The Experts below are selected from a list of 57 Experts worldwide ranked by ideXlab platform
James C. Hower - One of the best experts on this subject based on the ideXlab platform.
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impact of coal source changes on mercury content in Fly Ash examples from a kentucky power plant
International Journal of Coal Geology, 2017Co-Authors: James C. Hower, Herek L Clack, Madison M Hood, Shelley Hopps, Gerald H ThomasAbstract:Abstract Mercury capture by coal combustion Fly Ash is a function of the chemistry of the feed coal, including halogens; the amount and type of Carbon in the Fly Ash; and the type of Fly Ash collection and the flue gas temperature at the point of Fly Ash collection. In this study of Fly Ash collected at different points in time from a five-row electrostatic precipitator (ESP) system at a Kentucky power plant, relationships were seen between the amount of Fly Ash Carbon and the concentration of Hg in the Ash. Coincident with the burning of low-S coal at two collection times, a better correlation between Hg and C was seen in the relatively cooler 3rd and 4th ESP rows than in the first two rows. This was particularly evident in the 2007 collection where the Fly Ash Carbon was higher than in the 2004 collection. In 2013, following the installation of flue-gas desulfurization and the resulting switch to high-S coal and the installation of a hydrated-lime injection system between the 2nd and 3rd ESP rows, no significant Hg vs. C trend was observed.
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The occurrence of hazardous volatile elements and nanoparticles in Bulgarian coal Fly Ashes and the effect on human health exposure.
The Science of the total environment, 2011Co-Authors: Luis F.o. Silva, Kátia Daboit, Carlos Hoffmann Sampaio, André Jasper, María Luisa Andrade, Irena Kostova, Frans Waanders, Kevin R. Henke, James C. HowerAbstract:Low-rank, high-mineral matter Bulgarian coals were studied using a variety of chemical, optical, and electron beam methods. The larger Fly Ash Carbon phases include charred Carbons in contrast to coked Carbons present in the Fly Ashes of bituminous-coal-derived Fly Ashes. Nanoscale Carbons include multi-walled Carbon nanotubes (MWCNTs) encapsulating Hg, Se, and As, among other elements. In addition to the glass which dominates the Fly Ash, relatively coarse 'rock fragments', consisting of an unmelted to partially melted core surrounded by a glassy rim, are present in the Fly Ash. Nano-scale minerals can contain hazardous elements and, along with metal-bearing multiwalled nanotubes, can be a path for the entry of hazardous particles into the lungs and other organs.
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mercury capture by selected bulgarian Fly Ashes influence of coal rank and Fly Ash Carbon pore structure on capture efficiency
Applied Geochemistry, 2011Co-Authors: Irena Kostova, James C. Hower, Maria Mastalerz, Stanislav V VassilevAbstract:Mercury capture by Fly Ash C was investigated at five lignite- and subbituminous-coal-burning Bulgarian power plants (Republika, Bobov Dol, Maritza East 2, Maritza East 3, and Sliven). Although the C content of the Ashes is low, never exceeding 1.6%, the Hg capture on a unit C basis demonstrates that the low-rank-coal-derived Fly Ash Carbons are more efficient in capturing Hg than Fly Ash Carbons from bituminous-fired power plants. While some low-C and low-Hg Fly Ashes do not reveal any trends of Hg versus C, the 2nd and, in particular, the 3rd electrostatic precipitator (ESP) rows at the Republika power plant do have sufficient Fly Ash C range and experience flue gas sufficiently cool to capture measurable amounts of Hg. The Republika 3rd ESP row exhibits an increase in Hg with increasing C, as observed in other power plants, for example, in Kentucky power plants burning Appalachian-sourced bituminous coals. Mercury/C decreases with an increase in Fly Ash C, suggesting that some of the C is isolated from the flue gas stream and does not contribute to Hg capture. Mercury capture increases with an increase in Brunauer–Emmett–Teller (BET) surface area and micropore surface area. The differences in Hg capture between the Bulgarian plants burning low-rank coal and high volatile bituminous-fed Kentucky power plants suggests that the variations in C forms resulting from the combustion of the different ranks also influence the efficiency of Hg capture.
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characteristics of coal combustion products ccp s from kentucky power plants with emphasis on mercury content
Fuel, 2005Co-Authors: James C. Hower, Tanaporn Sakulpitakphon, Thomas L Robl, C Anderson, Gerald A Thomas, Sarah M Mardon, W L ClarkAbstract:Abstract The Center for Applied Energy Research conducts a survey of Kentucky's coal-fired power plants every five years. The last survey was conducted in 2002 and covered most units at all of the plants in Kentucky. Special emphasis was placed on the spatial distribution of Ash products, with each row of ESP's or baghouses samples wherever possible. In this manner, we can track the change in concentration of trace elements with relative temperature of the flue gas. Certain elements, such as Zn, Pb, and As, are known to be temperature dependent. The behavior of Hg, while also temperature dependent, is more complex owing to the adsorption of Hg on Fly Ash Carbon. The survey provides a wide array of coal sources, ESP/baghouse collection temperatures, and Fly Ash Carbon composition, all important in determining the behavior of Hg in the flue gas. In addition, many plants have FGD systems, allowing an assessment of the efficiency of FGD in capturing Hg from the post-ESP flue gas.
