Publications Scientifiques

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    Effect of concentration and temperature on the rheological behavior of hydroxylethyl cellulose solutions
    (2022) Remli, Samia; Benyounes, Khaled; Benmounah, Abdelbaki
    The knowledge of the rheological properties of polymers makes their use interesting in various fields of applications, such as food industry, cosmetics, enhanced oil recovery or construction materials. Whatever the application, the effect of temperature and concentration on these properties is of great importance. This study covered a wide range of concentrations from 0.2 w/% to 1 w/%, and temperatures from 10 °C to 80 °C. The results obtained provide interesting information regarding the effects of the temperature and concentration of the aqueous solutions of the polymer since they reveal that the rheological properties remained practically unchanged in the temperature range considered. The impacts of shear rate, temperature and concentration on the flow behavior were analyzed. Small-amplitude oscillatory shear measurements were performed, and the results obtained show that the apparent viscosity is strongly influenced by the concentration of the aqueous solution of HEC, exhibiting a marked non-Newtonian shear-thinning behavior at different temperatures. The flow behavior is well described by several rheological models. The effect of temperature on the kinematic viscosity was fitted with the Arrhenius model; the behavior of this model in relation to experimental viscosity values was suitable and the linear fit showed good regression coefficients. The dynamic state was well described with the generalized Maxwell model
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    Rheological behavior and microstructural properties of crude oil and emulsions (water/oil-oil/water)
    (Taylor & Francis, 2024) Yacine, Celia; Safri, Abdelhamid; Djemiat, Djamal Eddine; Benmounah, Abdelbaki
    An experimental study on crude oil (from the Tin Fouye Tabankort oil field in southern Algeria) was carried out. This study allowed us to understand the rheological behavior of this crude oil with these different emulsions and how it reacts under the effects of temperature and the inversion of its phase from E/H to H/E. So we measured the rheological characteristics by tests flow and dynamic mode at different temperatures from 10 °C to 50 °C and at different water concentrations (20.40.50.60 and 70%) at a fixed temperature of 20 °C. The increase in temperature results in a 31.84% reduction in the initial viscosity of the crude oil. The addition of the volumic fractions of water results in an increase in viscosity at the point of inverse, which will decrease the apparent viscosity of these emulsions where the emulsions (W/O) come from (O/W). This crude oil and their emulsions exhibit a non-Newtonian behavior with shear thinning. The dynamic analysis depends on the temperature and the percentages of water added to the crude oil. At the end, a microscopic analysis was added to verify the relationship between the shape and diameter of the water droplets in each emulsion and the viscosity variation.
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    A review on the rheology of heavy crude oil for pipeline transportation
    (ELSEVIER, 2020) Souas, Farid; Safri, Abdelhamid; Benmounah, Abdelbaki
    Given the combination of rising global energy demand and the decline in conventional crudes, heavy crudes are generally considered to be the future energy resource. In many regions of the world, heavy crude oil must be transported through pipelines from the point of production to storage facilities or refineries. The transportation of heavy crude oil by pipeline poses serious problems related to the high viscosity and flow difficulties, particularly in cold climates or offshore conditions. Indeed, the viscosity of crude oil is an important physical property that influences and controls crude oil flow in pipelines. Viscosity introduces resistance to movement by causing a shear or frictional force between the fluid particles and the boundary walls. This high viscosity means that the pumping power requirements for crude oil in a long-distance pipeline are very high in order to overcome the increasing shear and friction forces. Therefore, in order to facilitate the pumping of these viscous oils and reduce operating expenses and the negative impact of pressure drops in pipelines during flow and processing, their viscosity must be reduced. Various techniques are used to increase pumping efficiency and improve the flow of crude oil through the pipeline, which may present logistical, technical or economic disadvantages for a given application. The main ones are the addition of surfactants or polymers, dilution with lighter crudes, use of water as annular fluid, thermal remediation and emulsification with surfactant (O/W). This review highlights the methods currently used to enhance the fluidity of heavy crude oil in pipelines behind rheology improvement, in particular the addition of additives and the use of water and surfactants to create a stable emulsion of heavy crude oil in water have been considered.