Publications Scientifiques
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Item A review of emulsion flows, their characterization and their modeling in pumps(Institution of Chemical Engineers, 2024) Achour, Lila; Specklin, Mathieu; Asuaje, Miguel; Kouidri, Smaine; Belaidi, IdirIn the engineering field, emulsions and liquid–liquid two-phase flows within centrifugal pumps are generally unwanted as emulsions will have negative effects on pump operation. Besides, emulsions are usually formed when the oil and water phases are brought together in a process called emulsification, which is enhanced by high shear rates. This topic has been extensively researched over the past decades, with sophisticated theories regarding the phenomena involved in emulsions formation and characterization in pumps. Besides, given the complexity of the physics governing emulsions, studies on their modeling within pumps, based on empirical correlations or computational fluid dynamics models, are insufficient and remain limited. This review aims to provide a complete overview of investigations on liquid–liquid flow in centrifugal pumps. Characteristics of these mixtures, such as stability, phase inversion, droplet size distribution and rheological behavior, are discussed. Current approaches and techniques for analyzing pump performance handling emulsion and two-phase liquid–liquid flow are reviewed thoroughly. The limitations of the existing models are studied, and potential future developments are proposed.Item Seismic Inversion and Lithological Characterization of Reservoirs: Case of Penobscot, Nova Scotia Offshore (Canada)(Springer Nature, 2024) Oumarou, Sanda; Mabrouk, Djeddi; Tabod, Tabod Charles; Marcel, Jean; Essi, Jean Marcel Abate; Mebenga, Thibaut Aloys Ekani; Ngos, SimonSeismic inversion is a method of processing seismic data to predict different properties of rocks such as density, compressibility, velocity, water saturation, porosity, permeability, and layer thickness. This is how it seems important to us to use seismic inversion to characterize the nature of reservoir rocks. This work uses the different types of seismic inversion that are related to AVO analysis to perform lithological analysis of hydrocarbon reservoirs using 3D seismic data from Penobscot located in offshore Nova Scotia (Canada). These are elastic inversion, acoustic inversion, and inversion by attributes which constitute the methods used. The results allow good discrimination of different layers of hydrocarbon reservoirs using a combination of attributes. Thus, the cross-plotting of the density and the Poisson ratio made it possible to highlight four facies.Item A novel spherical hybrid material based on the combination of humic acid/alginate/Algerian Zeen Oak sawdust for removing chromium (VI) from wastewater(Elsevier, 2023) Sadoun, Louiza; Benmounah, Abdelbaki; Ait-Ramdane-Terbouche, Chafia; Seffah, Karima; Terbouche, AchourA novel spherical hybrid material designed from the combination of humic acid (HA), sodium alginate (Al) and sawdust derived from Algerian Zeen Oak Waste (OS) has been prepared. After optimization of HA/Al/OS mass ratio, the structure of the synthesized hybrid spheres was established using various characterization techniques notably ATR, SEM-EDX, XRD, BET and the point of zero charge (pHpzc). Adsorption tests using this compound were applied to remove chromium(Cr (VI)) from aqueous solutions. The influence of the different parameters such as contact time, pH, temperature, initial metal concentration, and mass of the material were studied. The obtained results revealed that the mass of HA had a significant influence on the formation of the spheres. By varying the ratio of HA/Al/OS (1/16/16 (S1), 1/5/5 (S2), 1/3/3 (S3) and 1/2/2 (S4)), the humic acid allowed a good coating of the hybrid material. The ratio 1/5/5 (S2) was retained for the adsorption study. The efficiency of this material was subsequently tested for the removal of Cr (VI) from aqueous solutions. Optimizing the different experimental parameters allowed to obtain a removal efficiency of over 90 % for an initial Cr (VI) concentration of 60 mg L−1, at pH = 2 and temperature of 353.15 K, using 0.1 g of material. The kinetic study showed that the process of elimination of Cr (VI) followed the pseudo-second order model and well fitted with the Freundlich adsorption isotherm model with R2 value of 0.99 and a low value of χ2 (2.88). A maximum adsorption capacity of 50.328 mg.g−1 was determined by the Langmuir isotherm model. The hybrid spheres showed good regeneration efficiency even after four adsorption-desorption cycles. The thermodynamic study (ΔS = 0.091 kJ mol−1 K−1, ΔH = 24.427 kJ mol−1 and ΔG° = −2.883 kJ mol−1 at 298.15 K) revealed that the adsorption process was spontaneous, favorable and endothermic with a physisorption phenomenon. Finally, the adsorbent was successfully applied to real wastewater contaminated with chromium. This application has proved high removal efficiency of Cr (VI) and a yield of 94.31 % was obtained at 40 °C.Item