Fuel oil is a dark-brown liquid hydrocarbon product. The heavy residue after distillation of petrol, kerosene and gas oil fractions boiling down to 350-360 ° C from oil or products of its secondary processing. Fuel oil is a hodgepodge of hydrocarbons with a molecular weight of from 400 to 1000 g / mol, oil resins with a molecular weight of 500-3000 or more g / mol, asphaltenes, carbides, carbenes, and organic compounds containing metals (V, Ni, Fe , Mg, Na, Ca).
The physico-chemical properties of fuel oil depend on the chemical composition of the original oil and the degree of distillation of distillate fractions.
The use of fuel oil. The main consumers of fuel oil are industry, fleet and housing. Fuel oil is used as fuel for steam boilers, boiler houses, and industrial furnaces, for the production of heavy fuel oil, heavy motor fuel for crosshead diesel engines and bunker fuel. The share of fuel oil is about 50% by weight of the initial mass of oil. To deepen the processing of fuel oil, distillates distilled under vacuum at 350–420, 350–460, 350–500, and 420–500 ° C are distilled off under vacuum. The residue of vacuum distillation of fuel oil is used for processing at thermal cracking and coking plants, in the production of lubricating oils and tar, then processed into bitumen.
Vacuum distillates are used as raw materials for the production of motor fuels, in hydrocracking, catalytic cracking, and distillate lubricating oils.