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Wastewater Treatment Using Encapsulated Chabazite In Polyvinyl Alcohol-Sodium Alginate Hydrogel Biofilm Carriers, Susieanna Nevada Persaud Oct 2023

Wastewater Treatment Using Encapsulated Chabazite In Polyvinyl Alcohol-Sodium Alginate Hydrogel Biofilm Carriers, Susieanna Nevada Persaud

USF Tampa Graduate Theses and Dissertations

Nitrogen discharge from wastewater is a global issue and with increased urbanization as well as industrialization, it has become even more essential to develop more efficient wastewater treatment systems. The dominant form of nitrogen in wastewater is ammonium. Biological oxidation of ammonium to nitrite and nitrate is the first step in biological nitrogen removal processes. If left untreated, nitrogen can cause toxicity to aquatic life, unsafe changes in water quality, and eutrophication.

Biofilm carriers can help to improve the efficiency of traditional activated sludge wastewater treatment systems by reducing operating costs and reducing hydraulic retention time. Biofilm carriers also promote …


Characteristics And Hydraulic Behavior Of Adsorptive Media For Use In Permeable Reactive Barriers, Shelby Rocha Jun 2023

Characteristics And Hydraulic Behavior Of Adsorptive Media For Use In Permeable Reactive Barriers, Shelby Rocha

USF Tampa Graduate Theses and Dissertations

The Cargill ditch is located on the property of Se7en Wetlands, a 1600-ac treatment wetland system in Lakeland, Polk County, Florida. The Se7en Wetlands property was previously utilized for phosphate mining prior to the construction of the system. Nonpoint nutrient sources derived from remnants of abandoned phosphate mines – known as “legacy phosphorus” – become mobilized by stormwater runoff and impair surface water bodies by promoting harmful algal blooms (HABs). Thus, the Cargill ditch likely conveys nutrient rich flow resulting from legacy phosphorus and is thought to be one contributing factor in the occurrence of HABs within the treatment wetland …


Modeling Leachate Treatment Processes In Adsorbent-Amended Hybrid Constructed Wetland, Ishfaqun Nisa Mar 2023

Modeling Leachate Treatment Processes In Adsorbent-Amended Hybrid Constructed Wetland, Ishfaqun Nisa

USF Tampa Graduate Theses and Dissertations

Due to their efficiency in removing ammonia nitrogen, Constructed Wetlands (CW) are currently considered a very useful method for on-site leachate treatment. In recent years, the use of adsorbent media in CWs, such as zeolite and biochar, to improve pollutant removal efficiency has been explored and these studies indicate that incorporating zeolite can improve the nitrification process, while the addition of biochar can enhance the denitrification process and the removal of organic compounds. However, studies on mechanistic/process models simulating performance of adsorbent-amended CWs for treating landfill leachate are limited. This study presents simulation results for both unamended and adsorbent-amended hybrid …


Biochar Amended Biological Systems For Enhanced Landfill Leachate And Lignocellulosic Banana Waste Treatment, Xia Yang Nov 2022

Biochar Amended Biological Systems For Enhanced Landfill Leachate And Lignocellulosic Banana Waste Treatment, Xia Yang

USF Tampa Graduate Theses and Dissertations

Biochar is an inexpensive and environmentally friendly carbonaceous pyrolysis byproduct with a high surface area, pore volume, and adsorption capacities for inorganic and organic compounds. The goal of this dissertation is to evaluate the feasibility of biochar application in biological treatment systems for enhanced waste management. Three major objectives guided this research to provide a compressive understanding of biochar enhancement effects on biological treatment systems for contaminant removal, energy recovery, and environmental impacts as well as essential factors influencing biochar production and properties.

In Objective 1 a low-cost hybrid Constructed Wetland (CW) system modified with biochar/zeolite was developed for enhanced …


Modified Biosand Filtration Using Aluminum Hydroxide Filter Media To Enhance Fluoride Removal, Joshelyn Guimaray Jun 2022

Modified Biosand Filtration Using Aluminum Hydroxide Filter Media To Enhance Fluoride Removal, Joshelyn Guimaray

USF Tampa Graduate Theses and Dissertations

There are over 20 countries whose citizens consume groundwater containing high levels of fluoride, including Nigeria, Mexico, India, China, and Ghana, which all have major health crises when it comes to the safety of their drinking water. Minerals like fluorite contain fluoride which is often found in groundwater aquifers. The minerals release fluoride into the groundwater. Per the World Health Organization (WHO) standard, the maximum contaminant limit for fluoride consumption should be less than 1.5 mg/L. Chronic exposure of elevated levels of fluoride can cause people to suffer debilitating health effects, such as dental and skeletal fluorosis. Dental fluorosis causes …


