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- Keyword
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- Anaerobic Digestion (5)
- Biosolids (4)
- Anaerobic digestion (3)
- Bioaugmentation (3)
- Fatigue (3)
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- Instrumentation (3)
- Wastewater (3)
- Anaerobic (2)
- Arsenic (2)
- Biochar (2)
- Concrete (2)
- Debonding (2)
- E. coli (2)
- Electrocoagulation (2)
- FRP (2)
- Ion Exchange (2)
- Microbial Community (2)
- Microbial community structure (2)
- Micropollutants (2)
- Phosphorus (2)
- Propionate (2)
- Pyrolysis (2)
- Steel (2)
- Triclosan (2)
- Visualization (2)
- Activated Carbon;DBPs;Membrane;Nanofiltration;Porosity;Regeneration (1)
- Advanced Oxidation Processes (1)
- Advanced oxidation (1)
- Ammonia Toxicity (1)
- Ammonia toxicity (1)
- Publication Year
Articles 1 - 30 of 53
Full-Text Articles in Engineering
Antibiotic Resistance In Urban Stormwater Runoff And Green Stormwater Infrastructure, Kassidy N. O'Malley
Antibiotic Resistance In Urban Stormwater Runoff And Green Stormwater Infrastructure, Kassidy N. O'Malley
Dissertations (1934 -)
Antibiotic resistance in the environment poses significant risks to human health, especially through the transmission of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB) via pathways like food and water. Urban stormwater runoff has been identified as a significant contributor to the release and transport of ARGs in the environment but has remained under-researched. This dissertation aimed to address this gap by investigating the fate of ARGs in urban stormwater runoff to guide future stormwater management decisions. Two phases were completed; the first sought to investigate extracellular antibiotic resistance genes (eARGs) in stormwater runoff, and the second focused on quantifying …
The Role Of Membrane Porosity In Ion Removal By Ro/Nf Membranes And Development Of A Regenerable Pac-Loaded Membrane, Yizhi Hou
Dissertations (1934 -)
Reverse osmosis (RO) and nanofiltration (NF) membranes are widely used for water treatment applications. They are charged porous materials, in which size exclusion and charge exclusion work together to dictate solute transport. In this study, membrane porosity was primarily determined by pore size. Thicker, more porous membranes with smaller pores had higher NaCl removal and less permeate water flux. Higher porosity membranes have greater inner pore surface area available to support a greater number of functional groups, thereby rejecting ion flux and increasing ion removal. The Donnan steric pore model (DSPM) was used to determine that the contribution of diffusion …
Monitoring The Performance Of Green Infrastructure: Pervious Pavement And Bioretention, Elizabeth Marie Regier
Monitoring The Performance Of Green Infrastructure: Pervious Pavement And Bioretention, Elizabeth Marie Regier
Master's Theses (2009 -)
Milwaukee, like many other aging cities, struggles with combined sewer overflows, basement backups, and urban stream syndrome. It is increasingly looking to green stormwater infrastructure as a way to alleviate stormwater concerns by treating, retaining, and slowly releasing stormwater near the locations where it falls. However, green stormwater infrastructure varies in its performance, and few studies have been performed in Southeast Wisconsin. Therefore, two bioswales and a pervious pavement installation were monitored for water quantity, total nitrogen, total phosphorus, and total suspended solids. The bioswales were also monitored for dissolved phosphorus. The north bioswale reduced total phosphorus concentrations by a …
Improved Reliability Of Stormwater Detention Basin Performance Through Water Quality Data-Informed Real-Time Control, Sazzad Sharior
Improved Reliability Of Stormwater Detention Basin Performance Through Water Quality Data-Informed Real-Time Control, Sazzad Sharior
Master's Theses (2009 -)
The objective of stormwater detention basins is to capture stormwater runoff to reduce and delay peak flow and to improve the water quality. These objectives can be improved upon by actively controlling the outflow of the basins rather than traditional passive outflow structures. There are studies demonstrating the performance of the active controls that respond in real-time to basin hydraulics, detention time, and rainfall forecasts. We hypothesize that the performance of these active controls can be improved upon by incorporating real-time water quality data streams into the control algorithm. Furthermore, we hypothesize that performance of these active controls also depends …
Impact Of Electrocoagulation Pretreatment On E. Coli Mitigation Using Electrooxidation, William Mcgregor Lynn
Impact Of Electrocoagulation Pretreatment On E. Coli Mitigation Using Electrooxidation, William Mcgregor Lynn
