Engineering Commons^™

Experimental Investigation Of The Interface And Wetting Characteristics Of Rock-H2-Brine Systems For H2 Geological Storage, Mirhasan Hosseini

Theses: Doctorates and Masters

The projected rise in demand for hydrogen (H2) production is a response to several factors, including greenhouse gas emissions caused by burning fossil fuels, depletion of fossil fuel reserves, and their uneven distribution around the earth. Thus, increased requirement for large-scale hydrogen storage solutions is anticipated to overcome imbalance between energy demand and supply. Deep underground formations such as salt caverns and porous reservoir rocks (e.g., depleted hydrocarbon reservoirs and deep saline aquifers) are necessary to achieve such volumes in practice. This process is known as underground hydrogen storage (UHS) which is technically very similar to underground natural gas storage. …

Synthesis Of N-Doped Tio2 Nanoparticles With Enhanced Photocatalytic Activity For 2,4-Dichlorophenol Degradation And H2 Production, Javed Ali Khan, Murtaza Sayed, Noor S. Shah, Sanaullah Khan, Ashfaq Ahmad Khan, Muhammad Sultan, Ammar M. Tighezza, Jibran Iqbal, Grzegorz Boczkaj

All Works

Nitrogen-doped titanium dioxide (N-TiO2) nanoparticles were prepared using a modified sol-gel method. The as-prepared nanoparticles were characterized by state-of-the-art techniques for their optical, structural and morphological properties. The crystallite size, surface area and bandgap energy of reference TiO2 and N-TiO2 nanoparticles were found to be 16.1 and 10.9nm, 83.6 and 131.8 m2 g−1 and 3.23 and 2.89eV, respectively. The photocatalytic activities, in terms of 2,4-dichlorophenol (2,4-DCP) degradation, of reference TiO2 and N-TiO2 were found to be 46.9 and 65.4% at 120min of treatments under UV light irradiation and 21.5 and 77.6% at 240min of treatment under visible light irradiation, employing …

Investigations Of A Surrogate Fuel Based On Fischer-Tropsch Gtl And Ctl In Cvcc, Idi And Di Compression Ignition Engines, Amanda C. Weaver

College of Graduate Studies: Theses & Dissertations

With the increase in availability, feedstocks, and properties of alternative fuels, compatibility issues emerge between current engine platforms often requiring a limit on the blend percentage of alternative fuel in conventional fuel or alteration to the engine platform. Two key metrics were identified, autoignition quality and lubrication characteristics, as vital for the proper function of a compression ignition engine, and if the blend of alternative fuels matches these two criteria for the diesel standard, then the resulting blend percentage can be considered as a viable alternative for complete replacement of conventional petroleum ULSD. Autoignition quality was matched using blends S-8, …

Nonlinear Dynamic Analysis And Control Of Chemical Processes Using Dynamic Operability, San Quan Dinh

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nonlinear dynamic analysis serves an increasingly important role in process systems engineering research. Understanding the nonlinear dynamics from the mathematical model of a process helps to find the boundaries of all achievable process conditions and identify the system instabilities. The information on such boundaries is beneficial for optimizing the design and formulating a control structure. However, a systematic approach to analyzing nonlinear dynamics of chemical processes considering such boundaries in a quantifiable and adaptable way is yet to exist in the literature. The primary aim of this work is to formulate theoretical concepts for dynamic operability, as well as develop …

Dynamic Modeling, Data Reconciliation, Parameter Estimation, And Health Monitoring Of A Supercritical Power Plant, Katherine Grace Hedrick

Graduate Theses, Dissertations, and Problem Reports (ETD)

With the introduction of a larger portion of renewable sources of power coming onto the U.S. power grid in recent decades, the operational strategy of coal-fired power plants has changed significantly to focus more on flexibility in response to the changing energy market. This has naturally led to different operational challenges. Many of these challenges are focused on the boilers within these plants, as they are producing more emissions and experiencing increased damage during load-following, which in turn leads to increased costs from penalties for not achieving emission standards or maintenance costs as boilers accumulate damage from the cycling behavior. …

Modular Supply Network Optimization Of Renewable Ammonia And Methanol Co-Production, Benjamin Akoh

Graduate Theses, Dissertations, and Problem Reports (ETD)

