Engineering Commons^™

Preservation Of Methanogenic Cultures To Enhance Anaerobic Digestion, Ujwal H. Bhattad

Dissertations (1934 -)

The use of anaerobic biotechnology is increasing as a sustainable process to treat various organic wastes. Methanogens convert organic COD into CH4 and play the key role to drive thermodynamically unfavorable biochemical fermentation reactions and keep the digestion process steady and efficient. Progressive understanding of anaerobic microbiology with digester functionality may help to develop efficient, customized methanogenic cultures to enhance anaerobic bioprocesses. Preservation of methanogenic cultures via drying would be a cost-effective option for research and practical applications. However, preservation of methanogenic cultures is challenging due to methanogen sensitivity to O2 toxicity and drying, and very limited work is reported …

Relating Methanogen Community Structure And Function In Anaerobic Digesters, Benjamin T.W. Bocher

Dissertations (1934 -)

A deeper understanding of how microbial community structure relates to process function would help improve anaerobic digester design. This dissertation describes both qualitative and quantitative relationships between anaerobic digester function and microbial community structure. Community structure was characterized using banding pattern intensities from denaturing gradient gel electrophoresis (DGGE) for the mcrA gene of methanogenic Archaea. The first project compared a single-stage continuously mixed stirred tank reactor (CSTR) and staging with an acidogenic CSTR followed by a methanogenic CSTR. After seeding with the same biomass, these unique process configurations exhibited different function and qualitatively different methanogen communities. Compared to a single-stage …

Developing Archetypes For Domestic Dwellings:An Irish Case Study, Albert Famuyibo, Aidan Duffy, Paul Strachan

Articles

Stock modelling, based on representative archetypes, is a promising tool for exploring areas for resource and emission reductions in the residential sector. The use of archetypes developed using detailed statistical analysis (multi-linear regression analysis, clustering and descriptive statistics) rather than traditional qualitative techniques allows a more accurate representation of the overall building stock variability in terms of geometric form, constructional materials and operation. This paper presents a methodology for the development of archetypes based on information from literature and a sample of detailed energy-related housing data. The methodology involves a literature review of studies to identify the most important variables …

Estimating Annual Precipitation For The Colorado River Basin Using Oceanic-Atmospheric Oscillations, Ajay Kalra, Sajjad Ahmad

Civil and Environmental Engineering and Construction Faculty Research

Estimating long-lead time precipitation under the stress of increased climatic variability is a challenging task in the field of hydrology. A modified Support Vector Machine (SVM) based framework is proposed to estimate annual precipitation using oceanic-atmospheric oscillations. Oceanic-atmospheric oscillations, consisting of Pacific Decadal Oscillation (PDO), North Atlantic Oscillation (NAO), Atlantic Multidecadal Oscillation (AMO), and El Niño–Southern Oscillation (ENSO) for a period of 1900–2008, are used to generate annual precipitation estimates with a 1 year lead time. The SVM model is applied to 17 climate divisions encompassing the Colorado River Basin in the western United States. The overall results revealed that …

Flexible Urban Drainage Systems In New Land-Use Areas, Jochen Eckart

USF Tampa Graduate Theses and Dissertations

Urban drainage systems are influenced by several future drivers that affect the performance as well as the costs of the systems. The uncertainties associated with future drivers and their impact creates difficulties in designing urban drainage systems sustainably. A review of the different future drivers for urban drainage systems illustrates that no sufficient future predictions for the long operational life spans of the systems are possible. This dissertation contends that to deal with future uncertainties, flexibility in urban drainage systems is necessary.

At present, profound insights about defining, measuring, and generating flexible urban drainage systems do not exist. This research …

Model-Based Approach To Account For The Variation Of Primary Voc Emissions Over Time In The Identification Of Indoor Voc Sources, Kwanghoon Han

Kwanghoon Han

The study objectives were to improve the understanding of the long-term variation of VOC emission chromatograms of building materials and to develop a method to account for this variation in the identification of individual sources of VOC emissions. This is of importance for the application of the source identification method since materials age over time in real indoor environments. The method is based on the mixed air sample measurements containing pollutants from multiple aged materials and the emission signatures of individual new materials determined by PTR-MS. Three emission decay source models were employed and evaluated for their ability to track …