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Mercury capture by distinct Fly Ash Carbon forms
Energy & Fuels, 2000Co-Authors: James C. Hower, M. Mercedes Maroto-valer, Darrell N. Taulbee, Tanaporn SakulpitakphonAbstract:Carbon was separated from the Fly Ash from a Kentucky power plant using density gradient centrifugation and a lithium heterolpolytungstate high-density media. Relative concentrations of inertinite (up to 77% vol), isotropic Carbon (up to 77% vol), and anisotropic Carbon (up to 76% vol) were isolated from the original Fly Ash. Mercury concentration was lowest in the parent Fly Ash (which contains non-Carbon components); followed by inertinite, isotropic coke, mixed isotropic−anisotropic coke fraction, and, with the highest concentration, the anisotropic coke concentrate. The latter order corresponds to the increase in BET surface area of the Fly Ash Carbons. Previous studies have demonstrated the capture of mercury by Fly Ash Carbon. This study confirms prior work demonstrating the varying role of Carbon types in the capture, implying that variability in the Carbon forms influences the amount of mercury retained on the Fly Ash.
Tanaporn Sakulpitakphon - One of the best experts on this subject based on the ideXlab platform.
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characteristics of coal combustion products ccp s from kentucky power plants with emphasis on mercury content
Fuel, 2005Co-Authors: James C. Hower, Tanaporn Sakulpitakphon, Thomas L Robl, C Anderson, Gerald A Thomas, Sarah M Mardon, W L ClarkAbstract:Abstract The Center for Applied Energy Research conducts a survey of Kentucky's coal-fired power plants every five years. The last survey was conducted in 2002 and covered most units at all of the plants in Kentucky. Special emphasis was placed on the spatial distribution of Ash products, with each row of ESP's or baghouses samples wherever possible. In this manner, we can track the change in concentration of trace elements with relative temperature of the flue gas. Certain elements, such as Zn, Pb, and As, are known to be temperature dependent. The behavior of Hg, while also temperature dependent, is more complex owing to the adsorption of Hg on Fly Ash Carbon. The survey provides a wide array of coal sources, ESP/baghouse collection temperatures, and Fly Ash Carbon composition, all important in determining the behavior of Hg in the flue gas. In addition, many plants have FGD systems, allowing an assessment of the efficiency of FGD in capturing Hg from the post-ESP flue gas.
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Mercury capture by distinct Fly Ash Carbon forms
Energy & Fuels, 2000Co-Authors: James C. Hower, M. Mercedes Maroto-valer, Darrell N. Taulbee, Tanaporn SakulpitakphonAbstract:Carbon was separated from the Fly Ash from a Kentucky power plant using density gradient centrifugation and a lithium heterolpolytungstate high-density media. Relative concentrations of inertinite (up to 77% vol), isotropic Carbon (up to 77% vol), and anisotropic Carbon (up to 76% vol) were isolated from the original Fly Ash. Mercury concentration was lowest in the parent Fly Ash (which contains non-Carbon components); followed by inertinite, isotropic coke, mixed isotropic−anisotropic coke fraction, and, with the highest concentration, the anisotropic coke concentrate. The latter order corresponds to the increase in BET surface area of the Fly Ash Carbons. Previous studies have demonstrated the capture of mercury by Fly Ash Carbon. This study confirms prior work demonstrating the varying role of Carbon types in the capture, implying that variability in the Carbon forms influences the amount of mercury retained on the Fly Ash.
Kenneth Ladwig - One of the best experts on this subject based on the ideXlab platform.
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laboratory study of air water coal combustion product Fly Ash and fgd solid mercury exchange
Fuel, 2006Co-Authors: Mei Xin, Mae Sexauer Gustin, Kenneth LadwigAbstract:Recent laboratory research has indicated that coal Fly Ash derived from subbituminous and bituminous type coals is a sink for atmospheric mercury (Hg), however lignite-based Ash was found to emit Hg to the air. Solids collected from systems with components that enhance Hg removal (i.e. activated Carbon injection (ACI), flue gas desulfurization (FGD), and selective catalytic reduction (SCR) or selective non-catalytic reduction (SNCR)) may have higher Hg concentrations and therefore a higher potential for Hg release. For this study we investigated the potential for Hg release to the air and water from coal combustion products (CCPs) collected from coal-fired units with FGD equipment, SCR and SNCR equipment, and sorbent injection for Hg removal. In the laboratory study, most dry samples acted as sinks for atmospheric Hg in the dark at 25 °C. When exposed to light or increased temperature (45 °C), deposition of Hg to the Fly Ash substrates in most cases continued but decreased. Wet FGD samples emitted Hg. However, they became a sink for atmospheric Hg or exhibited low Hg emission rates when dried. Mercury flux in the dark at 25 °C was correlated with Fly Ash Carbon content (LOI). Most liquid extracts derived using the synthetic precipitation leaching procedure (SPLP EPA method 1312) had very low Hg concentrations (<13 ng/l).
