Environmental Engineering Commons^™

Optimization Of Demon® Sidestream Treatment And Potential For Anammox Mainstream Bioaugmentation, Andrea Lauren Nifong

Civil & Environmental Engineering Theses & Dissertations

Anaerobically digested sludge dewatering liquors (e.g. centrate) can represent 15-25% of the total kjeldahl nitrogen (TKN) load on a typical municipal waste water treatment plant (WWTP). Sidestream nitrogen removal has been demonstrated to be an effective tool for improving nitrogen removal performance and reliability with a savings in aeration energy, chemicals (supplemental alkalinity and carbon), and sludge production.

Deammonification, partial nitritation by ammonia oxidizing bacteria (AOB) combined with anaerobic ammonium oxidation (AMX or anammox), provides near complete nitrogen removal with a 65% reduction in energy and 100% reduction in supplemental carbon and alkalinity requirements as compared to traditional nitrification-denitrification. The …

Characterization Of Secondary Organic Aerosol Precursors Using Two-Dimensional Gas Chromatography With Time Of Flight Mass Spectrometry (Gc×Gc/Tofms), Melissa Jordan Roskamp

Dissertations and Theses

The oxidation of volatile organic compounds (VOCs) plays a role in both regional and global air quality through the formation of secondary organic aerosols (SOA). More than 1000TgC/yr of non-methane VOCs are emitted from biogenic sources (significantly greater than from anthropogenic sources). Despite this magnitude and potential importance for air quality, the body of knowledge around the identities, quantities and oxidation processes of these compounds is still incomplete (e.g., Goldstein & Galbally, 2007; Robinson et al., 2009). Two-dimensional gas chromatography paired with time-of-flight mass spectrometry (GC×GC/TOFMS) is a powerful analytical technique which is explored here for its role in better …

Rooftop Pv Impacts On Fossil Fuel Electricity Generation And Co2 Emissions In The Pacific Northwest, Daniel Albert Weiland

Dissertations and Theses

This thesis estimates the impacts of rooftop photovoltaic (PV) capacity on electricity generation and CO2 emissions in America's Pacific Northwest. The region's demand for electricity is increasing at the same time that it is attempting to reduce its greenhouse gas emissions. The electricity generated by rooftop PV capacity is expected to displace electricity from fossil fueled electricity generators and reduce CO2 emissions, but when and how much? And how can this region maximize and focus the impacts of additional rooftop PV capacity on CO2 emissions? To answer these questions, an hourly urban rooftop PV generation profile for 2009 was created …

Gloria Slope Approach - Monitoring Plant Community Changes In Mountain Ecosystems, Jarle I. Holten, Sverre Lundemo, Ph.D.

Guest Lectures

The research described in this presentation is part of the Global Observation Research Initiative in Alpine Environments (GLORIA) whose purpose is to establish and maintain a global, long-term observation network in alpine environments.

Despite changes in mountaintop-vegetation due to recent climate change being observed throughout the world, trends are not consistent. Moreover, as plant communities can be impacted by several different factors, it is important to be able to separate what is due to climate change and what is due to e.g. changes in grazing pressure (see additional file below).

A Novel Approach To Flow Estimation In Tidal Rivers, Hamed Moftakhari Rostamkhani, David A. Jay, Stefan A. Talke, Tobias Kukulka, Peter D. Bromirski

Civil and Environmental Engineering Faculty Publications and Presentations

Reliable estimation of river discharge to the ocean from large tidal rivers is vital for water resources management and climate analyses. Due to the difficulties inherent in measuring tidal-river discharge, flow records are often limited in length and/or quality and tidal records often predate discharge records. Tidal theory indicates that tides and river discharge interact through quadratic bed friction, which diminishes and distorts the tidal wave as discharge increases. We use this phenomenon to develop a method of estimating river discharge for time periods with tidal data but no flow record. Employing sequential 32 day harmonic analyses of tidal properties, …

Passive Stormwater Samplers For Sampling Highway Runoff From Bmps: Feasibility Studies, Mitchell R. Klein

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Pollution from highway stormwater runoff has been an increasing area of concern within the environmental field. To respond to the need for reduced contamination within runoff many Best Management Practices (BMPs) have been implemented. One difficult aspect of BMPs is monitoring their effectiveness along with determining effluent concentrations. The current methods for stormwater sampling include sending technicians or installing an auto-sampler to collect either grab or composite samples. These methods become costly, cumbersome and infeasible due to the potentially large amount of BMPs across a region and the irregularity and difficulty of predicting storms. Passive samplers have proven themselves as …

Renovation Of Ammonia Contaminated Produced Water Using Constructed Wetlands, Donald Beebe

