Types of emulsion bitumen Emulsion bitumens used in road construction can be classified in terms of electric charge and breaking speed and time (separation of bitumen particles from water). Types of emulsion bitumen in terms of electric charge: In terms of electrical charge, emulsion bitumens are divided into categories: – Anionic Bitumen Emulsion, in which the electrical charge of the bitumen particles inside is negative. This type of emulsion bitumen was invented and used since the beginning of the 20th century (1920 AD). Cationic Bitumen Emulsion in which the electric charge of the bitumen particles is positive. This type of emulsion bitumen was created in the mid-1950s following some problems in the use of anionic emulsion bitumens regarding the breaking of the emulsion and the adhesion of the bitumen to materials with a negative electric charge, which meant a major advancement in technology.
Because, unlike anionic emulsion bitumen, in which the breaking process was not done chemically, and the water must be evaporated to cause the breaking process in the emulsion, while in the cationic emulsion bitumen, the breaking process was done chemically, which in addition to timely breaking, proper adhesion It also creates more heat than anionic emulsion bitumens.
This caused the production of cationic emulsion bitumens to reach 50% of the total production in 1962, and in 1971 it accounted for 90% of the total production of emulsion bitumens in the world. – Non-ionic emulsion bitumens Non-ionic emulsion bitumen is mainly used in industry and is not usually used in road construction. Types of emulsion bitumens in terms of breaking speed After the use and implementation of emulsion bitumen, the water in the separate mixture and bitumen gradually coats the surface of the road or around the aggregates, which is called the emulsion breaking process. Emulsion Bitumen Asphalt Bitumen is used as an adhesive in different ways. Pure bitumen is solid or semi-solid at ambient temperature, which does not have the required efficiency, but it can be increased and usable in three ways, which are: – Heating pure bitumen which is used for hot asphalt. – Mixing bitumen with petroleum solvents (dissolved bitumen) which, in addition to the high price of petroleum solvents, also leads to the problem of environmental pollution. – Mixing bitumen with water in the form of emulsion bitumen, which, in addition to having no environmental pollution, is completely liquid at ambient temperature and has a significant efficiency in mixing with stone materials and surface coating and sealing of asphalt surfaces, especially in wet conditions.