Fuels flash point

Dependent on fuel flash point and LEL values which are dependent on tank characteristics (which are not modelled). 

Diesel Fuel Safety as Characterized by Its 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. 

It should be noted finally that adding gasoline to diesel fuel which was sometimes recommended in the past to improve cold behavior conflicts with the flash point specifications and presents a serious safety problem owing to the presence of a flammable mixture in the fuel tank airspace. Adding a kerosene that begins to boil at 150°C does not have the Scune disadvantage from this point of view. 

First, your Nitromethane may require purification, especially if it w/ as for "fuel" use. In this case, it needs to be vacuum distilled at a vacuum of better than 100mm Hg. At that pressure, it will come off at 47C. Distillation at atmospheric pressure is possible, but I do not recommend it due to the highly flammable nature of the compound and because it s flash point is 42C. It s your choice. 

Furfuryl alcohol is comparable to kerosene or No. 1 fuel oil in flammabiUty, the Tag Closed Cup flash point is 170°F. In the presence of concentrated mineral acids or strong organic acids, furfuryl alcohol reacts with explosive violence. Therefore, precautions should be taken to avoid contact of such materials with the alcohol. Caution is also recommended to avoid over-catalysis in the manufacture of furfuryl alcohol resins. 

Liquid fuels for ground-based gas turbines are best defined today by ASTM Specification D2880. Table 4 Hsts the detailed requirements for five grades which cover the volatility range from naphtha to residual fuel. The grades differ primarily in basic properties related to volatility eg, distillation, flash point, and density of No. 1 GT and No. 2 GT fuels correspond to similar properties of kerosene and diesel fuel respectively. These properties are not limited for No. 0 GT fuel, which allows naphthas and wide-cut distillates. For heavier fuels. No. 3 GT and No. 4 GT, the properties that must be limited are viscosity and trace metals. 

Specifications for gas turbine fuels prescribe test limits that must be met by the refiner who manufactures fuel however, it is customary for fuel users to define quality control limits for fuel at the point of delivery or of custody transfer. These limits must be met by third parties who distribute and handle fuels on or near the airport. Tests on receipt at airport depots include appearance, distfllation, flash point (or vapor pressure), density, freezing point, smoke point, corrosion, existing gum, water reaction, and water separation. Tests on delivery to the aircraft include appearance, particulates, membrane color, free water, and electrical conductivity. 

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. 

The dependence of vapor pressure on temperature for the fuels most commonly used in gas turbines appears in Figure 8 (14). The points on the abscissa reflect the flash point temperatures used to define the volatihty of higher molecular weight fuels. When vapor pressure itself is limited, as with JP-4 or Jet B, a test temperature of 38°C is specified. 

Ground turbine fuels are not subject to the constraints of an aircraft operating at reduced pressures of altitude. The temperature of fuel in ground tanks varies over a limited range, eg, 10—30°C, and the vapor pressure is defined by a safety-handling factor such as flash point temperature. Volatile fuels such as naphtha (No. 0-GT) are normally stored in a ground tank equipped with a vapor recovery system to minimise losses and meet local air quaUty codes on hydrocarbons. 

Factors in Using Kerosene Jet Fuel of Reduced Flash Point, AFTM. STP 688, American Society for Testing Materials, Philadelphia, Pa., 1979. 

Fig. 1. Effect of temperature on limits of flammabiUty of a pure Hquid fuel ia air, where = lean (or lower) flash point = rich (or upper) flash point ...

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... 

Crude oils with flash points below 311 K (100°F) have been used in place of No. 6 fuel oil. Different pumps may be required because of low fuel viscosity. 

Important liquid fuel properties for a gas turbine are shown in Table 12-5. The flash point is the temperature at which vapors begin combustion. The flash point is the maximum temperature at which a fuel can be handled safely. 

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. 

Flash point The lowest temperature at which a heated liquid fuel will ignite. 

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. 

Before relighting a hot furnaee that burns fuel oil with a flash point above ambient temperature, sweep it out for a period of time, long enough to make sure that any unburnt oil has evaporated. If this eauses too mueh delay, then pilot burners supplied by an alternative supply should be kept alight at all times. 

This term is used to describe oils that have a flash point above ambient temperature. They will therefore not burn or explode at ambient temperature but will do so when hot. Unfortunately many people do not realize this and treat heavy oils with a disrespect that they would never apply to gasoline, as shown by the incidents described below. Another incident was described in Section 12.2 (c). Heavy oils are widely used as fuel oils, solvents, lubricants, and heat transfer oils, as well as process materials. 

Biodiesel does not present any special safety concerns. Pure biodiesel or biodiesel and petroleum diesel blends have a higher flash point than conventional diesel, making them safer to store and handle. Problems can occur with biodiesels in cold weather due to their high viscosity. Biodiesel has a higher degree of unsaturation in the fuel, which can make it vulnerable to oxidation during storage. 

Other important properties include Hash point, volatility, viscosity, specific gravity, cloud point, pour point, and smoke point. Most of these properties are related directly to the boiling range of the kerosene and are not independently variable. The flash point, an index of fire hazard, measures the readiness of a fuel to ignite when exposed to a flame. It is usually mandated by law or government regulation to be 120° or 130° F (48° or 72° C), Volatility, as measured... 

Certain properties of a liquid fuel are measured routinely in a laboratory for characterization purposes. Besides density and viscosity, these properties include the pour point, the cloud point, and the flash point. Standard ASTM (American Society for Testing Materials) procedures are available for their determination. 

The aniline clo d point is a measure of the paraffinicity of a fuel oil. A high value denotes a highly paraffinic oil while a low value indicates an aromatic, a naphthenic, or a highly cracked oil. The flash point represents the temperature to which a liquid fuel can be heated before a flash appears on its surface upon exposure to a test flame under specified conditions. A knowledge of the flash point is needed to ensure safe handling and storage without fire hazards. 

The oil for an oil-base mud can be diesel oil, kerosene, fuel oil, selected crude oil, or mineral oil. There are several requirements for the oil (1) API gravity = 36° - 37°. (2) flash point = 180°F or above, (3) fire point = 200°F or above, and (4) aniline point = 140°F or above. Emulsifiers are more important in oil-base mud than in water-base mud because contamination on the drilling rig is very likely, and it is very detrimental to oil mud. Thinners, on the other hand, are far more important in water-base mud than in oil-base mud oil is dielectric, so there are no interparticle electric forces to be nullified. 

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). 

The temperature at which a fuel will bum continuously when exposed to a flame, as measured in a flash-point apparatus. 

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