Engineering Commons^™

Improving Performance And Durability Of Intermediate Temperature Proton‐Conducting Solid Oxide Electrolysis Cells Via Materials Design And Catalyst Surface Engineering, Hanchen Tian

Graduate Theses, Dissertations, and Problem Reports

Solid oxide steam electrolysis cell, a promising electrical-chemical conversion device for the next generation efficient hydrogen production and energy storage, has been actively studied because of their high energy conversion efficiencies and prospective applications as electrochemical reactors. After decades of research on protonic ceramic materials, remarkable advances have been made in the protonic ceramic electrochemical cells (PCECs) air electrode and electrolyte. However, the existing air electrodes are far from satisfying the requirements of practical applications, a series of issues, including the lack of active and durable electrodes, greatly limit the commercialization. To date, the systematic development of triple conducting catalysts …

Valorization Of Xylan In Agroforestry Waste Streams, Harrison Appiah

Graduate Theses, Dissertations, and Problem Reports

Valorization of Xylan in Agroforestry Waste Streams.

Harrison Appiah

Microwave-assisted deep eutectic solvent and gamma-valerolactone metallic chloride catalyzed conversion of xylan to furfural were investigated using a 2x3 factorial experimental design at two levels of percent microwave power, reaction time, and catalyst concentration. The levels of each factor studied were (20%, 60% microwave power, 2, 4 minutes, and 10, 20mg) respectively. The effect of three metallic chloride catalysts (LiCl, FeCl3.6H20, CuCl2) on the conversion of xylan to furfural was also investigated. The gamma-valerolactone-ferric chloride sent system exhibited the highest mean yield of furfural (56.50%). The next highest furfural yield of …

Process Modeling And Techno-Economic Analysis Of Micro- Encapsulated Carbon Sorbents (Mecs) For Co2 Capture In A Fixed Bed And Moving Bed Reactors, Goutham Kotamreddy

Graduate Theses, Dissertations, and Problem Reports

Carbon capture, utilization, and storage (CCUS) is seen as a suite of technologies to curb the carbon dioxide emissions from the atmosphere and plays a crucial role to meet the net zero emissions target for many countries by 2050. One of the major sources for CO₂ emissions is combustion of fossil fuels. Various innovative capture technologies are being explored because the state-of-the-art monoethanolamine (MEA) based carbon capture technology has drawbacks such as corrosion, energy penalty. There are several potential solvents that have lower energy penalty, but they are highly viscous or may turn into solid phase in the absorber …

Dynamic Modelling And Control Of Grid-Level Energy Storage Systems, Sai Pushpitha Vudata

Graduate Theses, Dissertations, and Problem Reports

The focus of this work is on two energy storage technologies, namely pumped storage hydroelectricity (PHS) and secondary batteries. Under secondary battery technologies, two potential technologies for grid-scale storage, namely high-temperature sodium-sulfur (NaS) battery and vanadium redox flow battery (VRFB), are investigated. PHS is a largescale (>100 MW) technology that stores and generates energy by transporting water between two reservoirs at different elevations. The goal is to develop a detailed dynamic model of PHS and then design the controllers to follow the desired load trajectory accurately with high efficiency. The NaS battery and VRFB are advanced secondary batteries which …

Natural Gas Conversion To Value-Added Chemicals By Microwave Catalytic Processes, Brandon Robinson

Graduate Theses, Dissertations, and Problem Reports

Ethane is the second-largest component in natural gas and is typically separated out to minimize condensation in the pipelines. The technical difficulties and cost associated with the transportation and the storage of ethane have led companies to start burning natural gas to produce power or flaring which attributes to the global CO₂ emission problem. The conversion of ethane to higher-value liquid products is of increasing importance so that the natural gas can be safely utilized and cost-effectively transported. Existing commercial technologies used to convert ethane to liquid chemical products are typically based on the indirect syngas route, such as …

Multimodel Operability Framework For Design Of Modular And Intensified Energy Systems, Vitor Gazzaneo

