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Full-Text Articles in Engineering

Reverse Osmosis Desalination With Integrated Compressed Air Energy Storage: Conceptual Design And Modeling, Pooja Mahajan Dec 2012

Reverse Osmosis Desalination With Integrated Compressed Air Energy Storage: Conceptual Design And Modeling, Pooja Mahajan

All Theses

Growing fresh water needs have led to an interest in water desalination using reverse osmosis (RO) membranes. Energy consumption has a large share in the expenses incurred to drive a reverse osmosis desalination system. With depleting fossil fuel reserves, tapping renewable sources of energy is a promising alternative to meet the energy requirements. Wind power coupled to an RO desalination system is a potential means of delivering clean water using sustainable energy. This work investigates modeling of a conceptual wind-energy-driven RO desalination system that is made possible because of an air-pressure energy storage mechanism. Bench-scale experiments were performed on an …


Novel Electron Shuttling Compounds, Ramasubramanian Neeraja Dec 2012

Novel Electron Shuttling Compounds, Ramasubramanian Neeraja

All Theses

Electron mediator's usage in remediation technologies might be an excellent alternative to increase the rate of transformation of various contaminants such as nitroamine, polyhalogenated compounds and many others. Employing electron shuttles open up different pathways for the contaminant transformation and the reaction goes to completion at a much faster rate. Anthraquinone-2,6-disulfonate (AQDS) has been known to be a model electron shuttle with good shuttling capacity followed by humic acids. But the necessity for identifying electron shuttles suitable for field applications is important. As remediation technologies will command application of the shuttles on a large scale, tracing shuttles which are cheap, …


Examination Of The Effectiveness Of Bioretention Cells And Porous Paving Practices In Aiken, Sc, Casey Johnson Dec 2012

Examination Of The Effectiveness Of Bioretention Cells And Porous Paving Practices In Aiken, Sc, Casey Johnson

All Theses

This work seeks to quantify the impact and effectiveness of green infrastructure practices, specifically bioretention cells and porous asphalts, for the reduction of peak flow and volume of stormwater that discharges into the headwaters of the Sand River watershed in Aiken, SC. Stormwater runoff flows and volumes were monitored in the upper Sand River watershed that includes the urban Aiken area, along with two nested subwatersheds, prior to, during, and after the construction of the bioretention cells and porous asphalt sites. Flow data from these monitoring stations were analyzed and the data suggested that there was no significant reduction in …


Assessing Anaerobic Bio-Oxidation Of Vinyl Chloride And Ethene, Ademola Bakenne Aug 2012

Assessing Anaerobic Bio-Oxidation Of Vinyl Chloride And Ethene, Ademola Bakenne

All Theses

Perchloroethene (PCE) and trichloroethene (TCE) are two of the most commonly used chlorinated solvents around the world. These compounds and their dechlorination daughter products have become the most prevalent organic contaminants found in a majority of hazardous waste sites in the United States. Since implementation of traditional remediation methods would cost hundreds of billions of dollars, there has been tremendous interest in bioremediation as a low cost alternative to achieving remedial goals. Anaerobic reductive dechlorination is the most prevalent form of bioremediation in most locations. The ultimate daughter products from reductive dechlorination of PCE and TCE are ethene and ethane, …


Evaluation Of Dichloromethane As An Electron Donor For Reductive Dechlorination Of Tetrachloroethene To Ethene, Yogendra Kanitkar Aug 2012

Evaluation Of Dichloromethane As An Electron Donor For Reductive Dechlorination Of Tetrachloroethene To Ethene, Yogendra Kanitkar

All Theses

Tetrachloroethene (PCE) and trichloroethene (TCE) are the predominant contaminants at hazardous waste sites in the United States. Although less prevalent, dichloromethane (DCM) is also found at a number of sites. EPA classifies PCE and DCM as likely to be carcinogenic in humans by all routes of exposure, while TCE is classified as carcinogenic to humans by all routes. At some sites, releases of PCE, TCE and DCM comingle in the groundwater. Field evidence from one such site in California suggests that DCM is used as the electron donor for reductive dechlorination of TCE. Nevertheless, definitive evidence that DCM can serve …


Historical Integration Of Remote Sensing Data: Can Gis Extract Information From Grayscale Aerial Photographs?, Kristina Robertson Aug 2012

Historical Integration Of Remote Sensing Data: Can Gis Extract Information From Grayscale Aerial Photographs?, Kristina Robertson

All Theses

There have been many changes in land management policies of the National Forest system over the past 100 years. Changes in policy related to law, population growth and economics directly cause changes in land cover. Global land cover changes are occurring at such a pace and magnitude that they are affecting Earth system functioning (Lambin et al., 2001). The analysis of land cover changes plays a key role in understanding several environmental phenomena, resulting in a need for objective and comparable land cover maps (Gennaretti et al., 2011). Advances in remote sensing and Geographic Information Systems (GIS) have modernized land-use …


Developing A Greenhouse Gas Emissions Calculation Tool For Water Utilities, Anthony Hampton Johnston Aug 2012

Developing A Greenhouse Gas Emissions Calculation Tool For Water Utilities, Anthony Hampton Johnston

All Theses

The issue of climate change has led to an increased emphasis on sustainable practices in almost every facet of our lives. For water utilities, this has increased scrutiny on energy use. Although traditionally viewed solely in financial terms, energy use is also the primary source of greenhouse gas (GHG) emissions from water utilities. The emerging concern over GHG emissions coincides with potential federal legislation and regulation by the Environmental Protection Agency (EPA). In order for water utilities to determine their GHG emissions, guides and tools must be made readily available. Information to educate water utilities about their GHG emissions is …


Biomass And Lipid Production From Heterotrophic And Mixotrophic Fed-Batch Cultivations Of Microalgae Chlorella Protothecoides Using Glycerol, Shwetha Sivakaminathan Aug 2012

Biomass And Lipid Production From Heterotrophic And Mixotrophic Fed-Batch Cultivations Of Microalgae Chlorella Protothecoides Using Glycerol, Shwetha Sivakaminathan

All Theses

Chlorella protothecoides is a microalga that can grow both photo-autotrophically and/or heterotrophically under different culture and environmental conditions. In this study both the heterotrophic growth and mixotrophic growth have been conducted. The heterotrophic experiments were conducted completely in the dark while the mixotrophic experiments had the dark cycles with periodic light exposure. The aim of the study was to independently understand the effect of each mode on biomass and lipid yields.
For the heterotrophic experiments, glycerol was used as an external organic carbon source while yeast extract was used as the nitrogen source. The carbon and nitrogen source were added …


Functionalized Nanoparticles As Removable Coatings For Reverse Osmosis Membranes, Megan Smith Aug 2012

Functionalized Nanoparticles As Removable Coatings For Reverse Osmosis Membranes, Megan Smith

All Theses

Reverse osmosis (RO) desalination is increasingly used to produce potable water throughout the world. Despite their promising abilities, membrane filtration processes are limited by fouling. Fouling is a broad term for organics, inorganics, colloids and organisms that interact physically, chemically, or biologically with the membrane surface, resulting in reduced flux and shortened membrane lifespan. There is potential to create a snakeskin-like barrier between the membrane and foulants by electrostatically binding a coating material to the membrane that can be released by pH manipulation, removing foulants in the process. The feasibility of using functionalized nanoparticles as removable adsorptive coatings on RO …


Application Of Microbial Fuel Cells In A Forested Wetland, Jianing Dai May 2012

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 May 2012

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 …


Evaluation Of An Enrichment Culture That Reductively Dechlorinates Γ-Hexachlorocyclohexane, Christina Anderson May 2012

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 …