Straight-run diesel refers to a middle distillate having a boiling range of from 180 °C to 360 ° C obtained by atmospheric distillation after pretreatment of crude oil. According to the order from the side line of the atmospheric tower, it can be further divided into a constant line, a constant line, and a constant line.
Straight-run diesel has a high cetane number and contains a lot of naphthenic acid, which must be deacidified and refined before it can be used as a diesel blending component.
- Coking diesel
Coking diesel refers to a fraction product having a boiling range of 180 °C to 360 °C obtained by delayed coking. Coking diesel has a high cetane number and contains a certain amount of sulfur, nitrogen and metal impurities. It contains a certain amount of olefins, has poor oxidation stability, high gel content and high chroma. It must be refined to remove sulfur and nitrogen. Impurities, so that olefins, aromatics can be saturated to be a qualified diesel fraction.
- Viscosity-reducing diesel
The viscous diesel oil is a middle distillate product obtained by visbreaking. The viscous diesel oil contains olefins and diolefins, so the stability is poor, and it needs to be hydrotreated to be used as a diesel blending component.
- Catalytic cracking diesel
Catalytic cracking diesel is commonly known as firewood and is a middle distillate product obtained by catalytic cracking. Because of the high content of aromatic hydrocarbons, the cetane number is lower than that of straight-run diesel. The diesel fuel obtained by catalytic cracking of heavy oil has a lower cetane number of only 25-35, and the stability is very poor. Hydrogen treatment, or blending with good quality straight-run diesel to meet the quality requirements of light diesel.
Hydrocracking diesel refers to the middle distillate obtained by hydrocracking. Its sulfur content is very low, less than 0.01%, the aromatic content is also low, cetane number is greater than 60, the ignition performance is good, the stability is high, and the blending is low. The ideal component for diesel fuels for sulfur vehicles.
- Reduce the oil
The minus one line oil refers to the lightest fraction which is discharged from the side of the vacuum tower by vacuum distillation after pretreatment of the crude oil. Because its physical and chemical properties such as density and viscosity are similar to those of diesel, it is also used as a diesel blending component.
- Aviation kerosene
Aviation kerosene generally refers to No. 3 jet fuel, with a standard density of 775-830kg/m3 and a distillation range of 160-300°C. The low-temperature fluidity is good, the freezing point is below -47°C, and the distillation range is close to diesel, which is often low in winter. The blending component of the diesel fuel, but with a slightly lower cetane number, is also required to be added to the diesel fuel to meet the quality requirements.
8.200# solvent oil
200# Solvent oil is a petroleum fraction component from 140 ° C to 200 ° C, which is commonly used as a solvent for paints and cleaning in the industry. The density of 200# solvent oil is smaller than that of diesel oil, and it has good low-temperature fluidity. It is often used as a diesel blending component to reduce density and improve low-temperature fluidity, but its cetane number is very low, so it is necessary to control the addition amount without affecting the quality of diesel.
- Heavy aromatics
Heavy aromatic hydrocarbons refer to mixed aromatic hydrocarbons with a molecular weight greater than xylene, most of which are carbon nine or carbonarene, mainly derived from reformated aromatic hydrocarbons, cracked aromatic hydrocarbons and coal tar. It can be used as a blending component to reduce the freezing point and cold filter point of diesel fuel. However, because its main component is aromatic hydrocarbon, the cetane number is extremely low, and it is necessary to add a cetane number improver to meet the quality requirements.
- Coal tar hydrogenated diesel
Coal tar is a by-product of coal processing-coking and coal gasification processes. Clean gasoline and diesel fractions can be obtained through hydrodeionization, hydrorefining and hydrotreating processes. The obtained diesel component has a density of 0.85 to 0.89, a sulfur content of less than 10 ppm, and a cetane number of 30 to 40.
- Waste motor oil refining diesel
The waste engine oil is dehydrated and decomposed, cracked under the catalyst and high temperature, then refined by acid and alkali, refined by white clay, and finally distilled to obtain the corresponding product. The diesel oil has a cetane number of 40, but the fraction is heavy and smells bad. It is generally required to be deodorized before use.
- Waste plastics refining diesel
Dispose of discarded PE (polyethylene), PP (polypropylene), PS (polypropylene) and other waste plastics, remove the impurities, break into the cracking furnace, crack at the catalyst and high temperature (350 ~ 420 ° C), and finally obtain the corresponding distillation product. The cetane number of diesel produced from waste plastics can meet the requirements of national standard diesel, and the freezing point is also low. However, because of high olefin content, stability and poorness, it is highly susceptible to oxidative discoloration.
- Coal to oil
Coal-to-liquid is essentially a coal liquefaction technology that converts the hydrocarbons contained in coal into the desired hydrocarbons through chemical reactions. According to different processing routes, it can be divided into two categories: direct liquefaction and indirect liquefaction.
Direct coal liquefaction is the conversion of coal into liquid fuel by hydrogenation under high temperature and high pressure conditions. The typical representative is Shenhua Group coal-to-liquid. The direct liquefaction is characterized by high yield of liquefied oil and high content of aromatics in oil, and the produced cetane number of diesel is not higher than 45.