Browsing by Author "Husein, Maen"
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- ItemOpen AccessA (w/o) microemulsion approach for in-situ preparation of high concentrations of colloidal metal oxide nanoparticles(2007) Nassar, Nashaat; Husein, MaenControl over nanopa1ticle size 1s a key factor which labels a given nanoparticle preparation technique successful. When organic reactions are mediated by ultradispersed catalysts the concentration of the colloidal nanocatalysts and their stability become key factors as well. Ultradispersed metal oxide nanoparticles have applications as heterogeneous catalysts for organic reactions, and were recently demonstrated as effective H2S(gl absorbents. The catalytic activity and absorption effectiveness of metal oxide nanoparticles depend primarily on their surface area, which in turn, is dictated by their size, colloidal concentration and stability. This work presents a water-in-oil (w/o) microemulsion approach for in-situ preparation of ultradispersed metal oxide/hydroxide nanoparticles, namely: iron and copper and discusses the effect of different (w/o) microemulsion variables on their stability and highest possible time-invariant colloidal concentration (nanoparticle uptake). The concentration of the stabilized metal oxides corresponded to the nanoparticle uptake. In-situ preparation of colloidal catalysts and absorbents minimizes aggregation associated with storage and transportation. Much higher surface area per unit mass of nanoparticles and per unit volume of the colloidal suspension than reported in the literature was obtained. The following trends in the colloidal concentration were common for the (w/o) microemulsion system and the heavy oil matrix. An optimum water to surfactant mole ratio, R, was found for which a maximum nanoparticle uptake was obtained. Nanoparticle uptake increased linearly with the surfactant concentration and displayed a power function with the precursor salt concentration. A mathematical model based on correlations for water uptake by Winsor type II microemulsions accurately accounted for the effect of the aforementioned variables on the nanoparticle uptake by the microemulsions. Furthermore, the in-situ microemulsion approach developed in the first part was applied for in-situ preparation of effective H2Scgl colloidal absorbents within heavy oil matrix. H2 Scgl is a by-product of insitu heavy oil upgrading with potential negative impact on underground water. In this work, preliminarily evaluations of the effectiveness of the in-situ prepared colloidal iron oxide/hydroxide in heavy oil matrix for the absorption of H2 S(gJ was conducted successfully.
- ItemOpen AccessA Field Application of Nanoparticles For Improved Downhole Losses in Invert Emulsion Drilling Fluids(2015-05-25) Borisov, Alexey; Husein, Maen; Hareland, GeirInvasion of drilling fluids filtrate and solids into porous, permeable, fractured or vuggy zones can cause formation damage and presents a major source of drilling problems. Furthermore, downhole mud losses also increase environmental and financial risks associated with drilling operations, costing over $1B annually. This thesis investigates the use of in situ prepared calcium carbonate nanoparticles (CNP) for fluid loss prevention in invert emulsion drilling fluids. CNP at 5 wt% concentration were synthesized within a custom ‘carrier’ emulsion using a modified microemulsion approach. Subsequently, the carrier emulsion was used to deliver target concentration of NPs to a host drilling fluid of interest via volumetric dilution. High pressure, high temperature (HPHT) fluid loss experiments on commercial invert emulsion drilling fluids showed that CNP at concentration of 0.5 wt% provided a 20–50% improvement over conventional lost circulation materials (LCM). In addition, basic properties of mud samples were not affected significantly in the presence of the carrier emulsion. In order to evaluate performance of CNP under real-life conditions, six full-scale field tests were conducted in horizontal wells in Alberta, Canada. Industry-scale synthesis of CNP followed the lab-bench process and was implemented at a specialized mixing facility. The results suggested that the scale-up from 3×10-4 m3 (300 mL) to 20 m3 did not affect average particle size or final properties of the carrier emulsion. Furthermore, field HPHT data showed good agreement with the lab experiments, where the average fluid loss in the test wells was reduced by 20–30% compared to the control wells using conventional drilling fluids. Finally, analysis of mud losses revealed that the cumulative losses while drilling were on average 20–30% lower in the presence of 0.5 wt% CNP, which suggested that NPs help to reduce downhole losses.
