Particle Analysis of Road Materials

Asphalt emulsions are droplets of asphalt dispersed in water with the aid of an emulsifying agent. Particle size of the asphalt droplets is critical to stability and application performance. Asphalt emulsions are manufactured by a high-speed, high shear mechanical device (usually a colloid mill) that divides the asphalt into tiny droplets and disperses it in the water. Typical products have a size range from sub-micron up to ten microns, with an average particle size in the one to five micron range. Variation in settings, raw materials, and requirements of the final product will vary both the average size and distribution width.

HORIBA laser diffraction particle size analyzers are a proven technology for measuring asphalt emulsions. Systems from the full-featured LA-960 Particle Size Analyzer to the portable LA-350 have been successfully used for these measurements.