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M. Enoeda, Y. Nomoto, S. Suzuki, D. Tsuru, K. Ezato, T. Hirose, H. Tanigawa, H. Nishi and M. Akiba

Blanket Development GroupFusion Research and Development Directorate

Japan Atomic Energy Agency (JAEA)

Current Status of Design of Solid Breeder Test Blanket Module of Japan

14th International Workshop on CERAMIC BREEDER BLANKET INTERACTIONS6–8 Sept. 2006, Petten, The Netherland

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Contents

1. Design overview of Japan Solid Breeder TBMs2. Possible neutronics diagnostics of TBMs3. Progress of source term identification for safety evaluation 4. R&D milestones and qualification program prior to ITER TBM tests

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Design Conditions of JA Solid Breeder TBMs

Unit Water Cooled He CooledStructural Material F82HCoolant Water He gasNeutron Multiplier Be, or Be12 Ti Tritium Breeder Li2 TiO3 , or other Li ceramicsSHF (aver., max.) MW/m2 0.3, 0.5NWL (aver.) MW/m2 0.78FW Area m2 0.484x1.66 1.208x0.71Coolant Pressure MPa 15.5 8Coolant Temp.Inlet/ Bypass/ Outlet

oC 280 /325 300/395/500(472)

Heat Deposition MW 0.944 1.08Tritium Production Rate

g/FPD 0.134 0.157

Coolant Flow Rate kg/s 3.59 1.3 (Bypass =0.34 )Coolant Holdup m3 1.5 2.9

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Modification of the TBM Dimension

Front view of Common Frame for Vertical Modules

JA Water Cooled Solid Breeder TBM

Module dimension 484 x 1660Radial thickness 600

JA Helium Cooled Solid Breeder TBM

Module dimension 1208 x 710Radial thickness 600

Port 18

Port 16

524

1700

Front view of Common Frame for Horizontal Modules

750

1248

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Concept of JA Solid Breeder TBM’s

First Wall

Concept of Water Cooled Solid Breeder TBM

Plasma side

Tritium Breeder(Li2 TiO3, or other Li ceramic pebble

single size packing, 0.2 2mmφ

depending on the layer width)

Neutron Multiplier(Be, single size pebble bed, 1mmφ)

1st Multiplier Layer

2ndMultiplier

Layer

2nd Breeder Layer

Sub-module structure for internal pressure durability and structure similarity with DEMO blanket (slit structure for electro-magnetic force reduction in DEMO).

2 sub-modules, 2 breeder layers in the WCSB TBM3 sub-modules, 3 breeder layers in the HCSB TBM

1st Breeding Layer

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Structure of Water Cooled Solid Breeder TBM

1st Breeder

1st Multiplier

2nd Breeder

2nd Multiplier

Consists of two sub-modules

Horizontal View

Vertical ViewModule structure is integrated by EB welding.

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Structure of JA He Cooled Solid Breeder RAFM TBM

1st breeder

1st multiplier2nd breeder2nd multiplier3rd breeder3rd multiplier

3 Sub-module Configuration with one set of inlet , outlet and bypass coolant pipes

Horizontal View Vertical ViewEBW at rear wall

Drawings shall be modified.

Coolant pipes are unified to one set for minimizing the pipe penetration through the Back Shield of the Common Frame.

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Test Plan of JA Solid Breder TBM’s

FuCu

Year 1 2 3 4 5 6 7 9 10

Mile Stone First Plasma Full Field, Current & H/CD Power

Short Burn200 MW

Q=10500 MW

Q=10500 MW 400 s

Non-inductiveCurrent Drive

Operation

Equivalent Number of Burn pulses (500 MW x 400 s)Cumulative Neutron Fluence at Test Port (MWa/m2)

1 750 1000 1500 2500 3000 3000

9.9x10-6 0.0074 0.017 0.032 0.057 0.087 0.12

High Duty DTLow Duty DT

D-Plasma(limited T)H-Plasma

Baking & Conditioning

- Machine com- missioning

- Achieve good vacuum & wall condition

- Machine commissioning with plasma

- Heating & CD experiments- Reference scenarios with H

- Commissioning with neutron

- Reference with D

- Short DT burn

- Development of full DT high Q- Development of non-inductive

operation aimed at Q=5- Improvement of inductive and non-

inductive operation- Demonstration of a high duty operation

Installation &Commissioning

Basic Installation & Commissioning For Activation PhaseFor High Duty Operation

Upgrade

Blanket TestPhase

System Checkout & CharacterizationTBM W-1, TBM H-1 TBM W-2,3, TBM H-2,3

Performance TestTBM W-4, TBM H-4- Overall functions,

instrumentation, flow control, heat loss, etc.