Rainfall Organization And Geomorphologic Controls On The Flood Response Of Mild-Slope Basins In The South Atlantic Region Of Us, Yiwen Mei

Master's Theses

This study uses data from the Tar-River Basin in North Carolina to explore how space-time rainfall variability influences the hydrologic response from observational and modeling perspectives. For understanding the basin scale effect, the Tar-River Basin is divided into four cascade sub-basins ranging from 1106 km² up to 5654 km². The study evaluates the catchments’ response to rainfall for a large number of storm events by computing the event runoff coefficient based on streamflow observations and through simulations from a semi-distributed hydrological model. Comparison of observed to simulated hydrographs from the hydrological model shows that distributed rainfall forcing …

Concentration Effects And Ion Properties Controlling The Fractionation Of Halides During Aerosol Formation, Marcelo I. Guzman, Richa R. Athalye, Jose M. Rodriguez

Chemistry Faculty Publications

During the aerosolization process at the sea surface, halides are incorporated into aerosol droplets, where they may play an important role in tropospheric ozone chemistry. Although this process may significantly contribute to the formation of reactive gas phase molecular halogens, little is known about the environmental factors that control how halides selectively accumulate at the air-water interface. In this study, the production of sea spray aerosol is simulated using electrospray ionization (ESI) of 100 nM equimolar solutions of NaCl, NaBr, NaI, NaNO(2), NaNO(3), NaClO(4), and NaIO(4). The microdroplets generated are analyzed by mass spectrometry to study the comparative enrichment of …

Implementation, Design, And Cost Analysis Of A Concrete Washout System, Omar Adina

BioResource and Agricultural Engineering

With the increase of environmental pollution in today’s world, many strategies and regulations are being enforced. These enforcements come from the state and federal governments, but public awareness is often overlooked. Stormwater regulations here in California have dramatically changed over the last decade, as the topic is investigated more often.

This senior project encompassed the design prototype and cost analysis of a permanent concrete washout station for the BioResource and Agricultural Engineering Department at California Polytechnic State University, San Luis Obispo. The design parameters given were to construct a steel bin for the excess concrete to be dumped into during …

Proteomic Analysis Of 17Β-Estradiol Degradation By Stenotrophomonas Maltophilia, Zhongtian Li

Z Li

Microbial degradation plays a critical role in determining the environmental fate of steroid hormones, such as 17β-estradiol (E2). The molecular mechanisms governing the microbial transformation of E2 and its primary degradation intermediate, estrone (E1), are largely unknown. The objective of this study was to identify metabolism pathways that might be involved in microbial estrogen degradation. To achieve the objective, Stenotrophomonas maltophilia strain ZL1 was used as a model estrogen degrading bacterium and its protein expression level during E2/E1 degradation was studied using quantitative proteomics. During an E2 degradation experiment, strain ZL1 first converted E2 to E1 stoichiometrically. At 16 h …

Using Ground Penetrating Radar Signal Reflection To Model A Highly Transmissive Bedrock Aquifer, Daniel J. Brockmeyer Mr.

Master's Theses

The use of numerical modeling software to characterize groundwater contaminant fate and transport requires an understanding of the distribution of hydraulic properties of the aquifer. As the complexity of this distribution increases, a more sophisticated understanding is required. Modeling contaminant transport in bedrock aquifers requires that the spatial distributions of highly conductive geologic features are characterized along with the hydraulic transmissivities of those features (Shapiro, 2003). The goal of this research is to refine the numerical model of a highly transmissive crystalline aquifer by characterizing the spatial variability of the hydraulic transmissivity using the attenuation of the ground penetrating radar …

College Of Engineering Senior Design Competition Spring 2018, 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 …

Surface Mass Transfer In Large Eddy Simulation (Les) Of Langmuir Turbulence, Cigdem Akan

USF Tampa Graduate Theses and Dissertations

Over the past century the study of gas exchange rates between the atmosphere and the ocean has received increased attention because of concern about the fate of greenhouse gases such as CO₂ released into the atmosphere. Of interest is the oceanic uptake of CO₂ in shallow water coastal regions as biological productivity in these regions is on average about three times larger than in the open ocean. It is well-known that in the absence of breaking surface waves, the water side turbulence controls gas transfer of sparingly soluble gases such as CO₂ from the air to the …

