Coal asphalt manufacturer Zhang Yu
1.Distillation method: It is the first atmospheric distillation, separating gasoline, kerosene, diesel and other light fractions, and then separating the vacuum fraction (residual pressure 10 100 mmHg) through vacuum distillation, and the remaining residue can directly produce asphalt products when it meets the specifications of road asphalt, and the resulting asphalt is also called straight-run asphalt, which is the main method of producing road asphalt.
2.Solvent precipitation method: non-polar low-molecular-weight alkane solvents have different solubility of each component in the vacuum residue, and the difference in solubility can be used to achieve component separation, so as to remove the components in the vacuum residue that are unfavorable to the properties of asphalt, and produce asphalt products that meet the requirements of the specification, that is, the solvent precipitation method.
3.Oxidation method: It is to blow vacuum residue or deoiled asphalt into the air, blow into the air within a certain temperature range, so that its composition and properties change, and the resulting product is called oxidized asphalt. The vacuum residue is vaporized and evaporated under the action of high temperature and air blowing, and a series of reactions such as dehydrogenation, oxidation, polymerization and condensation occur at the same time. It is not just an oxidation reaction, but a very complex reaction process by the interaction of multiple components, what we usually call oxidized asphalt is also called oxidized asphalt, also called air blowing method and air blown asphalt.
4.Blending: Asphalt produced by blending method initially refers to the product obtained by readjusting the 4 components made of the same ** according to the proportion required for quality requirements, that is, synthetic asphalt or reconstituted asphalt. With the development of process technology, the first level of mixed ingredients continues to expand. As.
The residue or component of the same or different ** of the first and second processing, as well as various industrial waste oils, can be used as blending components, which can reduce the dependence on oil sources in asphalt production. Due to the increasing lack of suitable bitumen for the production of asphalt, the flexibility and economy of blending it are increasingly valued and widely used.
5.Emulsification method: the surface tension of asphalt and water varies greatly, and it is not miscible at room temperature or high temperature. When the asphalt undergoes high-speed centrifugation, shearing, impact and other mechanical actions, the particle size is 01 5 microns, dispersed into the aqueous medium containing surfactant (emulsifier-stabilizer), because the emulsifier can be targeted to adsorb on the surface of asphalt particles, thereby reducing the interfacial tension of water and asphalt, so that asphalt particles can form a stable dispersion system in water, that is, oil-in-water emulsion. The dispersion system is brown, the asphalt is the dispersed phase, the water is the continuous phase, and the fluidity is good at room temperature. Emulsified asphalt is in a sense the use of water to "dilute" the asphalt, thereby improving the flow of the asphalt.