University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School March 2020 Enhanced Fluoride Removal in Biosand Filters Using Aluminum Oxide Coated Media and Modified Filter Design Madison Leigh Rice University of South Florida Follow this and additional works at: https://scholarcommons.usf.edu/etd Part of the Environmental Engineering Commons Scholar Commons Citation Rice, Madison Leigh, "Enhanced Fluoride Removal in Biosand Filters Using Aluminum Oxide Coated Media and Modified Filter Design" (2020). Graduate Theses and Dissertations. https://scholarcommons.usf.edu/etd/8288 This Thesis is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Enhanced Fluoride Removal in Biosand Filters Using Aluminum Oxide Coated Media and Modified Filter Design by Madison Leigh Rice A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Environmental Engineering Department of Civil and Environmental Engineering College of Engineering University of South Florida Co-Major Professor: Sarina J. Ergas, Ph.D. Co-Major Professor: Kebreab Ghebremichael, Ph.D. Katherine Alfredo, Ph.D. Date of Approval: March 19, 2020 Keywords: Full-Scale, Pumice, Biochar, Drinking Water Treatment, Point of Use Copyright © 2020, Madison Leigh Rice Dedication To Warren and my parents, thank you for your love and support. Acknowledgments I would like to pay special regards to Dr. Sarina Ergas for her mentorship and guidance throughout this project. Also to Dr. Kebreab Ghebremichael for his advice and knowledge. I wish to show my gratitude to Dr. Katherine Alfredo for taking the time to teach me and provide valuable feedback. I would like to thank Xia Yang for working alongside me and supporting this project through thick and thin, I wish her the utmost success with her PhD research. Jordin Kahler and Kammie Kisling provided crucial support for the construction and operation of the filters, I wish them both luck in their future endeavors. A special thank you to Michelle Henderson for mentoring me and introducing me to research during my undergraduate degree. Thank you to Laurie Walker, Kevin Slaughter, and Kim Hutton at the USF Botanical Gardens for their support and for providing the space for us to construct and operate the filters. Special shout-out to Max the garden cat for being a ray of sunshine. I would like to thank the rest of my lab group for being supportive and making research fun. I would like to acknowledge the Richard M. Stessel Memorial Scholarship, as well as the Roy W. Likins Scholarship, for their financial support. This work was made possible by the Joy McCan Foundation. Table of Contents List of Tables ................................................................................................................................. iii List of Figures ................................................................................................................................ iv Abstract ............................................................................................................................................v Chapter 1: Introduction ....................................................................................................................1 Chapter 2: Literature Review ...........................................................................................................7 2.1 Fluoride in Drinking Water ............................................................................................7 2.2 Defluoridation ................................................................................................................8 2.2.1 Membrane Processes .......................................................................................8 2.2.2 Coagulation/Precipitation .............................................................................10 2.2.3 Adsorption.....................................................................................................11 2.3 Aluminum Oxide .........................................................................................................15 2.3.1 Physical and Chemical Characteristics .........................................................15 2.3.2 Media Coating ...............................................................................................16 2.4 Point of Use Drinking Water Treatment ......................................................................17 2.5 Alternate Biosand Filter Media ....................................................................................19 2.5.1 Pumice...........................................................................................................20 2.5.2 Biochar ..........................................................................................................21 2.6 Biosand Filter Design Modifications ...........................................................................22 Chapter 3: Materials and Methods .................................................................................................23 3.1 Materials ......................................................................................................................23 3.1.1 Media ............................................................................................................23 3.1.2 Solutions .......................................................................................................24 3.1.3 Filter Construction and Design .....................................................................25 3.2 Fluoride Adsorption Batch Experiments .....................................................................27 i 3.3 Full-Scale Media Coating ............................................................................................29 3.4 BSF Operation .............................................................................................................31 3.5 Analytical Methods ......................................................................................................31 3.6 Statistical Analysis .......................................................................................................31 Chapter 4: Results and Discussion .................................................................................................33 4.1 Aluminum Oxide Coating Batch Experiments ............................................................33 4.2 Full-Scale Field Experiments .......................................................................................36 4.2.1 Uncoated Sand, Pumice, and Biochar BSF Performance .............................36 4.2.2 Coated Sand and Pumice BSFs .....................................................................38 4.2.3 In-Situ Coating Method ................................................................................41 4.2.4 Filter Performance by Stage..........................................................................44 Chapter 5: Conclusions and Recommendations ............................................................................46 References ......................................................................................................................................49 Appendix A: Copyright Permissions .............................................................................................55 ii List of Tables Table 2.1 Fluoride Removal of Some Natural Adsorbents ............................................................14 Table 3.1 Sand, Pumice, and Biochar Media Characteristics ........................................................23 Table 3.2 Summary of Required Solutions ....................................................................................25 Table 3.3 Materials Required to Construct a Bucket-BSF ............................................................26 Table 3.4 Configuration of Media in Each Bucket-BSF................................................................27 Table 3.5 Masses and Volumes of Uncoated and Coated Sand, Pumice, and Biochar Used in Adsorption Batch Experiments ......................................................................................................29 Table 3.6 Method Descriptions ......................................................................................................32 Table 4.1 Average Effluent Water Quality for All Filters .............................................................39 iii List of Figures Figure 1.1 Commercially available BSF ..........................................................................................4 Figure 2.1 Regions with Groundwater Concentrations of Fluoride Above 1.5 mg/L .....................9 Figure 2.2 Cross-Section of a Typical BSF ...................................................................................20 Figure 3.1 Bucket-BSF Design with Single Bucket Cross-Section ...............................................27 Figure 3.2 Full-Scale Coating Setup with Peristaltic Pump ..........................................................30 Figure 3.3 Coated Pumice and Sand Filters After the Full-Scale Coating Process .......................30 Figure 4.1 Aluminum Oxide Coating 24 Batch Adsorption Studies for (A) Pumice, (B) Sand, and (C) Biochar.....................................................................................................................................35