Engineering Commons^™

Electrochemical Disinfection Of Municipal Wastewater Using Alternating Current, Xavier A. Chavez Reyes

University of New Orleans Theses and Dissertations

This research focused on chlorine-free disinfection of wastewater by complying with today's regulations. The equipment used was a continuous flow electrochemical reactor connected to an alternating current (AC) power supply. The electrodes used were made out of titanium coated with iridium oxide. To determine the inactivation of Escherichia Coli, a bacterial count method based on the USEPA method 1603 was used.

After several experiments it was determined that electrochemical disinfection using AC was not efficient and economic enough to be classified as a viable alternative to chlorine disinfection. It was demonstrated that chlorine can be produced by electrolysis using AC …

Electro-Disinfection Of Municipal Waste Water Using Direct Current, Julio A. Acosta Vega

University of New Orleans Theses and Dissertations

Wastewater treatment has always been a problem to human settlers. Events such as the great stink of London during the summer of 1858 have pushed engineers into developing new technologies to deal with such wastes in effective and safe ways. Research projects like this aim to find ways of improving performance, economics, or environmental friendliness of treatment and disinfection methods.

This thesis deals with the effectiveness, mechanisms of action, by-products and side effects of using DC current to disinfect secondary effluent. It is proposed as an alternative to conventional methods, such as chlorination, which are not always environmentally friendly or …

Wind And Thermal Effects On Ground Mounted Photovoltaic (Pv) Panels, Chowdhury Mohammad Jubayer

Electronic Thesis and Dissertation Repository

A combination of Computational Fluid Dynamics (CFD) simulations and wind tunnel experiments are carried out to investigate the effects of wind on the aerodynamic loading and heat transfer of a ground mounted stand-alone photovoltaic (PV) panel with tilt angle of 25^o in open country atmospheric boundary layer. Several azimuthal wind directions are considered: Southern 0^o, Southwest 45^o, Northwest 135^o and Northern 180^o. Three dimensional Reynolds-Averaged Navier-Stokes (RANS) approaches with an unsteady solver using Shear Stress Transport (SST) k-ω turbulence closure are employed for the CFD simulations, whereas Particle Image Velocimetry (PIV) and …

Applying Probabilistic Methods To The Nato Military Load Classification System For Bridges, Andrew J. Macdonald

Electronic Thesis and Dissertation Repository

Military vehicles frequently use civilian bridges. The loading effects of military vehicles, both wheeled and tracked, are specific and different than those of civilian vehicles in normal traffic. Calibration to determine appropriate load factors for military loading of civilian bridges has not been fully performed and the corresponding levels of safety have not been quantified. This lack of calibration prevents the implementation of limit state design methods for military bridges and the evaluation bridges for military loading. This thesis quantifies probabilistically the single lane traffic load effects on interior girders of simply supported slab-on-girder bridges for three military vehicles in …

Scheduling Of Container Handling Equipment In Marine Container Terminals, Narges Kaveshgar

Theses and Dissertations

To improve the competitiveness of marine container terminals, it is critical to minimize the makespan of a container vessel. The makespan is defined as the latest completion time among all handling tasks of the container vessel. Lower makespan (i.e. lower vessel turn time) can be achieved through better scheduling of the container handling equipment during vessel operations. The scheduling of terminal equipment is an operational problem, and a detailed schedule for each type of equipment operating in the terminal is necessary. Several studies have applied operations research techniques to optimize the processes of equipment in a terminal. This dissertation investigates …

Functionalized Graphitic Nanoreinforcement For Cement Composites, Nima Zohhadi

Theses and Dissertations

Physical and mechanical properties of graphitic nanomaterials, in particular multiwalled carbon nanotubes (MWCNTs) and graphene nano-platelets (GNPs) make them promising candidates for nanoreinforcement of cement composites. The two key challenges associated with the incorporation of MWCNTs and GNPs are to attain uniform dispersion and interfacial bonding within the composite matrix. The effects of three main-stream dispersion techniques (namely, ultrasonication, acid-etching, and surfactant-coating) on the mechanical properties and microstructure of MWCNT- and GNP-cement composites were experimentally studied. Compressive strength tests and different characterization techniques including dynamic light scattering, Raman spectroscopy, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission …

Application Of Various Adsorbents To Remove Micro-Pollutants In Aquatic System, Chanil Jung

Theses and Dissertations

Untreated or insufficiently treated pharmaceuticals and endocrine disrupting compounds (EDCs) as well as heavy metals have influenced the ecosystem and their exposures in the water system have threatened human health; causing cancers and adverse health effect to immune system. While various water treatment techniques have been applied to solve this problem, adsorption has been considered as one of the most efficient and manageable water purification techniques. Advanced analysis methods for aqueous contaminants have improved comprehension, allowing proficiency about the fate of trace leveled emerging contaminants, thus allowed to reveal the adsorption mechanisms of each pollutant. This dissertation focuses on the …

An Engineering Approach For The Design Of Archaeological Reburial Systems, Angel Ari Perez Mejia

Theses and Dissertations

Archaeological sites are a non-renewable resource which is often our only link to the past. However, sites are under constant threat of destruction due to construction activities. Civil engineers and archaeologists must the work together to ensure both the continued survival of archaeological sites while allowing for development to continue. Reburial systems, when properly designed and constructed, allow for the protection of archaeological sites while allowing the continued use of the land. However, because reburial as an intentional conservation technique is relatively modern, practice is fragmented and there are no universally accepted guidelines. Current reburial system design relies on prescriptive …

Numerical Modeling Of Free Surface Flows Using Depth Averaged And 3d Models, Khaled Mamdouh Mohamed Abdo

Theses and Dissertations

The objectives of the research presented in this dissertation are to develop and apply numerical models to study free surface flows under different boundary conditions, bedform geometry and channel configuration. A 2D depth-averaged model is developed by solving the Saint Venant or the shallow water equations using a finite volume method. An existing 3D model, developed in-house, that solves the Reynoldsaveraged Navier-Stokes equations and conservation equations for suspended sediment and conservative species is adapted for free surface flows by solving the volume of fluid (VOF) equation using a compressive interface capturing scheme for arbitrary meshes, CICSAM. The depth-averaged or shallow …

Context-Sensitive Seismic Strengthening And Repair Of Substandard Confined Masonry, Rahim Ghorbani

Theses and Dissertations

Confined masonry (CM) is a construction system consisting of load-bearing masonry panels that are confined with cast-in-place reinforced concrete tie columns and beams. Due to satisfactory seismic performance, CM has become the predominant low-rise residential construction system in several areas around the world. However, in developing regions, the use of substandard materials, details and construction practices may result in inadequate performance as highlighted in the 2010 earthquakes in Haiti and Chile. In the aftermath of an earthquake, households are often reluctant to reoccupy their dwellings due to concerns about safety of structures. If feasible, preventive (pre-hazard) strengthening or structural repair …

Applications Of Remote Sensing To The Study Of Estuarine Physics: Suspended Sediment Dynamics In The Columbia River Estuary, Austin Scott Hudson

Dissertations and Theses

Estuarine circulation and its associated transport processes drive the environmental integrity of many near-shore habitats (the coastal ocean, rivers, estuaries and emergent wetlands). A thorough understanding and consideration of this circulation is, therefore, vital in the proper management of these habitats. The aim of this study is to bring together theory and new satellite observations in the Columbia River Estuary to increase our understanding of estuarine circulation and transport. Surface reflectance measurements gathered by the Moderate Imaging Spectroradiometer (MODIS) are first compared to in situ observations to develop an empirical model for remotely derived surface turbidity. Results indicate that MODIS …

Treatment Of Synthetic Oil Sands Tailing Water With Activated Carbon, Alfredo Martinez Iglesias

Electronic Thesis and Dissertation Repository

The extraction of bitumen from the Canadian tar sands has thus far generated approximately 840 billion liters of oil sands process affected water (OSPW) that is currently being stored in containment ponds. OSPW is known to be acutely toxic to various organisms, due to the presence of naphthenic acids (NAs). The scale and sheer volume of OSPW being stored in tailing ponds have generated serious public concerns. Many emerging technologies have been investigated as treatment options for OSPW reclamation. This work studied the feasibility of using granular activated carbon (GAC) to adsorb several naphthenic acids in a model solution of …

Scale-Up Methodology For Bench-Scale Slurry Photocatalytic Reactors Using Combined Irradiation And Kinetic Modelling, Patricio J. Valades Pelayo

Electronic Thesis and Dissertation Repository

The present study focuses on developing a predictive methodology to scale-up a slurry annular photoreactor using a TiO₂ Degussa P25 from the bench-scale to a pilot-plant scale. The bench-scale photoreactor is a Photo-CREC-Water II, a 2.65 L internally-irradiated slurry annular photocatalytic reactor. The pilot-plant scale photoreactor is a Photo-CREC Water Solar Simulator, a 9.8 L pilot-plant photoreactor, externally irradiated by eight lamps.