- ItemOpen AccessA method for converting aqueous demetallization products into dispersed metal oxide nanocatalysts in heavy oil(2012) Abdrabo, Amr Abdelrazek Elgeuoshy Meghawry; Husein, MaenMetallic heteroatoms deactivate expensive catalyst and, thus, should be removed at early stages during crude oil processing. Electro and biological demetallization are examples of two emerging techniques which remove the metallic heteroatoms; mainly nickel and vanadium, into ions or ionic complexes ultimately residing in the aqueous phase of a two phase water/oil system. This work investigates the conversion of the aqueous metallic species into metal oxide nanoparticles, which are effective upgrading catalysts, dispersed in the oil phase. The conversion step commenced in-situ within a water-in-oil emulsion structure, and the resultant nanoparticles remain very well dispersed in the heavy oil phase. The product nanoparticles were characterized, after successful collection from the oil phase, using X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy dispersive X-Ray spectroscopy (EDX). Despite the complexity of the heavy oil system, results confirmed the in-situ formation of NiO and V2 05 nanoparticles with mean sizes of 20 and 15 nm, respectively. Some aggregates have, nevertheless, formed, due to the relatively high temperature requirement of the method. Investigating the catalytic role of the as-prepared nanoparticles was limited to the NiO nanoparticles, since only low concentrations of V20s could be prepared. An attempt to increase the concentration of dispersed V2 05 by using precursors with higher solubility in water was not successful. A semi-batch reactor setup was employed to investigate the catalytic hydrocracking of heavy oil in the presence of dispersed NiO nanoparticles. On the other hand, batch reactor arrangement was employed to study the thermalcracking of heavy oil in the presence of dispersed NiO nanoparticles.
- ItemOpen AccessAdsorption and Oxidation of Asphaltenes onto in situ Prepared and Commercial Nanoparticles(2014-01-29) Abu Tarboush, Belal; Husein, MaenAbstract Removal of asphaltenes from heavy oil improves the quality of oil and makes it easier to process. In the current work, in situ prepared NiO and Fe2O3 nanoparticles within heavy oil, display much higher affinity towards asphaltenes adsorption than commercial ones. Nanoparticle preparation followed a method developed by our group and XRD, EDX and TEM analyses confirmed the formation of NiO nanoparticles of 125 nm and Fe2O3 nanoparticles of 36±5 nm mean diameter. Kinetic experiments showed that, while equilibrium could be achieved in less than 2 h for both in-situ prepared and commercial NiO particles, much higher adsorption took place onto the in-situ prepared ones, owing to their better dispersion. An uptake in the order of 2.8 and 2.7 g asphaltenes/g nanoparticles was reported for in-situ prepared NiO and Fe2O3 nanoparticles, respectively. Commercial NiO and Fe2O3 nanoparticles of the same size range and subject to the same experimental conditions only adsorbed 15% and 25% of the above values, respectively. Degassing temperature was found to have a major effect on the surface area. For in situ prepared Fe2O3, surface area evaluated by BET method following degassing the sample at 200oC was found to be significantly lower than the one evaluated at 300oC. SEM analysis for non-heat treated and heat treated, at 300°C, in-situ prepared Fe2O3 showed that heat treatment caused more resolution and provided more definition of the capped nanoparticles with the agglomerated cluster. The difference between the heat treated and non-heat treated samples supports the adsorption model in which hydrocarbons were adsorbed onto the nanoparticles and not vice versa. Monolayer adsorption on the nanoparticles was reported from the toluene model solutions. Contrary to literature findings on adsorption from model solutions onto nanoparticles, our results support a model of sequential oxidation of adsorbed asphaltenes and multilayer adsorption of asphaltenes from heavy oils onto in-situ prepared and commercial NiO nanoparticles. The thermal behavior of the multilayered asphaltenes suggests new interpretation of the role of the nanoparticles.
