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Articles 91 - 120 of 164
Full-Text Articles in Environmental Engineering
Influence Of Coal-Fired Power Plant Emissions Regulations And Consequent Engineering Controls And Coal-Supply Modifications On Fly Ash Chemistry And Petrology: Examples From Kentucky Power Plants, Madison M. Hood, John G. Groppo, Michelle N. Johnston, James C. Hower, Herek L. Clack, Diego S. De Medeiros, Silvio R. Taffarel, Cesar M.N.L. Cutruneo, Luis F.O. Silva
Influence Of Coal-Fired Power Plant Emissions Regulations And Consequent Engineering Controls And Coal-Supply Modifications On Fly Ash Chemistry And Petrology: Examples From Kentucky Power Plants, Madison M. Hood, John G. Groppo, Michelle N. Johnston, James C. Hower, Herek L. Clack, Diego S. De Medeiros, Silvio R. Taffarel, Cesar M.N.L. Cutruneo, Luis F.O. Silva
Coal Combustion and Gasification Products Journal Archive
The chemistry and petrology of fly ash are controlled by a number of factors: (1) chemistry of the feed coal (and added fuels, such as petroleum coke, tires, biomass, etc.), (2) particle size of the fuel feed (controlled by pulverized fuel vs. cyclone combustion, maintenance of pulverizers, etc.), (3) design of the boiler and pollution-control system, and (4) temperature of the flue gas at the collection point. In general, for any electrostatic precipitator or baghouse system, the concentrations of volatile trace elements in fly ash will increase with a drop in the flue gas temperature and a decrease in the …
Long-Term Effects Of Forestry Best Management Practices On Hydrology And Water Chemistry In Three Appalchian Headwater Catchments, Kameryn I. Wright
Long-Term Effects Of Forestry Best Management Practices On Hydrology And Water Chemistry In Three Appalchian Headwater Catchments, Kameryn I. Wright
Theses and Dissertations--Biosystems and Agricultural Engineering
In 1982, a study was initiated in the Field Branch watershed, in the University of Kentucky’s Robinson Forest, to evaluate forestry best management practice (BMP) effectiveness after intensive harvesting. The study utilized a paired watershed approach on three adjacent Field Branch subcatchments. One subcatchment was left as the control, one had BMPs implemented (including a 50-ft undisturbed buffer along the stream), and one was clear-cut to the stream’s banks without the use of BMPs (i.e. logger’s choice). Prior research has shown that logging can negatively impact watershed functions by altering stream hydrology, geomorphology, water quality, and instream habitat. Thus, the …
Development Of Regional And Hydraulic Geometry Curves For The Eastern Kentucky Coalfields, Ashlan Berry
Development Of Regional And Hydraulic Geometry Curves For The Eastern Kentucky Coalfields, Ashlan Berry
Theses and Dissertations--Biosystems and Agricultural Engineering
Regional curves and hydraulic geometry curves relate bankfull channel dimensions to drainage area and bankfull discharge, respectively. These curves are used in the natural channel design process to help identify bankfull and to estimate bankfull dimensions of the design channel. Nineteen streams were surveyed to determine their bankfull parameters (cross-sectional area, width, mean depth, discharge, slope, and Manning’s n), along with 27 streams previously surveyed in other studies. The data were used to create regional and hydraulic geometry curves for three hydrologic landscape regions (HLR 9, HLR 11, and HLR 16, individually) in the Eastern Kentucky Coalfields (EKC) as well …
Heterogeneous Oxidation Of Catechol, Elizabeth A. Pillar, Ruixin Zhou, Marcelo I. Guzman
Heterogeneous Oxidation Of Catechol, Elizabeth A. Pillar, Ruixin Zhou, Marcelo I. Guzman
Chemistry Faculty Publications
Natural and anthropogenic emissions of aromatic hydrocarbons from biomass burning, agro-industrial settings, and fossil fuel combustion contribute precursors to secondary aerosol formation (SOA). How these compounds are processed under humid tropospheric conditions is the focus of current attention to understand their environmental fate. This work shows how catechol thin films, a model for oxygenated aromatic hydrocarbons present in biomass burning and combustion aerosols, undergo heterogeneous oxidation at the air–solid interface under variable relative humidity (RH = 0–90%). The maximum reactive uptake coefficient of O3(g) by catechol γO3 = (7.49 ± 0.35) × 10–6 occurs for …
