W. T. ShmaydaUniversity of RochesterLaboratory for Laser Energetics

Tritium Focus Group WorkshopGermantown, Maryland

2325 April 2013

Overview of Tritium Activities at the Laboratory for Laser Energetics

E21964

LLE has operated a 1.5-g tritium facility since 2006 without a reportable incident

Handling tritium gas over a 500C temperature range and a 1000-atm pressure range poses unique challenges

Volatile organic species and decay helium contaminate the DT fuel; a Pd permeator has been installed to remove these impurities

LLEs tritium handling capabilities have expanded to address new programmatic needs:

DT layering studies

de-protination of the DT fuel

the study of DT fusion branching ratios

Tritium operations are an integral part of the Inertial Confinement Fusion Program at LLE

Summary

The Laboratory for Laser Energetics operates two of the worlds largest lasers for high-energy-density-physics research

E19929c

Faculty-equivalent staff: 112

Professional staff: 167

Associated faculty: 21

Contract professionals: 10

Graduate and undergraduate students: 127

OMEGA Laser Bay Main

amplifiers

OMEGA EPLaser Bay

Compressionchamber

OMEGA EPtargetchamber

Boosteramplifiers

Beam 1 23 4

OMEGA targetchamber

Operate the National Laser Users Facility

Conduct research and development in high-energy-density phenomena

Provide undergraduate and graduate education in electro-optics, lasers, plasma physics, and fusion technology

Conduct experiments in support of the National Inertial Confinement Fusion (ICF) Program

Gloveboxcleanup getters

Helium

P

T

AirlockBubblers

2 kPa

DP

Drier ZrFe

Ni

Ni

ZrFe

TFS process loop

T

DP

Legend:DP = dew pointT = tritium monitorP = pressure sensor

Processgetters

Glovebox

To stack

DP

T

U-bed Assay

U-bedColdfinger

RT permeation

cell

In 1996 LLE commissioned the Tritium Fill System (TFS) to permeation fill gas targets; since 2006 the TFS also delivers measured aliquots of gas to the DT high-pressure system (DTHPS) for cryo targets

E13735b

TFS functions store tritium assay tritium permeation fill gas targets (

Targets filled with DT gas are routinely fielded to study the physics of DT implosions

E11597h

Warm targets

diagnostic development

field 10 to 12 per campaign

10 to 20 atm DT

All effluent streams are scrubbed to ensure LLE does not exceed its 9.6-Ci emission limit

Low-T vacuum

High-T vacuum

Air/vacuum

Tank

Process-loop effluents

Catalyticreactor

Tank

Clean He

To stack

ZrFebed

ZrFebed

Drier

Drier

Drier

Drier

Nibed

The presence of air determines which technology is deployed to remove tritium from the effluent stream.

Effluentair mixtures Effluent without air

catalytic oxidation

drier

drier to remove HTO

Ni to remove O2 and crack organics

ZrFe to capture hydrogen gasE16057a

A Pd/Ag permeator has been installed to remove organic impurities and decay helium from the DT fuel

G6218m

TFS glovebox

U-bed 1

FTS glovebox

Cryostat

DTHPS glovebox

Secondary containment (comprised of three separate volumes)

Condensationtube

Pre

ssu

reel

emen

t

Syringe pumpMotor-

operatedvalve

Permeation cell

Condensation tube

Upstream pressureRun 1: 3.80 atmRun 2: 3.24 atm

0 5 10 15 20Time (min)

Red

uce

d p

ress

ure

(at

m)

1.0

0.8

0.6

0.4

0.2

0.0

Run 2

Run 1Theory

AssayU-bed 2

Tritium fill system

150 cm2350CMaximum allowableworking pressure: 28 atm, 420C

DT high-pressure system

Permeator

LLE has activated a new tritium laboratory to address expanding programmatic needs

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3.2-Ci release limit; real-time monitoring of T emissions

Lab is 0.05-in. H2O negative relative to adjacent labs; seven air changes per hour

Primary-loop effluents treated by dedicated tritium capture equipment

Treated primary-loop effluents discharged into attendant independent glovebox cleanup systems

Gas chromatograph

DT cryolayeringfacility

Isotope separation system

The glovebox purification systems are integrated, rack-mounted, engineered systems

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The mass transfer zone and capacity for oxygen uptake increase with temperature; higher operating temperatures are preferred

