Browsing by Author "Husein, Maen M."

Now showing 1 - 11 of 11
  • Thumbnail Image
    ItemOpen Access
    Conversion of Petroleum Coke to Porous Materials
    (2019-12-13) Wu, Jingfeng; Hill, Josephine M.; Husein, Maen M.; Lu, Qingye
    Petroleum coke (petcoke) is a low value by-product from oil and gas refinery. The production of oil sand petcoke has been continually increasing over the last 20 years. However, only 11-20% of the petcoke produced has been utilized as site fuel. The remainder has been largely stockpiled in northern Alberta. As oil sand petcoke contains higher carbon but a lower ash content compared to conventional crude oil petcoke, this project was designed to prepare porous carbon materials from petcoke. The aim of this thesis was to develop methods to convert by-products from oil refinery (eg. petcoke and asphaltenes) to value-added porous carbon materials. In order to combine nanoscale pores and macroscale pores into one monolithic structure, activation was proposed to develop micro and mesopores on oil sand petcoke as a first step. Both chemical activation (using KOH/NaOH) and chemical steam co-activation were studied to prepare activated carbon (AC) from petcoke. A salt template was then utilized to form macroscale pores between AC particles for hierarchical porous carbon (HPC) preparation. The co-activation of KOH and steam reduced the chemical agent amount without compromising pore volume. Before steam was introduced into the system, a molten phase around petcoke particles is presumed to be formed. A greater amount of chemical agent corresponded to a thicker molten chemical layer, which restricted the rate of steam gasification. By lowering the activation temperature to 500 ˚C, a 0.34 cm3/g pore volume and 800 m2/g surface area were obtained with an AC yield of 94%. Since there was almost no carbon consumption, the pores developed at 500 ˚C were most likely due to the opening of initial closed pores of petcoke. Finally, by using asphaltenes as natural binders to connect non-washed AC particles, HPC was fabricated with multiple scale pores after washing away the salts. The experimental results in this thesis provide feasible approaches to prepare porous materials from petcoke and asphaltenes. A better understanding of pore development during the activation process will help to optimize the process and control the properties of the final product.
  • Thumbnail Image
    ItemOpen Access
    Developing Cold Flow Technology for Pipeline Transportation of Paraffinic 'Waxy' Mixtures
    (2019-04-29) Haj-Shafiei, Samira; Mehrotra, Anil K.; Husein, Maen M.; Karan, Kunal
    The terms hot flow and cold flow refer to the bulk temperature of a ‘waxy’ crude oil being above and below its wax appearance temperature (WAT), respectively. The deposit thickness has been reported to decrease substantially when the crude oil in a pipeline is in the cold flow regime and the deposit thickness approaches zero when the crude oil temperature is the same as the surrounding temperature because of the absent of temperature driving force. The cold flow regime was characterized by two-phase flow, in which solid wax crystals are suspended in the liquid phase. However, achieving cold flow of a ‘waxy’ crude oil would invariably involve solid deposition on the cooling surface especially in the hot flow regime. This thesis is focused on understanding and developing the cold flow technology for pipeline transportation of paraffinic ‘waxy’ crude oils. Solids deposition in the cold flow regime from a wax–solvent mixture was studied experimentally using a cold finger apparatus to develop stable two-phase solid-in-liquid suspension and to prove the reduction of deposit thickness in the cold flow regime. This study further investigated a novel methodology for accomplishing cold flow condition without any significant deposition in the hot flow regime using both cold-finger and flow-loop apparatuses. In this approach, the effect of cooling rate was investigated on the temperature difference between the mixture and the coolant as well as the extent of wax deposition. It was found that the temperature difference and the deposit mass increased with the cooling rate. With a constant temperature difference, no deposition was observed above the WAT. The results indicated that the deposition in the hot flow regime could be decreased substantially, or even be avoided when the waxy mixture is cooled at a low cooling rate. In addition, a steady-state heat-transfer model along with the effect of deposit aging was developed for the formation of a deposit-layer from wax–solvent ‘waxy’ mixtures in a pipeline under turbulent flow. The trends in the model predictions compared satisfactorily with those reported from bench-scale experimental studies as well as the predictions from an unsteady-state moving boundary problem formulation.
