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Examining The Relationship Between Lignocellulosic Biomass Structural Constituents And Its Flow Behavior, Ekramul Haque Ehite

Doctoral Dissertations

Lignocellulosic biomass material sourced from plants and herbaceous sources is a promising substrate of inexpensive, abundant, and potentially carbon-neutral energy. One of the leading limitations of using lignocellulosic biomass as a feedstock for bioenergy products is the flow issues encountered during biomass conveyance in biorefineries. In the biorefining process, the biomass feedstock undergoes flow through a variety of conveyance systems. The inherent variability of the feedstock materials, as evidenced by their complex microstructural composition and non-uniform morphology, coupled with the varying flow conditions in the conveyance systems, gives rise to flow issues such as bridging, ratholing, and clogging. These issues …

Understanding Lignin’S Fast Pyrolysis Through Examination Of The Thermolysis Mechanisms Of Model Oligomers, Ross Wesley Houston

Doctoral Dissertations

The lignocellulosic biorefinery is a visionary concept that endeavors to provide an alternative to fossil-based refineries by producing biobased fungible fuels and specialty chemicals almost exclusively derived currently from petroleum refineries. This vision of the lignocellulosic biorefinery can only be realized if all fractions of lignocellulosic biomass are efficiently deconstructed and valorized to generate a diverse portfolio of products to sustain it against market vicissitudes. Of the three main structural constituents of lignocellulosic biomass (i.e., cellulose, hemicellulose, and lignin), lignin is underutilized despite being the most abundant renewable source of aromatic platform chemicals, representing a growing 250 billion dollar market. …

Co2 Adsorption Using Mg-Mof-74/Activated Biochar Composites Produced From The Pyrolysis Of Lignocellulosic Biomass, Conner Brosdan Pope

Masters Theses

Adsorption is a promising carbon capture and storage (CCS) technology with porous solids like activated biochar (AB), graphene oxides (GO), and metal-organic frameworks (MOF) exhibiting different advantages related to separating carbon dioxide (CO₂) from gas mixtures. Accordingly, the synthesis of MOF/GO composites demonstrates synergism between CO₂ adsorption-driving physicochemical characteristics of MOFs and GOs. However, the synthesis of MOF/AB composites has not been explored in the literature to date even though AB shares many physical and chemical similarities with GO. This research project aimed to synthesize MOF/AB composites with appropriate physicochemical characteristics and CO₂ adsorption capacities for …

Sustainable Underground Reactive Barrier To Attenuate Contaminants From Agricultural Drainage, Yuchuan Fan

Doctoral Dissertations

Denitrifying bioreactor (DNBR) has become a popular edge-of-field practice applied to reduce nitrate over the Mississippi river and to prevent a downstream hypoxic zone occurring at the Gulf of Mexico. Despite widespread field and laboratory studies, fewer investigations have been directed toward a systematic means of evaluating the nitrate removal performance achieved by various filling materials, abiotic factors, and other critical parameters. Our ultimate goal is to improve the nitrate removal by choosing the optimum fill materials and operate under optimal conditions, meanwhile, modeling the DNBR by critical variables. This study begins by establishing a global database. Forty filling materials …

Effects Of Soil Conservation Practices On Soil Properties In A Cotton And Soybean System In West Tennessee, Safak Ceylan

Masters Theses

Integration of conservation agriculture practices can provide benefits to crop production. The number of studies focusing on conservation agriculture practices’ effects on sustainable agriculture and environment have increased. In this study, two different experimental field were focused on. In the first one, we evaluated different tillage systems, cover crops and nitrogen fertilizer rates impact on soil properties which are soil total organic carbon (TOC), dissolved organic carbon (DOC), permanganate oxidizable carbon (POXC), total nitrogen (TN) and wet aggregate stability (WAS) under continuous cotton production. The results showed that cover crops were statistically significant in increasing all the properties measured. No-till …

Evaluating The Effects Of Various Painting Techniques On Athletic Field Surface And Root Zone Characteristics, Bryan Mckinley Ogle

