Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 10 of 10

Full-Text Articles in Engineering

Effect Of Ultrasonic Vibration On The Mass Transfer Coefficient In A Sieve Plate Scrubber, Dinora Monroy Melendez Dec 2010

Effect Of Ultrasonic Vibration On The Mass Transfer Coefficient In A Sieve Plate Scrubber, Dinora Monroy Melendez

All Theses

The air pollution technique of wet scrubbers for fumes, mists and suspended dusts as part of a polluted gas stream has been study as well as used for industries for many decades. The sieve tray is the simplest type of these scrubbers. A laboratory-scale single-stage, sieve tray countercurrent wet scrubber has been designed to study the effect of ultrasonic vibrations on the rate of mass transfer. A 20 kHz ultrasound frequency was chosen for a high performance cavitation to enhance the mass transport between the gas and liquid phases. Various perforation diameters and weir heights were employed in order to …


Determination Of Sorption Coefficients For Neptunium, Plutonium, Iodine, And Technetium In Engineered And Natural Systems Under Oxidizing And Reducing Conditions, Michael Lilley Dec 2010

Determination Of Sorption Coefficients For Neptunium, Plutonium, Iodine, And Technetium In Engineered And Natural Systems Under Oxidizing And Reducing Conditions, Michael Lilley

All Theses

Plutonium, neptunium, technetium, and iodine present appreciable risks at nuclear waste disposal sites around the world due to their potential mobility. Sorption of each of these radionuclides is profoundly influenced by oxidation/ reduction reactions. Therefore, the mobility of each radionuclide may be greatly influenced by redox conditions of the natural or engineered system. The primary focus of this study was to determine distribution coefficients (Kd) for each radionuclide for engineered concrete and saltstone systems with varying amounts of reducing slag (a cement additive to create a reducing environment), and for iodide/iodate in natural sediments. Saltstones are a mixture …


Molecular Characterization Of Enrichment Cultures That Grow On Tetrachloroethene, 1,2 Dichloroethane And Ethylene Dibromide, Hari Shankar Peethambaram Dec 2010

Molecular Characterization Of Enrichment Cultures That Grow On Tetrachloroethene, 1,2 Dichloroethane And Ethylene Dibromide, Hari Shankar Peethambaram

All Theses

Halogenated aliphatic hydrocarbons are among the most common contaminants in soil and groundwater found at hazardous waste sites throughout the United States. Among them are tetrachloroethene (PCE), 1,2-dichloroethane (1,2-DCA) and ethylene dibromide (EDB). Organohalide respiration of each compound has been reported. However, considerably less information is known about EDB than PCE and 1,2-DCA, including the yield that occurs during growth with EDB as the sole TEA. The main objective of this project was to determine which types of chlororespiring microbes predominate during growth of enrichment cultures when PCE, 1,2-DCA and EDB served as the TEA, and what their yield is. …


Determining The Global Maximum Biofuel Production Potential Without Conflicting With Food And Feed Consumption, Watcharapol Pumkaew Dec 2010

Determining The Global Maximum Biofuel Production Potential Without Conflicting With Food And Feed Consumption, Watcharapol Pumkaew

All Theses

This study tries to resolve the competition between food and biofuel by balancing the allocation between food and feed areas and biofuel areas for the entire world. The maximum energy production is calculated by determining the theoretical amount of energy that can be grown, once food and feed consumption is taken into account, based on the assumption that unprotected grass and woody lands and forest lands can be converted into cultivated lands. The total optimum land area for biofuel energy, 4,926.49 Mha, consists of corn, rapeseed, sugar beet, sugar cane, and grasses. When considering energy conversion efficiency, the maximum energy …


Modeling Greenhouse Gas Emissions From Conventional Wastewater Treatment Plants In South Carolina, Andrea Hicks Dec 2010

Modeling Greenhouse Gas Emissions From Conventional Wastewater Treatment Plants In South Carolina, Andrea Hicks

All Theses

Wastewater treatment is an essential part of life in the urbanized world. As global climate change becomes a more pressing issue, the greenhouse gas emissions created through wastewater treatment will become a more prominent concern. Tertiary treatment will likely be standard for wastewater treatment plants in the near future, and therefore must be included in a model of greenhouse gas emissions. Also, the geographic location of a WWTP will change the mix of power types (e.g., coal, nuclear, biomass) used to run the plant. Although GHG emissions from the waste sector are small compared to the emissions of the United …