Use Of Biochar And Zeolite For Landfill Leachate Treatment: Experimental Studies And Reuse Potential Assessment, Thanh Thieu Lam Oct 2021

Use Of Biochar And Zeolite For Landfill Leachate Treatment: Experimental Studies And Reuse Potential Assessment, Thanh Thieu Lam

USF Tampa Graduate Theses and Dissertations

Leachate is a highly colored liquid waste product of landfills that contains high concentrations of ammonia nitrogen (NH4+-N), refractory organic matter, and heavy metals. It is commonly disposed to local publicly owned treatment works (POTWs). With these potent characteristics, it interferes with the physical, biological, and chemical treatment processes within POTWs. Sequencing batch biofilm reactors (SBBR) and hybrid subsurface flow constructed wetlands (CW) have been used in the past to treat landfill leachate, but their design and performance can still be optimized. Addition of low-cost adsorbent materials to SBBRs and CWs, such as biochar and zeolite, have the potential to …


Biochar Amended Bioretention Systems For Nutrient And Fecal Indicator Bacteria Removal From Urban And Agricultural Runoffs, Md Yeasir Arif Rahman Jul 2021

Biochar Amended Bioretention Systems For Nutrient And Fecal Indicator Bacteria Removal From Urban And Agricultural Runoffs, Md Yeasir Arif Rahman

USF Tampa Graduate Theses and Dissertations

Excessive nitrogen and fecal indicator bacteria (FIB) in stormwater runoff from urban areas or dairy farm operations impair water bodies resulting algal blooms, gastrointestinal illness, and economic losses. Recent advancements in stormwater management, including low impact development (LID) techniques, have provided engineers with a variety of tools to use in place of traditional catch basins and retention ponds. One promising LID technology for runoff management is bioretention, which consists of a shallow depression containing engineered porous media and vegetation. Prior studies have shown that modified bioretention systems that include an internal water storage zone (IWSZ) to promote denitrification can improve …


Development Of A Numerical Process Model For Adsorbent-Amended Constructed Wetlands, Lillian Mulligan Jun 2021

Development Of A Numerical Process Model For Adsorbent-Amended Constructed Wetlands, Lillian Mulligan

USF Tampa Graduate Theses and Dissertations

There is a need for alternative methods for municipal landfill leachate treatment as the high concentrations of pollutants in leachate interfere with processes at publicly owned treatment works (POTWs). Constructed wetlands (CWs) have been shown to be a sustainable alternative with good removal efficiencies for chemical oxygen demand (COD) and ammonia nitrogen (NH4+). The addition of an adsorbent media, such as zeolite and biochar, to CWs to further enhance removal efficiencies has been investigated in recent years. However, the long-term effects of zeolite and biochar addition to CWs is not well known. A model could be a useful tool to …


Exploring The Potential Of Nutrient Retention And Recycling With Wetlaculture Systems In Ohio With Physical And Landscape Models, Bingbing Jiang Jun 2020

Exploring The Potential Of Nutrient Retention And Recycling With Wetlaculture Systems In Ohio With Physical And Landscape Models, Bingbing Jiang

USF Tampa Graduate Theses and Dissertations

Significant expansion of agricultural land use has been widely recognized for leading to global and regional negative environmental impacts, especially increased eutrophication of surface water systems for the last half-century. The landscape-scale environmental problem of overloading nutrients to lakes and streams by excessive fertilizer use and increased human-caused N-fixation is in urgent need of a sustainable landscape-scale solution. Wetlands have long been considered as an effective way to remove nutrients from surface water. However, the influence of regional seasonality and hydrologic conditions on agricultural runoff treatment wetlands still needs more investigation. A new approach, “wetlaculture,” has recently described as a …


Enhanced Fluoride Removal In Biosand Filters Using Aluminum Oxide Coated Media And Modified Filter Design, Madison Leigh Rice Mar 2020

Enhanced Fluoride Removal In Biosand Filters Using Aluminum Oxide Coated Media And Modified Filter Design, Madison Leigh Rice

USF Tampa Graduate Theses and Dissertations

In 2010, the UN formally stated that access to safe drinking water and sanitation is a human right. Yet, one in three people globally do not have access to safe drinking water. Contaminated drinking water can negatively impact the health of consumers. This is a challenge that disproportionally affects developing regions, where limited access to resources exacerbates the problem. One drinking water contaminant of concern is fluoride. Fluoride is often added in low concentrations to drinking water to enhance consumers’ dental health. However, when water with high concentrations of fluoride is consumed frequently, it can have negative health effects, such …


