Novel surfactant delivery system for controlling surfactant adsorption onto solid surfaces. Part II: Dynamic adsorption tests

摘要

During surfactant flooding in enhanced oil recovery (EOR), surfactant adsorption onto rock surfaces constitutes a serious shortcoming because as the chemical slug flows through the oil reservoir, surfactant is lost to adsorption before it reaches the target residual oil saturation zones, which renders the process technically inefficient and uneconomical. This work is the second phase of a wider study aimed at the evaluation of a new technology to control surfactant adsorption onto solid surfaces by using a surfactant delivery system based on surfactant/-CD inclusion complexes. This complexation was confirmed through surface tensiometry, H-1 NMR and FTIR spectroscopy, and microscopic studies (TEM and SEM). The performance of the surfactant delivery system in controlling surfactant adsorption was evaluated through dynamic adsorption tests using different mixtures of solid adsorbents (sandstone, shale, and kaolinite). Dynamic adsorption data show reductions of surfactant adsorption ranging from 50-92% for all the adsorbents tested; therefore, the surfactant delivery system seems to be highly effective in inhibiting surfactant adsorption onto solid surfaces. This new technology has great potential for EOR chemical flooding applications.