Tritium fuel cycle and self-sufficiency - R&D for DEMO and ... Meeting...R&D for DEMO and required...
Transcript of Tritium fuel cycle and self-sufficiency - R&D for DEMO and ... Meeting...R&D for DEMO and required...
Tritium fuel cycle and self-sufficiency - R&D for DEMO and required extrapolations beyond ITER
Christian Day,
Project Leader of the EUROfusion TFV (Tritium-Matter Injection-Vacuum) Project
15-18 November 2016, KIT
Introduction
EU DEMO fuel cycle single technology developments
Fuel cycle integration aspects
Conclusions
Outline
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 2
EU DEMO Power Plant Definition
DEMO Mission Statement:
“The DEMO power plant has to be a representative fusion power station in terms of predictable power production, fuel cycle self-sufficiency and plant performance thereby allowing an extrapolable assessment of the economic viability, safe operation as well as environmental sustainability for future commercial fusion power plants (FPP).”
Hence, DEMO has to:
Be conceived as single step between ITER and a commercial FPP
Produce net electricity (several 100 MWe), safely and reliably
Be tritium self-sufficient and start up another reactor
Demonstrate all technologies for the construction of a commercial FPP Have a representative (extrapolable)
performance:
Lifetime
Cost
Availability and net efficiency
Waste
..Hence, DEMO is not a large ITER, but different.
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 3
G. Federici, FED 2016.
Tritium self sufficiency
Demonstration of tritium self-sufficiency is a central element in the fusion roadmap. To demonstrate tritium self-sufficiency successfully, we need to be successful in three aspects at the same time:
TBR
BUF
FCT
Good tritium breeding ratio Breeding blanket / Outer fuel Cycle
High burn-up fraction Particle exhaust at divertor
Efficient fuel cycle technologies to reduce inventory
We need to have sufficient tritium to start and then to provide:
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 4
In a simplistic way, one may think to just scale up the ITER fuel cycle.
What we found was that this will end in a number of issues:
…operational complexity, facility size (cost), …
but most of all:
The tritium inventory may act as a SHOWSTOPPER for DEMO:
…in terms of the start-up inventory (may be too high)
…in terms of the regulatory limit (may not be achievable)
…in terms of excessive cycle times and correspondingly too large inertia of the system (tritium plant becoming a very very large chemical plant)
DEMO is a (pre-commercial) power plant, not a physics device
designed for experimental flexibility
DEMO will be designed around one single operational target point
(within an uncertainty margin due to control safety, stability and to meet unknowns, designed for a metal wall right from the start)….
Central DEMO fuel cycle challenge – Inventory reduction
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 5
Generic functional fuel cycle scheme
Torus
Tritium Recovery
Bla
nke
t
Isotope Separation
Storage & Delivery
Water Detritiation
D, T DT
Q2 Q2
D,T
Water, He
Impurities
Water, He
Impurities
Q2
Tritium Extraction
Tritium Accountancy
Q2
Helium / Water
T H,(T)
Coolant Purification
Primary Pumping
Rough Pumping
Fuelling & Plasma Control
Q = H,D,T
Tokamak Tritium
Plant
DT
Inner part
Outer part
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 6
B. Bornschein, FED 2013.
Generic functional fuel cycle scheme (2)
M. Abdou, FED 2015.
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 7
Fuel cycle implementation CFETR
C.A. Chen, Technical Exchange Meeting, Jan 2016
ITER-style Cryopumps
GC, CD, TCAP
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 8
Design driver to advance the fuel cycle architecture
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 9
M. Abdou, FED 2015.
Target is - to reduce processing times - to increase fuelling efficiency - to increase burn-up fraction
Introduction
EU DEMO fuel cycle single technology developments
Fuel cycle integration aspects
Conclusions
Outline
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 10
Innovative new fuel cycle concept - FBS
, PEG
PEG
PEG,
Chr. Day, FED 2016.
