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Inerting (gas)
In fire and explosion prevention engineering, inerting refers to the introduction of an inert gas, inert (non-combustible) gas into a closed system (e.g. a container or a process vessel) to make a flammable atmosphere oxygen deficient and non-ignitable.NFPA 69. Standard on Explosion Prevention Systems. National Fire Protection Association.NFPA 77. Recommended Practice on Static Electricity. National Fire Protection Association. Inerting relies on the principle that a combustible (or flammable) gas is able to undergo combustion (explode) only if mixed with air in the right proportions. The flammability limits of the gas define those proportions, i.e. the ignitable range. In combustion engineering terms, the admission of inert gas can be said to dilute the oxygen below the limiting oxygen concentration. Inerting differs from Purging (gas), purging. Purging, by definition, ensures that an ignitable mixture ''never forms''. Inerting makes an ignitable mixture safe by introduction o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inert Gas
An inert gas is a gas that does not readily undergo chemical reactions with other chemical substances and therefore does not readily form chemical compounds. Though inert gases have a variety of applications, they are generally used to prevent unwanted chemical reactions with the oxygen (oxidation) and moisture (hydrolysis) in the air from degrading a sample. Generally, all noble gases except oganesson (helium, neon, argon, krypton, xenon, and radon), nitrogen, and carbon dioxide are considered inert gases. The term ''inert gas'' is context-dependent because several of the inert gases, including nitrogen and carbon dioxide, can be made to react under certain conditions. Purified argon gas is the most commonly used inert gas due to its high natural abundance (78.3% N2, 1% Ar in air) and low relative cost. Unlike noble gases, an inert gas is not necessarily elemental and is often a compound gas. Like the noble gases, the tendency for non-reactivity is due to the valence, the ou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flammability Limits
Flammability limits or explosive limits are the ranges of fuel concentrations in relation to oxygen from the air. Combustion can range in violence from deflagration through detonation. Limits vary with temperature and pressure, but are normally expressed in terms of volume percentage at 25 °C and atmospheric pressure. These limits are relevant both in producing and optimising explosion or combustion, as in an engine, or to preventing it, as in uncontrolled explosions of build-ups of combustible gas or dust. Attaining the best combustible or explosive mixture of a fuel and air (the stoichiometric proportion) is important in internal combustion engines such as gasoline or diesel engines. The standard reference work is still that elaborated by Michael George Zabetakis, a fire safety engineering specialist, using an apparatus developed by the United States Bureau of Mines. Violence of combustion Combustion can vary in degree of violence. A deflagration is a propagation of a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limiting Oxygen Concentration
The limiting oxygen concentration (LOC), also known as the minimum oxygen concentration (MOC), is defined as the limiting concentration of oxygen below which combustion is not possible, independent of the concentration of fuel. It is expressed in units of volume percent of oxygen. The LOC varies with pressure and temperature. It is also dependent on the type of inert (non-flammable) gas. Limiting oxygen concentration for solid materials The effect of increasing the concentration of inert gas can be understood by viewing the inert as thermal ballast that quenches the flame temperature to a level below which the flame cannot exist. Carbon dioxide is therefore more effective than nitrogen due to its higher molar heat capacity.Drysdale:92 The concept has important practical use in fire safety engineering. For instance, to safely fill a new container or a pressure vessel with flammable gases, the atmosphere of normal air (containing 20.9 volume percent of oxygen) in the vesse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Purging (gas)
In fire and explosion prevention engineering, purging refers to the introduction of an inert (i.e. non-combustible) purge gas into a closed system (e.g. a container or a process vessel) to prevent the formation of an ignitable atmosphere. Purging relies on the principle that a combustible (or flammable) gas is able to undergo combustion (explode) only if mixed with air in the right proportions. The flammability limits of the gas define those proportions, i.e. the ignitable range. Purge into service Assume a closed system (e.g. a container or process vessel), initially containing air, which shall be prepared for safe introduction of a flammable gas, for instance as part of a start-up procedure. The system can be flushed with an inert gas to reduce the concentration of oxygen so that when the flammable gas is admitted, an ignitable mixture cannot form. In NFPA 56,NFPA 56. Standard for Fire and Explosion Prevention During Cleaning and Purging of Flammable Gas Piping Systems. Nat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1954 Bitburg Explosion (jet Fuel Storage Tank)
The devastating Bitburg tank explosion took place on 23 September 1954 at the then NATO air base near the city Bitburg, in the municipality of Niederstedem, Germany. The explosion took place in an underground storage tank containing JP-4, a military jet fuel blend. The toll was 34 dead, 2 injured, 3 missing. The explosion was caused by the deliberate activation of a novel carbon dioxide fire extinguishment system during an acceptance test as part of final commissioning. The JP-4 blend has since largely been abandoned due to safety concerns because of its low flash point. The accident In 1954 at the US Air Force fuel depot near Bitburg, various acceptance tests were being made on a newly constructed underground fuel storage tank. The tank was fitted with a novel carbon dioxide fire extinguishing system, the first of its kind in Germany. The US Army was not responsible for design, construction and operation of storage facilities at the time, but the fuel involved was the property o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crude Oil
