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Author: Xiaofei Wang Publisher: ISBN: Category : Electronic dissertations Languages : en Pages : 260
Book Description
Pulverized coal combustion is widely used worldwide for the production of electricity. However, it is one of the primary emission sources of air pollutants, including particulate matter (fly ash) and mercury (Hg), into the atmosphere. This dissertation investigated three aspects of pollutant formation and control from the coal combustion process: (1) organic aerosol formation during coal combustion, (2) mercury removal during coal combustion by injection of Vanadium Pentoxide (V2O5), and (3) submicrometer particle formation during oxy-coal combustion. Part. 1. While the characterization and formation of the mineral matter component of aerosol during coal combustion has been well studied and understood, the characterization and fate of corresponding organic matter content was not examined in detail earlier. The first part of this dissertation studies the formation mechanism of organic aerosols during coal combustion. Pilot-scale experiments were conducted in a 1 MW coal combustor, and showed that black carbon aerosol formation was greatly enhanced by increasing the fuel-air equivalence ratio. However, organic carbon aerosol formation was lowered by increasing the fuel-air equivalence ratio, which was opposite to the trend of black carbon aerosol formation. This phenomenon indicates that the formation mechanism of organic carbon aerosol is different from black carbon (soot) aerosol. Detailed organic aerosol formation mechanisms have been studied in a laboratory-scale system. Aerosol mass spectrometry techniques were applied to characterize both coal combustion aerosols from a drop-tube coal combustor and coal pyrolysis products from a flat-flame coal pyrolyzer. The chemical composition of major species for both combustion organic aerosols and pyrolysis products are hydrocarbons, carboxylic acids and aromatic compounds. The similarities of the chemical compositions demonstrate that the products from coal pyrolysis, (the initial step of coal combustion), are the precursors of organic aerosols. More carboxylic acids and oxygenated organic compounds were found in the combustion aerosols, indicating that many pyrolysis products are oxidized before they are converting to organic aerosols. A strong correlation between inorganic and organic aerosol formation mechanisms has been found in this work, demonstrating that inorganic particles play a critical role as carriers of organic species. Sulfate species in inorganic aerosols play a particularly important role in organic aerosol formation. Enhanced organic aerosol formation during the combustion of high sulfur content coal has been observed for the first time. High resolution mass spectra analysis shows the presence of amine-like organics in the aerosols. The correlation between particulate sulfate and organics suggests that acidic sulfate particles may absorb basic amine-like organics, a major coal pyrolysis product, from the gas phase into the particle phase via acid-base neutralization reactions. Part. 2. Coal combustion is a major source of atmospheric mercury. High-temperature sorbent injection is an efficient method to capture metallic species during combustion. This part of the study examines the performance on Hg capture from pulverized coal combustion in a drop-tube furnace. V2O5 was tested as a sorbent and demonstrated good performance on elemental mercury capture, which results from the formation of ultrafine V2O5 particles during the combustion process. It is proposed that the ultrafine V2O5 particles catalyzed Hg0 oxidation on their large surfaces. Hg2+, the oxidation product, may condense on fly ash particle surfaces or on tubing surfaces, thereby being removed from the flue gas. Part. 3. Coal combustion is the largest single contributor to global anthropogenic CO2 emissions. Oxy-coal combustion replaces the air with oxygen and uses recycled flue gas (RFG) as a diluent, resulting in a higher concentration (>98%) of CO2 in the exhaust, which promotes more effective control, capture, and possible conversion of CO2. This part of the dissertation investigates the effects of recycling (up to recycle ratios of 60%) on submicrometer particle formation in a drop-tube furnace system. The recycled exhaust gas containing lower O2 concentration and higher CO2 concentration suppressed submicrometer particle formation. However, it was found that water vapor in recycled exhaust gas greatly enhanced the formation of submicrometer particles. The gas composition changes that result from exhaust-gas recycling significantly affected the size distribution of submicrometer particles at the exit of the combustor. Differences in the particle size distribution with and without the filtration of recycled exhaust gas were insignificant. The composition of the resultant particles in oxy-coal combustion and conventional coal-air combustion as determined by X-ray diffraction was similar.
