Co-processing heavy oils with Fischer-Tropsch syncrude

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The project proposal deals with co-processing of oilsands bitumen (heavy oil) and synthetic oil produced by Fischer-Tropsch (FT) synthesis. This type of co-processing has not been studied before. It will be shown why this specific combination holds advantages for Canadian industry, as well as why the work may lead to an improvement. Oilsands bitumen contributes 6-7 % of the gross domestic product of Canada. One of the major challenges in getting the bitumen to market is its poor fluidity (high viscosity) - it has the flow properties of toffee. This is due to the lack of light material in the bitumen and the high apparent molecular weight of bitumen. Bitumen fluidity is improved in mainly two ways: the bitumen is diluted with 25-30 % gasoline range material to produce diluted bitumen (Dilbit), or the bitumen is converted at high temperature to reduce the apparent molecular weight and produce Synthetic Crude Oil (SCO). Although Canadian bitumen producers do not currently have Fischer-Tropsch units installed, there are good reasons why this may be considered in future. Some of the advantages are: (a) FT oil is a good source of light gasoline-range material. Presently Canada imports around 17 million liters per day of gasoline-range material just to satisfy the needs for diluted bitumen production. (b) High temperature processes currently used by industry to upgrade bitumen to SCO also produce low value carbon products. These low value carbon products can be gasified to produce feed that can be used to produce FT oil. (c) During the production of FT oil a lot of heat is released. This energy can be used to produce steam, instead of burning natural gas to produce the equivalent amount of heat. The steam can in turn be used in the production of bitumen from oilsands. This proposal deals specifically with co-processing of heavy oil and FT oil. Heavy oil is upgraded on its own by Canadian industry. There are also industries that upgrade FT oil. There are no examples of integrated facilities that co-process heavy oil and FT oil. There are marked differences in reactivity, phase behavior and chemistry of these materials. Understanding and using these differences to benefit both, is a challenge and an opportunity for innovation. The approach that we want to follow is to fundamentally understand the nature and extent of the interactions during co-processing of heavy oil and FT oil. This proposal is limited to an investigation of the co-processing by mild thermal conversion. The plan is to attract industrial funding to expand the study to other conversion processes too. Technical description: During thermal conversion, hydrogen exchange between molecules and the way in which the reacting molecules are stabilized, affect liquid yield. The heavy oil is rich in species that like to exchange hydrogen to produce light gaseous products and solid coke, which reduces the amount of the more valuable liquid product. Some of our recent research (Energy Fuels 2013, 27, 3061-3070) indicated that there may be a benefit to co-process FT oil with heavy oil. FT oil is also resistant to coking (De Klerk, A. “Fischer–Tropsch refining”, Wiley-VCH, 2011). This is the key to develop an improved process by co-processing the heavy oil with FT oil. The research objective is to track hydrogen redistribution during thermal conversion, so that a fundamental understanding of the process chemistry can be developed.