Index: Status report ENEA tasks (Dec 2005) EFDA Task TW4 TSS SEA5.1............................slides 2,3,4 EFDA Task TW5 TSS SEA5.1............................slides

Index: Status report ENEA tasks (Dec 2005)

EFDA Task TW4 TSS SEA5.1 ............................slides 2,3,4

EFDA Task TW5 TSS SEA5.1 ............................slides 5,6,7,8

EFDA Task TW4 TSS SEA5.5 (CONSEN).......slides 9,10

EFDA Task TW5 TSS SEA5.5 (CONSEN).......slides 11,12

EFDA Task TW4 TSS SEA2.1A .........................slides 13,14,15

EFDA Task TW4 TSS SEA2 ...............................slides 16,17,18

EFDA Task TW4 TSS SEA4.1 ............................slides 19,20,21

EFDA Task TW5 TSS SEA5.5 (ANITA)..........slides 22,23

EFDA Task TW4-TSW-001 D2-D3....................slides 24,25

EFDA Task TW4 TSS SEA5.1Dust mobilization and transport experiments in the STARDUST device

It is dedicated to test the active extraction of dusts from the volume used as vacuum vessel. The scope is to demonstrate the possibility to clean the ITER vacuum vessel from the accumulated dusts, generated during the plasma disruption, blowing air inside the volume.

The data will be collected also for the validation of the codes simulating the dust transportation in LOVA accidents.

Scope of the task

Test matrixand

experimental procedure

Test duration

(m)

Tungsten Carbon Stainless steel

Ambient temp.

50 °CAmbient

temp.50 °C

Ambient temp.

50 °C

10 W_10_a W_10_h C_10_a C_10_h SS_10_a SS_10_h

30 W_30_a W_30_h C_30_a C_30_h SS_30_a SS_30_h

60 W_60_a W_60_h C_60_a C_60_h SS_60_a SS_60_h

Test duration

(m)

Tungsten Carbon Stainless steel

Ambient temp.

50 °CAmbient

temp.50 °C

Ambient temp.

50 °C

10 W_10_a W_10_h C_10_a C_10_h SS_10_a SS_10_h

30 W_30_a W_30_h C_30_a C_30_h SS_30_a SS_30_h

60 W_60_a W_60_h C_60_a C_60_h SS_60_a SS_60_h

Test duration

(m)

Test duration

(m)

TungstenTungsten CarbonCarbon Stainless steelStainless steel

Ambient temp.

Ambient temp.

50 °C50 °CAmbient

temp.Ambient

temp.50 °C50 °C

Ambient temp.

Ambient temp.

50 °C50 °C

1010 W_10_aW_10_a W_10_hW_10_h C_10_aC_10_a C_10_hC_10_h SS_10_aSS_10_a SS_10_hSS_10_h



• Dust placed in the bottom of the vacuum vessel tank

• Air inlet at the divertor level

• Filter weighted before and after the test

• 1 g of W or C or SS dust in each experiment

• Air inflow for 10, 30 or 60 minutes

• VV temperatures: ambient (~ 20 °C) and 50 °C

• Simulations performed (next slide), experiments on going.


The results obtained by means of the ECART simulations suggested that, using an air flow of the order of 0.04 kg/s, as designed in the STARDUST facility, the cleaning interval has to exceed 2000 s.

W suspended mass (ECART simulations)

Suspended mass (W) Case 20 °C

1.00E-11

1.00E-09

1.00E-07

1.00E-05

1.00E-03

1.00E-01

1.00E+01

1 10 100 1000 10000

tim e (s)

mas

s (

g)

'W VV3'

'W VV1'

'W VV2'

'W PIPE2'

'W GROUND'

Suspended mass (W)Case 50 °C

1.00E-11

1.00E-09

1.00E-07

1.00E-05

1.00E-03

1.00E-01

1.00E+01

1 10 100 1000 10000

time (s)

mas

s (g

)'W VV3'

'W VV1'

'W VV2'

'W PIPE2'

'W GROUND'

In the In the cold testcold test the dust is the dust is pulled out pulled out more rapidlymore rapidly, for , for the reduced turbolence. the reduced turbolence. In about In about 2000 s2000 s the the transient is transient is stablestable..