Master's Theses (2009 -)
Small drinking water systems serve approximately 20% of the US population, but they can struggle to comply with the Total Coliform Rule and the Disinfectant and Disinfection Byproduct Rule. Issues with insufficient funds to effectively treat the water and difficulties with the transportation of required chemicals can affect compliance. Electrochemical processes may offer an alternative approach for small water systems as they have demonstrated some advantages over traditional treatments, such as reduced handling and storage of chemicals and cost effectiveness. Sequential electrochemical processes have yet to be tested for the treatment of E. coli in drinking waters. In this study, …
Initial Development Of Advanced, High-Rate Treatment Process For Wet Weather Flows, Paige Elyse Peters
Initial Development Of Advanced, High-Rate Treatment Process For Wet Weather Flows, Paige Elyse Peters
Master's Theses (2009 -)
Billions of gallons of untreated water are discharged into lakes and rivers every year due to combined and sanitary sewer overflows during high-intensity precipitation events. Combined sewer overflows (CSOs) and sanitary sewer overflows (SSOs) pose both environmental and public health risks due to potential human contact with contaminated water. To address the overflow issue, a novel, advanced, high-rate wet weather treatment process was investigated. The high-rate treatment process combined chemically enhanced primary treatment (CEPT) with an advanced oxidation process (AOP) using ozone to rapidly remove total suspended solids (TSS) and chemical oxygen demand (COD), inactive E. coli, and oxidize the …
Uv-Based Advanced Oxidation Of P22 Bacteriophange And E. Coli Bacteria, Vincent Martino
Uv-Based Advanced Oxidation Of P22 Bacteriophange And E. Coli Bacteria, Vincent Martino
Master's Theses (2009 -)
Two novel, sustainable UV-LED advanced oxidation processes (AOPs) were evaluated for their ability to improve inactivation efficacy of P22 bacteriophage and E. coli bacteria. The first objective of this research was to determine the treatment efficacy of P22 bacteriophage and E. coli bacteria using UV-LED at wavelengths of 255, 265, and 285 nm. The UV-LED system demonstrated high inactivation potential for both contaminants at all wavelengths, suggesting it could be a potential alternative to typical low-pressure and medium-pressure mercury-based UV systems. Increased inactivation of both microorganisms was observed with decreasing wavelength (255>265>285 nm). As the peak UV absorbance …
Micropollutant-Free Nutrient Recovery: Adsorption Of Micropollutants On Ion Exchangers And Biosolids-Derived Biochar, Yiran Tong
Dissertations (1934 -)
The presence of excessive nutrients in treated wastewater effluent is a growing concern in terms of water quality and ecological balance. Thus, removal of nutrients is of great interest. Moreover, the removed nutrients can be recovered in forms amenable for agricultural reuse, which yields a sustainable supply of nonrenewable phosphorus that can be used to support global food production. As nutrient recovery gains interest, it is essential that the products be free of harmful contaminants. One class of contaminants of great concern is organic micropollutants. To help address these issues, this study evaluated the fate and impact of micropollutants during …
The Impact Of Phosphorous Species On Dewaterability Of Wastewater Solids, Erik Anderson
The Impact Of Phosphorous Species On Dewaterability Of Wastewater Solids, Erik Anderson
Master's Theses (2009 -)
Phosphorus regulations are causing Water Resource Recovery Facilities (WRRFs) to implement new technologies to remove phosphorus (P) before they discharge liquid effluent. Enhanced Biological Phosphorus Removal (EBPR) is often employed to remove P from water. However, sludges from EBPR plants have shown decreases in dewaterability soon after EBPR was initiated. This decline in dewaterability is not well understood, nor is the best way to improve the dewatering EBPR sludge. Specifically, the role of different P species on sludge dewaterability is not well understood. Several laboratory experiments were conducted at the Marquette University Water Quality Center with the following objectives: i) …
Anaerobic Co-Digestion Of Aqueous Liquid From Biosolids Pyrolysis, Seyedfatemeh Seyedi
Anaerobic Co-Digestion Of Aqueous Liquid From Biosolids Pyrolysis, Seyedfatemeh Seyedi
Master's Theses (2009 -)