- Integrity to EM & thermal loads

- FW heat removal- Ferritic steel effect on

plasma control

- Remote handling test during shut down

- Neutronics environment measurement

- Indication of tritium production & extraction

- Indication of heat generation

- High grade heat generation and extraction

- Continuous tritium recovery- Electricity generation with TBM w-3

System Checkout &Test EnvironmentMeasurement

NeutronicsMeasurement Thermo-mechanical Test

T and Heat Production (long term)TBRTest

TestKey Words

Refurbishment, Replacement

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Possible Neutronics Instrumentation1. Energy spectrum and transient trends of neutron flux are favorable

data. For these data, pneumatic systems and micro fission chambers are possible instrumentation.

Neutronics Instrumentations

2. Pneumatic systems may not be available in ITER, from safety point of view

3. Micro-fission chambers (U235 and U238) for thermal and fast neutron are most possible instrumentation.

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Source Term Evaluation (Tritium and ACP)

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Tritium Control of WCSB TBM

HT, HTO to T Plant

TBM Cooling System

TBM inside V.V. boundary

Com mon Frame

Port Cell Shaft

TCWS Vault

HX

ITER Heat Rejection System

TBM T Recovery System T BuildingGB

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4

5

6

7

1: Plasma P. Cool. 4: Purge Gas out 7: TRS to T plant

2: Breeder P. Cool. 5: P. Cool. out 8: Drain water waste storage

3: Breeder P. Cool. 6: P. Cool. 2 Cool.

Drain Tank

HTO waste storage

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Major source terms: Tritium release in breeder, Permeation to primary coolant

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Tritium Release & Inventory Characteristics

Please see the presentations of Mr. Kinjo, Prof. Nishikawa, Ms. Sasaki in Session 3.

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Estimation of Permeation Rate to Primary Coolant

(1) Permeation into the FW cooling water by implantation was estimated using equations by Doyle and Brice*.J2 =φα[(1+W)/{W+α(γ2+ 1 )}] (1)W=(φR/D1 )(k1 /φ)0.5 (2)α=(R/xo )[(xo /δ)/{exp(xo /δ)-1}] (3)γ=exp(xo /xs )(kl /k2 )0.5 (4)1/δ=1/xD +1/xs (5)xD =xo kB To /ED (6)xs =-xo kB To /Q* (7)To = T1 T2 /(T1 -T2 ) (8)D=1.07 10-7exp(-0.145/kB /T)k=9.40 10-26 (500/T)exp(-0.118/kB T)(2) Permeation from purge gas to cooling tubes was estimated by Serra’s paper**.Φ=DKP-0.5S/xo (9)DK=3.18 10-8exp(-0.4219eV/kB T) mol s-1m-1Pa-0.5 (10)(3) Permeation reduction factor (PRF)

Permeation Rate = (Original Permeation Rate) / (PRF)

*B. L. Doyle, D. K. Brice, Radiation Effects, 89 (1985) 21.**E. Serra et al., J. Nucl. Mater., 245 (1997) 108.

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Currently Available Permeation Data

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Estimated Permeation Rate to Primary Coolant of TBMs

Tritium partial pressure at outlet of purge gas line

WCSB TBMAFW =0.89m2, TFW =293-550ºC,

ABr =1.47m2, TBr =340ºCFlux=1.56x1019/m2s

HCSB TBMAFW =0.95m2, TFW =370-

550ºC, ABr =1.51m2, TBr =510ºC

Flux =1.56x1019/m2sg/FPD/module g/FPD/module

Breeder Layer (T2 = 1 Pa) 6.3x10-5 2.1x10-4

FW implantation 9.6x10-5 4.6x10-4

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Estimated Tritium Permeation Amount to Primary Coolant of TBMs in 0.12 MWa/m2

Tritium partial pressure at outlet of purge gas line

WCSB TBM HCSB TBMBq/m3 in 1FPD* Bq/m3 in 1FPD*

Breeder Layer, T=1Pa 1.26 x 1012 1.47 x 1012 ( 9.62 x 1011)**Bare FW implantation 1.3 x 1012 3.23 x 1012 ( 9.62 x 1011)**

Be 5mm FW implantation*** 4.9 x 1010 – 1.2 x 1011 1.2 x 1011 – 3.0 x 1011

* (1) Water holdup of WCSB primary cooling system is 1.5 m3. (2) Helium holdup of HCSB primary cooling system is 2.9 m3.

** 1Pa T2 partial pressure is equivalent to about 9.62 x 1011 Bq/m3. ***Permeation rate in Be is more than 1 or 2 order of magnitude smaller than Fe.Tritium concentration limit of the in-vessel components cooling water is 1.81 x 1012 Bq/m3.

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Activated Corrosion Products (ACP)

0 500 1000 1500Duration (h)

0

1

2

3

4

Wei

ght g

ain

(mg/

cm2 )

743K

717K

653K

NF616 at 773K

-9Cr1Mo at 839K

108

109

1010

1011

1012

1013

0 10 20 30 40 50 60 70Radial location from FW [cm]

Indu

ced

activ

ity[B

q/cc

]

1 s1 min1 h1 day1 week1 month1 year

FW

Distribution of Total Induced Activation in Water Cooled TBM after 0.3MWa/m2

irradiationMeasured data of corrosion rate of F82H by high pressure and temperature water

From the induced activation analysis and experimental data of corrosion rate, induced activity is estimated to be about 4.1x1013 Bq/kg.