Secondary Organic Aerosol Formation From The Β-Pinene+No3 System: Effect Of Humidity And Peroxy Radical Fate, C. M. Boyd, J. Sanchez, L. Xu, Alexis J. Eugene, T. Nah, W. Y. Tuet, Marcelo I. Guzman, N. L. Ng
Secondary Organic Aerosol Formation From The Β-Pinene+No3 System: Effect Of Humidity And Peroxy Radical Fate, C. M. Boyd, J. Sanchez, L. Xu, Alexis J. Eugene, T. Nah, W. Y. Tuet, Marcelo I. Guzman, N. L. Ng
Chemistry Faculty Publications
The formation of secondary organic aerosol (SOA) from the oxidation of β-pinene via nitrate radicals is investigated in the Georgia Tech Environmental Chamber (GTEC) facility. Aerosol yields are determined for experiments performed under both dry (relative humidity (RH) < 2 %) and humid (RH = 50 % and RH = 70 %) conditions. To probe the effects of peroxy radical (RO2) fate on aerosol formation, "RO2 + NO3 dominant" and "RO2 + HO2 dominant" experiments are performed. Gas-phase organic nitrate species (with molecular weights of 215, 229, 231, and 245 amu, which likely correspond to molecular formulas of C10H17NO4, C10H15NO5, C10H17NO …
Multistage Concentration Of Cenospheres In Fly Ash Using The Inverted Reflux Classifier, A. Kiani, J. Zhou, K.P. Galvin
Multistage Concentration Of Cenospheres In Fly Ash Using The Inverted Reflux Classifier, A. Kiani, J. Zhou, K.P. Galvin
Coal Combustion and Gasification Products Journal Archive
Cenospheres are one of the most valuable components found in the fly ash waste of coal-fired power stations, consisting of hollow, aluminosilicate spherical shells and offering very low bulk density, high strength, and high thermal resistance. Although wet processing methods offer the best prospect for achieving recovery and concentration of the cenospheres, significant impediments remain for achieving satisfactory economics. This work was concerned with the recovery and concentration of cenospheres from fly ash using a novel system, the inverted reflux classifier (IRC), covering single and multistage processing. The system consists of a series of parallel inclined channels mounted underneath an …
Strengthening Black Cotton Soil With Fly Ash And Moorum: An Investigation Of The Role Of Subgrade And Subbase Layers, Gourav Saxena, Nikhlesh Chaurasia
Strengthening Black Cotton Soil With Fly Ash And Moorum: An Investigation Of The Role Of Subgrade And Subbase Layers, Gourav Saxena, Nikhlesh Chaurasia
Coal Combustion and Gasification Products Journal Archive
One of the most effective and economical methods to strengthen clayey soils is addition of stabilizing agents such as fly ash to the soil. In this study, highly plastic clay was stabilized using fly ash. Geotechnical properties such as Atterberg limits, unconfined compressive strength (UCS), and the California bearing ratio (CBR) value of virgin black cotton soil and soil treated with fly ash were evaluated. Soil was stabilized with various proportions of fly ash, i.e., at 0%, 10%, 15%, 20%, and 30%. The UCS of black cotton soil–fly ash mixes is found to be at its maximum at 20% fly …
Using Coal Fly Ash In Agriculture: Combination Of Fly Ash And Poultry Litter As Soil Amendments For Bioenergy Feedstock Production, E. Kudjo Dzantor, Ekundayo Adeleke, Vanaha Kankarla, Oluwatosin Ogunmayowa, Dafeng Hui
Using Coal Fly Ash In Agriculture: Combination Of Fly Ash And Poultry Litter As Soil Amendments For Bioenergy Feedstock Production, E. Kudjo Dzantor, Ekundayo Adeleke, Vanaha Kankarla, Oluwatosin Ogunmayowa, Dafeng Hui
Coal Combustion and Gasification Products Journal Archive
Increasing fiscal, human, and environmental costs of coal fly ash (FA) management are leading to advocacy for greater beneficial uses of the by-products as soil amendments in agriculture. Greenhouse experiments were conducted in Armour silt loam (ASL) soil that was amended with FA (10%, wt/wt) with and without poultry litter (PL 5 75 mg N/kg). Biomass productivity of eastern gamagrass (GG), a warm-season perennial grass, was measured to serve as complementary biofuel feedstock to switchgrass (SG). FA was obtained from a site at the 2008 ash spill in Kingston, TN. GG and SG were grown individually in 15-cm-wide 3 41-cm-high …