Assessment Of Iron And Manganese Sequestration, Danielle Volpe

Environmental & Water Resources Engineering Masters Projects

For drinking water with low to moderate levels of iron (Fe) and manganese (Mn) (at or somewhat above the SMCL), sequestration is a less expensive treatment alternative compared to metal oxidation and removal. Sequestration complexes Fe and Mn to prevent precipitation and subsequent water quality problems (turbidity, color, staining, etc.). Despite the widespread use of sequestering agents, research has not resulted in a successful method to directly assess the complexation of Mn and Fe. This study was conducted to develop a method for assessing sequestering agent effectiveness and to assess the effectiveness of several phosphate based sequestering agents for several …

Assessment Of Iron And Manganese Sequestration, Danielle Volpe

Environmental & Water Resources Engineering Masters Projects

For drinking water with low to moderate levels of iron (Fe) and manganese (Mn) (at or somewhat above the SMCL), sequestration is a less expensive treatment alternative compared to metal oxidation and removal. Sequestration complexes Fe and Mn to prevent precipitation and subsequent water quality problems (turbidity, color, staining, etc.). Despite the widespread use of sequestering agents, research has not resulted in a successful method to directly assess the complexation of Mn and Fe. This study was conducted to develop a method for assessing sequestering agent effectiveness and to assess the effectiveness of several phosphate based sequestering agents for several …

Hydrologic Reconstructions Using Dendroclimatology, Climate Signals, And Pacific Ocean Sea Surface Temperature Variability, Sallyrose Anderson

Doctoral Dissertations

The Colorado River provides water to over 25 million people. Given the importance of this water supply, it is critical to understand the hydrologic variables in the Colorado River Basin. In this dissertation, I reconstructed hydrologic conditions (soil moisture, snowpack) in the Upper Colorado River Basin (UCRB) and examined different factors that influence water supply in the region (climate oscillations, oceanic-atmospheric variability).

Firstly, I reconstructed soil moisture in the UCRB. Principal components analysis (PCA) and k-Nearest Neighbor (k-NN) techniques were used to regionalize the gridded data. Correlated tree-ring chronologies (TRCs) were used as predictor variables in stepwise linear regression (SLR) …

Hydrology, Soil Erosion And Climate Interactions On Low Compaction Steep-Sloped Reclaimed Sites In The Southern Appalachian Coal Fields, Tennessee, Siavash Hoomehr

Doctoral Dissertations

The use of loose spoil on steep slopes for surface coal mining reclamation sites has been promoted by the US Department of Interior, Office of Surface Mining for the establishment of native forest. Although low-compaction spoils improve tree survival and growth, the erodibility and hydrology of steep slopes may change due to this practice. The purpose of this study was to quantify the erodibility (K factor), and the Curve Number (CN) value for low compaction, steep-sloped (> 20%) reclaimed mine lands in the Appalachian region, USA. This study also investigated the performance of the SEDCAD model in estimating erosion and …

Synergy Of Alum And Chlorine Dioxide For Curbing Disinfection Byproduct Formation Potential At Central Arkansas Water, Corey W. Granderson

Graduate Theses and Dissertations

Central Arkansas Water (CAW), the water utility for Little Rock, AR, draws their source water from Lake Maumelle and Lake Winona. To curb disinfection byproduct (DBP) formation, CAW has begun retrofitting their two plants to use chlorine dioxide as an alternative primary disinfectant followed by free chlorine secondary disinfection in the distribution system. In this study, fluorescence parallel factor (PARAFAC) analysis was combined with free chlorine simulated distribution system (SDS) tests and DBP formation potential (DBPFP) tests to study the benefit of chlorine dioxide primary disinfection (CDPD) with alum coagulation. Of the DBPs screened, trichloromethane (TCM) was formed in highest …

An Environmental Consequence For Dublin Bay Of A Shift From Hydro-Carbon To Other Energy Production Methods, Zeinab Bedri, John O'Sullivan, Michael Bruen

