In this study, interfacial tension (IFT) is measured between brine and crude oil (a sample of heavy oil from an Iranian oil reservoir) in the presence of two nonionic surfactants, KEPS 80 (Tween 80) and Behamid D, at different concentrations in order to optimize the concentrations of the surfactants. The surface response method is used to design the IFT measurement experiments. The experimental design and optimization is performed using the IFT as an objective function and temperature, concentration, and time as independent variables. In addition to the IFT measurement, various experiments such as stability tests of the surfactants in NaCl brine solutions, adsorption experiments on the carbonated rock surface, and phase behavior tests are performed to investigate the behavior of KEPS 80 and Behamid D in the enhanced oil recovery process. At the end, a model using the response surface statistical technique is designed for optimization of the concentrations of the surfactants, and a surfactant molecular migration mechanism is used for explanation of the dynamic IFT variation versus time. In the case of IFT experiments, the effect of surfactant concentration (at 1000, 3000, and 5000 ppm) on the dynamic IFT is investigated. The experiments are performed at four temperatures (25, 40, 50, and 67°C). The results show that the oil–brine IFT values can be reduced to about 4 mN m⁻¹ in the presence of Behamid D and to about 1 mN m⁻¹ in the presence of KEPS 80 at low concentrations.

中文翻译：

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非离子表面活性剂存在下原油-盐水体系动态界面张力的优化

在这项研究中，在两种非离子表面活性剂KEPS 80（吐温80）和Behamid D的存在下，在两种非离子表面活性剂的存在下，测量盐水和原油（来自伊朗储油厂的重油样品）之间的界面张力（IFT）。为了优化表面活性剂的浓度。表面响应方法用于设计IFT测量实验。使用IFT作为目标函数，并使用温度，浓度和时间作为自变量进行实验设计和优化。除了进行IFT测量外，还进行了各种实验，例如NaCl盐水溶液中表面活性剂的稳定性测试，碳酸盐岩表面的吸附实验以及相行为测试，以研究KEPS 80和Behamid D在提高采油率方面的行为。处理。与时间的关系。在IFT实验的情况下，研究了表面活性剂浓度（在1000、3000和5000 ppm时）对动态IFT的影响。实验在四个温度（25、40、50和67°C）下进行。结果表明，在Behamid D存在的情况下，油盐水IFT值可以降低至约4 mN m ^-1，在低浓度存在KEPS 80的情况下可以降低至约1 mN m ^-1。