Petroleum, also known as crude oil or simply oil, is a naturally occurring, yellowish-black liquid chemical mixture found in geological formations, consisting mainly of hydrocarbons. The term ''petroleum'' refers both to naturally occurring unprocessed crude oil, as well as to petroleum products that consist of refined crude oil. Petroleum is a fossil fuel formed over millions of years from anaerobic decay of organic materials from buried prehistoric organisms, particularly planktons and algae, and 70% of the world's oil deposits were formed during the Mesozoic. Conventional reserves of petroleum are primarily recovered by drilling, which is done after a study of the relevant structural geology, analysis of the sedimentary basin, and characterization of the petroleum reservoir. There are also unconventional reserves such as oil sands and oil shale which are recovered by other means such as fracking. Once extracted, oil is refined and separated, most easily by disti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naphtha
Naphtha (, recorded as less common or nonstandard in all dictionaries: ) is a flammable liquid hydrocarbon mixture. Generally, it is a fraction of crude oil, but it can also be produced from natural-gas condensates, petroleum distillates, and the fractional distillation of coal tar and peat. In some industries and regions, the name ''naphtha'' refers to crude oil or refined petroleum products such as kerosene or diesel fuel. Naphtha is also known as Shellite in Australia. Etymology The word ''naphtha'' comes from Latin through Ancient Greek (), derived from Middle Persian ''naft'' ("wet", "naphtha"), the latter meaning of which was an assimilation from the Akkadian 𒉌𒆳𒊏 (see Semitic relatives such as Arabic petroleum" Syriac ''naftā'', and Hebrew , meaning petroleum). Antiquity The book of II Maccabees (2nd cent. BC) tells how a "thick water" was put on a sacrifice at the time of Nehemiah and when the sun shone it caught fire. It adds that "those aro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gasoline
Gasoline ( North American English) or petrol ( Commonwealth English) is a petrochemical product characterized as a transparent, yellowish, and flammable liquid normally used as a fuel for spark-ignited internal combustion engines. When formulated as a fuel for engines, gasoline is chemically composed of organic compounds derived from the fractional distillation of petroleum and later chemically enhanced with gasoline additives. It is a high-volume profitable product produced in crude oil refineries. The ability of a particular gasoline blend to resist premature ignition (which causes knocking and reduces efficiency in reciprocating engines) is measured by its octane rating. Tetraethyl lead was once widely used to increase the octane rating but is not used in modern automotive gasoline due to the health hazard. Aviation, off-road motor vehicles, and racing car engines still use leaded gasolines. Other substances are frequently added to gasoline to improve chemical st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inert Gas Generator
Inert gas generator (IGG) refers to machinery on board marine product tankers. Inert gas generators consist distinctively of a gas producer and a scrubbing system. Process Diesel is burned using atmospheric air in a combustion chamber and the exhaust gas collected, the resulting exhaust gas contains less than 5% oxygen, thereby creating "inert gas", which mainly consist of nitrogen and partly carbon dioxide Carbon dioxide is a chemical compound with the chemical formula . It is made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at norma .... The hot, dirty gas is then passed through a scrubbing tower which cleans and cools it using seawater. This gas is then delivered to cargo tanks to prevent explosion of flammable cargo. This generator is sometimes confused with ''flue gas systems'', which draw inert gas from the boiler systems of the ship. Flue gas systems d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Purging (gas)
In fire and explosion prevention engineering, purging refers to the introduction of an inert (i.e. non-combustible) purge gas into a closed system (e.g. a container or a process vessel) to prevent the formation of an ignitable atmosphere. Purging relies on the principle that a combustible (or flammable) gas is able to undergo combustion (explode) only if mixed with air in the right proportions. The flammability limits of the gas define those proportions, i.e. the ignitable range. Purge into service Assume a closed system (e.g. a container or process vessel), initially containing air, which shall be prepared for safe introduction of a flammable gas, for instance as part of a start-up procedure. The system can be flushed with an inert gas to reduce the concentration of oxygen so that when the flammable gas is admitted, an ignitable mixture cannot form. In NFPA 56,NFPA 56. Standard for Fire and Explosion Prevention During Cleaning and Purging of Flammable Gas Piping Systems. Nat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ATEX
The ATEX directives are two of the EU directives describing the minimum safety requirements for workplaces and equipment used in explosive atmospheres. The name is an initialization of the term ''ATmosphères EXplosives'' ( French for "explosive atmospheres"). Directives Organizations in the EU must follow Directives to protect employees from explosion risk in areas with an explosive atmosphere. There are two ATEX Directives (one for the manufacturer and one for the user of the equipment): * The ATEX 114 "equipment" Directive 2014/34/EU - Equipment and protective systems intended for use in potentially explosive atmospheres * The ATEX 153 "workplace" Directive 1999/92/EC - Minimum requirements for improving the safety and health protection of workers potentially at risk from explosive atmospheres. Note: The ATEX 95 "equipment" Directive 94/9/EC, was withdrawn on 20 April 2016 when it was replaced by ATEX 114 Directive 2014/34/EU. ATEX Directive 2014/34/EU is mandatory ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flammability Limits
Flammability limits or explosive limits are the ranges of fuel concentrations in relation to oxygen from the air. Combustion can range in violence from deflagration through detonation. Limits vary with temperature and pressure, but are normally expressed in terms of volume percentage at 25 °C and atmospheric pressure. These limits are relevant both in producing and optimising explosion or combustion, as in an engine, or to preventing it, as in uncontrolled explosions of build-ups of combustible gas or dust. Attaining the best combustible or explosive mixture of a fuel and air (the stoichiometric proportion) is important in internal combustion engines such as gasoline or diesel engines. The standard reference work is still that elaborated by Michael George Zabetakis, a fire safety engineering specialist, using an apparatus developed by the United States Bureau of Mines. Violence of combustion Combustion can vary in degree of violence. A deflagration is a propagation of a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
