Pore-level visual analysis of heavy oil recovery using chemical-assisted waterflooding process – Use of a new chemical agent

摘要: Abstract Chemical-assisted waterflooding enhances the ultimate recovery of a conventional process through several mechanisms such as reducing interfacial tension between water and oil, formation in-situ emulsions, treatment adverse mobility ratio, wettability modification. Application chemical-assisted for heavy oil is still an active research topic. A new chemical technology (i.e. IPC Technology referred to in this paper) has been developed. proprietary mixture surfactants used techniques associated with surface extraction well bitumen. This formulation solvents reusable, low foaming, non-flammable, not acutely toxic, non-carcinogenic. The efficacy using additive was presented earlier systematic coreflooding study, which showed increased different types oils when compared commercial surfactant alkali flooding. In order investigate behind enhanced macro-scale recovery, series pore-scale tests were designed conducted study. Glass micromodel type porous media presence brines ion compositions. carried out four consecutive stages: brine flooding, soaking period, extended High quality images captured qualitative quantitative analysis IPC-assisted at pore-level. intensified grain particles NaCl; however MgCl2, use makes solid surfaces oil-wet. phenomenon water-in-oil oil-in-water emulsification observed along weakened lighter oils. When acid number low, extension period alteration mechanisms. Other phenomena also during visualization coalescence microdroplets stage, snap-off mechanism creating daughter droplets occasional flow bulk films toward production end, reversal various flooding stages. Attempts made conduct statistical emulsion droplet sizes under test conditions. Several parameters, including concentration brines, found significantly affect size distribution.