Innovative gas and outgassing analysis and monitoring

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1 Innovative gas and outgassing analysis and monitoring Guillaume Genoud - guillaume.genoud@vtt.fi VTT Technical Research Centre of Finland Ltd Environmental Metrology This project has received funding from the Euratom research and training programme under grant agreement No

2 Participants Guillaume Genoud, Johannes Lehmuskoski, Teemu Kärkelä Pierre Trabuc, Lionel Boucher Antonietta Rizzo Corrado Rizzato Holger Tietze-Jaensch

3 Laser spectroscopy extensively used in emission and environmental monitoring

4 Can the same methods be applied to the monitoring of radioactive gaseous emissions?

5 Conventional techniques E. g. Liquid scintillation counting New alternative? require large amount of sample long acquisition time to achieve good sensitivity sample preparation required

6 6 Principles of laser spectroscopy for molecular detection

7 Molecular vibration modes Water Methane

8 Absorption spectrum of CO 2 isotopes 12 CO 2 13 CO 2 12 C 16 O 18 O 14 CO 2

9 Basics of laser spectroscopy Beer-Lambert law: I out = I in e -σln

10 Cavity ring-down spectroscopy

11 Compact instrumentation Footprint: 45 x 60 cm

12 Example: C-14 detection Experimental results

13 CO 2 vs 14 CO 2 spectra 16 O 13 C 18 O 16 O 12 C 16 O 16 O 13 C 16 O 14 C/C=1 ppb

14 Absorption spectrum with 14 CO 2 peak 13 CO 2 14 CO 2 G. Genoud et al., Radiocarbon Dioxide detection based on Cavity Ring-Down Spectroscopy and a Quantum Cascade Laser, Opt. Lett. 40, 1342 (2015)

15 50 ppt detection limit 14 C/C= 50 ppt 5 kbq/m 3 in air 400 ppm of CO 2 in air 2 Bq/m 3 after extraction of CO 2 from air G. Genoud et al., Radiocarbon Dioxide detection based on Cavity Ring-Down Spectroscopy and a Quantum Cascade Laser, Opt. Lett. 40, 1342 (2015)

16 10 sec acquisition time G. Genoud et al., Radiocarbon Dioxide detection based on Cavity Ring-Down Spectroscopy and a Quantum Cascade Laser, Opt. Lett. 40, 1342 (2015)

17 Tritiated water detection with CRDS C. Bray et al., Nucl. Instr. Meth. Phys. Res. A 789, 43 (2015). 17

18 Tritiated water detection with CRDS C. Bray et al., Nucl. Instr. Meth. Phys. Res. A 789, 43 (2015). 18

19 Key features of CRDS High sensitivity Fast acquisition rate Ideal Real-time, for waste outgasing on-site characterisation measurements? Compact size

20 Why CRDS for waste outgasing monitoring? Long-lived radioisotopes, challenging to detect CRDS has high sensitivity ideal for detection of small leaks Can differentiate molecular forms On-line on-site monitoring capabilities Continuous automatic monitoring in waste repositories 20

21 21 CRDS in CHANCE

22 WP5 objective Advance the use of Cavity Ring-Down Spectroscopy (CRDS) as an innovative technique to characterize outgassing of radioactive waste 14 CO 2 14 CH 4 HTO H 36 Cl H 36 Cl Develop completely new CRDS instrument C-14 Apply the CRDS technique for C-14 outgasing studies

23 WP5 structure Task 5.1: Development of H 36 Cl measurement Novel CRDS instrument for H 36 Cl detection This will be the first time that CRDS is used to detect this molecule highly relevant in the case of outgassing from graphite waste. Task 5.2: Investigation of the release behaviour of 14 C using CRDS CRDS used for the first time to provide information about the C14 release kinetics, including speciation between methane and carbon dioxide An already developed instrument will be used for these studies Comparison and validation with well-established techniques such as liquid scintillation counting using reference samples or data Major step forward in the development of the use of CRDS to detect radioactive gas waste outgasing.

24 Task 5.1: CRDS for H 36 Cl Demonstrate the efficiency of outgassing H36Cl measurement with the use of CRDS Specification and development of a CRDS instrument dedicated to 36Cl measurement Validation of the transitions of rotation/vibration of this molecule H 36 Cl Experimental validation of the transition with 36 Cl standards Develop a chemical method of the transformation of Na 36 Cl into H 36 Cl Experimental measurements using the developed CRDS equipment on graphite samples

25 Task 5.2: CRDS for C-14 Investigation of the release behaviour of 14 C using CRDS Development of a sampling line dedicated to the collection of outgases Study of the release behaviour of C-14 from irradiated graphite waste Release behaviour of C-14 from another type of wastes such as organic waste Comparison with well-established techniques

26 Comparison with conventional techniques liquid scintillation counting used as the primary technique for 14 C and 36 Cl mass spectrometry for 36 Cl detection will also be explored by ENEA 36 Cl standards are available as Na 36 Cl, this work will require the study of the chemical transformation of Na 36 Cl into H 36 Cl

27 27 Outlook

28 New alternative for on-site on-line measurements + Compact, low cost + Real time measurement + Gas samples + No complex sample preparation + Small sample volume of a few ml + Only sensitive to one type of molecule

29 Radioactive emissions monitoring

30 Characterisation of waste outgassing

31 Waste monitoring

32 Monitoring of 14 C emissions from power plants stacks

33 Health and occupational safety during decomissioning

34 Characterisation of waste outgassing Waste monitoring Monitoring of 14 C emissions from power plants stacks Health and occupational safety during decomissioning

acrolein, acetaldehyde and acetone( cm -1 ); methanol (1306 cm -1 ); ethylene (949 cm -1 ); and isoprene (893 cm -1 ).

acrolein, acetaldehyde and acetone(1550 1800 cm -1 ); methanol (1306 cm -1 ); ethylene (949 cm -1 ); and isoprene (893 cm -1 ). 5 Figure 4a 6 Figure 4b Figure 4c 7 Figure 5 Questions in Student Handout