Recent progress of tritium related

activities in Japan

Kenji Okuno

Shizuoka University

Radio-science Research Laboratory

3rd-China-Japan WS

Kunming, China, June 20-23,2010

Research Subjects and Institutes

for Tritium Issues

Research Subjects

- Fusion

(Processing, Blanket, First Wall, Safety, Licensing)

- Fission Reactor (Heavy Water Reactor)

- Waste Management

- Environmental Behavior

- Biological Effects

- Fundamental Science

Institutes

- Universities

- Japan Atomic Energy Agency

- National Institute for Fusion Science (NIFS)

- National Institute of Radiological Sciences (NIRS)

Tritium/Material Interaction

- Plasma Facing Materials

- Structural Materials

Blanket Engineering

- Breeding Materials

- Tritium Breeding Ratio

- Tritium Recovery

- Tritium Permeation

Tritium Processing and Safety

Tritium Behavior in Environment

Key tritium issue

for Fusion Engineering Researches

Institutes and Universities where Tritium

Related Studies are conducted in Japan

JAEAJAEA

Akita Univ.

Research Resources

JAEA 50

NIRS 10

Industries many

University Researchers Students

Hokkaido U. 3 4

Akita U. 2 4

Tohoku U. 1 2

Ibaraki U. 6 6

U. of Tokyo 7 15

Shizuoka U. 4 12

Toyama U. 9 7

NIFS 7 0

Nagoya U. 7 10

Kyoto U. 7 7

Osaka U. 2 1

Hiroshima U. 2 2

Kyushu U. 9 8

Total 66 78

Tritium Network in Japan

JAEAUniversities

NIFS

National

InstitutesIndustries

Academic Societies・Atomic Energy Society of Japan

・The Japan Society of Plasma

Science and Nuclear Fusion

Research

・The Japan Radiation Research

Society

Conferences (International

and Domestic)・Tritium Science and Technology

・ISFNT

・Joint Symposium, ・・・・・

Many International Collaborations

-CUP (Core Universities Program)

-MEXT/Korea-STA

-MEXT/US-DOE: TITAN Project

-JAEA and foreign countries

-ITER

BA program

-Between Universities

-International Conferences and Symposiums

Tritium conference at Nara in Oct. 2010

Tritium mini-WS, TOFE, ICFRM, ISFNT, et. al.

International collaboration researches

TITAN Project

Tritium, Irradiation and Thermofluid for America and Nippon

To obtain fundamental understanding for establishing tritium and

thermofluid control throughout the first wall, blanket, and heat

exchange/T-recovery system of MFE and IFE systems by experiments

under specific conditions to fusion, such as irradiation, pulse high heat

flux, circulation and high magnetic field.

The results will be applied through the integrated modeling to advance-

ment of design for tritium and heat control of MFE and IFE systems.

Objectives of TITAN project

Shield

Magnet

storage

pump

Heat exchanger

14MeV neutrons

turbine

Blanket

HeatTritium

Heat

TritiumBlanket

First Wall

Recovery systemPlasma

Recovery system

JUPITER-II

Next Project

pump

purification

First Wall

HeatTritium

TITAN Project will

focus on consistency

of the blankets with

first wall and recovery

systems with respect

to tritium and heat

control

TITAN Structure (revised on Feb.12, 2009)RepresentativesCoordinators

JP : K. Okuno (Sizuoka U.) US : G. Nardella/B. Sullivan (USDOE)JP : T. Muroga (NIFS) US : D. Sze (UCSD)

Task Subtask Facility TC (JP) STC/Deputy (JP) TC (US) STC/Deputy (US)

Task 1Transport phenomena

1-1 Tritium and mass transfer in first wall

TPEPISCES

T. Terai(U.Tokyo)

Y. Ueda (Osaka U.)/N. Ohno (Nagoya U.)K. Tokunaga (Kyushu U.)

D. Sze(UCSD)

R. Doerner(UCSD)

1-2 Tritium behaviorin blanket systems

STAR T. Terai (U. Tokyo)/S. Fukada (Kyushu U.) S. Konishi (Kyoto U.)

P. Sharpe(INL)/P. Calderoni(INL)

1-3 Flow control and thermofluid modeling

MTOR T. Kunugi (Kyoto U.)/T. Yokomine(kyushu U.)

N. Morley (UCLA)/K. Messadek(UCLA)

Task 2Irradiation synergism

2-1 Irradiation-tritium synergism

HFIRSTAR

A.Kimura(Kyoto U.)

Y. Hatano (Toyama U.)/Y. Oya (Shizuoka U.)

R. Kurtz(PNNL)

M. Sokolov (ORNL)/ Y. Katoh (ORNL)P. Calderoni (INL)

2-2 Joining and coating integrity

HFIRORNL-HL(incl. T-test)

A. Kimura (Kyoto U.)/N. Hashimoto(Hokkaido U.)

T. Yamamoto (UCSB)/M. Sokolov (ORNL)

2-3 Dynamic deformation

A.Hasegawa (Tohoku U.)/T. Hinoki (kyoto U.)

Y. Katoh (ORNL)

Common TaskSystem integration modeling

MFE/IFE system integration modeling

A.Sagara(NIFS)

A. Sagara (NIFS)/H. Hashizume(Tohoku U)T. Norimatsu (Osaka U.)

R. Nygren(SNL)

R. Nygren (SNL)

Laboratory Liaisons

ORNL : R. Stoller (ORNL)INL : P. Sharpe (INL)IMR-Oarai (Tohoku) : T. Shikama (Tohoku U.)

IFE Liaisons

K. Tanaka

(Osaka U.)

Kodama(Osaka U.)

Yoneda(UTC)

M. Tillack

(UCSD)

Hokkaido University

Research activities at

Laboratory of Plasma Physics

and Engineering, Hokkaido

University

T.Hino

Hokkaido University

Plasma – material interactions and heat &

particle controls in fusion devices have been

investigated in this laboratory since 1980.

The research program includes the

collaboration studies with National Institute

for Fusion Science (Toki) and Japan Atomic

Energy Agency (Naka).

The present major research staffs are

T. Hino (Professor), Y. Yamauchi (Associate

Professor) and Y. Nobuta (Assistant Professor).

Overview

Present Researches

(1)Fuel hydrogen retention and desorption

behavior in LHD

Hydrogen retention and desorption of the first wall

are investigated using numerous material probes

and a technique of thermal desorption.

(2)Reduction of tritium inventory by glow

discharge conditionings

The fuel hydrogen retention in plasma facing

materials (SS, W, C) is reduced by the glow

discharge using inert gas such as He, Ne and Ar.

Reduction of fuel hydrogen retention in W will be

presented in this workshop.

(3)Tritium inventory of carbon dust

Numerous carbon dusts are prepared by a

deuterium arc device with carbon electrodes.

Discussed is the relation of the hydrogen

concentration with preparation conditions such as

discharge gas pressure and substrate temperature.

(4)Plasma – wall interactions of low

activation materials

Fuel hydrogen retention and desorption behavior is

investigated for ferritic steel, vanadium alloy and

SiC/SiC composite.

(5)Diagnostics of radiation power from

boundary plasma

Infrared bolometer has been developed as the

boundary plasma diagnostics.

Akita University

Activity in Akita University (1)

• There is a facility for handling of radioactive material

in the university. The facility was constructed in 1989.

• A new activity for permission and authorization for

handling of tritium had started in October 2009,

which was finally authorized in March 2010.

• At present, they can handle tritium of 3.7 GBq daily,

27 GBq in three months and 55.5 GBq annually. Our

storage capacity of tritium is 185 GBq.

• They are cooperating with National Institute for

Fusion Science (NIFS), Kyoto University Research

Reactor (KUR), Japan Atomic Energy Agency (JAEA),

Forschungszentrum Karlsruhe (FzK) in Germany and

Shizuoka University.

