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Peroxi-Electrocoagulation For Treatment Of Trace Organic Compounds And Natural Organic Matter At Neutral Ph, Donald R. Ryan, Patrick J. Mcnamara, Claire K. Baldus, Yin Wang, Brooke K. Mayer
Peroxi-Electrocoagulation For Treatment Of Trace Organic Compounds And Natural Organic Matter At Neutral Ph, Donald R. Ryan, Patrick J. Mcnamara, Claire K. Baldus, Yin Wang, Brooke K. Mayer
Civil and Environmental Engineering Faculty Research and Publications
Iron-based oxidation technologies can be advantageous for mitigating trace organic compounds (TOrCs) during water and wastewater treatment due to their production of hydroxyl radicals. However, iron-based oxidation often occurs at acidic pH to promote Fenton's reaction, which limits the processes' feasibility for treatment applications. This study focused on utilizing iron-electrocoagulation (EC) paired with ex situ H2O2 addition (peroxi-electrocoagulation [EC:H2O2]) to promote oxidative reactions at neutral pH conditions. The hydroxyl radical probe para-chlorobenzoic acid (pCBA) was used to gauge oxidant activity and serve as a representative TOrC. The impact of water …
Antibiotic Resistance In Urban Stormwater: A Review Of The Dissemination Of Resistance Elements, Their Impact, And Management Opportunities, Kassidy N. O'Malley, Walter M. Mcdonald, Patrick J. Mcnamara
Antibiotic Resistance In Urban Stormwater: A Review Of The Dissemination Of Resistance Elements, Their Impact, And Management Opportunities, Kassidy N. O'Malley, Walter M. Mcdonald, Patrick J. Mcnamara
Civil and Environmental Engineering Faculty Research and Publications
The public health crisis of antibiotic resistance is a growing threat across the world that is only expected to intensify in the coming years. The cycling of antibiotic resistance genes (ARGs) in the environment via urban stormwater runoff is one means by which humans are exposed to resistant bacteria as traditional gray stormwater infrastructure facilitates the transport of resistance elements into water bodies utilized by the public. In this review, existing research on the occurrence of ARGs in urban stormwater runoff is critically reviewed with the goal of determining the role of stormwater in the dissemination and development of antibiotic …
Impact Of Corrosion Inhibitors On Antibiotic Resistance, Metal Resistance, And Microbial Communities In Drinking Water, Lee K. Kimbell, Emily Lou Lamartina, Stan Kohls, Yin Wang, Ryan J. Newton, Patrick J. Mcnamara
Impact Of Corrosion Inhibitors On Antibiotic Resistance, Metal Resistance, And Microbial Communities In Drinking Water, Lee K. Kimbell, Emily Lou Lamartina, Stan Kohls, Yin Wang, Ryan J. Newton, Patrick J. Mcnamara
Civil and Environmental Engineering Faculty Research and Publications
Corrosion inhibitors, including zinc orthophosphate, sodium orthophosphate, and sodium silicate, are commonly used to prevent the corrosion of drinking water infrastructure. Metals such as zinc are known stressors for antibiotic resistance selection, and phosphates can increase microbial growth in drinking water distribution systems (DWDS). Yet, the influence of corrosion inhibitor type on antimicrobial resistance in DWDS is unknown. Here, we show that sodium silicates can decrease antibiotic resistant bacteria (ARB) and antibiotic-resistance genes (ARGs), while zinc orthophosphate increases ARB and ARGs in source water microbial communities. Based on controlled bench-scale studies, zinc orthophosphate addition significantly increased the abundance of ARB …
Impact Of Traffic On Air Pollution In A Mid-Sized Urban City During Covid-19 Lockdowns, Nathan Hay, Otito Onwuzurike, Somesh Roy, Patrick J. Mcnamara, Margaret L. Mcnamara, Walter M. Mcdonald
Impact Of Traffic On Air Pollution In A Mid-Sized Urban City During Covid-19 Lockdowns, Nathan Hay, Otito Onwuzurike, Somesh Roy, Patrick J. Mcnamara, Margaret L. Mcnamara, Walter M. Mcdonald
Civil and Environmental Engineering Faculty Research and Publications
In this study, we evaluated the changes in air pollutant concentrations around Milwaukee, WI, during and after lockdown due to the COVID-19 pandemic for a period of 126 days. Measurements of particulate matter (PM1, PM2.5, and PM10), NH3, H2S, and O3 + NO2, were made on a 74-km route of arterial and highway roads from April to August 2020 using a Sniffer 4D sensor mounted to a vehicle. Traffic volume during measurement periods were estimated from smartphone-based traffic data. From lockdown (March 24, 2020–June 11, 2020) to …
Pyrolysis—A Tool In The Wastewater Solids Handling Portfolio, Not A Silver Bullet: Benefits, Drawbacks, And Future Directions, Patrick J. Mcnamara, Zhongzhe Liu, Yiran Tong, Hari Santha, Lynne Moss, Daniel Zitomer
Pyrolysis—A Tool In The Wastewater Solids Handling Portfolio, Not A Silver Bullet: Benefits, Drawbacks, And Future Directions, Patrick J. Mcnamara, Zhongzhe Liu, Yiran Tong, Hari Santha, Lynne Moss, Daniel Zitomer
Civil and Environmental Engineering Faculty Research and Publications
Pyrolysis is the process whereby carbonaceous materials, such as biosolids, are heated between 400°C and 900°C in the absence of oxygen. Three main products are generated: a solid product called biochar, a py-liquid that consists of aqueous phase and non-aqueous phase liquid, and py-gas. The biochar holds value as a beneficial soil amendment and sequesters carbon. The py-liquid is potentially hazardous and needs to be dealt with (including potentially reducing it on-site via catalysis or thermal oxidation). Py-gas can be used on-site for energy recovery. Pyrolysis has gained recent interest due to concern over per- and polyfluoroalkyl substances (PFAS) in …
An Inexpensive, Reproducible Method To Quantify Activated Sludge Foaming Potential: Validation Through Lab-Scale Studies And Year-Long Full-Scale Sampling Campaign, Grace K. Scarim, Emily Lou Lamartina, Kaushik Venkiteshwaran, Daniel Zitomer, Ryan J. Newton, Patrick J. Mcnamara
An Inexpensive, Reproducible Method To Quantify Activated Sludge Foaming Potential: Validation Through Lab-Scale Studies And Year-Long Full-Scale Sampling Campaign, Grace K. Scarim, Emily Lou Lamartina, Kaushik Venkiteshwaran, Daniel Zitomer, Ryan J. Newton, Patrick J. Mcnamara
Civil and Environmental Engineering Faculty Research and Publications
Activated sludge is a conventional treatment process for biochemical oxygen demand (BOD) and total suspended solids (TSS) removal at water resource recovery facilities (WRRFs). Foaming events are a common operational issue in activated sludge and can lead to decreased treatment efficiency, maintenance issues, and potential environmental health risks. Stable foaming events are caused by biological and chemical drivers (i.e., microbes and surfactants) during the aeration process. However, foaming events are difficult to predict and quantify. We present an inexpensive and easy-to-use method that can be applied at WRRFs to quantify foaming potential. Subsequently, the method was applied over a year-long …