Graduate Theses, Dissertations, and Problem Reports

In this dissertation, a novel operability framework is introduced for the process design of modular and intensified energy systems that are challenged by complexity and highly constrained environments. Previously developed process operability approaches are reviewed and further developed in terms of theory, application, and software infrastructure. An optimization-based multilayer operability framework is introduced for process design of nonlinear energy systems. In the first layer of this framework, a mixed-integer linear programming (MILP)-based iterative algorithm considers the minimization of footprint and achievement of process intensification targets. Then, in the second layer, an operability analysis is performed to incorporate key features of …

Dynamic Optimization Algorithms For Baseload Power Plant Cycling Under Variable Renewable Energy, Rebecca Hyen Hae Kim

Graduate Theses, Dissertations, and Problem Reports

The growing deployment of variable renewable energy (VRE) sources, such as wind and solar, is mainly due to the decline in the cost of renewable technologies and the increase of societal and cultural pressures. Solar and wind power generation are also known to have zero marginal costs and fuel emissions during dispatch. Thereby, the VRE from these sources should be prioritized when available. However, the rapid deployment of VRE has heightened concerns regarding the challenges in the integration between fossil-fueled and renewable energy systems. The high variability introduced by the VRE as well as the limited alignment between demand and …

Dynamic Modeling Of A Coal Mill For Simultaneous Dynamic Data Reconciliation And Parameter Estimation, Vinayak Dwivedy

Graduate Theses, Dissertations, and Problem Reports

In comparison with other gaseous and liquid fossil fuels used in power production, a coal fired power plants requires additional equipment for fuel preparation. A medium speed mill is usually a preferred equipment which serves in grinding and drying of the raw feed coal. Due to the high recycle of coal particles within a medium speed coal mill, the mill performance is sensitive to the efficiency of grinding and classification operations within mill. The goal of this research is to study the performance of the milling system and develop a method to estimate some of the unmeasured variables, which include …

Simultaneous Activation Of Stable Molecules- Methane And Nitrogen- Using Microwave Reactor With And Without Plasma- To Produce Ethylene And Ammonia, Sarojini Tiwari

Graduate Theses, Dissertations, and Problem Reports

The discovery of stranded natural gas around the world has made shale gas cheaper and widely accessible. This has driven the relevant research towards the direct utilization of Methane (CH4), a major component of natural gas. CH4 is a highly stable molecule, hence its activation and consequent formation of value-added chemicals in a direct and efficient manner is a relevant problem of the 21st century. All the commercial processes convert natural gas to chemicals indirectly, via the formation of syngas followed by several reactions. The conventional systems are energy intensive and one of the major contributors to green-house gas emissions. …

Microwave-Assisted Natural Gas Conversion To Value-Added Chemicals, Xinwei Bai

Graduate Theses, Dissertations, and Problem Reports

Stranded gas is a raw gas mixture of volatile hydrocarbons where the main composition is methane. The producers flare the stranded gas at the site because the cost of collecting and transporting the gas is higher than the value of the gas itself. To reduce the waste of this natural resource, it is worthwhile to utilize the on-site stranded natural gas as feedstock to produce value-added chemicals without emitting greenhouse gas. Direct natural gas conversion process is more desirable because of lower capital investment. Methane and ethane, the two major components of natural gas, are very stable molecules that usually …

Well Performance Analysis Of Mseel1 And Mseel2 Wellpads, Mohammad Faiq Adenan

Graduate Theses, Dissertations, and Problem Reports

MSEEL1 and MSEEL2 are wellpads that were developed as a means of conducting research into how a gas well being developed in the Marcellus shale can be optimized from the reservoir identification stage to the completions and operational stage. This thesis provides a report of the workflow performed to use the generated data from different sources and analyze them for optimization.

