Basic raw materials for the petrochemical industry

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Basic raw materials for the petrochemical industry There are 4 categories of basic raw materials for the petrochemical industry: alkynes (ethylene, propylene, butylenes, and butadiene), aromatics (benzene, toluene, xylene), and syngas. From these basic raw materials, various important organic chemical products and synthetic materials can be produced. Natural gas chemistry; Classification of refineries: They can be divided into 4 types. 1) Fuel oil type is used to produce gasoline, kerosene, light and heavy diesel, and boiler fuel. 2) The fuel-lubricant type not only produces various fuel oils but also various lubricants. 3) The fuel chemical type is mainly focused on producing fuel oil and chemical products. 4) Fuel, lubricant, and chemical type: This is a comprehensive refinery that produces various fuels, chemical raw materials or products, as well as lubricants. ? Crude oil evaluation tests: Before processing a crude oil, it is necessary to determine its color and odor, boiling point and boiling range, density, viscosity, freezing point, flash point, ignition point, auto-ignition point, residue, sulfur content, and other parameters – these are the crude oil evaluation tests. Dividing the crude oil into several different boiling range categories (i.e., fractions) is referred to as primary processing ； Reprocessing the fraction obtained in the first stage into commercial oil is called secondary processing ； The process of converting the refined commercial oil into basic organic chemical raw materials is called tertiary processing. One-time processing device ； Atmospheric distillation or atmospheric-vacuum distillation. Secondary processing units: catalysis, hydrocracking, delayed coking, catalytic reforming, alkylation, hydrorefining, etc. Third-stage processing unit: The pyrolysis process is used to produce chemical raw materials such as ethylene and aromatics. ? Octane rating The octane rating is an indicator of a gasoline’s resistance to knocking when it burns in an internal combustion engine. The standard octane value of normal octane is specified as 100, while that of n-heptane is set at zero. By mixing these two standard fuels in various volume ratios, mixtures with different anti-knock properties can be obtained, which are then compared with the fuel under test under the same operating conditions as the engine. The octane number of a sample is the percentage of isooctane contained in the mixture with the same seismic resistance as that sample. Gasoline has a high octane rating, good resistance to shock, and excellent quality. 　　Cetane number is an indicator of the auto-ignition property of diesel when it burns in a diesel engine. The cetane number of pure hexadecane is usually set at 100, while that of pure methylnaphthalene is set at zero. By mixing them in different proportions, standard fuels with cetane numbers ranging from 0 to 100 and varying levels of anti-knock properties can be obtained, which are then compared with the diesel fuel under test on a single-cylinder testing machine of a specific design. The main chemical reactions in catalytic cracking are as follows. The primary feedstock for hydrocracking is heavy distillates, including catalyst cracking cycle oil and coking distillates. Its products are mainly high-quality light oils, particularly high-quality aviation kerosene and diesel with low freezing points. Domestic and international dewaxing processes include cold pressing dewaxing, mixed solvent dewaxing, molecular sieve dewaxing, urea dewaxing, bacterial dewaxing, catalytic hydrodesulfurization for viscosity reduction, and spray dewaxing. ? Uses of butylene 　　Butylene is primarily used to produce high-octane gasoline components through blending, accounting for about 60% of its total consumption. Another 11% of blended butylene is used as industrial or domestic fuel. Butylene used as a raw material in the petrochemical industry accounts for only 29% of total butylene consumption; n-butylene is primarily used in the production of butadiene, while the rest is used to manufacture maleic anhydride, sec-butanol, heptene, polybutylene, acetic anhydride, and other substances. ? Uses of butadiene Butadiene is an important monomer for synthesizing rubber and synthetic resins. Since dienes can be used to produce cis-butadiene rubber, styrene-butadiene rubber, nitrile rubber, and neoprene, they can also be used to manufacture resins such as polybutadiene, ABS, and BS. In addition, butanediol and hexamethylenediamine (a monomer for nylon) can also be produced. The purpose is to remove undesirable components from the lubricating oil, improve its antioxidant stability, enhance its viscosity-temperature properties and color, and reduce its acid value and carbon residue value. Status: Phenol refining is an important manufacturing process in lubricant production. The vacuum second, third, and fourth fractions obtained from distillation, along with the residue oils from propane deasphalting, are first refined using phenol, then dewaxed, further refined, and blended to produce finished lubricating oils. Therefore, phenol refining plays a very important role in the production of lubricants at refineries. ? Types of fluid flow rate and velocity The flow rate and velocity of fluids can be divided into mass flow rate and mass velocity, as well as volume flow rate and volume velocity. Mass flow rate is the mass of fluid that passes through any cross-section of a pipe or device per unit of time. Mass flow rate is usually denoted by the symbol G, with the unit of kg/s. Volumetric flow rate is the volume of fluid that passes through any cross-section of a pipe or device per unit of time. Volumetric flow rate is usually denoted by the symbol V, with the unit of m3/s. Mass flow rate is the mass of fluid that passes through a unit cross-section of a pipe or device per unit of time. It is usually denoted by the symbol WG, with the unit of kg/s•m2. Volumetric flow rate is the volume of fluid that passes through a unit cross-section of a pipe or device per unit of time. Volumetric flow rate is usually denoted by the symbol WV, with units of m3/s•m2 or m/s. Density, specific gravity The weight of a material per unit volume is called density, with the unit being kg/m3. The mass of matter per unit volume is called density, with the unit being g/cm3. Specific gravity refers to the ratio of the weight of a substance to the weight of an equal volume of pure water at 4°C. The specific gravity of a liquid is the ratio of the weight of a volume of that liquid to the weight of water, and it is a value without units. Viscosity: When a fluid is in motion, there is relative movement between adjacent layers of the fluid, and frictional resistance arises between these layers; this resistance is known as viscous force. Viscosity is a physical property used to measure the magnitude of viscosity. Viscosity includes dynamic viscosity, whose unit is Pascal-second (Pa•s) ； Dynamic viscosity, in engineering calculations, is the ratio of a substance’s dynamic viscosity to its density, and its unit is: (m2/s). Engler viscosity is also used in the petroleum industry; it is not the concept of viscosity mentioned above. Rather, it is the direct reading of the fluid’s viscosity at Engler. ? The current grades of gasoline for vehicles include premium grade, first-grade, and qualified grade. The grades are 10#, 0#-10#, -20#, -35#, and -50#. ? Technical indicators for enterprise energy balance The petrochemical industry, abbreviated as petrochemistry, is an important part of the chemical industry and plays a significant role in the development of the national economy; it is one of the key industrial sectors in China. The petrochemical industry refers to the processing industry that uses oil and natural gas as raw materials to produce petroleum products and petrochemical products. Petroleum products, also known as oils, mainly include various fuel oils (gasoline, kerosene, diesel, etc.), lubricants, as well as liquefied petroleum gas, petroleum coke, paraffin, asphalt, and others. The processing process for producing these products is often referred to as petroleum refining, or simply refining. Petrochemical products are obtained through further chemical processing of the crude oil supplied by the refining process. The first step in producing petrochemical products is the cracking of crude oil and gases (such as propane, gasoline, diesel, etc.) to generate basic chemical raw materials represented by ethylene, propylene, butadiene, benzene, toluene, and xylene. The second step is to produce a variety of organic chemical raw materials (about 200 types) and synthetic materials from basic chemical raw materials