Fabrication And Testing Of Low-Energy Calcium Sulfoaluminate-Belite Cements That Utilize Circulating Fluidized Bed Combustion By-Products, Robert Jewell, Robert Rathbone, Tristana Duvallet, Thomas Robl, Kamyar Mahboub
Fabrication And Testing Of Low-Energy Calcium Sulfoaluminate-Belite Cements That Utilize Circulating Fluidized Bed Combustion By-Products, Robert Jewell, Robert Rathbone, Tristana Duvallet, Thomas Robl, Kamyar Mahboub
Coal Combustion and Gasification Products Journal Archive
The utilization of circulating fluidized bed combustion (CFBC) ash to make cement products that provide added value and offset CO2 production is the objective of this research. CFBC burns coal in the presence of a bed of slaked limestone, which effectively absorbs sulfur dioxide (SO2) to form anhydrite (CaSO4). CFBC produces two kinds of spent bed materials, coarse bottom ash and a much finer fly ash. Both of these products are very high in calcium. When properly conditioned, these materials are capable of acting as hydraulic cements, forming both calcium aluminosulfate minerals, most importantly ettringite, as well as calcium-alumina-silica gels, …
Prediction Of The Unburned Carbon Content Of Fly Ash In Coal-Fired Power Plants, Saeid R. Dindarloo, James C. Hower
Prediction Of The Unburned Carbon Content Of Fly Ash In Coal-Fired Power Plants, Saeid R. Dindarloo, James C. Hower
Coal Combustion and Gasification Products Journal Archive
Prediction of carbon content in fly ash is a valuable index in both designing and optimizing coal-fired boilers. In this study, methods of multiple regression (MR), decision trees (DT), and support vector regression (SVR) were used for prediction of unburned carbon content of fly ash in a 300-MW power plant with a tangentially fired furnace using a low-NOx concentric firing system. Twenty-one boiler operational and coal petrological variables from 21 experiments in a previous benchmark study were used. A variables correlation matrix was used for feature (independent variables) selection in order to reduce the dimensions (number) of input variables from …
Recycling Of Lignite Coal Fly Ash By Its Conversion Into Zeolites, Silviya Boycheva, Denitza Zgureva, Annie Shoumkova
Recycling Of Lignite Coal Fly Ash By Its Conversion Into Zeolites, Silviya Boycheva, Denitza Zgureva, Annie Shoumkova
Coal Combustion and Gasification Products Journal Archive
The present study emphasized the conversion of fly ash from lignite coals into zeolites by a double-stage fusion-hydrothermal synthesis. The raw and the converted fly ashes were characterized with respect to their morphology, composition, and crystallinity. The effects of process parameters such as fusion temperature, concentration of the alkaline activator, and the duration of the hydrothermal incubation on the zeolitization process were studied. The experimental results indicate that the fusion temperature does not influence the process mechanism in the range 550–850uC, but it has an acceleration effect. The elevation of the sodium hydroxide/fly ash ratio from 1.6 to 2.0 enhances …
Sustainable Disposal Of Coal Processing Waste Streams, Mohammad Rezaee
Sustainable Disposal Of Coal Processing Waste Streams, Mohammad Rezaee
Theses and Dissertations--Mining Engineering
Modern coal preparation facilities incorporate a wide array of solid-solid and solid-liquid separation processes for rejecting mineral matter to meet market specifications. The coarse mineral matter is typically placed into engineered refuse piles whereas the fine refuse is either stored in impoundments or co-disposed with the coarse refuse. The discharge water from the refuse material represents an environmental concern due to the potential release of trace elements, and the subsequent elevation of total dissolved solids and conductivity. The research findings reported in this dissertation addresses sustainable coal processing waste disposal through using strategies aimed at minimizing the environmental impacts. To …
