Kerosene cloud point

Pour point ranges from 213 K (—80°F) for some kerosene-type jet fuels to 319 K (115°F) for waxy No. 6 fuel oils. Cloud point (which is not measured on opaque fuels) is typically 3 to 8 K higher than pour point unless the pour has been depressed by additives. Typical petroleum fuels are practically newtonian liqmds between the cloua point and the boiling point and at pressures below 6.9 MPa (1000 psia). 

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... 

It is possible to dilute diesel fuel such as 2-D low sulfur with kerosene, 1 fuel oil, or jet fuel to reduce the fuel cloud point. Also, additives are also marketed which have the ability to inhibit nucleation of wax crystals in some fuels, thereby lowering the cloud point of the fuel. These products are called cloud point improvers. 

The use of kerosene or 1 fuel oil in reducing the cloud point of distillate fuel is common practice. By diluting the fuel with these lighter streams, wax-related problems can be minimized, but not eliminated. As a general rule a reduction in... 

FIGURE 4-5. Effect of Kerosene Blending on the Cloud Point of Low-Sulfur... 

During winter and under other low-temperature operating conditions, fuel cannot be effectively filtered at temperatures much below its cloud point unless the fuel wax is diluted with kerosene or treated with a wax crystal modifier. 

Different steps are taken to prevent and avoid this situation. Utilization of low-cloud-point diesel fuel and blending with kerosene are two possible solutions. Sometimes these measures are viewed as costly and impractical. 

Lowering the cloud point and pour point values of a distillate fuel can be accomplished by blending the fuel with a low-wax-content distillate stream such as a kerosene or jet fuel. Also, additives are frequently used in conjunction with kerosene blending or as a substitute for kerosene blending to reduce the pour point of diesel fuel. Additives are not as frequently used to reduce the cloud point of diesel fuel. 

Commercial value of a petroleum liquid can be estimated quickly through measurement of the following physical characteristics . specific gravity, gasoline and kerosene content, sulfur content, asphalt content, pour point, and cloud point. 

The essential properties of kerosene are flash point (ASTM D-56, ASTM D-93, ASTM D-3828, IP 34, IP 170, IP 303), distillation range (ASTM D86, ASTM D-1160, ASTM D-2887, ASTM D-6352), burning characteristics (ASTM D-187, IP 10), sulfur content (ASTM D-129, ASTM D-2622, ASTM D-3120, ASTM D-3246, ASTM D-4294, ASTM D-5453, ASTM D-5623, IP 61, IP 336, IP 373), color (ASTM D-156, ASTM D-1209, ASTM D-1500, ASTM D-1554, ASTM D-2392, ASTM D-3830, ASTM D-6045), and cloud point (ASTM D-2500, ASTM D-5772, ASTM D-5771, ASTM D-5773, IP 219). In the case of the flash point (ASTM D-56), the minimum flash temperature is generally placed above the prevailing ambient temperature the fire point (ASTM D-92) determines the hre hazard associated with its handling and use. 

The color of kerosene is of little significance, but a product darker than usual may have resulted from a change in composition because of contamination or aging and in fact a color darker than specihed (ASTM D-156) may be considered by some users as unsatisfactory. Finally, the cloud point of kerosene (ASTM D-2500) gives an indication of the temperature at which the wick may become coated with wax particles, thus lowering the burning qualities of the oil. 

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