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- Anaerobic Digestion (4)
- Biosolids (4)
- Anaerobic digestion (2)
- Arsenic (2)
- Bioaugmentation (2)
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- Biochar (2)
- Ion Exchange (2)
- Microbial Community (2)
- Microbial community structure (2)
- Micropollutants (2)
- Phosphorus (2)
- Pyrolysis (2)
- Triclosan (2)
- Wastewater (2)
- Activated Carbon;DBPs;Membrane;Nanofiltration;Porosity;Regeneration (1)
- Ammonia Toxicity (1)
- Ammonia toxicity (1)
- Ammonium (1)
- Amplicon sequencing (1)
- Anaerobic (1)
- Aqueous phase (1)
- Autocatalysis (1)
- Bio-oil (1)
- CFD Modeling (1)
- Chromium (1)
- Clarification (1)
- Coal Gasification (1)
- Denaturing gradient gel electrophoresis (1)
- Dewaterability (1)
- Drying (1)
Articles 1 - 20 of 20
Full-Text Articles in Engineering
The Role Of Membrane Porosity In Ion Removal By Ro/Nf Membranes And Development Of A Regenerable Pac-Loaded Membrane, Yizhi Hou
Dissertations (1934 -)
Reverse osmosis (RO) and nanofiltration (NF) membranes are widely used for water treatment applications. They are charged porous materials, in which size exclusion and charge exclusion work together to dictate solute transport. In this study, membrane porosity was primarily determined by pore size. Thicker, more porous membranes with smaller pores had higher NaCl removal and less permeate water flux. Higher porosity membranes have greater inner pore surface area available to support a greater number of functional groups, thereby rejecting ion flux and increasing ion removal. The Donnan steric pore model (DSPM) was used to determine that the contribution of diffusion …
Effect Of Low Aeration And Heat Drying On Anaerobic Digester Performance And Microbial Community, Dylan Thomas Friss
Effect Of Low Aeration And Heat Drying On Anaerobic Digester Performance And Microbial Community, Dylan Thomas Friss
Master's Theses (2009 -)
This thesis describes three research projects on anaerobic digestion (AD) that investigated functional differences and relationships between microbial composition and digester function. Both archaeal and bacterial communities were characterized using high throughput (Illumina) sequencing technology with universal 16S rRNA gene primers. In the first project, limited aeration, and limited aeration with an aerotolerant enrichment culture were investigated as possible methods to increase digester functional performance in comparison to a strictly anaerobic control digester. No functional differences were observed at quasi-steady state between the limited aerated digester (LAD), limited aerated anaerobic digester augmented with an aerotolerant enrichment culture (LADE), and strictly …
Micropollutant-Free Nutrient Recovery: Adsorption Of Micropollutants On Ion Exchangers And Biosolids-Derived Biochar, Yiran Tong
Dissertations (1934 -)
The presence of excessive nutrients in treated wastewater effluent is a growing concern in terms of water quality and ecological balance. Thus, removal of nutrients is of great interest. Moreover, the removed nutrients can be recovered in forms amenable for agricultural reuse, which yields a sustainable supply of nonrenewable phosphorus that can be used to support global food production. As nutrient recovery gains interest, it is essential that the products be free of harmful contaminants. One class of contaminants of great concern is organic micropollutants. To help address these issues, this study evaluated the fate and impact of micropollutants during …
Anaerobic Co-Digestion Of Aqueous Liquid From Biosolids Pyrolysis, Seyedfatemeh Seyedi
Anaerobic Co-Digestion Of Aqueous Liquid From Biosolids Pyrolysis, Seyedfatemeh Seyedi
Master's Theses (2009 -)
Pyrolysis is a process to treat biosolids and recover energy. During pyrolysis, conversion of organic matter to energy-rich products yields biochar, py-gas, and pyrolysis liquids (aqueous phase and non-aqueous bio-oil). The aqueous pyrolysis liquid (APL), is a high-COD liquid with no apparent use that contains polycyclic aromatic hydrocarbons and nitrogen-containing compounds. One potential beneficial use of APL is as a co-digestate to produce more biogas for renewable energy from anaerobic digesters at municipal water resource recovery facilities. Some of the organics in APL may be converted to biomethane via anaerobic digestion under proper conditions. However, some APL organics are known …
The Impact Of Phosphorous Species On Dewaterability Of Wastewater Solids, Erik Anderson
The Impact Of Phosphorous Species On Dewaterability Of Wastewater Solids, Erik Anderson
Master's Theses (2009 -)
Phosphorus regulations are causing Water Resource Recovery Facilities (WRRFs) to implement new technologies to remove phosphorus (P) before they discharge liquid effluent. Enhanced Biological Phosphorus Removal (EBPR) is often employed to remove P from water. However, sludges from EBPR plants have shown decreases in dewaterability soon after EBPR was initiated. This decline in dewaterability is not well understood, nor is the best way to improve the dewatering EBPR sludge. Specifically, the role of different P species on sludge dewaterability is not well understood. Several laboratory experiments were conducted at the Marquette University Water Quality Center with the following objectives: i) …