Feasibility study for a closer geometry to ITER (i.e. Feasibility study for a closer geometry to ITER (i.e. toroidaltoroidal), together with the development of a ), together with the development of a suitable suitable diagnosticdiagnostic on line for dust concentration measurement on line for dust concentration measurement

Scope milestone 1Scope milestone 1

Scope milestone 2Scope milestone 2•Further Further experimentsexperiments in STARDUST to reduce the in STARDUST to reduce the uncertainties uncertainties in dust transport inside and outside the VV: in dust transport inside and outside the VV: mobilization factor and dust exiting the VV under typical ITER mobilization factor and dust exiting the VV under typical ITER accident conditions (i.e. pressurization rates accident conditions (i.e. pressurization rates 10 – 30 Pa/s10 – 30 Pa/s). ).

•The geometry of the experiment takes into account some The geometry of the experiment takes into account some characteristics of the ITER VV, like the presence of characteristics of the ITER VV, like the presence of obstaclesobstacles (e.g. Divertor) and (e.g. Divertor) and layer layer of dusts. of dusts.

• Experiments with Experiments with tungsten, stainless steel, carbon and tungsten, stainless steel, carbon and alluminiumalluminium to simulate beryllium behaviour to simulate beryllium behaviour

EFDA Task TW5 TSS SEA5.1EFDA Task TW5 TSS SEA5.1Dust mobilization and transport experiments in the STARDUST deviceDust mobilization and transport experiments in the STARDUST device

Feasibility studyFeasibility study (on going) (on going)

1.1. The toroidal shape can give precise indication The toroidal shape can give precise indication about the reduction of the velocity field (about the reduction of the velocity field (circular circular sectionsection) )

2. Scale rule -> 2. Scale rule -> 1/101/10 of of ITER major radius : ITER major radius : (0.62 m) and minor (0.62 m) and minor radius (0.2 m)radius (0.2 m)

3. 4 3. 4 through windowsthrough windows to to allow the allow the visualization and visualization and possible possible measurement of the measurement of the dust mobilization dust mobilization insideinside


Investigation on DiagnosticsInvestigation on Diagnostics (on (on going)going)

1. 1. CDD cameraCDD camera for dust visualization, and for dust visualization, and analysis ofanalysis of

the images (up to 8000 images/s) enable the the images (up to 8000 images/s) enable the qualitativequalitative assessment of the dust assessment of the dust concentration.concentration.

2. The light scattering method will be used if 2. The light scattering method will be used if the dust concentration is not such to stop the dust concentration is not such to stop the light beam.the light beam.


For 2006 experiments in STARDUST Velocity For 2006 experiments in STARDUST Velocity measurement is a key factormeasurement is a key factor

•Pressure trasducer will be Pressure trasducer will be adopted because hot wires have adopted because hot wires have a reduced range for maximum a reduced range for maximum velocity (maximum 80 m/s) and velocity (maximum 80 m/s) and signal delayed (~500 ms)signal delayed (~500 ms)

• The dimension of pressure The dimension of pressure trasducers does not trasducers does not disturb the velocity fielddisturb the velocity field

• Several points of Several points of measurement will be measurement will be foreseenforeseen


Scope of the task

• ValidationValidation of the simulation code CONSENCONSEN against the

cryogenic experimentscryogenic experiments carried on in the EVITAEVITA facility during 2005.

• 11 pre and post-test calculations11 pre and post-test calculations for steam and water entering the VV with the presence of incondensable gas (helium)

• The objectives of the tests were to determine the

water/steamwater/steam condensationcondensation phenomena on a

cryogenic platecryogenic plate inin presence of gaspresence of gas, to evaluate ice formation kinetics, heat transfer, total condensed water mass, cryogenic surface temperature and dynamic pressure and temperature of the container.

EFDA Task TW4 TSS SEA5.5 (CONSEN)EFDA Task TW4 TSS SEA5.5 (CONSEN)Validation of the computer codes and modelsValidation of the computer codes and models

Results

The constant valuesconstant values of the nitrogen heat transfernitrogen heat transfer coefficientcoefficient in the cooling tubes used in the simulations can be the cause of the differences.