All Dissertations

Pilot-scale wetland treatment systems were designed and constructed to evaluate renovation of simulated oilfield produced water contaminated with ammonia (20 mg/L ammonia-N). A process-based pilot-scale constructed wetland was designed to meet specific biogeochemical conditions for conversion of ammonia to nitrogen gas through microbial nitrification and denitrification. The process-based constructed wetland treated the simulated produced water to meet stringent discharge requirements (less than 1.2 mg/L ammonia-N). Clinoptilolite, a zeolite mineral, was evaluated for use in constructed wetlands to increase ammonia sorption and nitrification activity. Clinoptilolite increased wetland ammonia sorption capacity and served as a microbial carrier for nitrifying bacteria when ranges …

Improvement Of Onsite Wastewater Treatment By Use Of Electrically Conductive Carbon Cloth, Christopher Weber

All Theses

The purpose of this research is primarily focused on carbon oxidation in domestic septic systems. Small-scale septic waste reactors utilizing electrically conductive carbon cloth were assessed for improving carbon oxidation and therefore the overall efficiency of on-site wastewater treatment systems.
A bioelectrochemical system was developed to enhance carbon oxidation in septic systems using electrically conductive carbon cloth as an anode/cathode bridge to transfer electrons from strictly anoxic septic wastewater to an oxic system outside of the septic reactor. This 'septic snorkel' (so named since the system 'breathes' via the carbon cloth extends into an aerobic zone) was designed to lower …

Removal Of N-Nitrosodimethylamine And Trihalomethane Precursors With Powdered Activated Carbon, Wilson Beita Sandi

All Theses

N-nitrosodimethylamine (NDMA) has been used commercially in several applications, including the production of liquid rocket fuel, and a variety of foods, but gained more relevance when it was discovered as a drinking water disinfection by-product (DBP) in 1989. NDMA is a probable human carcinogen with 10-6 lifetime cancer risk associated with a drinking water concentration of 0.7 ng/L, and is listed as a priority pollutant in the Code of Federal Regulations; no federal maximum contaminant level has been established for drinking water yet. However, the United States Environmental Protection Agency is planning to make a preliminary regulatory determination in 2013 …

Evaluation Of Broiler Litter Heat Production During Windrowing & Nitrogen Based Gas Emission Mitigation Using Biofilter, Min Lei

Graduate Theses and Dissertations

Ammonia emission from animal feeding operations (AFOs) has negative effects on environment and animals' health. Thus measuring and mitigating ammonia emission from AFOs is important for environmental protection. In chapter I, different ammonia measurements were discussed and a mitigation technology- biofilter was represented.

In-house windrowing of built-up litter has been used by broiler producers to reduce pathogen loads and rejuvenate litter for the next flock. When litter is piled up for an extended period during downtime, heat generated by the litter pile can become a substantial heat source due to the metabolism of microorganisms. In chapter II, heat production rates …

Evaluation Of Anaerobic Biodegradation Of High Concentrations Of Halogenated Methanes, Priya Rachel Jacob

All Theses

Removal of the chlorinated methanes, carbon tetrachloride (CT), chloroform (CF) and dichloromethane (DCM), and the halogenated methane, trichlorofluoromethane (commonly known as CFC-11 or Freon-11) from contaminated soil and groundwater remains challenging. Releases to the environment resulted from historically poor disposal practices, as well as spills and leaks from underground storage tanks. Among these three compounds, CF is considered the benchmark for evaluating the feasibility of bioremediation, due to its typically high level of toxicity towards most anaerobic prokaryotes. However, inhibitory effects of low concentrations of CFC-11 on anaerobes have been reported as well. Bioremediation is an attractive option for clean-up, …

Phosphorus Removal From Ebpr Sludge Dewatering Liquors Using Lanthanum Chloride, Aluminum Sulfate And Ferric Chloride, Michael Strileski

UNLV Theses, Dissertations, Professional Papers, and Capstones

In wastewater treatment, enhanced biological phosphorus removal (EBPR) is becoming an increasingly popular alternative to chemical precipitation (CP) because of its lower costs and reduced sludge production. However, downstream solids handling processes such as digestion, sludge storage and dewatering promote an undesirable release (i.e. secondary release) of polyphosphate that was stored within EBPR sludge. Released phosphate is recycled to the head of the plant with the liquors of sludge dewatering processes. The concentration of phosphate in recycle streams from EBPR systems can be one to two orders of magnitude higher than the influent phosphorus concentration entering the EBPR system. Plants …

Removal Of Arsenic From Simulated Groundwater Using A Pilot-Scale Constructed Wetland Treatment System, Jeffrey Schwindaman

All Theses

A pilot-scale constructed wetland treatment system (CWTS) was designed and built to produce biogeochemical conditions that promoted targeted processes for removal of arsenic from simulated groundwater. Two series were designed to promote co-precipitation and sorption of arsenic with iron oxyhydroxides under oxidizing conditions, and two series were designed to promote precipitation of arsenic sulfide and co-precipitation of arsenic with iron sulfide under reducing conditions. The two major objectives were to (1) assess arsenic removal performance and (2) determine the fate and distribution of arsenic in each series. Results indicate that arsenic removal performance was greater in series designed to promote …

Air Pressure Energy Storage For Reverse Osmosis: Bench-Scale Proof Of Concept, Ying Sun