To reduce the use of fossil fuels and other carbonaceous fuels, renewable energy sources such as solar, wind, geothermal energy have been suggested to be promising alternative energy that guarantee sustainable and clean environment. However, the availability of renewable energy has been limited due to its dependence on weather and geographical location. This challenge is intended to be solved by the utilization of the renewable energy in the production of chemical energy carriers. Hydrogen has been proposed as a potential renewable energy carrier, however, its chemical instability and high liquefaction energy makes researchers seek for other alternative energy carriers. Ammonia …

Ambient Ammonia Synthesis Via Microwave-Catalytic Materials And Plasma Chemistry, Siobhan Brown

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ammonia is critical to supporting human life on earth because of its use as fertilizer. The Haber-Bosch process to produce ammonia has been practiced for over 100 years. This process operates at high pressure and temperature to overcome the thermodynamic and kinetic limitations of the ammonia synthesis reaction thus researchers have tried to overcome it for decades. At present this process represents 1% of global energy usage and 2.5% of global CO₂ emissions. The proposed chemical looping ammonia synthesis approach seeks to reduce the environmental impact of this critical process and to elucidate microwave-catalytic principles.

This research aims to …

Optimal Design And Operation Of Integrated Hydrogen Generation And Utilization Plants, Ijiwole Solomon Ijiyinka

Graduate Theses, Dissertations, and Problem Reports (ETD)

There are considerable efforts worldwide for reducing the use of fossil fuel for energy production. While renewable energy sources are being increasingly used, fossil fuel still contribute about 80% of the energy used worldwide. As a result, the level of CO₂ is still increasing fast in the atmosphere currently exceeding about 410 parts per million (ppm). For reducing CO₂ build up in the atmosphere, various approaches are being investigated. For the electric power generation sector, two key approaches are post-combustion CO₂ capture and use of hydrogen as a fuel for power generation. These two solutions can also …

Microwave-Assisted Ammonia Synthesis Over Cs-Ru/Ceo2 Catalyst, Alazar Kesete Araia

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ammonia synthesis is one of the greatest innovations of the 20^th century with extensive applications from fertilizers to intermediates for nitrogen-containing chemicals and pharmaceuticals. Annually, more than 242 million tons of ammonia is produced globally, supporting approximately 27% of the world’s population. One of the fast-growing applications for ammonia is as H₂ energy carrier due to its high energy storage capacity, considered to be a decarbonized energy source. The low volumetric energy density and incompressibility makes Hydrogen a non-preferable energy carrier; an alternative carrier becomes a requirement. Ammonia possesses unique property as an energy-dense carrier to store and …

Combustion Characteristics Of Methane, Ethane, Propane, And Butane Blends Under Conditions Relevant Of A Dual-Fuel Diesel And Natural Gas Engine, Christopher Joseph Ulishney

Graduate Theses, Dissertations, and Problem Reports (ETD)

As natural gas production infrastructure is already in place in most of the world and will continue expanding for the foreseeable future, natural gas is an alternative to traditional liquid petroleum fuels in heavy-duty engines. Dedicated natural gas or dual-fuel diesel-natural gas heavy-duty engines are alternatives to diesel-only power generation equipment. One challenge is the large variation in the natural gas composition available for such applications, which is known to significantly affect engine’s combustion characteristics and the emissions composition. As the literature on dual-fuel combustion under low load engine operating conditions that use more realistic natural gas mixtures (i.e., mixtures …

Modeling And Simulation Of A Process That Converts Ethane To Ethylene And Ethylene To Low Density Polyethylene, Ernest Bosire Mokaya

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ethylene is a critical feedstock and a major building block in the petrochemical industry that is used in synthesizing important products like polyethylene, ethanol, ethylene oxide, ethylene dichloride and ethylbenzene. With increasing demand of plastics, production of ethylene and subsequently polyethylene has increased globally. This thesis conducts the modeling and simulation of an integrated process that utilizes ethane as the primary feedstock to produce ethylene and the subsequent polymerization of ethylene to low-density polyethylene (LDPE). The process combines two different processes into one integrated process: (1) conversion of ethane to ethylene and (2) conversion of ethylene to LDPE. First, a …

Machine Learning Assisted Framework For Advanced Subsurface Fracture Mapping And Well Interference Quantification, Mohammad Faiq Adenan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The oil and gas industry has historically spent significant amount of capital to acquire large volumes of analog and digital data often left unused due to lack of digital awareness. It has instead relied on individual expertise and numerical modelling for reservoir development, characterization, and simulation, which is extremely time consuming and expensive and inevitably invites significant human bias and error into the equation. One of the major questions that has significant impact in unconventional reservoir development (e.g., completion design, production, and well spacing optimization), CO2 sequestration in geological formations (e.g., well and reservoir integrity), and engineered geothermal systems (e.g., …

Synthesis Of Quasi-Freestanding Graphene Films Using Radical Species Formed In Cold Plasmas, Michael A. Mathews Jr.

