Mazut is the kind of petroleum fuel oil used as a boiler fuel in power generation, shipping and industry. Mazut is used as boiler fuel for various heat generators as the main source of thermal energy in heating systems, boilers. Fuel oils include mazuts of grades 40 and 100. The specifications of mazuts are standardized according to GOST 10585-99.
Furnace fuel oil is intended for burning in heating systems of small capacity, in the living quarters, as well as in heat-generator of the average power used in agriculture to feed preparation, drying grain, fruit, conservation and other purposes.
Requirements, defined the quality of boilers, heavy motor and marine fuels, establishing conditions for their use are determined by quality index, such as viscosity, sulfur content, heating value, and flash point, freezing temperature, water content, solids and ash content.
Standard for fuel oil - GOST 10585-99 provides for the production of four grades: bunker fuel F-5 and F-12, which is classified as light viscosity fuel, fuel oil of grade 40 as the average grade and grade 100 as the heavy fuel. The numbers indicate the approximate viscosity of appropriate grades of fuel oil at 50 ° C.
Fuel oils of grades 40 and 100 are made from residues of petroleum refining. In the fuel oil of grade 40 to lower the freezing temperature to 10 ° C., it is added 8-15% middle- distillate fractions; in the fuel oil of grade 100 of diesel fraction it isn’t added. Bunker oil of grades F-5 and F-12 is used for burning in ship power plants. Compared with furnace fuel oil of grades 40 and 100 they have better characteristics: lower viscosity, solid and water, ash and a low pour point.
Bunker oil of grade F-5 is made by mixing the products of direct distillation: in the most cases, 60-70% is oil and 30-40% is of straight diesel fuel with added depressant. It may be used in its compound up to 22% of kerosene-gas oil fractions of secondary processes, including light gas oil catalytic and thermal cracking. Bunker oil of grade F-12 is produced in small quantities in plants straight distillation of crude oil. The main differences between the fuel oil F-12 from the fuel oil F-5 are more stringent requirements for sulfur content (0.6% vs. 2.0%) and less stringent requirements for the viscosity at 50 ° C (12 °E vs. 5 ° E).