EFDA Task TW4TSS SEA5.5 (CONSEN)EFDA Task TW4TSS SEA5.5 (CONSEN)

Validation of the computer codes and Validation of the computer codes and modelsmodels

Case 6.10 - VV temperature

0

50

100

150

200

250

300

0 80 160 240 320 400 480

time (s)

tem

per

atu

re (

°C)

CONSEN

EVITA

Case 6.10 - VV pressure

0.0E+00

1.0E+04

2.0E+04

3.0E+04

4.0E+04

5.0E+04

0 80 160 240 320 400 480

time (s)

pre

ssu

re (

Pa)

CONSEN

EVITA

Case 6.10 - Ice thickness and mass

0

1

2

3

0 100 200 300 400 500 600 700

time (s)

ice

thic

kn

ess

(mm

)

0.00

0.10

0.20

0.30

0.40

0.50ice m

ass (kg)

CONSEN ice thicknessCONSEN ice massEVITA ice mass

Case 6.10 - Wall temperature

0

40

80

120

160

0 80 160 240 320 400 480

time (s)

tem

per

atu

re (

°C)

CONSEN

EVITA

The ice ice formationformation is correctly correctly simulatedsimulated in all the tests with the exceptionexception of the test 6.516.51, in which more than one calculated output is far from the experimental one.

Power Power extractedextracted from the nitrogen cooling loop is in satisfactory satisfactory agreementagreement, in general, in the hot testshot tests while a larger discrepancydiscrepancy appears in the cold tests. cold tests.

Scope of the task

• ValidationValidation of the simulation code CONSENCONSEN against the

cryogenic experimentscryogenic experiments carried on in the EVITAEVITA facility during 2005.

• 7 post-test calculations7 post-test calculations for steam and water entering the VV with and without the presence of incondensable gas

• The process of ice formationice formation is the key point of the experimental campaign. Accordingly with the previous experiment the ice formation stops after a couple of minutes while in the CONSEN simulations the ice growth continues until the end of the transients.

• A series of teststests with the same initial conditionssame initial conditions

stoppedstopped at different timedifferent time have been performed to clarify this point.

EFDA Task TW5 TSS SEA5.5 (CONSEN)EFDA Task TW5 TSS SEA5.5 (CONSEN)Validation of the computer codes and modelsValidation of the computer codes and models

Results

The results obtained showed that the CONSEN CONSEN code simulated correctlycorrectly the growing of the ice massice mass on the cryogenic plate on the long termlong term (second EVITA point in the graphs), while in the short termshort term differencesdifferences of about 20%20% have been noted.

EFDA Task TW5 TSS SEA5.5 (CONSEN)EFDA Task TW5 TSS SEA5.5 (CONSEN)

Validation of the Validation of the

computer codes computer codes

and modelsand models

Scope of the task• Review and documentation of the past analysis

assumptions/parameters and results for 1. Ion Cyclotron Heating and Current Drive System,2. Electron Cyclotron Heating and Current Drive System,3. Neutral Beam Heating and Current Drive System,4. Diagnostics, and5. Test Blankets

• Reanalysis of the above systems, on the basis of the current design and operating information.

• Identification and analysis of potential improvements, for each of the above systems. The results of this sensitivity analysis will be documented to facilitate any future considerations for dose reduction strategies

EFDA Task TW5 TSS SEA2.1AEFDA Task TW5 TSS SEA2.1AUpdate of ALARA analyses for ITER Occupational Radiation ExposureUpdate of ALARA analyses for ITER Occupational Radiation Exposure

Past ORE Past ORE assessmentsassessments

ORE assessment 2003

ECH&CD8%

Diagnostics12%

Test Blankets3%

Margin35%

RH Equipment*8%

NBI (only cooling)4%

HC&WT*8%

Blankets4%

Divertor1%

VP&LDS2%

Tritum Plant0%

ICH&CD4%

TCWS (FW/BL+DV/LIM)

11%

Blankets

Divertor

TCWS (FW/BL+DV/LIM)