Masters Theses

Every year, athletic field marking paint is applied by thousands of turfgrass managers for a range of sports on both natural and synthetic turf athletic fields. Research was conducted to compare different treatments consisting of various nozzle sizes and pressure settings for applying athletic turf paint. Applications occurred eight times, simulating an NCAA football schedule. Treatments were applied in 2015 and 2016 to ‘Tifway 419’ (Cynodon dactylon L.) bermudagrass sod established in 2011 and maintained on a USGA sand-based root zone (United States Golf Association, 2018). Soil samples from each treatment area were subject to analysis consisting of bulk density, …

Volume 16, Number 2 (Fall/Winter 2020), Ut Institute Of Agriculture

Tennessee Land, Life and Science Magazine

Issue Highlights:

• The four pillars of the Institute of Agriculture
• Alumna forges partnership amid Waldo Canyon fire
• Fishery biologists revive a river

Biochar Amendment For Enhanced Nitrogen Use, Soil Health, And Plant Growth, Xiuwen Li

Masters Theses

Biochar is considered as a soil amendment to improve the resilience and productivity of agricultural systems. In particular, co-application of biochar and nitrogen (N) fertilizer has the potential to reduce N losses compared to applying synthetic N alone. However, the positive effects of biochar amendment are tightly linked to several factors. Our overall objective was to determine the effect of biochar types, application methods, and biochar rate on soil health, especially on soil N dynamics, and forage production through bench - and field-scale experiments. A 60-day bench-scale experiment was conducted to study the effect of amending soil with the two …

2019 Eurēca Winners, Office Of Undergraduate Research

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

List of awardees

Improving Water Use Efficiency Of Containerized Crops Using Biochar And Precision Irrigation Scheduling, Nastaran Basiri Jahromi

Doctoral Dissertations

Developing management practices that make more efficient use of irrigation is important for improving the sustainability of agriculture. Biochar, a byproduct of pyrolysis, can potentially increase the amount of available water and improve irrigation efficiency and plant growth. The goal of this study was to evaluate the impact of irrigation schedules and biochar on water use and biomass gain of container crops. Containers were filled with pine bark and amended with 10% or 25% by volume of biochar. Boxwood and hydrangea plants were irrigated when the volumetric water content reached the water buffering capacity set point of 0.25 cm3·cm-3 in …

Understanding And Modeling The Formation Of Syngas Contaminants During Biomass Gasification, Oluwafemi Ademola Oyedeji

Doctoral Dissertations

The focus of this dissertation was to understand and model how inorganic contaminants (mainly H₂S, COS, NH₃, and HCN) are formed during biomass gasification to provide information for effective contaminant abatement and producer gas remediation. This dissertation was partitioned into five research studies with specify objectives. In the first study, a simple thermo-gravimetric approach coupled with CHN analyzer and inductively coupled plasma optical emission spectrometry (ICP-OES) was used to track the conversion profile of C, H, N, S, and O during the pyrolysis stage of biomass gasification. The activation energy for the sulfur and nitrogen conversion …

Biochar Amendment And Moisture Effects On Poultry Litter Windrow Heating Performance, Daihan Wang

Masters Theses

Poultry litter is a key factor that effects broiler (meat chicken) production because it can harbor pathogenic bacteria. Windrowing, which is akin to in-house composting can improve poultry litter quality and limit pathogen growth by heating and drying the litter between flocks. Generally, broiler producers manage windrowing to reach high peak temperatures as fast as possible, to reach efficiently pathogen control standards. Biochar, a carbon rich byproduct of biomass energy production, has the potential to improve windrow heating performance by facilitating higher peak temperature and heating rate. In this study, two sources of biochar as litter amendment prior to windrowing, …

An Analysis Of Consumer Preferences For Gardening Products With Environmentally Friendly Attributes, Mckenzie Lynn Thomas

