For reliable and quick penetration during application, bitumen emulsions are simply diluted bitumen. It is extensively used for different applications in construction industries. Surface treatment is done to ensure that the outer layer of the path or pavement is kept safe from water or moisture penetration. It resists skids and safeguards the highways. The performance is however influenced by aggregate factors, emulsion consistency, and temperature.

How is Bitumen Emulsion made?
Bitumen emulsion is developed in two simple steps. The water is first combined with an emulsifying agent and other chemical agents. Then, a colloidal mill is used to combine water, emulsifier, and bitumen. Depending on the end-use of bitumen emulsion, the quantity of bitumen is added to the mixture. When the emulsifier is being made as a key product, it can be used between 60-70%.

The typical amount of bitumen added to the mixture is between 40% and 70%. The colloidal mill separates the bitumen into microscopic particles. The average droplet size is approximately 2 microns. But the droplets try to settle down and join with each other. The emulsifier, thus added, produces a coating of the surface charge around every droplet of bitumen which, on the other hand, helps keep the droplets to away from each other. The blend obtained from the colloidal mill is processed and used according to guidelines and later stored in storage tanks.

Types of Bitumen:
The bitumen emulsion is categorized into two types:
Based on setting time
Based on surface charge

Based on Setting Time
If emulsions of bitumen are added to aggregates, water is evaporated, and the solvent is removed. Then bitumen flows over the aggregate base, serves as a binding agent and slowly reinforces itself. This process is divided into the following three groups, depending on the speed at which water evaporates and bitumen particles disperse from water:
Rapid Setting Emulsion (RS)
Medium Setting Emulsion (MS)
Slow Setting Emulsion (SS)

Bitumen is meant to break easily as the emulsion is a rapidly setting type of emulsion. This form of emulsion sets easily and cures. Once placed on aggregates, the emulsions of the medium setting do not crack unexpectedly. However, when the mineral's coarse shards are combined with the aggregate emulsifier mixture, the breaking process begins. Slow setting emulsions are created with the assistance of a special type of emulsifier which slows down the setting process. These emulsion forms are quite robust.

Based on Surface Charge
Bitumen emulsions are divided primarily into the following three groups depending on the type of surface charge:
Anionic Bitumen Emulsion
Cationic Bitumen Emulsion
Non-Ionic Bitumen Emulsion

Bitumen particles are electro-negatively charged in case of anionic bitumen emulsion, whereas in the case of cationic emulsions, bituminous particles are electro-positive. Today, a cationic emulsion of bitumen is used most often. Based on the mineral composition of the aggregate used for building, it is important to pick an emulsion of bitumen. The composition of the aggregates becomes electro-negatively charged in cases of silica-rich aggregates. A cationic emulsion should, therefore, be added. This helps to spread bitumen and combine it with aggregates more effectively. For aqueous solutions, non-ionic surfactants do not attract ions. The solubility is based on the existence of polar molecules. The use of nonionic surfactants as an emulsifier, although not just in the water process, but in the bitumen phase, as above described, is of great interest as they are consistent with all ion surfactants.

No emulsion of any kind is sufficient for each function; it depends on acidic or basic nature of the aggregate. Based on air temperature, wind speed and emulsion size, the setting time may differ. The capacity for storage is minimal. The above classification is a guide to choose the right match for your requirements.