Activity in Akita University (2)

• (1) R&D related to air cleanup system and

process gas cleanup system (NIFS)

Experimental work with tritium, Honeycomb

catalyst and adsorbent, Process simulation

• (2) R&D related to new neutron multipliers

for fusion blankets (JAEA)

Experimental work, Process simulation,

Quantum chemistry calculation

• (3) Experimental investigation on tritium

behavior in chambers using Caisson

Assembly for Tritium Safety study (CATS)

and its numerical simulation (TPL, JAEA)

Experimental work with tritium, Process

simulation

Activity in Akita University (3)

• (4) Modeling of membrane reactor for

treatment of plasma exhaust gases (FzK)

Process simulation

• (5) Study on behavior of tritium release from

ceramic breeders (Shizuoka University and

KUR)

Experimental work with tritium, Irradiation

in research reactor, Process simulation,

Quantum chemistry calculation

• (6) Study on adsorption of hydrogen

isotopes at cryogenic temperature

Experimental work, New adsorbent, New

process, Process simulation

The University of Tokyo

- Prof. Tanaka Laboratory

- Profs. Terai and Suzuki

Laboratory

[Tanaka Lab., Univ. Tokyo] “Tritium in liqiud Li-Pb”

＜Calculation condition＞

CASTEP code

DFT （GGA-PBE）

Plane-wave base

Pseudopotential （ultrasoft)

Periodic boundary condition

(Li6Pb30 >> Li17Pb83)

NVT ensemble (1 fs, 900 K)

: Hydrogen atom

: Lithium atom

: Lead atom

It is difficult to observe hydrogen in liquid materials by experiment.

Hence, existence states and diffusion mechanism are not well understood.

“Direct observation” by ab-initio molecular dynamics [QM-MD]

(*ab-initio = quantum mechanics)

[Tanaka Lab., Univ. Tokyo] “Tritium permeation/leakage”

LiAlO2 by Mr. Tsuchihira

[Tanaka Lab., Univ. Tokyo] “Radiation damage in breeders”

Flibe (234g, 873K)

He + 0-100%H 2 + 0-2%HF

Molecular sieve bed

Aluminium bed (673K)

Ionization chamber A

Tritium trapping system Ionization chamber B

Gas supply system

Sample container

Reactor core

Polyethylene block

NiF2 bed (673K)

n = 108-11 n/cm2 sec, Tirr = room temp. to 800 C

Materials investigated: Li2O, Li2TiO3, Li, Li-Pb, Flibe (LiF-BeF2)

Tritium production rate (in comparison with MCNP calculation),

tritium chemical species released, kinetic parameters (D, Ks, K,

mass-transfer coefficient from liquid to purge gas), tritium

permeation through structural materials were investigated.

In-situ tritium release behavior from tritium breeders

under neutron irradiation at high temperature

core neutron

- PbLi natural convection loop is operated under neutron irradiation

- Tritium permeated through wall of the loop is detected

Tritium separating

/detecting system

50cm

Fast neutron source

“YAYOI”

Tritium production experiments from PbLi

under flowing conditions

Filtered arc deposition device

(IPP-Garching, Germany)

Development of Tritium Permeation Barrier

Er

Fe

1mm

Material: Erbium oxide (Er2O3)· Thermodynamically stable

· Efficient suppression of hydrogen

· Lower deposition temperature

than other oxides (ex. Al2O3)

SEM

1.0 1.2 1.4 1.6 1.8

10-15

10-14

10-13

10-12

10-11

10-10

Perm

eabili

ty (

mo

l/m

/s/P

a0

.5)

1000/T (1/K)

973 873 773 673 573

T [K]

■ F82H

▲ 1.3 mm one side

▼ 2.6 mm one side

● 1.3/1.3 mm both

◆ 2.6/2.6 mm both

D2

Gauge 1 Gauge 3

QMS

Calibration

Volume

TMP 2TMP 1

Upstream Downstream

Furnace

SampleGauge 2

RP 2RP 1

103~105 Pa <10－6 Pa

Jbare / Jcoated ~105

Er2O3 coatings have a potential

as a tritium permeation barrier

Deuterium permeation setup Permeation results

University of Toyama

Hydrogen Isotope Research Center (HRC),

University of Toyama

HRC is one of the largest tritium research facilities in Japanese universities and

licensed to handle 8 TBq (217 Ci) tritium per day and 555 TBq (15 kCi) per year.