Pyrolysis is a process to treat biosolids and recover energy. During pyrolysis, conversion of organic matter to energy-rich products yields biochar, py-gas, and pyrolysis liquids (aqueous phase and non-aqueous bio-oil). The aqueous pyrolysis liquid (APL), is a high-COD liquid with no apparent use that contains polycyclic aromatic hydrocarbons and nitrogen-containing compounds. One potential beneficial use of APL is as a co-digestate to produce more biogas for renewable energy from anaerobic digesters at municipal water resource recovery facilities. Some of the organics in APL may be converted to biomethane via anaerobic digestion under proper conditions. However, some APL organics are known …
Effect Of Low Aeration And Heat Drying On Anaerobic Digester Performance And Microbial Community, Dylan Thomas Friss
Effect Of Low Aeration And Heat Drying On Anaerobic Digester Performance And Microbial Community, Dylan Thomas Friss
Master's Theses (2009 -)
This thesis describes three research projects on anaerobic digestion (AD) that investigated functional differences and relationships between microbial composition and digester function. Both archaeal and bacterial communities were characterized using high throughput (Illumina) sequencing technology with universal 16S rRNA gene primers. In the first project, limited aeration, and limited aeration with an aerotolerant enrichment culture were investigated as possible methods to increase digester functional performance in comparison to a strictly anaerobic control digester. No functional differences were observed at quasi-steady state between the limited aerated digester (LAD), limited aerated anaerobic digester augmented with an aerotolerant enrichment culture (LADE), and strictly …
Pore Resolved Simulations Of Char Particle Gasification, Greg Hingwah Fong
Pore Resolved Simulations Of Char Particle Gasification, Greg Hingwah Fong
Master's Theses (2009 -)
Coal is a significant source of energy in today’s world and many studies have been conducted in order to better understand and optimize its use. To address greenhouse effects associated with coal combustion, cleaner methods for harnessing its energy are being explored. One such method is gasification, a process which converts coal into syngas, a mixture consisting primarily of H2 and CO. Syngas can be used to generate electricity or to produce hydrocarbons that can be used as fuels. To better understand and optimize the process, simulations can be used to study the gasification of individual porous char particles that …
An Improved Method Of Arsenic (Iii) Removal By Reverse Osmosis Membrane, Yizhi Hou
An Improved Method Of Arsenic (Iii) Removal By Reverse Osmosis Membrane, Yizhi Hou
Master's Theses (2009 -)
Arsenic is a Group 1 carcinogen as there is abundant research to support that ingestion of arsenic in drinking water and food can lead to liver, lung, kidney, or bladder cancer in humans. The recommend World Health Organization (WHO) arsenic standard in drinking water is 10 µg/L, while the Environmental Protection Agency's (EPA) Maximum Contaminant Level (MCL) of arsenic in drinking water is 10 µg/L. Globally, at least 40 million people face more than 10 µg/L arsenic contamination in their drinking water. As(III) (trivalent state, such as arsenite), and As(V) (pentavalent state, such as arsenates) are the dominant arsenic forms …
Evaluating The Bond Behavior Between Frp And Grooved Concrete Specimens Using Single Shear Pull Out Test, John Omboko
Evaluating The Bond Behavior Between Frp And Grooved Concrete Specimens Using Single Shear Pull Out Test, John Omboko
Master's Theses (2009 -)
Surface preparation affects the bond behavior between Fiber Reinforcing Polymer (FRP) composite material and concrete. In this research, a special type of surface preparation known as grooving, which involves cutting transverse grooves, is conducted on concrete blocks (specimens) that are categorized as either Unfilled (U) or Filled (F). This idea is to ascertain how the grooves affect the strength of FRP-bonded-concrete specimen. These two categories are then benchmarked to control (C) specimens which do not have grooves on them. Category U specimens only have the epoxy applied on the concrete surface while category F specimens have epoxy applied on both …
Biosolids-Derived Biochar For Micropollutant Removal From Wastewater, Lee Kimbell
Biosolids-Derived Biochar For Micropollutant Removal From Wastewater, Lee Kimbell
Master's Theses (2009 -)
Trace organic compounds including antibiotics, hormones, pharmaceuticals and personal care products are discharged to the environment with liquid and solid effluent streams from water resource recovery facilities. These compounds are referred to as micropollutants, and can have negative impacts in receiving waters. Current wastewater treatment processes are not specifically designed to remove micropollutants, and many of these compounds are recalcitrant to conventional treatment technologies. Triclosan (TCS) was selected as a representative micropollutant in this study due to frequent detection in liquid effluents, residual biosolids, and surface waters. Pyrolysis - the thermochemical decomposition of organic matter at elevated temperatures in the …
