ABSTRACT
In the United States, asphalt refers to the binder, also known as bitumen. Asphalt can refer to a mixture of bitumen and aggregates, which is usually called asphalt mix in the United States. Asphalt emulsions are used in many applications as they allow the introduction of asphalt at ambient temperature, without the need for high temperature, because of the low viscosity. Emulsions are produced by dispersing asphalt binder as droplets of small diameter with the help of an emulsifying agent. Emulsions are produced in a colloid mill, containing a high-speed rotor, through which hot asphalt binder and emulsifier solutions are passed at specific temperatures. The shearing action of the rotor forms asphalt binder droplets, which get coated with emulsifier and as a result get charged, which prevents them from coalescing. Emulsions are also made with polymer-modified binders, generally requiring higher temperature for manufacturing.
