Flammable gas project: Criteria for flammable gas watch list tanks

Directive 2013/39/EU amending Directives 2000/60/EC and 2008/105/EC as regards priority substances in the field of water policy was adopted on 12 August 2013. It revises crucial rules on determining the chemical quality of surface water in Europe (e.g. identification of new harmful substances, updating of environmental quality standards, introduction of a new “watch list” mechanism) and establishes new standards for the protection of water in Europe. This paper explores the legal and factual background to the new legislation on protecting water quality in Europe and takes a critical look at its most important provisions.

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Nuclear Power Plant Fires and Explosions: Part IV — Water Hammer Explosion Mechanisms

Volume 4: Fluid-Structure Interaction ◽

10.1115/pvp2017-66279 ◽

2017 ◽

Cited By ~ 1

Author(s):

Robert A. Leishear

Keyword(s):

Nuclear Power ◽

Power Plants ◽

Nuclear Power Plants ◽

Nuclear Reactor ◽

Water Hammer ◽

Compression Process ◽

Flammable Gas ◽

Piping Systems ◽

Fukushima Daiichi ◽

Accident Conditions

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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STUDY OF GAS FUEL LEAKAGE AND EXPLOSION IN THE ENGINE ROOM OF A SMALL LNG-FUELED SHIP

The International Journal of Maritime Engineering ◽

10.5750/ijme.v161ia3.1096 ◽

2021 ◽

Vol 161 (A3) ◽

Author(s):

Q G Zheng ◽

W Q Wu ◽

M Song

Keyword(s):

Injury Risk ◽

Engine Fuel ◽

Limited Region ◽

Gas Dispersion ◽

Engine Room ◽

Flammable Gas ◽

Gas Fuel ◽

Fuel Leakage ◽

Gas Cloud ◽

The Given

The engine fuel piping in LNG-fuelled ships’ engine room presents potential gas explosion risks due to possible gas fuel leakage and dispersion. A 3D CFD model with chemical reaction was described, validated and then used to simulate the possible gas dispersion and the consequent explosions in an engine room with regulations commanded ventilations. The results show that, with the given minor leaking of a fuel pipe, no more than 1kg of methane would accumulate in the engine room. The flammable gas clouds only exit in limited region and could lead to explosions with an overpressure about 12 mbar, presenting no injury risk to personnel. With the given major leaking, large region in the engine room would be filled with flammable gas cloud within tens of seconds. The gas cloud might lead to an explosion pressure of about 1 bar or higher, which might result in serious casualties in the engine room.

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