From tar sands to synthetic crude: Applications of microscopy
The production of synthetic crude oil from tar sands is a complex process involving initial separation of the bitumen from the sand via the hot water process, separation of the bitumen from the water and finally coking of the residual bitumen to maximize the yield of crude oil. Many of the processing concerns center around decreasing the amount of water and clay which is carried with the bitumen product and decreasing the amount of bitumen which is carried with the water, sand and clay tailings. The crude oil yield in the final coking step is then dependent upon the efficiency of these preliminary steps as well as the coking conditions.Both electron and optical microscopy have important applications in understanding these systems. Direct observation of frozen hydrated samples in the electron microscope has been utilized for evaluation of both the size distribution of the dispersed phase and the chemical composition.