Water-bitumen emulsion is highly appreciated by building and road construction companies. This is due to its ease and safety of use in comparison with mixtures based on solvents and petroleum products such as kerosene. As a rule, water-bitumen emulsion is obtained by blending liquid bitumen with water, special emulsifiers and acids – a process that relies on a precisely engineered bitumen mill to achieve consistent quality.
Having years of experience in designing and building blending machines and bitumen emulsion units, GlobeCore is one of the most reliable manufacturers of modern equipment for production of water-bitumen emulsions anywhere in the world today.
The Colloid Mill: Heart of Bitumen Emulsion Equipment
A colloid mill is considered the heart of any bitumen mill setup, where bitumen is ground into small droplets and then evenly distributed in water. In the past, manufacturers used blending equipment such as dispergators and ultrasonic homogenizers to perform the wet grinding of the dispersed phase of bitumen production.
GlobeCore colloid mills for wet grinding can produce highly stable dispersed systems from two or more mutually insoluble substances. Bitumen emulsion units, depending on the desired size of bitumen droplets, use three groups of colloid mills.
Three Groups of Bitumen Mill Colloid Systems
Group 1 – provides 90% of droplets with a size of less than 5 microns (minimum droplet size of 1-2 microns). This type of bitumen mill is used to manufacture polymer-modified emulsions, bitumen emulsions for surface treatment (“chip seal”), recycling, soil stabilization, grouting, tack coating and similar technological processes.
Group 2 – provides 90% of droplets at the outlet with a size of less than 10 microns (minimum droplet size of 4-5 microns). Areas of application include simple slurry mixtures, surface treatment, tack coating, recycling, and grouting.
Group 3 – produces bitumen emulsions with a minimal droplet size of more than 5 microns (no more than 10% of droplets larger than 10 microns). Such bitumen emulsions are used for surface treatment, tack coating and grouting.
How a Bitumen Mill Processes Raw Materials
Since colloid mills are mostly mounted in line with continuous blending units, components are supplied directly to the unit. As a rule, the water phase is prepared in advance to reach the required temperature, pH level and emulsifier metering. Then the water phase and warmed-up bitumen are supplied to the input of the bitumen mill to be dispersed. If necessary, the viscosity of the bitumen is reduced by injecting flux into the feed line.
The ratio of components is maintained automatically by metering pumps in accordance with the program, or by temperature control of the source components — measuring the temperature of the bitumen emulsion at the outlet (as a rule, 85-94°C) and adjusting the flow accordingly.
Modified Emulsions and Flexible Output Control
If required, depending on the formula, the bitumen mill may be supplied with latex, allowing for modified bitumen emulsion production. At the outlet of the colloid mill, there is a three-way valve that provides for recycling of the water solution of emulsifier, mill flushing, or discharge of the finished bitumen emulsion product.
Key Benefits of GlobeCore Bitumen Mill Equipment
GlobeCore’s continuous bitumen mill equipment offers a wide range of benefits, including:
- Rapid change of the type of emulsion produced
- No impact of reagents on staff
- Low operating costs