Asphalt-based coatings manufacturing

The first step in the manufacture of asphalt-based coatings consists of the distillation of crude petroleum, which results in distillate fractions (gasoline, naptha, kerosene, diesel fuel, and gas oil). The fraction of crude oil that boils above approximately 300 C is not distilled, but is withdrawn from the bottom of the distillation... 

Asphalt emulsions are dispersions of asphalt in water that are stabilized into micelles with either an anionic or cationic surfactant. To manufacture an emulsion, hot asphalt is mixed with water and surfactant in a colloid mill that produces very small particles of asphalt on the order of 3 pm. These small particles of asphalt are prevented from agglomerating into larger particles by a coating of water that is held in place by the surfactant. If the asphalt particles agglomerate, they could setde out of the emulsion. The decision on whether a cationic or anionic surfactant is used depends on the application. Cationic stabilized emulsions are broken, ie, have the asphalt settle out, by contact with metal or silicate materials as well as by evaporation of the water. Since most rocks are silicate-based materials, cationic emulsions are commonly used for subbase stabilization and other similar applications. In contrast, anionic emulsions only set or break by water evaporation thus an anionic emulsion would be used to make a cold patch compound. 

Manufacturing steps and coproducts in producing asphalt coating base. 

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