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Full-Text Articles in Engineering

Efficient Management Of Nitrogen And Phosphorus At Centralized Water Reclamation Facilities, Helene Kassouf Nov 2021

Efficient Management Of Nitrogen And Phosphorus At Centralized Water Reclamation Facilities, Helene Kassouf

USF Tampa Graduate Theses and Dissertations

A variety of process configurations are employed at municipal water reclamation facilities (WRFs), such as 5-stage Bardenpho, oxidation ditch, modified Ludzack-Ettinger (MLE) process, and sidestream recycle. However, all of these configurations face certain challenges in achieving optimum treatment of nitrogen and phosphorus. In this dissertation, the driving objectives were to: (1) quantitatively assess the fate of nitrogen and phosphorus (mass fluxes) at a treatment facility that employs biological nutrient removal, aerobic digestion, and sidestream recycle, (2) evaluate the performance of a microbial fuel cell (MFC) as a technology to remove nitrogen from sidestreams at a treatment plant that employs that …


Pressure Retarded Osmosis: A Potential Technology For Seawater Desalination Energy Recovery And Concentrate Management, Joshua Benjamin Nov 2021

Pressure Retarded Osmosis: A Potential Technology For Seawater Desalination Energy Recovery And Concentrate Management, Joshua Benjamin

USF Tampa Graduate Theses and Dissertations

Currently, a significant challenge with reverse osmosis-based desalination is reducing the energy consumption and environmental impacts of the process. This project analyzed the viability of using pressure-retarded osmosis (PRO) for energy recovery in seawater desalination facilities using brine concentrate (the draw solution) and other water sources (the feed solution) such as wastewater effluent. The primary goal of this project is to decrease the cost and overall energy consumption of seawater desalination through PRO-based energy recovery. Process modeling, statistical and sensitivity analysis, energy and cost analysis, geospatial and GIS analysis, laboratory-scale testing, water quality analysis, SEM-EDS microscopy, computational fluid dynamics (CFD), …


Shortcut Nitrogen Removal In Photo-Sequencing Batch Reactor, Experiments, Dynamic Model And Full-Scale Design, Sahand Iman Shayan Nov 2021

Shortcut Nitrogen Removal In Photo-Sequencing Batch Reactor, Experiments, Dynamic Model And Full-Scale Design, Sahand Iman Shayan

USF Tampa Graduate Theses and Dissertations

Nitrogen is one of the essential elements for life; however, inefficient use of nitrogen creates major environmental problems. Nitrogen-rich streams from urban areas, farms, and wastewater treatment plants (WWTPs) lead to surface and groundwater contamination, resulting in eutrophication, hypoxia, and notable environmental, public health and economic damage. Ammonia is a form of nitrogen that can be created during industrial or biological nitrogen fixation or decomposition of biomass. Anaerobic digesters (ADs) in WWTP generate biogas from collected sludge from primary and secondary clarifiers to achieve energy recovery in the plant. However, sidestream effluent from dewatering AD sludge contains high concentrations of …


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 …


Sanitation Marketing In Uganda: The Impact Of Gender On Participation And Outcomes, Elizabeth Vicario Oct 2021

Sanitation Marketing In Uganda: The Impact Of Gender On Participation And Outcomes, Elizabeth Vicario

USF Tampa Graduate Theses and Dissertations

Uganda aims to reach universal access to basic sanitation under Sustainable Development Goal #6, but achieving this target by 2030 would require doubling the annual rate of progress. Women are disproportionately affected by poor sanitation due to their health needs and risk of facing violence, but they have historically been excluded from sanitation planning. Low household demand and poor service delivery have stalled progress in Uganda. Market-based sanitation (MBS) is a novel method of developing a sanitation market through stimulating demand and supporting a competitive atmosphere for product and service providers. This research studies the sanitation marketing activities implemented by …


Community Assessment Of Water Perceptions And Household Point-Of-Use Treatment Methods In Madagascar, Isabella Rose Silverman Oct 2021

Community Assessment Of Water Perceptions And Household Point-Of-Use Treatment Methods In Madagascar, Isabella Rose Silverman

USF Tampa Graduate Theses and Dissertations

One in four people around the world do not have access to safe drinking water, which means that two billion people globally lack access. In high-income countries, 0.02% of yearly deaths are attributed to unsafe water sources; however, an alarming 10.6% of deaths occur in Madagascar, for the same reason.