All Theses

Society faces diminishing access to clean drinking water because of increasing global population and the development of modern industries. At the same time, climate change and other environmental problems caused by the increase in fossil fuel consumption the emphasis on reducing dependency on traditional energy resources in the process of potable water production. To address both problems, a small-scale wind powered reverse osmosis (RO) desalination system with a unique energy storage mechanism was envisioned to provide an energy buffer such that fluctuating and intermittent wind can be utilized. Energy is stored in the form of compressed air in a pressure …

The Extraction Of Acetic Acid From Thermotoga Neapolitana Fermentation Spent Medium Using Fresh/Recovered Aliquat 336 And Produce Cma, Yifan Du

All Theses

To offer an alternative pathway to produce calcium magnesium acetate (CMA) as an environmental friendly deicer to relieve the pressure on fossil fuels demand, a liquid-liquid extraction process was studied. This process includes using Aliquat 336 (tri-n-octylmethylammonium chloride) diluted in kerosene as an organic extractant to extract acetic acid from Thermotoga neapolitana fermentation spent medium, which contained 34 g/L of acetic acid and 10 g/L of NaCl.
The extraction efficiency of Aliquat 336 was studied under several different extraction conditions. The initial pH of the spent medium was adjusted to a pH range of 2.25 to 5.75 with a 0.5 …

Describing Plutonium Contamination Issues In Hanford Soils: Development Of A Thermodynamic Surface Complexation Model, Sarah Herr

All Theses

The development of remediation strategies for long-term site management requires knowledge of an actinide's geochemical behavior. Understanding this behavior can lead to the formation of a subsurface transport model. For example, plutonium mobility in the subsurface environment is significantly influenced by oxidation-reduction and complexation reactions. This work considered the surface-mediated reduction of plutonium, as well as the hydrolysis and carbonate complexation of the actinide.
Evaluating the significance of these reactions required several variable pH batch sorption studies. Experiments incorporated plutonium and neptunium sorption to sediments from the Hanford Nuclear Reservation in Washington State. Two different sediments were examined: coarse-grained and …

Modeling Benefits Of Implementing Low Impact Development Practices Within Forecasted Growth Scenarios Of The Reedy River Watershed, Stephen Taylor

All Theses

For this research, a previously developed comprehensive watershed water quality model for the Reedy River as developed for South Carolina Department of Health and Environmental Control (SCDHEC) and the US Environmental Protection Agency (EPA) as a total maximum daily load (TMDL) assessment tool was used to assess the benefits of using low impact development (LID) designs in future growth of Greenville County, within the Reedy River watershed. The original intent of this model was to provide SCDHEC with a defensible model that could be used to prepare nutrient TMDLs for an area located at Boyd Millpond and the Reedy River …

Navigating The Academic Job Search For Environmental Engineers: Guidance For Job Seekers And Mentors, David A. Ladner, Stephanie C. Bolyard, Defne Apul, Andrew J. Whelton

Publications

Students and postdoctoral associates interested in tenure-track environmental engineering positions have limited resources to aid them. The Student Services Committee (SSC) of the Association of Environmental Engineering and Science Professors (AEESP) organized a workshop to fill some of the need. Newly hired faculty and experienced search committee and department chairs shared information on how to create competitive applications. Students and postdoctoral associates were also provided with individualized feedback on their faculty application packages. Survey data were collected for all participants, and these data are presented in this paper along with tips shared during the workshop and information collected from the …

Triclosan Enriches For Dehalococcoides-Like Chloroflexi In Anaerobic Soil At Environmentally Relevant Concentrations, Patrick J. Mcnamara, Mark J. Krzmarzick

Civil and Environmental Engineering Faculty Research and Publications

Triclosan is an antimicrobial agent that is discharged to soils with land-applied wastewater biosolids, is persistent under anaerobic conditions, and yet its impact on anaerobic microbial communities in soils is largely unknown. We hypothesized that triclosan enriches for Dehalococcoides-like Chloroflexi because these bacteria respire organochlorides and are likely less sensitive, relative to other bacteria, to the antimicrobial effects of triclosan. Triplicate anaerobic soil microcosms were seeded with agricultural soil, which was not previously exposed to triclosan, and were amended with 1 mg kg⁻¹ of triclosan. Triplicate control microcosms did not receive triclosan, and the experiment was run for …

Cereal Grain Combustion In Domestic Boilers, Andrew Keppel, John Finnan, Bernard Rice, Philip Owende, Kevin Macdonnell

Articles

This study compared the combustion characteristics and the combustion behaviour of oats, barley, triticale and wheat to that of wood pellets. Sustained grain combustion in domestic boilers was feasible but problematic, the main impediment being clinker formation with ash agglomeration. Clinker formation was lowest for oats which burned easily with fewer operational problems. Triticale displayed reasonably good combustion characteristics and also ignited easily. In contrast, barley and wheat proved difficult to ignite while barley combustion was prone to self-extinguish. Thermal and combustion efficiency and heat output were considerably higher at a grain moisture content of 15% compared to a moisture …