Some research work on phase test was carried out with cross-test design

using Alkanolamide Sulfate System Combined With Alkylalcoholamide as surfactant

selected Kelamayi crude oil as oil phase

the composition of composite deoil system was obtained. The factors affecting surface tension and the synergic effects were studied by determination of instantaneous interface tension. The alkaline-surfactant combination flooding system containing the surfactant

sodium chloride and alkali can produce ultra-low interfacial tension (10\{-3\}mN/m order) against Kelamayi crude oil.