Environmental Engineering Commons^™

Factors Affecting Algal Biomass Growth And Cell Wall Destruction, Alicia E. Simosa

LSU New Orleans Theses and Dissertations

Research using microalgae Chlorella vulgaris was conducted in order to determine the maximum CO₂ concentration under which algae can grow, within the emission range from oil and natural gas burning plants (0-20%).

After choosing the optimal CO₂ percentage, pH and alkalinity were determined; and finally, an electrochemical (EC) batch reactor connected to DC current was applied to achieve algae cell annihilation, and therefore, facilitate anaerobic digestion, methane production and energy recovery.

It was determined that algae can grow under 20% CO_2, being 15% CO₂ the most effective (pH of 6.64 and alkalinity of 617.5 mg/L CaCO …

Stability And Redispersion Of Platinum Nanoparticle Suspensions For Attachment To Dyes In Low-Cost Solar Cells, Jeffrey Rothstein

Honors Scholar Theses

The project involves optimizing the synthesis, washing, and redispersion of platinum nanoparticles. The nanoparticles are to be attached to dye molecules where they will act as nanocatalysts to reduce energy losses in low-cost dye-sensitized solar cells. The goal is to develop a process based on a pure or mixed solvent that will maintain a stable dispersion of the nanoparticles without interfering with their ability to bond with the dye molecules in the solar cell.

Hydraulic And Hydrologic Properties Of The Sabine River, Annie L. Bryant

Civil Engineering Theses

The Sabine River is located in Northeast Texas and is home to many threatened and endangered species as well as a growing human population. It is important to understand channel properties and flow characteristics of rivers in order better manage these important natural resources. The Sabine was monitored for hydraulic and hydrological properties as this is a poorly understood river at this point in time.

Hydraulic modeling was conducted to determine channel velocities and shear stresses during different storm frequencies. It was found that velocity and shear stress had a direct relationship at lower velocities. A comparison of existing Geographic …

Lucidpipe™ Power System, Purdue Ect Team

ECT Fact Sheets Archive

In most gravity fed water transmission pipelines, it is desired to reduce excess pressure head to prevent undue strain on a pipeline and lower the incidence of leaks. Normally this is done with pressure reducing valves that essentially burn off this excess pressure as heat. The LucidPipe™ system converts it to low cost electricity thereby removing unwanted pressure and generating energy at the same time - energy that can be put used behind the grid or put back on the grid. The LucidPipe™ system extracts a small percentage of pressure head providing nearly invisible operation allowing water operators to fulfill …

College Of Engineering Senior Design Competition Fall 2016, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

Impact Of Rfid Information-Sharing Coordination Over A Supply Chain With Reverse Logistics, Juan Jose Nativi Nicolau

Open Access Dissertations

Companies have adopted environmental practices such as reverse logistics over the past few decades. However, studies show that aligning partners inside the green supply chain can be a substantial problem. This lack of coordination can increase overall supply chain cost. Information technology such as Radio Frequency Identification (RFID) has the potential to enable decentralized supply chain coordinate their information. Even though there are research that address RFID on traditional supply chain, few researches address how to coordinate RFID information sharing in a green supply chain. We study, through simulation experiments, two types of RFID information-sharing coordination under different configurations related …

Modeling Streambank Erosion On Composite Streambanks On A Watershed Scale, A. R. Mittelstet, D. E. Storm, G. A. Fox, P. M. Allen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Streambanks can be a significant source of sediment and phosphorus to aquatic ecosystems. Although the streambank-erosion routine in the Soil and Water Assessment Tool (SWAT) has improved in recent versions, the recently developed routine in SWAT 2012 has undergone limited testing, and the lack of site or watershed specific streambank data increases the uncertainty in the streambank-erosion predictions. There were two primary objectives of this research: (1) modify and test the 2012 SWAT streambank-erosion routine on composite streambanks, and (2) compare SWAT default and field-measured channel parameters and assess their influence on predicted streambank erosion. Three modifications were made to …

Experimental Evaluation Of Structural Steel Coating Systems, Elias Anis Toubia, Sadra Emami

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Departments of transportation (DOTs) currently use the conventional three-coat system as the predominant choice for the corrosion protection of steel bridge structures. Eliminating one step in the coating process could potentially save time and cost associated with lane closures and traffic control costs. This research paper evaluates several two-coat systems based on the zinc-rich primer and polysiloxane topcoat technology. All samples were conditioned and coated in a state-of-the-art, climate-controlled paint booth, simulating common field ENvironmental CONditions (ENCON) (ENCON 1: 25 °C/50% RH, ENCON 2: 10 °C/40%RH, and ENCON 3: 32°C/80% RH). Accelerated weathering tests were performed on 435 coated samples …

