Consultation, design, and construction of paraffin production units
Petro Sanat Hoorasia Company specializes in the design and construction of paraffin production plants in industrial ranges. Liquid paraffin (also known as liquid paraffin wax) or mineral oil, commonly referred to as white oil, is derived from the distillation of petroleum derivatives and is refined and purified. This oil is white or clear in color, boils at 175°C, and evaporates at 265°C. Additionally, mineral oil is viscous and does not exhibit fluorescent properties; meaning it does not shine due to external factors such as heat and radiation.
Industrial Liquid Paraffin: This type of mineral oil, also known as kerosene, white oil, furnace oil, and lamp oil, contains more impurities compared to the hygienic variety and has a smell similar to diesel. It is used for lubricating industrial machinery.
Production Process of White Liquid Paraffin:
Production of Isocyclohexane from crude oil entering the refinery: Crude oil, after entering the refinery, undergoes dehydration and salt removal operations. After preparation, the heated crude oil enters the Tower Atmospheric. In this tower, light materials such as methane, ethane, propane, butane, and heavier materials such as Light and Heavy Naphtha, Blending Naphtha, White Oil, and Light Gasoil are separated. After separating the materials in the tower, the heaviest output from the bottom of the tower, called the Atmospheric Residue, is heated and enters another tower called the Tower Vacuum. In this tower, substances like Heavy Gasoil, Lube Cut, Iso Feed, etc., are separated. The Iso Feed enters the Hydrocracker Iso Max unit, where it undergoes molecular cracking and isomerization at approximately 190 bar pressure and 400°C in the presence of a catalyst and hydrogen. This results in middle distillates. During this process, a byproduct called Recycle Iso is produced. This is a mixture of paraffin and light wax, which, when passed through the wax removal unit, separates the paraffin from the light linear wax.
De-waxing: Isocyclohexane is used to separate light slack wax from industrial liquid paraffin. (It should be noted that isocyclohexane is a mixture of paraffinic and isoparaffinic molecules with a small percentage of aromatic compounds, produced by catalytic cracking in the presence of hydrogen).
This unit consists of the following sections: A- Solvent and feed mixing section B- Cooling section C- Filtration section D- Solvent recovery section E- Compressor section
Aromatic Dehydrogenation for the Production of White Liquid Paraffin from Industrial Liquid Paraffin: For certain applications such as food and hygiene purposes, aromatic dehydrogenation is carried out more intensively, while for other purposes like pest control, textiles, and so on, it is done less intensely. In the standard method, liquid paraffin is mixed with a special solvent and then in sedimentation tanks, the high-aromatic phase and solvent are separated from the low-aromatic phase. The solvent is recovered by distillation and returned to the production cycle. The upper low-aromatic phase, after being solvent-free, is sent to the acid washing unit, where the remaining aromatics are converted into sulfonic acid when exposed to sulfuric acid. This by-product is used in the production of mold oil and soap water. The acid-washed product is sent to sedimentation tanks for sulfonic acid separation. After separating the denser sulfonic acids, which settle at the bottom of the tank, the upper phase is sent for final neutralization and color removal with toncil or bentonite in a reactor with heating and stirring. Finally, filtration with a filter press completes the process.
The role of the filter press in the paraffin distillation and cooling process:
Paraffin oil compounds are distilled from petroleum at a temperature lower than about 860°F (460°C). This process can allow the oil to be filtered through simple filter presses. In crude oil fractions, “raffinate” or the cut defined as the paraffin distillation process boils between 170°C to 310°C (338°F to 590°F) at very low pressure. This process can turn into solid paraffin and liquid oil when cooled. Simple filter presses are responsible for carrying out this critical function.
The solid fraction, which contains 65% paraffin, is called slack wax. Initially, slack wax is heated and refined, and then converted into normal paraffin wax that is available in the market.
Removing paraffin from distilled pressable paraffin to improve lubricating properties and resistance to cold is crucial. Therefore, in paraffin distillation processes, this product is typically pumped to paraffin warehouses. These warehouses allow paraffin to settle in tanks at the lowest room temperature. Then, through a cooling unit bank, the paraffin is pumped to hydraulic press machines. This process causes the paraffin to exit the distillation phase and solidify.
Subsequent steps of paraffin distillation:
Further steps of paraffin distillation are derived from the “raw” cut with a higher boiling point, and are defined as fractions with high viscosity. This results in further distillation of the unrefined paraffin. Moreover, this fraction itself contains paraffin. However, due to its crystalline nature, this paraffin is not well-suited for separation and filter pressing. Part of the high-viscosity distilled paraffin is cold-settled and centrifuged. This produces an oily paraffin fraction that is defined as petroleum and oil derivatives.
