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You searched for +publisher:"University of Colorado" +contributor:("M. Robin Collins"). Showing records 1 – 2 of 2 total matches.

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University of Colorado

1. Zearley, Thomas Lee. Biodegradation and Attenuation of Trace Organic Contaminants in Biological Drinking Water Filters.

Degree: PhD, 2012, University of Colorado

The occurrence of trace organic contaminants in drinking water sources concerns utilities since the human health risk is often unknown for many of the contaminants and their occurrence in mixtures complicates the health risk uncertainty. Drinking water treatment facilities are looking for technologies that remove trace organic contaminants to lower this potential risk. Biological filtration (biofiltration) can be an effective treatment process to reduce trace organic contaminants at little extra cost to most surface water treatment plants. The objectives of this thesis were to evaluate and model the effects of biological filter (biofilter) design and operation on trace organic contaminant removal. The long-term removals of 34 trace organic contaminants were evaluated at a constant influent concentration. The contaminants included pesticides, pharmaceuticals, and personal care products, some of which are endocrine disrupting chemicals, and represented a wide range of uses, chemical structures, adsorbabilities, and biodegradabilities. Contaminant removal ranged from no measurable removal to near-complete removal with effluent concentrations below the detection limit. Contaminant removals followed one of four trends: steady state removal throughout, increasing removal to steady state (acclimation), deceasing removal, and no removal (recalcitrant). Acclimation occurred at different rates depending on the contaminant and the community structure of the biofilter. Contaminant removals followed pseudo-first-order kinetics in drinking water biofilters and were modeled using a biomass based pseudo-first-order rate constant model. When a biofilter was intermittently exposed to a trace organic contaminant, the biofilter retained its biodegradation capacity for non-exposure events less than five months. Granular activated carbon (GAC) biofilters provided more stable removals under variable influent conditions (attenuation) as compared to a non-adsorptive media. The performance of trace organic contaminant removal in biological GAC (BAC) was a function of the adsorption affinity and biodegradability of a contaminant and the acclimation state of the biofilter. The framework for a biofiltration treatment technique for the control of trace organic contaminants was developed from the models and behaviors observed. Advisors/Committee Members: R. Scott Summers, JoAnn Silverstein, Fernando L. Rosario-Ortiz, Kevin M. McCabe, M. Robin Collins.

Subjects/Keywords: acclimation; bac; biofiltration; micropollutants; Environmental Engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Zearley, T. L. (2012). Biodegradation and Attenuation of Trace Organic Contaminants in Biological Drinking Water Filters. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/242

Chicago Manual of Style (16th Edition):

Zearley, Thomas Lee. “Biodegradation and Attenuation of Trace Organic Contaminants in Biological Drinking Water Filters.” 2012. Doctoral Dissertation, University of Colorado. Accessed December 14, 2019. https://scholar.colorado.edu/cven_gradetds/242.

MLA Handbook (7th Edition):

Zearley, Thomas Lee. “Biodegradation and Attenuation of Trace Organic Contaminants in Biological Drinking Water Filters.” 2012. Web. 14 Dec 2019.

Vancouver:

Zearley TL. Biodegradation and Attenuation of Trace Organic Contaminants in Biological Drinking Water Filters. [Internet] [Doctoral dissertation]. University of Colorado; 2012. [cited 2019 Dec 14]. Available from: https://scholar.colorado.edu/cven_gradetds/242.

Council of Science Editors:

Zearley TL. Biodegradation and Attenuation of Trace Organic Contaminants in Biological Drinking Water Filters. [Doctoral Dissertation]. University of Colorado; 2012. Available from: https://scholar.colorado.edu/cven_gradetds/242


University of Colorado

2. Terry, Leigh Gilmore. Organic Matter Removal via Biological Drinking Water Filters: Removal Efficiency Based on Quantifiable System Factors.

