Heavy crude oil viscosity reduction for pipeline transportation

The approaches used for reducing the viscosity of a heavy crude include heating, blending with a light crude and with kerosene, and forming oil-in-water emulsions. Heating had a dramatic effect on the heavy crude viscosity, but it failed to achieve a practical level; consequently, blending the heavy crude with either light crude or kerosene was attempted and further reduction was achieved, but substantial amounts of these expensive diluents are required. Alternatively, emulsion formation was carried out, and it was established that a practical level of reduction is achievable at 70-75% oil content, in the high shear rate range, and at 30-50°C. The effect of temperature on the viscosity of the crude oil mixtures and emulsions can be fitted on the American Society for Testing and Materials (ASTM) double-log model with an average deviation of 7.2-9.4%.