Determining Soil Erosion With Varying Corn Stover Cover Factors, Nicole K. Koeninger
Determining Soil Erosion With Varying Corn Stover Cover Factors, Nicole K. Koeninger
Theses and Dissertations--Biosystems and Agricultural Engineering
Since the Dust Bowl, conservation agriculture has become a common practice globally. Because of the rising interest in the use of corn biomass as a feedstock for biofuel production, the effects of corn stover removal on soil erosion were explored. It was hypothesized that selective harvesting strategies would impact soil erosion differently across a variety of slopes. Soil erosion boxes were constructed, and a rainfall simulator with an intensity of 30 mm hr-1 for 46 min was used to create runoff from slopes of 1, 5, and 10% and three cover factor treatments (no removal and two simulated corn …
Development Of Techniques For Assessing And Restoring Streams On Surface Mined Lands, Whitney Cole Blackburn-Lynch
Development Of Techniques For Assessing And Restoring Streams On Surface Mined Lands, Whitney Cole Blackburn-Lynch
Theses and Dissertations--Biosystems and Agricultural Engineering
Surface mining is a commonly used method for extracting coal in the Appalachian Coalfields of the U.S. This mining practice produces excess spoil or overburden, which is often placed in adjacent valleys resulting in the creation of valley fills. These valley fills bury headwater streams, which in turn can negatively impact downstream ecosystems. In 2008, the University of Kentucky designed and constructed 1,020 m of ephemeral, intermittent and headwater streams on an existing valley fill (Guy Cove) as a proof-of-concept. The goal of the project was to evaluate whether or not a stream recreation could occur on mined lands, particularly …
Characterization Of Two Biochars Derived From Horse Muck And Their Ability To Reduce Pathogen Transport In Soil, David Griffith
Characterization Of Two Biochars Derived From Horse Muck And Their Ability To Reduce Pathogen Transport In Soil, David Griffith
Theses and Dissertations--Biosystems and Agricultural Engineering
Biochars have been created and characterized from a variety livestock manure biomass including poultry, dairy, and swine. However, no research has been conducted on the physical and chemical makeup of biochar pyrolyzed from horse muck. Two horse muck derived biochars containing either straw (HS) or woodchip (HW) bedding were pyrolyzed at 700°C and characterized for their physical and chemical properties. Tests revealed both biochars had high alkalinity, moderate specific conductivity, and low surface area as compared to other biochars in the literature. HS contained more mineral structures than HW. Scanning electron microscopy presented differences in particle shape, size, and presence …
Catechol Oxidation By Ozone And Hydroxyl Radicals At The Air-Water Interface, Elizabeth A. Pillar, Robert C. Camm, Marcelo I. Guzman
Catechol Oxidation By Ozone And Hydroxyl Radicals At The Air-Water Interface, Elizabeth A. Pillar, Robert C. Camm, Marcelo I. Guzman
Chemistry Faculty Publications
Anthropogenic emissions of aromatic hydrocarbons promptly react with hydroxyl radicals undergoing oxidation to form phenols and polyphenols (e.g., catechol) typically identified in the complex mixture of humic-like substances (HULIS). Because further processing of polyphenols in secondary organic aerosols (SOA) can continue mediated by a mechanism of ozonolysis at interfaces, a better understanding about how these reactions proceed at the air–water interface is needed. This work shows how catechol, a molecular probe of the oxygenated aromatic hydrocarbons present in SOA, can contribute interfacial reactive species that enhance the production of HULIS under atmospheric conditions. Reactive semiquinone radicals are quickly produced upon …
Interactive Comment On “Iodine Oxide In The Global Marine Boundary Layer” By C. Prados-Roman Et Al., Marcelo I. Guzman
Interactive Comment On “Iodine Oxide In The Global Marine Boundary Layer” By C. Prados-Roman Et Al., Marcelo I. Guzman
Chemistry Faculty Publications
No abstract provided.