Graduate Theses, Dissertations, and Problem Reports (ETD)

For over a decade, the Stinespring laboratory has investigated scalable, plasma assisted synthesis (PAS) methods for the growth of graphene films on silicon carbide (SiC). These typically utilized CF₄-based inductively coupled plasma (ICP) with reactive ion etching (RIE) to selectively etch silicon from the SiC lattice. This yielded a halogenated carbon-rich surface layer which was then annealed to produce the graphene layers. The thickness of the films was controlled by the plasma parameters, and overall, the process was readily scalable to the diameter of the SiC wafer.

The PAS process reproducibly yielded two- to three-layer thick graphene films …

Comparative Analysis Of Artificial Intelligence And Numerical Reservoir Simulation In Marcellus Shale Wells, Arya Maher Sattari

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation addresses the limitations of conventional numerical reservoir simulation techniques in the context of unconventional shale plays and proposes the use of data-driven artificial intelligence (AI) models as a promising alternative. Traditional methods, while providing valuable insights, often rely on simplifying assumptions and are constrained by time, resources, and data quality. The research leverages AI models to handle the complexities of shale behavior more effectively, facilitating accurate predictions and optimizations with less resource expenditure.

Two specific methodologies are investigated for this purpose: traditional numerical reservoir simulations using Computer Modelling Group's GEM reservoir simulation software, and an AI-based Shale Analytics …

The Effect Of Different Fracturing Fluids On The Productivity Of Multi-Staged Fractured Marcellus Shale Horizontal Wells, Vida Gyaubea Matey-Korley

Graduate Theses, Dissertations, and Problem Reports (ETD)

While hydraulic fracturing has undeniably improved the production from oil and gas reservoirs, this technology is not without limitations. The primary hurdles lie in the areas of proppant transport, fluid rheology, and stress management. Despite the extensive research conducted in this domain, there remains a considerable amount of work to be done for comprehensive solutions that account for the complex interactions among fracturing fluid, proppant distribution, and geomechanical conditions. Achieving this will then make room for a holistic and efficient hydraulic fracturing strategy.

This study addresses the above-mentioned problem by examining the impact of fluid type on proppant transport and …

Leveraging Artificial Intelligence And Geomechanical Data For Accurate Shear Stress Prediction In Co2 Sequestration Within Saline Aquifers (Smart Proxy Modeling), Munirah Alawadh

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research builds upon the success of a previous project that used a Smart Proxy Model (SPM) to predict pressure and saturation in Carbon Capture and Storage (CCS) operations into saline aquifers. The Smart Proxy Model is a data-driven machine learning model that can replicate the output of a sophisticated numerical simulation model for each time step in a short amount of time, using Artificial Intelligence (AI) and large volumes of subsurface data. This study aims to develop the Smart Proxy Model further by incorporating geomechanical datadriven techniques to predict shear stress by using a neural network, specifically through supervised …

Phosphorus Release And Recovery From Simulated Ferric Wastewater Sludge, Aseel Alnimer

Theses and Dissertations (Comprehensive)

Phosphorus (P) is a fundamental element necessary for all life forms and a key component in the fertilizer industry. Meanwhile, the excessive load of P to water bodies due to human activities has the potential to promote eutrophication. Wastewater treatment plants remove P either biologically or chemically and produce P rich sludge which could be a potential renewable source for P. At present, commercial technologies exist for P recovery from biological wastewater sludge. However, P recovery from chemical sludge particularly iron(III)-phosphate (Fe-P) sludge generated in chemical P removal plants that use iron(III) salts remains a challenge.