- ItemOpen AccessAdsorption of heavy hydrocarbons for the purpose of hydrogen production(2008) Sosa, Clementina; Moore, R. Gordon; Husein, Maen
- ItemEmbargoApplication of Nanoparticles in Regular and Foamed Cement-Based Systems(2024-01-19) Mehairi, Ahmed; Husein, Maen; Khoshnazar, Rahil; Aguilera, Roberto; Chen, Shengnan (Nancy); Hassanzadeh, Hassan; Torabi, FarshidNano-modification of cement-based materials (CBMs) has the potential to enhance the mechanical properties of conventional CBMs and provide sustainable and energy-efficient solutions to mitigate the environmental footprint of cement manufacturing. Over the past years, the addition of nanoparticles (NPs) into cement paste, mortar, and concrete has shown outstanding enhancements in their mechanical properties and durability. Large-scale application of NPs in CBMs still, however, faces challenges such as improper dispersion, poor economics due to the cost of NPs, and potential health concerns associated with NPs handling. This work attempts to tackle these barriers by proposing inexpensive methods of NPs incorporation into oil well cement slurry and foamed concrete (FC). For oil well cement slurry, an easily scalable approach of NPs synthesis during cement slurry mixing is developed. Three methods for preparing in situ Fe(OH)3 NPs are presented. At 0.7 wt% of dry oil well cement, in situ prepared Fe(OH)3 NPs increases the 1-day compressive strength of the cement slurry by up to 90% and 38% at 25 oC and 80 oC, respectively, outperforming commercial NPs. Significant reductions in porosity (up to 48%) and permeability (up to 93%) are also achieved. Moreover, cement slurries with Fe(OH)3 NPs exhibit high resistance to fatigue from repeated compression cycles. In addition to oil well cement slurry, incorporation of NPs into FC through NP-stabilized preformed foams has been shown to overcome major FC drawbacks such as slurry instability and poor durability. In this study, the formulation of a stable in-house CaCO3 NPs/ hexadecyltrimethylammonium bromide (CTAB) dispersion is achieved. In the presence of pure N2 and a 2:1 CO2/N2 gas mixture, foams produced from this dispersion have half-lives of 5 – 6 h compared to 5 – 7 mins for CTAB alone. The presence of CaCO3 NPs also reduces the average bubble size by 67% and enhances foam thermal stability. The utilization of CaCO3 NPs/CTAB aqueous foam in FC improves slurry stability and leads to a narrower and more uniform pore size distribution than FC made with CTAB alone. CaCO3 NPs also accelerate the formation of hydration products and promote the formation of a denser solid matrix. These combined effects contribute to a less connected pore structure, reduction in atmospheric carbonation, and improved heat transfer and fire resistance properties.
- ItemOpen AccessBond Strength of Adhered Manufactured Thin Stone/Brick Masonry Veneer Units to Setting Bed Mortar at Different Temperatures and Different Cycles of Freeze-Thaw(2021-05-14) Rizaee, Samira; Shrive, Nigel; Duncan, Neil; Khoshnazar, Rahil; Husein, Maen; Feldman, LisaClose to no study has been conducted to identify the possible influential physical and mechanical characteristics of adhered thin masonry units and mortars on the bond strength in adhered thin masonry veneer (ATMV) applications. There have been numerous cases of bond failures in ATMV applications probably due to lack of knowledge and the lack of any standards for the design and installation of ATMV. In the Canadian climate, exposure to extreme weather conditions like very low temperatures and freeze-thaw cycles are common and may be a cause of bond deterioration and failures. Therefore, it is important to study the effects of exposure to extreme weather conditions on the bond strength. This research first measures and evaluates the physical and mechanical properties of thin masonry units and mortars. Then shear and tensile bond strengths are studied considering different age and environmental factors. At least three different ages, two different curing temperatures, three testing temperatures and four cycles of freeze-thaw were considered. Subsequently, any possible relationship between these characteristics and bond strengths were evaluated and proper practices were recommended.
