Final Meeting

TW5-TSW-001

Deliverable 7

SCK•CEN, L. OomsCulham, October 23–24, 2006

Goals of the study

Definition of the material cycle paths

Strategy of the closed material cycle:Important benefits:

•Reduction of waste volume

•Savings on valuable materials

Other aspects:•Technical feasibility

•Material availibility

•Energy demand and Economical aspects

•Environmental issues and public opinion

Materials and their properties

Component Blanket HTS LTS VV TF COIL Div. struc Div. Tiles Total

Eurofer 1.74E+06 1.27E+06 7.02E+05 - - - - 3.71E+06

316SS - - - 7.09E+06 - 1.23E+06 - 8.32E+06

Others - - - - 4.48E+07 - - 4.48E+07

W 5.45E+04 - - - - - 1.68E+05 2.23E+05

LiPb 6.19E+06 - - - - - - 6.19E+06

WC - - 4.57E+06 - - - - 4.57E+06

B - - - 1.85E+05 - - - 1.85E+05

He 1.66E+06 1.27E+06 - - - 1.23E+06 - 4.16E+06

H2O - - 1.76E+06 4.27E+06 - - - 6.03E+06

Total 9.64E+06 2.55E+06 7.02E+06 1.16E+07 4.48E+07 2.46E+06 1.68E+05 7.82E+07

Materials used in the PPCS Model AB and their weights (kg)

2.5 years

5 years

Life time

Materials and their properties

Component Blanket HTS LTS VV TF COIL Divertor

Eurofer 18.0% 50.0% 10.0% - - -

316SS - - - 61.4% - 46.8%

Others - - - - 100.0% -

W 0.6% - - - - 6.4%

LiPb 64.2% - - - - -

WC - - 65.0% - - -

B - - - 1.6% - -

He 17.2% 50.0% - - - 46.8%

H2O - - 25.0% 37.0% - -

Percentage of material in each component

2.5 years

5 years

Life time

Materials and their properties

Refractory materials: W & WC

Breeder material: 17Li-83Pb

Coolants: He & H20

Structural materials:•Special metal: Eurofer•Stainless steel 316SS

Other materials:•Boron: boronizing the VV•Materials of the coils

Materials and their properties

Refractory materials: W & WC

Coating technologies:

•Vacuum/Atmospheric Plasma Spraying

•Chemical/Physical Vapour Disposition

•Roll cladding

•W-coatings on Graphitic substrates

Joining technologies:

•Brazing

•Electron Beam Welding

•Diffusion bonding/Hot Isostatic Pressing

•Active metal casting

Non destructive analysis:

•Radiography

•Ultrasonic

•Thermography

•Hot Helium leak tests

Materials and their properties

Refractory materials: W & WC

Recycling:

•Melting point: 3370°C => excluded

•Separation of W and base material by melting

•Obtaining W powder is the goal for recycling:

•Oxidation of W metal at 700°-800°C => volatile W-oxides (to be trapped and collected in filters). Disadvantages:

• high temperature + O2 = explosion risks, •very slow processus

•Chemical dissolvement => very resistant material only a mixture of concentrated HF and HNO3 would have results

•Crushing/grinding of Tungsten to powder => T is one of the hardest products (nearby diamond) and therefore hard to employ

Materials and their properties

Fabrication process of Tungsten

Materials and their properties

Structural materials

Melting is an option for these materials since this is the basic step in their fabrication.

Stainless steel 316SS Eurofer

But necessary? Other less drastic processes e.g. annealing, for repair of the irradiation damage (embrittlement, formation of He…)

Breeder material: 17Li-83Pb => not regarded

Coolants: He & H20 => no tendency to activate, but watch out for impurities and erosion of the cooling tubes! Therefore filtration or chemical purification will be necessary.

Other materials => not regarded :• Boron• Materials of the coils

Materials and their properties

Dose rate of the materials

component 5 years 10 years 50 years 100 years

TF Coil 1.1E-05 5.8E-06 1.2E-07 9.1E-08

VV 0.173 0.088 5.0E-04 1.8E-05

LTS 2.5 1.3 0.011 5.3E-04

HTS 13.6 7.0 0.04 2.3E-04

blanket manifold 16.2 8.1 0.042 3.3E-04

blanket breeder 1 0.7 0.3 0.005 4.0E-04

blanket breeder 2 6.7 0.88 0.015 0.003

blanket FW 158.8 14.8 0.037 0.001

blanket armour 9.0 4.2 0.044 0.007

divertor 45.1 19.9 0.1 0.001

divertor tiles 7.3 3.5 0.030 0.003

  Clearance (CI < 1?)

  hands on recycling

  Shielded recycling

  Remote handling

Dose rate (Sv/h)

2.5 years

5 years

Life time

The dose rate of the materials remains an important parameter

in the recycling strategy.

• For life time components, one can apply deferred recycling

(decay can be a solution to apply (conditional) clearance on

these materials) e.g. TF-coil, Vacuum Vessel, LTS

• In Vessel components demand a remote handling system,

therefore immediate recycling (after interim storage) should be

applied.

Conclusions/ideas for discussion

• Stainless steel and Eurofer can be melted, but maybe a less

drastic processes can be applied for reuse of materials

• The feasibility to recycle Refractory materials (W and WC)

is still to be studied, although some options are noted.

• Coolants: He & H20 => watch out for impurities and

erosion of the cooling tubes!

• LiPb: re-utilisation is described in a paper (R. Pampin)

Conclusions/ideas for discussion

Material treatment

Report:

Categorisation based on Material recycling paths

TW5-TSW-001 D7

Draft in edit, final report end of November 2006

Final Meeting

TW5-TSW-001

Deliverable 8a

SCK•CEN, L. OomsCulham, October 23–24, 2006

Definition of the R&D needs

R&D needs

Different areas

Component handling

Design for Recycling

Material properties

R&D needs

Component handling

•Hot cell environment

•Shielded environment

•Hands on environment

•Interim storage

•Internal contamination hazards

R&D needs

Design for Recycling

•Maximum recuperation of structural materials

•Mechanical attachment techniques

•Specification on impurities

R&D needs

Material properties• Recycling possibilities of the “exotic” materials to be

studied in detail; e.g. LiPb, W, WC, Be

• Separation methods for components based on design.

• Build up of activation products when reuse is applied

Others• Removal of T in all necessary processes

• Waste fabrication during recycling, first estimate

Report:

Definition of the R&D needs

TW5-TSW-001 D8

Draft in edit, final report end of december 2006