Martin, C. J.
Martin and Associates, Fort Washington, MD
Defense Energy Support Center, Fort Belvoir, VA
Pages: 15 Published: Jan 2010
ALTHOUGH MOST PETROLEUM PRODUCTS CAN BE used as fuels, the term “fuel oil,” if used without qualification, may be interpreted differently in various countries. For example, in Europe, fuel oil generally is associated with the black, viscous, residual material that remains as the result of refinery distillation of crude oil, either alone or in a blend with lighter components, and it is used for steam generation for large slow-speed diesel engine operation and industrial heating and processing. In the United States, the term “fuel oil” is applied to both residual and middle distillate type products, such as domestic heating oil, kerosine, and burner fuel oils. Because fuel oils are complex mixtures of compounds of carbon and hydrogen, they cannot be classified rigidly or defined exactly by chemical formulas or definite physical properties. For purposes of this chapter, the term “fuel oil” will include all petroleum oils heavier than gasoline that is used in burners. Because of the wide variety of petroleum fuel oils, the arbitrary divisions or classifications, which have become widely accepted in industry, are based more on their application than on their chemical or physical properties. Thus, it is not uncommon to find large variations in properties among petroleum products sold on the market for the same purpose. However, two broad classifications are generally recognized: (1) “distillate” fuel oils and (2) “residual” fuel oils. The latter are often referred to as heavy fuel oils and may contain cutter stock or distillates. Middle distillate fuel oils are petroleum fractions that have been vaporized and condensed. They are produced in the refinery by a distillation process in which petroleum is separated into fractions, according to their boiling range. These middle distillate fuel oils may be produced not only directly from crude oil, that is, “straight-run,” but also from subsequent refinery conversion processes, such as thermal or catalytic cracking. Domestic heating oils and kerosine are examples of middle distillate fuel oils. Common terms for the lighter (distillate) products include range oil, stove oil, and furnace oil, with range and stove oil being the lighter of the products.
Paper ID: MNL11646M