Lubricating grease production process flow roughly production process

1.Solvent dewaxing In order to maintain good fluidity of lubricating oil under low temperature conditions, the wax that is easy to solidify must be removed. This process is called dewaxing. The dewaxing process can not only lower the freezing point of lubricating oil but also obtain wax. The so-called waxes are those hydrocarbon compounds that become solid at room temperature of 15°C. The main bodies are n-alkanes and cyclic hydrocarbons with long side chains. N-alkanes above C16 are solid at room temperature. There are many dewaxing methods currently commonly used: cold press dewaxing, solvent dewaxing and urea dewaxing. Propane deasphalting is a method that uses propane to extract hydrocarbons from residual oil. It uses liquid propane's small solubility to asphalt near the critical temperature and high solubility to oil alkanes, naphthenes, and less aromatic hydrocarbons to make the oil separate from the asphalt. The critical temperature of propane is 96.81°C and the critical pressure is 4.2MPa.The so-called critical temperature means that when the liquid is heated above this temperature, no matter how much the external pressure increases, it can no longer prevent the liquid from boiling and transforming into steam. The external pressure corresponding to the critical temperature is called the critical pressure. In the area below the critical temperature of propane and close to the critical temperature, the solubility of liquid propane to oil and asphalt decreases with increasing temperature. But the solubility for bitumen decreases very quickly and the solubility for oil decreases very slowly. So the solubility of oil in propane is much greater than the solubility of asphalt at a certain temperature in this temperature range. The deasphalted oil obtained by propane treatment needs to be refined and dewaxed like other distillates.

2.The quality of the oil after solvent refining and dewaxing after clay refining has basically met the requirements, but it generally contains a small amount of unseparated solvent, water, and certain macromolecular condensates, colloids and impurities produced by heating when recovering the solvent. Stabilizing compounds may also bring out mechanical impurities such as iron filings from processing equipment. In order to remove these impurities and further improve the color of the lubricating oil, improve its stability and reduce carbon residue, additional refining is required. A commonly used supplementary refining method is clay treatment. White clay refining uses the adsorption capacity of activated clay to adsorb various impurities on the activated clay and then filters out the clay to remove all impurities. The method is to add a small amount of pre-dried activated clay, usually a few percent, to the oil while stirring and heating so that the oil and clay are fully mixed and the impurities are completely adsorbed on the clay, and then filtered with fine filter paper to remove the clay and mechanical impurities. Refined base oil is available.

3. Hydrogenation and refining. Hydrogenation and refining: The color, stability and odor of the oil after hydrogenation and refining are improved, and the susceptibility to antioxidants is significantly increased, while the viscosity and viscosity-temperature properties change little. The content of non-hydrocarbon elements such as sulfur, nitrogen, and oxygen decreases. The color and stability of oil mainly depend on the small amount of condensed ring compounds and high molecular unsaturated compounds contained in the oil. During hydrogenation, some of the aromatic rings in such compounds become cycloalkanes or ring-opened unsaturated compounds become saturated compounds. This can make the color of the oil lighter and improve its stability. Lubricating oils containing non-hydrocarbon elements such as sulfur, nitrogen, and oxygen will generate corrosive acids during use. When hydrogenated, these elements will react with hydrogen to form hydrogen sulfide, amines, water and other gases that are separated from the oil, thus improving product quality. The product yield of hydrogenation supplementary refining is higher than that of clay refining. There are no problems such as clay supply and waste clay treatment. It is a better method to replace clay refining.

4. Hydrotreating or hydrocracking: The hydrotreating process can not only improve the color, stability and odor of the oil, but also improve the viscosity and temperature properties. It can replace clay refining and solvent refining, killing two birds with one stone. It uses a variety of hydrocracking reactions in addition to the various reactions of hydrogenation and supplementary refining under harsher conditions than hydrogenation and supplementary refining, so that most or all of the non-ideal components are hydrogenated into cycloalkanes or alkanes and converted into ideal components. For example, polycyclic hydrocarbons are hydrogenated and ring-opened to form hydrocarbons with few rings and long side chains. Therefore, the oil produced by hydrogenation has better viscosity-temperature properties.

5. Hydrogenation and condensation reduction: The operating conditions of the hydrogenation and condensation reduction process are more stringent than those of hydrogenation. The lubricating oil raw material undergoes hydroisomerization and hydrocracking reactions under the action of the catalyst. The hydrogenation process not only has a refining effect, but also has the effect of isomerizing wax, thereby converting n-alkanes with higher freezing points into condensed oil. Iso-alkanes or low-molecular-weight alkanes with lower points achieve the purpose of lowering the freezing point. Lubricating oil product blending is the last important step in the lubricating oil preparation process. According to the formula of the oil, add the lubricating oil base oil components and additives in proportion and order to the blending container, stir with mechanical or compressed air, and pump for circulation. , pipeline static mixing and other methods to mix evenly and then sample and analyze according to product standards, it will be an official product.