Chlorpyrifos Removal For Wastewater Reuse, Indran Kamalanathan

Chemical Engineering Undergraduate Honors Theses

Approximately 1.2 billion people around the world live in areas of physical water scarcity. This could increase to half of the world’s population by 2030 and could displace 24 to 700 million people unless steps are taken to ensure adequate water supply.¹ Water scarcity is an escalating issue within the United States, specifically in Western inland states with arid climates. This scarcity is encouraging communities to investigate tertiary level municipal wastewater treatment, allowing for reuse of wastewater. Unfortunately, wastewater contains numerous contaminants that are not regulated by the Environmental Protection Agency (EPA) under the Safe Drinking Water Act (SDWA). …

Evaluation Of A Supervisor Training Program For Odot’S Ecodrive Program, Donald M. Truxillo, John Macarthur, Leslie B. Hammer, Talya N. Bauer

TREC Final Reports

Eco-driving consists of using energy-efficient approaches to driving aimed at reducing fuel consumption and, ultimately, CO2 emissions. A previous study found that an EcoDrive informational campaign was effective at increasing the use of eco-driving behaviors, but only when employees perceived that their supervisor supported the program and when they were personally motivated to perform the eco-driving behaviors. In order to build upon the findings of our previous study, the present study focused on increasing the use of eco-driving behaviors through an informational eco-driving campaign combined with supervisor training to support the use of eco-driving practices.

In this study we collected …

Field Emissions Of (Hydro)Chlorofluorocarbons And Methane From A California Landfill, Alexander H. Sohn

Master's Theses

A comprehensive field investigation was conducted at Potrero Hills Landfill (PHL) located in Suisun City, California to quantify emissions of twelve (hydro)chlorofluorocarbons (i.e. F-gases). The specific target constituents for this study included CFC-11, CFC-12, CFC-113, CFC-114, HCFC-21, HCFC-22, HCFC-141b, HCFC-142b, HCFC-151a, HFC-134a, HFC-152a, and HFC-245fa. The majority of the F-gas emission studies have been conducted outside of the United States and very limited field landfill emission data are available in the United States. Because of historical usage of blowing agents in insulation foams including CFC-11, HCFC-142b, HFC-134a, and HFC-245fa, models reported in literature predicted high F-gas emissions from a landfill …

Occurrence And Proliferation Of Antibiotics And Antibiotic Resistance In Wastewater Treatment Plants, Majid Neyestani

UNLV Theses, Dissertations, Professional Papers, and Capstones

Solids retention time (SRT) is one of the most important factors in designing and operating activated sludge systems for biological wastewater treatment. Longer SRTs have been shown to alter the structure and function of microbial communities, thereby leading to improved treatment efficacy with respect to bulk and trace organics, nutrient removal, and membrane fouling. However, research has also shown that longer SRTs lead to increased prevalence of antibiotic resistant bacteria, perhaps due to increased exposure to antibiotics present in influent wastewater. The purpose of this study was to characterize changes in microbial community structure in a laboratory-scale activated sludge system …

Evaluation Of Electron Donors For Perchlorate And Nitrate Biodegradation In Contaminated Groundwater Applications, Mayra Alejandra Sarria Cortes

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the United States, perchlorate contamination has been widely reported, including in Las Vegas, Nevada, where perchlorate has been detected at concentrations of 34.7 mg/kg in vadose zone soil and 0.18-3.7 g/L in groundwater. Once this groundwater reaches the Las Vegas Wash, there is potential for widespread contamination of drinking water sources throughout the Southwest, including in Nevada, Arizona, and California. This issue is becoming increasingly important because even at low perchlorate concentrations, sensitive populations such as infants and pregnant women can be potentially impacted due to perchlorate’s ability to hinder iodine uptake into the thyroid glands, which leads to …

Characterization And Delineation Of Karst Geohazards Along Rm652 Using Electrical Resistivity Tomography, Culberson County, Texas, Adam F. Majzoub

Electronic Theses and Dissertations

The Delaware Basin of West Texas and southeastern New Mexico is the major western subdivision of the Permian Basin and a northern extension of the Chihuahuan Desert. The major evaporite unit within the Delaware Basin is the Castile Formation, which consists of gypsum/anhydrite and is highly susceptible to dissolution and karsting. Manifestations of karst within the Castile outcrop are abundant and include sinkholes, subsidence features and caves, both epigene and hypogene in origin.