The center was established at 1980, and this year is in celebration of 30 years

anniversary. Safety equipments including ventilation, waste water processing and

tritium monitoring systems in the radiation facility are currently under

full-reconstruction for stable operation in the future.

Uniqueness of Facility

(1) Handling of tritium in any chemical/physical

form

(2) Various instruments for tritium measurements

(gas, liquid and solid)

(3) Various tools for material characterization in

tritium laboratory.

7 Full, associate and assistant professors,

1 Posdoc, 2 Technicians, Secretaries

(2) Tritium ad/absorption, diffusion, permeation and release in/from fusion

materials

Tungsten, Austenitic and Ferritic Steels, Be alloys, Concretes etc.

Influence of ion/neutron irradiations (Hatano, this workshop)

(3) Development of T permeation barrier coatings and low

adsorption/solubility/diffusivity materials (Zhang, this workshop)

(4) Application of tritium to materials science (e. g. visualization of hydrogen

isotopes in solids by autoradiography)

(5) Development of functional materials for hydrogen energy systems

(hydrogen separation membranes, photocatalysts for hydrogen production etc. ).

Current Research Topics

(1) Tritium measurements

Development of a high sensitivity calorimeter for

absolute measurement (Matsuyama, this workshop)

b-ray-induced X-ray spectrometry (BIXS) and imaging

plate (IP) technique for tritium measurements in liquids

and solids, and near-IR spectroscopy for HTO detection

HRC started new collaboration systems

International Collaboration

(1) Foreign Guest Professor Position

(2) Visitors by Personal Exchange Program including Japan-China

Core University Program and Japan-US Project TITAN.

Domestic Collaboration

(1) Tritium for Fusion

Bidrectional collaborative research program of NIFS (NIFS, the

national user facility for fusion research financially supports

collaboration in HRC)

(2) Tritium for Physics, Chemistry and Material Science, Hydrogen

Energy

Joint Usage/Research Program of HRC

Shizuoka University

Radiochemical Research Laboratory of Shizuoka University

Research activities of Okuno &Oya Lab.

at Shizuoka University

Prof. Kenji Okuno Assoc. Prof. Yasuhisa Oya

Radiochemistry Research Laboratory,

Faculty of Science, Shizuoka University

Typical Research topics at Shizuoka University

Wall conditioning

→Boronization

- Impurity effect on fuel retention

D,T, He

Impurities

PWI issues

- Simultaneous ion implantation

(D, T, He, C) effects on fuel retention

neutron

Blanket issues

- Tritium recovery from lithium oxides

- Behavior of irradiation defects

Tritium permeation behavior

through vacuum vessel

Tritium behavior in fusion related materials

based on radiochemical aspects

Tritium retention behavior in tungsten under simultaneous ion

implantation conditions

300 500 700 900 11000

2

4

6

8Simultaneous

implantation

C, D, He

D, He

C, D

D

Des

orp

tio

n r

ate

/ 1

01

7 D

2 m

-2 s

-1

Tempreture / K

0 5 10 15 20

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

C in C-D imp. W

C in C-He-D imp. W

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

D in D imp. W

D in He-D imp. W

D in C-D imp. W

D in C-He-D imp. W

Depth / nm

Inte

nsi

ty /

arb

. u

nit

TEM micrographs for the simultaneous C+-D2

+ and C+-D2+-He+ implanted samples.

D2 TDS spectra for the simultaneous C+-D2

+, D2+-He+ and C+-D2

+-He+ implanted

tungsten samples

To simulate actual environment of plasma facing materials under fusion

relevant conditions, simultaneous ion implantation of C+, He+, and D2+

were performed with various ion implantation conditions.

Simultaneous ion implantation system

Depth profiles of C and D in tungsten with various ion

implantation conditions

・The D retention was increased by simultaneous ion implantation.

・Most of D would be trapped by interstitial site and/or irradiation

defects.

