Verification of the Efficacy of Passive Autocatalytic Recombiners in a Typical Pressurized Water Reactor under a Station Blackout Condition

The presence of a stable stratified gas cloud inside the containment near or at the flammability limit may lead to deflagration or even detonation which may challenge the containment and cause a radioactive material release into the environment. To mitigate this risk, a number of approaches have bee...

Full description

Saved in:
Bibliographic Details
Main Authors: Daegwang Hong, Donghyun Cho, Jinwoo Kim, Aya Diab, Cigdem Cildag
Format: Article
Language:English
Published: Wiley 2022-01-01
Series:Science and Technology of Nuclear Installations
Online Access:http://dx.doi.org/10.1155/2022/7129092
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832563892501348352
author Daegwang Hong
Donghyun Cho
Jinwoo Kim
Aya Diab
Cigdem Cildag
author_facet Daegwang Hong
Donghyun Cho
Jinwoo Kim
Aya Diab
Cigdem Cildag
author_sort Daegwang Hong
collection DOAJ
description The presence of a stable stratified gas cloud inside the containment near or at the flammability limit may lead to deflagration or even detonation which may challenge the containment and cause a radioactive material release into the environment. To mitigate this risk, a number of approaches have been proposed, for example, containment inerting or venting and use of passive autocatalytic recombiners or igniters. However, for these measures to be effective, a thorough analysis of the hydrogen dispersion and associated phenomena is indispensable during the design phase as well as the mitigation phase during a severe accident. In this work, a MAAP analysis is performed to assess the hydrogen risk in a typical pressurized water reactor (PWR) containment. An extended station blackout (SBO) was chosen as an initiating event given its high contribution to the core damage frequency. RCS depressurization and external injection are mitigation techniques implemented consecutively to extend the coping capability of the plant for the extended SBO scenario. A sensitivity study is performed to select the combination of timing and flow rate that generate the most severe case for the “in-vessel phase of hydrogen generation.” Subsequently, a number of passive autocatalytic recombiners (PARs) were implemented to mitigate the hydrogen risk during the first three days of the accident. The Shapiro diagram is used to assess the flammability condition of the containment atmosphere based on MAAP analysis. The results show that the gas mixture composition is acceptable in the majority of the containment compartments and only marginally acceptable in the cavity. Even under the conservative conditions of the accident, the simulation results confirmed the sufficiency of recombiners alone without igniters in the low hydrogen concentration zones, while for compartments close to the sources, additional mitigation may be needed.
format Article
id doaj-art-1e3a659475204651a27c36915cd4337f
institution Kabale University
issn 1687-6083
language English
publishDate 2022-01-01
publisher Wiley
record_format Article
series Science and Technology of Nuclear Installations
spelling doaj-art-1e3a659475204651a27c36915cd4337f2025-02-03T01:12:14ZengWileyScience and Technology of Nuclear Installations1687-60832022-01-01202210.1155/2022/7129092Verification of the Efficacy of Passive Autocatalytic Recombiners in a Typical Pressurized Water Reactor under a Station Blackout ConditionDaegwang Hong0Donghyun Cho1Jinwoo Kim2Aya Diab3Cigdem Cildag4KEPCO International Nuclear Graduate SchoolKEPCO International Nuclear Graduate SchoolKEPCO International Nuclear Graduate SchoolKEPCO International Nuclear Graduate SchoolKEPCO International Nuclear Graduate SchoolThe presence of a stable stratified gas cloud inside the containment near or at the flammability limit may lead to deflagration or even detonation which may challenge the containment and cause a radioactive material release into the environment. To mitigate this risk, a number of approaches have been proposed, for example, containment inerting or venting and use of passive autocatalytic recombiners or igniters. However, for these measures to be effective, a thorough analysis of the hydrogen dispersion and associated phenomena is indispensable during the design phase as well as the mitigation phase during a severe accident. In this work, a MAAP analysis is performed to assess the hydrogen risk in a typical pressurized water reactor (PWR) containment. An extended station blackout (SBO) was chosen as an initiating event given its high contribution to the core damage frequency. RCS depressurization and external injection are mitigation techniques implemented consecutively to extend the coping capability of the plant for the extended SBO scenario. A sensitivity study is performed to select the combination of timing and flow rate that generate the most severe case for the “in-vessel phase of hydrogen generation.” Subsequently, a number of passive autocatalytic recombiners (PARs) were implemented to mitigate the hydrogen risk during the first three days of the accident. The Shapiro diagram is used to assess the flammability condition of the containment atmosphere based on MAAP analysis. The results show that the gas mixture composition is acceptable in the majority of the containment compartments and only marginally acceptable in the cavity. Even under the conservative conditions of the accident, the simulation results confirmed the sufficiency of recombiners alone without igniters in the low hydrogen concentration zones, while for compartments close to the sources, additional mitigation may be needed.http://dx.doi.org/10.1155/2022/7129092
spellingShingle Daegwang Hong
Donghyun Cho
Jinwoo Kim
Aya Diab
Cigdem Cildag
Verification of the Efficacy of Passive Autocatalytic Recombiners in a Typical Pressurized Water Reactor under a Station Blackout Condition
Science and Technology of Nuclear Installations
title Verification of the Efficacy of Passive Autocatalytic Recombiners in a Typical Pressurized Water Reactor under a Station Blackout Condition
title_full Verification of the Efficacy of Passive Autocatalytic Recombiners in a Typical Pressurized Water Reactor under a Station Blackout Condition
title_fullStr Verification of the Efficacy of Passive Autocatalytic Recombiners in a Typical Pressurized Water Reactor under a Station Blackout Condition
title_full_unstemmed Verification of the Efficacy of Passive Autocatalytic Recombiners in a Typical Pressurized Water Reactor under a Station Blackout Condition
title_short Verification of the Efficacy of Passive Autocatalytic Recombiners in a Typical Pressurized Water Reactor under a Station Blackout Condition
title_sort verification of the efficacy of passive autocatalytic recombiners in a typical pressurized water reactor under a station blackout condition
url http://dx.doi.org/10.1155/2022/7129092
work_keys_str_mv AT daegwanghong verificationoftheefficacyofpassiveautocatalyticrecombinersinatypicalpressurizedwaterreactorunderastationblackoutcondition
AT donghyuncho verificationoftheefficacyofpassiveautocatalyticrecombinersinatypicalpressurizedwaterreactorunderastationblackoutcondition
AT jinwookim verificationoftheefficacyofpassiveautocatalyticrecombinersinatypicalpressurizedwaterreactorunderastationblackoutcondition
AT ayadiab verificationoftheefficacyofpassiveautocatalyticrecombinersinatypicalpressurizedwaterreactorunderastationblackoutcondition
AT cigdemcildag verificationoftheefficacyofpassiveautocatalyticrecombinersinatypicalpressurizedwaterreactorunderastationblackoutcondition