To minimize risks related to ASP flooding at West Salym field, experiments have to be carried out to study surfactant adsorption in the formation. Initially one should develop a necessary and sufficient list of experiments, as well as their conditions and interpretation of results. Therefore, two objectives were set: 1) determine the adsorption of anionic surfactant blend in static conditions adding NaCl, Na2CO3, and polymer within the working range of concentrations; 2) determine the adsorption rate of an ASP formulation in coreflood experiments for water- and oil-saturated cores under formation temperatrue.
The main reliability criterion for the results was the reproducibility of the surfactants adsorption experiments and achieving adsorption values within confidence interval. That is why, development of the methods that allow both to achive reproducibility of the results, and to identify sensitivity factors, is a critical aspect of the experiments.
The work presents an interpretation of the experiments for subsequent modeling of processes using mathematic simulators with the view to evaluate surfactant losses in formation during ASP flooding. The achieved results allow further optimization of the ASP cocktail and return a realistic value for surfactant losses in the course of its filtration, as well as ascertain the economic risks inherent to the project.