Classification of oil. Classes, types, groups, and types of oil.
Qualitative and quantitative composition of the components of oil significantly affects its properties, the quality of the oil produced, and also determines the direction of oil refining. Therefore, the accepted classification of oil on classes, types, groups and types.
Oil is a combustible oily liquid, a mixture of low and high molecular weight hydrocarbon and non-hydrocarbon components. Quantitative and qualitative composition of these components has a significant impact on its properties, the quality of the oil produced, and also determines the direction of the refining of oil.
Therefore, it is the separation of crude oil into classes, types, groups, and types. There are scientific, technological (according to Russia GOST R 51858-2002) and the technical classification of oil.
This scientific classification involving the separation of oil content in their composition of certain classes of hydrocarbons, proposed Grozny petroleum research Institute (of groznii). It is based on the selection in the composition of oil of one or more classes of hydrocarbons that make up the advantage.
Paraffin oil are characterized by the fact that all fractions contain significant amounts of alkanes: petrol fraction – over 50 %, and oil fraction – 20% or more. A number of resinous-asphaltenic substances in them is very little.
Paraffin-naphthenic oil in its composition along with the alkanes in appreciable amounts are also a significant number cycloalkanes (naphthenes). The content of arenes small. A number of resinous-asphaltenic substances in them is very little (as well as in paraffin oil).
For naphthenic oils are characterized by high (up to 60 % or more) content cycloalkanes (naphthenes) in all fractions. The content of alkanes in these oils is not enough. Asphaltenes and resins are available in limited quantities.
Paraffin-naphtene aromatic oil differ approximately the same content of alkanes, naphthenes and aromatic hydrocarbons (arenes). The amount of solid paraffin does not exceed 1-1,5 %. The amount of resinous substances asfaltenovyh reaches 10 %.
Naphtene aromatic oil characterized by the predominant content cycloalkanes (naphthenes), and arenes (aromatic hydrocarbons), particularly in the heavy fractions. Alkanes have only in the light fractions, and in small quantities. The content of solid paraffin does not exceed 0.3 %, while resins and asphaltenes contains 15-20 %.
Aromatic oil is characterized by a high content in all fractions arenes (aromatic hydrocarbons).
Classification of oil by mass fraction of sulphur in the classes entered GOST R 51858-2002 “Oil. General technical conditions”.
Depending on the mass fraction of sulfur in the oil are divided into classes 1 – 4:
|Class of oil||Name||Mass fraction of sulfur, %|
|2||sulfur||from 0.61 to 1.8|
|3||sour||from 1,81 to 3.5|
|4||particularly sour||over 3.5|
Classification of oil density on the types of introduced the GOST R 51858-2002 “Oil. General technical conditions”.
Density, and the export – advanced output fractions and the mass fraction of paraffin oil are divided into five types:
– 0 – a particularly lightweight;
– 1 – easy;
– 2 – average;
– 3 – heavy;
– 4 – bituminous.
|The name of the parameter||
The norm for oil type
|0 (very easy)||1 (easy)||2 (medium)||3 (heavy)**||4 (bituminous)**|
|for Russia||for export||for Russia||for export||for Russia||for export||for Russia||for export||for Russia||for export|
|1. Density, kg/m3, at a temperature of:|
|20 °C||No more 830,0||Of 830.1-850,0||850,1-870,0||870,1-895,0||More 895,0|
|15 °C||No more 833,7||833,8-853,6||853,7-873,5||873,6-898,4||More 898,4|
|2. The yield of fractions, % vol., not less, temperature:|
|3. Mass fraction of paraffin, %, not more||–||6||–||6||–||6||–||–||–||–|
* If the oil on any of the parameters (density or fractions) refers to the type with the lower number, while the other type with a higher number, then the oil is recognized corresponding to the type with a large room.
** Oil types 3 and 4 when used in a pipeline transportation system for further exports should be the norm for the indicator 3 is not more than 6%.
Classification of oil according to the degree of preparation for group introduced the GOST R 51858-2002 “Oil. General technical conditions”.
The degree of preparation of the oil are divided into groups 1-3:
|Name of the indicator||The norm for oil group|
|1. Mass fraction of water, %, not more||0,5||0,5||1,0|
|2. The mass concentration of chloride salts, mg/dm3, not more||100||300||900|
|3. Mass fraction of mechanical impurities, %, not more||0,05|
|4. Saturated vapor pressure, kPa (mm Hg. calendar), not more||66,7 (500)|
|5. Mass fraction of organic chlorides in the fraction boiling to a temperature of 204 0C, million-1 (ppm), not more||10||10||10|
* If one of the indicators of the oil belongs to the group with a lower number, and on the other – to the group with a higher number, then the oil is recognized the corresponding group with a higher number.
Classification of oil by mass fraction of hydrogen sulfide and light mercaptans to the types of introduced the GOST R 51858-2002 “Oil. General technical conditions”.
For the mass fraction of hydrogen sulfide and light mercaptans in the oil are divided into 2 types:
|Name of the indicator||Oil|
|1. Hydrogen sulphide, million-1 (ppm), not more||20||100|
|2. Mass fraction of methyl – and ethylmercaptan in sum, million-1 (ppm), not more||40||100|
The symbol of oil consists of four digits corresponding to symbols of class, type, group and type of oil (given above). For supply of oil for export to the designation of the type is added to the index “a”. The designation of oil:
For example, oil (as delivered to the consumer in Russia) sulphur mass fraction of 1.15% (class 2) density at 20 °C 860,0 (type 2), the concentration of chloride salts 120 mg/cubic DM, the mass fraction of water of 0.40% (group 2), in the absence of hydrogen sulphide (type 1) indicate “184.108.40.206 GOST R 51858-2002”.
Oil (at delivery for export) sulphur mass fraction of 1.15% (class 2) density at 20 °C – 860,0 kg/cubic meter, the volume fraction of fractions up to 200 °C – 26%, up to 300 °C – 46%, up to 350 °C – 55%, the mass fraction of paraffin of 4.1% (type 2E), concentrations of chloride salts 90 mg/cubic DM, the mass fraction of water of 0.40% (group 1), in the absence of hydrogen sulphide (type 1) indicate “2.2 E. 1.1 GOST R 51858-2002”.
The content of paraffin hydrocarbons of the oil are divided into 3 types:
|Oil||Name||The amount of paraffin hydrocarbons, %|
|P1||Malopurginsky||not more than 1.5|
|P2||Paraffin||from 1.5 to 6|
* This classification is a technical one.
The yield of light fractions up to 350 °C, the oil is divided into three types:
|Type of oil||The light fraction yield, %|
|T1||not less than 45|
|T2||of 30.0 to 44.9|
|T3||less than 30|
* This classification is a technical one.
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