In the road construction industry, bitumen serves as a binding material. At ambient temperatures howver, it is very viscous and cannot be used as intended without heating.
In today’s modern road construction industry, there are three ways to make bitumen suitable for road construction projects:
- To warm up bitumen to between 100º and 200°C;
- To blend it with solvents (asphalt paint); or
- To make bitumen emulsion.
Bitumen emulsion is a material where small particles of bitumen are distributed in a water phase (bitumen in water dispersion). Such emulsions may be made of bitumen of different viscosity depending on the required performance characteristics of the final product. According to the chemical nature of the surface-active substances, bitumen emulsions are divided into groups such as:
There are three classes of bitumen emulsions depending on the blending stability:
- Medium-breaking; and
It should be borne in mind that cationic and anionic emulsions should not be blended together since their charges are equalized and emulsion separates into bitumen and water. The bitumen emulsion storage tanks should be cleaned thoroughly before filling them with a different kind of bitumen emulsion.
The physicochemical performance characteristics of bitumen emulsion and dispersion degree are determined by the properties and amount of bitumen, emulsifier, and acid.
Specialists consider that it is the emulsifier that determines the quality of bitumen emulsion. There are a lot of chemical compounds that can be used to emulsify bitumen. But, only some substances have found practical use because of rigid technical and economic regulations.
In recent times, cationic bitumen emulsions have become preferable since they are more unique and make binding material adhesive when reacting with the acid materials and other natural elements. As compared to hot bitumen, bitumen emulsions have a wide spectrum of benefits that include:
- Significant bitumen savings (up to 30-50%);
- Energy conservation (up to 25-40%) since there is no need to warm up bitumen emulsion before application;
- Compatibility with wet solid material;
- Good adhesion of bitumen to roadbed;
- Fire safety; and
Bitumen emulsion production is realized by the use of a colloid mill. The quality of the final product depends on the following parameters of the colloid mill:
- Air-gap distance between the rotor and the stator (may be adjustable or constant);
- Rotor speed. This parameter depends on dimensions and power of the mill; and
- Design of the mill.
has designed its UBV-1 units to produce bitumen emulsions. Their capacity may vary from several hundreds of kilograms (laboratory units) to several tens of tons per hour (plant models).
bitumen emulsion units allow for production of high-quality bitumen emulsions.
The GlobeCore UVB-1 bitumen emulsion units
have gained widespread acceptance in many parts of the world. Bitumen emulsions, produced by GlobeCore equipment, can be applied to carry out a wide spectrum of road construction projects such as:
- Tack coating;
- Ground stabilization;
- Crush-stone grouting;
- Sludge compaction;
- Dust laying;
- Minor road works;
- Cold recycling;
- Pothole repair;
- Production of cold bitumen-concrete mixtures, paving type Slurry; and
- Coarse surface treatment, paving type Chip Seal.