  • Thumbnail Image
    ItemOpen Access
    Evaluation of Measurement Techniques for the Adsorption of Asphaltenes onto Metal Oxide Nanoparticles
    (2018-05-22) Ezeonyeka, Nkiru Lucia; Husein, Maen M.; Yarranton, Harvey William; Hill, Josephine Mary
    The adsorption of asphaltenes onto nanoparticles (NPs) has received a lot of attention in the recent years owing to its important application in areas such as heavy oil recovery. The effect of the measurement technique on the adsorption isotherms has never been addressed, however. In this work, the adsorption of n-heptane-precipitated asphaltenes, C7-asphaltenes, from toluene model solutions onto three metal oxide NPs; namely Fe2O3, Fe3O4, and Al2O3, was studied. Most results on asphaltenes adsorption employed UV-Vis spectroscopy, especially when using conventional adsorbents. More recently, and with advent of NPs, thermogravimetric analysis (TGA) has also been used. In this investigation, asphaltenes uptake calculated from UV-Vis spectroscopy at three different wavelengths were compared with thermogravimetric analysis (TGA) results. Although the adsorption trends followed Langmuir isotherms, instrument as well as wavelength-dependent adsorption coefficients were obtained. TGA results are believed to be more reliable, provided complete oxidation and account of mass loss due to NPs is attained. UV-Vis measurements, on the other hand, may be impacted by the chemical structure of the asphaltenes sub fractions as well as their state of association. Al2O3 showed the highest adsorption capacity of 385 ± 5 mg/g, followed by Fe3O4 and Fe2O3. However, based on mg/m2, Fe2O3 displayed the highest adsorption capacity. TGA analysis revealed that the NPs promoted the oxidation of adsorbed asphaltenes in a reverse order to their adsorption capacity, qmax (mg/g) (Al2O3 > Fe2O3 ≈ Fe3O4). This trend is in line with a previous observation of mass-dependent thermo-oxidative profile and surface exposure role, rather than a catalyst role, of the NPs.
  • Thumbnail Image
    ItemOpen Access
    Geological Realization Rankings for Steam-Assisted Gravity Drainage (SAGD) Reservoir Dynamic Modeling
    (2018-12-11) Tamer, Mohamed Rajab; Chen, Zhangxin; Elmabrouk, Saber Kh; Dong, Mingzhe; Husein, Maen M.
    Geological realizations are generated using geological and petrophysical properties to capture the range of possible geologic variability presented in the reservoir under development. Reservoir dynamic modelling or reservoir simulation is typically conducted to identify the range of uncertainties in the geological realizations through fluid rates, volumes and recovery factors. Conducting dynamic SAGD reservoir simulation for all stochastic geological realizations for ranking is not viable in practice due to excessive amounts of computer time required especially when modelling a thermal process like SAGD. This thesis presents a novel approach that uses the geological realization characteristics including permeability, porosity, initial water saturation and block volumes to rank equal probable SAGD geological realizations in order to classify high, medium, and low performing SAGD realizations prior to SAGD simulation. This research work introduces five statistical averaging techniques, and then examines the coefficient of determination between the five statistical averaging ranking measures and the SAGD reservoir performance forecast of the SAGD geological realizations. These techniques encompass Permeability Mean (PM), Permeability Harmonic Mean (PHM), Block-Volume Permeability Harmonic Mean (BVPHM), Pore-Volume Permeability Harmonic Mean (PVPHM), and Bitumen-In Place Volume Permeability Harmonic Mean (BIPVPHM). To validate the five statistical ranking measures, nine generic SAGD realizations involving a shale slab of two different model grid dimensions and a number of seventy SAGD geostatistical realizations are examined. This research work also investigates ranking the SAGD geological realizations throughout the life of SAGD operations by comparing the coefficient of the determination between the ranking results and performance of SAGD geological realizations over 10 years of SAGD operations. The results indicate that the PM ranking technique can be used to explain the forecast of the SAGD performance of the generic geological realizations at early SAGD time up to 81% at most, whereas the PVPHM ranking technique can be used to explain the SAGD performance of the tested SAGD geostatistical geological realizations up to 74% at most. The introduced techniques can be included in a commercial dynamic reservoir package to re-process SAGD geostatistical geological realizations prior to conducting SAGD reservoir simulation studies on a selected group of the SAGD geological realizations for further reservoir simulation rankings.