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 11
Derived with a rigorous systems engineering approach
Separation enables DIRECT INTERNAL RECYCLING
Innovative new fuel cycle concept - FBS
, PEG
+ Bypass to the Tokamak to allow easy ramp-up during dwell ´always´steady state
RESIDENCE TIMES
TRITIUM CONTENT
MINIMISED INVENTORY
PEG
PEG,
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 12
Rank Technology
1st Pd-Alloy Permeator
2nd Cryogenic Adsorption on
Molecular Sieve
3rd Getter Bed
4th Cryogenic Freezing
Impurity removal (85%)
Rank Technology
1st Membrane Reactor
(catalyst + permeator)
2nd High Temperature Electrolysis
3rd Catalytic Oxidation
Impurity processing (80%)
Rank Technology
1st Thermal cycling absorption process
2nd Plasma Separation Process
3rd Cryo-distillation
4th Gas chromatography
5th Electromagnetic isotope separation
6th Quantum Sieving
7th Pressure Swing Adsorption
8th Laser Isotope Separation
9th Gaseous Diffusion
10th Molecular Laser Isotope Separation
11th Kinetic Isotope Effects
12th Centrifugation
Primary loop protium removal and isotope sep. (75%)
Isotope re-balancing (75%) Rank Technology
1st Plasma Separation Process
2nd Thermal cycling absorption
process
3rd Cryo-distillation
4th Quantum Sieving
5th Laser Isotope Separation
6th Gas chromatography
7th Pressure Swing Adsorption
8th Electromagnetic isotope
separation
9th Gaseous Diffusion
10th Kinetic Isotope Effects
11th Molecular laser isotope
separation
12th Centrifugation
Rank Technology
1st Magnesium hydride catalysed ball
milled
2nd Depleted uranium
3rd Zirconium cobalt
4th Super diamond nanotubes
5th Ammonia borane SBA 15 (mesoporous
silica scaffold)
6th Sodium alanate
7th Lithium Borohydride
8th Activated carbon
9th MOF- 5 (metal organic frameworks)
10th Magnesium Borohydride
Storage (alt. U-Bed) (63%)
Rank Technology
1st Getter Beds
2nd Molecular Sieve Bed
3rd Cryogenic Molecular Sieve Bed
4th Pd-Ag Membrane
5th Water Gas Shift Reaction
6th Cold Trap
Rank Technology
1st Combined electrolysis and catalytic
exchange
2nd Liquid Phase catalytic exchange
3rd Direct electrolysis
4th Vapor phase catalytic exchange
5th Water distillation
Tritium recovery from water coolant (67%)
From the ranking we derive which R&D has to be done with highest priority
Technology ranking results tritium
Tritium recovery from helium coolant (70%)
Rank Technology
1st BIXS and scintillation depending on
detection case (13 cases altogether)
Accountancy (75%) Success of 30 year fusion research
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 13
Exhaust Processing R&D – Technology similar to ITER, but operation conditions different: - Significantly higher PEG concentration reduces hydrogen partial pressure - PEG may be activated - Scaling towards higher throughputs unclear
Protium removal and isotope re-balancing R&D – TCAP is not used at ITER but has been advanced mainly in the defense programmes (US, F, China). - Own complementary work may be needed to get full understanding - Scaling towards DEMO throughputs and resulting complexity must be assessed.
Helium coolant detritiation R&D – Need for performance improvement of existing technology in view of the huge flowrates involved.
Water coolant detritiation R&D - Similar technology as for ITER and also applied in heavy water reactors. However, scaling to DEMO seems to have a significant impact on plant cost.
Main R&D headlines tritium
Dynamic control of the loops R&D – Due to the continuous operation of the fuel cycle avoiding the use of intermediate storage wherever possible, gas distribution, control and tritium accountancy become more important.
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 14
New requirement: PEG
A variety of plasma enhancement gases are needed for DEMO: For confinement recovery at a metal wall, for radiative seeding, … Different candidates have different activation progeny.
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 15
R. Walker, SOFT 2016
Translation into resource loaded R&D programmes
Considering the existing limitation of resources in the TFV project. At any time in the project the choice of projects to be funded can be re-adjusted immediately.
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 16
Technology review outcome BB interface
TRITIUM EXTRACTION from the breeder has to convert the breeder outlet (tritiated water, Q2, carrier species) to an input stream to the tritium plant.
60%
60%
50%
Rank Technology
1st Cold trap and adsorption
columns
2nd Continuous catalytic
membrane reactor
3rd Getter bed
Solid Breeder (HCPB)
Rank Technology
1st Permeator against vacuum
2nd Vacuum sieve tray
3rd Gas-liquid contactor
Liquid Breeder (HCLL, WCLL, DCLL)
87% 75% 50%
Cryo-batch concept retained as reference at the moment
membrane
vacuum+ tritium
PbLi in
PbLi out
c1
c2
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 17
Technology review outcome matter injection (1)
Fuelling (ELM pacing ?)
Rank Technology
1st Classical pellet injection
2nd Microwave, laser, railgun
3rd Gas puffing, supersonic jets
4th Compact tori
5th Unmagnetized plasma jet
75% < 50% (with ´zeros´)
For gas injection (PEG, gas puffing, incl. massive gas injection) we rely much on ITER technology.
