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Full-Text Articles in Environmental Engineering

Overcoming Technological Challenges For The Commercialization Of The Circulating Fluidized Bed Bioreactor For Municipal Wastewater Treatment, Michael J. Nelson Dec 2021

Overcoming Technological Challenges For The Commercialization Of The Circulating Fluidized Bed Bioreactor For Municipal Wastewater Treatment, Michael J. Nelson

Electronic Thesis and Dissertation Repository

The fluidized bed bioreactor as an attached growth wastewater treatment process has demonstrated advantages over suspended growth processes for municipal wastewater treatment applications. However, previous studies have also demonstrated potentially serious disadvantages in terms of energy consumption and maximum reactor size of high flow applications.

In this work, a cost analysis using the CapdetWorks, supplemented by calibrated model data taken from GPS-X was performed to determine the cost effectiveness of the circulating fluidized bed bioreactor (CFBBR). This study demonstrated that the CFBBR is most cost competitive at low flow below 5 MGD. A 10%-20% reduction in net present values on …


Bioremediation Of Refinery Desalter Effluent Using Debaryomyces Hansenii And Parachlorella Kessleri, Leila Azimian Oct 2019

Bioremediation Of Refinery Desalter Effluent Using Debaryomyces Hansenii And Parachlorella Kessleri, Leila Azimian

Electronic Thesis and Dissertation Repository

Crude oil desalting operations produce an effluent stream which is challenging to treat due to its salt, heavy metal and hydrocarbon content. Consequently, desalter effluent (DE) is usually diluted into other effluent streams and sent to conventional wastewater treatment plants which may lead to upsets the plant operation.

In this study, a novel microbial approach was applied which investigated DE treatment using halotolerant yeast Debaryomyces hansenii (LAF-3 10 U) or the environmentally robust micro-algae Parachlorella kessleri strain CPCC 266. The effect of these two different approaches on both synthetic and actual DE was investigated in both batch and/or continuous mode. …


Maintaining And Controlling An Extrinsic Biofilm For Pathogen Removal In Dental Unit Water Lines, Bilal B. Al-Bataina Apr 2018

Maintaining And Controlling An Extrinsic Biofilm For Pathogen Removal In Dental Unit Water Lines, Bilal B. Al-Bataina

Electronic Thesis and Dissertation Repository

The control of biofilm formation is a major concern for industrial, environmental, and public health. Undesirable biofilms can harbor different disease-causing pathogens and shorten the operational life of different equipment. On the other hand, beneficial biofilms are also used in various applications and managing its growth and activity can be desirable. Killing the biofilm does not usually incorporate the removal of the dead biofilm structure that is adhered to the surface. Therefore, the aim of this thesis is to control biofilm formation; to be able to remove, inhibit, and enhance biofilm formation. This thesis investigated the use of norspermidine, D-amino …


Biobutanol Production From Cellulosic And Sugar-Based Feedstock From The Corn Plant, Reyna Gomez-Flores Apr 2018

Biobutanol Production From Cellulosic And Sugar-Based Feedstock From The Corn Plant, Reyna Gomez-Flores

Electronic Thesis and Dissertation Repository

In this thesis, biobutanol production by biological fermentation was investigated from the corn plant, integrating two approaches. The first one was to utilize corn cobs, a cellulosic-based material. The second, using a new sugar-based material, sugarcorn juice. Utilizing suitable Clostridia strains for each substrate, these approaches converged into a biorefinery concept to produce renewable biofuels in Ontario, Canada. The corn cob pretreatment was carried out by a dilute acid method resulting in temperature as the variable with most significant effect towards glucose liberation. The enzymatic hydrolysis was performed utilizing a very low concentration of an enzymatic stock solution with approximately …


Disinfection By-Products Formation After Coagulation Of Algal Extracellular And Intracellular Organic Matters, Tianyiru Chen Feb 2017

Disinfection By-Products Formation After Coagulation Of Algal Extracellular And Intracellular Organic Matters, Tianyiru Chen

