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Clearance and disposal of ITER radioactive waste components
Fusion Engineering and Design 58 – 59 (2001) 945– 947 www.elsevier.com/locate/fusengdes
Clearance and disposal of ITER radioactive waste components K. Brode´n *, E. Eriksson, M. Lindberg, G. Olsson Studs6ik RadWaste AB, SE-611 82 Nyko¨ping, Sweden
Abstract Future fusion reactors will generate radioactive material. In the present paper results from studies on radioactive material from two different International Thermonuclear Experimental Reactor (ITER) designs are presented. Results on quantities of radioactive materials, clearance possibilities and waste management are given for the 1998 ITER design. Preliminary results on quantities of radioactive materials and clearance are also given for the Fusion Energy Advanced Tokamak, ITER-FEAT. © 2001 Elsevier Science B.V. All rights reserved. Keywords: Radioactive waste components; Clearance; Fusion Energy Advanced Tokamak
1. Introduction Future fusion power plants and the International Thermonuclear Experimental Reactor (ITER), will produce radioactive materials due to neutron activation and tritium contamination. For several years studies on management of such material have been performed at Studsvik in Sweden. Results from a study on possibilities for disposal of ITER waste in three European countries have e.g. been reported earlier [1]. In the present paper updated results from this study are given. The study was based on principles for waste management of the 1998 ITER design in
* Corresponding author. Tel.: + 46-155-221502; fax: +46155-263025. E-mail address: [email protected] (K. Brode´n).
Volume V of the ITER Non-Site Specific Safety Report (NSSR-2) [2] and detailed radiological characteristics and waste amount information in the ITER Waste Streams and Characteristics Data Book (WSCDB) [3]. Preliminary results from an on-going waste study for the Fusion Energy Advanced Tokamak (ITER-FEAT) design are also given [4]. The study is based on component data from the ITER design teams in Garching and Naka and on input activation data from ENEA in Italy.
2. Radioactive materials The production of radioactive materials from operation and decommissioning of a fusion reactor depends both on the reactor design and the operational conditions. In total, about 83 000 ton-
0920-3796/01/$ - see front matter © 2001 Elsevier Science B.V. All rights reserved. PII: S 0 9 2 0 - 3 7 9 6 ( 0 1 ) 0 0 2 2 8 - 9
K. Brode´ n et al. / Fusion Engineering and Design 58–59 (2001) 945–947
946
nes of radioactive components will be generated from the 1998 ITER design during different operation and decommissioning phases [3]. About 3% will be generated during the Basic Performance Phase, 4% during the Transition Phase and 4% during the Extended Performance Phase. Considerably more will be generated during decommissioning. The decommissioning starts with the removal of highly activated in-vessel components in Decommissioning Phase 1. During this phase about 18% of the total amount of radioactive components will be generated. The first decommissioning phase is followed by a decay period, Decommissioning Phase 2, and finished with the dismantling of the vacuum vessel and peripheral components in Decommissioning Phase 3. About 71% of the total amount of radioactive components will be generated during Decommissioning Phase 3. Preliminary results from analysis of radioactive materials from the much smaller ITER-FEAT indicate that the total weight of the material will be about 32 000 tonnes (see Table 1). However neither the divertor weight nor the weights of components from replacement have been included in the sum.
3. Clearance The large amounts of mainly metallic materials from the decommissioning of a fusion reactor makes recycling an attractive option. Clearance possibilities for radioactive materials from the 1998 ITER design were estimated based on the levels in IAEA’s interim report TECDOC 855 for unconditional clearance of solid material [5] and the Commission of European Communities (CEC) recommendations in Radiation Protection 89 for recycling of metals from the dismantling of nuclear installations [6]. The result from the estimation indicates that the clearance quantity is in the range 38–75 weight-% of the total ITERFDR material quantity, depending on clearance criteria, decay time and specific activity assumptions. Preliminary results on clearance possibilities for the ITER-FEAT components indicate that up to about 84% of the total material possibly could be cleared after 100 years of interim storage if the IAEA clearance levels are applied (see Table 1). However, this figure will be somewhat reduced when divertor and in-vessel replacement components are included. The mid-plane activity after 100 years of decay will reach clearance levels in
Table 1 Preliminary ITER-FEAT component weights (the divertor weight has so far not been estimated) and preliminary results on clearance possibilities after 100 years of interim storage Component
Weight (tonnes)
Clearable according to IAEA levels?
