Experimental investigation of surfactant-stabilized foam stability in the presence of light oil

Abstract

The foam plays an important role in EOR application, while crude oil properties significantly affect foam behavior. In this study we compare the performance of foam generated by two types of surfactant, which in the presence of two light oils. The foaming properties and foam stability, film thickness and emulsified oil effect were fully studied. The final results show that light oil has a positive impact on foam ability of sodium alpha-olefin sulfonate (AOS). However, the alkyl glycosides (APG) did not have the same effect. As the oil saturation increases from 0 to 80%, the light oil has a significant impact on foam stability of APG than AOS. Furthermore, the half-life change degree k is introduced to characterize the change of bulk foam half-life and foam drainage half-life. According to the calculation results, the positive effect of light oil on AOS was reconfirmed. The AOS is more effective in reducing the coalescence of foam and increasing the foam uniformity compared with APG. Moreover, the formation of emulsion has a positive effect on the foam stability. According to the micrograph of foam, the light oil in AOS is emulsified into quite small oil droplets, filling the plateau borders and lamellas. Furthermore, unlike APG, light oil (oil B and C) performed well in thickening the foam film of AOS.