Electronic Thesis and Dissertation Repository

Algal organic matter (AOM) is found in high concentration during algal bloom season in drinking water systems, which is generally categorized into extracellular organic matter (EOM) and intracellular organic matter (IOM). These compounds are not well removed in traditional water treatment methods such as coagulation, and are the precursors of subsequent disinfection by-products (DBPs) during chlorination of water. In this study, EOM and IOM content of four different algae were quantified measuring dissolved organic carbon (DOC), UV absorbance at 254 nm and turbidity. Coagulation using alum (Al2(SO4)3•16H2O)was used to remove the algal …


Hydrothermal Liquefaction Of High-Water Content Biomass And Waste Materials For The Production Of Biogas And Bio-Crude Oil, Laleh Nazari Aug 2016

Hydrothermal Liquefaction Of High-Water Content Biomass And Waste Materials For The Production Of Biogas And Bio-Crude Oil, Laleh Nazari

Electronic Thesis and Dissertation Repository

Growing interest in renewable energies due to shrinking reserves of fossil fuels and climate change concerns have led to extensive research towards gaseous and liquid fuels production from renewable energy resources such as biomass and wastes. Energy generation from municipal and industrial wastes such as wastewater sludge is also environmental friendly way to deal with large volume of waste disposal with the additional advantage of eliminating part of the indirect greenhouse gas emissions from energy crops-derived biofuels.

In this thesis, a novel process for co-production of biogas and bio-crude oil from high-water-content wastewater sludge through hydrothermal liquefaction (HTL) treatments is …


Application Of 3d Printing Technology In Porous Anode Fabrication For Enhanced Power Output Of Microbial Fuel Cells, Bin Bian Sep 2015

Application Of 3d Printing Technology In Porous Anode Fabrication For Enhanced Power Output Of Microbial Fuel Cells, Bin Bian

Electronic Thesis and Dissertation Repository

Microbial fuel cells (MFCs) are widely researched for application in wastewater treatment. However, the current anodes used in MFCs often suffer from high fabrication cost and uncontrollable pore sizes. In this thesis, three-dimensional printing technique was utilized to fabricate anodes with different micro pore sizes for MFCs. Copper coating and carbonization were applied to the printed polymer anodes to increase the conductivity and specific surface area. Voltages of MFCs with various anodes were measured as well as other electrochemical tests such as linear sweep voltammetry and electrochemical impedance spectroscopy. 3D copper porous anode produced higher maximum voltages and power densities …


Evaluation Of Filtration Performance Of A Rotating Belt Filter For Different Primary Wastewater Influents., Tulip Chakraborty Aug 2015

Evaluation Of Filtration Performance Of A Rotating Belt Filter For Different Primary Wastewater Influents., Tulip Chakraborty

Electronic Thesis and Dissertation Repository

Human activities around the world are responsible for production of enormous amount of wastewater, which needs to be treated quickly and effectively to avoid environmental concerns and other health implications. As an alternative to primary settlers in treating municipal wastewater, Salsnes, a subsidiary company of Trojan Technologies offers rotating belt filters (RBF) to treat the wastewater. A bench scale filtration unit of the RBF was developed to investigate the effect of varying water qualities from several wastewater plants in London, Ontario on the performance of the filter. The unit can achieve up to 80% reduction in total suspended solids (TSS), …


Process Control For Biological Nutrient Removal Processes In Fluidized Beds Treating Low Carbon To Nitrogen Municipal Wastewater, Joseph Donohue Jul 2015

Process Control For Biological Nutrient Removal Processes In Fluidized Beds Treating Low Carbon To Nitrogen Municipal Wastewater, Joseph Donohue

Electronic Thesis and Dissertation Repository

Conventional wastewater treatment techniques - utilizing microorganisms to remove organics and nutrients (i.e. nitrogen and phosphorus) from a water stream and partially incorporate them into their cell structure - struggle to adapt with increased urbanization due to land and infrastructure requirements. The circulating fluidized-bed bioreactor (CFBBR) was developed as a way to provide biological treatment in an urbanized area by cultivating high-density bacteria on an inert media. The technology operates as a pre-anoxic nitrification/denitrification wastewater treatment process. The system is initially loaded with media, providing a platform for microbial growth. Internal recycle streams in the system provide the energy to …


Solid-Phase Extraction As Sample Preparation For Bioassay-Based Micropollutant Quantification, Chen Feng Aug 2014