This study explored, in …

Faceted Nanomaterial Synthesis, Characterizations And Applications In Reactive Electrochemical Membrane Filtration, Qingquan Ma

Dissertations

Facet engineering of nanomaterials, especially metals and metal oxides has become an important strategy for tuning catalytic properties and functions from heterogeneous catalysis to electrochemical catalysis, photocatalysis, biomedicine, fuel cells, and gas sensors. The catalytic properties are highly related to the surface electronic structures, surface electron transport characteristics, and active center structures of catalysts, which can be tailored by surface facet control. The aim of this doctoral dissertation research is to study the facet-dependent properties of metal or metal oxide nanoparticles using multiple advanced characterization techniques. Specifically, the novel atomic force microscope-scanning electrochemical microscope (AFM-SECM) and density functional theory (DFT) …

Hydrodynamic Investigation Of The Discharge Of Complex Fluids From Dispensing Bottles Using Experimental And Computational Approaches, Baran Teoman

Dissertations

The discharge of non-Newtonian, complex fluids through orifices of industrial tanks, pipes, dispensers, or packaging containers is a ubiquitous but often problematic process because of the complex rheology of such fluids and the geometry of the containers. This, in turn, reduces the discharge rate and results in residual fluid left in the container, often referred to as heel. Heel formation is undesired in general, since it causes loss of valuable material, container fouling, and cross-contamination between batches. Heel may be of significant concern not only in industrial vessels but also in consumer packaging. Despite its relevance, the research in this …

Microhydrodynamic, Kinetic And Thermal Modeling Of Wet Media Milling For Process Optimization And Intensification, Gulenay Guner

Dissertations

Nanoparticle production by wet stirred media milling (WSMM) is a common method for the formulation of poorly water-soluble drugs. While most of the studies in the WSMM literature focus on the formulation aspects to overcome the stability challenges, a thorough mechanistic understanding of the process is lacking, and the process is slow, costly, and energy-intensive. This dissertation presents experimental and modeling work with the ultimate goals of (i) gaining a deeper and more mechanistic understanding of the WSMM process and breakage kinetics of the particles using a microhydrodynamic model with various improvements and advancements, (ii) examining the heat dissipation during …

Lead Acid Battery Recycling In The Current Tanzania Industrialization Drive: Challenges And Opportunities, Divina D. Kaombe

Tanzania Journal of Engineering and Technology (TJET)

ABSTRACT Advancements in automotive technologies, Information and Communications Technology and renewable energy technologies have increased the use of lead acid batteries as a source of portable and rechargeable energy. This has considerably increased the number of spent batteries with adverse effects on the environment and human health; which calls for recycling of spent batteries. This work was conducted to investigate challenges facing the formal business of recycling spent batteries and potential manufacturers of new lead-acid batteries in Tanzania. The work involved collection of information from key stakeholders such as collectors, dealers, Tanzania Revenue Authority and recyclers. It was found out …

Laboratory Analyzes For Determining The Antioxidant Activity Of Dried Red Hawthorn Fruits, T T. Raxmanova, N A. Afanaseva, Sh A. Sultanova

Technical science and innovation

This article analyzes the drying process of hawthorn fruit found in mountainous regions of our country. Since red hawthorn fruit is considered one of the main medicinal products, it is important to dry it while preserving its antioxidant properties. Blanching technology was used in a convective drying device for drying while maintaining the antioxidant properties of the object. In the process of blanching, a solution of ordinary water and citric acid was used. 1 and 1.5% solution of citric acid solution was selected. Blanching technology was used before drying the hawthorn fruit. Red hawthorn fruit was dried until 15% moisture …

A Novel Biomaterial Platform For Cardiac Tissue Engineering, Andrew House

Dissertations

Heart disease is one of the leading causes of death in the world. With a growing demand for in vitro cardiac models that can recapitulate the complex physiology of the cardiac tissue, there is a desire to create novel therapies and treatments. However, due to a lack of fundamental understanding of the heart's inflammatory response to myocardial infarction, the development of new therapies is both time consuming and costly. In this work, a novel approach to fabricating a dynamic hydrogel cardiac platform is reported. This platform better mimics the dynamic changes occurring in the native cardiac tissue microenvironment during cardiac …

Manufacturing Of Instrument Structures From Formed Silicide Films, I R. Bekpulatov

Technical science and innovation

This work provides information on the formation of the main part of thermal radiation receivers. In addition, the article defines and creates optimal modes for creating targets for magnetron sputtering from higher manganese silicide (Mn4Si7) and cobalt monosilicide (CoSi). As is known, the device is formed from a two - type film, where the Mn4Si7 film gives the p - type, and the CoSi film gives the n - type. Films were formed using these targets by magnetron sputtering and their electrophysical properties were studied. The results obtained showed that the resulting films …

Preparation Of Azomethine Derivatives (Schif Bases) Chitosan Apis Mellifera, A S. Mengliev, G A. Ikhtiyarova

