HEAVY OIL OXYGENATE BLENDS AND VISCOSITY MODELS

The transportation of bitumens and heavy oils is made difficult by the excessively high viscosity of these compounds. The current solution t o this problem is the dilution of the compounds with C4+ liquid hydroc arbon to the extent that the mixture becomes pumpable through surface pipelines. To open new avenues for transportation of heavy oils, oxyge nates, which are gaining acceptance as octane enhancing components in gasoline, are investigated as an alternative diluent. This study inves tigates the use of the oxygenate tert-amyl methyl ether (TAME) as a bl ending diluent with Cold Lake bitumen, and compares the results to a p revious study by the same authors which utilized methyl tert-butyl eth er (MTBE) as the blending agent. A liquid viscosity model was utilized to calculate the component viscosities as a function of temperature, and then a mixing rule to determine blend viscosities as a function of composition. The mathematical viscosity model suggested for the blend s in these investigations was found to be accurate over the entire ran ge of compositions and temperatures for both oxygenates. A number of s imple experimental distillations performed on mixtures of bitumen and oxygenates proved that these easily separate without any significant l oss.