Matching Items (6)
Description
Thermodynamic development and balance of plant study is completed for a 30 MW solar thermochemical water splitting process that generates hydrogen gas and electric power. The generalized thermodynamic model includes 23 components and 45 states. Quasi-steady state simulations are completed for design point system sizing, annual performance analysis and sensitivity analysis. Detailed consideration is given to water splitting reaction kinetics with governing equations generalized for use with any redox-active metal oxide material. Specific results for Ceria illustrate particle reduction in two solar receivers for target oxygen partial pressure of 10 Pa and particle temperature of 1773 K at a design point DNI of 900 W/m2. Sizes of the recuperator, steam generator and hydrogen separator are calculated at the design point DNI to achieve 100,000 kg of hydrogen production per day from the plant. The total system efficiency of 39.52% is comprised of 50.7% hydrogen fraction and 19.62% electrical fraction. Total plant capital costs and operating costs are estimated to equate a hydrogen production cost of $4.40 per kg for a 25-year plant life. Sensitivity analysis explores the effect of environmental parameters and design parameters on system performance and cost. Improving recuperator effectiveness from 0.7 to 0.8 is a high-value design modification resulting in a 12.1% decrease in hydrogen cost for a modest 2.0% increase in plant $2.85M. At the same time, system efficiency is relatively inelastic to recuperator effectiveness because 81% of excess heat is recovered from the system for electricity production 39 MWh/day and revenue is $0.04 per kWh. Increasing water inlet pressure up to 20 bar reduces the size and cost of super heaters but further pressure rises increasing pump at a rate that outweighs super heater cost savings.
ContributorsBudama, Vishnu Kumar (Author) / Johnson, Nathan (Thesis advisor) / Stechel, Ellen (Committee member) / Rykaczewski, Konrad (Committee member) / Phelan, Patrick (Committee member) / Wang, Robert (Committee member) / Arizona State University (Publisher)
Created2018
Description
Part of the AORA and LightWorks collaboration in utilizing exhaust heat for the AORA Tulip is the purpose to design a heat transport system that meets system requirements. The investigation included research in potential fluids, equipment, costs, and conducting an analysis to determine favorably fluids. The operating range of the system is 100℃ to 200℃ from the 270℃ exhaust heat 30 meters high. The best, affordable heat transfer fluids (HTF) for this operating temperature range are: XCELTHERM CA, XCELTHERM 600, XCELTHERM 315, Therminol 55, Paratherm NF, Water, Dynalene PG-XT, and Dynalene HC-20. These fluids consist of synthetic oils, mineral oils, propylene glycol, potassium formate/water-based, and water. The ideal operating temperature and HTF depends on the location, accessibility to these fluids, and load application for the heat transport system design. Furthermore, the cost of electricity in the area is a factor for whether the system should use a variable speed drive on the pump. Water is the ideal heat transfer fluid if the operating temperature doesn’t exceed 170℃ and can be readily maintained to avoid corrosion. It has the lowest initial cost and most favorable heat transfer characteristics. The potassium formate/water-based Dynalene HC is the next best choice if the operating temperature doesn’t exceed 210℃. It has similar heat transfer characteristics, but costs more. Lastly, if the operating temperature range exceeds 210℃, then XCELTHERM 600 (white oil) is likely the best HTF to use. It has an operating range up to 315℃, has favorable characteristics, the most affordable oil price, is food contact rated, and has one of the longest life of any fluid of its type.
ContributorsHickey, Andrew William (Author) / Phelan, Patrick (Thesis director) / Stechel, Ellen (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Dr. Ivan Ermanoski has been working towards creating a thermochemical reactor for the purposes of hydrogen production for several years. After testing the initial design, there were found to be several areas in which possible improvements could be made. It is the purpose of this thesis project to look over the shortcomings of the previous reactor design and make improvements. The primary focus of these improvements centers around increasing the heat retention of the reactor, with a secondary focus on improving the workability and ease of construction for the reactor.
ContributorsWehe, Alexander (Author) / Ermanoski, Ivan (Thesis director) / Miller, James (Committee member) / Stechel, Ellen (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2023-05
Description
This research will utilize the energy and poverty alleviation framework to investigate a sustainable energy ecosystem for the Wakapoa indigenous community of Guyana. Five questions guide the research – 1) Is there an energy access-development nexus? 2) Can the relationships and trends between key development indicators and electricity access guide policymakers on development activities? 3) Can small-scale concentrated solar and biomass systems provide adequate electrical power to meet the Wakapoa community's domestic and commercial loads economically? 4) What added social value could be generated from the energy system as per Wakapoa context? and 5) What governance systems can be considered to facilitate a sustainable energy ecosystem? In addressing questions 1 and 2, the research collected secondary data on selected countries' key development indexes from the World Bank and Our World in Data. Datasets include the human development index, human capital index, gross domestic product per capita, gross national income per capita, and electricity access. In addressing questions 3 to 5, the research utilized the convergent research design methods, where an inclusive data collection process targeted fifty (50) community residents as survey participants. Statistical analysis of the survey data proved useful in identifying the community needs for the renewable energy system design options utilizing system advisor model (SAM) software, identifying key economic activities that can add social value to the community, and giving key insight into governance practices preferred by the community. Key findings reveal that electricity access exerts a strong and moderate influence on key development indicators, the concentrated solar power and biomass hybrid system can satisfy the electricity demand of the community at the Tier-5 level that can support many traditional and non-traditional economic activities, while key governance support functions such as the community financial aid fund and community management committee can enhance the sustainability of the various operations as well as residents' well-being and livelihood. Future research can address project financing, community productive capacity, and the marketing of goods and services to promote a sustainable energy ecosystem.
