Hydrophobic modified silica particle (HMSP)-stabilized cottonseed oil emulsion for oil recovery enhancement

In this work, a novel water plugging agent, hydrophobic modified silica particle (HMSP)-surfactant-stabilized cottonseed oil emulsion, for oil recovery enhancement was developed. The stability and rheology experimental results displayed that the synergistic interaction between the HMSP and surfactant was formed, which could remarkably improve the stability and increase the viscosity of the emulsion system. The microscopic visualization tests suggested that there was a bicontinuous structure in the HMSP-surfactant-stabilized emulsion. Moreover, the sand pack flooding tests showed that the sweep and displacement efficiency could be significantly enhanced after HMSP-surfactant-stabilized emulsion injected. The blocking rates of HMSP-surfactant-stabilized emulsion and individual surfactant-stabilized emulsion are 98.7% and 52.9%, respectively. The above results can be considered as a guidance in the design and studies of HMSP-stabilized emulsion for a selective plugging.