Quantities of I-131 and Cs-137 in accumulated water in the basements of reactor buildings in process of core cooling at Fukushima Daiichi nuclear power plants accident and its influence on late phase source terms

Water hammers, or fluid transients, compress flammable gasses to their autognition temperatures in piping systems to cause fires or explosions. While this statement may be true for many industrial systems, the focus of this research are reactor coolant water systems (RCW) in nuclear power plants, which generate flammable gasses during normal operations and during accident conditions, such as loss of coolant accidents (LOCA’s) or reactor meltdowns. When combustion occurs, the gas will either burn (deflagrate) or explode, depending on the system geometry and the quantity of the flammable gas and oxygen. If there is sufficient oxygen inside the pipe during the compression process, an explosion can ignite immediately. If there is insufficient oxygen to initiate combustion inside the pipe, the flammable gas can only ignite if released to air, an oxygen rich environment. This presentation considers the fundamentals of gas compression and causes of ignition in nuclear reactor systems. In addition to these ignition mechanisms, specific applications are briefly considered. Those applications include a hydrogen fire following the Three Mile Island meltdown, hydrogen explosions following Fukushima Daiichi explosions, and on-going fires and explosions in U.S nuclear power plants. Novel conclusions are presented here as follows. 1. A hydrogen fire was ignited by water hammer at Three Mile Island. 2. Hydrogen explosions were ignited by water hammer at Fukushima Daiichi. 3. Piping damages in U.S. commercial nuclear reactor systems have occurred since reactors were first built. These damages were not caused by water hammer alone, but were caused by water hammer compression of flammable hydrogen and resultant deflagration or detonation inside of the piping.

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Flood Hazard Reevaluation at Existing U.S. Nuclear Power Plants in Response to the Fukushima Daiichi Nuclear Power Plant Loss of Coolant Accident

World Environmental and Water Resources Congress 2014 ◽

10.1061/9780784413548.195 ◽

2014 ◽

Author(s):

Craig J. Talbot ◽

Kit Ng

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Nuclear Power ◽

Power Plants ◽

Nuclear Power Plants ◽

Flood Hazard ◽

Loss Of Coolant Accident ◽

Loss Of Coolant ◽

Fukushima Daiichi

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Emergency response to the nuclear accident at the Fukushima Daiichi Nuclear Power Plants using mobile rescue robots

Journal of Field Robotics ◽

10.1002/rob.21439 ◽

2012 ◽

Vol 30 (1) ◽

pp. 44-63 ◽

Cited By ~ 257

Author(s):

Keiji Nagatani ◽

Seiga Kiribayashi ◽

Yoshito Okada ◽

Kazuki Otake ◽

Kazuya Yoshida ◽

...

Keyword(s):

Emergency Response ◽

Nuclear Power ◽

Power Plants ◽

Nuclear Power Plants ◽

Nuclear Accident ◽

Fukushima Daiichi ◽

Rescue Robots

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Appearances of Fukushima Daiichi Nuclear Power Plant-Derived 137Cs in Coastal Waters around Japan: Results from Marine Monitoring off Nuclear Power Plants and Facilities, 1983–2016

Environmental Science & Technology ◽

10.1021/acs.est.7b03956 ◽

2018 ◽

Vol 52 (5) ◽

pp. 2629-2637 ◽

Cited By ~ 14

Author(s):

Hyoe Takata ◽

Masashi Kusakabe ◽

Naohiko Inatomi ◽

Takahito Ikenoue

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Coastal Waters ◽

Nuclear Power ◽

Power Plants ◽

Nuclear Power Plants ◽

Marine Monitoring ◽

Fukushima Daiichi

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Underground Siting of Nuclear Power Plants: Insights From Fukushima

Volume 2: Plant Systems, Structures, and Components; Safety and Security; Next Generation Systems; Heat Exchangers and Cooling Systems ◽

10.1115/icone20-power2012-54900 ◽

2012 ◽

Author(s):

Jay F. Kunze ◽

James M. Mahar ◽

Kellen M. Giraud ◽

C. W. Myers

Keyword(s):

Nuclear Power ◽

Power Plants ◽

Nuclear Power Plants ◽

Light Water Reactors ◽

Light Water ◽

Waste Storage ◽

Small Modular Reactor ◽

Fukushima Daiichi ◽

Water Reactors ◽

High Level

Siting of nuclear power plants in an underground nuclear park has been proposed by the authors in many previous publications, first focusing on how the present 1200 to 1600 MW-electric light water reactors could be sited underground, then including reprocessing and fuel manufacturing facilities, as well as high level permanent waste storage. Recently the focus has been on siting multiple small modular reactor systems. The recent incident at the Fukushima Daiichi site has prompted the authors to consider what the effects of a natural disaster such as the Japan earthquake and subsequent tsunami would have had if these reactors had been located underground. This paper addresses how the reactors might have remained operable — assuming the designs we previously proposed — and what lessons from the Fukushima incident can be learned for underground nuclear power plant designs.

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