Ignition point fuel oils

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... 

Kerosene or sometimes referred to as Fuel Oil 1 is a refined petroleum distillate. Kerosenes usually have flash points within the range of 37.8 °C to 54.4 °C (100 °F to 130 °F). Therefore unless heated, kerosene will usually not produce ignitable mixtures over its surface. In atmospheric burning smoke production normally occurs. It is commonly used as a fuel and a solvent. In some applications it is treated with sulfuric acid to reduce the content of aromatics, which bum with a smoky flame. 

Cleveland Open Cup (COC)-test (ASTM D 92) for determining the flash point and fire point of all petroleum products except fuel oil and products with flash points below 79oC (175oF). The oil sample is heated in a precisely specified brass cup containing a thermometer, specified intervals a small flame is passed across the cup. The lowest temperature at which the vapors above the cup briefly ignite is the flash point the temperature at which the vapors sustain combustion for at least five seconds is the fire point. See Tag open cup. 

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... 

The above parameters are relevant when pumping oils at low temperatures or for their use as alternative diesel fuel in ignition engines. The cloud points and pour points of the vegetable oils are higher than for diesel fuel. 

The flash point is a measure of the temperature to which fuel oil must be heated to produce an ignitable vapor-air mixture above the liquid fuel when exposed to an open flame. Following from this, the fire point of a fuel is the temperature at which an oil in an open container gives off vapor at a sufficient rate to continue to burn after a flame is applied. 

Flash point the lowest temperature at which vapours above a liquid will ignite when exposed to an ignition source. For example, the flash point of a No.l fuel oil is 54°C (open cup) and 59°C (closed cup). Materials transported above their flash points present a significant risk of fire if they come into contact with electrical equipment, electrostatic sparks, automotive ignition systems, open flames, and other ignition systems. 

Flammable liquids may not continue to bum after they have been ignited at their flash point. The temperature at which flammable liquids evolve vapours quickly enough to support sustained and continuous combustion is the fire point. A typical sample of No. 1 fuel oil may have a closed-cup flash point of 54°C, an open-cup flash point of 59°C, and a fire point of 63°C. See Terminology, Combustion, p.233 Terminology, Volatile, p.252. 

Liquids with high flash points (combustible liquids) are less likely to ignite under typical atmospheric conditions, although when the ambient temperature is elevated, those liquids are prone to act similarly to flammable liquids. Examples include diesel fuel (fuel oil 2) with a flash point of 120°F dispersed on asphalt pavement during hot summer days. External heating can raise the fuel above its flash point thus sufficient vapors will be present to sustain a flame should the minimum ignition energy be introduced. 

The fuels consumed in the fire were treated wood, penta, and creosote (coal tars). Both are considered combustible liquids, with flash points above 160° F (CC). Vapor conditions within the headspaces of tanks can, however, reach explosive conditions, and the introduction of an ignition source resulted in spontaneous combustion. Under ideal conditions, creosote burns similar to crude oil, and in standard lab burn tests, has an average burn rate of 4 mm/min. There is no data on the burn rate of penta however, its vapors would have likely burned at much slower rates and a series of complex chemical transformations would have occurred. 

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