Racial Disparities In Access To Community Water Supply Service In Wake County, North Carolina, Jacqueline Macdonald Gibson, Nicholas Defelice, Daniel Sebastian, Hannah Leker
Racial Disparities In Access To Community Water Supply Service In Wake County, North Carolina, Jacqueline Macdonald Gibson, Nicholas Defelice, Daniel Sebastian, Hannah Leker
Frontiers in Public Health Services and Systems Research
Anecdotal evidence suggests that historically African American communities on the fringes of cities and towns in North Carolina have been systematically denied access to municipal drinking water service. This paper presents the first statistical analysis of the role of race in determining water access in these fringe areas, known as extraterritorial jurisdictions. Using publicly available property tax data, we quantified the percentage of residences with municipal water service in each census block in Wake County (the second-largest by population in North Carolina). Using the resulting water service maps plus 2010 U.S. Census data, we employed a logistic regression to assess …
Synthesis And Characterization Of High-Iron Alite-Calcium Sulfoaluminate-Ferrite Cements Produced From Industrial By-Products, Tristana Y. Duvallet, Youngmin Zhou, Thomas L. Robl, Rodney Andrews
Synthesis And Characterization Of High-Iron Alite-Calcium Sulfoaluminate-Ferrite Cements Produced From Industrial By-Products, Tristana Y. Duvallet, Youngmin Zhou, Thomas L. Robl, Rodney Andrews
Coal Combustion and Gasification Products Journal Archive
Ordinary Portland cement (OPC) and calcium sulfoaluminate cement (CSAC) are well-known and commonly used construction materials. The clinker phases mainly responsible for their strength development are C3S (alite) in OPC, which hydrates to form a calcium silicate gel phase; and C4A3S ´ (calcium sulfoaluminate) in CSAC, which hydrates to rapidly form ettringite. The purpose of this work was to produce high-iron alite-calcium sulfoaluminate-ferrite cements, by combining C4AF (ferrite), from 5% to 50% by weight, to the C3S and C4A3S ´ clinker phases. Producing this alite-calcium sulfoaluminate-ferrite cement would decrease the requirement of bauxite in the raw materials, which would consequently …
Experimental And Modelling Evaluation Of Slagging Behaviour Of German Lignite, Martin Kaiser, Alexander Ilyushechkin
Experimental And Modelling Evaluation Of Slagging Behaviour Of German Lignite, Martin Kaiser, Alexander Ilyushechkin
Coal Combustion and Gasification Products Journal Archive
The behaviour of mineral matter is important for the characterisation of coal for use in entrained-flow gasification technologies. We investigated four behavioural characteristics—ash fusion temperatures (AFT), slag viscosity versus temperature profiles, temperatures of critical viscosity (TCV), and slag phase compositions—of Rhenish lignite coal ash using laboratory and modelling tools. Our modelling of AFT using coal ash composition provided a wide range of data, with only one (modified) model demonstrating agreement with experimental data. Experimental slag viscosity data were obtained over a temperature range from 1200uC to 1500uC. Where relevant, TCV was also measured. Comparison of these data to the calculated …
Fly Ash As A Potential Scrubber Of Acidic Wastes From The Phosphate Industries In Israel, Roy Nir Lieberman, Eli Lederman, Ithamar Pelly, Haim Cohen
Fly Ash As A Potential Scrubber Of Acidic Wastes From The Phosphate Industries In Israel, Roy Nir Lieberman, Eli Lederman, Ithamar Pelly, Haim Cohen
Coal Combustion and Gasification Products Journal Archive
Fly ash (FA) is produced in Israeli utilities via bituminous coal combustion. It is used as a cement additive or in concrete production, and its economic value is low. The FA produced in Israel is very basic (defined as class F) owing to ambient air quality standards that impose low sulfur content in the imported coals. Because the lime content is high (in the South African coal, ,10 wt%), it is a good potential chemical scrubber to acidic wastes. The phosphate industry in Israel produces mainly phosphate fertilizers and water-treatment products as well as phosphoric acid. The production methods rely …
