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Abstract Chemical-assisted waterflooding enhances the ultimate recovery of a conventional waterflooding process through several mechanisms such as reducing interfacial tension between water and oil, formation of in-situ emulsions, treatment of adverse mobility ratio, and wettability modification. Application of chemical-assisted waterflooding for recovery of heavy oil is still an active research topic. A new chemical technology (i.e. IPC Technology as referred to in this paper) has been developed. A proprietary mixture of surfactants is used in several techniques associated with surface extraction as well as in-situ recovery of heavy oil and bitumen. This formulation of solvents and surfactants is reusable, low foaming, non-flammable, not acutely toxic, and non-carcinogenic. The efficacy of using IPC as an additive for waterflooding was presented earlier through a systematic coreflooding study, which showed increased ultimate recovery of different types of oils when compared with commercial surfactant and alkali flooding. In order to investigate the mechanisms behind the enhanced macro-scale oil recovery, a series of pore-scale tests were designed and conducted in this study. Glass micromodel type of porous media was used in the presence of brines with different ion compositions. The pore-scale chemical-assisted waterflooding tests were carried out in four consecutive stages: brine flooding, chemical flooding, soaking period, and extended brine flooding. High quality pore-scale images were captured for qualitative and quantitative analysis of the IPC-assisted waterflooding at the pore-level. IPC intensified water wettability of grain particles in the presence of NaCl; however in the presence of MgCl 2 , use of IPC makes solid surfaces oil-wet. The phenomenon of water-in-oil and oil-in-water emulsification was observed when IPC was used along with different brine compositions. This phenomenon is weakened for lighter oils. When the acid number of the oil was low, extension of soaking period intensified wettability alteration and emulsification mechanisms. Other pore-scale phenomena were also observed during visualization tests such as coalescence of microdroplets during the extended waterflooding stage, snap-off mechanism creating daughter droplets during the extended waterflooding stage, occasional flow of bulk oil films toward the production end, and wettability reversal during various flooding stages. Attempts were also made to conduct statistical analysis of emulsion droplet sizes under different test conditions. Several parameters, including chemical concentration as well as ion concentration in brines, were found to significantly affect the emulsion droplet size distribution. [ABSTRACT FROM AUTHOR]

Abstract Use of chemicals as an additive during steam-based bitumen recovery processes has been an active topic for research and development in the last four decades. In this study, thermo-physical properties of mixtures of bitumen with a newly developed chemical are reported. This new chemical technology (i.e. IPC as referred in this paper) is a proprietary mixture of surfactants that has been used in several techniques associated with surface extraction as well as in-situ recovery of heavy oil and bitumen. This formulation of solvents and surfactants is reusable, low foaming, non-flammable, not acutely toxic and non-carcinogenic. A series of tests were conducted to measure density and viscosity of a bitumen, IPC, and different mixtures of bitumen-IPC at several pressure, temperature and chemical composition conditions. It was observed that solubility of IPC in bitumen was small, and its effects on the oil phase viscosity and density could not be separated from its effects on bulk properties caused by dispersed emulsified droplets of IPC. The impact of IPC on viscosity of mixture was more pronounced than its effect on mixture density. A very complex emulsion was formed upon contact of IPC with bitumen. The results of these tests will be useful in designing a steam-based bitumen recovery process with IPC as the chemical additive. Details of thermal stability analysis of IPC are also presented. Highlights • The effects of IPC formulation on density and viscosity of bitumen-IPC mixtures were studied. • Physical properties and thermal stability of IPC formulation was studied. • IPC formulation had no significant impact on mixture density up to 100 °C. • IPC formulation decreased the mixture viscosity at 100 °C and above. • Complex emulsions were formed upon low temperature mixing of IPC and bitumen. [ABSTRACT FROM AUTHOR]