An experimental study on ASP process using a new polymeric surfactant

This paper presents an alternative chemical
formulation using a new polymeric surfactant to improve
the conventional alkali/surfactant/polymer (ASP) flooding.
It is a one-component system for interfacial tension
reduction and viscosity control. To simulate the conventional ASP flooding, the performance of the polymeric
surfactant was studied in the absence and presence of
sodium carbonate. The most outstanding feature of the new
polymeric surfactant lies in its viscosity insensitivity
towards an increasing alkali concentration up to 1.2 wt%.
This feature makes the new formula superior to the conventional ASP process. A combination of alkali and surfactant with a concentration of 0.8 and 0.4 wt% was found
to significantly reduce the interfacial tension while maintaining the desired solution viscosity. The optimal polymeric surfactant concentration was then validated in
coreflood experiments using different surfactant concentrations. Using the optimum surfactant and alkali concentrations, tertiary oil recovery could reach 16.3 % of the original oil in place by injecting a 0.5 pore volume of the formulated slug. This makes the new polymeric surfactant
promising because it has structural feature that can be
modified to give a width range of interfacial tension
reduction and viscosity control to suit reservoir conditions.