・For the D trapping by C, C sputtering by C+ and/or He + and He +

accumulation should be taken into consideration This is a collaboration research with

Kyushu University, University of

Toyama and NIFS.

Plasma CVD system for boron deposition

Tritium retention behavior in boron for wall conditioning

400 600 800 1000 12000.0

1.0

2.0

3.0

4.0

5.0

Temperature / K

Des

orp

tion

rate

/ 1

018 D

2 m

-2 s

-1 TDS spectrum B-D-B bond B-D bond

400 600 800 1000 12000.0

0.5

1.0

1.5

2.0

2.5

3.0

Des

orp

tio

n r

ate

/ 1

01

7 D

2 m

-2 s

-1

Temperature / K

TDS spectrum

B-D-B bond

B-D bond

B-O-D bond

400 600 800 1000 12000.0

0.5

1.0

1.5

2.0 TDS spectrum

B-D-B bond

B-D bond

B-C-D bond

Temperature / K

Deso

rpti

on

rate

/ 1

01

8 D

2 m

-2 s

-1

- Boronization has been applied as one of the most effective techniques for first wall

conditioning for various fusion devices like LHD (NIFS), EAST (ASIPP) and so on.

- Boron is easily bonded to impurities, such as oxygen and carbon, in vacuum vessel and

the elucidation of impurity effect on tritium retention in boron is one of critical issues.

(a) Pure boron film (b) 25% oxygen contained boron (c) 35% carbon contained boron

400 600 800 1000 12000.0

1.0

2.0

3.0

4.0 Pure boron film

LHD boron film

Deso

rpti

on

rate

/ 1

01

8 D

2 m

-2 s-1

Temperature / K

No.11 Campaign

First wall position（2800 mm) Inlet gas： B2H6

Substrate temperature： 373 K

Substrate： Si（99.999%）

LHD sample : 30%, O: 27%, C: 39% N: 3%

Comparison of D2 TDS spectra for various boron films

Comparison of D2 TDS spectra for pure boron film and LHD boron film

The D was bound to impurities as B-O-D and B-C-D and higher temperature is required for desorption.

The D retention for LHD boron film was clearly decreased, which indicated that some of D was quickly re-emitted as H2O and

CDx during the operation.

g-ray irradiation

excitation state

Formation processes of defects

nth

6Li 6Li(n,a)T

He T

6Li

He T

e-

OM

M

hO

MO

- Elucidation of tritium recovery mechanism is one of important

issues for fuel management in fusion.

- Irradiation defects would play an important role in the

trapping and detrapping of tritium

300 400 500 600 7000.0

0.2

0.4

0.6

0.8

1.0

The a

mount of irra

dia

tion d

efe

ct / -

Annealing temperature / K

O-related defects(Thermal neutron irr.)

E'-center(Thermal neutron irr.)

O-related defects(g ray irr.)

E'-center(g ray irr.)

The normalized intensities for E’-center and O--center for thermal neutron and g-ray irradiated samples as a function of annealing

temperature.

O--center

E’-center2.06 2.04 2.02 2.00 1.98 1.96

-0.2

-0.1

0.0

0.1

0.2

g-ray irr.

Un-irr.

Inte

nsity / a

rb.u

nit

g value / -

ESR spectra for the un-irradiated and the g-ray irradiated samples

Fundamental study for the annihilation of irradiation

defects in Li2TiO3 was performed.

The defects induced by g-ray annealed in higher

temperature region than those by thermal neutron,

indicating that formation processes were important in

the trapping and detrapping of tritium.

Correlation between tritium release and annihilation of

irradiation defects in lithium oxide (Li2TiO3)

Kyusyu University

- Prof. Fukada Laboratory

- Prof. Momoshima Group

Kyushu University tritium activity : (1) Clarifying behavior of tritium release from

blanket materials and developing mew tritium recovery method

tritium extraction

1st wall

tritium generation

rate

Flibe

Be

reactor core

leak rate < 10Ci/day

FFHR-2

6.5m3/s (12.8t/s)

500o

C

600o

C

3GWt

pump

heat exchanger

4.5MCi/day

gas turbine

Generator~

cooler

compressor

He (3.3 t/s)

tritium permeation

220oC

395oC

Flibe loop for FFHR-2 and He Brayton

cycle

99.9998% T removal

permeation barrier

Flibe

Radioactivity of tritium released from neutron-irradiated Flibe

(2LiF+BeF2 mixed molten salt) under under Ar + H2 purge at

300oC. Experiment and calculation are in good agreement.