ContributorsKanhai, Mahendra N. (Author) / Chhetri, Nalini (Thesis advisor) / Dirks, Gary (Thesis advisor) / Miller, Clark (Committee member) / Stechel, Ellen (Committee member) / Arizona State University (Publisher)
Created2023
Description
As the need for environmentally friendly and renewable fuel sources rises, many are considering alternative fuel sources, such as solar power. The device explored in this report uses solar power, in theory, to heat a metal oxide, cerium oxide, to a desired temperature. At specific temperatures and pressures, a reaction between an input gas, carbon dioxide or water vapor, and the metal oxide may produce fuel in the form of hydrogen or carbon monoxide. In order to reach the temperatures required by the reaction, a filament inside a high-temperature radiant heater must be heated to the desired temperature. In addition, the system’s pressure range must be satisfied. A pressure and temperature measurement device, as well as a voltage control, must be connected to an interface with a computer in order to monitor the pressure and temperature of different parts of the system. The cerium oxide element must also be constructed and placed inside the system. The desired shape of the cerium oxide material is a tube, to allow the flow of gas through the tubes and system and to provide mechanical strength. To construct the metal oxide tubes, they need to be extruded, dried, and sintered correctly. All the manufactured elements described serve an essential purpose in the system and are discussed further in this document.
This report focuses on the manufacturing of ceria tubes, the construction of a high-temperature radiant heater filament, and the implementation of a pressure measurement device. The manufacturing of ceria tubes includes the extrusion, the drying, and the sintering of the tubes. In addition, heating element filament construction consists of spot-welding certain metals together to create a device similar to that of a light bulb filament. Different methods were considered in each of these areas, and they are described in this report. All of the explorations in this document move towards the final device, a thermochemical reactor for the production of hydrogen (H2) and carbon monoxide (CO) from water (H2O) and carbon dioxide (CO2).
The results of this report indicate that there are several important manufacturing steps to create the most desirable results, in terms of tube manufacturing and heating element design. For the correct tube construction, they must be dried in a drying rack, and they must be sintered in V-groove plates. In addition, the results of the heating element manufacturing indicate that the ideal heating element filament needs to be simple in design (easily fixed), cost-effective, require little construction time, attach to the ends of the system easily, provide mechanical flexibility, and prevent the coil from touching the walls of the tube it lies in. Each aspect of the ideal elements, whether they are tubes or heating elements, is explored in this report.
This report focuses on the manufacturing of ceria tubes, the construction of a high-temperature radiant heater filament, and the implementation of a pressure measurement device. The manufacturing of ceria tubes includes the extrusion, the drying, and the sintering of the tubes. In addition, heating element filament construction consists of spot-welding certain metals together to create a device similar to that of a light bulb filament. Different methods were considered in each of these areas, and they are described in this report. All of the explorations in this document move towards the final device, a thermochemical reactor for the production of hydrogen (H2) and carbon monoxide (CO) from water (H2O) and carbon dioxide (CO2).
The results of this report indicate that there are several important manufacturing steps to create the most desirable results, in terms of tube manufacturing and heating element design. For the correct tube construction, they must be dried in a drying rack, and they must be sintered in V-groove plates. In addition, the results of the heating element manufacturing indicate that the ideal heating element filament needs to be simple in design (easily fixed), cost-effective, require little construction time, attach to the ends of the system easily, provide mechanical flexibility, and prevent the coil from touching the walls of the tube it lies in. Each aspect of the ideal elements, whether they are tubes or heating elements, is explored in this report.
ContributorsCaron, Danielle (Author) / Milcarek, Ryan (Thesis director) / Ermanoski, Ivan (Committee member) / Stechel, Ellen (Committee member) / Mechanical and Aerospace Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Synthesis of Metal Ternary and Quaternary Nitrides with Applications in Renewable Ammonia Production
Description
Ammonia is one of the most important chemicals for modern civilization as well as a potentially invaluable intermediary component of a future sustainable H2 economy, yet its current production is decidedly unsustainable. Accordingly, researchers are attempting to devise new paradigms for ammonia production, one of which would involve the cyclical reaction of H2 with a nitride compound and the renitridation of that compound with N2 - a thermochemical loop that would allow for ammonia production with renewable inputs and at relatively low pressures. In this paper, researchers identified several ternary and quaternary metal nitrides with the potential to exhibit relatively favorable thermodynamics for both the reduction and nitridation steps of that reaction cycle. These compounds were synthesized via co-precipitation and Pechini synthesis and several were tested under gas flows of 75% H2/Ar at 100-700 C and 75% H2/N2 at 700 C to determine their behavior under these conditions. As suggested by the available literature, Co3Mo3N was found to be a far better candidate for thermochemical looping than Fe3Mo3N or Ni2Mo3N - with higher mass loss and mass regain. Interestingly, quaternary nitrides containing Fe and Co in addition to Mo also demonstrated remarkable reduction and nitridation capability under ambient pressures. Ultimately, this paper demonstrates the feasibility of synthesizing a variety of single phase ternary and quaternary nitrides and the potential that several of these nitrides hold for producing ammonia sustainably via cyclic thermochemistry.
ContributorsAnbar, Nathaniel (Author) / Stechel, Ellen (Thesis director) / Navrotsky, Alexandra (Committee member) / Birkel, Christina (Committee member) / Barrett, The Honors College (Contributor) / Historical, Philosophical & Religious Studies, Sch (Contributor) / School of Politics and Global Studies (Contributor) / Chemical Engineering Program (Contributor)
Created2022-05