Bitumen extraction in oil sands-ore water slurry systems was studied using lipids and lipid derivatives as surfactants to promote the efficiency of bitumen recovery. In this study canola oil, tall oil fatty acids (TOFA) which are by-products of pulp mills using the bleached Kraft process, canola oil fatty acids methyl esters which are known as biodiesel (BD), and canola oil fatty acids monoglycerides were used as surfactant additives. Experimental findings suggest that BD, i.e., fatty acids methyl esters, a blend of fatty acids methyl esters, and fatty acids monoglycerides could also be used as surfactant additives to increase the efficiency of bitumen recovery in thermal in-situ processes such as steam assisted gravity drainage (SAGD) and cyclic steam stimulation (CSS) processes. Our experimental findings showed that the required dosage for the surfactant additives would be about 0.1 % of bitumen by mass. Also, interfacial tensions between bitumen and process water (?B,W) and BD and process water (ϒ B,W) were provided as supportive data for the applicability of the method proposed. This paper presents the initial observations. Experiments at high pressure conditions and the analysis of bitumen recovery and produced water chemistry are currently in progress.
Oil sands deposits in northern Alberta, Canada contain about 142×109 cubic meter cube (m3) or 890×109 barrels of bitumen, which makes it one of the largest oil sands deposits in the world (AERCB, 1984). Four commercial plants are utilizing surface mineable oil sands deposits for bitumen production using oil-sands ore water slurry based extraction processes with total bitumen production capacity exceeding 106 barrels/day. Reduction of the surface and interfacial tensions play an important role in the efficiency of bitumen recovery in ore-water slurry systems (Moschopedis et al., 1977 and 1980; Speight and Moschopedis, 1977; Bowman, 1968; Baptista and Bowman, 1969), which are the basic reasons for the success of the Clark How Water Extraction (CHWE) process (Clark, 1939 and Clark and Pasternack, 1932). In the CHWE process, the solubility of naturally occurred asphaltic acids in bitumen which are partly aromatic, containing oxygen functional groups such as phenolic, carboxylic and sulphonic types are increased by the use of caustic NaOH, which act as surfactants reducing the surface and interfacial tensions. This process produces tailings with poor settling characteristics which result in the use of gypsum (CaSO4) as additive to alter its settling and consolidation properties. It is realized that the release water chemistry is harmed by the use of chemical additives in both extraction and tailings disposal processes (Allan, 2008 and 2008; Franklin et al. 2002). Novel extraction process aids, i.e. surfactant additives, have to replace the conventionally used additives, by which extraction efficiency would be improved without harming the fuel quality of bitumen, release water chemistry and geotechnical properties of the tailings. Our research was focused on the use of surfactants from external sources to eliminate the harmful effects of the additives used in the existing oil sands plants.