- ItemOpen AccessDevelopment of Phosphoryl-Bridged Viologens Toward Functional Materials(2017) Stolar, Monika; Baumgartner, Thomas; Piers, Warren E.; Roesler, Roland; Husein, Maen; Morin, Jean-FrancoisThe work in this thesis provides a new class of viologen-based materials, phosphoryl-bridged viologens, for applications in organic electronics. Each chapter focuses on the properties of the materials and their applicability to a specific application. In addition, the chapters build upon the synthesis and properties of each other leading to a better understanding of phosphoryl-bridged viologens and more sophisticated applications. Chapter Two utilized the beautiful electrochromic character of phosphoryl-bridged viologens for application in electrochromic devices. Successful functionalization with various benzyl-substituents led to modification of the reduction potential but preserved the colour of the species, leading to a proof-of-concept electrochromic device. Chapter Three built upon the synthesis from the previous chapter, expanding a library of monomer to a library including dimers and main-chain polymers with the phosphoryl-bridged viologen core. The materials discussed in this chapter resulted in hybrid organic/Li- ion battery half-cells with the potential application for fully organic batteries. While phosphoryl-bridged viologens are not the current front-runners in this field, they offer a unique property that allows for increased charge to mass ratios for a higher energy density material. In addition, the phosphoryl-bridged viologen utilized offer exceptionally charging/discharging stability, which is a current pitfall of Li-ion batteries. Chapter Four developed new functionalizations of phosphoryl-bridged viologens for anchoring onto inorganic nanoparticles or immobilized substrates increasing the utility of this family of materials. Phosphoryl-bridged viologens proved to be excellent electron-acceptors of photoexcited titanium dioxide electrons for potential applications in photocatalysis. In addition, this chapter features the stable methyl viologen and phosphoryl-bridged viologen radicals in water, where their brilliant colour is preserved over several hours. Finally this thesis concludes with an immediate outlook on these materials and their potential success in organic electronics. The goal of this thesis was to establish a new library of phosphoryl-bridged viologens and demonstrate preliminary applications as organic electronic materials.
- ItemOpen AccessDynamic Characterization of Naturally Fractured Reservoirs with Fractal Geometry: Methodology of Analysis(2016) Vargas, Lauro; Chen, Zhangxing (John); Husein, Maen; Wu, Yu-ShuNaturally Fractured Reservoirs (NFR) contain over 60% of hydrocarbon reserves in the world. Most NFR have heterogeneities occurring in a wide range of spatial scales. Generally, NFR are modeled using Euclidean geometry with homogeneous fracture systems that work well for some specific cases. However, the presence of fractures at different scales, the non-uniform distribution of fractures, and the connectivity of the fracture network are important factors of uncertainty in reservoir models. Fractal geometry is one of the best ways to take into account heterogeneities present in a porous medium at different scales, their non-uniform distribution in space, and the connectivity of the fracture network. This thesis puts forward a methodology to identify, validate and define the fractal parameters from NFR. It considers reservoir engineering and geologic information to gain a comprehensive understanding of this type of reservoirs. This methodology was applied to two field cases from the southwest of Mexico.
- ItemOpen AccessEffect of alternative crosslinking agents on the thermo-rheological properties of SBS-modified asphalts(2023-12-22) Perez Jaimes, Juan Sebastian; Jasso, Martin; Khoshnazar, Rahil; Husein, MaenCurrent industrial practices rely on the modification of asphalt by thermoplastic elastomers, particularly styrene-butadiene-styrene, crosslinked with a small amount of sulfur. This technology allows the formation of a three-dimensional polymer network with a significant impact on thermo-rheological and engineering properties. However, gelation of the material and potential development of harmful sulfur emissions may occur. This work concentrates on the mechanism of modification and development of thermo-rheological properties of styrene-butadiene-styrene modified asphalt crosslinked by novel sulfur-based and sulfur-free crosslinkers. The properties of crosslinked modified asphalts were studied by Superpave binder specification tests and rheological tests conducted in the linear and non-linear viscoelastic region. The results were compared with currently used crosslinking technology employing elemental sulfur as well as with the technology without any crosslinking agent. The results from Superpave binder specification showed that the samples crosslinked with novel sulfur-based crosslinking agents were less sensitive to thermo-oxidative degradation than the sample crosslinked with elemental sulfur. This behavior was confirmed by the thermogravimetric analysis which also provided insights about decomposition and combustion behavior. In addition, modified asphalts crosslinked with sulfur and sulfur-based crosslinkers had the highest values of %Recovery_3.2kPa. The appearance of the “shoulder” on the master curves of G'(ω) and the local maximum followed by the local minimum on the master curves of tanδ(ω) suggested exceptional resistance of modified asphalts crosslinked by sulfur and sulfur-based crosslinkers to deformation. The development and strength of polymer network were evaluated by the presence of viscosity overshoots and stress overshoots in the steady-state viscosity and start-up of steady shear measurements, respectively. The effects of crosslinking technologies were also evaluated via mechanical glass transition temperature and modulated differential scanning calorimetry. Obtained results point to a considerable difference in the crosslinking mechanism which was also reflected by significant differences in morphology of prepared modified asphalts at ambient temperature. Although sulfur and sulfur-based crosslinking systems had superior performance, the non-sulfur-based crosslinking systems could play a significant role in the reduction of odor and sulfur emissions in densely populated areas.