MIP-3H and Boggess 17H were designated as science wells, for which the majority of the well logging and coring experiments were conducted on. The data obtained from the experiments were used as a basis for petrophysical analysis, the results …

Biological Conversion Of Carbon Dioxide To Value-Added Chemicals, Owen James Mcgrath

Graduate Theses, Dissertations, and Problem Reports

As Carbon Dioxide (CO₂) levels in the atmosphere continue to rise due to human intervention, there is increased urgency to take actions to mitigate the potential ramifications. Many countries have instituted a CO₂ tax and have provided funding to finding potential solutions to our growing CO₂ problem. Further investigating CO₂ capture, sequestration, and utilization is key to combating rising CO₂ levels and methods being investigated have increased substantially in recent years. Converting CO₂ into fuels and value-added chemicals provides a unique opportunity to create materials of value from a substance that is being …

The Impacts Of The Net Stress And Stress Shadow On The Productivity Of Marcellus Shale Horizontal Well, Mohamed El Sgher

Graduate Theses, Dissertations, and Problem Reports

Shale gas development has become a crucial part of the global oil and gas industry in recent years, especially in North America. Even though the application of horizontal drilling and hydraulic fracturing techniques have successfully unlocked considerable reserves of natural gas in shale-gas reservoirs, production rates from unconventional reservoirs decline more rapidly than conventional reservoirs. This is because production from a reservoir results in an increase in net stress due to a reduction in the pore pressure, while overburden pressure remains constant. This leads to the reduction in permeability of both the matrix and the fissures, as well as the …

Application Of Fiber Optics Das On Completion Design Optimization, Aliou Sylla

Graduate Theses, Dissertations, and Problem Reports

Interstage communication during well stimulation reducing the effectivity of the well completion is known to be a concern in the oil and gas industry. The leading cause of this is fracture communication due to the presence of natural fractures where the formation is being hydraulically fractured. In this study, a technique was developed to map natural fractures, on a larger scale, underground to be able to avoid the high fracture intensity zones when hydraulically fracturing. This study developed a technique to optimize well completion designs by introducing the ability of locating natural fractures zones in the formation (Marcellus Shale) which …

Analyzing And Measuring Petrophysical Properties Of Marcellus Shale, Yahia Mustafa Yassin Mustafa

Graduate Theses, Dissertations, and Problem Reports

Unconventional oil and natural gas play a key role in our nation's future. The U.S. has vast reserves of such resources that are commercially viable as a result of advances in horizontal drilling and hydraulic fracturing technology. These technologies enable greater access to oil and natural gas in shale formations. Responsible development of America's shale gas resources offers important economic, energy security, and environmental benefits. Hydraulic fracturing and horizontal drilling apply the latest technologies and make it commercially viable to recover shale gas and oil.

In order to estimate the original gas-in-place, predict the production rates, and optimize the hydraulic …

Dry Reforming Of Methane Using Microwave Irradiated Metal Oxide/Coal Char Catalysts, Anthony Carter

Graduate Theses, Dissertations, and Problem Reports

This research focuses on the synthesis of both shaped and amorphous powder materials, the combination of these materials with dried Powder River Basin (PRB) coal char, and their reactionary properties with methane and carbon dioxide gasses with conventional and microwave (MW) heating. The first goal of this project was to synthesize shaped micro and nano sized particles with ideal dielectric properties for converting electromagnetic energy into heat and proven capabilities of activating methane. These particles were synthesized via solvothermal, hydrothermal, and co-preceptory treatments alone and onto the surface of dried PRB coal char. PRB is a sub-bituminous, low-ranking coal (LRC) …

Quantifying The Impact Of Load-Following On Gas-Fired Power Plants, Yifan Wang

Graduate Theses, Dissertations, and Problem Reports

Due to rapid penetration of renewables into the grid, natural gas combined cycle (NGCC) power plants are being forced to cycle their loads more frequently and rapidly than for which they were designed. However, the impact of load-following operation on plant efficiency and equipment health are currently poorly understood. The objective of this work is to quantify the impact of load-following on the gas-fired plants by developing high-fidelity multi-scale dynamic models. There are four main tasks in this project. First, dynamic model of an NGCC power plant has been developed. The main components of the NGCC plants are the gas …