Rheological behavior of concentrated bitumen in water emulsions

The effect of bitumen concentration and mean drop diameter and distribution on the rheological behavior of bitumen in water emulsions was investigated . Results obtained showed that the emulsion viscosity is severely affected by the type of drop size distribution. In fact, emulsions with a bimodal dr op diameter distribution exhibit viscosity values which were at least 1 ord er of magnitude lower than the viscosity of similar emulsions, having the s ame bitumen concentration and an equivalent mean drop diameter, but with a unimodal distribution. It was also found that concentrated bimodal emulsion s behave like Newtonian fluids, while the unimodal counterparts are non-New tonian and show some pseudoplasticity. Because of their very simple rheolog ical behavior, bitumen in water bimodal emulsions are of great importance i n the processes of transporting, handling, and commercializing extremely vi scous hydrocarbons.