VP&LDS

Tritum Plant

ICH&CD

ECH&CD

Diagnostics

Test Blankets

RH Equipment*

HC&WT*

NBI (only cooling)

Margin

The contribution of the different sytems are referred to ITER plant limit, that is

500 mSv/y


ORE assessment 2002

ECH&CD12%

Diagnostics16%

Margin29%

ICH&CD4%

Tritum Plant0%

VP&LDS1%

Divertor1%

Blankets4%

HC&WT*8%

NBI (only cooling)3%

RH Equipment*8%

Test Blankets3%

TCWS (FW/BL+DV/LIM)

11%Blankets

Divertor

TCWS (FW/BL+DV/LIM)

VP&LDS

Tritum Plant

ICH&CD

ECH&CD

Diagnostics

Test Blankets

RH Equipment*

HC&WT*

NBI (only cooling)

Margin

Worker dose estimates for NB & LH heating & current drive systems

A preliminary ORE assessment of the ITER Neutral Beam and Lower Hybrid heating and current drive system has been performed, as it did not previously exist for these systems. Main assumptions for ORE:-NBI maintained by RH-VTL section in LH maintained in hot cell

System Work effort(p-h)

Dose rateSv/h

OREmSv/y

NBI&CD 267 10 8.1

LH&CD 183 1-10 1.2

ORE assessment 2005

HC&WT*8%

LH&CD0%

ICH&CD4%

Tritum Plant0%

VP&LDS2%

Divertor1%

Blankets4%

RH Equipment*8%

Test Blankets3%

Diagnostics12%

ECH&CD8%

NBI 2%

Margin37%

TCWS (FW/BL+DV/LIM)

11%Blankets

Divertor

TCWS (FW/BL+DV/LIM)

VP&LDS

Tritum Plant

ICH&CD

ECH&CD

Diagnostics

Test Blankets

RH Equipment*

HC&WT*

NBI

LH&CD

Margin


Issues of the task• ORE related to remote handling

Develop a software tool to assist the safety analysts in evaluating maintenance procedures and ORE values. Assess hands-on activities to be performed in the Equatorial Port number one (Eq#01) in assistance to the RH for maintenance of port plug, i.e.: the clearance of port cell from equipments located in front of the port, the unsealing of port plug and, vice-versa, the sealing of the port plug and the reinstallation of equipments located in port cell.

• ORE related to waste managementAssess maintenance activities on the Waste Treatment System where wastes originated in the ITER plant from the experimental and maintenance activities are collected and treated (such wastes do not include those highly activated and managed inside the Hot Cell Processing System).

EFDA Task TW4 TSS SEA2EFDA Task TW4 TSS SEA2In-depth assessment of ORE during RH and waste managementIn-depth assessment of ORE during RH and waste management

A view of the ORE_In_Rooms_Code


Main Results on ORE assessments• ORE related to remote handling

The total hands-on activities to be performed in assistance to the RH of port plug in Eq#01 require a total work effort of 472 p-h (118 p-h/y) and a collective worker dose of about 30 p-mSv (7.4 p-mSv/y). The highest contribution in terms of collective dose comes from the operations on the port plug flange (main flange unsealing/sealing, cooling pipes cutting/welding), with about 7 p-mSv (~1.8 p-mSv/y).

• ORE related to waste managementThe estimated collective annual dose relative to the Waste Treatment System is about 5 p-mSv/y.


Scope of the task

It is dedicated to provide activation data in support of ITER safety and design to cover, in due time, the needs arising from design modification and/or optimisation.

The analyses have been dedicated:

• to highlight the impact of the cobalt content into the Vacuum Vessel steels for waste management policy and

• to characterise the activation of the steel test tubes irradiated in OSIRIS reactor for ITER material release rate tests in CORELE-2 loop and PACTITER code validation

EFDA Task TW4 TSS SEA4.1EFDA Task TW4 TSS SEA4.1

Activation calculation for ITERActivation calculation for ITER

Material clearance

index vs. Co content

VV Rear Wall Outboard VVRWO - 316L(N)-IG

1.E-3

1.E-2

1.E-1

1.E+0

1.E+1

1.E+2

1.E+3

10 100 1000

Time after plant final shutdown [y]