Matter injection has to provide the function of FUELLING and PLASMA CONTROL.
For core fuelling, we go for pellet injection, however have to advance this beyond the ITER operational window.
Can be fueled from the LFS
Large ratio Pellet mass / Plasma mass Large penetration deposition in the core Moderate plasma
pressure limited drift
Small ratio Pellet mass / Plasma mass Shallow penetration deposition at the edge High plasma pressure large drift
HFS injection mandatory
B. Pegourie, 2016
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 18
Technology review outcome matter injection (2)
Operational Parameters core ne = 0.9 x 1020 m-3 > nGw
Fusion power
Particle deposition
profile Pellet physics
Pellet parameter
Pellet technology
R&D pellet physics – Develop a self-consistent physics model that translates plasma parameters in engineering requirements (workflow).
R&D pellet guiding tubes – We do have a need to increase launch speed (over what ITER requires) and effective guiding tube systems.
R&D technology demonstration – An EU pellet test bed is needed to develop all engineering features of the DEMO pellet injector: rate, mass, speed
P.T. Lang, FED 2015
B. Plöckl, FED 2015
Curved guide tube ~ 1 km/s
Free flight option (double stage gas gun) ~ 3 km/s
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 19
Technology review outcome matter injection (3)
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 20
P.T. Lang, 2015.
The (unwanted) contribution of the pellet injection system to the machine throughput (SOL, Vacuum system) is essential.
Nowadays technology:
launch
≈35%....65%
(given by losses
In the guiding system
and SOL
curvature and speed,
deposition depth)
Technology review outcome vacuum (1)
PRIMARY PUMPING has to provide very high pumping speeds, but – different to conventional applications - due to large flowrates, not due to low pressures.
70% 50% 30%
R&D diffusion pump – Develop vapor diffusion pumps for high throughputs and pressures by integration of additional jet stages.
Rank Technology
1st Vapor diffusion pump (continuous)
2nd Metal foil pump (continuous)
3rd Cryocondensation
4th Cryosorption
5th Cascaded cryosorption
6th Continuous cryosorption
7th Warm turbopump
8th Cold turbopump
Primary pumping
R&D metal foil pump for separation and Direct Internal recycling – The metal foil pump has never gone into commercial applications. Develop technology from fundamental physics.
R&D cryopump – Develop multi-stage cryopumps which – to some extent – would allow to implement a separation capability into cryopumping fall-back solution (for risk mitigation).
R&D topic divertor integration – Contribute to an integrated design of the DEMO divertor by physics-based modeling of the particle exhaust to extract the influence of pumping speed (workflow) Chr. Day, FED 2014
Chr. Day, IEEE Trans. Plasma Science 2014.
Pump with separation function
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 21
Technology review outcome vacuum (2)
The most challenging requirement for mechanical ROUGH PUMPING for DEMO is the required tritium compatibility at large throughputs (excluding most conventional solutions due to rotary feedhrough issues).
90% 70% 40%
R&D ring pump – Integrate a tritium compatible liquid metal (mercury) into a liquid ring pump.
Rank Technology
1st Liquid ring pump
2nd Roots pump
3rd Scroll pump
4th Rotary vane pump
5th Screw pump
6th Diaphragm pump
Rough pumping
K. Battes, FED 2015 .
R&D wall outgassing – To respond to one of the high-level requirements: Integrated modelling of DEMO pump-down (dwell phase).
T. Giegerich, Fus. Sci. Technol. 2015
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 22
Technology choice vacuum (1)
Metal foil pumping is a central part of the DIR concept
Allows continuous gas separation under vacuum, close to the machine
Works only as a pump for atomic hydrogen isotopes
Thermal or non-thermal atomizers for generating atomic hydrogen available
Experimental investigations currently ongoing in a small scale test set-up
Modelling method required for scaling
Classical permeation ~ (p1
½-p2½)
Superpermeation ~ flux1
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 23
HERMES test facility @ KIT
B. Peters, SOFT 2016.
Technology choice vacuum (2)
Linear vapour diffusion pumps as simple, reliable and tritium- compatible primary pumps
Customized design for optimal pumping
Using mercury as operating fluid
Liquid ring pumps with mercury as operating fluid
A full scale tritium-compatible pump will be built and utilized at JET DT operation (2018).
THESEUS test facility @ KIT
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 24
Demonstration in JET DT campaign in 2018.