Crude oil is refined from petroleum reserves or microcrystalline waxes in crude oil. The refining process occurs through recrystallization and the settling of paraffin from the naphtha solution at reduced temperatures. This type of paraffin is sometimes called “petroleum paraffin.” At least 85% of the hydrocarbons in this product are of this type.
Paraffin Solid Production Process Analysis:
(DSC) is defined as the derived or differential calorimetry method. (Calorimetry is, in fact, the measurement of calories in this category of petroleum products). This method is used to detect physical or chemical changes in a substance that accompany the absorption or release of heat. If the initial mass of the sample is specified, DSC can measure the thermal event quantities. Analysis by DSC is done with a sample of 0.1 milligrams. Therefore, 5 to 15 milligrams can be considered a standard amount.
Today, one of the most important analytical techniques available is (FTIR), known as infrared spectroscopy or Fourier transform spectroscopy. The main advantage of this analysis method is that it can study any sample in any form, for example: gases, liquids, solutions, powders, films, and surfaces can be examined by selecting the best sampling technique. Another analytical method is GC, which is known as gas chromatography.
Slack Wax Production Method:
Slack wax is a mixture of paraffin wax and oil extracted from crude oil. The range of petroleum derivatives in slack wax is from 5% to 30%. Slack wax is also known as a raw material for fully refined and semi-refined paraffin wax. This product is used to produce all grades of paraffin wax through de-oiling and bleaching processes. The oil removal process or reduction of oil in slack wax occurs in various ways, and the bleaching process is the color change of slack wax from yellow or brown to white. With this type of refining, we can produce paraffin wax from slack wax.
This type of slack wax is the best option for producing different grades of paraffin wax. The production of slack wax is very cost-effective, and due to its petroleum content, it can be the best option for producing various paraffin types. However, the price of this type of paraffin is higher than other paraffins. This product has both light and heavy grades. The difference between light and heavy grades is their melting points.
Waste Paraffin Production Method:
After the paraffin wax production process from slack wax is completed, waste paraffin is produced. The main use of this type of paraffin is in the match industry because its oil content is about 50%, and it has a strong odor and a completely brown color. Waste wax is a fully by-product obtained from de-oiling or sweating paraffin in the paraffin wax production process. Waste paraffin is actually the remaining combination of petroleum and slack wax. This paraffin, officially known as foots oil, is a product obtained from the production of semi-refined paraffin wax. 60% of this type of paraffin is almost produced from 100% slack wax from refineries.
Waste paraffin is brown in color. It is used in the manufacture of matches, lubricants, explosives, fireworks, and so on. Waste paraffin can also be used as a hydrophobic saturating agent, fuel brick, raw material for producing grease lubricants, insulating oils, lubricants, tire and rubber industries, shoe soles, textiles, as well as for producing petroleum jelly and white oil. It is also widely used in plastic production industries.
Liquid Paraffin Production Method:
Liquid paraffin is a transparent substance composed of saturated hydrocarbons with an orderly structure. This type of paraffin is either extracted from kerosene or obtained through the “Fischer-Tropsch” process at gas-to-liquid production sites.
Liquid paraffin is the main raw material for producing laboratory materials. Liquid paraffin is extracted from kerosene, which typically contains 20-25% paraffin and is therefore generally produced near refineries. The kerosene from which paraffin is extracted must be returned to the refinery. More than 80% of liquid paraffin is used for laboratory products. The remaining liquid paraffin may be used for specific solvents. This type of paraffin has various industrial applications, including the production of synthetic resins, paints and lacquers, grease removers, and printing inks. Regular paraffin is used as a solvent in industry for producing polymers and resins, paints, and polishing grease.
Iso-paraffin Production and Application Method:
Paraffins can be categorized into straight chains (regular paraffin) or branched chains (iso-paraffin). Most paraffin compounds are used in natural crude oils and as liquid paraffin. However, iso-paraffins are often produced in refinery processes. When liquid paraffins are used as motor fuel, they cannot produce good engine power. In contrast, iso-paraffins have good characteristics for engine drive and combustion. Paraffin with longer chains, i.e., iso-paraffins, are key components of paraffin. Liquid paraffin is produced from kerosene or diesel through molecular sieve extraction.
After appropriate refining, desulfurization, aromatization, and n-paraffin flow, the cracking unit passes the cut to achieve the desired carbon fractions. Liquid paraffin is used as a solvent. Iso-paraffins are essential in the production of surfactants. Iso-paraffin is used in the manufacturing of metalworking compounds, lubricant oil components, plasticizers, chloroparaffins, as well as in the production of oil for cold rolling aluminum. Iso-paraffin is a catalyst carrier for olefin polymerization. The raw materials of iso-paraffins encompass a wide range of applications.