The adopted methodology allows the independent validation of radiative and kinetic models avoiding cross-correlation issues. The proposed approach involves two Monte Carlo methods, to model the Radiative Transfer Equation (RTE) inside each photoreactor. With this end, a …

Enhanced Dechlorination Of 1,2-Dichloroethane By Coupled Nano Iron-Dithionite Treatment, Ariel Nunez Garcia

Electronic Thesis and Dissertation Repository

1,2-dichloroethane (1,2-DCA) is a chlorinated solvent classified as a probable human carcinogen. Due to its extensive industrial applications, widespread contamination and recalcitrance towards abiotic dechlorination, 1,2-DCA remains a challenging compound for the remediation community and one of the great research interests. Batch experiments combining bimetallic or monometallic nZVI (stabilized or non-stabilized) with sodium dithionite were conducted for the degradation of 1,2-DCA. These experiments have yielded up to 92 % degradation of the initial 1,2-DCA concentration over the course of a year. Observed pseudo-first order rate constants (k_obs) range from 3.8 x 10^-3 to 7.8 x 10^{-3 …}

Influence Of Water Chemistry Parameters On The Dissolution Rate Of The Lead (Ii) Carbonate Hydrocerussite, Caitlin Se Kushnir

Electronic Thesis and Dissertation Repository

This work has focused on the kinetic dissolution of the lead (II) carbonate hydrocerussite (Pb₃(CO₃)₂(OH)₂) under four pH conditions (7.5, 8, 9, 10), three dissolved inorganic concentrations (DIC; 10, 20, 50 mg C/L), and three initial hydrocerussite concentrations (10, 20, 50 mg/L) in batch experiments. Experiments were performed in at least duplicate to determine total dissolved lead dissolution curves at short time scales (hr.). All equilibrium dissolved lead concentrations were achieved in 40 minutes or less, and matched trends from previous studies; pH 7.5 and pH 10 corresponding to the highest and …

Miniature Cone Penetration Test On Loose Sand, Sepideh Damavandinejad Monfared

Electronic Thesis and Dissertation Repository

Considering the difficulties associated with preparing loose sand samples in large calibration chambers and wide area of research on the behavior of loose sands, miniature calibration chamber experiments are used to perform cone penetration tests on soils in different states. A miniature cone calibration chamber has been designed and developed in this study. Nineteen tests have been performed on Ottawa sand and the results are compared to the available data in the literature. The accuracy of the results is validated by comparing the results with the suggested rate for the cone resistance in sands in literature. More specifically, results are …

Behavior Of Larger-Diameter Strands In The Disturbed Region Of Prestressed Concrete Girders, John Verlin Cabage Jr.

Doctoral Dissertations

Traditionally, the Tennessee Department of Transportation has been using American Association of State Highway and Transportation Officials – Prestressed/Precast Concrete Institute Bulb Tee (AASHTO-PCI BT) sections for its prestressed concrete bridges. These sections have limited bottom flange widths where the prestressing strands are located. To increase span capacities of these sections, other States have adopted new sections with a wider flange width. Producers in Tennessee have raised concerns about the cost of the new steel forms to accommodate these new sections. As an alternative, this research examines the use of larger diameter strand in conjunction with high-strength concrete and standard …

Blending Issues Of Hot And Warm Mix Asphalt Containing Recycled Asphalt Pavement And Recycled Asphalt Shingle, Sheng Zhao

Doctoral Dissertations

The current tendency in paving industry is to increase the use of recycled asphalt pavement (RAP) and recycled asphalt shingle (RAS). However, one of the reasons that limit the high recycled amount is the unknown blending between virgin and RAP/RAS binders. A series of studies were conducted in this dissertation to address blending issues in warm mix asphalt (WMA) and hot mix asphalt (HMA) containing RAP and RAS, in terms of evaluation of recycled binder mobilization, binder homogeneity and WMA effects on blending.

