Structural and Molecular Characterization of Oil Sands and Heavy Bitumens Derived from Domestic Reserves

Non-conventional oils have become more attractive to meet energy requirement of the world since conventional oils constitute approximately only one-third of the total reserves and almost half of it already produced. Increasing oil consumption triggered by the growing energy demand results in a sharp decrease in conventional oils and opens up new alternatives for non-conventional ones, but they bring up new challenges in upstream, midstream and downstream processing as well. 

Since researches try to overcome these challenges by developing new technologies, detailed characterization of these unconventional resources play an important role for their feasibility and processibility in the state-of-the-art upgrading technologies such as delayed cokers. These analyses are of paramount importance for the design of new processes as well not only for the conversion of heavier hydrocarbons into lighter and more valuable ones in downstream phase but also for the upstream and midstream phases.

In this study, non-conventional oils such as domestic bitumen and oil sands are investigated by means of elemental analysis, molecular weight analysis / Gel Permeation Chromotograpy (GPC), Proton Nuclear Magnetic Resonance (H-NMR), Differential Scanning Calorimetry (DSC), Thermal Gravimetric Analysis (TGA), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), GC-Simulated distillation, American Petroleum Institute (API) gravity and Conradson carbon test. By means of the solvent sequence protocol, subgroups of these heavier feedstocks such as saturates, aromatics, resins and asphaltene content are also measured that is directly related with the compatibility and stability of possible feedstocks to be processed in refining operations.

The results indicate that these non-conventional oils can be used in current upgrading technologies such as delayed coking process but proper blends are to be prepared to meet the feedstock’s processability limitations such as asphaltene and sulfur content. The physical and chemical analysis of these possible feedstocks will also provide crucial information for the prediction of the final properties of downstream products and also for the design of new upstream, midstream and downstream processes.