Technical science and innovation

Chitin and chitosan should be considered as derivatives of cellulose. The basis for such an approach to these polysaccharides is their chemical structure. The macromolecular chains of these polymers are formed by glucopyranose cycles, which, being connected by β- (1→4) glucosidic bonds, form linear polymer chains. The biological functions and mechanical properties of these polysaccharides are largely determined by the conformation of macromolecules and the distribution of reactive groups in them. Due to the unique properties of chitin and chitosan, they are becoming increasingly important in the practical and especially in the medical and biological activities of mankind. The aim …

Design And Implementation Of Cardiopulmonary Resuscitation Simulation Model, Mbazingwa Mkiramweni

Tanzania Journal of Engineering and Technology (TJET)

Cardiopulmonary resuscitation (CPR) is a life-saving procedure that can multiply a person's chances of survival after a cardiac arrest. The effectiveness of CPR procedures is heavily influenced by the individual skills of the rescuer providing assistance. Chest compressions delivered at an appropriate depth and rate, allowing full chest recoil and with minimal interruptions, are critical for improving cardiac arrest survival. The lack of quality CPR training models in developing countries has a significant impact on the quality of CPR training and skills acquired. Therefore, in this paper, we aim at improving CPR training by designing a high-fidelity CPR training manikin. …

Synthesis, Characterisation And Catalytic Evaluation Of Castor Oil-Templated Mesoporous Sulfated Solid Acid Catalysts For Esterification Reaction, Steven Nyandoro Pr

Tanzania Journal of Engineering and Technology (TJET)

In bio-refinery and other catalytic reactions, heterogeneous catalysts confer advantage over homogenous catalysts due to minimized recovery and separation costs. However, templating surfactant and solid support for the synthesis of heterogeneous catalysts ought to consider their cheap sources and environmentally friendliness for their sustainable use. Thus, with the vision to make the process significantly benign, in the present work, solid acids were synthesised from renewable sources (castor oil as surfactant and rice husk as the source of silica). The synthesised castor oil-templated mesoporous sulfonic acid modified catalysts (SO3H-MTS and SO3H-MT-RHS) were characterised and evaluated for catalytic esterification of acetic acid …

Optimization Of Pulsed Laser Deposition Parameters For Single Crystalline (011) Oriented Tetragonal Pzt Thin Films, Mahamudu H. Mtebwa

Tanzania Journal of Engineering and Technology (TJET)

Recent advances in nanotechnology applications require the processing of high-quality thin films. A systematic study of the optimization of Pulsed deposition parameters for (110) oriented tetragonal PZT thin films is reported in this work. Prior to film deposition, a highly tetragonal Pb(Zr0.5, Ti0.95) or PZT 05/95 was selected to be deposited on (110) oriented Strontium titanate, SrTiO3 substrate, STO(110) to insure small compressive misfit strain. Unlike SRO, the LSOM bottom electrode was then successfully grown at 620 °C, 1.0 J/cm2 and a target-substrate distance of 3.9 cm. Finally, deposition parameters of PZT were progressively optimized through monitoring film morphological changes. …

Performance Evaluation Of Udsm Network To Deliver Multimedia Elearning Contents: Case Of Coict, Mercy Mbise

Tanzania Journal of Engineering and Technology (TJET)

The use of technology in education in Sub-Saharan Africa has been reported to be hindered by many factors including inadequate Information and Communication Technology (ICT) infrastructure, low internet speed, and lack of skills to use educational technologies. This paper aim at evaluating how the available ICT infrastructure at the College of Information and Communication Technologies (CoICT) can support, with acceptable Quality of Service (QoS), the delivery of multimedia applications for eLearning services. The evaluation was performed over a network testbed implemented in a computer laboratory for wired and wireless connections. The testbed consisted of five personal computers (PCs) connected via …

Properties Of (Cd, Zn)S Films Deposited By Dc Co-Sputtering, Lwitiko P. Mwakyusa

Tanzania Journal of Engineering and Technology (TJET)

CdS thin film is commonly used as a buffer layer in most thin film solar cells. However, the buffer layer with less absorption in the visible region of the solar spectrum as well as that which provides perfect lattice matching with the absorbers is required. The incorporation of Zn in the CdS films can affect the structural and optical properties of the buffer layer. In this work, films of CdS and (Cd,Zn)S films were deposited by DC sputtering utilizing CdS and Zn targets. The concentration of Zn in the CdS was varied by changing the sputtering power of the Zn …