An Improved Method Of Arsenic (Iii) Removal By Reverse Osmosis Membrane, Yizhi Hou
An Improved Method Of Arsenic (Iii) Removal By Reverse Osmosis Membrane, Yizhi Hou
Master's Theses (2009 -)
Arsenic is a Group 1 carcinogen as there is abundant research to support that ingestion of arsenic in drinking water and food can lead to liver, lung, kidney, or bladder cancer in humans. The recommend World Health Organization (WHO) arsenic standard in drinking water is 10 µg/L, while the Environmental Protection Agency's (EPA) Maximum Contaminant Level (MCL) of arsenic in drinking water is 10 µg/L. Globally, at least 40 million people face more than 10 µg/L arsenic contamination in their drinking water. As(III) (trivalent state, such as arsenite), and As(V) (pentavalent state, such as arsenates) are the dominant arsenic forms …
Pore Resolved Simulations Of Char Particle Gasification, Greg Hingwah Fong
Pore Resolved Simulations Of Char Particle Gasification, Greg Hingwah Fong
Master's Theses (2009 -)
Coal is a significant source of energy in today’s world and many studies have been conducted in order to better understand and optimize its use. To address greenhouse effects associated with coal combustion, cleaner methods for harnessing its energy are being explored. One such method is gasification, a process which converts coal into syngas, a mixture consisting primarily of H2 and CO. Syngas can be used to generate electricity or to produce hydrocarbons that can be used as fuels. To better understand and optimize the process, simulations can be used to study the gasification of individual porous char particles that …
Biosolids-Derived Biochar For Micropollutant Removal From Wastewater, Lee Kimbell
Biosolids-Derived Biochar For Micropollutant Removal From Wastewater, Lee Kimbell
Master's Theses (2009 -)
Trace organic compounds including antibiotics, hormones, pharmaceuticals and personal care products are discharged to the environment with liquid and solid effluent streams from water resource recovery facilities. These compounds are referred to as micropollutants, and can have negative impacts in receiving waters. Current wastewater treatment processes are not specifically designed to remove micropollutants, and many of these compounds are recalcitrant to conventional treatment technologies. Triclosan (TCS) was selected as a representative micropollutant in this study due to frequent detection in liquid effluents, residual biosolids, and surface waters. Pyrolysis - the thermochemical decomposition of organic matter at elevated temperatures in the …
Bioaugmentation And Correlating Anaerobic Digester Microbial Community To Process Function, Kaushik Venkiteshwaran
Bioaugmentation And Correlating Anaerobic Digester Microbial Community To Process Function, Kaushik Venkiteshwaran
Dissertations (1934 -)
This dissertation describes two research projects on anaerobic digestion (AD) that investigated the relationship between microbial community structure and digester function. Both archaeal and bacterial communities were characterized using high-throughput (Illumina) sequencing technology with universal 16S rRNA gene primers. In the first project, bioaugmentation using a methanogenic, aerotolerant propionate enrichment culture was investigated as a possible method to increase digester methane production. Nine anaerobic digesters, seeded with different biomass, were operated identically and their quasi steady state function was compared. Before bioaugmentation, different seed biomass resulted in different quasi steady state function, with digesters clustering into high, medium or low …
The Role Of Household Antimicrobials In The Proliferation Of Antibiotic Resistance During Anaerobic Digestion, Daniel Elliott Carey
The Role Of Household Antimicrobials In The Proliferation Of Antibiotic Resistance During Anaerobic Digestion, Daniel Elliott Carey
Dissertations (1934 -)
Antimicrobial chemicals in consumer personal care products have been found to increase antibiotic resistance in pure culture studies. Although many studies focus on antibiotic resistance development pertinent to medical scenarios, resistance developed in natural and engineered environments might be significant and has become an emerging concern for human health. This dissertation focuses on the antimicrobial chemicals triclosan and triclocarban. These compounds are distinctly different from antibiotics and are used in products like soaps that are labelled as “antibacterial”. Municipal wastewater treatment plants receive triclocarban and triclosan loads higher than most contaminants of emerging concern because they are frequently used in …
The Contribution Of Syntrophic Fatty-Acid Degrading Microbial Communities To Anaerobic Digester Function And Stability, Prince Peter Mathai
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 …