Masters Theses

Consumers have expressed preferences for gardening products that have environmental benefits or ecofriendly attributes. These products can utilize fewer resources in production, reduce the need for further inputs as well as return nutrients back to the earth. Utilizing a survey of Tennessee indoor and outdoor gardeners, the following two papers estimate how consumer demographics, behaviors and attitudinal variables influence the propensity of a consumer to prefer environmentally friendly gardening products and their use of a specific ecofriendly gardening product, potting mix with biochar.Some key findings from the first paper include that consumer gardening practices and demographic characteristics influence the overall …

Applications Of Optimization Modeling In Multi-Disciplinary Engineering Research, Anton F. Astner, Ekramul Haque Ehite, Yang Li, Colin Sasthav

Biosystems Engineering and Soil Science Publications and Other Works

Optimization modeling is the process of selection of the best solution to a design problem using predetermined constraints from a set of prospective solutions. Increased computing power has made optimization solvers readily available for business/research needs. For example, Microsoft Excel has a simple, but robust solver. Such solvers can model linear, nonlinear, and integer programming problems that are limited in size. This study shows the use of the optimization model solvers in various research contexts.

Feasibility Of Bauxite Residue In Pollution Mitigation And Resource Recovery, Yongfeng Wang

Doctoral Dissertations

Bauxite residue is an industrial waste generated from the alumina refining industry, raising great concerns about environmental pollution. The primary problem for bauxite residue is its high alkalinity and salinity. This beneficial reuse of bauxite residue is desirable for the sustainable management of this waste stream. Bauxite residues can be used as an option of flue gas desulfurization to reduce the toxicity associated with high alkalinity. In this dissertation, it was first identified the linkage between the characteristics of the bauxite residues and their acid neutralization capacity (ANC). Further options of beneficial use were investigated according to the characteristics of …

Mercury Mobilization From Contaminated Creek Bank Soils And Stabilization Using Engineered Sorbents, Leroy Goñez Rodríguez

Masters Theses

As a global environmental pollutant, mercury (Hg), threatens our water resources and presents a substantial risk to human health. The goal of this research project was to evaluate the immobilization of Hg on sorbents to reduce ambient Hg concentrations in water leaching from contaminated East Fork Poplar Creek (EFPC) (Oak Ridge, TN, USA) soils. Using flow-through columns, we determined the potential of different kinds of engineered sorbents (i.e., ThiolSAMMS®, biochar, SediMiteTM, OrganoclayTM PM199) to reduce mercury fluxes from contaminated EFPC soils. The effectiveness of the sorbents in this experiment was determined based on the rate of Hg sorbed and the …

Computational Fluid Dynamic Modeling Of Catalytic Hydrous Pyrolysis Of Biomass To Produce Refinery-Ready Bio-Crude Oil, Ross Wesley Houston

Masters Theses

The growing world population continually increases the demand for energy. Currently, the main source of energy production is fossil fuels, which are harmful to the environment and are finite. An exploration of renewable energy to supplement or replace fossil fuels is of great importance. Modern techniques for producing renewable bio-oil consist of converting biomass into bio-oil through pyrolysis, but unfortunately, pyrolysis oil has quality issues (e.g., high oxygen content, viscosity, chemical instability). Therefore, upgrading is necessary to improve quality. Hydropyrolysis is a state of the art technique to deoxygenate bio-oil during pyrolysis to produce petroleum quality bio-oil. A major issue …

Sustainable Method For Recovery Of Copper Naphthenate From Used Railroad Ties, Holly Lauren Haber

Masters Theses

Recovery of the wood preservative copper naphthenate (CN) from end-of-life railroad ties was investigated to promote the secondary use of this biomass as a fuel source and mitigate the negative impacts of landfilling and other alternative tie disposal methods. Thermal desorption of naphthenic acids from CN-treated ties preceded inorganic extraction with ethylenediaminetetraacetic acid (EDTA) and biodegradable chelating agents, 2,6-pyridine dicarboxylic acid (PDA) and 1-hydroxy ethylidene-1,1-disphosphonic acid (HEDP). Organic preservative components were recovered from thermal pretreatment at temperatures between 225 and 300 °C. This thermal desorption also mirrored torrefaction by increasing the ties’ higher heating value and carbon content, in addition …

2017 Eurēca Abstract Book, Office Of Undergraduate Research

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

Listing of student participant abstracts.