Conference papers

The Liffey Estuary and Dublin Bay, Ireland are of a great recreational and conservational value. Until recently, the Electricity Supply Board (ESB) plant at Poolbeg, Dublin, abstracted dilution water from the estuary for cooling purposes and subsequently discharged this water back to the estuary at temperatures that were sometimes 7-9oC above ambient values. Prior to its discharge to the estuary, the ESB cooling water was mixed with the sewage effluent from Ringsend Treatment Works, creating a warmer and less-saline pollutant plume that remained buoyant on the water surface, adversely effecting water quality. The ESB plant has since closed as part …

Sudden Increase And Regrowth Of Fecal Coliforms And Escherichia Coli In Wastewater Biosolids After High Solids Centrifugation, Gordon G. Araujo

Master’s Theses

Treatment plants that operate either thermophilic or mesophilic anaerobic digesters with centrifugal dewatering processes have consistently observed densities of fecal coliform and Escherichia coli, both indicator bacteria, that decrease during digestion but then increase after dewatering and storage. The increases have been characterized as two separate phenomena to explain this observation: 1) “Sudden Increase,” or SI, which is defined as the increase that occurs immediately after dewatering and 2) “regrowth,” which is defined as an increase during storage of cake samples over a period of hours or days. The SI observation appears to be more prevalent with biosolids that are …

Mathematical Modeling Of Fluid Spills In Hydraulically Fractured Well Sites, Oluwafemi Michael Taiwo

Graduate Theses and Dissertations

Improved drilling technology and favorable energy prices have contributed to the rapid pace at which the exploitation of unconventional natural gas is taking place across the United States. As a natural gas well is being drilled, reserve pits are constructed to hold the drilling fluids and other materials returned from the drilling process. These reserve pits can fail, and when they do, plant and animal life of the surrounding area may be adversely affected. This project develops a screening tool for a suitable location for a reserve pit. This work will be a critical piece of the Infrastructure Placement Analysis …

A Comparison Of 7q10 Low Flow Between Rural And Urban Watersheds In Eastern United States, Saeed Zabet

Masters Theses

Abstract: Increased runoff peaks and volumes from urbanizing watersheds have been well documented where watershed hydrology becomes modified after 10 to 25% of land area is developed. Lowering of baseflow has also been reported to be modified from urbanization; however hydrology thresholds related to percentage of land area developed are not well quantified. In this study, 100 watersheds in eastern USA were investigated to examine the potential effects of urbanization on low flows. The low flow metric chosen for this analysis is the 7Q10. Historical flow records were obtained from the USGS stream gauges, in which a minimum of 10 …

Anticipated Changes In Precipitation Events Over The 21st Century Using Community Climate System Model, Version 4, Scott Tavish Deneale

Masters Theses

Future global daily precipitation data from Community Climate System Model, version 4 (CCSM4) were analyzed to evaluate changes in a variety of precipitation parameters over the 21st century. Multiple ensemble members of 21st century Representative Community Pathways (RCP) radiative scenarios were included in the model to provide an array of potential future climate change results. Multiple ensembles of historic daily precipitation data from CCSM4 were compared with Global Precipitation Climatology Project (GPCP) V1DD daily precipitation data and Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP) monthly precipitation data. Annual average and 95th percentile precipitation values were averaged from 1997-2005 …

Soil Nitrification And Mineralization Rates Along An Elevation Gradient In The Great Smoky Mountains National Park, Christopher James Rolison

Masters Theses

The Great Smoky Mountains National Park (GRSM) is an area sensitive to acid deposition. Although reports indicate there have been reductions of acid deposition in the eastern United States, water quality in streams has not recovered to perceived natural levels. Coupled soil biogeochemical processes of nitrification and nitrogen mineralization can acidify soil water and play a key role in the fate of nitrogen-based acid deposition and observed stream acidification. Characterizing nitrogen decomposition rates at different elevations improves our understanding of the potential effects of acid deposition and soil interactions with acid ions. Soil chemical properties and potential reaction rates for …

Best Management Practices Effectiveness To Reduce Sediment Transport To Morro Bay, Michael J. Randall