T. Giegerich, SOFT 2016. T. Giegerich, FED 2016.
KALPUREX©:
Karlsruhe liquid
metal based
pumping process for
reactor exhaust gases
Direct Internal Recycling Process
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 25
T. Giegerich, FED 2014 .
DEMO fuel cycle chosen technologies
, PEG
PEG
Pellet injection
Metal foil pumping
Mercury based vacuum pumping
Membrane reactor
Water formation
CECE
CD
U-bed
TCAP
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 26
Dynamic control
Current DEMO fuel cycle architecture
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 27
R. Lawless, TRITIUM 2016.
Introduction
EU DEMO fuel cycle single technology developments
Fuel cycle integration aspects
Conclusions
Outline
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 28
Tritium migration issues ask for joint assessments
T production
~ 360 g/d
T releases
< 0.002 g/d
D. Demange, 2012
The tritium extraction from the blankets is an interface that sets how the tritium handling load is shared between the blankets and the tritium plant. Similarly is teh tritium recoveyr from teh breeder coolant. It consequentially has to be assessed by all stakeholders (system owners) together.
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 29
Example CPS interfaces
The amount of tritium permeation from BB to Coolant loop is necessary to define the αCPS (fraction of coolant treated inside CPS).
A correct assessment of the tritium permeation can derive only from an integrated approach.
BB Coolant
CPS
PHTS & BOP
• ηTES
• Anti-permeation
barriers (PRF)
• Oxide layers
• Anti-permeation
barriers (PRF)
• Oxide layers
• ηCPS
• αCPS
T permeation
• Cooling tubes area
• Cooling tubes
thickness
• Tritium inventory in the cooling channels
• Tritium inventory in the coolant (HT and HTO)
T permeation
BB Designers T simulation PHTS & BOP Designers Materials CPS Designers
Safety
• T release
into env.
Fraction of coolant to be treated in CPS
CPS efficiency and coolant chemistry
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 30
CPS requirements (1)
Input data
• Allawable T conc. in the
coolant (c0);
• Tritium permeation from BB
to coolant (FT,p);
• CPS efficiency (ηCPS);
• Permeation Reduction
Factor (PRF)
𝐹𝑐0 = 𝐹𝑐𝑖 +𝐹𝑇,𝑝
𝑃𝑅𝐹𝐵𝐵
𝜂𝐶𝑃𝑆 = 𝑐0 − 𝑐𝑢𝑐0
𝐹𝑐𝑖 = (𝐹 − 𝛼𝐹)𝑐0 + 𝛼𝐹𝑐𝑢
1-2
3-4
2-1
𝛼 =
𝐹𝑇,𝑝𝑃𝑅𝐹𝐵𝐵
𝐹𝑐0𝜂𝐶𝑃𝑆
The calculations have been
performed considering
BB SG CPS
F, c0
F, c0
αF, c0 αF, cu
F, ci
FT, p
1
2
3 4 PRF
Coolant fraction to be
treated inside CPS
• c0= 5ppb;
• FT,p in Case#1 and #2
• ηCPS equal to 0.9 and 0.95
• PRF equal to 1, 10 and 100
Parametric Analysis
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 31
A. Santucci, SOFT 2016
Amount of coolant to be treated inside the CPS for different CPS efficiencies and PRF values: HCPB
ηCPS PRFBB αCPS αCPS × F,
kg s-1
0.9
1 0.00083333 2.000
10 0.00008333 0.200
100 0.00000833 0.020
0.95
1 0.00078947 1.894737
10 0.00007895 0.189474
100 0.00000789 0.018947
Amount of coolant to be treated inside the CPS for different CPS efficiencies and PRF values: WCLL
ηCPS PRFBB αCPS αCPS × F,
kg s-1
0.9
1 0.00787037 37.77777
10 0.00078704 3.777778
100 0.00007870 0.377778
0.95
1 0.00745614 35.78947
10 0.00074561 3.578947
100 0.00007456 0.357895
• In ITER // HCPB-TBM: 0.00372 kg s-1
G. Piazza, F4E
• In ITER // entire WDS: 0.0166 kg s-1)
CPS requirements (2)
A. Ciampichetti, FED 2010
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 32
Philosophy for Implementation of R&D work –
Complement to experiments
A unified fuel cycle simulator is being developed, which integrates the individual system blocks. This will be based on Aspen Custom Modeller, an equation oriented solver platform for dynamic process simulation, we work to do this in collaboration with ITER.
A predictive model is being elaborated for each system block.
The model is tested and deployed if working, or iteratively improved.
The model (and at a later stage the complete simulator) is a perfect tool to explore design space and conduct parametric variations of influential parameters.