  • Thumbnail Image
    ItemOpen Access
    The Impact of Surface Modified Nanoparticles on the Performance of Polymer Solutions for Heavy Oil Recovery
    (2019-08-13) Corredor Rojas, Laura Milena; Maini, B. B.; Husein, Maen M.; Sarma, Helmanta Kumar; Jalel, Azaiez
    The use of polymer flooding as an enhanced oil recovery (EOR) method to achieve a more uniform volumetric sweep of the reservoir has increased over the past ten years. However, chemical, thermal and mechanical degradation of the polymers reduce their viscosity, which affects their performance. Nanoparticles (NPs) have been proposed as additives to make polymer flooding economical in challenging reservoirs or harsh conditions. NPs in polymer solutions (nanopolymer sols) are, nevertheless, an emerging class of materials. A more structured approach is needed to properly understand the physical and chemical interactions between the NPs and the polymer solutions. In the first stage of this study, nanopolymer sols were prepared by adding silicon oxide (SiO2), aluminium oxide (Al2O3), and titanium oxide (TiO2) NPs, and in-situ prepared iron hydroxide (Fe(OH)3) NPs to polymer solutions of partially hydrolyzed polyacrylamide (HPAM) and xanthan gum (XG). In the second stage, the surface of the NPs were modified by chemical grafting with carboxylic acids, silanes, and polyacrylamide. The modified NPs were characterized using transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and energy-dispersive X-ray spectroscopy (EDX). All prepared nanopolymer sols were evaluated to determine their effectiveness in improving heavy oil recovery by studying their rheological properties at different shear rates and NP concentrations, colloidal stability, interfacial tension (IFT), and contact angle. Finally, a selected set of nanopolymer sols were evaluated by conducting oil recovery tests in a Hele-Shaw cell and linear sand-packs. According to the observations in Hele-Shaw cell, the fingering patterns of XG and XG/1.0-2.0wt% of NPs were characterized by the formation of branched structures (at earlier growth stage) which by merging and coalescing formed stable interfaces. However, HPAM and HPAM/1.0-2.0wt% of NPs exhibited different fingering patterns with tip-splitting or suppressed tip-splitting and side-branching. Only XG polymer solutions, modified with 1.0 and 2.0 wt.% of unmodified NPs improved areal sweep efficiency between 5 - 7%. For the displacements in the linear sand-pack, the NP concentration was reduced from 1.0 wt.% to 0.2 wt.% to improve the transport of the NPs into the porous media. The incorporation of 0.2 wt.% of unmodified and modified SiO2 NPs increased the viscosity of the XG solution at all salinities, whereas the high XG adsorption onto the surface of the Fe(OH)3, Al2O3, and TiO2 NPs reduced the viscosity. Adsorption of the NPs, SDS molecules, NP-SDS complexes and NP-polymer-SDS complexes onto the oil-nanofluid interface reduced the IFT of the XG solutions. Also, the NPs changed the wettability of the glass from oil-wet to intermediate-wet. The NPs increased the cumulative oil recovery of the salt-free XG solution between 3 and 9%. At 1.0 wt% NaCl, the NPs reduced oil recovery by XG solution between 5-12%, except for Fe(OH)3 and TiO2 NPs. These NPs increased the oil recovery between 2-3% by virtue of reduced polymer adsorption caused by the alkalinity of these nanopolymer sols. Additionally, the surface properties of SiO2, TiO2 and Al2O3 NPs were improved by polymer grafting. The HPAM nanopolymer sols exhibited lower IFT and ability to alter the wettability of the glass substrate from oil-wet to intermediate-wet. The thickening behavior of the HPAM solution was improved by the addition of 0.2 and 0.4 wt % TiO2-PAM NPs at all salinities. The displacement experiments demonstrated that the addition of TiO2-PAM NPs increased the cumulative oil recovery by 2% while the addition of SiO2-PAM and Al2O3-PAM NPs reduced it between 3 and 7% at 1.0 wt.% NaCl. At higher concentration, TiO2-PAM NPs can enhance oil recovery between 5 and 7%, independent of the salinity. It was also observed that the surface modified SiO2 NPs with silanes and carboxylic acids cannot improve the performance of the HPAM solutions. To conclude, the HPAM/TiO2-PAM, the XG/Fe(OH)3 and XG/TiO2 nanopolymer sols exhibited the best performance in displacing viscous oil in the linear sand-pack tests. The original contributions to knowledge from this research are 1) development of new polymer nanohybrids which enhanced heavy oil recovery, 2) formulation of new synthesis routes for polymer nanohybrids which improved the dispersivity of the NPs into the polymer solutions and the resistance of the polymer solutions to salinity and temperature, and 3) better understanding of the mechanisms contributing to the success of nanohybrids in chemical flooding.