Impact Of Soil Water Content On Bermudagrass Athletic Field Performance, Kyley Hampton Dickson

Doctoral Dissertations

Soil water content (SWC) influences the consistency and performance of athletic fields. Two studies were conducted at the University of Tennessee Center for Athletic Field Safety (Knoxville, TN) to determine SWC impact on the performance of hybrid bermudagrass [Cynodon dactylon (L.) Pers. x C. transvaalensis, Burtt-Davy, ‘Tifway’] on silt loam (cohesive) and sand root zone conforming to United States Golf Association (USGA) specifications (noncohesive) root zones. Soil water content treatments for the cohesive soil averaged 0.10 m³/m³ (+/- 0.035), 0.17 m³/m³ (+/- 0.035), 0.26 m³/m³ (+/- 0.035), and 0.35 …

Pretreatment And Posttreatment Approaches For Reducing Biomass Inorganic Impurities During Gasification, Qiaoming Liu

Masters Theses

During gasification, biomass can be thermally decomposed into a mixture of combustible gases known collectively as syngas to produce heat, power, and liquid fuels in downstream processes. However, inorganic elements, present in biomass and released into syngas as impurities, are considered one of the main deterrent to the commercial deployment of biomass gasification technologies and have recently contributed to the failure of a thermochemical biorefinery. In conventional gasification installations, a syngas cleanup process area, which comprises a combination of processes, is used to reduce the concentrations of these inorganic impurities below tolerable limits.

In recent years, several treatment approaches have …

Managing Exoelectrogenic Microbial Community Development Through Bioprocess Control For Conversion Of Biomass-Derived Streams, Alex James Lewis

Doctoral Dissertations

Bioelectrochemical systems are an emerging technology capable of utilizing aqueous waste streams generated during biomass conversion of lignocellulosic feedstocks to produce valuable co-products and thus, have potential to be integrated into biorefineries. In a microbial electrolysis cell, organic compounds are converted to electrons, protons, and CO₂ by fermentative and exoelectrogenic bacteria in the anode compartment. By having the ability to extract electrons from waste streams, these systems can treat water while also producing hydrogen, and thus can improve the efficiency of biomass to fuel production by minimizing external hydrogen requirement and enabling water recycle. The overall goal of this …

2017 Eurēca Winners, Office Of Undergraduate Research

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

List of awardees

Characterization Of Fusarium Species And Alternaria Alternata, And Their Effects On Switchgrass Health And Chemical Components, Sara Beth Collins

Masters Theses

Panicum virgatum L., readily referred to as Switchgrass, is a perennial warm-season bunch grass, used as an alternative energy source for biofuel production. There is insufficient research on switchgrass pathogens, and is expected that an increase in disease pressure will result as more land is reserved for this perennial crop. The purpose of this research was to identify and characterize pathogenic Alternaria alternata and Fusarium species on Switchgrass (Panicum virgatum L.), and to evaluate their impact on stand establishment and plant health. Molecular identifications of fungal isolates obtained from infected commercial switchgrass seed yielded eight species (A. alternata, …

Cassava (Manihot Esculenta Crantz) Tuber Quality As Measured By Starch And Cyanide (Hcn) Affected By Nitrogen, Phosphorus, And Potassium Fertilizer Rates, Ivan Bernardo Cuvaca, Neal Eash, Svetlana Zivanovic, Dayton Mcgregor Lambert, Forbes R. Walker, B. Rustrick

Biosystems Engineering and Soil Science Publications and Other Works

Cassava (Manihot esculenta Crantz) is an important subsistence crop for many poor rural families in Africa. Cassava contains cyanogenic glucosides (linamarin and lotaustralin) which liberate hydrogen cyanide (HCN) during tuber processing. Once liberated, HCN attaches to the processed tuber. Continuous consumption of processed tuber containing high HCN concentration coupled with low protein intake causes Konzo – a paralyzing disorder that impacts children and women of childbearing age. There are ways to reduce HCN concentration during tuber processing; however, this can also reduce the overall starch content in the cassava tuber. A study comprising twenty treatments consisting of different combinations of …

