• Login
    View Item 
    •   Home
    • UA Graduate and Undergraduate Research
    • UA Theses and Dissertations
    • Dissertations
    • View Item
    •   Home
    • UA Graduate and Undergraduate Research
    • UA Theses and Dissertations
    • Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of UA Campus RepositoryCommunitiesTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournalThis CollectionTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournal

    My Account

    LoginRegister

    About

    AboutUA Faculty PublicationsUA DissertationsUA Master's ThesesUA Honors ThesesUA PressUA YearbooksUA CatalogsUA Libraries

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    The Role of Water in the Energy-Water-Food Nexus: Optimization of Solar Desalination Systems and Novel Scaling Prevention Systems

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    azu_etd_16185_sip1_m.pdf
    Size:
    5.410Mb
    Format:
    PDF
    Download
    Author
    Moore, Sarah
    Issue Date
    2018
    Keywords
    Desalination
    Membrane Distillation
    Modeling
    Optimization
    Phosphorous
    Struvite
    Advisor
    Saez, Avelino E.
    
    Metadata
    Show full item record
    Publisher
    The University of Arizona.
    Rights
    Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
    Abstract
    Increasing demand in energy, water, and food industries necessitates considerations of the inextricable links between them to support sustainable growth. This dissertation explores the role of water in the energy-water-food nexus through discussion of three research projects. The first research project explores the energy-water nexus by discussing optimized solar-driven desalination systems for providing drinking water in remote areas. Many remote communities are disproportionately affected by water scarcity. Some regions have access to saline water sources, making desalination a viable method for mitigating water scarcity. However, these regions may lack access to central power, making solar driven desalination a potential solution. The objective of this research was to develop process models to simulate the non-steady operation of solar driven desalination technologies. Models were used to quantify the system efficiency or cost of water. Non-linear multi-variable optimization was performed to optimize the system by adjusting equipment sizes and operating parameters. In all cases, membrane distillation systems were more expensive than traditional solar desalination technologies. However, the cost of membrane distillation systems may be reduced by reducing costs of membrane modules and solar thermal collectors. The second research project explores the water-food nexus by discussing methods of recovering nutrients from domestic wastewater to secure a novel fertilizer source for sustainable food production. Phosphorous, an essential fertilizer component, is in short supply. However, there are high levels of phosphorous in municipal wastewater. Methods of recovering phosphorous are of great interest. Struvite (MgNH4PO4∙6H2O) is an insoluble mineral that forms in waters rich in phosphorous, especially in municipal wastewater treatment plants. Struvite scaling in processing equipment and pipes causes significant processing problems, but can be beneficial in a controlled environment as it can be recovered and used as fertilizer to help mitigate current phosphorous shortages. Current struvite control technologies, including ferric chloride, make recovery difficult, so alternatives are needed. A potential alternative is application of residual biogas, a byproduct of wastewater treatment rich in carbon dioxide, to lower the pH of wastewater as struvite is more soluble at low pH. CO2 may be easily stripped from solution, allowing for more economical struvite recovery. The purpose of this study was to investigate the feasibility of using residual carbon dioxide for struvite control. Bench- and pilot-scale experiments demonstrated the feasibility of using carbon dioxide to prevent struvite formation. Models were developed to predict the pH upon carbon dioxide addition and validated using experimental results. Finally, the models were used to develop a design tool to facilitate rapid implementation of sustainable struvite control systems at any wastewater treatment plant. This will allow for economical recovery of nutrients from wastewater to support expansion of sustainable farming practices. In the third and final project, the efficacy of a novel ion exchange material for removal of silica from cooling tower water was investigated. Silica is ubiquitous in industrial wastewaters and causes several scaling, prohibiting the recovery and reuse of wastewater. Calcined hydrotalcite (HTC) was demonstrated to be effective in selectively removing silica in batch and continuous experiments in the presence of competing cations. This technology represents a low-cost solution to silica scaling and will help reduce the water requirements of power generation and other industrial processes.
    Type
    text
    Electronic Dissertation
    Degree Name
    Ph.D.
    Degree Level
    doctoral
    Degree Program
    Graduate College
    Chemical Engineering
    Degree Grantor
    University of Arizona
    Collections
    Dissertations

    entitlement

     
    The University of Arizona Libraries | 1510 E. University Blvd. | Tucson, AZ 85721-0055
    Tel 520-621-6442 | repository@u.library.arizona.edu
    DSpace software copyright © 2002-2017  DuraSpace
    Quick Guide | Contact Us | Send Feedback
    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.