Characterization of used engine oil and possibility of recovery(2018) Zerdane, Youghourta; Hachemi, M.; Tazrout, M.; Largeau, Jean-FrançoisThe world today is facing major energy and climate challenges. The growth of global energy demand, the decline in fossil reserves and the dangerous disruption of the climate caused by pollution compels states and scientists to quickly adopt plans strengthened action on renewable energies and the treatment of different types of waste generated by human activity, such as used motor oils in order to preserve the environment and to find other sustainable and economically viable solutions. This work, based on a characterization study of used motor oil, has shown that these characteristics deteriorate after a certain time of use compared to a new oil and that they become polluting due to contamination by inorganic elements (metal). The high calorific value of the used oil can be considered as an important source of energy, hence the need to develop a process for the upgrading of this waste and for this purpose it is envisaged to explore later one of these ways which is pyrolysisItem Synthesis, characterization and application of tetragonal BaTiO3-δ in adsorption and photocatalysis of congo red(Elsevier, 2023) Merrad, S.; Abbas, Moussa; Brahimi, R.; Bellal, B.; Trari, M.The synthesis by a simple approach of the deficient Barium Titanate BaTiO3-δ (BTO) crystallizing in a perovskite structure is reported along with the physicochemical properties. Thermal analysis (TG/DSC) was performed to elucidate the synthesis process. The X-ray diffraction (XRD), BET analysis, scanning electron microscopy (SEM-EDS) and electrochemistry were investigated. The catalyst revealed a single phase with a tetragonal symmetry obtained by treatment at 650 °C. The direct band gap (3.34 eV), obtained from diffuse reflectance spectroscopy (DRS), is assigned to the charge transfer O2-: 2p-Ti4+: 3d. The electrical characterization indicated a non-degenerate conductivity due to oxygen vacancies with an activation energy of 0.33 eV. The capacitance measurements indicated n-type behavior with a flat band potential (Efb) of − 0.43 V and a carrier concentration (ND) of 3.90 1018 cm−3. The photocatalytic process was elucidated by the electrical impedance spectroscopy (EIS). The performance of BTO was assessed by a combination of the adsorption of Congo Red (CR) followed by its degradation under UV light. The photodegradation kinetic was well fitted by a pseudo-first-order model with an abatement of 50% and 91% under UV and solar lights respectively. Different scavengers were used to evaluate the reaction mechanism and the radicals O2•- are the main reactive species of the CR oxidation. Four regeneration cycles demonstrated the catalyst stability. A degradation mechanism was established based on the scavengers effectItem Chemical characterization of asphaltenes deposits from Hassi Messaoud field(Elsevier, 2022) Behnous, Dounya; Bouhadda, Youcef; Moffatt, Brian; Zeraibi, Noureddine; Coutinho, João A.P.The precipitation and deposition of asphaltenes are complex phenomena that reduce the efficiency in oil production operations. In this study, spectroscopic and thermal methods were used for the characterization of asphaltene samples extracted from deposits belonging to different locations in the Hassi Messaoud field. Structural parameters and the chemical structure of the studied asphaltenes were determined using 13C solid nuclear magnetic resonance (NMR), X-ray diffraction and Raman spectroscopy. The thermal behavior of the asphaltenes studied was examined using differential scanning calorimetry. The results obtained suggest that island is the predominent architecture for the asphaltenes studied with an average of 7 to 8 fused rings and aliphatic length chain of about 3–4 carbons. The number of aromatic sheets in a stacked cluster (N) is between 7 and 8 sheets. The aromatic sheet diameter of the four samples ranges from 12.18 to 15.52 Å with an average interlayer distance between aromatic sheets of 3.52 Å and an average interchain layer distance of 4.48 ÅItem Study of the adsorption of methylene blue by natural materials (olive stone, date pit and their mixture) in fixed bed column(ALJEST, 2019) Abed, Fatma; Aksa, H.; Abai, N.; Babakhouya, N.The present study focuses on the recovery of two agro-food waste available in our country with significant quantities olive pomace and date pits for the removal of a synthetic dye which is methylene blue. Both materials were used in their native forms separated and mixed to improve their adsorptive capacity. A range of physico-chemical analysis was performed to characterize adsorbents used, among them: the FTIR spectroscopy and the scanning electron microscopy. The ability of adsorbents prepared to adsorbe methylene blue (MB) from the aqueous solution was investigated in a fixed bed column. The effects of several important parameters were studied, such as initial concentration of MB, flow rate and bed height. The corresponding breakthrough curves were