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Modeling Biodegradation Of Chlorinated Groundwater Contaminants Under Iron-Reducing Conditions Of A Constructed Wetland: A System Dynamics Approach, Max E. Johnson

Theses and Dissertations

The purpose of this study is to determine and explore the fundamental processes associated with biodegradation of chlorinated ethenes in iron-reducing conditions of a constructed wetland and to evaluate the impacts of changing conditions (both natural and engineer-controlled) on the system. The modeler uses a system dynamics approach to construct a model that represents behavior in the iron-reducing environment. The model incorporates hematite, a form of oxidized iron (Fe³⁺), as the electron acceptor in microbial biodegradation in the system. Vinyl chloride, cis-dichloroethene, and trans-dichloroethene are known to anaerobically degrade to carbon dioxide in the presence of oxidized iron. …

Determining The Value Of Groundwater Contamination Source Removal: A Methodology, Benjamin C. Recker

Theses and Dissertations

Subsurface contamination by industrial chemicals is one of the most prevalent and costly environmental problems facing the United States government. This contamination problem must be managed to protect human health and the environment. Two basic strategies are used to deal with subsurface contamination: source removal and contaminant containment. While much cost and performance data are available for individual technologies associated with each of these strategies, there have been very few studies that have examined the benefits of implementing source removal technologies in order to reduce contaminant containment (and hopefully total) costs. This study examines the tradeoff between extent of source …

Modeling Chlorinated Ethene Removal In The Methanogenic Zone Of Constructed Wetlands: A System Dynamics Approach, Randall L. Roberts

Theses and Dissertations

The purpose of this study is to gain understanding of the dynamics of the processes that degrade Perchloroethene (PCE) to ethene, within the confines of the methanogenic zone of a constructed wetland. A system dynamics modeling approach is used. This model is focused on determining conditions that will enhance contaminant degradation. The chemical and biological processes within the methanogenic zone of a wetland system are extremely complex and dynamic processes. The model is broken up into three simultaneous processes: dechlorination, methanogenesis, and fermentation. The system behavior of the methanogenic zone can be adequately described by the classical formulations of representative …

A Model For Palladium Catalyzed Destruction Of Chlorinated Ethenes In Contaminated Groundwater, Christopher M. Stoppel

Theses and Dissertations

Groundwater contamination by chlorinated ethenes is a widespread environmental problem. Conventional remediation technologies have shortcomings that have prompted further research into the development of novel treatment technologies. A palladium/ alumina catalyst in the presence of dissolved molecular hydrogen (referred to hereafter as a PD/H₂ system) has been demonstrated to rapidly destroy chlorinated ethene contaminated groundwater. First-order kinetics have been used to model chlorinated ethene destruction in a PD/H₂ reactor. However, catalyst deactivation and regeneration are important processes that also need to be modeled in order to better understand their effect on treatment efficiency. This study presents a model …

Quantitative Validation Of A Model Of Chlorinated Ethene Natural Attenuation, Harold C. Young

Theses and Dissertations

Chlorinated ethenes are among the most prevalent groundwater contaminants at hazardous waste sites nationwide. In an attempt to manage the risks posed by these contaminants, while controlling costs, monitored natural attenuation (MNA) is being considered as a remediation strategy at many sites. MNA relies on naturally occurring physical, chemical, and biological processes in the subsurface to reduce the risk posed by the contamination. The implementation of MNA, however, requires a detailed understanding of these processes, and how they impact contamination at a particular site. One way to gain this understanding is through contaminant fate and transport modeling. In this study, …

Tidal Asymmetry In An Estuarine Pycnocline 2. Transport, David A. Jay, Cynthia N. Cudaback