Clearable quantities (tonnes)
TF coil inboard TF coil outboard PF coils Correction coils Central solenoid Vacuum vessel Blanket system Fuelling Cryostat Cooling water system Thermal shields Diagnostics Biological shield Total, rounded
2200 2900 2000 50 700 5100 1600 70 4100 4600 900 900 6700 32 000
Partlya Yes Yes Yes Yes Partlyb No No Yes Yes No Yes Yes
2000 2900 2000 50 700 3200 0 0 4100 4600 0 900 6700 27 000
a b
Provided the conductor could be separated from the remaining material. If individual separation of rear outboard zones of the vacuum vessel wall is possible.
K. Brode´ n et al. / Fusion Engineering and Design 58–59 (2001) 945–947
the TF coil rear zones on the inboard side and in the vacuum vessel rear zones on the outboard side.
947
for ITER-FEAT than for the 1998 ITER design, mainly because ITER-FEAT is smaller but also due to slightly less activation of the ITER-FEAT components.
4. Waste management References Materials from the 1998 ITER design not passing the clearance limits were studied for disposal possibilities in the French and Swedish existing repositories Centre de Stockage de l’Aube (CSA) [7] and SFR [8], respectively, for short-lived low and intermediate level waste, and for acceptance as Category 2 waste according to Italian criteria [9]. Components not passing the CSA/SFR-criteria or the Category 2 criteria require deep geological disposal in the three countries. The major part of the components with activity concentration exceeding the clearance levels may be disposed of in a surface repository (CSA) or shallow geological repository (SFR). The quantity is in the range 11– 47% of the total weight of the radioactive components from the 1998 ITER design, depending on the clearance possibilities. The corresponding repository volume required for waste in waste containers is in the range 4000–20 000 m3. This can be compared to a repository volume less than 6000 m3 in a deep geological repository required for the most activated ITER-FDR components (about 14 weight-% of the ITER-FDR components) [10]. The repository volumes required in different types of repositories have so far not been calculated for ITER-FEAT. However, the total repository volumes required and also the waste amounts requiring deep disposal are expected to be lower
[1] K. Brode´ n, M. Lindberg, G. Olsson, Possibilities for disposal of ITER waste in three European countries, Fusion Engineering and Design, 51 – 52 (2000) 467 –470. [2] International Thermonuclear Experimental, ITER NonSite Specific Safety Report (NSSR-2), Volume V, Waste management and decommissioning, December 18, 1997. [3] A.V. Kashirski, ITER Waste Streams and Characteristics Data Book (WSCDB), Version 2.1, ITER Joint Central Team, December 19, 1997. [4] K. Brode´ n, E. Eriksson, M. Lindberg, G. Olsson, Plan for the realisation of the rask Quantification of waste for ITER-FEAT (D458), Studsvik RadWaste AB, Sweden, 2000, Technical Note RW-00/10. [5] IAEA, Clearance levels for radio-nuclides in solid materials, Application of exemption principles, Interim report for comment, IAEA TECDOC-855, Vienna, January, 1996. [6] Commission of the European Communities, Recommended radiological protection criteria for the recycling of metals from the dismantling of nuclear installations, CEC Radiation Protection 89, Luxembourg, 1998. [7] T. Andre, Experience of an engineering company in shallow land disposal of L/ILW. Proceedings for Planning and operation of low level waste disposal facilities, Vienna, June 17 – 21, 1996, IAEA-SM-341/73. [8] Swedish Nuclear Fuel and Waste Management Co, Final safety report for SFR 1 (In Swedish). Svensk Ka¨ rnbra¨ nslehantering AB, 1987. [9] ENEA-DISP, Technical Guide No 26, Radioactive waste management, ENEA, May, 1988. [10] G. Olsson, K. Brode´ n, Quantification of ITER waste volumes for final disposal based on practices and principles in France, Italy and Sweden. Final report. Studsvik RadWaste AB, Sweden 1999. Technical Note RW-99/81.