To achieve Sustainable Development Goal 6: Ensure access to water and sanitation for all, a collaboration between public health and engineering is critical. Within the public health sector, social marketing is commonly utilized to address a problem by using commercial marketing principles to change behavior for the good of society. …


Laboratory Examination Of Lead Weights Harvested From Pitcher Pumps In Eastern Madagascar, Madelyn Wilson Oct 2021

Laboratory Examination Of Lead Weights Harvested From Pitcher Pumps In Eastern Madagascar, Madelyn Wilson

USF Tampa Graduate Theses and Dissertations

Previous sampling campaigns in Tamatave, Madagascar, conducted by the University of South Florida (USF) have identified lead contamination in drinking water sourced from self-supply pitcher pumps. The pitcher pump piston and foot valves were identified as the primary source of lead contamination since they are often manufactured from recycled lead acid batteries. The previous field sampling technique consisted of collecting an aliquot of a 10-15-liter composite sample from the pitcher pump for dissolved lead analysis; however, this technique (1) neglects the contribution of particulate lead, (2) does not properly account for the effects of water stagnation inside the pitcher pump …


Effects Of Nitrate On Arsenic Mobilization During Aquifer Storage And Recovery, Hania Hawasli Oct 2021

Effects Of Nitrate On Arsenic Mobilization During Aquifer Storage And Recovery, Hania Hawasli

USF Tampa Graduate Theses and Dissertations

Aquifer storage and recovery technology is used to sustain water resources and to prevent saltwater intrusion. The injected water can come from various resources, including treated wastewater. In pilot ASR studies in the Tampa Bay region, researchers found high As concentrations in the recovered water from the oxidation of the arsenopyrite that is embedded in the aquifers. The presence of dissolved O2 in the injected water is a major factor in the arsenopyrite oxidation during ASR, however the effects of NO3- on the arsenopyrite has not been studied yet. This is an important knowledge gap because injected water may contain …


Computational Fluid Dynamics (Cfd) Analysis Of The Hydraulic Performance And Bio-Kinetics In A Full-Scale Oxidation Ditch, Kiesha C. Pierre Jul 2021

Computational Fluid Dynamics (Cfd) Analysis Of The Hydraulic Performance And Bio-Kinetics In A Full-Scale Oxidation Ditch, Kiesha C. Pierre

USF Tampa Graduate Theses and Dissertations

An oxidation ditch is a biological wastewater treatment unit process where microorganisms are utilized to transform organic matter, and nitrogen from wastewater to meet the desirable effluent concentrations. Mechanical aerators are part of these biological reactors facilitating oxygen transfer for the aerobic microorganisms, while agitating and circulating the phase constituents within the ditch. Modeling the performance of an oxidation ditch involves combining hydrodynamics, oxygen mass transfer, and bio-kinetics and is one of the grand challenges that is of paramount importance in optimization of design and operations of these facilities in an energy efficient way while meeting the targeted effluent concentrations. …


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 …


Sustainability Assessment Of A Pressure Retarded Osmosis System, Samar Al Mashrafi Jun 2021

Sustainability Assessment Of A Pressure Retarded Osmosis System, Samar Al Mashrafi

USF Tampa Graduate Theses and Dissertations

Desalination has the potential to provide a stable supply of clean fresh water and meet the increasing water demands; however, this process does come with a few challenges such as high energy consumption, high energy cost, and a discharge of a highly concentrated brine. Pressure retarded osmosis (PRO) is a technology that could work as an efficient energy recovery technology for desalination since it can significantly reduce the energy consumption and dilute the brine before discharge. Studies have assessed the economic feasibility of PRO systems; however, these studies have not addressed the environmental sustainability of the systems. Thus, there is …


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 …


Leaf Cutter Ant Nest Soil Cement Stabilized Earthen Bricks: Materials And Methods For Engineering Field Applications, Faith Malay Jun 2021

Leaf Cutter Ant Nest Soil Cement Stabilized Earthen Bricks: Materials And Methods For Engineering Field Applications, Faith Malay

USF Tampa Graduate Theses and Dissertations

As climate change threatens vulnerable tropical climates and development outpaces resource availability, the need for diverse construction material grows. The United Nations Sustainable Development Goals aim to reduce poverty in all forms. Diversifying construction material works toward reducing indoor air pollution, the eradication of houselessness, encouraging diversification in industry, and supporting small scale industrialization. In the Province of Bocas del Toro in Panama, there is a tenuous connection to the greater industries in the country due to location and existing infrastructure.This research presents a literature review of the historical approaches to the construction and chemistry of cement stabilized earth bricks, …


Chorine Conversion: Biological And Water Quality Impact On Activated Carbon Block Point Of Use Filters, Horace S. Jakpa Jun 2021

Chorine Conversion: Biological And Water Quality Impact On Activated Carbon Block Point Of Use Filters, Horace S. Jakpa

USF Tampa Graduate Theses and Dissertations

Point-of-use (POU) activated carbon (AC) filters are ubiquitous in many U.S. households. AC can reduce concentrations of lead, other heavy metals, and mitigate taste and odor issues. However, AC filters also remove residual disinfectants, thus allowing for the proliferation of microbes in the filter. In chloraminated systems, this can lead to localized, filter-induced nitrification. Most notably, high nitrite and nitrate in drinking water can cause methemoglobinemia (blue baby syndrome) in children under the age of three, raising public health concerns.