Degree: PhD, 2017, University of Colorado

Biodegradable organic matter (BOM), found in all surface waters, is a challenge for drinking water utilities as it can lead to distribution system bio-regrowth, react to form disinfection by-products, or be a specific compound of concern. Drinking water utilities face the challenge of removing BOM to meet increasingly stringent regulations, often at higher costs and operational complexity. Biofiltration can be an efficient treatment technology to remove BOM from the influent water, but should be optimized to achieve maximum removal performance. The objectives of this dissertation were to evaluate and model the impacts of biologically active filter (biofilter) design and operation on BOM removal as measured by dissolved organic carbon (DOC). Operational and water quality parameters, i.e. extended empty bed contact time (EBCT), temperature, biomass acclimation and distribution, and natural organic matter concentration and origin (microbial, terrestrial and wastewater effluent), were evaluated to determine impacts on biofilter performance. A novel bench scale methodology was developed in Chapter 2 that incorporated a batch reactor and a single-pass flow through reactor that allowed arduous pilot scale experiments to be replaced with streamlined bench scale testing, which could expedite biofilter implementation in drinking water utilities. In Chapter 3, a model derived from Monod kinetics was developed for biological filters based on EBCT and a single biomass measurement from the top of the filter. The model was developed for the control of DOC and successfully applied to predict DOC removal. Biomass activity, adenosine triphosphate (ATP), measurements were a direct function of temperature, yet biomass concentration, phospholipid measurements, were not a function of temperature in the range of 5 °C to 22 °C. Pilot scale work in Chapter 4 found acclimation of the ‘fresh’ media in terms of DOC removal and activity occurred over a two-month time frame. Chapter 4 and Chapter 5 found extended EBCT of a biofilter and higher temperatures improved the performance of biofilters for controlling DOC, yet influent DOC did not impact DOC removal directly. Biomass activity, ATP, was highest at the top of the filter and decreased with increasing filter depth. Chapter 5 bench scale work found biofilters were robust in removing DOC from microbial, terrestrial and wastewater effluent sources and reduced DBP precursors. In chapter 6, a life cycle assessment model was used to compare conventional filtration and biofiltration. Biofiltration had lower environmental impacts than conventional filtration for average U.S. source waters by about 25%. Chemicals, in particular alum and caustic soda, had the largest contributions to environmental impacts. The most effective way to substantially decrease negative environmental impacts of either filtration system is to optimize chemical doses. Higher temperatures can support greater DOC biodegradation, which increases the environmental benefits of biofiltration, and higher levels of… Advisors/Committee Members: R. Scott Summers, Mark Hernandez, Sherri M. Cook, M. Robin Collins, JoAnn Silverstein.

Subjects/Keywords: activity; biofiltration; biomass; empty bed contact time; organic carbon; temperature; Environmental Engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Terry, L. G. (2017). Organic Matter Removal via Biological Drinking Water Filters: Removal Efficiency Based on Quantifiable System Factors. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/cven_gradetds/164

Chicago Manual of Style (16th Edition):

Terry, Leigh Gilmore. “Organic Matter Removal via Biological Drinking Water Filters: Removal Efficiency Based on Quantifiable System Factors.” 2017. Doctoral Dissertation, University of Colorado. Accessed December 14, 2019. https://scholar.colorado.edu/cven_gradetds/164.

MLA Handbook (7th Edition):

Terry, Leigh Gilmore. “Organic Matter Removal via Biological Drinking Water Filters: Removal Efficiency Based on Quantifiable System Factors.” 2017. Web. 14 Dec 2019.

Vancouver:

Terry LG. Organic Matter Removal via Biological Drinking Water Filters: Removal Efficiency Based on Quantifiable System Factors. [Internet] [Doctoral dissertation]. University of Colorado; 2017. [cited 2019 Dec 14]. Available from: https://scholar.colorado.edu/cven_gradetds/164.

Council of Science Editors:

Terry LG. Organic Matter Removal via Biological Drinking Water Filters: Removal Efficiency Based on Quantifiable System Factors. [Doctoral Dissertation]. University of Colorado; 2017. Available from: https://scholar.colorado.edu/cven_gradetds/164

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