Flash point, of fuels

Pensky-Martens dosed tester-apparatus used in determining the flash point of fuel oils and cutback asphalt, under conditions prescribed by test method ASTM D 93. The test sample is slowly heated in a closed cup, at a specified constant rate, with continual stirring. A small flame is introduced into the cup at specified... 

The Pensky-Martens closed tester (ASTM D-93, IP 34) and the tag closed tester (ASTM D-56) are normally used for determining the flash point of fuel oil and similar products. The Cleveland open cup method (ASTM D-92) is most commonly used, although the Tag open cup (ASTM D-3143) is applicable to cutback asphalt. As noted above, the flash point of asphalt is an indication of fire hazard and is frequently used to indicate whether asphalt has been contaminated with materials of lower flash point. 

Closed Cup (CC). A method used to determine the flash point of fuels, solvents, and cutback asphalts, utilizing a covered container in which the test sample is heated and periodically exposed to a small flame introduced through a shuttered opening. The lowest temperature at which the vapors above the sample briefly ignite is the flash point. 

The flash point of a petroleum liquid is the temperature to which it must be brought so that the vapor evolved burns spontaneously in the presence of a flame. For diesel fuel, the test is conducted according to a closed cup technique (NF T 60-103). The French specifications stipulate that the flash point should be between 55°C and 120°C. That constitutes a safety criterion during storage and distribution operations. Moreover, from an official viewpoint, petroleum products are classified in several groups according to their flash points which should never be exceeded. 

Commercial aviation utilizes low volatihty kerosene defined by a flash point minimum of 38 °C. The flammabiUty temperature has been invoked as a safety factor for handling fuels aboard aircraft carriers Navy JP-5 is a low volatihty kerosene of minimum flash point of 60 °C, similar to other Navy fuels. 

Flash Point. As fuel oil is heated, vapors are produced which at a certain temperature "flash" when ignited by an external ignition source. The flash point is the lowest temperature at which vapor, given off from a Hquid, is in sufficient quantity to enable ignition to take place. The flash point is in effect a measure of the volatiHty of the fuel. The measurement of flash point for pure Hquids is relatively straightforward. However, the measured value may depend slightly on the method used, especially for Hquid mixtures, since the composition of the vapor evolved can vary with the heating rate. Special... 

When the burner went out, the solenoid valve took a few see-onds to elose, and during this time some oil entered the furnaee. In addition, the line between the last valve and the furnaee may have drained into the furnaee. The flash point of the fuel oil was 65°C, too high for the oil to be deteeted by the eombustible gas deteetor. Even though the oil was vaporized by the hot furnaee, it would have eondensed in the sample tube of the gas deteetor or on the sintered metal that surrounds the deteetor head. 

The flash point of an oil is the temperature at which it gives off, under specified conditions, sufficient vapor to form a flammable mixture with air. This is very different from the temperature of spontaneous combustion. The test is an empirical one and the result depends upon the instm-ment used and the prescribed conditions. For example, the flash point may be closed or open , depending on whether the test apparatus has a lid or not. As far as lubricating oils are concerned, the test is of limited significance, although it can be indicative of contamination (for example, the dilution of crankcase oil by fuel). 

J. Use of fired heaters the presence of boilers or furnaces, heated by the combustion of fuels, increases the probability of ignition should a leak of flammable material occur from a process unit. The risk involved will depend on the siting of the fired equipment and the flash point of the process material. The factor to apply is determined with reference to Figure 6 in the Dow Guide. 

As for all petroleum products, considerations of safety in storage and transportation and, more particularly, contamination by more volatile products are required. This is usually accommodated by the Pensky-Martens flash point test (ASTM D93 IP 34). For the fuel oil, a minimum flash point of 55°C (131°F) or 66°C (150°F) is included in most specifications. 

Flash point is considered to be an important specification for all finished fuels and oils. The flammability and combustibility characteristics of a material are directly related to the flash point. Also, fuel transportation codes require flammable compounds to be appropriately labeled for safety reasons. 

