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Christman, Timothy KeaneThe effects of organic acids on the stress-corrosion cracking of type 304 stainless steel in high temperature water /
Doctor of Philosophy, The Ohio State University, 1985, Graduate School

Committee:

Not Provided (Other)

Subjects:

Engineering

Keywords:

Stainless steel;Organic acids;Water chemistry

Shaw, Meaghan ElizabethConcentration-discharge behavior of contaminants in a stream impacted by acid mine drainage
MS, Kent State University, 2018, College of Arts and Sciences / Department of Geology
Acid mine drainage (AMD) is a common byproduct of mining that has severely degraded many streams world-wide. In coal mining, AMD occurs when pyrite contained in coal is exposed to water and air during mining activities and oxidized to release high concentrations of sulfate, metals, and acid into water bodies. Controls on concentration-discharge (CQ) relationships of solutes in AMD-impacted streams remain unclear due to the complicated nature of acid mine drainage systems. For example, streams may receive inputs from multiple sources including runoff, outflow from constructed treatment systems, and abandoned mines that bypass these systems to continue to contaminate the streams. It is important to understand the CQ relationships of contaminants in AMD-impacted streams in order to elucidate contaminant sources and to predict effects on aquatic ecosystems under different flow regimes. Here, we study the CQ behaviors of acid, metals, and sulfate in an AMD-contaminated watershed in northeastern Ohio where a treatment system has been installed to remediate water draining from a mine pool into the stream. The treatment system includes a series of limestone channels and settling ponds designed to increase drainage pH and promote precipitation of Fe- and Mn-oxides. Stream chemistry was measured in samples collected approximately once per day from March through November and hourly during select storm events. Stream flow was measured continuously at the watershed outlet. Contaminant concentrations in the stream generally decreased with increasing stream discharge due to inputs from the treatment system that only occurred at high flow. A decrease in pH from March (~6) through November (~3) was concurrent with a decrease in stream discharge and declining inputs from the treatment system. Correspondingly, AMD-derived contaminants (Fe, Mn, Al) increased in concentration from March through November. These trends reflect mixing of contaminated baseflow and intermittent inputs from the treatment system, indicating that the treatment system is only effective at neutralizing stream acidity and removing metals when flow is present. We determine that constructed treatment systems can act as ephemeral tributaries to the stream and control CQ behavior at the stream outlet.

Committee:

Elizabeth Herndon (Advisor); David Singer (Committee Member); Anne Jefferson (Committee Member)

Subjects:

Geochemistry; Geology

Keywords:

Concentration-discharge; acid mine drainage; water chemistry

Ieamsupapong, SupatMechanisms of Iron Carbonate Formation on Mild Steel in Controlled Water Chemistry Conditions
Doctor of Philosophy (PhD), Ohio University, 2016, Chemical Engineering (Engineering and Technology)
Degradation of metals associated with hydrocarbon production, combustion processes, and carbon capture is a pernicious problem in the energy sector. Consequently, laboratory simulation of CO2-containing aqueous environments is of vital importance for the study of steel corrosion. However, discrepancies between predicted, experimental, and field corrosion rate data in a midrange of operating parameters have been reported. These discoveries necessitate improving the accuracy of corrosion prediction models. Based upon preliminary experiments, iron carbonate formation near its saturation condition was identified as a major factor observed corrosion rate discrepancies. Therefore, it is imperative to conduct a systematic study to gain more understanding of corrosion product layer formation mechanisms in controlled water chemistry conditions. Small scale CO2 corrosion experiments have lacked control of pH and ferrous ion concentration, potentially creating misleading conditions related to the growth of protective iron carbonate (FeCO3). An improved experimental apparatus to study steel corrosion and associated formation of FeCO3 was developed. The design incorporates a flow-through system, enabling control of water chemistry, and newly developed sample holders that eliminate non-uniformity of flow associated with hanging samples as well as centrifugal effects associated with rotating cylinder electrodes. Corrosion experiments were conducted in a conventional glass cell and the newly developed flow-through system. Significantly different corrosion product morphologies were observed in these different systems. In controlled water chemistry conditions, iron carbide (Fe3C) was found to play a crucial role in the development of the corrosion product as it provided a favorable environment for the formation of a FeCO3 layer at the steel surface. Three different kinds of material (X65 with tempered-martensitic microstructure, C1018 with ferritic-pearlitic microstructure, and 99.8% pure iron) were used to confirm the influence of iron carbide on the formation of corrosion products near saturation conditions. It was found that in the absence of iron carbide (Fe3C), pure iron produced no significant FeCO3 formation under the same operating conditions as the tests conducted on mild steels. Environmental parameters relating to the effect of FeCO3 saturation value, solution pH, and temperature on the formation of corrosion product layers were also investigated. Saturation value conferred the strongest effect on FeCO3 layer formation near saturation conditions among the three environmental parameters explored.

