How is crude oil classified?

Fuel oils with viscosities of 120cst, 180cst, and 380cst are *traditional names used internationally from after 1977 until international standards for marine fuel oils were established, with the dynamic viscosity at 50°C serving as an indicator of the fuel oil grade; they are sometimes also denoted as IF-120, IF-180, IF-380, or simply referred to as 120# fuel oil, 180# fuel oil, and 380# fuel oil.

Crude oil can be referred to as Zhongyuan crude, Shengli crude, Daqing crude, Tahe crude, Karamay crude, Liaohe Tuozi crude, Harbin crude, Russian crude, and so on; however, it is not classified in this way! 1. Classification by characteristic factor: paraffin-based, intermediate-based, naphthenic-based. 2. Classification by density: light oil, medium oil, heavy oil, ultra-heavy oil. 3. Sulfur content: low-sulfur oil, sulfur-containing oil, high-sulfur oil. 4. Classification by acid value: low-acid oil, acid-containing oil

Crude oil is classified mainly in industrial and chemical terms. The industrial classification includes: 1) by density: light oil with a density of 0.884, and heavy oil with a density greater than 1; 2) by sulfur content: low-sulfur oil with 2.0% sulfur; 3) by wax content: low-wax oil with 0.5–2.5% wax, medium-wax oil with 2.5–10% wax, and high-wax oil with more than 10% wax. There are two types of chemical classification. The characteristic factor and key component methods are commonly used in the evaluation of crude oil. However, in practice, the classification is not always based on these methods; geological classification is also taken into account

Thank you for your answers. So what category does M100 fall into?

Methods for classifying crude oil include: by origin – Daqing crude oil, Tahe crude oil, etc.; by sulfur content – low-sulfur crude oil, sulfur-containing crude oil, high-sulfur crude oil; by density – light crude oil, medium crude oil, heavy crude oil, super-heavy crude oil; by characteristic factors – paraffinic-based, intermediate-based, naphthenic-based; by acid value – low-acid crude oil, acid-containing crude oil, high-acid crude oil. 380 is a type of fuel oil, and its grade is indicated by its kinematic viscosity at 50°C. M100 is also a straight-run fuel oil produced in Russia; its technical specifications are as follows: kinematic viscosity at 50°C of 100, ash content not exceeding 6.8%, mechanical impurities not exceeding 0.1%, water content not exceeding 1.0%, sulfur content not exceeding 1.0%, open flash point not exceeding 110°C, freezing point not lower than 110°C, calorific value not exceeding 42 Kkal/kg, density of 0.890–0.930, and carbon residue of 7%. This post was last edited by jinzi1973 on 2009-2-14 17:39.]

1. Classify by place name, oil field, or ** to determine the source or origin, such as Daqing, Shengli, Tahe, Tarim, Zhongyuan, etc., as well as crude oil from the Middle East and other foreign regions. . . 2. By sulfur content: low-sulfur crude oil, sulfur-containing crude oil, high-sulfur crude oil. 3. By density: light crude oil, medium crude oil, heavy crude oil, ultra-heavy crude oil. 4. Classified by characteristic factor: paraffinic, intermediate, naphthenic. 5. By acid value: low-acid crude oil, acid-containing crude oil, high-acid crude oil. 6. By viscosity: low viscosity, normal viscosity, high viscosity. . . 7. Classified by wax content: low wax 0.5–2.5%, medium wax 2.5–10%, high wax >10%. 8. 380 is a type of fuel oil; its grade is determined by its dynamic viscosity at 50°C, which is 380. 9. M100 is also a type of straight-run fuel oil, produced in Russia; its key technical parameter is a dynamic viscosity of 100 at 50°C. Generally, a classification based on characteristic factors is used: it is divided into paraffin-based, intermediate-based, and naphthenic-based types. Additionally, those that can be classified as either intermediate-based or naphthenic-based can be further subdivided into intermediate-naphthenic and naphtheno-intermediate: lol

Crude oil classification The properties of crude oil vary depending on its origin. In the early days, people classified petroleum into three categories based on the properties of its distillation residues: paraffinic-based, asphaltic-based (also known as naphthenic-based), and mixed-based (also known as intermediate-based). Later, as further understanding was gained regarding the properties and composition of petroleum, many classification systems were proposed based on these properties, composition, or product quality, such as those that use characteristic factors (calculated from the average boiling point and relative density of petroleum) as indicators. However, due to the complex composition of oil, oils within the same category can still differ significantly in their properties. Therefore, there has been no unified standard classification system to date.