Civil and Environmental Engineering Faculty Publications and Presentations

Flood currents in shallow estuaries are driven by an along-channel barotropic and baroclinic pressure gradient that increases monotonically toward the bottom, while friction retards near-bottom currents. Therefore, in many estuaries there is a middepth maximum in flood currents. We explore this phenomenon using a simple three-layer model in which each layer has vertically uniform currents and constant density. In this model the middle layer is of intermediate density and grows by shear-induced entrainment from the other two layers. This very simple model produces a middepth maximum in flood currents and simulates observed currents in the Columbia River entrance channel within …

Assessing The Economic Impact Of Aircraft Noise On Communities, Ithan B. Zimmer

Dissertations

The impact of aircraft noise on communities is complex and multi-dimensional. This matter cannot be resolved without careful analysis of a complex array of related problems and issues including the environment, the economy, and quality-of-life concerns of people living in proximity to airports or aircraft routes. The effects of community noise are widespread and varied. Impacts can include sleep and speech interference, activity interference, general annoyance, and property value decrease. In order to improve public policy and provide a foundation for additional research, it is imperative to establish the extent of a problem. Dollars are often the least common denominator …

Optimization Of Nitrogen Removal In Sequencing Batch Reactor, Suppakit Poonyachat

Theses

Operating parameters for sequencing batch reactor have the influenceon each substrate concentration. Concentration profile changes as operationparameters are changed. The study was conducted to model the variationin effluent concentration from sequencing batch reactor. MLVSS and cycletime are the parameters that were varied. Concentration in Fill, React,and Settle Period were calculated by using kinetic equations.

The results can show that these parameters have effects on the concentrationprofile. The increase of MLVSS can lower the concentration of BOD andammonium concentration in React period. Increasing MLVSS can show thatmore substrate utilization and nitrification process occur more rapidly.Concentration of nitrate at the end of …

Development Of A Low-Cost, Self-Calibrating Stream Gaging Station, Gilberto Urroz, Robert C. Leines, Garryn L. Perret, Jared M. Holland, Brian E. Hunsaker

Reports

Executive Summary: The present report presents a review of the state-of-the-art technologies for the development of a low-cost, self-calibrating stream gaging station. The research was conducted by the Utah Water Research Laboratory with funding provided by the Utah Division of Water Resources through Project RP 110080, March 1998. The report presents a review of the current practices in stream gaging and how technologies such as remote data telemetry through the use of satellite, cellular phone communications, and radio telemetry can be used for the real-time transmission of data. The study also includes the use of Global Positioning System (GPS) for …

Water Distribution Modeling, Thomas M. Walski, Donald V. Chase, Dragan A. Savic

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

To effectively use water distribution models, the engineer must be able to link knowledge of basic hydraulic theory and the mechanics of the program with that of the operation of real-world systems. Water Distribution Modeling does just that.

Written by industry experts, it provides a practical resource for engineers and modelers that goes well beyond being a how-to guide for typing data into a computer program. It contains straightforward answers to common questions related both to modeling and to distribution systems in general.

This textbook walks the practicing engineer or student through the modeling process from start to finish — …

Polyurethane Foam Based Packing Media For Biofilters Removing Volatile Organic Compounds From Contaminated Air, Felipe A. Martinez

LSU Master's Theses

In recent years, biofiltration technology has gained acceptance worldwide as an economical and reliable air pollution control technology for treating gases contaminated by low concentrations of biodegradable volatile organic compounds (VOCs). Important applications include control of odors generated by wastewater treatment plants and control of VOC emissions from industrial sources. Although there have been many successful applications, several operational problems have been reported in the literature. These include difficulty in control over bed moisture content, high head loss caused by excessive biomass production, and inability to maintain removal efficiency during transient periods of high concentration loading. Use of a superior …

Concrete Roughness Characterization Using Laser Profilometry For Fiber-Reinforced Polymer Sheet Application, Norbert H. Maerz, Poornima Chepur, John J. Myers, Justin Linz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The failure of a reinforced concrete member strengthened with fiberreinforced polymer (FRP) laminates may be caused by crushing of concrete, rupture of FRP laminates, or delamination of the FRP sheet. Therefore, the effectiveness and failure mode of FRP sheets applied to beams and columns is related to the degree of adhesion of the epoxy to the concrete surface. When a peeling or delamination failure can be avoided, a more effective engagement of the FRP sheet occurs, which results in more efficient use of the material. One of the principal factors affecting the bond behavior between the concrete and epoxy is …

