Phase Behavior of a New Mixed Surfactant System for ASP Flooding

Ngoc Nguyen


Phase behavior experiments are usually performed to find optimal formulations of injection fluids for a specific crude oil or specific reservoir conditions. In the presented research, a series of experiments on the phase behaviors are conducted in a parametric study. Based on experimental results, the surfactant systems with 0.67 wt% dodecylbenzen sulfonate, 0.33 wt% docusate sodium, 0.4 wt% alcoflood 254S, 1 wt% NaBO2, 1 wt% diethylene glycol butyl ether and 1 wt% methanol are recommended for a high-temperature reservoir with crude oil properties of espo. The data can be used in core-flooding experiments for the next stage of research to confirm the performance factor of enhanced oil recovery.

With crude oil properties of espo, the mixed surfactant ratio of 1:1 is adequate for reservoirs with brine salinity of 3 wt%. However, it should be noted that the authors studied the effect of only NaCl salt on phase behavior. It is recommended that the effect of divalent cations should be evaluated before ASP injection.