Open, commercially available and fully documented chemical engineering plant software, no in-house codes
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 33
Fuel Cycle Simulator based on comm. software platform
Numerical implementation cross-check vs ABDOU, 1985
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 34
Philosophy for model preparation
The model can be on various levels… fundamental equations (such as diff. balance and conservation equations),
applicable difference equations (such as HTU, NTU, stage concepts,…),
correlation of representative experiments, zeroth order approaches.
…requiring largely different computational efforts…
…and providing largely different understanding for further system optimization.
Once the model is there, it has to be tested. This requires to have a representative test case, which can be literature data or experiments.
Often, we will find that we miss input information. Then, one has to set up additional side-experiments to generate such input information (thermodynamic properties, transport coefficients, kinetics,...) needed to run the main model so that the results are quantitatively representative.
This is the only accepted driver for experiments (not scientific curiosity…), and even this only if it is known that the side-experiment result has a high impact on the model result.
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 35
2 4 6 8 10 12 14 16
R [m]
− 10
− 8
− 4
− 2
0
2
4
6
8
10
Z[m
]
Pellet injection engineering
Detached Divertor modeling
Core transport model and burn control
Sub-divertor neutral flow and recycling modelling
Pellet deposition and ablation modelling
Particle exhaust und pumping engineering
SOL loads to exhaust system
Integrated Physics model of the (physics relevant) part of
the fuel cycle
Holistic approach: Physics-Engineering Integration is a must.
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 36
DT machine gas throughput
For steady state DEMO operation fuel replenishment due to DT burn is rather small (~2.6 Pa m3/s) and corresponds to the low burn-up fraction (high T inventory)
DT particle throughput due to plasma outflow strongly depends on the tungsten wall outgassing and pumping . Can be roughly estimated as 40 Pa m3/ s and is being fuelled by HFS pellets.
DT replenishment due to He removal in DEMO will very much depend on He enrichment factor in divertor. For limited He concentration in core ≤ 5% one needs to inject about 180 Pa m3/s for enrichment factor value higher than 3%.
LFS GP about 75 Pa m3/s will required for generation of sufficient neutral pressure and low power loading in the divertor (detachment).
Pellet-induced ELMs remove DT particles and are replenished by injected HFS or LFS pellets ~19 Pa m3/s .
N=1x1021/s = molecular gas throughput of 1.7 Pa∙m³/s (referenced to T=273.15 K)
This sums up to minimum 300 Pam³/s DT + ELM pacing gas load + PEG + SOL losses (mainly from pellet injection pumping) Burn-up fraction of maximum 1 %.
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 37
DT machine gas throughput with high burn-up fraction
In this case, the DT burn-up fraction can be as much as 10 %, and the DT machine throughput is significantly reduced.
σvnταβ4
σvnταβf
E
E
fuel
burnb
MeVTσvnτE 5.3/)0(12
With (via Lawson-criterion):
and T(0)=26 keV (PROCESS)
for „clean“ wall b→1, ab ~ 1/3÷1/5 , fb ~ 0.5%,
fuel~ 490 Pa-m3/s
for fburn ≥ 10%, (ab ~ 2) tp* ~ 6÷10∙tp →
fuel = burn / fb ≤ 26 Pa-m3/s
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 38
Concept to increase ß:
Continuous Exhaust gas re-injection to artificially increase recycling R
H. Zohm, 2015.
Compression due to re-injection He enrichment due to atomic physics
p
pumpburnfuel
VnVv
n
t
4
2
Epp tabtbt
Particle exhaust modelling
Collisionless, x=0.3 Collisional, x=0.3 Collisional, x=1.0
Pressure maps for two
extreme virtual cases:
With and without dome
Calculated with the Direct
Simulation Monte Carlo
(DSMC) code DIVGAS
developed at KIT.
The neutral flow field in the sub-divertor which results from the plasma boundary, the exchange of particles via refluxes, and the vacuum pump capture coefficient, plays a role for the high density scenarios foreseen in DEMO. The EU DEMO divertor development for the first time will be an integrated effort, joining, physicists, material engineers and vacuum engineers. Particle transport to quantify fb is possible.
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 39
S. Varoutis, 2016.
Summary and Conclusions
A comprehensive programme is being implemented to advance the
DEMO fuel cycle towards a conceptual design in the next 10 years.
This enterprise is following a system engineering approach to make all
decisions fully traceable and more easily adaptable, if requirements
change.
We propose a new inner fuel cycle architecture to be best fit-to-
purpose, driven by the need to minimise inventory and increase burn-
up fraction, characterized by 3+1 loops.
It is essential to implement an integrated and holistic view on the fuel
cycle.
Chr. Day | IAEA DEMO WS, Karlsruhe | Nov 2016 | Page 40