Simulation/Optimization Applications And Software For Optimal Ground-Water And Conjunctive Water Management, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Diverse water management simulation/optimization (S/O) experiences promoted the development of many S/O modeling approaches and models. Several of these are being incorporated within the Simulation/Optimization Modeling System (SOMOS). Non-modeler water scientists or engineers can apply one SOMOS module to optimize field-scale groundwater and conjunctive water management. Experienced groundwater modelers can apply other modules to optimally manage complex heterogeneous aquifer and stream-aquifer systems. SOMOS employs a variety of simulation models and approaches and optimization algorithms to optimize flow and contaminant management. SOMOS or its precursor modules have been well proven in real-world projects. Designed for use by consultants, students, academics, and …

Real-Time Determination Of Soil Type, Water Content, And Density Using Electromagnetics, Vincent P. Drnevich, Chih-Ping Lin, Quanghee Yi, Janet Elaine Lovell

JTRP Technical Reports

The primary objective of this study was to explore the potential use of electromagnetic characteristics of soils using the Time Domain Reflectometry (TDR) technique to identify physical properties of soils. Three fundamental studies in this exploration are the frequencydependent electromagnetic properties of soils, the wave propagation in a TDR system, and the inverse analyses of TDR waveforms. The three-phase model for soils was extended to a four-phase model so as to account for the interface effect and hence the soil fineness. The physical parameters of the four-phase model are related to the frequency-dependent dielectric permitivity of the soil through a …

Permeability Performance Of High-Performance Concrete Subjected To Various Curing Regimes, John J. Myers

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Concrete technology has continued to advance throughout the years to meet the demands of designers and innovative structural systems. Traditionally, the most common means to specify durable concrete has been via specifying a maximum water-to-cementitious material ratio or a minimum cement content. With the advent of high-performance concrete (HPC), which often has higher contents of cementitious materials and a variety of admixtures, questions about permeability performance and alternative methods to specify durable concrete have arisen. The study conducted herein comments on the applicability of prescriptive specifications for HPC and investigates the influence of curing regimes and concrete temperature development during …

Waste Management In Palm-Oleo Sdn. Bhd, Ramesh Ramasamy

Student Works (2000-2009)

Oleochemical industry in Malaysia has been diversifying significantly due to the availability of raw materials (palm oil) and the high demand for downstream products such as fatty acids, fatty alcohols and glycerine. The growth of oleochemical industries is further enhanced by fluctuations io petroleum price and regular animal diseases, which made tallow-based fats unreliable. Environmental awareness is growing rapidly in Malaysia. There is growing realization of the need to balance industrial and economic development with environmental preservation and protection, as well as, with efficient use of energy sources in order to achieve sustainable development. Extensive waste management studies were focused …

Comparative Performance Of Wastewater Treatment Plants In Three Rubber Glove Manufacturing Plants, Lee Kuan Loh

Student Works (2000-2009)

During the manufacturing of rubber gloves, water is used as wash water at different stages to clean the rubber gloves, thus generating quite a substantial amount of effluent. There are four main sources of effluent. i.e. a) from the glove formers cleaning tank, which collects the acidified water used to clean these formers, b) latex dipping tank, where it collects wash water used to cool the tank during dipping process and the sludge form the tank itself, c) leaching tank, where it collects wash water used to leach out the pollutants from the gloves and lastly d) latex compounding, containing …

Studies On The Pollution Parameters Of Leachate From Ampang Landfill, Syed Fatimah Kamal Batcha

