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Anaerobic Membrane Bioreactors To Treat Municipal Wastewater At Ambient Temperatures, Matthew D. Seib Oct 2015

Anaerobic Membrane Bioreactors To Treat Municipal Wastewater At Ambient Temperatures, Matthew D. Seib

Dissertations (1934 -)

Anaerobic biotechnology is viewed as a sustainable alternative to aerobic biotechnology for municipal wastewater recovery. However, anaerobic processes have not been successful in cold climates. Past examples have not been able to meet low organic effluent concentrations, or have failed due to biomass washout resulting from low temperature operation and short hydraulic residence time. Recently, the anaerobic membrane bioreactor (AnMBR) has been shown to achieve low effluent organic concentrations and maintain stable anaerobic biomass. However, shortcomings have included high energy demands for membrane operation and poor understanding of microbial community structures within AnMBRs. This dissertation describes efforts to improve AnMBRs …


The Contribution Of Syntrophic Fatty-Acid Degrading Microbial Communities To Anaerobic Digester Function And Stability, Prince Peter Mathai Oct 2015

The Contribution Of Syntrophic Fatty-Acid Degrading Microbial Communities To Anaerobic Digester Function And Stability, Prince Peter Mathai

Dissertations (1934 -)

Anaerobic digestion (AD), the conversion of complex organic matter to methane, occurs through a series of reactions mediated by different guilds of microorganisms. AD process imbalances, such as organic overload or high organic loading rates (OLR), can result in the accumulation of volatile fatty acids (VFA) e.g., propionate, which must be degraded to maintain stable reactor function. VFAs are metabolized by syntrophic fatty-acid degrading bacteria (SFAB) in association with methanogenic archaea (collectively, syntrophic microbial communities, SMC). Despite their indispensable role in AD, little is known about the ecology of SFAB, especially under stressed conditions. To facilitate ecological studies, four quantitative …


A Semantics-Based Approach To Construction Cost Estimating, Mehrdad Niknam Oct 2015

A Semantics-Based Approach To Construction Cost Estimating, Mehrdad Niknam

Dissertations (1934 -)

A construction project requires collaboration of different organizations such as owner, designer, contractor, and resource suppliers. These organizations need to exchange information to improve their teamwork. Understanding the information created in other organizations requires specialized human resources. Construction cost estimating is one of the processes that requires information collected from several sources including a building information model (BIM) created by designers, estimating assembly and work item information maintained by contractors, and construction resource cost information provided by resource suppliers. Currently, it is not easy for computers to integrate the information for construction cost estimating over the Internet. This study discusses …


Municipal Wastewater Anaerobic Treatment With Enhanced Clarification, Kevin Berg Jul 2015

Municipal Wastewater Anaerobic Treatment With Enhanced Clarification, Kevin Berg

Master's Theses (2009 -)

As energy costs rise, water reclamation facilities (WRFs) desire lower cost, easily operated systems to remove BOD5 and suspended solids. WRFs typically utilize an aerobic process called activated sludge to remove biochemical oxygen demand (BOD). BOD, specifically 5 day BOD (BOD5), is used as an indicator of the organic strength of a solution. Anaerobic treatment provides an alternative to activated sludge by removing BOD5, generating biogas containing methane for energy and producing less biomass that requires disposal. Anaerobic treatment functions as an exceptional alternative to activated sludge when packaged as a system with a small footprint that operates at ambient …


Implications Of Heterogeneity In The Shock Wave Propagation Of Dynamically Shocked Materials, Jeffrey W. Lajeunesse Apr 2015

Implications Of Heterogeneity In The Shock Wave Propagation Of Dynamically Shocked Materials, Jeffrey W. Lajeunesse

Master's Theses (2009 -)

The field of shock physics as a whole has only recently begun to pay particular attention to modeling heterogeneous materials under shock loading. These materials are important because of their practicality in terms of creating stronger, more shock resistant materials. To understand why they absorb shock impact energy better than homogeneous materials means that the small-scale processes that occur during the shock loading of these heterogeneous materials needs to be understood. Recent computational experiments, called mesoscale simulations, have shown that explicitly incorporating small-scale heterogeneous features into hydrocode simulations allows the bulk shock response of the heterogeneous material to be observed …


Pyrolysis For Estrogens Removal From Wastewater Solids, Thomas C. Hoffman Apr 2015

Pyrolysis For Estrogens Removal From Wastewater Solids, Thomas C. Hoffman

Master's Theses (2009 -)

Wastewater treatment processes are not designed to remove estrogenic micropollutants and therefore when wastewater biosolids are land applied estrogenic micropollutants are discharged to the environment. Release of estrogenic compounds has deleterious effects on the terrestrial environment. Public concern stemming from micropollutants may reduce the value of biosolids which are important to water resource reclamation facilities (WRRF) as by-products. The objective of this research was to evaluate pyrolysis, the partial decomposition of organic material in an oxygen-deprived system under high temperatures, as a sustainable solution to remove estrogenic compounds from biosolids while producing a useable soil conditioner called biochar. Batch pyrolysis …


Nutrient Recovery From Anaerobic Membrane Bioreactor Permeate Using Ion Exchange, Patrick Mullen Apr 2015

Nutrient Recovery From Anaerobic Membrane Bioreactor Permeate Using Ion Exchange, Patrick Mullen

Master's Theses (2009 -)

Phosphorus is a common element in wastewater streams and traditional treatment processes are often designed remove it to achieve low effluent limits. Such processes often do not often consider the potential value of the nutrient. Currently, production of phosphate fertilizers has dramatically risen causing concern for the depletion of phosphate rock reserves, bringing about exploration into alternative sources of phosphorus for agricultural use. Combining the needs of phosphorus removal from wastewaters and securing alternate sources of the nutrient provide an opportunity for recovery. This project evaluated a nutrient recovery process through ion exchange with beneficial recovery as precipitated struvite using …


Removal Of Trace Heavy Metals From Drinking Water By Electrocoagulation, Joe Heffron Apr 2015

Removal Of Trace Heavy Metals From Drinking Water By Electrocoagulation, Joe Heffron

Master's Theses (2009 -)

Geologic and anthropogenic heavy metals contaminate drinking water for hundreds of millions of people worldwide. Electrocoagulation -- the in situ generation of coagulant by electrolytic oxidation of metal electrodes -- is a century-old process gaining new traction for metal removal from water and wastewater. However, the low conductivity of drinking water and low target contaminant concentrations required for human consumption present challenges for electrocoagulation of drinking water. This study is unique in that it addresses seven different metal contaminants at the trace concentrations of concern to human consumption and investigates the wide range of possible source water matrices. The goal …