Optimal design of pickering emulsions for heavy-oil recovery improvement

Abstract

This study focuses on the ability of complex colloidal solution to enhance heavy oil recovery by stabilizing a heavy oil-brine Pickering emulsion. After testing many different combinations of anionic surfactants, and cationic surfactants, and nano-particles, we formulated the best stability options and created oil-in-water Pickering emulsions stabilized by silica, a cationic surfactant [dodecyltrimethylammonium bromide (DTAB)], and an anionic surfactant [alcohol propoxy sulfate (Alfoterra S23-7S-90)]. Then, we conducted various core flooding experiments in order to demonstrate the practical ability of the created emulsion system and observe its capacity to enhance oil recovery. Rate-dependency flooding tests were also conducted to determine the optimal flow rate (shear rate) required for heavy oil production through emulsification for different permeability media. Various permeability media were selected in this research to test the dynamic nature of the solution, including slim tube sandpack of which provides more challenging conditions for emulsification due to its length (1 m). We conducted the slim tube sandpack flooding experiment was conducted at the optimal rate to confirm in-situ emulsion generation and to support the potential use of the chemical combination in the heavy oil industry.

Graphical Abstract

Keywords:

• Microemulsion formulation
• emulsion stability
• surfactants and polymers
• nanofluids
• cold heavy oil recovery
• dynamic flooding experiments

Additional information

Funding

This research was conducted under the second author’s (TB) NSERC Industrial Research Chair in Unconventional Oil Recovery (industrial partners are Petroleum Development Oman, Total E&P Recherché Développement, SiGNa Oilfield Canada, Husky Energy, Saudi Aramco, Devon, APEX Eng. and BASF, and an NSERC Discovery Grant (No: RES0011227).