  • Thumbnail Image
    ItemOpen Access
    Microstructure and flow behavior of cellulose nanocrystal stabilized emulsions with repulsive and attractive interactions
    (2018-12-17) Pandey, Aseem; Trifkovic, Milana; Bryant, Steven L.; Husein, Maen M.; Kantzas, Apostolos
    Surface properties of nanoparticles have a direct effect on the microstructure and rheological properties of the emulsions. In this thesis, I have utilized oscillatory shear rheology in conjunction with confocal microscopy and Cryo-SEM to understand the role of surface charge of Cellulose nanocrystal (CNCs) on the microstructure and rheology of dodecane in water emulsions. These fundamental understandings were applied to demonstrate the applicability of CNC stabilized emulsions as a conformance control agent through sandpack experiments. CNCs are a promising class of renewable nanomaterial with a rod-shaped morphology and negatively charged sulfate ester groups on the surface. Two different desulfation approaches were employed to modulate the surface charge of the CNCs. CNCs desulfated with hydrochloric acid (a-CNCs) were highly aggregated in water and shown to adsorb faster to the oil-water interface, yielding emulsions with smaller droplets sizes and a thicker CNC interfacial layer. CNCs desulfated using sodium hydroxide (b-CNCs) stabilized larger emulsion droplets and had a higher amount of non-adsorbed CNCs in the water phase. Rheological measurements showed that emulsions stabilized by a-CNCs formed a stronger network than for b-CNC stabilized emulsions due to increased van der Waals and H-bonding interactions that were not impeded by electrostatic repulsion. Based on these observations the conformance control performance and plugging efficiency of a-CNC stabilized emulsions through sandpack flow experiments was tested. The injected emulsions were aged inside the porous media for one day to develop a strong droplet network. The aged emulsions showed a promising selective phase blocking behavior with a very large pressure gradient required for water to flow as compared to dodecane. This selective phase blocking behavior can be specifically useful for near wellbore water shut-off treatment. The results of this investigation demonstrate the unique interactions between nanoparticles surface charge and the resulting emulsion properties which showed an interesting selective phase blocking behavior in porous media.
  • Thumbnail Image
    ItemOpen Access
    Modeling of Non-Equilibrium Interphase Mass Transfer during Solvent-Aided Thermal Recovery Processes
    (2018-09-14) Al-Gawfi, Abdullah; Hassanzadeh, Hassan; Abedi, Jalal; Sarma, Helmanta Kumar; Husein, Maen M.