Master's Theses

The Morro Bay Watershed, which is located inSan Luis Obispo County,California, covers more than 48,000 acres of land and discharges intoMorroBaythrough the Morro Bay National Estuary (MBNE). The Chorro Creek Subwatershed consists of approximately 30,000 acres of the overall watershed. The MBNE provides an ecosystem that supports a variety of wildlife from the common sea gull to the endangered sea otter. The estuary is also home to over 200 species of birds. The operational waterfront of theMorroBayHarborwas and continues to be a strong supporter to the local economy of the City of Morro Bay. Numerous studies were conducted since the …

Assessing Ongoing Sources And Fate Of Dissolved Polychlorinated Biphenyls (Pcbs) In A Stream, Viet Dang

All Dissertations

Polychlorinated biphenyls (pcbs) contamination remains a concern due to their persistence and the risk to human health associated with them. Once released into the environment, these substances are mainly associated with sediment particles and sediment organic carbon matter. They bioaccumulate in organisms via contaminated food and only a small faction is desorbed from sediment into the water column. Given the discontinuity of active discharge, pcbs are currently entering the water via groundwater inputs, soil erosion, and/or ongoing leakage from the point source. It is the dissolved form that 1) can be either absorbed by biofilm attached to stream leaves, which …

Nutrient Losses In Runoff From Feedlot Surfaces As Affected By Unconsolidated Surface Materials, John E. Gilley, Jason R. Vogel, Roger A. Eigenberg, David B. Marx, Brian L. Woodbury

Biological Systems Engineering: Papers and Publications

Beef cattle feedlots contain unconsolidated surface materials (loose manure pack) that accumulate during a feeding cycle. The effects of varying amounts of unconsolidated surface materials on runoff nutrient losses are not well understood. The objectives of this study were to (1) compare runoff nutrient losses from feedlot surfaces containing varying amounts of unconsolidated surface materials, (2) determine if differences in runoff nutrient losses exist among rainfall simulation runs, (3) relate runoff nutrient losses to selected feedlot soil characteristics, and (4) identify the effects of varying runoff rate on nutrient loss rates from feedlot surfaces. This study was conducted on 0.75 …

Evaluation Of An Enrichment Culture That Reductively Dechlorinates Γ-Hexachlorocyclohexane, Christina Anderson

All Theses

In a previous study using microcosms from a site contaminated with γ- hexachlorocyclohexane (γ-HCH), rapid anaerobic biodegradation of γ-HCH to benzene and chlorobenzene was observed. Enrichment cultures were developed and subsequently transferred to an anaerobic sulfate-free HEPES buffered medium without loss of γ-HCH dechlorination, thus suggesting γ-HCH undergoes anaerobic biodegradation via chlororespiration. The overall objective of this thesis was to further characterize the enrichment culture.
To do so, one specific objective was to determine the effect of vancomycin on γ-HCH in an enrichment culture grown in a sulfate-free HEPES buffered medium using hydrogen as the electron donor. This objective would …

Application Of Microbial Fuel Cells In A Forested Wetland, Jianing Dai

All Theses

ABSTRACT
Electricity can be generated from forest residues, especially the organic matter from litter fall, in freshwater forested wetland environments with a microbial fuel cell (MFC) system. Electricity generation efficiency was examined for cypress, tupelo, and pine litter extracts, using dual-chamber reactors. The maximum power density generated with cypress extracts was on the level of 320 mW/m2, higher than tupelo (230 mW/m2), and pine (210 mW/m2). The efficacy of cypress extracts was also higher than tupelo and
pine, demonstrating that organic matter from cypress litter is a preferred substrate for electricity generation with MFCs. Meanwhile, low aromaticity of the substrate …

Development Of A Rapid, Solvent Extraction Based Radioanalytical Technique For Monitoring Low-Level Actinide Concentrations In Water Supplies, Joseph Jablonski

All Theses

A rapid radiochemical method for the concentration and subsequent analysis of radionuclides from large volume aqueous samples has been developed by using solvent extraction (SX) followed by quantification via liquid scintillation counting (LSC). This was accomplished using simple radiochemical techniques that resulted in the ability to enact a 200x concentration factor and rapidly detect whether radionuclides are present in dilute aqueous samples. The proposed method has average Minimum Detectable Concentrations (MDC) for 238Pu and 233U of 3.5x10-2 Bq/L and 0.16 Bq/L, which equates to 2.3x10-16 and 2.0x10-12 mol/L, respectively. The MDC value for plutonium is an order of magnitude lower …