Stanislav V Vassilev - One of the best experts on this subject based on the ideXlab platform.
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mercury capture by selected bulgarian Fly Ashes influence of coal rank and Fly Ash Carbon pore structure on capture efficiency
Applied Geochemistry, 2011Co-Authors: Irena Kostova, James C. Hower, Maria Mastalerz, Stanislav V VassilevAbstract:Mercury capture by Fly Ash C was investigated at five lignite- and subbituminous-coal-burning Bulgarian power plants (Republika, Bobov Dol, Maritza East 2, Maritza East 3, and Sliven). Although the C content of the Ashes is low, never exceeding 1.6%, the Hg capture on a unit C basis demonstrates that the low-rank-coal-derived Fly Ash Carbons are more efficient in capturing Hg than Fly Ash Carbons from bituminous-fired power plants. While some low-C and low-Hg Fly Ashes do not reveal any trends of Hg versus C, the 2nd and, in particular, the 3rd electrostatic precipitator (ESP) rows at the Republika power plant do have sufficient Fly Ash C range and experience flue gas sufficiently cool to capture measurable amounts of Hg. The Republika 3rd ESP row exhibits an increase in Hg with increasing C, as observed in other power plants, for example, in Kentucky power plants burning Appalachian-sourced bituminous coals. Mercury/C decreases with an increase in Fly Ash C, suggesting that some of the C is isolated from the flue gas stream and does not contribute to Hg capture. Mercury capture increases with an increase in Brunauer–Emmett–Teller (BET) surface area and micropore surface area. The differences in Hg capture between the Bulgarian plants burning low-rank coal and high volatile bituminous-fed Kentucky power plants suggests that the variations in C forms resulting from the combustion of the different ranks also influence the efficiency of Hg capture.
Irena Kostova - One of the best experts on this subject based on the ideXlab platform.
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The occurrence of hazardous volatile elements and nanoparticles in Bulgarian coal Fly Ashes and the effect on human health exposure.
The Science of the total environment, 2011Co-Authors: Luis F.o. Silva, Kátia Daboit, Carlos Hoffmann Sampaio, André Jasper, María Luisa Andrade, Irena Kostova, Frans Waanders, Kevin R. Henke, James C. HowerAbstract:Low-rank, high-mineral matter Bulgarian coals were studied using a variety of chemical, optical, and electron beam methods. The larger Fly Ash Carbon phases include charred Carbons in contrast to coked Carbons present in the Fly Ashes of bituminous-coal-derived Fly Ashes. Nanoscale Carbons include multi-walled Carbon nanotubes (MWCNTs) encapsulating Hg, Se, and As, among other elements. In addition to the glass which dominates the Fly Ash, relatively coarse 'rock fragments', consisting of an unmelted to partially melted core surrounded by a glassy rim, are present in the Fly Ash. Nano-scale minerals can contain hazardous elements and, along with metal-bearing multiwalled nanotubes, can be a path for the entry of hazardous particles into the lungs and other organs.
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mercury capture by selected bulgarian Fly Ashes influence of coal rank and Fly Ash Carbon pore structure on capture efficiency
Applied Geochemistry, 2011Co-Authors: Irena Kostova, James C. Hower, Maria Mastalerz, Stanislav V VassilevAbstract:Mercury capture by Fly Ash C was investigated at five lignite- and subbituminous-coal-burning Bulgarian power plants (Republika, Bobov Dol, Maritza East 2, Maritza East 3, and Sliven). Although the C content of the Ashes is low, never exceeding 1.6%, the Hg capture on a unit C basis demonstrates that the low-rank-coal-derived Fly Ash Carbons are more efficient in capturing Hg than Fly Ash Carbons from bituminous-fired power plants. While some low-C and low-Hg Fly Ashes do not reveal any trends of Hg versus C, the 2nd and, in particular, the 3rd electrostatic precipitator (ESP) rows at the Republika power plant do have sufficient Fly Ash C range and experience flue gas sufficiently cool to capture measurable amounts of Hg. The Republika 3rd ESP row exhibits an increase in Hg with increasing C, as observed in other power plants, for example, in Kentucky power plants burning Appalachian-sourced bituminous coals. Mercury/C decreases with an increase in Fly Ash C, suggesting that some of the C is isolated from the flue gas stream and does not contribute to Hg capture. Mercury capture increases with an increase in Brunauer–Emmett–Teller (BET) surface area and micropore surface area. The differences in Hg capture between the Bulgarian plants burning low-rank coal and high volatile bituminous-fed Kentucky power plants suggests that the variations in C forms resulting from the combustion of the different ranks also influence the efficiency of Hg capture.