Effect of selected binary and mixed solutions on steam condensation and aerosol behavior in containment

Jorma Jokiniemi

Research output: Contribution to journalArticleScientificpeer-review

16 Citations (Scopus)

Abstract

In the course of severe light water reactor (LWR) core melt accidents, the formation and presence of water soluble compounds will affect the behavior of fission products in the primary system and in the containment.
A liquid aerosol mixed with an insoluble component has an affinity to stick on surfaces. A relocation of the deposited aerosol may occur depending on the mole fraction of the solid component and the viscosity of the liquid component in the deposited material. In the very humid conditions expected in the containment, steam will condense on the hygroscopic particles, thereby increasing the size of the particles and settling rate.
As a first step in modeling the effects of hygroscopicity, the water activity of a CsOH solution was implemented in the condensation model. The model predicts a significant contribution of CsOH hygroscopicity on the suspended mass concentration, which is in accordance with the observations from the latest large-scale containment aerosol experiments. Results of this simplified CsOH hygroscopicity model were compared with aerosol particles consisting of mixed solutions (e.g., CsOH—Cs2CO3—CsI—H2O) expected in particles released during severe accidents.
Water activities of binary and mixed solutions were first calculated using semiempirical methods and these results were compared with the available experimental data. Secondly, different heat and mass transfer models were compared to find a suitable method for the growth rate calculations of hygroscopic aerosol particles.
We can conclude that sedimentation of hygroscopic aerosols is an effective removal mechanism for airborne fission products at a high relative humidity in the LWR containment during severe core melt accidents.

Original languageEnglish
Pages (from-to)891-902
JournalAerosol Science and Technology
Volume12
Issue number4
DOIs
Publication statusPublished - 1990
MoE publication typeA1 Journal article-refereed

Fingerprint

Steam
containment
Aerosols
condensation
Condensation
aerosol
hygroscopicity
accident
Accidents
Light water reactors
Fission products
Particles (particulate matter)
Water
water
melt
liquid
Relocation
Reactor cores
Liquids
relocation

Cite this

@article{159da4a538294991a995d62d8b7ae9c2,
title = "Effect of selected binary and mixed solutions on steam condensation and aerosol behavior in containment",
abstract = "In the course of severe light water reactor (LWR) core melt accidents, the formation and presence of water soluble compounds will affect the behavior of fission products in the primary system and in the containment. A liquid aerosol mixed with an insoluble component has an affinity to stick on surfaces. A relocation of the deposited aerosol may occur depending on the mole fraction of the solid component and the viscosity of the liquid component in the deposited material. In the very humid conditions expected in the containment, steam will condense on the hygroscopic particles, thereby increasing the size of the particles and settling rate. As a first step in modeling the effects of hygroscopicity, the water activity of a CsOH solution was implemented in the condensation model. The model predicts a significant contribution of CsOH hygroscopicity on the suspended mass concentration, which is in accordance with the observations from the latest large-scale containment aerosol experiments. Results of this simplified CsOH hygroscopicity model were compared with aerosol particles consisting of mixed solutions (e.g., CsOH—Cs2CO3—CsI—H2O) expected in particles released during severe accidents. Water activities of binary and mixed solutions were first calculated using semiempirical methods and these results were compared with the available experimental data. Secondly, different heat and mass transfer models were compared to find a suitable method for the growth rate calculations of hygroscopic aerosol particles. We can conclude that sedimentation of hygroscopic aerosols is an effective removal mechanism for airborne fission products at a high relative humidity in the LWR containment during severe core melt accidents.",
author = "Jorma Jokiniemi",
year = "1990",
doi = "10.1080/02786829008959401",
language = "English",
volume = "12",
pages = "891--902",
journal = "Aerosol Science and Technology",
issn = "0278-6826",
publisher = "Taylor & Francis",
number = "4",

}

Effect of selected binary and mixed solutions on steam condensation and aerosol behavior in containment. / Jokiniemi, Jorma.

In: Aerosol Science and Technology, Vol. 12, No. 4, 1990, p. 891-902.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Effect of selected binary and mixed solutions on steam condensation and aerosol behavior in containment

AU - Jokiniemi, Jorma

PY - 1990

Y1 - 1990

N2 - In the course of severe light water reactor (LWR) core melt accidents, the formation and presence of water soluble compounds will affect the behavior of fission products in the primary system and in the containment. A liquid aerosol mixed with an insoluble component has an affinity to stick on surfaces. A relocation of the deposited aerosol may occur depending on the mole fraction of the solid component and the viscosity of the liquid component in the deposited material. In the very humid conditions expected in the containment, steam will condense on the hygroscopic particles, thereby increasing the size of the particles and settling rate. As a first step in modeling the effects of hygroscopicity, the water activity of a CsOH solution was implemented in the condensation model. The model predicts a significant contribution of CsOH hygroscopicity on the suspended mass concentration, which is in accordance with the observations from the latest large-scale containment aerosol experiments. Results of this simplified CsOH hygroscopicity model were compared with aerosol particles consisting of mixed solutions (e.g., CsOH—Cs2CO3—CsI—H2O) expected in particles released during severe accidents. Water activities of binary and mixed solutions were first calculated using semiempirical methods and these results were compared with the available experimental data. Secondly, different heat and mass transfer models were compared to find a suitable method for the growth rate calculations of hygroscopic aerosol particles. We can conclude that sedimentation of hygroscopic aerosols is an effective removal mechanism for airborne fission products at a high relative humidity in the LWR containment during severe core melt accidents.

AB - In the course of severe light water reactor (LWR) core melt accidents, the formation and presence of water soluble compounds will affect the behavior of fission products in the primary system and in the containment. A liquid aerosol mixed with an insoluble component has an affinity to stick on surfaces. A relocation of the deposited aerosol may occur depending on the mole fraction of the solid component and the viscosity of the liquid component in the deposited material. In the very humid conditions expected in the containment, steam will condense on the hygroscopic particles, thereby increasing the size of the particles and settling rate. As a first step in modeling the effects of hygroscopicity, the water activity of a CsOH solution was implemented in the condensation model. The model predicts a significant contribution of CsOH hygroscopicity on the suspended mass concentration, which is in accordance with the observations from the latest large-scale containment aerosol experiments. Results of this simplified CsOH hygroscopicity model were compared with aerosol particles consisting of mixed solutions (e.g., CsOH—Cs2CO3—CsI—H2O) expected in particles released during severe accidents. Water activities of binary and mixed solutions were first calculated using semiempirical methods and these results were compared with the available experimental data. Secondly, different heat and mass transfer models were compared to find a suitable method for the growth rate calculations of hygroscopic aerosol particles. We can conclude that sedimentation of hygroscopic aerosols is an effective removal mechanism for airborne fission products at a high relative humidity in the LWR containment during severe core melt accidents.

U2 - 10.1080/02786829008959401

DO - 10.1080/02786829008959401

M3 - Article

VL - 12

SP - 891

EP - 902

JO - Aerosol Science and Technology

JF - Aerosol Science and Technology

SN - 0278-6826

IS - 4

ER -