Bioaugmentation And Correlating Anaerobic Digester Microbial Community To Process Function, Kaushik Venkiteshwaran
Bioaugmentation And Correlating Anaerobic Digester Microbial Community To Process Function, Kaushik Venkiteshwaran
Dissertations (1934 -)
This dissertation describes two research projects on anaerobic digestion (AD) that investigated the relationship between microbial community structure and digester function. Both archaeal and bacterial communities were characterized using high-throughput (Illumina) sequencing technology with universal 16S rRNA gene primers. In the first project, bioaugmentation using a methanogenic, aerotolerant propionate enrichment culture was investigated as a possible method to increase digester methane production. Nine anaerobic digesters, seeded with different biomass, were operated identically and their quasi steady state function was compared. Before bioaugmentation, different seed biomass resulted in different quasi steady state function, with digesters clustering into high, medium or low …
Cyclic Behavior Of A Hybrid Light Gauge And Hss Mezzanine Structural System, Michael John Kren
Cyclic Behavior Of A Hybrid Light Gauge And Hss Mezzanine Structural System, Michael John Kren
Master's Theses (2009 -)
Cold-formed steel is emerging as an alternative material in the building industry to hot-rolled steel for smaller buildings and indoor structures also called mezzanines. Cyclic testing of a full-scale mezzanine structures composed of cold-formed structural channel beams connected to hollow structural steel (HSS) columns cap plates using wedge expansion anchors at the base plate to generate rotation restraint, is performed in this research. The characteristics of the structure will be explained by displaying full experimental results of structural testing. Unfortunately, limited experimental data outlining the behavior of these structures is available and design criteria is very limited. Thus, there is …
The Role Of Household Antimicrobials In The Proliferation Of Antibiotic Resistance During Anaerobic Digestion, Daniel Elliott Carey
The Role Of Household Antimicrobials In The Proliferation Of Antibiotic Resistance During Anaerobic Digestion, Daniel Elliott Carey
Dissertations (1934 -)
Antimicrobial chemicals in consumer personal care products have been found to increase antibiotic resistance in pure culture studies. Although many studies focus on antibiotic resistance development pertinent to medical scenarios, resistance developed in natural and engineered environments might be significant and has become an emerging concern for human health. This dissertation focuses on the antimicrobial chemicals triclosan and triclocarban. These compounds are distinctly different from antibiotics and are used in products like soaps that are labelled as “antibacterial”. Municipal wastewater treatment plants receive triclocarban and triclosan loads higher than most contaminants of emerging concern because they are frequently used in …
Anaerobic Membrane Bioreactors To Treat Municipal Wastewater At Ambient Temperatures, Matthew D. Seib
Anaerobic Membrane Bioreactors To Treat Municipal Wastewater At Ambient Temperatures, Matthew D. Seib
Dissertations (1934 -)
Anaerobic biotechnology is viewed as a sustainable alternative to aerobic biotechnology for municipal wastewater recovery. However, anaerobic processes have not been successful in cold climates. Past examples have not been able to meet low organic effluent concentrations, or have failed due to biomass washout resulting from low temperature operation and short hydraulic residence time. Recently, the anaerobic membrane bioreactor (AnMBR) has been shown to achieve low effluent organic concentrations and maintain stable anaerobic biomass. However, shortcomings have included high energy demands for membrane operation and poor understanding of microbial community structures within AnMBRs. This dissertation describes efforts to improve AnMBRs …
The Contribution Of Syntrophic Fatty-Acid Degrading Microbial Communities To Anaerobic Digester Function And Stability, Prince Peter Mathai
The Contribution Of Syntrophic Fatty-Acid Degrading Microbial Communities To Anaerobic Digester Function And Stability, Prince Peter Mathai
Dissertations (1934 -)