Cle

aran

ce I

nd

ex

Co 0.01 wt%Co 0.05 wt%Co 0.15 wt%Co 0.25 wt%Clearable level

VV Rear Wall Outboard VVRWO - 316L(N)-IG

1.E-6

1.E-5

1.E-4

1.E-3

0.1 1 10

Time after plant final shutdown [y]

Con

tact

Dos

e R

ate

[Sv/

h]

Co 0.01 wt%Co 0.05 wt%Co 0.15 wt%Co 0.25 wt%100 microSv/h level

Material contact dose

vs. Co content



A neutronic model was set up and used in SCALENEA-1 to simulate the CORELE steel test tubes irradiation in OSIRIS reactor.Once estimated the neutron flux spectra, activation calculation were performed using the ANITA-2000 activation code.

Activity (Bq) for the 127 g tube Isotope Experimental measurements ENEA calculation

Co-60 1.13 E+07 9.61 E+06 Co-58 1.20 E+07 1.04 E+07 Mn-54 1.72 E+06 1.51 E+06 Fe-59 1.49 E+07 1.09 E+07 Cr-51 7.00 E+08 5.63 E+08

The comparison shows a good agreement between measured and calculated isotope activities : therefore the approach is suitable to evaluate the activation data needed by PACTITER code for ACP estimate



Scope of the task

• Validation of the activation code package ANITA-2000 against experimental vanadium alloys, nickel, copper, lithium orthosilicate, Eurofer-97 steel and tungsten activity data from the Karlsruhe Isocyclotron (KIZ).

• Validation of the activation code package ANITA-2000 against experimental photon and electron decay heat measurements from Fusion Neutron Generator FNG ENEA-Frascati for Molybdenum and Tantalum.


(ANITA-2000)(ANITA-2000)

Validation of the computer codes and modelsValidation of the computer codes and models

Isotope Experimental data (KIZ)

ANITA-2000 EAF-2003

Cr 51 1.21E+08 1.07E+08

Mn 54 7.27E+07 7.33E+07

Fe 59 1.20E+05 9.49E+04

Co 57 7.79E+04 7.15E+04

Co 58 8.47E+05 8.12E+05

Co 60 3.77E+03 2.44E+03

W 185 9.16E+06 6.49E+06

For all the KIZ materials analysed the ANITA-2000 results are in good agreement with the experimental ones (inside the experimental uncertainties)

Activity (Bq/kg) for Eurofer-97 (41 days cooling time)

Cooling time(s)

Experimental data

ANITA-2000 EAF-2003

631 1.76E-13 1.75E-13

4793 1.56E-13 1.56E-13

13132 1.28E-13 1.27E-13

67902 3.68E-14 3.50E-14

93701 2.10E-14 1.92E-14

Tantalum gamma decay heat (kW)

The calculated photon and electron decay heat are in good agreement with experimental data (up to 10% for Ta and 15% for Mo).

The ANITA-2000 and EASY-2003 calculations differ by less than 1%.

EFDA Task TW5 TSS SEA5.5 EFDA Task TW5 TSS SEA5.5 (ANITA-2000)(ANITA-2000)

Validation of the computer codes and modelsValidation of the computer codes and models

• Recycling is becoming more and more important in a world which is going to deal with energy and natural resources shortage.

• Present studies on recycling of slightly radioactive material show positive outcomes while at the same time problems of public acceptability still exist.

• Safety criteria have been defined, regulations and standards are going to be set in place in many countries, even though the need for harmonising clearance levels is still an issue.

Clearance levels (CLs) in [Bq/g]

Nu

clid

e

Be

lgiu

m

De

nm

ark

(°)

Ge

rma

ny

Gre

ece

Ita

ly (

*)

