Oil, chemical composition, properties and application.
Fuel oil is a flammable viscous liquid, a combustible fuel. Represents the balance after allocation of the oil or its products recyclable gasoline, kerosene and gas oil fractions boiling up to 350-360 °C.
Fuel oil (Arabic for “meshulach” – “dregs”) is a liquid product of dark brown or black. Fuel oil is a flammable viscous liquid, combustible fuel.
Fuel oil is a residue after separation of oil or products of its recycling gasoline, kerosene and gas oil fractions boiling up to 350-360 °C. fuel oil produced from coal and oil shale, however production is developed in small volumes.
The main indicator of oil quality if labelling is the viscosity, which determines conditions for draining and filling tanks, tank cars, tankers and other containers, transportation of oil by pipeline, feeding it into the combustion space of the furnace, etc. Viscosity of fuel oil is estimated in units of relative viscosity (°WU) and determined by the ratio of time of expiration 200 ml of oil at a given temperature to the time of expiration of the same volume of distilled water at 20 °C. the viscosity of the oil depends on the temperature, density and colistete. At low temperatures the viscosity of fuel oil increases significantly, so draining it from the tanks and transfer piping may be conducted only after pre-heating fuel.
The density of the oil is in the range of 0.89-1.02 g/cm3 and increases with viscosity. The lower the density of the oil, the easier and faster it is separated from water and mechanical impurities.
Fuel oil has a high polluting properties. The combustion of oil in the open space a significant amount of black soot, which is detrimental to the environment and toxic to humans.
Fuel oil in its chemical composition is a mixture of various hydrocarbon and non-hydrocarbon components:
– hydrocarbons with a molecular weight of from 400 to 1000 g/mol,
– petroleum resins with a molecular weight of from 500 to 3000 or more g/mol,
– organic compounds containing metals (vanadium V, Nickel Ni, iron Fe, magnesium Mg, sodium Na, calcium Ca).
Physico-chemical properties of the oil depend on the chemical composition of the original oil and the degree of refining of distillate of distillate fractions.
The following table shows the elemental composition of fuel oil:
|The name of a chemical element:||%% content|
|Nitrogen and oxygen, N + O||0,2-1,9|
|and other impurities (including water and mechanical impurities)|
In accordance with GOST 10585-2013 “Fuel oil. Oil. Technical conditions” depending on the purpose, the following brands of oil:
– flue 40,
– the furnace 100.
Designation of the fuel oil includes:
– for fuel oil bunker – brand and mass fraction of sulfur. For example, bunker fuel oil F5, at 1.50% according to GOST 10585-2013,
– for fuel oil furnace – brand, mass fraction of sulphur, ash content and pour point. For example, a fuel oil 100, 2,00%, low ash, 25 °C according to GOST 10585-2013.
The level of sulfur in fuel oil is divided into low-sulfur no more than 0,5% of sulphur, sulphur – to 1% and sulphur up to 3.5 %.
GOST 10585-2013 “Fuel oil. Oil. Technical conditions”, the following requirements for physico-chemical parameters of oil:
|Name of the indicator||The value for the brand|
|naval F5||furnace 40||furnace 100|
|Kinematic viscosity, mm2/s, max:|
|at 50 °C||36,20||–||–|
|at 80 °C||–||59,00||–|
|at 100 °C||–||–||50,00|
|viscosity at 100 °C, C WU, no more||–||–||Of 6.80|
|Ash content, %, max for fuel oil:|
|Mass fraction of mechanical impurities, %, not more||0,10||0,5||1,0|
|Mass fraction of water, %, not more||0,3||1,0||1,0|
|The content of water-soluble acids and alkalis||The lack of|
|Mass fraction of sulfur, %, not more|
|1,50||Of 1.00||Of 1.00|
|Of 2.00||Of 2.00|
|Of 3.00||Of 3.00|
|Coking ability, %, not more||6,00||–||–|
|Hydrogen sulfide, ppm (mg/kg), not more||10||10|
|Flash point, °C, not below:|
|in open crucible||–||90||110|
|Pour point, °C, not above||Minus 5||10||25|
|for fuel oil from waxy oil||–||25||42|
|The heat of combustion (lowest) in recalculation on dry fuel (narakaloka), kJ/kg, not less, for fuel oil with content of sulphur, %:||41454|
|0,50, 1,00, 1,50, 2,00||–||40740||40530|
|2,50, 3,00, 3,50||39900||39900|
|Density at 15 °C, kg/m3, not more||958,3||Not regulated. Definition of necessary|
|The yield of fraction boiling up to 350°C, % vol., no more||22||17||17|
|Color||dark brown or black|
|The smell||a faint smell of oil|
|Density of fuel oil (at 20 °C and atmospheric pressure of 1 ATM.) kg/m3||890-1020|
|The viscosity of oil (mm2/s (at 100 °C)||8-80|
|Pour point of fuel oil*, °C||from -5 to 42 (depending on brand)|
|The ignition temperature of the fuel oil**, °C||from 91 to 155|
|The ignition temperature of oil, °C||about 350|
|The flash point of fuel oil***, °C||from 80 to 112|
|Explosive concentrations of vapor mixture of fuel oil with air, % by volume||from 1.4 to 8|
|Specific heat of combustion, MJ/kg||39,9-41,4|
* – pour point is the temperature at which the oil loses mobility in test conditions. Pour point consider the temperature at which the oil level in the standard flat-bottomed test tube when it is tilted at 45° does not change its position for 1 minute;
** – the ignition temperature is the temperature of a combustible substance that releases flammable vapours and gases with such speed that after ignition from the ignition source occurs steady burning;
*** – flash call this the temperature at which the vapors of oil and form with the surrounding air mixture, flashing in the presentation to her of the fire.
Fuel oils are used as fuel for steam boilers, boiler plants and industrial furnaces, in engines of ships and locomotives. Oil is a valuable raw material for the chemical industry.
– gas oil,
– oil shale,
– fuel oil,
– associated petroleum gas,
– natural gas,
– landfill gas,
– shale oil,
– shale gas,
– synthesis gas.
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