There exists, in the literature on high internal phase emulsions, a small number of publications on possible applications of HIPEs, involving a diverse range of topics. The production of petroleum gels as safety fuels is one such example [124,125] this was mentioned in the section on non-aqueous HIPEs. The main advantage over conventional fuels is the prevention of spillage, which reduces the risk of fire in an accident. Also, studies on the flash-point of emulsified fuels [127] showed a considerable increase, compared to the liquid state, for commercial multicomponent fuels. In addition, there may be an enhancement of the efficiency of combustion of the fuel on emulsification, as it is known that a small amount of water in fuel can improve its performance [19]. 

Also according to Van Dolah ammonium nitrate-oil mixtures offer a certain dust explosion hazard and any electric equipment (switches controls, motors, lights) located in the plant should conform to the safety requirements or should be installed outside the plant. In order not to increase the dust explosion hazard no liquid hydrocarbon fuel with higher volatility than No. 2 Diesel fuel (minimum flash point of 145°F, ASTM closed-cup procedure) should be used as an admixture to ammonium nitrate. More volatile fuels, such as gasoline, kerosine or No. 1 Diesel fuel cannot be recommended according to Van Dolah, as they would seriously increase the hazard of a vapour explosion. 

In a diesel engine the contamination comes from the above and additional sources such as (a) soot as a normal by-product of diesel engine will increase the viscosity of the oil and become abrasive as its level increases in the oil (b) the fuel dilution will reduce the film strength of the oil to a point where accelerated wear occurs (c) the fuel dilution will reduce the flash-point of the oil (d) a diesel engine oil will also be exposed to the formation of acid from the sulfurized fuel max.5% a diesel engine will have a high TBN to assist it in combating the acid formation. 

Waste oil Used oil which contains in excess of 1000 ppm chlorine, 5 ppm arsenic, 2 ppm disposal cadmium, 10 ppm chromium, 100 ppm lead, or having a flash point of less than 40°C is considered to be hazardous waste and cannot be burned for energy recovery or used in any way to produce fuel. Waste oil containing more than 1000 ppm chlorine is considered to be contaminated with chlorinated solvents or PCB and is designated as hazardous waste. 

A flammable chemical substance is a solid, liquid, vapor, or gas that ignites easily and burns rapidly in air. Many of the flammable chemicals used in laboratories are flammable liquids and organic solvents. The vapors of these chemical substances form ignitable mixtures with air. Based on the flash points of these chemicals, classifications are made. The flash point of a chemical substance is defined as the lowest temperature at which a fuel-air mixture present above the surface of a liquid will ignite, if an ignition source is present. The common flammable chemical substances include, but are not restricted to, acetone, benzene, cyclohexane, ethanol, ethyl acetate, ethyl ether, gasoline, hexane, isopropyl alcohol, methanol, propanol, tetrahydro-furan and toluene, and xylene. 

The RON of gasoline obtained by thermal cracking or catalytic cracking is generally just about 80, and the flash point of diesel oil product is also very low. By isomerization and aromatization, catalytic reforming of cracked gas can greatly improve the quality of liquid fuel products. 

It is shown that after catalytic reformation, the quahty of liquid fuel produced is improved greatly. RON of gasoline reached more than 90 and the flash point of diesel oil also increased. 

Explain in your own words the concepts of heat of reaction exothermic and endothermic reactions heat of formation combustion heat of combustion standard heats of formation, combustion, and reaction heating value of a fuel adiabatic flame temperature ignition temperature ignition lag lower and upper flammability limits and flash point of a fuel a flame blue and yellow flames flashback and detonation. 

The flash point is also an important parameter when considering the possibility of using an oil as an alternative diesel fuel in ignition engines. The flash points of all vegetable oils are far above that of diesel fuel, reflecting the nonvolatile nature... 

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