- ItemOpen AccessElectrochemical behavior study towards demetallization and selective separation of vanadyl oxide tetraphenyl porphyrin from heavy oil(2012) Ouled Ameur, Zied; Husein, MaenVanadium is one of the most troublesome heavy metals present in the asphaltenic portion of oil sands deposits, mainly in the form of metalloporphyrins. These metal complexes can easily lead to the deactivation of desulfurization and cracking catalysts during the hydrotreatment and hydrocracking refining processes as well as the emission of vanadium pentoxide during combustion in stacks downstream. The problem is more pronounced for the Alberta heavy oil and oil sands producers, since bitumen contains much higher concentrations of vanadium than conventional crude. The first part of the thesis explores a way of improving the electrochemical redox reactions by introducing dispersed nickel nanoparticles. The electrochemical behavior of the well know probe potassium ferricyanide (PFC) is monitored in aqueous and (w/o) microemulsion systems. The electrochemical behavior of PFC in aqueous solutions is well documented in the literature, while (w/o) microemulsion systems are good heavy oil model solutions. Observations and interpretations made on the PFC behavior are extended to the study of the removal of a model vanadyl compound, vanadyl oxide tetraphenyl porphyrin (VOTPP), from heavy oil model systems. In presence of dichloromethane and tetrabuhtylammonium perchlorate as a supporting electrolyte the cyclic voltammetry shows that VOTPP behaves quasi-reversibly. In heavy oil model solutiontype dichloromethane/HepTol, on the other hand, the cyclic voltammograms show an irreversible behavior as confirmed by the Randles-Sevcik plots. The second part of the thesis investigates, in details; an observation made during electrochemical demetallization of VOTPP, and led to selective removal of VOTPP from heavy oil in tetrahydrofuran (THF) and methanol by salting-out as a result of stepwise addition of 1.0 M NaCl aqueous solution.
- ItemOpen AccessElectrocoagulation for the Treatment of Oilsands Tailings Water(2015-10-07) Panikulam, Paul; Roberts, Edward; Husein, MaenThe treatment of tailings water, a major environmental challenge facing the oil sands industry is explored in this research. The focus was on the removal of very fine solids, a very difficult to treat contaminant in tailings water. Electrocoagulation, an electrochemical method of water treatment was tested to assess the performance in removal of fines. Synthetic wastewater samples with kaolin clay dispersed was used as a model. Different electrochemical reactor designs were tested to assess the contaminants removal performance. The results show that electrocoagulation is very effective at removal of fines. Turbidity removals of over 95 % were achieved in 20 minutes settling time versus a control experiment that achieved removals of only 10% for the same settling time.
- ItemOpen AccessExperimental Analysis and Mechanistic Modeling of Wellbore Strengthening(2012-10-04) Mostafavi Toroqi, Seyyed Vahidreza; Hareland, Geir; Aadnoy, Bernt; Husein, MaenWellbore strengthening refers to the science and technology of increasing the pressure level at which circulation loss to the formation occurs. Although a fairly wide range of technologies have been proposed and tested, the application of engineered drilling fluids has proven to be the most promising approach. Circulation loss, which is one of the most troublesome issues occurring in drilling operations, is experienced at varying levels of severity. It is most expected in highly permeable formations, fractures and caverns. Lost circulation may have several consequences including fluid inflow, wellbore collapse, formation damage, non-productive rig time and environmental contamination. In order to mitigate the risks of circulation loss, a broad range of treatments and preventive methods have been practiced such as application of Lost Circulation Materials (LCM), cement plugs, squeeze gunk, gels and technologies like aerated drilling and stress caging. It has been observed that lost circulation occurs at varying pressure levels dependent on drilling fluid properties. This observation builds the foundation for drilling fluid based wellbore strengthening. Wellbore strengthening has been described previously but a general model to take into account the effects of fluid properties and its constituents does not exist. In addition, the governing mechanisms of this process are not well understood and explained in the literature. In this study a comprehensive literature survey and an extensive experimental analysis was completed to determine the mechanism of and contributing factors to wellbore strengthening. Next, a mechanistic model was developed and verified to predict the formation resistance prior to allowing drilling fluid loss. A field case of wellbore strengthening was also studied where the developed model exhibited a very good agreement. Results from this research are mostly directed towards circulation loss prevention via tensile fractures. However, they might be applicable for pore scale seepage loss through gravels and natural fractures. In the first chapter, an introduction to the circulation loss issue and its consequences is presented. Chapter two is dedicated to a brief review on wellbore stability analysis and a thorough survey on wellbore strengthening. In chapter three, the experimental part of this research is explained and its results are discussed. In chapter four, the experimental results are applied to build a mechanistic model. The model is analyzed and verified using a field case of wellbore strengthening. Conclusions of this research and some recommendation for future studies are presented in Chapter five.
