Iran Bitumen Emulsion , usually having a relatively low average particle size, can be continuously and speedily prepared by a process comprising feeding emulsion components into the first of at least two static mixers, arranged in series.

The product is passed from the first mixer to the second mixer maintained at a temperature lower than that prevailing in the first mixer and below the boiling point of water.

The final emulsion product is obtained from the outlet of the second mixer.Bitumen emulsions of up to 70 wt. bitumen of mean particle size of from 2 to 8 microns are also described.