Student Works (2000-2009)

ln the first part of the study, the characteristics of the leachate from Ampang landfill, collected before and after the landfill closure was analysed. In general, the characteristics of the Ampang landfill leachate was found to be typical of other landfill leachates in the Klang Valley. The analysis reveals that the Ampang landfill leachate during its active life had high contents of sodium, potassium, chloride and ferum, with concentrations of 687 ppm, 785 ppm, 2500 ppm and 45 ppm respectively. Generally and as expected, the leachate collected before the landfiII closure was found to be more concentrated and contains more …

Assessing Methodologies For Identification Of Significant Impacts In The Iso 14001 Ems (Environmental Management Systems), Ann Wye-Wye Wang

Student Works (2000-2009)

ISO 14001 is a voluntary environmental management system specification standard in the ISO 14000 series. It contains those elements that must be satisfied by an organisation seeking registration or certification to the standard. Identification of significant environmental impacts is one of the requirements as stated in clause 4.3.1 of MS ISO 14001 EMS - specification with guidance for use, and is an important step in the implementation of ISO 14001 standard. A study on the methodologies for identification of significant environmental impacts in the ISO 14001 EMS (Environmental Management Systems) was carried out. Three methods that have been developed are …

Development Of A Physico-Chemical Wastewater Treatment Strategy For A Chemical Plant, T. Alagarajah K. Thavarajah

Student Works (2000-2009)

A study was carried out to determine the physico-chemical treatment of the wastewater collected from a soap and detergent factory in Selangor, Malaysia. The study was initiated by determining the characteristics of the wastewater. Treatability studies involving coagulation and flocculation were determined by the jar test method. The parameters of interest were coagulant dosage, pH, mixing intensity, mixing time and settling time. The coagulants were restricted to alum and ferric sulfate and coagulant aids utilized were polyvinyl alcohol, sodium alginate and polycthylcninimine. An extended evaluation to determine the effect of double chemical treatment was also carried out with the most …

Linearly Unbiased Estimation Combined With Jc Method For The Carbonation Contamination Of Some Concrete Bridges In Taipei, Ming-Te Liang, Guo-Fan Zhao, Yen-Sheng Liao, Chih-Hsin Liang

Journal of Marine Science and Technology–Taiwan

The main purpose of this investigation was to study the durability evaluations of existing concrete bridges due to carbonation contamination. The linearly unbiased estimation method associated with the JC method developed by the Joint Committee on Structural Safety was adopted to predict the mean value and standard deviation of the normal distribution for the carbonation depths and cover thickness of concrete bridges. The reliability index (β) and failure probability (Pf) of concrete bridges were also evaluated. Since the linearly unbiased estimation method is very suitable for analyzing a small number of specimens obtained from practical engineering problems, the unknown parameters …

Simplified Window Glass Design Procedure, H. Scott Norville, Joseph E. Minor

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents a simplified window glass design procedure (SWGDP) as an alternative to the comprehensive window glass design procedure described in ASTM E 1300, `Standard practice for determining the load resistance of glass in buildings.' Although ASTM E 1300 provides a technically robust treatment of the strength of window glass and window glass constructions, architects and engineers will find ASTM E 1300 difficult to use. The SWGDP presented herein uses the same failure prediction methodology to characterize the annealed window glass strength that underlies ASTM E 1300. By reducing the number of basic glass strength charts to one, the …

Alternative Principal Components Regression Procedures For Dendrohydrologic Reconstructions, Hugo G. Hidalgo, Thomas C. Piechota, John A. Dracup

Civil and Environmental Engineering and Construction Faculty Research

Streamflow reconstruction using tree ring information (dendrohydrology) has traditionally used principal components analysis (PCA) and stepwise regression to form a transfer function. However, PCA has several procedural choices that may result in very different reconstructions. This study assesses the different procedures in PCA-based regression and suggests alternative procedures for selection of variables and principal components. Cross-validation statistics are presented as an alternative for independently testing and identifying the optimal model. The objective is to use these statistics as a measure of the model's performance to find a conceptually acceptable model with a low prediction error and the fewest number of …

