
Processed
Flibe
Slide 8
Fusion Safety Program
Redox experiments: analysis and complexities
1400
Simple model
1200
HF input (1000 ppm) >
dissolution rate
1000
Exposure time does not influence
recovery (only HF concentration)
but
Solubility of Be0 from integration
of titrator data higher than MSRE
HF concentration (ppm)
Be dissolves as Be0
20 min
30 min
10 min
60 min
800
REDOX-4
REDOX-5
REDOX-6
REDOX-7
REDOX-10
600
400
200
0
Complex model
0
10
20
30
40
50
60
70
time (hr)
Be dissolves as Be0 and enters the salt by galvanic mechanism as ionic Be2+
(demonstrated by recent tests with insulated Be rod)
Initial ionic migration > HF input and Be deposits on Ni crucible
Exposure time does not influence recovery (only HF concentration and available
deposition surface for ions)
Currently measuring ionic migration by electrochemical analysis to decouple processes
Slide 9
Fusion Safety Program
Ferritic steel corrosion tests
He
He+H2+HF
TC
He
He
He
He+H2+HF
FSCT #1 and #2 concluded
Analysis of results ongoing at INL and in Japan - stay tuned for Jupiter II final reports
Slide 10
Fusion Safety Program
Tritium permeation experiments
Experiments are designed to investigate tritium
behavior in flibe / Ni systems with Redox control
Previous experiments in Japan under irradiation
complicated by oxide layer formation
Chamber designed and constructed in Japan,
tested with H2 to verify negligible convection effects
Gas supply system, glove-box, instruments
and control already tested with previous D2
permeation experiment
6.35 
30
30
6.35 
6.35 
lid ss316
12.7
6.35
108
20
150
1
12.7
110
6.35
2
6.35
ss316
Ni
160
2
240
ss316
Ni
100
9.52
9.52
60.3
Ni
2
4
4
10
2
2.8
Ni
114
4
95
Slide 11
Fusion Safety Program
Tritium permeation experiments
•
Tritium provided in
pressurized vessel
containing D2/T2 mixture
•
Glovebox setup to contain
potential leaks, connected
with tritium clean-up system
•
GC column coupled with
ionization chamber has
been tested with tritium
•
Develop DF/TF generator
to compare with T2
permeation results
•
Builds on success of TMAP
modeling with D2
permeation experiment
•
1-D axial model with sink
terms to simulate radial loss
Vacuum
pump
Pressure gauge
HF trap
Flow meter
exhaust
Flow meter
Gas chromatograph
+ ionization chamber
And QMS
Flow meter
Cap
High temperature salt
Flibe
Ar
D2
Ni
T2
Be insertion
Slide 12
Fusion Safety Program
Flibe and Sn-Li alloy mobilization
studies for blanket safety analysis
Objectives: measure the vaporization and mobilization properties of molten Sn25at%Li
(in argon) and flibe (in argon, air and air+water vapor) from 600 to 1400K
Approach: use a mass spectrometer equipped with a Knudsen effusion source to
measure the partial pressure of condensable vapors. Partial pressures are
derived from spectral line intensities after calibration with Li metal. Mobilized
deposits were analyzed by ICP-AES.
Slide 13
Fusion Safety Program
Pb-Bi corrosion test for Fast Breeder Reactor
QuickTime™ and a
TIFF (LZW) decompressor
are needed to see this picture.
Slide 14
Fusion Safety Program
Corrosion mechanism in liquid metals
QuickTime™ and a
TIFF (LZW) decompressor
are needed to see this picture.
Slide 15
Fusion Safety Program
Corrosion mechanism in liquid metals
QuickTime™ and a
TIFF (LZW) decompressor
are needed to see this picture.
Slide 16
Fusion Safety Program
Pb-Bi corrosion test for Fast Breeder Reactor
QuickTime™ and a
TIFF (LZW) decompressor
are needed to see this picture.
Slide 17
Fusion Safety Program
Integration of HAPL chamber and blanket R&D
with current and planned STAR activities
A gradual integration would be beneficial to:
• minimize budget for research activities and facilities
• allow maximum flexibility to accommodate design changes and
leverage on other R&D programs with common objectives (ITERTBM, Z-IFE, GNEP, etc)
• incorporate INL Fusion Safety Program expertise in the HAPL
chamber and blanket design and analysis
• start a collaborative program that could lead to a full utilization of
the STAR laboratory capabilities, including applied research on
tritium behavior in blanket materials, tritium inventory assessment
and blanket safety analysis
Slide 18
Fusion Safety Program
Integration of HAPL chamber and blanket R&D
with current and planned STAR activities
Task 1
SiC / flibe material compatibility tests and
Redox control assessment and optimization
Task 1
FY 1
FY2
FY3
Static compatibility test: SiC / flibe
Design and construction
Operation
Analysis
Redox and corrosion tests: SiC / flibe
Design and construction
Operation
Analysis
Flibe batch preparation
Requires minimal modification of available STAR facilities for T < 700C
Utilizes available state-of-the-art analytical techniques, including electrochemical measurements, and
extensive expertise of scientific and technical personnel
Allows comparison with static compatibility tests of Pb-17Li for TBM program ongoing at ORNL (B. Pint)
Slide 19
Fusion Safety Program
Integration of HAPL chamber and blanket R&D
with current and planned STAR activities
SiC / Pb-17Li material compatibility tests and
corrosion control assessment and optimization
Task 2
Task 1
FY 1
FY2
FY3
Prepare and purify Pb-17Li
Design and construction
Operation
Analysis
Corrosion control tests: SiC / Pb-17Li
Design and construction
Operation
Analysis
Requires re-assembly and modification of Pb-Bi alloy experiment
Utilizes available state-of-the-art analytical techniques and expertise of scientific and technical personnel
Start could wait until completion of Task 1 to leverage on other R&D and continued analysis and design of
HAPL chamber and blanket system (ie, choice of coolant)
Slide 20
Fusion Safety Program
Integration of HAPL chamber and blanket R&D
with current and planned STAR activities
Task 3
Task 1
T permeation experiments in SiC / flibe
systems and SiC / Pb-17Li systems
FY 1
FY2
FY3
T perm test: SiC / flibe
Design and construction
Operation
Analysis
Requires modification of planned T permeation experiments in flibe / Ni systems for T < 700 C
Utilizes available state-of-the-art analytical techniques and expertise of scientific and technical personnel
Start would depend on Task 1 and 2 results, as well as continued HAPL blanket analysis and design (ie,
coolant material choice)
If comparison of material properties is needed research activities for flibe and Pb-17Li could be carried
out in parallel depending on research budget and personnel availability
Slide 21
Opportunities for research
on material compatibility
and tritium behavior
at the STAR laboratory
Pattrick Calderoni
Fusion Safety Program
Idaho National Laboratory, USA
HAPL Program Meeting
GA San Diego
8-9 August 2006