Anaerobic digestion (AD), the conversion of complex organic matter to methane, occurs through a series of reactions mediated by different guilds of microorganisms. AD process imbalances, such as organic overload or high organic loading rates (OLR), can result in the accumulation of volatile fatty acids (VFA) e.g., propionate, which must be degraded to maintain stable reactor function. VFAs are metabolized by syntrophic fatty-acid degrading bacteria (SFAB) in association with methanogenic archaea (collectively, syntrophic microbial communities, SMC). Despite their indispensable role in AD, little is known about the ecology of SFAB, especially under stressed conditions. To facilitate ecological studies, four quantitative …
A Semantics-Based Approach To Construction Cost Estimating, Mehrdad Niknam
A Semantics-Based Approach To Construction Cost Estimating, Mehrdad Niknam
Dissertations (1934 -)
A construction project requires collaboration of different organizations such as owner, designer, contractor, and resource suppliers. These organizations need to exchange information to improve their teamwork. Understanding the information created in other organizations requires specialized human resources. Construction cost estimating is one of the processes that requires information collected from several sources including a building information model (BIM) created by designers, estimating assembly and work item information maintained by contractors, and construction resource cost information provided by resource suppliers. Currently, it is not easy for computers to integrate the information for construction cost estimating over the Internet. This study discusses …
Municipal Wastewater Anaerobic Treatment With Enhanced Clarification, Kevin Berg
Municipal Wastewater Anaerobic Treatment With Enhanced Clarification, Kevin Berg
Master's Theses (2009 -)
As energy costs rise, water reclamation facilities (WRFs) desire lower cost, easily operated systems to remove BOD5 and suspended solids. WRFs typically utilize an aerobic process called activated sludge to remove biochemical oxygen demand (BOD). BOD, specifically 5 day BOD (BOD5), is used as an indicator of the organic strength of a solution. Anaerobic treatment provides an alternative to activated sludge by removing BOD5, generating biogas containing methane for energy and producing less biomass that requires disposal. Anaerobic treatment functions as an exceptional alternative to activated sludge when packaged as a system with a small footprint that operates at ambient …
Implications Of Heterogeneity In The Shock Wave Propagation Of Dynamically Shocked Materials, Jeffrey W. Lajeunesse
Implications Of Heterogeneity In The Shock Wave Propagation Of Dynamically Shocked Materials, Jeffrey W. Lajeunesse
Master's Theses (2009 -)
The field of shock physics as a whole has only recently begun to pay particular attention to modeling heterogeneous materials under shock loading. These materials are important because of their practicality in terms of creating stronger, more shock resistant materials. To understand why they absorb shock impact energy better than homogeneous materials means that the small-scale processes that occur during the shock loading of these heterogeneous materials needs to be understood. Recent computational experiments, called mesoscale simulations, have shown that explicitly incorporating small-scale heterogeneous features into hydrocode simulations allows the bulk shock response of the heterogeneous material to be observed …
Pyrolysis For Estrogens Removal From Wastewater Solids, Thomas C. Hoffman
Pyrolysis For Estrogens Removal From Wastewater Solids, Thomas C. Hoffman
Master's Theses (2009 -)
Wastewater treatment processes are not designed to remove estrogenic micropollutants and therefore when wastewater biosolids are land applied estrogenic micropollutants are discharged to the environment. Release of estrogenic compounds has deleterious effects on the terrestrial environment. Public concern stemming from micropollutants may reduce the value of biosolids which are important to water resource reclamation facilities (WRRF) as by-products. The objective of this research was to evaluate pyrolysis, the partial decomposition of organic material in an oxygen-deprived system under high temperatures, as a sustainable solution to remove estrogenic compounds from biosolids while producing a useable soil conditioner called biochar. Batch pyrolysis …
Nutrient Recovery From Anaerobic Membrane Bioreactor Permeate Using Ion Exchange, Patrick Mullen
Nutrient Recovery From Anaerobic Membrane Bioreactor Permeate Using Ion Exchange, Patrick Mullen
Master's Theses (2009 -)
Phosphorus is a common element in wastewater streams and traditional treatment processes are often designed remove it to achieve low effluent limits. Such processes often do not often consider the potential value of the nutrient. Currently, production of phosphate fertilizers has dramatically risen causing concern for the depletion of phosphate rock reserves, bringing about exploration into alternative sources of phosphorus for agricultural use. Combining the needs of phosphorus removal from wastewaters and securing alternate sources of the nutrient provide an opportunity for recovery. This project evaluated a nutrient recovery process through ion exchange with beneficial recovery as precipitated struvite using …