- ItemOpen AccessFundamental Understanding of Warm Lime Softening Process to Improve Steam Assisted Gravity Drainage Produced Water Treatment Performance(2021-01-15) Zhang, Lu; Lu, Qingye; Husein, Maen; Park, SimonSince the commercialization of the first steam assisted gravity drainage (SAGD) enhanced oil recovery facility in 2001, the warm lime softening (WLS) process has been commonly deployed as part of a SAGD central processing facility (CPF) water treatment plant. The principal process goal of the WLS process is to remove dissolved hardness (e.g. calcium and magnesium ions) and silica by the addition of lime (Ca(OH)2), magnesium oxide (MgO), soda ash (Na2CO3), coagulant, and flocculant. Although the WLS process has been operated for almost 30 years in the oil sands industry, the fundamental electrokinetic properties of the particles generated are not thoroughly investigated. The high temperature, high silica and dissolved organic concentrations also make the WLS unique compared to the traditional cold lime softening process used in municipal water treatment and other industrial water treatment. The understanding of the electrokinetic properties of particle suspensions is of paramount importance as it directly relates to the performance of sedimentation and clarification, as well as the selection of chemicals and doses. Furthermore, the understanding of the impact of feed water chemistry deviations on the charge behaviors of the particle suspensions and on the coagulant dose is of significant practical implications for the WLS operations. This research was undertaken to investigate the surface charges of the two most common softening particles, calcium carbonate (CaCO3) and magnesium hydroxide (Mg(OH)2), under SAGD WLS conditions from zeta potential perspective. A number of experimental conditions (pH, temperature, presence of other ions, additions of other chemicals) were varied to exam the impact on the zeta potential of two softening particles. Visual MINTEQ modelling was utilized to predict chemical speciation under various conditions and was used to assist with data interpretation. High temperature (65°C) jar tests were also performed using synthetic SAGD produced water (PW) samples to simulate the WLS process and assess the impact of feed water deviations (silica, clay, humic acid, Ca(OH)2, MgO, Na2CO3, NaHCO3, CaCl2, and MgCl2) on the dose of a polyamine-based cationic coagulant. The electrokinetic study revealed that pH, and the type of ions and functional groups present in solution are the main impacting factors on the zeta potential of softening particles. The coagulation study revealed that the coagulant dose was significantly influenced by humic acid and silica. The findings of this research can provide insightful knowledge to SAGD operators regarding process monitoring, approaches to onsite chemical optimization, possible controls during an influent water off-specification event.
- ItemOpen AccessImproved meuf treatment of produced water utilizing naphthenic acid co-contaminants(2009) Deriszadeh, Ali; Husein, Maen; Harding, Thomas
- ItemOpen AccessImproving Steam-Assisted Gravity Drainage using Conformance Control Agents: Oil-in-Water Emulsion and Steam Foam(2022-09-16) Chen, Zan; Husein, Maen; Bryant, Steven L; Dong, Mingzhe; Hassanzadeh, Hassan; Lu, Qingye; Nezhad, Amir S; Li, SongyanSteam-assisted gravity drainage (SAGD) is a commercially successful thermal recovery method for extracting bitumen in the deep oil sands reservoirs. Over the years, many modifications of the original SAGD process have been proposed to improve the performance, yet the results of these modifications remain unsatisfactory. In addition, the efficiency of SAGD is significantly impacted by the intrinsic heterogeneity of the oil sands reservoir. In this study, we investigate the feasibility of improving SAGD with conformance control agents; namely oil-in-water (O/W) emulsion and steam foam. We first studied the effect of oil phase viscosity on the plugging performance of O/W emulsion using sandpack flow test. A comprehensive experimental investigation was then conducted to understand the steam foam propagation and its potential for conformance control. In particular, the effect of liquid drainage on steam foam behavior in the porous media was studied. Finally, numerical investigation was carried out to evaluate FA-SAGD performance under different injection strategies and reservoir heterogeneities. Experimental results show that oil viscosity of O/W emulsion considerably affects its plugging ability. Frictional resistance increases as oil viscosity increases, but the rate of increment tapers down significantly. Stable steam foam can be generated in high permeability sandpacks, while the foam behind the moving foam front quickly coarsens in low permeability packs. The effect of liquid drainage is more significant when weak steam foam is present in the porous media. Successful profile control is achieved in parallel-sandpack flow tests and a detailed multi-cycle diversion of flow is identified. Simulation results further demonstrate that application of steam foam generally improves the energy efficiency and oil production of SAGD. For a homogeneous reservoir, slug injection when the steam chamber is fully developed yields the largest increment in oil recovery relative to SAGD. A 365-day foam slug injection results in 11.2% increment in oil recovery with satisfactory production rate. In contrast, early slug injection after preheating is recommended for heterogeneous reservoir with permeability variation in the horizontal direction. To conclude, O/W emulsion and steam foam can be applied at different stages of SAGD operation and both show great potential for improving SAGD performance.
- ItemOpen AccessIn-situ removal of H2S using ultradispersed iron oxide nanoparticles(2007) Patruyo, Luis Gerardo; Husein, Maen; Almao, Pedro R. Pereira
- ItemOpen AccessMachine Learning Methods for Kick Detection(2023-01-20) Abdul-Ameer, Haider; Shor, Roman; Hejazi, Hossein; Husein, Maen; Chen, Zhangxing; Butt, StephenEarly kick detection is crucial for a safe drilling operation while alarming kick events and helping to prevent blowouts. This research uses machine learning methods to develop data based kick detection models. OpenLab simulator used to create the Kick and NoKick class training and test data; the simulator drilling parameters used: Delta flow, Hook load, Pit volume, WOB (Weight On Bit), ROP (Rate Of Penetration), RPM, SPP (Standpipe Pressure) and Torque. This research selected the following machine learning algorithms: Decision Tree, Naive Bayes, Logistic Regressions and Neural Network. MATLAB was utilized for training and testing the different machine learning kick detection models. For each of these kick detection models, performance is calculated using precision (Kick classes truly predicted divided by the sum of kick classes truly predicted and Kick classes falsely predicted) and recall (Kick class truly predicted divided by the sum of kick classes truly predicted and NoKick classes falsely predicted) metrics. This research used a modified MATLAB radbas function as a reward function for the neural network model transfer functions to improve the model performance. Also, new model performance metrics were developed to evaluate the kick detection models in a more realistic way than precision and recall. These new metrics measure the models' ability to predict the kick event with an adequate early or late kick detection threshold time. MATLAB runs showed that decision tree and neural network are the most efficient models for detecting the kicks on the test data. Neural network and decision tree models' best accuracy showed an 85% KDP ( Kick Detection Performance) versus 54% for naïve bayes and 39% for logistic regression. These models' KDP were associated with the highest NPP (NoKick Prediction Performance) for both decision tree and logistic regression at 100% and naïve bayes at 92%, while neural network NPP was only 46%. A neural network model using the reward function detected 11 kicks out of the test data total of 13 kicks using a robust 10 second kick detection threshold time; this proves that the neural network model can detect the kick event quicker than the conventional kick detection systems.