As a control measure for nitrification within distribution systems, utilities practice periodic, short-term secondary disinfectant switches from chloramine to free …


Health Risk Assessment Of Local Populations Ingesting Water With Naturally Occurring Arsenic And Fecal Related Contaminants In Lake Atitlan, Guatemala, Marisol Alvarez Jun 2021

Health Risk Assessment Of Local Populations Ingesting Water With Naturally Occurring Arsenic And Fecal Related Contaminants In Lake Atitlan, Guatemala, Marisol Alvarez

USF Tampa Graduate Theses and Dissertations

Lake Atitlan, Guatemala acts as a sink for wastewater discharge and as a source of drinking water. The populations living in the lake basin are primarily indigenous with a large percentage (70%) living in poverty. Wastewater effluent entering the lake poses an immediate health risk to those using it as a drinking-water source. Additionally, the lake is surrounded by three volcanoes and the water has concentrations of naturally occurring arsenic above the recommended reference level of 10 µg/L. Arsenic is acutely poisonous at high concentrations and has carcinogenic and neurological effects when chronically exposed at low concentrations.

The goal of …


Impact Of Grain Morphology On The Temporal Evolution Of Interfacial Area During Multi-Phase Flow In Porous Media, Fizza Zahid Apr 2021

Impact Of Grain Morphology On The Temporal Evolution Of Interfacial Area During Multi-Phase Flow In Porous Media, Fizza Zahid

USF Tampa Graduate Theses and Dissertations

Many environmental issues deal with the movement of immiscible fluids in the subsurface, e.g., cleanup of oil spills and geological carbon dioxide sequestration. Engineers face a constant challenge to improve the efficiency of these processes. This can be facilitated by studying the underlying physics of how fluids flow and interact in these systems.

Traditionally, lab experiments can provide reliable information about fluid architecture in porous medium, such as trapped fluid volumes and contact area between two immiscible fluids (interfacial area). However, these methods can be expensive and tedious. A well designed numerical experiment is not only able to describe fluid …


Assessment Of The Environmental Sustainability Of A Small Water Production Facility In Madagascar, Jesal Patel Mar 2021

Assessment Of The Environmental Sustainability Of A Small Water Production Facility In Madagascar, Jesal Patel

USF Tampa Graduate Theses and Dissertations

Nearly 2.2 billion people around the globe struggle with access to safely managed drinking water (WHO/UNICEF, 2019), however, there have been certain initiatives taken, particularly by means of small water production facilities for enhancing access to basic drinking water services in rural areas. The water production facility, specifically located in the low- and middle-income countries, usually encounter operational difficulties as a result of limited availability of resources and are required to depend on other resourceful countries for goods and services. Although, with limited research done for assessing the environmental sustainability of water facilities in low- and middle-income countries, numerous data …


Understanding The Leaching Mechanism For Lead (Pb) Found In Components Of Locally Manufactured Handpumps In Eastern Madagascar, Nidhi Shah Mar 2021

Understanding The Leaching Mechanism For Lead (Pb) Found In Components Of Locally Manufactured Handpumps In Eastern Madagascar, Nidhi Shah

USF Tampa Graduate Theses and Dissertations

This research sought to determine the lead leaching mechanism impacted by an inorganic scale observed from lead valve weights of the pitcher pump systems used in Tamatave, Madagascar. Based on previous research, these valve weights are considered to be a major source for high lead levels in pump water consumed by the residents. As a part of the study, Raman Spectroscopy, X-ray Fluorescence Spectroscopy (XRF) and Energy Dispersive Spectroscopy with Scanning Electron Microscope (SEM-EDS) were performed to address the objectives of this research. The pump component samples for the analysis were selected based on the amount and visual characteristics of …


Passive Nitrifying Biofilters For Onsite Treatment Of Saline Domestic Wastewater, Daniel Arnulfo Delgado Mar 2021

Passive Nitrifying Biofilters For Onsite Treatment Of Saline Domestic Wastewater, Daniel Arnulfo Delgado

USF Tampa Graduate Theses and Dissertations

The infrastructure to support the growing world population has polluted many water bodies with nitrogen from urban and agricultural runoff and failing wastewater systems, such as improperly sited and maintained septic systems. Septic systems present a low energy and maintenance option to treat domestic wastewater and is a treatment option that can be done far from a centralized grid. This further reduces cost, maintenance, and energy as it reduces the need to build and maintaining sewage piping and the infrastructure to move the water longer distances. However, these systems tend to fail when their upkeep is left to homeowners that …


A Systems Approach For Improving The Performance Of Rural Community-Managed Water Systems Using Siasar: Case Studies In Bolivia And Colombia, Rachel A. Cannon Mar 2021

A Systems Approach For Improving The Performance Of Rural Community-Managed Water Systems Using Siasar: Case Studies In Bolivia And Colombia, Rachel A. Cannon

USF Tampa Graduate Theses and Dissertations

Globally, the focus of environmental engineers and water, sanitation, and hygiene (WASH) professionals in the rural water sector has shifted from building new technology to ensuring long-term functionality of water systems and closing the access gap between urban and rural residents. In Latin America and the Caribbean, the main challenges to ensuring clean water for all rural residents is poor service delivery quality and limited sustainability over time. A common management strategy in the region, and globally, is community-management, where community members manage, operate, and maintain the water system through cost sharing and financial management. The failure of community-managed water …