Proficiency Test: Non-destructive Assay of 220 liters Waste Drums by Gamma Assay Systems (an ENTRAP initiative)

Transcription

1 Proficiency Test: Non-destructive Assay of 220 liters Waste Drums by Gamma Assay Systems (an ENTRAP initiative) Leo van Velzen IAEA LABONET Annual meeting December 2013 Vienna Austria

2 Content ~ Introduction ~ ENTRAP ~ Principle Proficiency test ~ Basic design 220 ltr drums ~ Engineering 200 ltr drums ~ Modeling radioactivity content ~ Conclusions 2

3 ENTRAP ~ Acronym for: European NeTwork for the Quality Checking of RAdioactive Waste Packages ~ Established in 1992 on the initiative of the European Commission ~ Scope: Within the framework of regulatory checking of radioactive waste packages to facilitate collaboration on research and development in the field of testing and laboratory procedures. 3

4 ENTRAP ~ Working/task groups: Non-destructive characterization Destructive characterization Quality control Quality checking of ILW and LLW 4

5 ENTRAP ~ Members: CEA (France) Ciemat (Spain) ENEA (Italy) ENRESA (Spain) Forschungszentrum Jülich (Germany) Forschungszentrum Karlsruhe (Germany) JRC-Ispra (Italy) NRG (Netherlands) Nuclear Engineering Seibersdorf (Austria) Nuclear Research Institute Rez (Czech Republic) SCK-CEN (Belgium) Technical University München-RCM (Germany) VTT (Finland) 5

6 Principle Proficiency test ~ Proficiency test restricted to 220 liters drums; ~ No (international) transports of 220 liters drums; ~ Every participant an own set of reference drums ~ Reference drums has to fulfill to all requirements of participants inside the EU, fits for purpose and must be reusable and should contain only reference sources; ~ The costs for the empty drum: Once; ~ The costs for the reference sources and participation per proficiency test has to be reasonable. 6

7 Principle Proficiency test Specifications of set of reference drums External dimensions Belgium 220 ltr standard Average height [mm] 856 ± Average diameter [mm] 606 ± Internal dimensions Average height [mm] 835 ± Average diameter [mm] 573 ± Drum material steel steel Average thickness [mm] 1.1 ± Average weight [kg] 17 ±

8 Principle Proficiency test Specifications of set of reference drums (continued) Weight Average waste density compacted [kg/m 3 ] Average waste density raw [kg/m 3 ] Solid and not toxic X Reference sources and health physics Gamma dose rate [μsv/h] > 5 Total activity [Bq] 3.7E11 1E8 < 5E6 Reference nuclides K-40, Co-57, Co-60, I-131, Cs-192 Eu-152, NORM Solid (no gaseous or liquid) Eu-152 Co-60 X 8

9 Principle Proficiency test Specifications of set of reference drums (continued) Financial aspects As cost effectively as possible, especially for the first transport and for the eventual follow-up proficiency test. 9

10 Basic design 220 ltr drums Specifications 200l drum 7 Tubes Diameter ± 12 mm Half discs: Height 50 mm, Max weight 25 kg Material 1: Density ± 960 kg/m 3 Material 2: Density ± 1420 kg/m 3 10

11 Basic design 220 ltr drums Specifications Material 1 Material 2 Schematic presentation of possible matrix geometries 11

12 Basic design 220 ltr drums Specifications ~ 6 reference source positions; ~ rotated 60 degrees ~ simulating an uniform distributed radioactivity. 12

13 Engineering 220 ltr drums Specifications ~ Drums should be fit for vertical and horizontal rotation. Risk horizontal rotation might be not continuous and can damage reference sources; ~ The non-radioactive drums including reference sources should be easily to transport (UN2910); ~ Hoisting; ~ Work conditions during dismantling and mounting (e.g. max weight to be handled by man); 13

14 Engineering 220 ltr drums Specifications ~ The applied inactive materials have to be in platters: ~ Disadvantage: machining is expensive; ~ Advantage: creates opportunity of mixing the non-radioactive matrices; ~ Reusable, different configurations of applied nonradioactive and radioactive reference materials; ~ Each line source (800 mm) exists of 3 smaller line sources; 14

15 Engineering 220 ltr drums ~ Due to new design of line sources: Participants own reference sources are limited applicable; ~ Reference drums without radioactive reference sources: transport by road. ~ Reference drums containing radioactive reference sources: transport by air carrier. ~ Transport crates: ~ Max dimensions of a standard pallet with a height 800 mm; ~ In principle not reusable. 15

16 Modeling Shielding properties modeled by VISIPLAN 3D (SCK-CEN) Proficiency test design: Side view Top view 16

17 Modeling Transport design 3D View Side view Detail C C B Detail B A Detail A 17

18 Modeling results HDPE (960 kg/m 3 ) Transport design: Lateral view Front view 18

19 Modeling results HDPE (960 kg/m 3 ) Transport design: Top view Bottom view 19

20 Conclusions Design: ~ Proficiency test 6 positions simulating uniform distributed radioactive content; ~ Transport 7 positions in order to fulfill UN2910; ~ Special constructions to apply horizontal and vertical rotation; ~ Two different non-radioactive materials HDPE and POM; ~ Line sources: ~ 5 * Length 800 mm, nuclide Eu-152 (500 kbq); ~ 1 * Length 800 mm, nuclide Eu-152 (500 kbq) and Co-60 (1.8 MBq). 20

21 Thank you for your attention 21