    As most of the heavy oil reserves in the world are too viscous to be exploited conventionally, enhanced oil recovery (EOR) methods are applied mainly through utilizing heat or dilution. Two thermal recovery methods stand out to be the most viable and commercially practical for exploiting extra-heavy and highly-viscous oil reservoirs are Steam-Assisted Gravity Drainage (SAGD), and Cyclic Steam Stimulation (CSS) processes. Both processes apply heat to the reservoir using steam to reduce the viscosity of the bitumen rendering it mobile. Despite the commercial success of these thermal recovery processes, solvent-aided thermal recovery processes recently gained increased industrial interest for their potential to achieve higher energy efficiency, reduced environmental impact, and increased economic viability. In solvent-aided thermal processes, solvent is co-injected with steam to further aid in reducing bitumen viscosity through mass and heat transfer and diffusion of solvent into bitumen. Several field trials of solvent-based recovery processes have been carried out and field results were mixed or inconclusive, and that can be attributed to the lack of knowledge of the physics and inter-related mechanisms involved with interphase-mass transfer and solvent dissolution into bitumen. The first part of this thesis aims to address the mechanisms of solvent dissolution into bitumen due to solvent diffusion and defines the key parameter of diffusive dominant interphase-mass transfer coefficient for several solvent/bitumen binary mixtures. The results show that the diffusion of lighter solvents into bitumen is lower than heavier solvents particularly at low temperatures. Also, it was found that the diffusion dominant interphase-mass transfer coefficient is relatively higher for lighter solvents such as methane, ethane, and propane. Therefore, modelling of the non-equilibrium interphase-mass transfer phenomena is relatively more important for lighter solvents for designing and implementing a successful solvent-aided thermal recovery process. One of the most important mechanisms involved in solvent-aided thermal recovery processes is interphase-mass transfer phenomena which involves a variation of a system property due to a non-equilibrium state. However, in current reservoir simulation models a local equilibrium is assumed such that a simulation grid block is at instantaneous equilibrium. In reality, local equilibrium assumption often fails at larger scales or in situations where flow velocities are large compared to that of mass or heat transfer. In the second part of this thesis, solvent-aided gravity drainage of bitumen was simulated with propane as a solvent using CMG-STARS. The effect of non-equilibrium mass transfer was included in the model to simulate the process using a kinetic approach. The results show that the assumption of the local instantaneous equilibrium result in 3% to 6% lower oil recovery for the typical field scale simulation models. This difference in oil recovery can be mitigated fairly through the inclusion of the non-equilibrium interphase-mass transfer. Correlations for the non-equilibrium interphase-mass transfer coefficients for propane/bitumen mixture were developed which can be used as guidelines for modelling the non-equilibrium interphase-mass transfer for field scale simulations of solvent-based EOR processes.
  • Thumbnail Image
    ItemOpen Access
    Molecular Design of Solid Sorbents for Gas Capture Applications
    (2018-04-30) Bladek, Kamila Julia; Shimizu, George K. H.; Thangadurai, Venkataraman; Birss, Viola I.; Husein, Maen M.; MacLachlan, Mark J.
    Designing new solid sorbents can be difficult as many factors need to be considered if a better material is to be synthesized. Gas capture applications require not only a high uptake of a specific gas, but also high stability, high selectivity, and good mechanical properties. Creating coordination polymers that contain phosphonate ligands can add stability to the framework due to the strength of the metal-ligand bond., but there are many challenges with phosphonates, like the unpredictability, low crystallinity and preference for layered materials, that need to be overcome to make sorbents. The first metal-organic framework (MOF) synthesized used pyrene-1,3,6,8-tetraphosphonic acid with Cr3+, but it was synthesized using a hydrogen-bonded intermediate to overcome crystallinity issues. It had a surface area of 695 m2/g and a selectivity for CO2 over N2 of 319.5. It’s low regeneration energy and chemical stability make it interesting as a flue gas capture material. The next MOF was synthesized using Zr4+ and 1,3,5,7-tetrakis(4-phosphonophenyl)adamantane to increase stability and prevent a dense framework. The MOF had a surface area of 541 m2/g with a stability to acid. The water sorption was high at 14.5 mmol/g, making the material interesting for water adsorption processes. The last sorbents studied focused on the morphological control when using fluorene-2,7-diphosphonic acid versus the monoester, fluorene-2,7-diphosphonate bis(monoethyl ester). While studies with Co2+ showed sphere formation with the monoester, porosity and remarkable mechanical properties, the Ni2+ coordination polymer formed hollow spheres with a surface area of ~1200 m2/g. All of the materials synthesized illustrate how understanding of supramolecular concepts allow for the manipulation and improvement of properties of the desired sorbents. The thesis concludes with a discussion of the opportunities that exist in the area of solid sorbents and the future outlook of these materials.