Solid-Phase Extraction As Sample Preparation For Bioassay-Based Micropollutant Quantification, Chen Feng

Electronic Thesis and Dissertation Repository

Solid phase extraction (SPE) using chemically bonded silica particles or small particles of an organic polymer resin, is being studied extensively for extraction of polar or non-polar compounds from various water matrices. This study focused on the evaluation of the performance of three commercial cartridges belonging to three different groups: reversed-phase, mixed-mode anion exchanger and mixed-mode cation exchanger. In the first stage of research, the performance of three cartridges was compared by extracting four antibiotics with different physic-chemical properties from water samples. The results obtained from column sorption experiments were plotted into breakthrough curves and batch equilibrium experiments results were …


Enhancement Of Biohydrogen Production From Co-Fermentation Of Glucose, Starch, And Cellulose, Medhavi Gupta Aug 2014

Enhancement Of Biohydrogen Production From Co-Fermentation Of Glucose, Starch, And Cellulose, Medhavi Gupta

Electronic Thesis and Dissertation Repository

The aim of this study was to assess the synergistic effects of co-fermentation of glucose, starch, and cellulose using anaerobic digester sludge (ADS) on the biohydrogen (H2) production and the associated microbial communities. At initial pH of 5.5 and mesophilic temperature of 37 ºC, the H2 yields were greater by an average of 27 ± 4% in all the different co-substrate conditions compared to the mono-substrate conditions, which affirmed that co-fermentation of different substrates improved the hydrogen potential. The sensitivity of mesophilic ADS to a temperature shock was also investigated. Unacclimatized mesophilic ADS responded well to a …


Fate Of Estrogens In Anaerobic Digestion And Their Removal In Advanced Oxidation, Shubhajit Sarkar Aug 2013

Fate Of Estrogens In Anaerobic Digestion And Their Removal In Advanced Oxidation, Shubhajit Sarkar

Electronic Thesis and Dissertation Repository

Estrogenic compounds are most significant endocrine disrupting compounds (EDC), which are of primary concern due to their widespread presence in the aqueous environment and also due to their adverse impact both on aquatic life and potential risk to human health. Conventional wastewater treatment plants are not designed to remove EDC, with biosorption on biosolids as the predominant removal mechanism. Anaerobic digestion is one of the most preferred processes employed for sludge stabilization in wastewater treatment plants. Advanced oxidation processes (AOPs) are seen as promising technologies for removal of estrogens from the environment. In this research, a controlled degradation study of …


Experimental & Empirical Correlations For The Determination Of The Overall Volumetric Mass Transfer Coefficients Of Carbon Dioxide In Stirred Tank Bioreactors, Syeda Anam Kazim Aug 2012

Experimental & Empirical Correlations For The Determination Of The Overall Volumetric Mass Transfer Coefficients Of Carbon Dioxide In Stirred Tank Bioreactors, Syeda Anam Kazim

Electronic Thesis and Dissertation Repository

One of the most important parameters to cultivate microalgae is carbon dioxide absorption by microalgae. Therefore, it is necessary to determine the overall volumetric mass transfer coefficient (KLa) of carbon dioxide to quantify CO2 transfer from the gaseous to the liquid phase. Until now, finding KLa of CO2 for microalgae cultivation has been a challenge as there is not much information available about it in the literature and most of the time the CO2 transfer to microalgae is approximated. In this study, correlations to directly calculate KLa of CO2 in …


The Effect Of Particle Size On Hydrolysis And Modeling Of Anaerobic Digestion, Saad Aldin May 2010

The Effect Of Particle Size On Hydrolysis And Modeling Of Anaerobic Digestion, Saad Aldin

Electronic Thesis and Dissertation Repository

Batch experiments were performed to investigate the effect of particulate protein particle size on the hydrolysis of casein in anaerobic degradation. While particle size did not affect the ultimate protein degradation efficiency, the hydrolysis rate coefficient increased from 0.034 to 0.298 d-1 with the change in specific surface area from 0.01 to 0.192 m2/g. The maximum methane production rate was affected by the particle size change, although the ultimate amount of methane produced was approximately the same despite the change in specific surface area. A mathematical relationship between the hydrolysis rate coefficient and specific surface area was developed and a …