Municipal Wastewater Anaerobic Treatment With Enhanced Clarification, Kevin Berg
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 …
Removal Of Trace Heavy Metals From Drinking Water By Electrocoagulation, Joe Heffron
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 …
Pyrolysis For Estrogens Removal From Wastewater Solids, Thomas C. Hoffman
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
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 …
Fate Of Micropollutants During Pyrolysis Of Biosolids, John Ross
Fate Of Micropollutants During Pyrolysis Of Biosolids, John Ross
Master's Theses (2009 -)
Approximately 250 tons of organic micropollutants, including pharmaceuticals, antimicrobials, and hormones, are discharged to the environment during land application of wastewater biosolids annually. Reusing wastewater biosolids is vital to the sustainability of wastewater treatment, but current treatment processes do not remove micropollutants from biosolids in an efficient manner. Pyrolysis―the heating of biomass to temperatures between 400 and 800 °C under oxygen-free conditions―was proposed as a biosolids treatment process that could produce a beneficial soil amendment product, biochar, and remove micropollutants. The objective of this research was to determine the effect of pyrolysis temperature and residence time on the removal of …
Anaerobic Co-Digestion Planning And Research For Green Bay, Wi, Jonathan Kusowski
Anaerobic Co-Digestion Planning And Research For Green Bay, Wi, Jonathan Kusowski
Master's Theses (2009 -)
The aspiration to find an alternative sustainable fuel source is an ever growing concern. Anaerobic digestion might hold the answer to finding an alternative sustainable energy source. Anaerobic digestion does not only provide a renewable resource in the form of biogas, but also stabilizes wastes, preventing large amounts from being landfilled or incinerated. Anaerobic digestion of municipal wastewater sludges can often be improved by the addition of high strength industrial wastes, in a process called co-digestion. High strength industrial wastes provide an additional carbon source for the microbes to utilize and convert into usable biogas. Co-digestion also offers the opportunity …
Ion Exchange Nutrient Recovery From Municipal Wastewater, Allen Williams
Ion Exchange Nutrient Recovery From Municipal Wastewater, Allen Williams
Master's Theses (2009 -)
Nitrogen and phosphorus discharge is regulated due to eutrophication. Typically ammonium-nitrogen is removed through nitrification which requires energy and phosphorus (P) is removed by metal salt addition to precipitate P. A more sustainable approach may be to implement nutrient recovery to form fertilizers. Most nitrogen fertilizer is formed through the energy intensive Haber-Bosch process. Phosphate rock, a limited resource, is mined for P fertilizer. Discharge regulations and the fertilizer production costs provide an economic driver for recovery. The current project used anionic and cationic ion exchange (IX) to concentrate the nutrients with recovery by struvite precipitation. Previous work lacks direct …
Relating Methanogen Community Structure And Function In Anaerobic Digesters, Benjamin T.W. Bocher
Relating Methanogen Community Structure And Function In Anaerobic Digesters, Benjamin T.W. Bocher
Dissertations (1934 -)
A deeper understanding of how microbial community structure relates to process function would help improve anaerobic digester design. This dissertation describes both qualitative and quantitative relationships between anaerobic digester function and microbial community structure. Community structure was characterized using banding pattern intensities from denaturing gradient gel electrophoresis (DGGE) for the mcrA gene of methanogenic Archaea. The first project compared a single-stage continuously mixed stirred tank reactor (CSTR) and staging with an acidogenic CSTR followed by a methanogenic CSTR. After seeding with the same biomass, these unique process configurations exhibited different function and qualitatively different methanogen communities. Compared to a single-stage …
Preservation Of Methanogenic Cultures To Enhance Anaerobic Digestion, Ujwal H. Bhattad
Preservation Of Methanogenic Cultures To Enhance Anaerobic Digestion, Ujwal H. Bhattad
Dissertations (1934 -)
The use of anaerobic biotechnology is increasing as a sustainable process to treat various organic wastes. Methanogens convert organic COD into CH4 and play the key role to drive thermodynamically unfavorable biochemical fermentation reactions and keep the digestion process steady and efficient. Progressive understanding of anaerobic microbiology with digester functionality may help to develop efficient, customized methanogenic cultures to enhance anaerobic bioprocesses. Preservation of methanogenic cultures via drying would be a cost-effective option for research and practical applications. However, preservation of methanogenic cultures is challenging due to methanogen sensitivity to O2 toxicity and drying, and very limited work is reported …