Foaming Properties of Laurel Amide Betaine in High Temperature and High Salinity Oil Reservoirs

Laurel amide betaine (LAB) has good foaming properties under high temperature (90 degrees C) and high salinity (220 000mg/L. In this paper, foaming properties of LAB were investigated comprehensively. The results showed that at low concentrations, LAB had good foaming properties and pH value had little effect on foaming properties. With an increase of NaCl or CaCl2 concentration, drainage half-life increased linearly. At 90 degrees C, with the increase of water salinity, critical micelle concentration (CMC) decreased. Thus, at the same surfactant concentration, the higher the salinity, the larger the CMC times, one reason for longer drainage half-life. A change in the Na2SO4, concentration has little effect on foam stability. The LAB had relatively low adsorption value and could alter wettability from oil-wet to water-wet.