1. Increase the fineness of emulsified asphalt particles and improve the distribution state of asphalt particles. The size and distribution of asphalt particles in emulsified asphalt have a great influence on the stability of emulsified asphalt. The smaller the particle size of asphalt particles, the narrower the particle size distribution range, and the better the stability of emulsified asphalt. The standard stipulated by ASTM in the United States is: particles smaller than 1um account for 28%, particles of 1-5um account for 57%, and particles of 5-10um account for 15%.

When asphalt particles settle under the action of gravity, the rate of particle sedimentation is related to the size of asphalt particles, the relative density of asphalt, the relative density of water, and the viscosity of water. Among them, the radius of asphalt particles and the sedimentation rate are in a square relationship. In other words, the particle size of asphalt particles has a great influence on whether emulsified asphalt can be stored stably.
2. Reduce the density difference between asphalt and water phase. The relative density of asphalt is different, and the sedimentation form of emulsified asphalt produced is also different. Generally, emulsified asphalt particles settle in the direction of gravity; when the density of the water phase is less than the density of asphalt, the asphalt particles will "settle" upward. In actual production, some metal chlorides are added to the water phase to improve the stability of emulsified asphalt. One of its mechanisms is to reduce the density difference between asphalt and water.