Clearance and disposal of ITER radioactive waste components K. Brode´n *, E. Eriksson, M. Lindberg, G. Olsson Studs6ik RadWaste AB, SE-611 82 Nyko¨ping, Sweden
Abstract Future fusion reactors will generate radioactive material. In the present paper results from studies on radioactive material from two different International Thermonuclear Experimental Reactor (ITER) designs are presented. Results on quantities of radioactive materials, clearance possibilities and waste management are given for the 1998 ITER design. Preliminary results on quantities of radioactive materials and clearance are also given for the Fusion Energy Advanced Tokamak, ITER-FEAT. © 2001 Elsevier Science B.V. All rights reserved. Keywords: Radioactive waste components; Clearance; Fusion Energy Advanced Tokamak
1. Introduction Future fusion power plants and the International Thermonuclear Experimental Reactor (ITER), will produce radioactive materials due to neutron activation and tritium contamination. For several years studies on management of such material have been performed at Studsvik in Sweden. Results from a study on possibilities for disposal of ITER waste in three European countries have e.g. been reported earlier [1]. In the present paper updated results from this study are given. The study was based on principles for waste management of the 1998 ITER design in
* Corresponding author. Tel.: + 46-155-221502; fax: +46155-263025. E-mail address: [email protected] (K. Brode´n).
Volume V of the ITER Non-Site Specific Safety Report (NSSR-2) [2] and detailed radiological characteristics and waste amount information in the ITER Waste Streams and Characteristics Data Book (WSCDB) [3]. Preliminary results from an on-going waste study for the Fusion Energy Advanced Tokamak (ITER-FEAT) design are also given [4]. The study is based on component data from the ITER design teams in Garching and Naka and on input activation data from ENEA in Italy.
2. Radioactive materials The production of radioactive materials from operation and decommissioning of a fusion reactor depends both on the reactor design and the operational conditions. In total, about 83 000 ton-
0920-3796/01/$ - see front matter © 2001 Elsevier Science B.V. All rights reserved. PII: S 0 9 2 0 - 3 7 9 6 ( 0 1 ) 0 0 2 2 8 - 9
K. Brode´ n et al. / Fusion Engineering and Design 58–59 (2001) 945–947
946
nes of radioactive components will be generated from the 1998 ITER design during different operation and decommissioning phases [3]. About 3% will be generated during the Basic Performance Phase, 4% during the Transition Phase and 4% during the Extended Performance Phase. Considerably more will be generated during decommissioning. The decommissioning starts with the removal of highly activated in-vessel components in Decommissioning Phase 1. During this phase about 18% of the total amount of radioactive components will be generated. The first decommissioning phase is followed by a decay period, Decommissioning Phase 2, and finished with the dismantling of the vacuum vessel and peripheral components in Decommissioning Phase 3. About 71% of the total amount of radioactive components will be generated during Decommissioning Phase 3. Preliminary results from analysis of radioactive materials from the much smaller ITER-FEAT indicate that the total weight of the material will be about 32 000 tonnes (see Table 1). However neither the divertor weight nor the weights of components from replacement have been included in the sum.
3. Clearance The large amounts of mainly metallic materials from the decommissioning of a fusion reactor makes recycling an attractive option. Clearance possibilities for radioactive materials from the 1998 ITER design were estimated based on the levels in IAEA’s interim report TECDOC 855 for unconditional clearance of solid material [5] and the Commission of European Communities (CEC) recommendations in Radiation Protection 89 for recycling of metals from the dismantling of nuclear installations [6]. The result from the estimation indicates that the clearance quantity is in the range 38–75 weight-% of the total ITERFDR material quantity, depending on clearance criteria, decay time and specific activity assumptions. Preliminary results on clearance possibilities for the ITER-FEAT components indicate that up to about 84% of the total material possibly could be cleared after 100 years of interim storage if the IAEA clearance levels are applied (see Table 1). However, this figure will be somewhat reduced when divertor and in-vessel replacement components are included. The mid-plane activity after 100 years of decay will reach clearance levels in
Table 1 Preliminary ITER-FEAT component weights (the divertor weight has so far not been estimated) and preliminary results on clearance possibilities after 100 years of interim storage Component
Weight (tonnes)
Clearable according to IAEA levels?