Removal Of Trace Heavy Metals From Drinking Water By Electrocoagulation, Joe Heffron
Removal Of Trace Heavy Metals From Drinking Water By Electrocoagulation, Joe Heffron
Master's Theses (2009 -)
Geologic and anthropogenic heavy metals contaminate drinking water for hundreds of millions of people worldwide. Electrocoagulation -- the in situ generation of coagulant by electrolytic oxidation of metal electrodes -- is a century-old process gaining new traction for metal removal from water and wastewater. However, the low conductivity of drinking water and low target contaminant concentrations required for human consumption present challenges for electrocoagulation of drinking water. This study is unique in that it addresses seven different metal contaminants at the trace concentrations of concern to human consumption and investigates the wide range of possible source water matrices. The goal …
Fate Of Micropollutants During Pyrolysis Of Biosolids, John Ross
Fate Of Micropollutants During Pyrolysis Of Biosolids, John Ross
Master's Theses (2009 -)
Approximately 250 tons of organic micropollutants, including pharmaceuticals, antimicrobials, and hormones, are discharged to the environment during land application of wastewater biosolids annually. Reusing wastewater biosolids is vital to the sustainability of wastewater treatment, but current treatment processes do not remove micropollutants from biosolids in an efficient manner. Pyrolysis―the heating of biomass to temperatures between 400 and 800 °C under oxygen-free conditions―was proposed as a biosolids treatment process that could produce a beneficial soil amendment product, biochar, and remove micropollutants. The objective of this research was to determine the effect of pyrolysis temperature and residence time on the removal of …
Failure Mechanisms And Key Parameters Of Frp Debonding From Cracked Concrete Beams, Tayyebeh Mohammadi
Failure Mechanisms And Key Parameters Of Frp Debonding From Cracked Concrete Beams, Tayyebeh Mohammadi
Dissertations (1934 -)
Intermediate crack (IC) induced debonding failure of Fiber Reinforced Polymer (FRP)-strengthened reinforced concrete beams starts at the tip of flexural/shear cracks within the shear span and propagates towards the FRP plate termination. In this study, experimental and numerical programs are performed to characterize and predict the failure mechanisms of IC debonding failure, and identify the key parameters affecting such failure. It is found that the bond-slip relation obtained from the pullout test does not represent the bond-slip relation of the FRP/concrete interface in the FRP-strengthened concrete beams, and it cannot be directly used for predicting the load capacity of the …
Anaerobic Co-Digestion Planning And Research For Green Bay, Wi, Jonathan Kusowski
Anaerobic Co-Digestion Planning And Research For Green Bay, Wi, Jonathan Kusowski
Master's Theses (2009 -)
The aspiration to find an alternative sustainable fuel source is an ever growing concern. Anaerobic digestion might hold the answer to finding an alternative sustainable energy source. Anaerobic digestion does not only provide a renewable resource in the form of biogas, but also stabilizes wastes, preventing large amounts from being landfilled or incinerated. Anaerobic digestion of municipal wastewater sludges can often be improved by the addition of high strength industrial wastes, in a process called co-digestion. High strength industrial wastes provide an additional carbon source for the microbes to utilize and convert into usable biogas. Co-digestion also offers the opportunity …
Ion Exchange Nutrient Recovery From Municipal Wastewater, Allen Williams
Ion Exchange Nutrient Recovery From Municipal Wastewater, Allen Williams
Master's Theses (2009 -)
Nitrogen and phosphorus discharge is regulated due to eutrophication. Typically ammonium-nitrogen is removed through nitrification which requires energy and phosphorus (P) is removed by metal salt addition to precipitate P. A more sustainable approach may be to implement nutrient recovery to form fertilizers. Most nitrogen fertilizer is formed through the energy intensive Haber-Bosch process. Phosphate rock, a limited resource, is mined for P fertilizer. Discharge regulations and the fertilizer production costs provide an economic driver for recovery. The current project used anionic and cationic ion exchange (IX) to concentrate the nutrients with recovery by struvite precipitation. Previous work lacks direct …