Geochemistry And Mineralogy Of Coal-Fired Circulating Fluidized Bed Combustion Fly Ashes, Luis F.O. Silva, Marcos L.S. Oliveira, Rubens M. Kautzmann, Claudete G. Ramos, Maria Izquierdo, Shifeng Dai, Jennifer Wilcox, Jeremy Hoffman, James C. Hower
Geochemistry And Mineralogy Of Coal-Fired Circulating Fluidized Bed Combustion Fly Ashes, Luis F.O. Silva, Marcos L.S. Oliveira, Rubens M. Kautzmann, Claudete G. Ramos, Maria Izquierdo, Shifeng Dai, Jennifer Wilcox, Jeremy Hoffman, James C. Hower
Coal Combustion and Gasification Products Journal Archive
The fuel, bed ash, and fly ash were sampled from a circulating fluidized bed combustion (CFBC) unit at two times. The first sampling was a high-sulfur (S) coal-only run, and the second sampling coincided with an experimental burn of up to 10% switchgrass (Panicum virgatum) pressed pellets mixed with a high-S coal. The latter blend had a higher moisture content and a lower heating value than the coal-only fuel. Given the time between the samplings and the special needs for the experimental run, unavoidable changes in the coal and limestone complicate comparisons of the bed ash and fly ash chemistry …
Trends In Coal Utilization And Coal Combustion Product Production In Kentucky: Results Of The 2012 Survey Of Power Plants, James C. Hower, Gerald A. Thomas, Shelley G. Hopps
Trends In Coal Utilization And Coal Combustion Product Production In Kentucky: Results Of The 2012 Survey Of Power Plants, James C. Hower, Gerald A. Thomas, Shelley G. Hopps
Coal Combustion and Gasification Products Journal Archive
The University of Kentucky Center for Applied Energy Research has conducted a survey of Kentucky’s utility coal-fired power plants every 5 years since 1992. The survey includes a collection of the feed coal and the coal combustion products (CCPs). The latest collection was in 2012, with the accompanying information survey covering trends in 2011. Overall coal-fired energy production decreased, and the nature of the CCPs changed for a number of reasons, including but not limited to, increased gas production in the Appalachians, a series of warm winters, energy conservation, depletion of Appalachian coal reserves, and utility responses to regulations. From …
Decelerating Open Channel Flow Over Gravel: Turbulence Structure & Sensor Development, Robert L. Stewart Iii
Decelerating Open Channel Flow Over Gravel: Turbulence Structure & Sensor Development, Robert L. Stewart Iii
Theses and Dissertations--Civil Engineering
This dissertation describes investigations of fully turbulent decelerating hydraulically roughbed flow over gravel and the development of technology to measure turbulence and associated sediment transport in streams. Theory is developed for predicting velocity distributions in simple uniform flow using the asymptotic invariance principle and tested using laboratory and field collected data. A mixed scale is developed that accounts for bed derived turbulent structures throughout the flows depth and is used to parameterize the external boundary’s effect on the flow for the logarithmic and outer layers. The asymptotic invariance principle and similarity analysis is conducted for the equations of motion in …
The John Zink Hamworthy Combustion Handbook, 2nd Edition, Volume 1: Fundamentals, Edited By Charles E. Baukal, Jr., Crc Press, Boca Raton, Fl, 2013., Payal A. Chandan
The John Zink Hamworthy Combustion Handbook, 2nd Edition, Volume 1: Fundamentals, Edited By Charles E. Baukal, Jr., Crc Press, Boca Raton, Fl, 2013., Payal A. Chandan
Coal Combustion and Gasification Products Journal Archive
No abstract provided.