Increasing the hydrogen concentration in the carrier increases the nickel reduction rate linearly at higher flow rates

StackMetal

bellowspump

Drier Ni bed ZrFe bed

Tritium monitor

Tritium monitor

Helium

Checkvalve

From glovebox From gloveboxDP sensor

From processeffluent treatment

1.0

0.5

0.00 100 200 300

Time (min) Flow rate of hydrogen (scc/min)

Oxy

gen

co

nte

nt

in c

arri

er (

%)

36

18

00 25 50

Par

tial

pre

ssu

re

of

wat

er (n

Torr

)30C

400C

200C0.5 sLPM

2.0 sLMP2.0 sLPM

1.0 sLPM1% O2

in heliumat 5 LPM

A DT cryolayering facility will study advanced cryogenic target designs to be fielded on the National Ignition Facility (NIF)

E21985

Targets being examined include:

polar-drive targets

capsules in transparent hohlraums

cone-in-shell targets

NIF baseline: All cryogenic targets are fueled using a fill tube.

A test stand to produce and characterize the advanced cryogenic targets has been constructed and tested with D2

E21986

Optical and x-ray wavelengths are used to characterize targets

Low-vibrationcryocooler

Shadowgraphyoptics

X-ray source

X-ray camera

X-ray shieldedoptical tube

xyz positioner

The layering sphere is thermally isolated, controlled separately, and provides primary containment for the DT

E21987

Layering sphere

Berylliumdiagnostic

windowSolenoid

to activate armature

Fill-tube assembly

Internal rotation allows for 3-D

characterizationof the ice layer

The target assembly comprises four gas compartments: D2 and T2 reservoirs, shell, and cover assembly

E21971

Metal seals are used throughout. The leak rate between adjacent compartments and the exterior is

The tritium dispensing loop uses a Pd bed for all dispensing and recovery operations; T2 is stored on U

E21988

Pd

US UR

P

P20 cc

20 ccTMTM

Glove box boundary

To glove box cleanup

To stack ZrFe

Vacuumsystem

Checkvalve

Pd bed cooldown time

Run time (min)

Tem

per

atu

re (

K)

0 50 100 150

Cooldowntime constant

= 60 min50

100

500400300

200

An isotope separation system (ISS) will provide LLE with a flexible tritium fuel supply

E21968

Ensure the D/T ratio of the fuel supply meets LLEs baseline ICF program requirements

Eliminate protium from the existing fuel supply

Recover tritium from existing, unusable spent DT fuel

Eliminate the need to ship tritium to/from external cleanup facilities

Provide the ability to examine fusion reactions at variable D/T ratios

The ISS can process 5 L/day and supports several novel features

G9879a

Acoustically drive cryogenic cooler to cool Pd bed to 77 K

500-psig ASME certified tritium monitor

20 cc wall-less high-activity

tritium monitor

ISS based on Savannah River National Lab (SRNL) nTCAP design

The gas handling system used to support the ISS comprises flow through uranium and palladium beds

E21972

Both beds have a maximum working inventory of 5 liters of hydrogen gas

Beds have a secondary containment to capture permeant tritium and for thermal isolation

Compact design to permit gas circulation through the getter medium

The uranium bed will be used for tritium storage

The palladium bed will be used to pump tritium inside the gas handling loop

Flow though U-bed cross section

The gas chromatograph permits baseline separation of all six hydrogen isologues

E14977b

50 75 1001.861.75

1.50

1.25

1.00

0.75

0.50m

V

H2 (

42

.44

0)

HD

(5

1.3

20

)

HT

(5

7.7

73

)

D2 (

69

.18

7)

DT

(8

0.2

53

)

T2 (

92

.97

3)

Time (min)

1/8-in.-diam nickel columncontains Fe-doped Al2O3

Zr-Febasedeffluent collector

Aluminum mandrel provides uniform temperature for the column

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Summary/Conclusions

LLE has operated a 1.5-g tritium facility since 2006 without a reportable incident

Handling tritium gas over a 500C temperature range and a 1000-atm pressure range poses unique challenges

Volatile organic species and decay helium contaminate the DT fuel; a Pd permeator has been installed to remove these impurities

LLEs tritium handling capabilities have expanded to address new programmatic needs:

DT layering studies

de-protination of the DT fuel

the study of DT fusion branching ratios

Tritium operations are an integral part of the Inertial Confinement Fusion Program at LLE