Enhancing The Sustainability Of Integrated Biofuel Feedstock Production Systems, Amanda Joy Ashworth

Doctoral Dissertations

As use of second-generation biofuel crops increases, so do questions about sustainability, particularly their potential to affect fossil energy consumption and greenhouse gas emissions. Nitrogen (N)-fixing legumes interseeded into switchgrass (Panicum virgatum L.) may be an alternative to inorganic fertilizer in forage-feedstock systems. Research herein is divided into four general experiments: I). N replacement and feedstock impacts from legume intercrops and biochar in switchgrass; II). N-fixation rates in intercrop systems; III). impacts of biofuel systems under enhanced climate change; and, IV). projected sustainability of regional switchgrass production. Approaches included: characterization of feedstock/forage quality traits based on legume, biochar and …

Influence Of Pyrolysis Temperature And Production Conditions On Switchgrass Biochar For Use As A Soil Amendment, Amanda Joy Ashworth, Samy Sadaka, Fred L. Allen, Mahmoud A. Sharara, Patrick D. Keyser

Plant Sciences Publications and Other Works

Biochars form recalcitrant carbon and increase water and nutrient retention in soils; however, the magnitude is contingent upon production conditions and thermo-chemical conversion processes. Herein we aim at (i) characterizing switchgrass (Panicum virgatum L.)-biochar morphology, (ii) estimating water-holding capacity under increasing ratios of char: soil; and, (iii) determining nutrient profile variation as a function of pyrolysis conversion methodologies (i.e. continuous, auger pyrolysis system versus batch pyrolysis systems) for terminal use as a soil amendment. Auger system chars produced at 600 °C had the greatest lignin portion by weight among the biochars produced from the continuous system. On …

Characterization Of Biochar From Switchgrass Carbonization, Samy Sadaka, Mahmoud A. Sharara, Amanda Ashworth, Patrick D. Keyser, Fred Allen, Andrew Wright

UT Extension publication

Switchgrass is a high yielding, low-input intensive, native perennial grass that has been promoted as a major second-generation bioenergy crop. Raw switchgrass is not a readily acceptable feedstock in existing power plants that were built to accommodate coal and peat. The objective of this research was to elucidate some of the characteristics of switchgrass biochar produced via carbonization and to explore its potential use as a solid fuel. Samples were carbonized in a batch reactor under reactor temperatures of 300, 350 and 400 °C for 1, 2 and 3 h residence times. Biochar mass yield and volatile solids decreased from …

Fate And Transport Of 17beta-Estradiol Beneath Animal Waste Holding Ponds, Lori A. Gibson

Masters Theses

Steroidal hormones, such as 17beta-estradiol (E2) and its primary metabolite, estrone (E1), are prevalent in animal waste and are a common subject of study due to potential soil, stream, and groundwater contamination. These particular hormones are labeled as Endocrine Disrupting Chemicals (EDCs) because of their developmental effects in reptiles and amphibians. Dairy waste at concentrated animal feeding operations (CAFOs) is typically stored in a waste pond. Even though these waste ponds are regulated to include a soil liner with a minimal hydraulic conductivity to limit leaching, previous studies have traced stream and groundwater contamination from waste ponds. This research included …

The Effects Of Biochar Amendment To Soil On Bioenergy Crop Yield And Biomass Composition, Charles Warren Edmunds

Masters Theses

This thesis research aims to improve the understanding of how pyrolysis of native feedstocks and biochar application to soil can be utilized to improve soil fertility, crop yield, and sequester carbon in the Southeastern U.S. An emphasis was placed on understanding how the pyrolysis conditions and feedstock material influence biochar characteristics and what effects biochar amendment has on soil and plant growth and composition.

Biochars were produced from switchgrass and pine wood feedstocks via fast pyrolysis at 450, 600, and 800 ˚C with a continuous auger pyrolysis system. Switchgrass-derived biochars had higher ash content, and as observed by elemental analysis, …