Surfactant Solutions Developed for NAPL Recovery in Contaminated Aquifers

摘要: Phase diagrams can be used to select surfactant solutions for diesel dissolution and extraction in contaminated aquifers. They indicate the active matter concentrations which injected into an aquifer. Due precipitation or fine particles dispersion sediments, concentration greater than 5% less their solubility limit injections. Surfactant solution effects on interfacial tension (IFT) are consistent with predictions from phase diagrams. For similar concentrations, IFT lower that dissolve more diesel. values between equilibrated observation of oil-in-water microemulsions column effluents confirm solubilization oil occur a Winsor type I system without mobilization. More 50 sand experiments were done this study good agreement is observed dissolved (with downward injection) predicted However, columns showed significant decrease efficiency drop temperature 25° C 8° (phase predict no change) they essential check efficiencies washing selected by Optimal injection decreases as alcohols ratio (n-AmOH:n-BuOH) increases decreases. In columns, optimal has maximum 0.4 (dissolved diesel/active matter). This limited performance explained by: (1) use water push slug creates dilution thus demixing microemulsion column; (2) area porous media; (3) surface solid phase. Diesel strongly influenced flow direction (up/down), volume solution, lesser extent salinity. Small modifications velocity (three times faster) do not have effect dissolution. Efficiency progresses because (diesel/surfactant solution) The selection recovery based alone but must also consider costs ingredients.