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Supercritical fluid extraction and fractionation was used to prepare narrow-cuts from a variety of petroleum vacuum residua. The narrow-cuts were subjected to comprehensive characterization and solubility class separation into saturates, aromatics, resins and asphaltenes fractions. Unlike the bulk property measurements, the narrow-cut characterization data show uneven distribution of key contaminants (with the concentration increasing) as the fraction becomes heavier. Narrow-cut data were used to develop a generalized feedstock characteristic index, KR, that correlates well with the feedstock hydrocarbon constituents and can be used to assess feedstock reactivity and process capability. Downstream refiners can use the narrow-cut data and KR index for process optimization by either cutting deep into the bottom of residua to increase yield or selecting appropriate process units for various residue fractions. Narrow-cut data were also used to develop critical properties of residue fractions, which can be used as input parameters for simulation studies in designing process units for heavy crude and residua.

The Canadian oil sands deposits in northern Alberta contain about 1.3 trillion barrels of crude oil equivalent. The largest of the four major formations is found in the Athabasca region where bitumen is heterogeneously distributed throughout an unconsolidated mineral matrix. About one-tenth of the oil sands in this deposit is economically recoverable by conventional surface mining techniques. The Hot Water Extraction Process (HWEP) is used commercially to recover bitumen from surface mined oil sands ore. The viability of this process relies on the existence of a thin water film around each solid particle in the ore matrix. However, a completely water-wet mineral condition is not generally the case for oil reservoirs, including oil sands deposits. In the latter case, it has been shown that certain solid fractions are associated with significant amounts of toluene insoluble organic matter (TIOM), physically or chemically adsorbed onto particle surfaces. These fractions are generically described as ‘organic rich solids’ (ORS). In bitumen separation processes, the organic matter associated with various ORS fractions represents an impediment to optimum bitumen separation and upgrading. In this sense, these solids are considered to be ‘active’ relative to the ‘inactive’ water wetted quartz particles comprising the bulk of the oil sands ore. Preliminary results indicate that the ORS content of an ore appears to be a better predictor for ore processability than the traditional use of bitumen or fines (−44 μm) contents. Two types of ORS have received particular attention. The first is a coarser fraction, usually less than 44 μm but also occurring as particles greater than 100 μm in diameter. This material typically occurs as aggregates of smaller particles bound together by humic matter and precipitated minerals. During the bitumen separation process, these heavy aggregates carry any associated bitumen into the aqueous tailings, thus reducing overall bitumen recovery. The second important fraction comprises very thin, ultra-fine clay particles with a major dimension of