Partial blending was observed in RAS mixtures and the most efficient blending occurred at approximately 5% RAS …

Determination Of Area Of Fire Origin Through Examination Of Structural Failure And Deformation, Andrew Thomas Tinsley

Doctoral Dissertations

The effects of fire on steel have long been noted and studied. However, a scientific connection between the area of origin for a fire and the amount of steel deformation observed at the scene has never been established. The development and implementation of this type of analysis has the potential to decrease investigation times significantly as the types of structures to which this method would be applicable are typically large, expansive structures. In order to investigate the relationship between structural steel deformations and a fire’s origin, a series of six tests were performed in a smaller size portal frame steel …

Mechanical Properties Of Glass Fiber Reinforced Polymer Bars After Exposure To Elevated Temperatures, Mohammed Abdulqader Jalil Alsalihi

Theses and Dissertations

ABSTRACT

MECHANICAL PROPERTIES OF GLASS FIBER REINFORCED POLYMER BARS AFTER EXPOSURE TO ELEVATED TEMPERATURES

by

Mohammed A. J. Alsalihi

The University of Wisconsin-Milwaukee, 2014

Under the Supervision of Professor Habib Tabatabai

In the past few decades, the use of composite materials has become more widespread in different fields and industries. Part of this increase comes as an answer to the corrosion issues that ordinary steel faces. Fiber Reinforced Polymers (FRP)s offer a number of advantages that make them an adequate solution to challenges in the rapidly developing construction industry. However, the behaviors of these materials at elevated temperatures and their …

Reliability-Based Design And Acceptance Protocol For Driven Piles, Joseph Jabo

Graduate Theses and Dissertations

The current use of the Arkansas Standard Specifications for Highway Construction Manuals (2003, 2014) for driven pile foundations faces various limitations which result in designs of questionable reliability. These specifications are based on the Allowable Stress Design method (ASD), cover a wide range of uncertainties, do not take into account pile and soil types, and were developed for general use. To overcome these challenges it is deemed necessary to develop a new design and acceptance protocol for driven piles. This new protocol incorporates locally calibrated RLFD resistance factors for accounting for local design and construction experiences and practices, as well …

Calibration Of Resistance Factors For Driven Piles Using Static And Dynamic Tests, Deshinka A. Bostwick

Graduate Theses and Dissertations

The field of geotechnical engineering has evolved from Allowable Stress Design (ASD) to Load Factor and Resistance Design (LRFD) which has led to a need to quantify the measures of uncertainty and the level of reliability associated with a project. The measures of uncertainty are quantified by load and resistance factors, while the level of reliability is driven by the amount of risk an owner is willing to take and is quantified by the reliability index. The load factors are defined through structural design codes, but the resistance factors have uncertainties that can be mitigated through reliability based design. The …

Microbial Community Shifts Caused By Changes In The Primary Oxidant At A Drinking Water Treatment Plant, Connie Marie Moloney

Graduate Theses and Dissertations

Microbial communities resistant to common oxidants can cause concerns for water treatment plants (WTPs). If a bacterium is not fully oxidized during disinfection, these species can impede upon filtration processes or seed biofilms in the distribution system. In an effort to minimize disinfection by-products (DBP's) that result from the reaction of chlorine (Cl2) with natural organic matter, water treatment plants have the option to change their primary oxidant to chlorine dioxide (ClO2). The following study examines the change in microbial communities during the sedimentation process under differing oxidation regimes, specifically chlorine (Cl2) and ClO2 at the local water treatment plant …

Cal Poly India Project, Derek Babine, Austen Hibler, Alex Hernandez

Mechanical Engineering

This report documents the research, ideation, and development of a solution, implemented by the Cal Poly India Sanitation Team per the request of Mr. Harish Bhutani, to solve the problem of hazardous human waste management in poor villages in India. The sponsor envisioned a universal design that would give each household in those villages access to a private toilet system because the current solution is open defecation in water sources and farming fields. The initial constraints required the project be low cost, not use of electricity or water, have the ability to cater to an 8-10 person household, and be …