Committee:

Srdjan Nesic (Advisor); Rebecca Barlag (Committee Member); Craig Grimes (Committee Member); Marc Singer (Committee Member); Yoon-Seok Choi (Committee Member); David Young (Committee Member)

Subjects:

Chemical Engineering

Keywords:

iron carbonate; mild steel; controlled water chemistry conditions; iron carbide; environmental parameters; FeCO3 saturation value

Mohamed, Mohd FaridWater Chemistry and Corrosion Inhibition in High Pressure CO2 Corrosion of Mild Steel
Master of Science (MS), Ohio University, 2008, Chemistry and Biochemistry (Arts and Sciences)
In the water chemistry part of the present study, the solubility of CO2 in water, solubility of water in CO2 and solution pH were measured at 25°C, 40°C and 60°C at partial pressures of CO2 up to 80 bar. Experiments were set up to validate the water chemistry model for temperatures up to 100°C and pCO2 up to 600 bar, these were conducted in a 20 liter autoclave equipped for solubility and pH measurements. The water chemistry model developed in this study will be incorporated into a corrosion prediction model for high pCO2 environments. In the inhibition part of the present study, two generic corrosion inhibitors were selected: diethylenetriamine imidazoline with and without thiosulfate; these were studied at various concentrations at 70°C and a CO2 partial pressure of 80 bar. The imidazoline-type corrosion inhibitor was labeled K1 and the imidazoline plus thiosulfate was labeled as K4. The experiments were designed to determine the inhibitive effects at particular inhibitor concentrations as well as the effect of thiosulfate. The experiments were conducted in a 2 liter autoclave equipped for electrochemical measurements. Pitting (localized corrosion) was observed at low concentrations of imidazoline-type inhibitor. At 800 parts per million (ppm) and 1500 ppm, corrosion rates were reduced to 0.8 mm/yr and 0.2 mm/yr from the 18 mm/yr uninhibited corrosion rate, respectively. However, these concentrations are beyond the feasible limits in actual field operations. Addition of thiosulfate was shown to confer improved inhibitor performance; a corrosion rate of 0.1 mm/yr can be reached by adding only 400ppm of corrosion inhibitor K4.

Committee:

Jefferey Rack (Advisor); David Young (Advisor); Srdjan Nesic (Committee Member)

Subjects:

Engineering; Materials Science; Organic Chemistry

Keywords:

Water chemistry; high partial pressure carbon dioxide; corrosion; inhibition

Day, Rachel EliseCHEMICAL MEASURES OF THE GREAT MIAMI WATERSHED: A SEASONAL POSITION WITH MIDWEST BIODIVERSITY INSTITUTE
Master of Environmental Science, Miami University, 2014, Environmental Sciences
The following internship report summarizes a six-month position with Midwest Biodiversity Institute which served as a partial fulfillment of a Master of Environmental Science degree for the Institute for the Environment and Sustainability (IES) at Miami University. The position as Chemical Crew Leader was an integral aspect of a bioassessment for the Great Miami Watershed, located in southwest Ohio. My main responsibility consisted of collecting surface water chemistry data from predetermined sampling locations and assisting with the collection of prolonged water column data collection which was used to generate a profile of the water. This data, along with results from fish and macroinvertebrate assemblage assessments, will be submitted to the Metropolitan Sewer District of Greater Cincinnati (MSDGC) to assist in the proper management of wastewater treatment plant effluent into the Great Miami River. The results of the testing will contribute to the integrity of the Great Miami watershed.

Committee:

Donna McCollum, PhD (Advisor); Thomas Crist , PhD (Committee Member); Robbyn Abbitt, M.S. (Committee Member)

Subjects:

Environmental Science

Keywords:

bioassessment; surface water chemistry data; Great Miami watershed; Ohio

Lees, Michael ECorrosion of Brass Meters in Drinking Water: The Influence of Alloy Composition and Water Chemistry on Metal Release and Corrosion Scale
MS, University of Cincinnati, 2017, Arts and Sciences: Geology
Brass plumbing components including meters, fittings and valves are used extensively in drinking water distribution systems. Until recently, most in-line brass components contained toxic lead, many of which are still presently in use. Corrosion of brass components leads to the release of metals to drinking water. The primary factors of brass corrosion in drinking water are temperature, alloy composition and water chemistry. In this thesis, a combination of mathematical modeling, analytical techniques and geochemical modeling were used to better understand what causes corrosion in brass components. A comprehensive model for the release of copper, lead and zinc from brass water meters has been developed. This model provides a framework to evaluate how meter parameters, such as alloy composition and age, influence metal leaching from brass components. When considering brass composition, zinc concentration within the alloy is shown to be the primary factor in copper and zinc release. Brasses with greater than 8 – 9% zinc exhibit more rapid corrosion when compared to brasses with less than 8% zinc. Age was found to have more influence over lead release than alloy composition, with newer meters releasing significantly higher concentrations of lead versus older meters. In addition to the oxidation of metallic surfaces, corrosion scale formation and dissolution also have a significant impact upon metal concentrations within drinking water. Optical microscopy, X-ray diffraction (XRD), Raman spectroscopy, and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX), were used to characterize the morphology and mineralogy of corrosion scale in two sets of residential water meters. The meters, which were in service for up to 40 years, came from two locations with contrasting water chemistries; Seattle, with relatively low alkalinity, hardness and total dissolved solids (TDS), and Cincinnati, which has moderate alkalinity, hardness and TDS. Results showed the copper minerals cuprite and malachite, to be most abundant within the corrosion scale from both sources. Lead minerals were much more prevalent within the Cincinnati meters, as were carbonates (both Cu & Pb). In general, the Cincinnati meters contained more substantial and consistent scale coverage whereas coverage on the Seattle meters was patchier and more localized. Real world use of drinking water systems cycle between flow and periods of stagnation, where water sits quiescently within the system. During stagnation, changes in water chemistry can include metal concentration, solution pH, and oxidation reduction (redox) potential. PHREEQC was utilized to calculate the saturation index (SI) of metallic species with changing water chemistry. The SI values were used to evaluate whether a given mineral will dissolve or precipitate from water during stagnation. These values were compared to the mineralogy identified in the meters to better understand the mechanism of scale development. Changes in redox potential had the most significant effect upon SI values. Minerals present within the scale were found to form under distinctly different conditions suggesting that dissolution and precipitation rates must also be considered.

Committee:

Warren Huff, Ph.D. (Committee Chair); Andrew Czaja, Ph.D. (Committee Member); J Barry Maynard, Ph.D. (Committee Member)

Subjects:

Geochemistry

Keywords:

brass corrosion;corrosion in drinking water;lead leaching;corrosion scale mineralogy;geochemical modeling;water chemistry

Damdinbal, SaruulRelationship between Aqueous and Sediment Chemistry and its Impact on Biological Recovery in Acid Mine Drainage-Impaired Streams: Monday Creek, Sunday Creek, Thomas Fork, Raccoon Creek, and Hewett Fork
Master of Science (MS), Ohio University, 2016, Environmental Studies (Voinovich)
Acid mine drainage, a product from pyrite weathering in coal mining regions, has caused destructive changes in water chemistry, sediment chemistry, and biological communities in streams in southeastern Ohio. This study focused on correlations between water and sediment chemistry and its impact on benthic macroinvertebrates in the coal mined areas of the Leading Creek, Monday Creek, Raccoon Creek, and Sunday Creek that have been impacted by acid mine drainage. Sediment chemistry analysis was completed at 32 sites in addition to historic data analysis of water chemistry, sediment chemistry, and biology. The study results suggest that contaminants including acidity, Al, Fe, and Mn in the water column and sediment metals namely, As, Ca, Cu, Fe, and Mn are the most likely stressors to impede macroinvertebrate recovery.

Committee:

Natalie Kruse Daniels, PhD (Advisor); Dina López , PhD (Committee Member); Anirudh Ruhil, PhD (Committee Member)

Subjects:

Environmental Studies; Water Resource Management

Keywords:

Acid mine drainage; water chemistry; sediment chemistry; biological recovery

Melton, Lisa NicoleThe Effect of Chloride and Sulfate on the Mineralogy and Morphology of Synthetically Precipitated Copper Solids
Master of Science (M.S.), University of Dayton, 2013, Civil Engineering
Since the implementation of the Lead and Copper Rule in 1991, multiple studies have been completed to explain, predict and mitigate the problems of copper corrosion. Water chemistry is a leading factor in initiating corrosion and a number of parameters have been postulated to be responsible, including pH, alkalinity, chloride and sulfate. The purpose of this research is to identify aqueous conditions that support the formation of copper corrosion by-products found in distribution systems. Specifically, this work attempted to understand: 1) the role of aggressive ions, chloride and sulfate, in the formation synthetically precipitated particles; 2) the effect of aging on solubility and morphology; 3) evaluate morphology associated with solids. Precipitation experiments were conducted at pH seven and nine, with varied dissolved inorganic carbon (10, 50 mg C/L), and ratios of chloride and sulfate at 1:1, 5:1 and 1:5. Copper was added as cupric perchlorate solution at a concentration of 15 mg/L. Analysis of solubility, mineralogy, and morphological changes were conducted over three months using induced coupled argon plasma spectrometry, x-ray diffraction and scanning electron microscope. This research generally supports results previously reported in literature: high pH conditions over a range of DIC levels favor the formation of tenorite. High DIC, neutral pH water favors formation of malachite and experience higher solubility levels. The effect of chloride and sulfate was most evident at low pH, low DIC conditions where connellite, langite and an unidentified mineral were formed. The effect of aging was evident through x-ray diffraction as particles transitioned from amorphous to slightly crystalline. This transition was most evident within 28 days of precipitation, which also correlated to a reduction in solubility. Microscopy analysis provided confirmation on the morphology habits associated with tenorite, malachite, connellite and langite. In additional tenorite and malachite were compared to scale from distribution systems and were comparable in surface features, size and habit.

Committee:

Denise Taylor, Ph.D., P.E. (Committee Chair); Kenya Crosson, Ph.D. (Committee Member); Darren Lytle, Ph.D., P.E. (Committee Member)

Subjects:

Civil Engineering

Keywords:

Copper Corrosion, Water Chemistry, Chloride and Sulfate, X-ray Diffraction, Scanning Electron Microscopy

Colwell, Stephanie ReneeCharacterization of Upland/Wetland Community Types: Changes to Flatiron Lake Bog over a 24-Year Period
Master of Science, The Ohio State University, 2009, Natural Resources
Flatiron Lake Bog in NE Ohio is one of the few remaining kettle-hole bogs in the state and is owned by The Nature Conservancy (TNC). In order to help refine the management of this property, three main goals were set to classify and describe Flatiron Lake Bog. The first goal was to classify the vegetation community types within the Flatiron Lake Bog landholding to aid in long-term planning and management of this unique resource. Seven different community types were found: mixed mesophytic forest, beech-oak-red maple forest, oak-hickory forest, aspen stands, mixed swamp, tamarack-hardwood bog, and buttonbush shrub swamp. A diversity of management issues exists in these different community types, including control of invasive species, effects of water level changes using a managed outlet structure, and agricultural runoff from neighboring landowners. The second goal of this study was to determine any changes in vegetation, water chemistry, and adjacent land use over a 24-year period. A study conducted by Kent State in 1984 provided a baseline data set of vegetation and water chemistry for the bog, which was compared to the vegetation and water chemistry currently present to determine any changes with the changing land uses. The final goal of this study was to analyze relationships along the upland-wetland gradient with differing adjacent land uses (forest or agriculture). All of these results will provide a knowledge base to allow TNC to better manage the Flatiron Lake Bog property.

Committee:

Dawn Ferris, PhD (Advisor); P. Charles Goebel, PhD (Committee Member); Donald Eckert, PhD (Committee Member)

Subjects:

Ecology; Environmental Science; Forestry; Freshwater Ecology; Hydrology; Soil Sciences

Keywords:

Flatiron Lake Bog; Bogs; Land Use Changes; Vegetation Changes; Water Chemistry Changes; Vegetation Communities; Wetland Delineation

Anderson, Cody AllenPermeation Sampling of BTEX and Gasoline
Master of Science, University of Akron, 2010, Chemistry
A method for solventless extraction and determination of gasoline components in water has been developed. This method uses silicone polycarbonate permeation membranes to extract the components, and collect them on a Tenax TA adsorbent. Samples were thermally desorbed into a gas chromatograph with flame ionization detection for separation and determination of the components. Time-weighted average (TWA) concentrations were determined by plotting the amount of analyte collected versus the product of concentration and time (ppb•hr). A linear response was seen in the TWA curves for benzene, toluene, ethylbenzene and the three isomers of xylene (BTEX). These components had detection limits from 1.4 ppb for m- and p-xylene to 2.7 ppb for toluene. The effects of temperature and common environmental contaminants were examined. The advantages of this method include being environmentally friendly due to the lack of solvent and having less steps for analysis than many standard methods.