calculated.Item Application of Fourier Transform Infrared (FT-IR) Spectroscopy to the Study of the Modification of Epoxidized Sunflower Oil by Acrylation(Sage journals, 2012) Irinislimane, Ratiba; Belhaneche-Bensemra, NaimaCommercial sunflower oil was epoxidized at the laboratory-scale. The epoxidized sunflower oil (ESFO) was modified following the acrylation reaction. Modification was carried out simultaneously using acrylic acid (AA) and triethylamine (TEA). To optimize the reaction conditions, the effects of four temperatures (40, 60, 80, and 100 °C), the ESFO:AA (100:100) ratio, and 0.2% TEA were investigated. The rate of conversion was analyzed with both FT-IR and titration of the oxirane ring. After that, the temperature with the highest conversion was selected and used throughout for all modification reactions. Then, four ratios (100:100, 100:90, 100:80, and 100:75) of ESFO:AA were analyzed at four different concentrations of TEA (0.2, 0.3, 0.4, and 0.5%) to determine the best estimate for both the ESFO:AA ratio and the catalyst concentration. Conversion rate was analyzed using FT-IR spectroscopy by measuring the concentrations of ester, carbonyl, and alcohol groups. Moreover, oxirane***ring concentration was estimated using the titration method (with gentian violet as indicator) and FT-IR spectroscopy (epoxy ring absorptions at 1270 cm−1 and 877 cm−1). Based on conversion yield, the optimum ESFO:AA ratio corresponds to 100:80; the best temperature reaction was at 60 °C, and the best TEA concentration was 0.2%. The critical amounts of reactants needed to reach maximum conversion were established. The final acid value of the acrylated ESFO after washing (pH = 7) was 2.1 mg potassium hydroxide (KOH) g−1. All results show that FT-IR spectroscopy is a simple, low-cost, rapid method for investigating the kinetics of a reactionItem Characterization of the interface of a Non-Ferrous dissimilar realized by rotary friction welding(Springer, 2021) Mebtouche, A.; Bezzazi, Boudjema; Ramou, N.; Aboudi, D.; Faci, Y.; Latef, M.The need for assembly between dissimilar materials often arises in complex industrial applications. It avoids problems inherent in conventional welding. Therefore, in this study the performance of welded joints developed using a rotary friction welding machine, between Cu/Al, are characterized. The interface of the welded assembly of dissimilar copper Cua1 and AA2014 aluminum, consists of several intermetallic compounds mainly CuAl2, CuAl and Cu9Al4. Dendrites have been revealed, this structure is known to be the result of solidification. While rotary friction welding is done at the solid state. In this work, we seek to know the phenomena that take place during the entire process and in the creation of the interface. This article presents the study of the Al/Cu interfacial structure of welded joints made by rotary friction in a modified cycle with two stepsItem Activation et caractérisation d‘une zéolithe HY utilisée en qualité d’adsorbant(Aljest, 2018) Cherifi-Naci, HalimaL’article traite la préparation des matériaux zéolithiques activés dotés d’un pouvoir adsorbant très important dans le domaine de l’environnement. Nous avons procédé à la caractérisation physico-chimique et à la détermination des conditions optimales d’Activation (Concentration : 5M à la température T=90°C, Temps d’activation= 4h, Quantité d’H2SO4 adsorbée=1,75meq/g d’argile, Capacité d’échange cationique : CEC=70meq/100g d’argile, Surface spécifique=950 m2/g) en vue d’obtenir des zéolithes HY activées très performantes utilisées en qualité d’adsorbants. Les zéolithes HY activées ont été caractérisées par les techniques suivantes : Fluorescence X (pourcentage atomique), Diffraction des rayons X, le Microscope électronique à balayage et par des analyses physico-chimiques (Capacité d’échange cationique, la masse volumique, l’indice d’acidité, la surface spécifique et le diamètre moyen des pores).D’après les résultats des diffractogrammes RX , les zéolithes HY activées ne subissent aucunes modifications chimiques ni la destruction de leur réseaux cristallins et la création d’une structure cristalline plus uniforme .Les diamètres moyen des pores des zéolithes activées : Zéolithe HY à5M/70°C,Zéolithe HY à5M/90°C,Zéolithe HY à7M/70°C sont de l’ordre de 14,74 ; 15,02 et 17,01 A°, respectivement et leurs surfaces spécifiques sont de l’ordre de 650 ; 950 et 995 m2/g, respectivement. Les propriétés physiques des matériaux zéolithiques étudiés montrent une augmentation de la surface spécifique, la masse volumique et la porosité (diamètre moyen des pores) après traitement de la zéolithe HY par différentes concentrations à l’acide sulfurique, ces résultats confirment l’amélioration de la structure microporeuse et la création d’un réseau de tamis moléculaire plus développé. Avec les propriétés structurales et texturales déterminées, on peut conclure que les zéolithes activées ainsi obtenues sont des matériaux très réactifs et peuvent être utilisés dans des processus de dépollution des eaux usées industrielles