Abstract
In gas flooding, one of the major problems in implementing foam as a gas mobility control method is the stability of foam. Foam booster when blended with surfactant could improve the foam stability. However, the influence of foam booster on the conventional foam stability and foamability at elevated temperature and presence of inorganic electrolytes is not yet explicit due to limited studies in this area. The objective of the present work was to evaluate the influence of a foam booster on aqueous solution stability, foamability and foam stability when blended with surfactant at different ratios at an elevated temperature in the presence of brine composed of monovalent and divalent ions. Three different surfactants AOS C14-16 (alpha-olefin sulfonate), SDS (sodium dodecyl sulfate) and a locally manufactured surfactant 'Surf X' were chosen as base surfactants. An amphoteric surfactant lauryl betaine was chosen as a foam booster in this study. The aqueous solution stability was visually evaluated, whereas the bulk foam experiments were conducted in a commercial foam analyzer apparatus. It was found that not all solutions were stable when lauryl betaine was blended. Lauryl betaine did not improve the foam generation time. The foam stability was improved; however, not all solutions were able to generate stable foam. 'Surf X' was able to generate more stable foam as compared to AOS and when blended with lauryl betaine it also required less amount of lauryl betaine to generate stable foam.