Estimation Of Restraint Forces For Z-Purlin Roofs Under Gravity Loads, M. C. Neubert, Thomas M. Murray

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The current specification provisions for the prediction of lateral restraint forces in Z-purlin supported roof systems under gravity loads are in Section D3.1 of the 1996 AlSI Specification for the Design of Cold-Formed Steel Structural Members (1996). The provisions need refinement, because they are empirical, have an incorrect treatment of roof slope and system effects, and ignore the effect of panel stiffness on restraint forces. Therefore, a new restraint force design procedure, having a stronger reliance on engineering principles, is proposed. Elastic stiffness models, with varying roof slope, panel stiffness, and cross-sectional properties, were used to develop the procedure. A …

A Theoretical And Experimental Analysis Of Cold-Formed Steel Shapes Subjected To Bending - Channel And Simple Lipped Channel, Roberto Martins Goncalves, Maximiliano Malite, Carlos Eduardo Javaroni

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Cold-formed steel shapes have been widely employed in steel construction, where they frequently offer a lower cost solution than do traditional laminated shapes. A classic application of cold-formed steel shapes is purlins in the roof panel of industrial buildings, connected to the roof panel by means of screws. The combined effect of these two elements has been the subject of investigations in some countries. Design criteria were included in the AISI Code in 1991 and 1996. This paper presents and discusses the results obtained from bending tests carried out on shapes commonly used in Brazil, i.e., the channel and the …

Finite Element Analysis Of Cold-Formed Channel Columns, Ben Young, Jintang Yan

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The paper presents a numerical investigation into the behaviour and strengths of cold-formed plain and lipped channel columns using finite element analysis. A non-linear finite element model is developed and verified against the fixed-ended channel column tests conducted by Young and Rasmussen (1998a, 1998b and 1998c). Geometric and material non-linearities were included in the finite element model. It is demonstrated that the finite element model closely predicted the ultimate loads and the behaviour of the tested cold-formed channel columns. Hence, the model was used for an extensive parametric study of cross-section geometries. Furthermore, the results of the numerical investigation are …

Web Crippling Data And Calibrations Of Cold Formed Steel Members, R. M. Schuster, B. Beshara

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Computing Optimal Pumping Strategies For Groundwater Contaminant Plume Remediation, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

Simulation/Optimization (S/0) models can greatly simplify the process of designing remediation systems for contaminated groundwater. We describe some technical aspects of using S/0 models and possible S/0 model formulations for groundwater remediation design. We: discuss some S/0 model optimization algorithms; illustrate simple optimization problem solution; describe two real-world S/0 model applications; and demonstrate S/0 model application under uncertainty.

Simulation Of Temperature And Stress Fields During Rcc Dam Construction, Ronaldo Luna, Yongfu Wu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The worldwide experience in the construction of roller-compacted concrete (RCC) dams together with the use of numerical solutions, allows the simulation of different scenarios in a computer. It is well documented that thermal control is one of the most important problems for RCC dam construction. The dam temperature changes due to the heat produced by the internal hydration of concrete and the environmental boundary conditions influencing the elastic modulus and creep properties of concrete. The construction process was simulated to study how the temperature and stress change during dam construction. The numerical methodology considers the effect of temperature on the …

Wavelet-Based Approach For Structural Damage Detection, Z. Hou, Mohammad N. Noori, R. St. Amand

Office of the Dean (CENG) Scholarship

A wavelet-based approach is proposed for structural damage detection and health monitoring. Characteristics of representative vibration signals under the wavelet transformation are examined. The methodology is then applied to simulation data generated from a simple structural model subjected to a harmonic excitation. The model consists of multiple breakable springs, some of which may suffer irreversible damage when the response exceeds a threshold value or the number of cycles of motion is accumulated beyond their fatigue life. In cases of either abrupt or accumulative damages, occurrence of damage and the moment when it occurs can be clearly determined in the details …