Location Of Cerium In Coal-Combustion Fly Ashes: Implications For Recovery Of Lanthanides, James C. Hower, John G. Groppo, Prakash Joshi, Shifeng Dai, David P. Moecher, Michelle N. Johnston
Location Of Cerium In Coal-Combustion Fly Ashes: Implications For Recovery Of Lanthanides, James C. Hower, John G. Groppo, Prakash Joshi, Shifeng Dai, David P. Moecher, Michelle N. Johnston
Coal Combustion and Gasification Products Journal Archive
Given the worldwide demand for rare earth elements (REEs) in modern electronics, all potential sources of the REEs should be investigated. Coal-combustion fly ash represents a potential source of REEs. Fly ashes, derived from the combustion of coals from Kentucky in the United States and Jungar in China, were examined by wavelength-dispersive spectrometry electron microprobe analysis of epoxy-bound polished pellets. From previous studies, it was known that the REEs did not show any enrichment relative to flue gas temperature at the point of collection or to the particle size, that is, external surface area, of the particles. Cerium, the most …
Chemical Partitioning And Mobility Of Trace Elements In Dry Disposed Weathered Ash Conditioned With High-Saline Effluents, S.A. Akinyemi, A. Akinlua, W.M. Gitari, R.O. Akinyeye, L.F. Petrik
Chemical Partitioning And Mobility Of Trace Elements In Dry Disposed Weathered Ash Conditioned With High-Saline Effluents, S.A. Akinyemi, A. Akinlua, W.M. Gitari, R.O. Akinyeye, L.F. Petrik
Coal Combustion and Gasification Products Journal Archive
Weinvestigated the mobility of inorganic elements in the ash dump due to chemical interaction of weathered dry disposed ash conditioned with high-saline effluents and ingressed CO2 from atmosphere and percolating rainwater. Drilled ash core samples collected from dry disposed ash dump at a South African coal-burning power station were characterized using X-ray diffraction (XRD) and X-ray fluorescence (XRF) analyses. A modified sequential extraction procedure was selected to determine the mineralogical association of the investigated elements in the 1-year-old drilled ash cores. Major mineral phases are quartz and mullite and other minor phases included hematite, lime, calcite, anorthite, mica, and enstatite. …
Effects Of Coal Combustion By-Product–Encapsulated Ammonium Nitrate On Wheat Yield And Uptake Of Nitrogen And Metals, Eton E. Codling
Effects Of Coal Combustion By-Product–Encapsulated Ammonium Nitrate On Wheat Yield And Uptake Of Nitrogen And Metals, Eton E. Codling
Coal Combustion and Gasification Products Journal Archive
Ammonium nitrate (AN) is an essential plant nutrient for plant growth. Ammonium nitrate is also an ingredient in explosives. Research is being conducted on reducing the explosiveness of AN by encapsulating it with the use of coal by-products. The objective of this greenhouse pot study was to determine the effects of class C and F fly ash and flue gas desulfurization-gypsum-encapsulated AN on biomass, grain, and straw yield and nitrogen and metals uptake by wheat. Encapsulated AN was mixed with a low-nitrogen soil at 56 and 112 kg N ha^-1^, as well as unencapsulated AN as a control, and planted …
Geotechnical Characterization Of Clinker-Stabilized Fly Ash–Coal Mine Overburden Mixes For Subbase Of Mine Haul Road, Soumya Ranjan Mallick, Manoj Kumar Mishra
Geotechnical Characterization Of Clinker-Stabilized Fly Ash–Coal Mine Overburden Mixes For Subbase Of Mine Haul Road, Soumya Ranjan Mallick, Manoj Kumar Mishra
Coal Combustion and Gasification Products Journal Archive
Fly ash is a major by-product of thermal power plants that adversely affects land, water, and air. Its gainful utilization in many areas is being continuously explored. Use of fly ash in opencast coal mine haul road construction is one such option. This article reports detailed laboratory investigations carried out on clinker-stabilized fly ash–mine overburden mixes to evaluate their suitability for subbase of mine haul roads. Composite materials were prepared from fly ash, mine overburden, and clinker at different proportions. Proctor compaction test, unconfined compressive strength (UCS), and ultrasonic pulse velocity tests were carried out at different curing periods. UCS …
A Note On The Occurrence Of Yttrium And Rare Earth Elements In Coal Combustion Products, James C. Hower, Shifeng Dai, Vladimir V. Seredin, Lei Zhao, Irena J. Kostova, Luis F.O. Silva, Sarah M. Mardon, Gulbin Gurdal
A Note On The Occurrence Of Yttrium And Rare Earth Elements In Coal Combustion Products, James C. Hower, Shifeng Dai, Vladimir V. Seredin, Lei Zhao, Irena J. Kostova, Luis F.O. Silva, Sarah M. Mardon, Gulbin Gurdal
Coal Combustion and Gasification Products Journal Archive
There is an international need for a variety of lanthanide elements (rare earth elements, or REEs) in modern electronic and related components. This has led to a desire to broaden production from both previously productive locations and to expand production to new sources, possibly including coal-derived fly ash. The concentration of lanthanides in coal-combustion fly ash depends on a number of factors, one of the most important being the concentration of the elements in the feed coal. Unlike some elements, such as Zn and As, the REE concentration is largely not a function of element volatility. In this study, we …