Laboratory Study On Homogeneous Microemulsion Flooding

Chemical flooding is the later stage of water flooding oilfield development important EOR technology,polymer flooding in low permeability oil field because of difficult injection,fingering phenomenon is serious and will pollute the ground environment;alkaline flooding can cause alkali consumption and production of limited surfactant,microemulsion flooding oil technology as the concentrated surfactant flooding technology,which has an important guiding significance for the improvement of low permeability oil and gas reservoirs of oil displacement efficiency.Using anionic surface active agent in our laboratory as the main ingredient, by orthogonal experiment optimization design, to get the best formula of Homogeneous microemulsion is 2.5% XSY,8% alcohol,5%~6% Na Cl,the volume of octane and water is 5ml,the best formula of microemulsion has good solubilizing ability, and the interfacial tension between oil and water can be reduced 10-3m N/ m magnitude, good stability and strong ability of injection etc.Using alcohol scanning method and salinity scanning method for salt type and concentration,the type and concentration of alcohol,temperature and p H on the formation of microemulsion phase,the solubilization capacity and interfacial tension are studied.The injection style and injection slug size of microemulsion,different water flooding velocity foy the impact on oil displacement efficiency by core experiments are studied.The experimental results show that:the microemulsion slug can improve the recovery rate from 10% to 15%,with the increase of the Micronesian injection slug,increase almost linearly increase recovery rate,and with the increase of water flooding velocity,two times water flooding after the micronesian injection slug increasing recovery rate decreases.