The answer on floor 7 was helpful to me; thank you

Thank you so much. Now I understand what’s going on

The composition of crude oil is extremely complex, making it difficult to accurately classify it. The differences in the properties of crude oil lie mainly in their chemical composition; therefore, a chemical classification method is generally preferred. However, for practical purposes, a commercial classification method is sometimes also used. The chemical classification of crude oil is based on its chemical composition; however, since analyzing the chemical composition of crude oil is complex, several physical properties of crude oil that are directly related to its chemical composition are usually used as the basis for classification. In the chemical classification of crude oil, the most commonly used methods are the characteristic factor classification and the key fraction characteristics classification. Based on the value of the characteristic factor (K), crude oils are divided into three categories: Crude oils with a characteristic factor K greater than 12.1 are classified as paraffinic crude oils; those with a K value of 11.5–12.1 are considered intermediate-base crude oils; and those with a K value of 10.5–11.5 are classified as naphthenic crude oils. Paraffinic crude oils generally have an alkane content of over 50%, and they are characterized by low density, high freezing points, and low levels of sulfur and gums. Naphthenic crude oils generally have a high density and a low freezing point. The properties of intermediate base crude oil lie between those of the two mentioned above. The commodity classification method for crude oil can serve as a supplement to the chemical classification method, and it also has certain practical value in industry. The criteria for classification include: classification by density, classification by sulfur content, classification by wax content, classification by gum content, etc. A unit established by the American Petroleum Institute (API) to indicate the density of petroleum and petroleum products. The United States and China use the API degree as a benchmark for classifying crude oil (see Crude Oil Evaluation). Its standard temperature is 15.6°C (60°F), and its API grade, which relates to the relative density at 15.6°C (compared to water), is an index of a liquid’s specific gravity used to indicate its relative density. API=141.5/d15.615.6-131.5. As can be seen from the above formula, the higher the API value, the lower the relative density. Currently, the API degree is regarded internationally as one of the main criteria for determining crude oil prices. The higher its value, the lighter the crude oil and the higher its price. ①Classified by crude oil density: Light crude oil >34°API ； ＜852 kg/m3 (20°C) Medium-grade crude oil 34–20°API ； 852–930 kg/m3 (20°C) Heavy crude oil 20–10°API ； 931–998 kg/m3 (20°C) Very heavy crude oil <10°API ； ＞998 kg/m3 (20°C) ② Classification by sulfur content in crude oil: Low-sulfur crude oil – sulfur content < 0.5%; Sulfur-containing crude oil – sulfur content 0.5%–2.0%; High-sulfur crude oil – sulfur content > 2.0%. However, different countries establish their own criteria based on the properties of the crude oil used there, so the values listed above can be regarded as reference standards only. ③Classification by wax content: Generally, a fraction is extracted from petroleum with a viscosity of 53 mm2/s at 50°C, and then its freezing point is measured. When the freezing point is below -6°C, it is called low-wax crude oil; when the freezing point is between -15°C and 20°C, it is called wax-containing crude oil ； When the freezing point is greater than 21°C, it is called a waxy crude oil. Classification by wax content: Low-wax crude oil – wax content of 0.5%–2.5%; Medium-wax crude oil – wax content of 2.5%–10%; High-wax crude oil – wax content >10%. ④ Classification by resin content is based on the resin content in heavy oil (fractions with a boiling point above 300°C). Crude oil with a gum content of less than 17% is referred to as low-gum crude oil ； Crude oil with a resin content of 18% to 35% is referred to as resinous crude oil ； Crude oil with a gum content of 35% or more is referred to as high-gum crude oil.