S.Hassan Firoozifar - Bitument & Asphslt Department , Asphalt nemoonej Group
Sanaz Forutan
Sara Forutan
Mahdieh G.Abadi

Breaking of an emulsion is an irreversible process that can occur as a result of evaporation of the water phase, or the absorption of the water phase into porous aggregate. Then the bitumen droplets adhere to the aggregate surface that has been modified by the surfactant and combine with each other, forming the bitumen film. Depend on the rate of this process, there are three kinds of bitumen emulsions: Rapid setting, Medium setting, Slow setting. In order to control the breaking rate of bitumen emulsions on the surface of evaluated. The influence of each factor consists of pH, concentration of emulsifier, temperature, particle size and content of bitumen was studied by changing each of parameters in a wide range. In all cases, changing the related parameter had limitation and excess amount caused a reverse effect on the breaking rate. Therefore, all these parameters were optimized to achieve the best result.

Breaking rate , Bitumen emulsion , Aggregate , Coagulation , Emulsifier