Bitumen emulsion is a dark brown water-bitumen mix. It is produced by bitumen dispersion in water with various emulsifiers.
Anionic bitumen emulsions interact with various minerals in different ways. This defines its area of application. Road construction tasks are much better solved by cationic bitumen emulsions.
Application of bitumen emulsions has a range of advantages compared to hot mix:
- reduction of bitumen consumption;
- no need for heating (reduction of labour and power costs);
- no toxicity (no pollution of environment);
- no fire-hazard;
- efficiency of application (can be applied on wet surfaces).
Bitumen emulsion production plants make emulsions of three types: fast-, middle- and slow-breaking emulsions.
The invention of cationic bitumen emulsions opened up a range of new possibilities in the area of “cold” technologies, possessing some undeniable advantages in comparison with bitumen, which requires heating. Those are:
- low viscosity of emulsion. This material can be spread over and mixed with mineral substances at ambient temperature. There is no need to heat the emulsion. Besides the reduction of power costs, emissions to the atmosphere are also reduced. There is no way for personnel to get burned, so labour safety is improved;
- the job does not depend of weather conditions. The ability to interact with wet materials makes it possible to repair roads even at +5ºС;
- flexibility of job planning. Emulsion-mineral mixes can be stored for up to 6 months without breaking;
- better adhesion of binder and base due to application of an emulsifier. Road top made of bitumen emulsion is noted for high durability, resistance to cracking and rutting;
- applicability of mineral materials with natural moisture content to make gravel-emulsion mixes.
The table shows areas of application of bitumen emulsions depending on breakdown rate.
Table 1. Area of application of bitumen emulsions depending on breakdown rate
Type of emulsion
Area of application
|Road surface treatment, protective wearing course and tack coating|
|Dust laying, arrangement of wearing course, “Slurry seal”, preparation of black crushed-stone and vesicular gravel mixes, road surface treatment, tack coating|
|Preparation of bitumen-mineral mixes, topping of road by means of penetration method|
Currently the sphere of application of bitumen emulsions is quite wide. This construction material enables to expand the road construction technology in the following directions:
- preparation of cold asphalt-concrete mixes;
- production of impregnated macadam surfacing for construction of road bottom layer and road surface dressings;
- laying of protective coatings for old road surface treatment;
- gravel compaction of surface course;
- sand sealing for treatment of road surface with many cracks;
- “Slurry seal” type cover for application of thin layers of cold asphalt-concrete surfacing.
Among other processes we’d like to note:
- ground stabilization;
- dust consolidation on dirt roads;
- recycling of asphalt-concrete;
- black-topping of garden road lanes;
- curing of newly-laid cement concrete mixes.
For production of bitumen emulsions, GlobeCore manufactures UVB-1 plants designed for 1 to 8 m3/hour capacity range.
This product has the following advantages:
- capability to produce high-grade bitumen emulsion irrespectively of raw material quality due to the addition of plasticizers, adhesion additives and flux oils;
- production of all type of emulsions, such as CRS, CMS and CSS-1,2, as well as anionic emulsions of corresponding types, including sub-type h;
- dilution of blending concentrate with water is performed directly in the plant;
- safety (automatic emergency stop);
- emulsion produced complies with the ASTM D 2397-98 and D977-98 standards;
- small footprint;
- simple maintenance and operation.