  • Thumbnail Image
    ItemOpen Access
    Natural Gas Foam Stabilization by a Mixture of Oppositely Charged Nanoparticle and Surfactant and the Underlying Mechanisms
    (2018-08-29) Doroudian Rad, Mina; Dong, Mingzhe; Bryant, Steven L.; Husein, Maen M.; Lu, Qingye
    This study investigates the adsorption of sodium fatty alcohol polyoxyethylene ether sulfate surfactant (AES) on oppositely charged alumina-coated silica nanoparticle (SNOWTEX-AK), then the influence of surfactant and nanoparticle concentration on the stability of methane foam is described. It is found that the affinity of nanoparticle for the gas-liquid interface is strongly affected by the adsorption of surfactant on the surface of nanoparticles. Five adsorption stages, which are described in terms of the extent and type of surfactant coverage of the nanoparticles, explain the behavior of the solution at different surfactant/nanoparticle ratios. The most stable foam was found at small surfactant/nanoparticle ratios, at which the particles are partially covered with surfactants and have smaller aggregate size. For the surfactant concentration around CMC, the foam half-life at this synergistic concentration ratio range was found at least two times more than that of the foam stabilized solely by surfactants. The findings from this study provide a better understanding of the interaction between oppositely charged nanoparticle/surfactant pairs and how that interaction affects the foam stability.
  • Thumbnail Image
    ItemOpen Access
    The Role of Graphene Oxide - Polyacrylamide Interactions on the Stability and Microstructure of Oil-in-Water Emulsions
    (2018-08) Jahandideh, Heidi; Trifkovic, Milana; Bryant, Steven L.; Ponnurangam, Sathish; Husein, Maen M.
    The emulsification of oil in water by nanoparticles (NPs) can be facilitated by addition of costabilizers, such as polymers and surfactants. However, the mechanism of this synergistic effect and its impacts on emulsions’ properties remain unclear. In my thesis project, I have studied the synergistic interaction of NP-polymer systems using graphene oxide (GO) and an anionic polyacrylamide (PAM) in stabilization of paraffin oil/water emulsion systems. Oil-free GO and GO-PAM dispersions were analyzed by imaging their morphology directly via Cryo-TEM and atomic force microscopy (AFM). X-ray diffraction (XRD) results confirm the adsorption of PAM molecules onto GO sheets resulting in the formation of ultimate GO-PAM complexes. The adsorption phenomenon is a consequence of hydrogen bonding and acid-base interactions, conceivably leading to a resilient hybrid electron-donor-acceptor complex. The microstructures of emulsions that are captured with two-color fluorescent microscopy and Cryo-TEM reveal the localization of GO-PAM complexes at the interface while large GO-PAM flocs coexist at the interface and in between oil droplets. Rheological measurements confirm that GO-PAM complexes have a higher desorption energy from the interface. Our findings, with insights into both structure and rheology, form a foundational understanding for integration of other polymers and NPs in emulsion systems, which enables efficient design of these systems for an application of interest.
  • Thumbnail Image
    ItemOpen Access
    Upgrading of residues in non-catalytic and slurry-type catalytic batch reactors
    (2019-04-30) Kaminski, Thomas; Husein, Maen M.; Hill, Josephine M.; Yarranton, Harvey W.
    As the demand for petroleum products is steadily increasing, heavy oils are playing a bigger role in providing the supply required to meet the demand. However, heavy, unconventional crudes need to first be upgraded to more useful light fractions. While upgrading has a deep history with extensive literature, the goal of this work is to investigate the use of several novel catalysts and process configurations to enhance upgrading of residue fractions. In this work, upgrading of various residue feedstocks via thermal cracking and hydrocracking was performed in an autoclave. The overall objective was to maximize the liquid fraction and quality in terms of viscosity and °API gravity. A variety of techniques such as gas chromatography (GC) were employed to provide more insight to results. The following topics were addressed in the thesis: effect of morphology on the hydrocracking performance of a zeolite-based catalyst, the hydrocracking performance of a novel Ni-Mo supported drill cuttings catalyst, an investigation into the potential removal of the vacuum distillation unit in a typical oil refinery, and a kinetic modelling of atmospheric and vacuum residues to determine the effect of maltene composition on the kinetics of the thermal cracking reactions. It was found that a fibre form zeolite catalyst performed better than a particle form, suggesting that morphology plays an important role during hydrocracking. Drill cuttings promoted in-house with Ni-Mo resulted in improved hydrocracking performance. A direct comparison between thermal cracking of Arabian atmospheric and vacuum residues showed an advantage of direct upgrading of atmospheric residue over the traditional use of a vacuum distillation unit followed by upgrading. Use of an AR-derived kinetic model to predict experimental data from catalytic thermal cracking of VR resulted in significant error, suggesting that composition of the liquid fraction plays an important role in the kinetics of catalytic thermal cracking.