Land reconnaissance surveys conducted during the summer of 2015 documented abundant karst landforms in close proximity to a major thoroughfare, RM 652, in Culberson County, Texas. 2D …

Determination Of Aqueous Surfactant Solution Surface Tensions With A Surface Tensiometer, Remelisa Esteves, Birce Dikici Ph.D, Matthew Lehman, Qayyum Mazumder, Nonso Onukwuba

Beyond: Undergraduate Research Journal

Surfactant solutions are applicable to engineering systems for cooling equipment for electronics. Surfactants can be added to water to improve heat transfer. An application of using aqueous surfactant solutions can be through microchannel heat sink. Although it is ideal to redesign these systems to reduce heat, it is a costly method. Surfactant solutions at optimal solution concentration can be able to transfer heat quickly and effectively with minimum expense. The surface tension of surfactant solutions is an important parameter for boiling heat transfer and must be taken into consideration. The purpose of this research is to measure surface tension of …

Determination Of Surfactant Solution Viscosities With A Rotational Viscometer, Remelisa Esteves, Nonso Onukwuba, Birce Dikici Ph.D

Beyond: Undergraduate Research Journal

Aqueous surfactant solutions are used in engineering systems for improving boiling heat transfer. The purpose of this research is to determine the viscosities of surfactant solutions and to investigate the effect of composition on viscosity. The results obtained can possibly be used as reference for further study in the effects of surfactant solution viscosities on nucleate boiling. A rotational viscometer was used to determine the viscosities of three surfactant solutions – SLS, EH-14, and SA-9 – of various compositions at room temperature. It was discovered that the viscosities of SLS, EH-14, and SA-9 had a nearly consistent pattern as their …

Quantifying An Aquifer Nitrate Budget And Future Nitrate Discharge Using Field Data From Streambeds And Well Nests, Troy E. Gilmore, David P. Genereux, Kathleen M. Farrell, Helena Mitasova

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Novel groundwater sampling (age, flux, and nitrate) carried out beneath a streambed and in wells was used to estimate (1) the current rate of change of nitrate storage, dS_NO3 /dt, in a contaminated unconfined aquifer, and (2) future [NO₃^–]_FWM (the flow-weighted mean nitrate concentration in groundwater discharge) and f_NO3 (the nitrate flux from aquifer to stream). Estimates of dS_NO3 /dt suggested that at the time of sampling (2013) the nitrate storage in the aquifer was decreasing at an annual rate (mean = –9 mmol/m²yr) equal …

Development Of An Anaerobic-Phototrophic Bioreactor System For Wastewater Treatment, Onur Yilmaz Ozcan

USF Tampa Graduate Theses and Dissertations

For decades, mainstream domestic wastewater treatment has relied on activated sludge processes to remove organic matter, and on biological nutrient removal systems like the A²/O process to remove nutrients. Recently, membrane filtration was also added to the realm of possible technologies for domestic wastewater treatment, with aerobic membrane bioreactors (MBRs) becoming increasingly popular, especially for decentralized, and small to medium scale applications. However, the aerobic activated sludge and MBR processes, which are often combined with biological nutrient removal processes, have high energy costs associated with supplying oxygen to the process, and end up converting the organic matter into …

Effect Of Rainfall Timing And Tillage On The Transport Of Steroidhormones In Runoff From Manure Amended Row Crop Fields, Sagor Biswas, William L. Kranz, Charles A. Shapiro, Daniel D. Snow, Shannon L. Bartelt-Hunt, Mitiku Mamo, David D. Tarkalson, Tian C. Zhang, David P. Shelton, Simon J. Van Donk, Terry L. Mader

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Runoff generated from livestock manure amended row crop fields is one of the major pathways of hormone transport to the aquatic environment. The study determined the effects of manure handling, tillage methods, and rainfall timing on the occurrence and transport of steroid hormones in runoff from the row crop field. Stockpiled and composted manure from hormone treated and untreated animals were applied to test plots and subjected to two rainfall simulation events 30 days apart. During the two rainfall simulation events, detection of any steroid hormone or metabolites was identified in 8–86% of runoff samples from any tillage and manure …

Formation Of Trihalomethanes (Thms) As Disinfection By-Products (Dbps) When Treated Municipal Wastewater Is Disinfected With Sodium Hypochlorite, Helene Kassouf

USF Tampa Graduate Theses and Dissertations

Disinfection is an essential process in the treatment of municipal wastewater before the treated wastewater can be discharged to the environment. Hillsborough County's Northwest Regional Water Reclamation Facility (NWRWRF) in Tampa, Florida, currently uses ultraviolet (UV) light for disinfection. However, this method has proven expensive to implement and maintain, and may not be effective if the light transmission is poor. For these reasons, Hillsborough County is considering switching from UV light to sodium hypochlorite for disinfection. However, hypochlorite (chlorine) disinfection has disadvantages as well, such as the production of disinfection by-products (DBPs) such as trihalomethanes (THM) and haloacetic acids (HAAs), …