Stability mechanism of a novel three-Phase foam by adding dispersed particle gel

Abstract

A novel three-phase foam as a profile control agent in mature oilfields was successfully prepared by adding dispersed particle gel (DPG). The effects of surfactant concentration, DPG particle concentration, salinity, oil concentration, and the gas-liquid ratio on the foaming capacity of the three-phase foam were systematically investigated. Both the viscosity and surface tension of the surfactant solution were increased when DPG particles were added. Although adding DPG particles caused a slightly negative effect on the solution’s surface tension, the increase in solution viscosity brings significantly positive on foam stability. The DPG particles and surfactant bring a synergistic electrostatic repulsion between the three-phase foam interfaces, which prevented the coalescence of bubbles. By increasing solution viscosity, adsorption at the gas-liquid interface, non-adsorption behavior, and electrostatic repulsion in the solution, the DPG particles effectively stabilized the three-phase foam. An increase in surfactant concentration, DPG particle concentration, and the gas-liquid ratio increased foam volume and decay half-life of the novel three-phase foam, whereas an increase in salinity and oil concentration decreased foam volume and decay half-life. All the above factors affect the surface tension and viscosity of the foaming solution, and thus the abilities to reduce surface tension and increase solution viscosity are the decisive factors for the stability of the novel three-phase foam.