Using corrosion rate data, maximum ACP is estimated 9.64 x 1011 Bq.

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Source term evaluation

Tritium1. In the case of HCSB, maximum accumulation of tritium permeation

can be limited to 9.6x1011 Bq/m3, which is the equilibrium tritium concentration of He purge gas.

2. In the case of WCSB, by using permeation reduction factor of 100, the maximum accumulation of tritium in coolant water can be limited to 1.4x1012 Bq/m3.

3. Currently available permeation data is limited for the most clean surface and the data include the large uncertainty (one or more orders of magnitude). The realistic data with oxidized surface is not evaluated well. Especially the permeation data of gas to high temperature water through the structural material need to be obtained.

ACP1. ACP of WCSB is estimated to be 9.64 x 1011 Bq.

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Time Schedule of Solid Breeder TBM’s Development in Japan

ITERProject

FY 2020

BlanketDevelopmentPhase

20102000

Module #1

2005 2015

ElementalTechnol.

R&D

ConstructionEDA

Module #2Start Fabrication

CTA/ITA

Start Fabrication

Fusion Power Demonstration Plant

TBM TestsOperation

•In-pile R&Ds

•Out-pile R&Ds

Test BlanketFabrication

PrototypeDevelop-ment

Out-pile overall Demonstration Tests

Elemental R&Ds on Fabrication Tech.

Engineering R&Ds with large scale mock-ups

Elemental R&Ds on Irradiation Tech.

Elemental R&Ds

Engineering R&Ds on Irradiation Tech., Pebble Fabrication Tech.

Irradiation Tests on Module #2

TPR Evaluation with a full module structure

OverallsystemTests

TPR evaluation with simulated blanket structure

Demonstration Tests for Basic

Option

Out-pile Overall Demonstration Testsof Advanced Module

Irradiation Tests on Advanced Module

TPR Evaluation with a Full Structure of Advanced Module

Overall system Testsfor Advanced Module

Irradiation in Fission ReactorsIFMIF

Basic Research on Blanket Neutronics

Basic Research on Blanket Tritium Recovery Process

•Tritium Recovery System Development

•Neutronics / Tritium Production Tests with 14MeV neutrons

Optimization Verification Qualification/ImprovementStructuralMaterial R&D(RAF/M)

Blanket R&D

DesignDecision of construction

Engineering R&D

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Major milestones of JA Solid Breeder TBM

OutpileR&D

NeutronicsTest

2009• 1/1 Module Mockup Heat Load Tests (1.3 MW/m2 + simulated internal heating x 3000 cycle)• Be FW HHF test (1.3 MW/m2 x 3000 cycle)

Qualification of TBM integrity

In-pileR&D

2009• Breeder pebble:>0.32%LiBU/1.04 dpa*• Be pebble:320 appmHe/0.8 dpa*• In-situ tritium recovery data by pebble bed mockup >0.12MWa/m2*

Confirmation of tritium recovery and mechanical integrity of beds

2009• Neutronics tests by 14 MeV fusion neutron using simulated TBM mockup

Evaluation of neutronics performance and tritium production rate for TBM structure

*TBM 10 (0.12MWa/m2)

StructuralMaterialR&D

2009• Irradiation data upto 1.2dpa by fission reactor• Extrapolation evaluation to fusion neutron irradiation of 3dpa

Pre-selection of material spec. for DEMO and standard data for TBM structure

2014: Delivery of TBMs to the ITER site2010: Start TBM fabrication2010: Final Design Report/ Safety Report/ Material Specification

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Qualification ProgramMajor Milestones:– 2008 Material Selection Report

• Chemical Composition• Physical Properties• Mechanical Properties, including bonding parts

– 2008 Fabrication Technology Report• Influence of Component Fabrication Process on Physical/Mechanical

Properties• Neutron Irradiation Effects on Physical Properties, up to 1-2 dpa• Corrosion Behavior

– 2010 Final Design Report, Safety Report, Material Specification Report• Detailed design of TBMs, which includes fabrication procedure and

qualification control, and also includes safety evaluation.• Mock-up qualification tests included:

– Fabrication of scalable mock-ups, ~1/2 ~ full size, which should be the same fabrication procedure of the TBM

– Mechanical tests of representative TBM specimens– HHF tests: 0.5MW/m2, 10,000 cycles

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Summary

1. DDDs of Water Cooled Solid Breeder TBM and Helium Cooled Solid Breeder TBM were generated. They include structure design of thermo-mechanical TBMs, their performance analyses and R&D achievements and plan.

2. For diagnostic system of TBM, micro fission chamber system is considered. It is necessary to assess the availability of pneumatic system for activation foil measurement.

3. Information for safety assessment of TBMs, for ITER preliminary safety report (RPrS), are being prepared. Interim reports for WCSB and HCSB were submitted.

4. Qualification program has been defined, on the basis of the R&D achievement, toward TBM construction.