Clearable quantities (tonnes)
TF coil inboard TF coil outboard PF coils Correction coils Central solenoid Vacuum vessel Blanket system Fuelling Cryostat Cooling water system Thermal shields Diagnostics Biological shield Total, rounded
2200 2900 2000 50 700 5100 1600 70 4100 4600 900 900 6700 32 000
Partlya Yes Yes Yes Yes Partlyb No No Yes Yes No Yes Yes
2000 2900 2000 50 700 3200 0 0 4100 4600 0 900 6700 27 000
a b
Provided the conductor could be separated from the remaining material. If individual separation of rear outboard zones of the vacuum vessel wall is possible.
K. Brode´ n et al. / Fusion Engineering and Design 58–59 (2001) 945–947
the TF coil rear zones on the inboard side and in the vacuum vessel rear zones on the outboard side.
947
for ITER-FEAT than for the 1998 ITER design, mainly because ITER-FEAT is smaller but also due to slightly less activation of the ITER-FEAT components.
4. Waste management References Materials from the 1998 ITER design not passing the clearance limits were studied for disposal possibilities in the French and Swedish existing repositories Centre de Stockage de l’Aube (CSA) [7] and SFR [8], respectively, for short-lived low and intermediate level waste, and for acceptance as Category 2 waste according to Italian criteria [9]. Components not passing the CSA/SFR-criteria or the Category 2 criteria require deep geological disposal in the three countries. The major part of the components with activity concentration exceeding the clearance levels may be disposed of in a surface repository (CSA) or shallow geological repository (SFR). The quantity is in the range 11– 47% of the total weight of the radioactive components from the 1998 ITER design, depending on the clearance possibilities. The corresponding repository volume required for waste in waste containers is in the range 4000–20 000 m3. This can be compared to a repository volume less than 6000 m3 in a deep geological repository required for the most activated ITER-FDR components (about 14 weight-% of the ITER-FDR components) [10]. The repository volumes required in different types of repositories have so far not been calculated for ITER-FEAT. However, the total repository volumes required and also the waste amounts requiring deep disposal are expected to be lower
[1] K. Brode´ n, M. Lindberg, G. Olsson, Possibilities for disposal of ITER waste in three European countries, Fusion Engineering and Design, 51 – 52 (2000) 467 –470. [2] International Thermonuclear Experimental, ITER NonSite Specific Safety Report (NSSR-2), Volume V, Waste management and decommissioning, December 18, 1997. [3] A.V. Kashirski, ITER Waste Streams and Characteristics Data Book (WSCDB), Version 2.1, ITER Joint Central Team, December 19, 1997. [4] K. Brode´ n, E. Eriksson, M. Lindberg, G. Olsson, Plan for the realisation of the rask Quantification of waste for ITER-FEAT (D458), Studsvik RadWaste AB, Sweden, 2000, Technical Note RW-00/10. [5] IAEA, Clearance levels for radio-nuclides in solid materials, Application of exemption principles, Interim report for comment, IAEA TECDOC-855, Vienna, January, 1996. [6] Commission of the European Communities, Recommended radiological protection criteria for the recycling of metals from the dismantling of nuclear installations, CEC Radiation Protection 89, Luxembourg, 1998. [7] T. Andre, Experience of an engineering company in shallow land disposal of L/ILW. Proceedings for Planning and operation of low level waste disposal facilities, Vienna, June 17 – 21, 1996, IAEA-SM-341/73. [8] Swedish Nuclear Fuel and Waste Management Co, Final safety report for SFR 1 (In Swedish). Svensk Ka¨ rnbra¨ nslehantering AB, 1987. [9] ENEA-DISP, Technical Guide No 26, Radioactive waste management, ENEA, May, 1988. [10] G. Olsson, K. Brode´ n, Quantification of ITER waste volumes for final disposal based on practices and principles in France, Italy and Sweden. Final report. Studsvik RadWaste AB, Sweden 1999. Technical Note RW-99/81.