You need JavaScript to view this

Interactions of fission product vapours with aerosols

Abstract

Reactions between structural and reactor materials aerosols and fission product vapours released during a severe accident in a light water reactor (LWR) will influence the magnitude of the radiological source term ultimately released to the environment. The interaction of cadmium aerosol with iodine vapour at different temperatures has been examined in a programme of experiments designed to characterise the kinetics of the system. Laser induced fluorescence (LIF) is a technique that is particularly amenable to the study of systems involving elemental iodine because of the high intensity of the fluorescence lines. Therefore this technique was used in the experiments to measure the decrease in the concentration of iodine vapour as the reaction with cadmium proceeded. Experiments were conducted over the range of temperatures (20-350{sup o}C), using calibrated iodine vapour and cadmium aerosol generators that gave well-quantified sources. The LIF results provided information on the kinetics of the process, whilst examination of filter samples gave data on the composition and morphology of the aerosol particles that were formed. The results showed that the reaction of cadmium with iodine was relatively fast, giving reaction half-lives of approximately 0.3 s. This suggests that the assumption used by primary circuit codes such as VICTORIA  More>>
Authors:
Benson, C G; Newland, M S [1] 
  1. AEA Technology, Winfrith (United Kingdom)
Publication Date:
Dec 01, 1996
Product Type:
Technical Report
Report Number:
PSI-97-02; CONF-9606320-; NEA/CSNI/R(96)-6.
Reference Number:
SCA: 400201; 400700; 220900; PA: AIX-28:035728; EDB-97:080849; SN: 97001795073
Resource Relation:
Conference: 4. CSNI workshop on the chemistry of iodine in reactor safety, Wuerenlingen (Switzerland), 10-12 Jun 1996; Other Information: PBD: Dec 1996; Related Information: Is Part Of Proceedings of the 4. CSNI workshop on the chemistry of iodine in reactor safety; Guentay, S. [ed.] [Paul Scherrer Inst. (PSI), Villigen (Switzerland)]; PB: 716 p.
Subject:
40 CHEMISTRY; 22 NUCLEAR REACTOR TECHNOLOGY; CADMIUM; AEROSOLS; FISSION PRODUCTS; VAPORS; WATER COOLED REACTORS; REACTOR ACCIDENTS; CHEMICAL REACTION KINETICS; COMPUTERIZED SIMULATION; EXPERIMENTAL DATA; FLUORESCENCE; IODINE; LASER RADIATION; V CODES; SOURCE TERMS
OSTI ID:
481451
Research Organizations:
Paul Scherrer Inst. (PSI), Villigen (Switzerland)
Country of Origin:
Switzerland
Language:
English
Other Identifying Numbers:
Other: ON: DE97624048; TRN: CH9700208035728
Availability:
INIS; OSTI as DE97624048
Submitting Site:
CHN
Size:
pp. 233-281
Announcement Date:

Citation Formats

Benson, C G, and Newland, M S. Interactions of fission product vapours with aerosols. Switzerland: N. p., 1996. Web.
Benson, C G, & Newland, M S. Interactions of fission product vapours with aerosols. Switzerland.
Benson, C G, and Newland, M S. 1996. "Interactions of fission product vapours with aerosols." Switzerland.
@misc{etde_481451,
title = {Interactions of fission product vapours with aerosols}
author = {Benson, C G, and Newland, M S}
abstractNote = {Reactions between structural and reactor materials aerosols and fission product vapours released during a severe accident in a light water reactor (LWR) will influence the magnitude of the radiological source term ultimately released to the environment. The interaction of cadmium aerosol with iodine vapour at different temperatures has been examined in a programme of experiments designed to characterise the kinetics of the system. Laser induced fluorescence (LIF) is a technique that is particularly amenable to the study of systems involving elemental iodine because of the high intensity of the fluorescence lines. Therefore this technique was used in the experiments to measure the decrease in the concentration of iodine vapour as the reaction with cadmium proceeded. Experiments were conducted over the range of temperatures (20-350{sup o}C), using calibrated iodine vapour and cadmium aerosol generators that gave well-quantified sources. The LIF results provided information on the kinetics of the process, whilst examination of filter samples gave data on the composition and morphology of the aerosol particles that were formed. The results showed that the reaction of cadmium with iodine was relatively fast, giving reaction half-lives of approximately 0.3 s. This suggests that the assumption used by primary circuit codes such as VICTORIA that reaction rates are mass-transfer limited, is justified for the cadmium-iodine reaction. The reaction was first order with respect to both cadmium and iodine, and was assigned as pseudo second order overall. However, there appeared to be a dependence of aerosol surface area on the overall rate constant, making the precise order of the reaction difficult to assign. The relatively high volatility of the cadmium iodide formed in the reaction played an important role in determining the composition of the particles. (author) 23 figs., 7 tabs., 22 refs.}
place = {Switzerland}
year = {1996}
month = {Dec}
}