Evaluation Of Tetrachloroethene Dechlorination Under Low Ph Conditions In Microcosms And Enrichment Cultures, Michael Hickey Dec 2010

Evaluation Of Tetrachloroethene Dechlorination Under Low Ph Conditions In Microcosms And Enrichment Cultures, Michael Hickey

All Theses

Chlorinated ethenes are among the most prevalent groundwater contaminants found at hazardous waste sites throughout the United States. Two such sites are the Statesville FCX OU3 Superfund Site in North Carolina and the C-area at the Savannah River Site (SRS) in Aiken, SC. Both sites are contaminated with two of the more common chlorinated ethenes; tetrachloroethene (PCE) and trichloroethene (TCE). Anaerobic biological reductive dechlorination is an increasingly common treatment option. There are two main concerns as to the feasibility of this approach. The first is if the microbes are present that are needed for carrying out complete reductive dechlorination of …


The Effects Of Physical Factors On The Adsorption Of Synthetic Organic Compounds By Activated Carbons And Activated Carbon Fibers, Hatice Kose Aug 2010

The Effects Of Physical Factors On The Adsorption Of Synthetic Organic Compounds By Activated Carbons And Activated Carbon Fibers, Hatice Kose

All Theses

Activated carbons (ACs) and activated carbon fibers (ACFs) have been extensively used for the removal of synthetic organic compounds (SOCs) that have been found to be toxic, carcinogenic, mutagenic or teratogenic. Adsorption of these compounds on ACs and ACFs are controlled by both physical factors and chemical interactions, which depend on the characteristics of the adsorbent (surface area, pore size distribution (PSD), and surface chemistry), the nature of the adsorbate (molecular weight and size, functional groups, polarity, solubility), and the condition of the background solution (pH, temperature, presence of competitive solutes, ionic strength). Since there are several mechanisms that can …


Anaerobic Bio-Oxidation Of Vinyl Chloride And Ethene, Anthony Reid Aug 2010

Anaerobic Bio-Oxidation Of Vinyl Chloride And Ethene, Anthony Reid

All Theses

Tetrachloroethene and trichloroethene are among the most prevalent groundwater contaminants found at hazardous waste sites throughout the United States. Since implementing some of the common treatment methods to remediate these hazardous waste sites would exceed hundreds of billions of dollars, there is considerable interest in reducing costs while achieving remediation regulations. Under anaerobic conditions, these compounds can undergo reduction reactions known as reductive dechlorination. This occurs when an electron donor provides the reducing equivalents needed to replace the chlorine atoms with hydrogen atoms. The daughter products from higher chlorinated ethenes are ethene and ethane which can be used to document …


Modeling Phosphate Adsorption For South Carolina Soils, Jesse Cannon May 2010

Modeling Phosphate Adsorption For South Carolina Soils, Jesse Cannon

All Theses

Eroded sediment and the pollutants it transports are problems in water bodies in South Carolina (SC) and the United States as a whole. Current regulations and engineering practice attempt to remedy this problem by trapping sediment according to settling velocity, and thus, particle size. However, relatively little is known about most eroded soils. In most cases, little experimental data are available to describe a soil's ability to adsorb a pollutant of interest. More-effective design tools are necessary if design engineers and regulators are to be successful in reducing the amount of sediment and sediment-bound pollutants in water bodies. This study …


Plutonium - Humic Acid Stability Constant Determination And Subsequent Studies Examining Sorption In The Ternary Pu(Iv) - Humic Acid - Gibbsite System, Trevor Zimmerman May 2010

Plutonium - Humic Acid Stability Constant Determination And Subsequent Studies Examining Sorption In The Ternary Pu(Iv) - Humic Acid - Gibbsite System, Trevor Zimmerman

All Theses

Plutonium has been released to the environment through a variety of intentional and unintentional mechanisms, including atmospheric testing, disposition from weapons manufacturing processes, and subsurface disposal. Therefore, a thorough understanding of the chemical, physical, and biological processes affecting plutonium transport is imperative. It has been shown that humic acid (HA) (a refractory component of natural organic matter (NOM)) can effectively solubilize plutonium (Santschi et al., 2002). Increased solubility may result in enhanced subsurface transport, due to the higher concentration of Pu in the aqueous phase. In contrast, the formation of ternary surface complexes may hinder actinide transport. Solution pH is …