Committee:

James Hardy, PhD (Advisor)

Subjects:

Analytical Chemistry; Chemistry; Environmental Science; Experiments

Keywords:

BTEX; water; chemistry; benzene; toluene; ethylbenzene; xylene; permeation; membrane; GC; gas chromatography; thermal desorption

McGee, Lauren E.Effects of Low-head Dams on Habitat Structure, Carbon and Nitrogen Allocation, and Microbial Activity in Urban Rivers
Master of Science, The Ohio State University, 2008, Environmental Science
My study objective was to assess how low-head dams impact urban riverine structure and function. I hypothesized that lowhead dam reservoirs would be retentive of materials. I conducted this study in five paired reservoir-reference sites in central Ohio during spring, summer, and autumn 2007. Two-factor block ANOVAs were used to assess differences between reservoir and reference reaches. Most hypotheses were confirmed. Reservoirs had slower water velocities, greater water depths, more fine-sized sediment, greater C and N in sediment, and greater rates of denitrification than reference reaches. C and N in waters, however, were similar in reservoirs and reference reaches. Although water velocities were reduced in reservoirs, water flow was not correlated with C and N in sediments. This suggests that reduced water flows in urban rivers may not be strong enough to lead to the removal of materials from water. Urbanization could play a larger role in impacting ecosystem function.

Committee:

Virginie Bouchard, PhD (Advisor); Richard, P. Dick, PhD (Committee Member); Peter C. Smiley, Jr./PhD (Committee Member)

Subjects:

Biogeochemistry; Ecology; Environmental Science; Freshwater Ecology

Keywords:

denitrification; methane; methane oxidation; nitrification; sediment chemistry; water chemistry

Huff, David AllanWater Quality of the Upper Little Miami River Watershed in Ohio: Impacts of Natural and Anthropogenic Processes.
Master of Science (MS), Wright State University, 2015, Earth and Environmental Sciences
Stream water quality is increasingly threatened by expanding anthropogenic activities, mainly through point source discharges and urban and agricultural runoffs of contaminants getting through a water body’s watershed resulting in pollution. Concerns developed as to whether urban or agricultural type activities were causing most water quality impairment issues in the upper Little Miami River watershed in southwest Ohio. Characterizing the upper Little Miami River (LMR) watershed with respect to water chemistry and Land Use/Land Cover (LULC) while evaluating the sources of any higher than expected natural parameter concentrations, with a strong emphasis on the nutrients phosphorus and nitrate, serves as this study’s purpose. Efforts are made to determine the greatest non-point source nutrient contribution by specific LULC type watersheds and compare findings with known point source nutrient contributions. Up to 23 sites were sampled during dry weather conditions covering all seasons except winter, ranging from July 2009 to November 2010. Sampling began near the head works of the upper LMR watershed at LMR mile 102, site #1 and ended with site #23 at LMR mile 51.3. Data obtained from the analysis of these samples has been comparatively graphed, spatially and statistically analyzed, and worked into loading calculations for comparisons to available online data, such as point source information. General water chemistry measurements show trends of specific ion concentrations, such as sodium and chloride, in relation to LULC drainage areas connected to sampled pour points. Nutrients such as phosphorus and nitrate have concentration amounts significantly influenced by non-agricultural anthropogenic activities. Statistical analyses of the generated data support the observed trends through correlation coefficients. Estimated stream/river flows at the sampled sites provide loading value development of specific parameters that further support significant trends and correlations even when at times the site concentration values of specific parameters drop downstream due to dilution by incoming natural waters. Observations of most significance involved the nutrient phosphorus and the salt NaCl, which showed the highest concentrations to be associated with urban type Land Uses/ Land Covers, such as residential, commercial, industrial, transportation, urban grasses, and drainage classes. Further study revealed that Water Reclamation Facilities (WRF) residing within the urban areas, provided the major source of phosphorus. Where WRF discharge loadings could be separated from estimated loadings calculated at the sample sites, though only in a small section of the whole study area, Agricultural as well as Urban Grasses LULC watershed types show to be at least a secondary source of the nutrients phosphorus and nitrate.

Committee:

Songlin Cheng, Ph.D. (Committee Chair); Abinash Agrawal, Ph.D. (Committee Member); Doyle Watts, Ph.D. (Committee Member)

Subjects:

Environmental Education; Environmental Science; Environmental Studies; Geochemistry; Geographic Information Science; Hydrologic Sciences

Keywords:

water quality; water chemistry; river; stream; pollution; LULC; Land Use Land Cover; nitrogen; nitrate; phosphorus; total phosphorus; Little Miami River; Ohio National Scenic River; upper Little Miami River watershed; watershed; delineated sub basins;