Bitumen emulsion is a mixture of water & bitumen which has being developed and exponentially increased sinned they were created in 1900. A dispersion of bitumen particles on water, stabilized with the addiction of surfactants – Surface active agents – or most commonly known as emulsifiers, that will permit the bitumen to de diluted in water.

Bitumen emulsions are by far the most commonly used binder in cold paving technologies, allowing numerous applications such as tack coats, microsurfacing, fog seal and chip seals. ‘cold technologies’ are generally regarded as environmentally friendly construction technologies (EFCT) because they help reduce energy spending thanks to lower operating temperatures and the use of wet aggregates, and they diminish fume and particle emissions to the atmosphere and therefore limit the impact on the environment. Base on that we know bitumen emulsion as a green bitumen which is more efficiency, ease of use and more safe as well. All of these advantage cause that using this bitumen grow up day by day.

Bitumen emulsions can be divided into three classes, based on surface charge:

•     Cationic bitumen emulsions
•     Anionic bitumen emulsions
•     Nonionic bitumen emulsions

Also bitumen emulsions are classified base on setting time. When bitumen emulsions are applied on aggregates, water starts to evaporate causing separation of bitumen from water. And then bitumen spreads on the surface of the aggregate and acts as a binding material and slowly attains its strength.

Depending upon the speed at which water evaporates and bitumen particles separate from water, it is classified into following 3 types.

•     Rapid Setting Emulsion (RS)
•     Medium Setting Emulsion (MS)
•     Slow Setting Emulsion (SS)

below you could see BS group different bitumen emulsion grades: