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Full-Text Articles in Engineering

Bridging Thermochemical And Biochemical Conversion: Impact Of Biochar Addition On The Anaerobic Digestion Of Aqueous Pyrolysis Condensate, Neha Batta Dec 2020

Bridging Thermochemical And Biochemical Conversion: Impact Of Biochar Addition On The Anaerobic Digestion Of Aqueous Pyrolysis Condensate, Neha Batta

Electronic Thesis and Dissertation Repository

Profitable treatment of low value waste biomass is one of the biggest challenges of the industry. Where most of the current treatment strategies, such as pyrolysis, are efficient in complete breakdown of hard to synthesize, low value waste biomass such as lignocellulosic wastes, it leads to the generation of secondary waste thereby compromising its efficiency. The aim of this research is to utilize the aqueous pyrolysis condensate as a feedstock for anaerobic digestion, previously adapting the microbial consortia to the acidity and other potential organic inhibitors present in the APC, to produce energy in the form of biogas following the …


Evolution And Flow Of Vapors In A Fluidized Bed, Hansen Mangaranap Silitonga Dec 2020

Evolution And Flow Of Vapors In A Fluidized Bed, Hansen Mangaranap Silitonga

Electronic Thesis and Dissertation Repository

Vaporization of injected liquid is a key process in many industrial fluidized beds. In Fluid Cokers, for example, quicker vaporization would increase liquid product yield and reduce fouling. A new experimental method was developed to measure the vaporization rate by injecting liquid for a certain duration to reach a constant vaporization rate while monitoring changes in pressure and vapor composition in the exhaust pipe of the fluidization column. Three processes can delay vaporization in a fluidized bed: heat flux from hot-dry particles to wet particles, vapor saturation, and wet agglomerate formation. Operating a spray nozzle at a very high atomization …


Value-Added Lipids Extraction From Wet Microalgae Using Ionic Liquids, Yujie Zhang Dec 2020

Value-Added Lipids Extraction From Wet Microalgae Using Ionic Liquids, Yujie Zhang

Electronic Thesis and Dissertation Repository

Microalgae have gained interest as sources of renewable lipids in the biofuel sector due to their ability to sequester carbon dioxide into triacylglycerol (TAG), a biodiesel feedstock. However, industrial-scale production of microalgae exclusively for fuel production is limited by technical and economic challenges. Some marine microalgae can accumulate large amounts of polyunsaturated fatty acids (PUFAs) such as docosahexaenoic acid (DHA) and other unsaturated fatty acids, which are high-value compounds linked to the prevention of various cardiovascular diseases. This thesis therefore examines the extraction of lipids and DHA from two microorganisms (Chlorella vulgaris, a model organism for lipid production, …


The Effect Of Moox Reducibility On Its Activity For Anisole Hydrodeoxygenation, Chantal Walker Dec 2020

The Effect Of Moox Reducibility On Its Activity For Anisole Hydrodeoxygenation, Chantal Walker

Electronic Thesis and Dissertation Repository

Catalytic hydrodeoxygenation (HDO) is a process for upgrading crude bio-oil as it has a high oxygen content which causes several undesirable properties. Current methods for HDO use sulfided NiMo and CoMo or supported noble metal catalysts which hydrogenate aromatic rings, leading to less valuable products and increasing the hydrogen consumption. Using 10 wt. % MoO3 supported on ZrO2, TiO2, γ-Al2O3, SiO2 and CeO2, we investigated the atmospheric HDO of anisole, a model compound, at 350 °C. All catalysts achieved C – O bond cleavage, preserving the aromatic ring. In situ UV-Vis spectroscopy showed a peak corresponding to intervalence charge transfer …


Numerical Study Of The Effect Of Gas Distributors And Baffles On The Bubble Distribution, Gas And Solid Mixing In A Fluidized Bed, Xuelian Xing Nov 2020

Numerical Study Of The Effect Of Gas Distributors And Baffles On The Bubble Distribution, Gas And Solid Mixing In A Fluidized Bed, Xuelian Xing

Electronic Thesis and Dissertation Repository

In this study, the multi-phase Eulerian-Eulerian two-fluid method (TFM) coupled with the kinetic theory of granular flow (KTFG) was used to investigate hydrodynamics of particle flows (Geldart Group B) in a lab-scale fluidized bed Geldart Group B particles, operating in bubbling and turbulent regimes. The effect of gas distributors and baffles on the distribution of the gas bubbles, and the mixing of gas and solids were investigated under various superficial gas velocities.

The numerical model is validated by experimental results from two different measurement methods with various gas distributor configurations and a superficial gas velocity ranging from 0.4 m/s to …


Cfd Simulations Of Bubble Column Equipped With Bundles Of Concentric Tubes, Glen C. Dsouza Oct 2020

Cfd Simulations Of Bubble Column Equipped With Bundles Of Concentric Tubes, Glen C. Dsouza

Electronic Thesis and Dissertation Repository

Bubble column reactors are multiphase contactors that have found several industrial applications owing to various attractive features including excellent thermal management, low maintenance cost due to simple construction and absence of moving parts. In order to attain desired performance for a given application, these reactors are usually equipped with internals such as vertical tube bundles to facilitate heat transfer. The column hydrodynamics and turbulence parameters are altered when the column is occluded with internals which adds to the complexity of the problem. The use of Computational Fluid Dynamics (CFD) tools for the study of multiphase flows has gained a lot …


Experimental And Numerical Study Of Polymorphism In Crystallization Processes, Mengxing Lin Oct 2020

Experimental And Numerical Study Of Polymorphism In Crystallization Processes, Mengxing Lin

Electronic Thesis and Dissertation Repository

Polymorphism, which is exhibited in more than half of the active pharmaceutical ingredients, has a direct impact on the stability, bioavailability and processability of the product. Despite extensive studies on polymorphism in the field of crystal engineering, the control of polymorphism is still one of the most challenging tasks in pharmaceutical manufacturing.

The aim of this work is to crystallize the desired polymorph with the help of process modeling and process analytical technologies. First, we investigated the crystallization properties of imatinib mesylate, including polymorphism characterization, solubility measurement, polymorphic transformation and kinetic parameter estimation, as they are the fundamental information for …


Material Properties And Heat Transfer Parameters In Compression Molding Of Glass Mat Thermoplastics, Cheng Xu Oct 2020

Material Properties And Heat Transfer Parameters In Compression Molding Of Glass Mat Thermoplastics, Cheng Xu

Electronic Thesis and Dissertation Repository

The compression molding of glass mat thermoplastics (GMT) allows high volume manufacture of composite parts with a short production cycle. Computer simulation is often used to assist process development and optimization. Reliable simulation depends on input of material property parameters and accurate prediction of heat transfer. This thesis developed experimental methods to characterize material property and heat transfer process parameters. Results were obtained by applying the methods to a selected commercial GMT sheet. Heat transfer coefficients including convection coefficients during pre-heating and transfer, as well as contact conductance at sheet-mold interface were estimated by a parameter-fitting approach. Viscoelastic parameters of …


Multiphase Equilibrium In A Novel Batch Dynamic Vl-Cell Unit With High Mixing: Apparatus Design And Process Simulation, Jeonghoon Kong Aug 2020

Multiphase Equilibrium In A Novel Batch Dynamic Vl-Cell Unit With High Mixing: Apparatus Design And Process Simulation, Jeonghoon Kong

Electronic Thesis and Dissertation Repository

The availability of vapor pressure data is essential to validate thermodynamic models and enhance the thermodynamic correlations. Despite its importance, there is limited vapor pressure data of the multicomponent mixtures in open literature. This is the case for hydrocarbon/water blends as they are found in the naphtha recovery unit in the oil sand process.

This thesis uses a CREC-VL-Cell, a batch apparatus to measure the vapor pressures of n-octane/water, synthetic naphtha (SN)/water and solids/n-octane/water. The CREC-VL-Cell operates at thermal equilibrium with less than 1.6 % error using a 1080 rpm impeller speed and various optimized operational factors. This apparatus saves …


Waste Hemp Fibers (Hfs) Derived Porous Carbons: Preparation, Characterization, And Potential Applications, Manju Gurung Aug 2020

Waste Hemp Fibers (Hfs) Derived Porous Carbons: Preparation, Characterization, And Potential Applications, Manju Gurung

Electronic Thesis and Dissertation Repository

The main objective of the present research was to develop environmentally friendly and cost-effective porous carbon materials of improved properties from waste hemp fibers. Two different types/categories of porous carbons were prepared from hemp fibers. In one type, porous carbon materials were developed by a simple one-step method of carbonization and activation. The other type of carbon materials developed in this study were nitrogen-containing activated carbons, which were developed by introduction of nitrogen-containing functional groups on the surface of hemp fibers followed by activation and carbonization. The pore structure/distribution and surface chemistry of the prepared carbons were investigated through the …


Development Of Technologies For High Value Products From Biomass Pyrolysis, Chiara Barbiero Aug 2020

Development Of Technologies For High Value Products From Biomass Pyrolysis, Chiara Barbiero

Electronic Thesis and Dissertation Repository

Phragmites australis (Cav.) Trin. ex. Steud. is an invasive perennial grass found in North America, which is rapidly spreading throughout Ontario, damaging the native ecosystem and endangering the wildlife. This infestation has caused a decrease in biodiversity and nutrient availability to the agricultural crops through competition. One of the most effective management practices is spading them, leaving a huge number of dead stalks that need to be disposed of. Pyrolysis was selected as an alternative thermochemical method to convert this feedstock to value-added bioproducts, such as bio-oil and biochar, and to produce valuable renewable chemicals from the pyrolysis oil, such …


Fluidization Characteristics Of Group C+ Particles: Fine Powder With Nanoparticle Modulation, Yandaizi Zhou Jul 2020

Fluidization Characteristics Of Group C+ Particles: Fine Powder With Nanoparticle Modulation, Yandaizi Zhou

Electronic Thesis and Dissertation Repository

Geldart Group C particles become increasingly attractive in industry because of their small particle sizes and large specific surface areas. The main challenge in the flow and fluidization of Geldart Group C particles is their cohesive nature due to strong interparticle forces. The “nanoparticle modulation” technique was adopted to reduce the interparticle forces of Group C particles and thus significantly improved their flow and fluidization quality. Group C+ particles, a new type of fine particles with drastically reduced or insignificant interparticle forces, were created using the nano-modulation technique.

Fundamental studies provided a comprehensive understanding of the fluidization quality of …


Improved Fermentation Design And Screening Devices For Biobutanol Production, Garret Christopher Munch Jul 2020

Improved Fermentation Design And Screening Devices For Biobutanol Production, Garret Christopher Munch

Electronic Thesis and Dissertation Repository

A worldwide increase in demand for renewable fuels has revived interest in fermentatively produced butanol. However, butanol fermentation suffers from low product yields and productivity. The work presented in this thesis addresses part of these research and development needs at three levels: innovative fermentation process design; genetic manipulation for strain enhancement; and the development of a new tool for anaerobic process characterization and optimization.

Product yield could be increased through traditional fermentation engineering. Co-fermentation of butyric acid with glycerol increased the butanol yield from 0.45 mol/mol (mols C in butanol / mol C in substrates) to 0.51 mol/mol. In building …


Thermo-Catalytic Decarboxylation Of Fatty Acids And Real-World Derivatives Towards Liquid Fuels, Shaun J. Fraser Jun 2020

Thermo-Catalytic Decarboxylation Of Fatty Acids And Real-World Derivatives Towards Liquid Fuels, Shaun J. Fraser

Electronic Thesis and Dissertation Repository

The production of green diesel through waste fats and oils is a promising route to producing renewable transportation fuels that are energy dense, have low oxygen content, low nitrogen content, and possess excellent cold flow properties. However, producing green diesel can be expensive, as most methods use expensive noble metals catalysts such as platinum or palladium, use expensive hydrogen gas, and/or use pyrolysis and thermal cracking to reduce hydrocarbon chain length and lose energetic carbon-hydrogen bonds. This thesis studies the continuous thermo-catalytic decarboxylation of fatty acids and their derivatives to create liquid transportation fuels using an inexpensive MoOx/Al …


Bubble Dynamics In A Sand Fluidized Bed In The Presence Of Biomass Pellets, Nicolas Torres Brauer Jun 2020

Bubble Dynamics In A Sand Fluidized Bed In The Presence Of Biomass Pellets, Nicolas Torres Brauer

Electronic Thesis and Dissertation Repository

Given the worldwide concerns regarding fossil fuel availability, global warming, water, and air pollution and economy needs, there is an urgent requirement to develop and implement alternative energies. Biomass gasification can consume vegetal waste to produce syngas, which is a mix of carbon monoxide, hydrogen, and carbon dioxide. When biomass gasification is carried out in a fluidized bed, the process is highly efficient.

The experimental study of the present Ph.D. dissertation took place in a Plexiglas 0.44 m diameter unit, equipped with a CREC Optiprobe system and a video camera. The unit was filled with 200-900 µm sand particles and …


Design, Fabrication And Applications Of Efficient Conductive Polymers For Photocatalytic Antimicrobials, Chunbo Liu May 2020

Design, Fabrication And Applications Of Efficient Conductive Polymers For Photocatalytic Antimicrobials, Chunbo Liu

Electronic Thesis and Dissertation Repository

Designing new antimicrobial surfaces which are effective under visible light irradiation without leaching toxic ions is a current challenge for effective disinfection. A new polymeric system poly[2,11’-thiophene-ethylene-thiophene-alt-2,5-(3-carboxyl) -thiophene] (PTET-T- COOH) with broad light absorption was synthesized. Its photocatalytic disinfection performance against staphylococcus aureus (S. aureus) and streptococcus suis (S. suis) was evaluated, showing over 99.999% inactivation (higher than 5-log inactivation) in 2 h for both bacteria, under visible light irradiation at a low concentration of PTET-T-COOH (0.1 mg/mL). In addition, a PTET-T-COOH/polyurethane (PU) polymeric coating was designed and fabricated. Chemical attachment was confirmed between PTET-T-COOH and PU using various thermophysical …


Ultrasonic Techniques For Characterizations Of Oils And Their Emulsions And Monitoring Oil Layer Depth Of Spill, Kanu Raigan Apr 2020

Ultrasonic Techniques For Characterizations Of Oils And Their Emulsions And Monitoring Oil Layer Depth Of Spill, Kanu Raigan

Electronic Thesis and Dissertation Repository

Oil-water emulsions encountered during production and refining of crude oil, as well as oil spills present technical challenges. There is need for low-cost technology to understand characteristics such as composition, droplets size distribution and other rheological properties of oils and their emulsions and monitor oil layer depth of spill.

The main purpose of the first part of this work was to develop and test ultrasonic based technology to characterize oils and their emulsions using their acoustic velocities and attenuations. The technique captured an increase in both acoustic velocity and attenuation with asphaltenes concentration in crude oil. Thus, the fast response …


Improvement Of Fluidization Ability For Group A Powders By Fine Powder Additives, Xiaowei Zhang Apr 2020

Improvement Of Fluidization Ability For Group A Powders By Fine Powder Additives, Xiaowei Zhang

Electronic Thesis and Dissertation Repository

Group A powders are widely utilized in the industry because of the great quality of fluidization, which can be affected by the fine content. This project investigates the feasibility that employing the fine powders (≤ 20 μm) as additives to further improve the fluidization ability of Group A powders. Three additives, Coal-15, GB-6, and SiO2-5 are added into FCC-76, based on various volume fractions. The minimum fluidization velocity (Umf), bed expansion ratio (BER), and dense phase expansion ratio (DER) are tested to evaluate the quality of fluidization. Coal-15 can slightly improve the fluidization quality. High …


Light Downshifting Zinc Oxide-Ethylene Vinyl Acetate Nanocomposite Greenhouse Films, David V. Hiscott Mar 2020

Light Downshifting Zinc Oxide-Ethylene Vinyl Acetate Nanocomposite Greenhouse Films, David V. Hiscott

Electronic Thesis and Dissertation Repository

One method to increase the productivity of greenhouse agriculture is to increase the amount of photosynthetically available light within. This was accomplished through the use of nanocomposite greenhouse film comprised of light downshifting zinc oxide quantum dots and ethylene vinyl acetate copolymer. As this material will be used on a commodity scale, two different approaches – a large batch process and continuous plug flow reactor – were designed for mass production of zinc oxide. A design of experiment was performed to determine which synthesis parameters contribute more strongly to the quantum dot’s growth. This was done for a small-scale batch …


Rational Interface Design For High-Performance All-Solid-State Lithium Batteries, Changhong Wang Jan 2020

Rational Interface Design For High-Performance All-Solid-State Lithium Batteries, Changhong Wang

Electronic Thesis and Dissertation Repository

All-solid-state lithium batteries (ASSLBs) have gained substantial attention owing to their excellent safety and high energy density. However, the development of ASSLBs has been hindered by large interfacial resistance originating from the detrimental interfacial reactions, poor solid-solid contact, and lithium dendrite growth. The research in this thesis aims at achieving high-performance ASSLBs via rational interface design and understanding the interfacial reaction mechanisms.

At the cathode interface, an ideal dual core-shell nanostructure was first designed. Moreover, single-crystal LiNi0.5Mn0.3Co0.2O2 (SC-NMC532) cathode was compared with polycrystalline NMC532, the former exhibits much enhanced Li+ diffusion kinetics …


Effects Of Drinking Water Treatment Processes On Removal Of Algal Matter And Subsequent Water Quality, Ziming Zhao Jan 2020

Effects Of Drinking Water Treatment Processes On Removal Of Algal Matter And Subsequent Water Quality, Ziming Zhao

Electronic Thesis and Dissertation Repository

Seasonal algal blooms in drinking water sources have increased significantly over the recent past as a result of increased temperature and nutrient loading in surface water due to agricultural and surface runoff. More than 95% of algal cells can be removed by coagulation and flocculation processes. However, algal organic matter (AOM) is not removed well during coagulation, thus causes several operational challenges in drinking water treatment. This research was conducted to investigate the effectiveness of coagulation, granular activated carbon adsorption, and filtration processes on AOM removal and to evaluate disinfection by-products formation potential with/without UV irradiation.

Initially, coagulation performance for …