- ItemOpen AccessNanoparticle-based Drilling Fluids with Improved Characteristics(2013-09-16) Zakaria, Mohammad Ferdous; Husein, Maen; Hareland, GeirThe success of well-drilling operations is heavily dependent on the drilling fluid. Drilling fluids cool down and lubricate the drill bit, remove cuttings, prevent formation damage, suspend cuttings and also cake off the permeable formation, thus retarding the passage of fluid into the formation. During the drilling through induced and natural fractures, huge drilling fluid losses lead to the higher operational expenses. That is why, it is vital to design the drilling fluid, so that it may minimize the mud invasion in to formation and prevent lost circulation. Typical micro or macro sized lost circulation materials (LCM) show limited success, especially in formations dominated by micro and nano pores, due to their relatively large sizes. The objective of this thesis was to investigate the performance improvement by the usage of NPs (nanoparticles) as lost circulation additives in the drilling fluid. In the current work, a new class of nanoparticles (NPs) based lost circulation materials has been developed. Two different approaches of NPs formation, and addition, to water based and invert-emulsion drilling fluid have been tested. All NPs were prepared in-house either within the invert-emulsion drilling fluid; in-situ, or within an aqueous phase; ex-situ, which was eventually blended with the drilling fluid. The laboratory measurements included measuring mud weight, pH, lubricity viscosity, gel strength, standard API LTLP filter test and high temperature and high pressure (HTHP) test. In this work we evaluated fluid loss performance of a wide range of NPs preferably selected from metal hydroxides, e.g. iron hydroxide, metal carbonates, e.g. calcium carbonate and metal sulfate and sulfide e.g barium sulphate and ferrous sulfide respectively. The use of improved NP-based invert emulsion drilling fluid showed an excellent fluid loss control, rheological properties together with a good lubricity profile. This thesis reports an experimental and theoretical study on filtration properties of invert emulsion drilling fluids under static conditions. Under API standard filtration test at LTLP and HTHP, more than 70% reduction in fluid loss was achieved in the presence of 1-5 wt% NPs. The results have also shown that the filter cake developed during the NP-based drilling fluid filtration was thin (thickness less than 1 mm), which implies high potential for reducing the differential pressure sticking problem, formation damage and torque and drag problems while drilling. Moreover, at the level of NPs added, no impact on drilling fluid apparent viscosity, and the fluid maintained its stability for more than 4 weeks. Other NPs prepared by in-situ and ex-situ method also showed an excellent fluid loss control. Results of the modeling showed that NP-based drilling fluid didn’t follow the Darcy equation at the initiation of filtration and therefore the initial region was found flat and nanoparticles reduced the premeability instantly. It was also shown that nanoparticles transport in filtration was predominantly influenced by the Brownian diffusion. Compare with the drilling fluid alone and drilling fluid with LCM, increasing shear rate did not increase the same extent of shear stress in case of NP-base fluid (both ex-situ and in-situ prepared), which can be attributed to the fact that smaller particles were dispersed more effectively than the larger bulk particles and provided bridging between clay particles due to their larger surface area. Tailor made NPs with specific characteristics is thus expected to play a promising role in solving the circulation loss and other technical challenges faced with commercial drilling fluid during oil and gas drilling operation.
- ItemRestrictedNanoparticle-mediated Heavy Oil Hydro and Thermal Cracking(2013-12-03) Alkhaldi, Salman Jarallah; Husein, MaenAbstract In this study, metallic nickel and alumina ultradispersed nanoparticles were prepared in-situ in heavy oil phases composed of vacuum residue, VR, and vacuum gas oil, VGO, by means of reduction or thermal decomposition of dispersed aqueous precursors of the metals. The catalytic activity of the nickel and the alumina nanoparticles towards hydrocracking and thermalcracking of the heavy oil was assessed. The thermal behavior of adsorbed materials onto the in-situ prepared as well as commercial Al2O3 nanoparticles was studied under an oxidizing atmosphere. Results suggested that commercial Al2O3 has more adsorption affinity towards hydrocarbons from the heavy oil. Accordingly, ultradispersed commercial Al2O3 nanoparticles were employed for the thermalcracking of an even heavier crude. Results show that the Ni0 was converted to Ni3S2 during the hydrocracking experiment. The catalyst promoted hydrogenation and free radical reactions and resulted in 50% reduction in asphaltenes and 70% reduction in resins, while improving the aromatics and saturates fractions. Two fold increase in the gaseous fraction and around 47% conversion of the residue, conv545+oC, occurred in the presence of the ultradispersed Ni catalyst. Alumina nanoparticles, on the other hand, contributed to the adsorption and thermalcracking of the heavy hydrocarbons. Uptake values and thermal behavior of adsorbed species with and without heptane or DCM washing suggested different types of adsorbed hydrocarbons between the in-situ prepared and the commercial alumina particles. Significant reduction in the viscosity and increase in the oAPI gravity were reported for samples undergoing thermalcracking for 2 h while containing 10000 ppm of alumina nanoparticles under 400°C, 0 rpm in a batch system arrangement. These conditions also resulted in the highest resins to asphaltenes, R/A, ratio and, thus the most stable product.