•FFHR is a conceptual design of

stellarator-type fusion reactor designed

by NIFS.

•This is operated under steady-state

high beta plasma confinement.

Flibe has low tritium solubility

and counter-current tower for

Flibe-He bubble extraction is

under design.

Kyushu university activity, 3rd china-Japan tritium workshop in Kunming China, June 21,

2010

leak leak

envi

ron

men

t

enviro

nm

ent

environmen

t

Porous concrete wall

leak

Containment cell

T

TD

T

D

T

HHO

Kyushu University activity : (2) Tritium containment in concrete block with hydrophobic

paints

HTHTO

CH3T

Concrete pellets with or without paints

are exposed to HTO vapor atmosphere

Globe box

HTO vapor exposure experiment

Hydrophobic paint coating

HTO dissolution from concrete pellets to water

•HTO transfer in porous concrete materials can be predicted by the diffusion model.•Epoxy paint coating is preferable to reduce HTO transfer in concrete.•The reduction factor is around 1/10.

results

•It is necessary to contain tritium safely in the tertiary enclosure composed of concrete walls in case of accidental tritium release.•The present experiment clarifies how the released tritium is transferred through concrete walls and how well hydrophobic paints coated on concrete can protect tritium transfer in walls.

Kyushu university activity, 3rd china-Japan tritium workshop in Kunming China, June 21, 2010

Behavior of Environmental Tritium

and Assessment of Influence on

Environment

Research groups

Sugihara, S., Momoshima, N. (RIC, Kyushu Univ.)

Amano, H., Ando, M. (JAEA)

Miyamoto, K. (NIRS)

Takahashi, T.,Fukutani, S. (Kyoto Univ.)

Shimada, J. (Kumamoto Univ.)

Tamari, T. (KEEA)

Uda, T., Sakuma, Y., Yamanishi, H., Tanaka, M (NIFS)

Purposes

- to develop the technique to evaluate the

environmental tritium behavior of the facility

origin.

seasonal variation

year change

climate change in the environmental tritium

- to verify safety than the level of the other

domestic area in the change level with tritium

concentration around the facilities.

Determination of tritium concentration of 34 river

waters and 6 lake waters in Japan

Fig. Tritium concentrations in river

and lake samples

Japan Atomic Energy Agency

JAEA

45

~ 12 PBq (2009 March)

4.91 EBq/year

Tritium Process Laboratory (TPL) of JAEA

Building of TPL

Glove Box

46

0

20

40

60

80

88 90 92 94 96 98 00 02 04 06Am

ount

of

trit

ium

rel

ease

d

(GB

q)

Fiscal year

HTO

HT

Average concentration of tritium at stack =

60 Bq/m3 (1/100 of regulation value).

From experimental apparatus

CompressorFrom glove box

Catalysts

473 K and

773 KMolecular sieve bed

To stack

Cooler Pre-heater

Vessel

Recycle operationConceptual flow diagram of

tritium removal system

Amount of tritium released from stack

47

1) A series of safe operation of tritium has been demonstrated at TPL.

2) The design studies of ITER Detritiation system, and ITER TBM

system have been continued at TPL.

3)Some basic studies on tritium safety technologies have also been

carried out at TPL.

Detailed information will be presented by Dr. Yamanishi later.

Schematic of Blanket Tritium Recovery

System using Hydrogen Pump for ITER-

TBM

Basic research for tritium

safety related to BA program

–tritium permeation behavior

into cooling water

oxide layer growth

(magnetite, 1.7mm)

on iron after 20 h in

water jacket at 423K

Thank you for your attention!!

We always welcome you to visit Japan and keep in touch

with you to develop tritium technology and related issues.