23 November 2005
A new report identifies the knowledge gaps on the road to a wide-scale utilization of synthetic crudes, and the directions of research that is necessary to ensure rational investment in oil sands energy resources in Alberta, Canada. The report—jointly published by Natural Resources Canada, National Research Council Canada, and the US Department of Energy—is based on the outcome of the Oil Sands Chemistry & Engine Emissions Roadmap Workshop, which was held in June in Edmonton, AB.
The oil sands carry about 10% (wt.) of bitumen, a tar-like substance composed largely of heavy aromatic hydrocarbons. Bitumen is recovered by either in-situ methods or by processing oil sands produced in a mining operation. Bitumen is then further processed to obtain synthetic crude. Synthetic crude from Alberta oil sands is currently used by a number of refineries, mostly in the US Midwest and West Coast. However, due to a number of different properties, synthetic crude can be blended with conventional crude oil only up to 10-15%. Additional processing capabilities—by synthetic crude producers and/or the receiving refineries—will be necessary to ensure the quality of fuels made from feedstocks with higher proportion of synthetic crude.
The report identified a number of areas where more research is needed:
- Existing engines: The greatest challenge in the application of synthetic crude based fuels is presented by diesel fuels and jet fuels (as opposed to gasolines). The higher aromatics content in synthetic crude results in high aromatics and low cetane diesel, which produces higher emissions. Car makers who plan to introduce light-duty diesel engines in the North American market have been calling for increased cetane specification in US fuels (the minimum cetane number in Europe is 51, compared to 40 in the USA).
- New engine/combustion technologies: Low temperature combustion (LTC) and partial homogenous charge compression ignition (HCCI) are being commercialized as in-cylinder NOx reduction technologies. Contrary to the conventional diesel combustion, low cetane number has been preferred in HCCI combustion, according to several studies. Chemical characterization and modeling of different fuel types in new internal combustion engines will be necessary to fill existing technology gaps.
- Emission control systems: In existing engines, there is a lack of understanding of how oil sand derived fuels impact the performance of emission control devices, such as soot filters, NOx and EGR system performance.
- Future fuels: Other alternatives will be increasingly used—such as biofuels or Fischer-Tropsch fuels—as a diesel fuel component, both for existing diesel engines and future new engines.
Alberta is currently producing about 1 million barrels per day of oil sands derived crude. This number is projected to double in 10 years, and to reach 5 million barrels daily by 2030, according to the report. Canada is second in proven reserve size to Saudi Arabia, with established reserves of 175 billion barrels of oil sand-derived crude recoverable by known technology today, and much larger additional potential with improved technology. Similar reserves are also being developed in Venezuela.
Download the full report