Enhanced Nitrogen, Organic Matter And Color Removal From Landfill Leachate By Biological Treatment Processes With Biochar And Zeolite, Bisheng Gao Mar 2020

Enhanced Nitrogen, Organic Matter And Color Removal From Landfill Leachate By Biological Treatment Processes With Biochar And Zeolite, Bisheng Gao

USF Tampa Graduate Theses and Dissertations

Leachate percolating through landfills must be collected and properly treated. However, high concentrations of ammonia (NH4+), refractory organic matter [measured as chemical oxygen demand (COD)], water color and heavy metals in leachate interfere biological processes in conventional wastewater treatment plants. Constructed wetlands (CWs) have been used in the past to treat leachate, but their design and performance has not been properly optimized. In particular, low cost adsorbent materials, such as zeolite and biochar, have the potential to adsorb ammonia and organic compounds, respectively. This increases their retention in the wetland and reduces their toxicity to microorganisms and plants in the …


Bamboo As A Sustainable Engineering Material: Mechanical Properties, Safety Factors, And Experimental Testing, Lorena Sánchez Vivas Jul 2019

Bamboo As A Sustainable Engineering Material: Mechanical Properties, Safety Factors, And Experimental Testing, Lorena Sánchez Vivas

USF Tampa Graduate Theses and Dissertations

With exponential global population growth occurring and associated environmentally destructive consumption of natural resources, alternative materials that are fast growing and sustainable are being sought out to satisfy human needs. One material that is fast growing and sustainable that can be used to meet most basic needs of humans (i.e. shelter, food, tools) is the plant bamboo, of the grass family Poaceae. Bamboo was used in the past by native peoples who lived in the environment where bamboo natively grows (all continents except Europe and Antarctica) with proven success for uses such as shelter, piping, tools, wells, food, fencing, baskets …


Comparison Of Functional Porous Organic Polymers (Pops) And Natural Material Zeolite For Nitrogen Removal And Recovery From Synthetic Urine, Yan Zhang Mar 2018

Comparison Of Functional Porous Organic Polymers (Pops) And Natural Material Zeolite For Nitrogen Removal And Recovery From Synthetic Urine, Yan Zhang

USF Tampa Graduate Theses and Dissertations

Urine comprises around 1% of domestic sewage volume but holds 80% of total nitrogen. Source separation is a sustainable way to wastewater management than traditional way due to low energy cost and preventing certain pollutants into wastewater treatment plants. Currently, removing and recovering nitrogen from source-separated urine has attracted more and more interests. Of them, ion exchange was used for removal and recovery of nitrogen in the form of ammonia from synthetic urine for potential application as a fertilizer in agriculture. No previous research studies were conducted to investigate the removal and recovery of nitrogen from hydrolyzed urine by ion …


Enhancement Of Two Passive Decentralized Biological Nitrogen Removal Systems, Justine L. Stocks Nov 2017

Enhancement Of Two Passive Decentralized Biological Nitrogen Removal Systems, Justine L. Stocks

USF Tampa Graduate Theses and Dissertations

This research evaluates two different Biological Nitrogen Removal (BNR) systems for enhanced nitrogen removal in decentralized wastewater treatment. The first study evaluated the performance of Hybrid Adsorption and Biological Treatment Systems (HABiTS) at the pilot scale with and without stage 1 effluent recirculation. HABiTS is a system developed at the bench scale in our laboratory and was designed for enhanced BNR under transient loading conditions. It consists of two stages; an ion exchange (IX) onto clinoptilolite media coupled with biological nitrification in the aerobic nitrification stage 1 and a Tire-Sulfur Adsorption Denitrification (T-SHAD) system in the anoxic denitrification stage 2. …


The Ability Of An Aquatic Invader To Uptake Nutrients In An Upstream Estuarine Environment: Implications For Reducing The Intensity And Frequency Of Massive Fish Kills In Florida, Melissa L. Kerr May 2017

The Ability Of An Aquatic Invader To Uptake Nutrients In An Upstream Estuarine Environment: Implications For Reducing The Intensity And Frequency Of Massive Fish Kills In Florida, Melissa L. Kerr

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to assess whether nutrient absorption rates by water hyacinths are affected by low-salinity levels. In a controlled experiment, water hyacinths demonstrated the ability to absorb a significant amount of nutrients in low-saline waters while maintaining a slowed growth rate and shortened life span. Nutrient rates were reduced by an average of 36% in ammonia nitrogen and 48% in reactive phosphorus in the tanks of 4.45 parts per thousand (ppt) salinity. Growth rate in the experimental tanks of 4.45 ppt was observed at 33% slower than that of the control. The high salinity comparison tank …