Surfactants Selections Criteria for Enhanced Oil Recovery in High Temperature and High Salinity Environment

Abstract

Surfactants are used as suspending and foaming agents. Crude oils deposited and found in sandstone and high temperature environment are often very light. But, Pore throats restrictions made it difficult for such oil to flow unaided. Specially designed surfactants, called IbileSurfac, will serve as a carrier to crude oil, while overcoming barriers posed by saline water. This study was primarily conducted on locally sourced surfactants, called IbileSurfac. IbileSurfac, together with Tween 80, Teepol, and Lauryl Sulphate were screened with NaCl-only brines and n-octane fluid at a unitary value of water/oil ratio for temperatures between approximately 900C and 120°C; at intervals of 5°C. All test cases were performed in the absence of methanol or ethanol (No alcohols present) and other co-solvents, in a Pressure-Volume-Temperature cell. Both volume and pressure were kept constant. Varying phase behavior was observed for each class of surfactants, with minimum salinity value of 0.001parts per thousand and maximum value of 0.002 parts per thousand of NaCl for IbileSurfac and others. IbileSurfac has highest Oil solubilization, and lowest in Teepol, with Tween 80 and Lauryl Sulphate, maintaining middle positions. The test results for 120°C at unitary-water-oil-ratio (WOR) show that Ibile Surfac homogenized to form transparent and aqueous single phase liquid, which can flow easily through pore throat restrictions. This provides a useful lead for initial selection of appropriate surfactants for EOR processes. IbileSurfac is very promising because it has a natural structure that needed the least comparative treatment cost for high temperature and saline environment.

Orange Mesocarp Extract as a Natural Surfactant: Impact on Fluid–Fluid and Fluid–Rock Interactions during Chemical Flooding

“…Chemical enhanced oil recovery (CEOR) describes processes that involve the use of chemicals such as surfactants, alkali, and polymers in oil recovery with the aim of increasing the capillary number which in turn reduces the interfacial tension (IFT) values between oil and brine, reducing the mobility ratio, gathering the residual oil, and increasing the sweep efficiency. Effective use of these chemicals is subject to certain inherent attributes of the reservoir such as reservoir type and depth and concentration and salinity of the formation brine . In surfactant flooding, surface-active agents are used to reduce the IFT between two phases while also altering the wettability of the reservoir rock .…”

“…Effective use of these chemicals is subject to certain inherent attributes of the reservoir such as reservoir type and depth and concentration and salinity of the formation brine. 2 In surfactant flooding, surface-active agents are used to reduce the IFT between two phases while also altering the wettability of the reservoir rock. 3 Some successful field applications of surfactant flooding include Tanjing field in Indonesia, Bentiu field in South Sudan, and Yates field in Texas (USA), which resulted in enhanced oil recovery as well as reduced IFT.…”

Laboratory Investigation of Polymeric Surfactants for EOR in High Salinity and High Temperature Reservoir

“…Thus, surfactant-polymer flooding allows the attainment of the synergetic effect of low interfacial tension and mobility control with minimal side effects (primarily the elimination of possible scaling due to Alkaline addition). The works of Ghosh et al (2013), Adeniyi et al (2015), and Quadri et al (2015) are among recent efforts to develop appropriate surfactants and polymers for EOR application in high salinity and high temperature conditions. Recent efforts have also focused on understanding the associated mechanisms and phenomena in order to enlarge the window of surfactant-polymer application especially toward high salinity and high temperature carbonates (Han et al 2011;AlSofi et al 2012;Han et al 2014;Wu et al 2015).…”