Evaluation of Chemicals Interaction with Heavy Crude Oil through Water/Oil Emulsion and Interfacial Tension Study

Abstract

A new-designed surfactant was formulated to tolerate the harsh conditions of oil reservoirs including high salinity of the formation brine and temperature. The specific emulsion and interfacial tension (IFT) behavior of this new surface active agent were investigated by performing emulsion stability tests, emulsion size analysis, and IFT behavior in the presence of four different types of alkalis. Image processing was utilized to analyze the droplet size distribution using microscopic images of the samples. The results show that depending on the composition of the mixtures, the optimum phase region and interfacial tension behavior change considerably.Solutions containing higher percentage of the surfactant (around 1wt%) show good emulsification capability at different salinities; however, adding any selected alkali to these mixtures reduces the optimum range of salinity tolerance. Mixtures of the surfactant and Triethanolamine exhibit optimum three-phase region at higher salinity conditions compared to other alkaline/surfactant solutions. Increasing the solution salinity reduces the IFT for surfactant solutions however by adding any alkalis the trend was reversed. Considering high values for solubilization-ratio, feasible size of the emulsion droplets, and low IFT values result in promising condition for more oil recovery using a chemical enhanced oil recovery process.

Micro-Emulsion Phase Behavior of a Cationic Surfactant at Intermediate Interfacial Tension in Sandstone and Carbonate Rocks

“…In the pipette tests, the temperature was set to 25 °C and the concentration of C16-TAB was fixed at 3000 ppm, whereas the concentration for the electrolyte (NaCl) was different between various test tubes [26]. The aqueous phase consists of surfactant, sodium chloride, and de-ionized water.…”

“…The aqueous phase consists of surfactant, sodium chloride, and de-ionized water. After adding crude oil to aqueous phase, the test tube was shaken for about 3 min to ensure uniform mixture and then left it undisturbed until the phase boundaries become stable [26] as shown in Fig. The concentration of surfactant is above the critical micelle concentration of 300 ppm as reported by Merck company.…”

Interfacial Tensions of Ethoxylated Fatty Acid Methyl Ester Solutions Against Crude Oil

“…Cationic surfactants are seldom used in oilfield applications because they easily adsorb onto the reservoir rock, are prone to precipitation, exhibit high IFT and have serious toxicity concerns [10][11][12][13]. Anionic surfactants like petroleum sulfonates and alkylbenzene sulfonates result in low oil recovery because of their high Kraft point and poor salt tolerance, which restricts their application [14][15][16][17]. Zwitterionic surfactants usually have excellent properties, however, the cost of production is high making it difficult to apply them in oilfield applications.…”

Phase behavior and interfacial tension evaluation of a newly designed surfactant on heavy oil displacement efficiency; effects of salinity, wettability, and capillary pressure

“…Several parameters have been reported in the literature with the ability to transform micro-emulsion of Winsor type I to type III and type II (or in opposite direction) to find the proper solution salinity and desired ion concentrations [2][3][4][5][6][7]. The most widely used surfactants as the chemical agents nominated for chemically enhanced oil recovery contain two functional groups i.e.…”