Effect Of Caliche On The Behavior Of Drilled Shafts, Rouzbeh Afsharhasani

UNLV Theses, Dissertations, Professional Papers, and Capstones

The current design methodology for a drilled shaft foundation in cohesionless soil is primarily based on ultimate skin friction values of drilled shafts. In order to obtain these values for each soil type, load tests such as Osterberg test are designed and performed. The Osterberg test layout is designed to estimate the capacity of drilled shaft by applying an upward load during the test and then calculating the downward capacity assuming the upward and downward capacity are the same. This method is appropriate for soils not containing caliche layers because caliche layers bond to the shaft and prevent skin friction …

Evaluation Of Phb Mid-Street Crossing System In Las Vegas, Nevada - Pedestrian Perspectives, Anna Eapen

UNLV Theses, Dissertations, Professional Papers, and Capstones

As the U.S. population ages and as more people choose to walk, it is critical to improve pedestrian safety. One of the best ways to encourage both pedestrians and vehicle drivers to behave safer is to make use of the most effective engineering traffic control systems. One such new technology is the Pedestrian Hybrid Beacon System (PHB), formerly known as the High-intensity Activated crosswalk (HAWK), a pedestrian-activated traffic-warning device. It features immediate activation of traffic warning lights from a dark state, a pedestrian countdown timer, and shorter pedestrian crossing times and traffic stoppage times compared to a traditional midblock traffic …

Identification Of Long Term Changes And Evaluation Of The Relationships Among Streamflow Variability And Oceanic-Atmospheric Indices, Soumya Sagarika

UNLV Theses, Dissertations, Professional Papers, and Capstones

To examine the effects of climate variability on streamflow, this thesis presents a comprehensive analysis of the streamflow variability of the continental United States and its association with oceanic-atmospheric indices. First, the presence of trends with consideration of short term and long term persistence followed by shifts over the past years in the continental U.S. streamflow were analyzed by using the non-parametric tests: Mann Kendall and Pettitt. Second, the spatio-temporal relationships between seasonal streamflow variability of continental U.S. and sea surface temperatures (SST) and 500 mbar geopotential height (Z500) of the Pacific and Atlantic were established using the singular valued …

Toward Understanding The Physiological Determinants Of Microbial Competitiveness In Methanogenic Processes, Si Chen

Doctoral Dissertations

Methanogenesis is of great significance in both natural and engineered processes. Anaerobic digestion technology represents the engineering-scale implementation of methanogenesis in waste treatment processes. Despite the broad application of anaerobic digestion as a common waste treatment option, much remains to be learned on the anaerobic food web underlying methanogenesis for more effective process modeling and control.

Following an initial screening of various substrates, six continuous lab-scale anaerobic digesters were developed with animal waste as the substrate. The linkage between microbial community composition and process performance was studied by initiating process imbalance with organic overloading. As a result, accumulation of short …

Recycling Wastewater For Hydraulic Fracturing By Use Of Nanofiltration Membranes, Haley D. Cleous

Chemical Engineering Undergraduate Honors Theses

Hydraulic fracturing creates large volumes of produced water, contaminated with organics, suspended solids, and dissolved minerals. This water must either be disposed of in injection wells or treated for reuse. One option is to use a combination of ultrafiltration and nanofiltration to treat this water and reuse it in future hydraulic fracturing wells. The object of this study was to test and characterize commercial nanofiltration membranes. The work done for this project will lead to future work in modifying membranes to improve the rejection of desired components.

Evaluating The Effectiveness And Hydrological Performance Of Green Infrastructure Stormwater Control Measures., Hamidreza Kazemi

Electronic Theses and Dissertations

The Louisville and Jefferson County Metropolitan Sewer District (MSD) has developed a Long-Term Control Plan (LTCP) to address the combined sewer overflow (CSO) issue through a combination of gray and green infrastructure (GI) stormwater management practices in the city of Louisville. In support of this effort, the MSD installed a series of GI stormwater control measures (SCMs) to abate the CSO volumes in an urban sewershed basin. This research is focused on monitoring and evaluating the individual hydrological performance, which included infiltration and exfiltration processes, of two permeable pavement systems over a two year study period. It also assess the …