Lu

xem

bu

rg

Ne

the

rlan

ds

Fin

lan

d

Sw

ede

n

UK

EC

RP

122

241Am 1.0E-01 5.0E-02 1.0E-01 5.0E-02 1.0E+00 1.0E-01 1.0E-01 4.0E-01 1.0E-01 239Pu 1.0E-01 4.0E-02 1.0E-01 4.0E-02 1.0E+00 1.0E-01 1.0E-01 4.0E-01 1.0E-01 137Cs 1.0E+00 5.0E-01 1.0E+00 1.0E+00 5.0E-01 1.0E+01 1.0E+00 5.0E-01 4.0E-01 1.0E+00 90Sr 1.0E+00 2.0E+00 1.0E+00 1.0E+00 2.0E+00 1.0E+02 1.0E+00 5.0E-01 4.0E-01 1.0E+00 60Co 1.0E-01 1.0E-01 1.0E-01 1.0E+00 1.0E-01 1.0E+00 1.0E+00 5.0E-01 4.0E-01 1.0E-01 65Zn 1.0E+00 5.0E-01 1.0E+00 5.0E-01 1.0E+01 1.0E+00 5.0E-01 4.0E-01 1.0E+00 51Cr 1.0E+01 1.0E+02 1.0E+01 1.0E+02 1.0E+03 1.0E+01 5.0E-01 4.0E-01 1.0E+01 3H 1.0E+02 1.0E+03 1.0E+03 1.0E+00 1.0E+03 1.0E+06 1.0E+01 5.0E-01 4.0E-01 1.0E+02

238U 1.0E+00 5.0E-01 9.0E-03 1.0E+00 1.0E+00 1.0E-01 1.0E-01 1.11E+01 1.0E+00 232Th 1.0E-02 5.0E+00 2.0E-02 1.0E-02 3.0E-02 1.0E+00 1.0E-01 1.0E-01 2.59E+00 1.0E-02 228Th 1.0E-01 5.0E-01 1.0E-01 1.0E-01 1.0E-01 1.0E+00 1.0E-01 1.0E-01 2.59E+00 1.0E-01

228Ra+ 1.0E-02 1.0E+00 7.0E-02 1.0E-02 7.0E-02 1.0E+00 1.0E+01 5.0E-01 3.70E-01 1.0E-02 226Ra+ 1.0E-02 5.0E-01 3.0E-02 1.0E-02 3.0E-02 1.0E+00 1.0E-01 1.0E-01 3.70E-01 1.0E-02 210Pb 1.0E-02 5.0E+00 2.0E-02 1.0E-02 4.0E-02 1.0E+02 1.0E+01 5.0E-01 7.40E-01 1.0E-02 210Po 1.0E-02 5.0E+00 4.0E-02 1.0E-02 4.0E-02 1.0E+02 1.0E-01 1.0E-01 3.70E-01 1.0E-02

(°) for natural radionculides (*) clearance levels proposed for the decommissioning of Caorso NPP

Table from EC RP 134: Evaluation of the application of the concepts of exemption and clearance for practices according to title III of Council Directive 96/29/Euratom of 13 May 1996 in EU Member States – 2003.

Case of tritium (harmonisation of CLs): clearance level from 0.4 Bq/g in UK up to 1.0E+6 Bq/g in the Netherlands

EFDA Task TW4-TSW-001 D2-D3EFDA Task TW4-TSW-001 D2-D3

Watching brief and waste managementWatching brief and waste management

• The experience of decommissioning of an entire generation of nuclear facilities will be exploited by future fusion industry, (i.e. for recycling, reuse or disposal).

• The real waste management problem will be relative to the in-vessel components (IVCs) similarly as the management of spent fuel is the “problem” in fission.

• The fusion industry would have the advantage of being able to use activated metal, as it would be employed in a controlled environment, where radiation fields will be monitored.

• It seems more important to demonstrate the feasibility of IVCs recycling from the technical point of view, rather than try to perform an economic assessment with the present-day terms in mind.

• It would be greatly more important to concentrate the future activities on:1. the study of the fusion material and equipment cycle and; 2. on the regulatory framework, within which recycling of fusion material could be performed.

Time distribution for generation of slightly radioactive solid material from USA power reactor decommissioning

EFDA Task TW4-TSW-001 D2-D3EFDA Task TW4-TSW-001 D2-D3

Watching brief and waste managementWatching brief and waste management

Documents

Index: Status report ENEA tasks (Dec 2005) EFDA Task TW4 TSS SEA5.1............................slides 2,3,4 EFDA Task TW5 TSS SEA5.1............................slides