Electrochemical Analysis of Surfactants for Enhanced Oil Recovery. Final Report

摘要

Surfactants are being considered by the oil industry as one means of achieving enhanced oil recovery (EOR) from oil reservoirs. The process involves injection of a surfactant solution that is designed to provide interfacial tension low enough to mobilize the discontinuous oil phase in a reservoir after secondary waterflood operations. Maximum success with such a process requires, among other things, that the surfactant be propagated through the entire reservoir from the injection well to the production well with a minimum of surfactant loss to the rock surface due to adsorption. The objectives of this project have been first, to determine if an electrochemical means of surfactant quantitative analysis could be developed which would give accurate results over a wide range of concentration in applications relating to tertiary oil recovery and second, to initiate surfactant adsorption studies, using this electrochemical technique as appropriate. The development of an electrochemical technique has been only partially successful. An indirect technique previously reported in the literature was modified for application to microemulsion systems that may include, in addition to surfactant, oil, alcohol, and brine components. Reasonable calibration curves were obtained for sodium dodecylbenzene sulfonate and a monoethanolamine (MEA) alkylorthoxylene sulfonate that has been used for enhanced oil recovery studies. Further development of the method for continuous adsorption studies, however, has been limited by problems with obtaining consistent results from the nitration reaction required for the technique. (ERA citation 08:006930)