Author: Xiaofei Wang Publisher: ISBN: Category : Electronic dissertations Languages : en Pages : 260
Book Description
Pulverized coal combustion is widely used worldwide for the production of electricity. However, it is one of the primary emission sources of air pollutants, including particulate matter (fly ash) and mercury (Hg), into the atmosphere. This dissertation investigated three aspects of pollutant formation and control from the coal combustion process: (1) organic aerosol formation during coal combustion, (2) mercury removal during coal combustion by injection of Vanadium Pentoxide (V2O5), and (3) submicrometer particle formation during oxy-coal combustion. Part. 1. While the characterization and formation of the mineral matter component of aerosol during coal combustion has been well studied and understood, the characterization and fate of corresponding organic matter content was not examined in detail earlier. The first part of this dissertation studies the formation mechanism of organic aerosols during coal combustion. Pilot-scale experiments were conducted in a 1 MW coal combustor, and showed that black carbon aerosol formation was greatly enhanced by increasing the fuel-air equivalence ratio. However, organic carbon aerosol formation was lowered by increasing the fuel-air equivalence ratio, which was opposite to the trend of black carbon aerosol formation. This phenomenon indicates that the formation mechanism of organic carbon aerosol is different from black carbon (soot) aerosol. Detailed organic aerosol formation mechanisms have been studied in a laboratory-scale system. Aerosol mass spectrometry techniques were applied to characterize both coal combustion aerosols from a drop-tube coal combustor and coal pyrolysis products from a flat-flame coal pyrolyzer. The chemical composition of major species for both combustion organic aerosols and pyrolysis products are hydrocarbons, carboxylic acids and aromatic compounds. The similarities of the chemical compositions demonstrate that the products from coal pyrolysis, (the initial step of coal combustion), are the precursors of organic aerosols. More carboxylic acids and oxygenated organic compounds were found in the combustion aerosols, indicating that many pyrolysis products are oxidized before they are converting to organic aerosols. A strong correlation between inorganic and organic aerosol formation mechanisms has been found in this work, demonstrating that inorganic particles play a critical role as carriers of organic species. Sulfate species in inorganic aerosols play a particularly important role in organic aerosol formation. Enhanced organic aerosol formation during the combustion of high sulfur content coal has been observed for the first time. High resolution mass spectra analysis shows the presence of amine-like organics in the aerosols. The correlation between particulate sulfate and organics suggests that acidic sulfate particles may absorb basic amine-like organics, a major coal pyrolysis product, from the gas phase into the particle phase via acid-base neutralization reactions. Part. 2. Coal combustion is a major source of atmospheric mercury. High-temperature sorbent injection is an efficient method to capture metallic species during combustion. This part of the study examines the performance on Hg capture from pulverized coal combustion in a drop-tube furnace. V2O5 was tested as a sorbent and demonstrated good performance on elemental mercury capture, which results from the formation of ultrafine V2O5 particles during the combustion process. It is proposed that the ultrafine V2O5 particles catalyzed Hg0 oxidation on their large surfaces. Hg2+, the oxidation product, may condense on fly ash particle surfaces or on tubing surfaces, thereby being removed from the flue gas. Part. 3. Coal combustion is the largest single contributor to global anthropogenic CO2 emissions. Oxy-coal combustion replaces the air with oxygen and uses recycled flue gas (RFG) as a diluent, resulting in a higher concentration (>98%) of CO2 in the exhaust, which promotes more effective control, capture, and possible conversion of CO2. This part of the dissertation investigates the effects of recycling (up to recycle ratios of 60%) on submicrometer particle formation in a drop-tube furnace system. The recycled exhaust gas containing lower O2 concentration and higher CO2 concentration suppressed submicrometer particle formation. However, it was found that water vapor in recycled exhaust gas greatly enhanced the formation of submicrometer particles. The gas composition changes that result from exhaust-gas recycling significantly affected the size distribution of submicrometer particles at the exit of the combustor. Differences in the particle size distribution with and without the filtration of recycled exhaust gas were insignificant. The composition of the resultant particles in oxy-coal combustion and conventional coal-air combustion as determined by X-ray diffraction was similar.
Author: Achariya Suriyawong Publisher: ISBN: Category : Electronic dissertations Languages : en Pages : 266
Book Description
Energy is the issue of great importance at the present. Coal, the cheapest and the most abundant reserve fossil fuel, is currently one of the most widely used energy source globally and will continue to be in the foreseeable future. The use of coal has also posed many world-wide environmental challenges, including the control of particulate matter, mercury, and trace metals, and carbon oxide (CO2) emissions. The rising of CO2 level in the atmosphere due to burning of fossil fuels is one of the major factors contributing to the global climate change. Capturing CO2 from coal combustion exhaust has been receiving significant attention; however, the volume fraction of CO2 in conventional coal combustion system (with air) ranges only 13%-15%, making it difficult to cost-effectively design the systems. Oxy-coal combustion or O2/CO2 recycled coal combustion is one of the promising techniques to overcome the limitation of low CO2 concentration in the exhaust. Before this technology can be employed, the effects of oxy-coal combustion on the pollutants associated with coal combustion, including fine particle, gaseous mercury and heavy metal emissions, need to be established. In addition, the influences of oxy-coal combustion on the performance of the current pollution control technologies, such as an electrostatic precipitator (ESP), need to be addressed. This dissertation investigated two aspects of coal combustion process: (1) pollutant formation, specifically submicrometer particles and mercury, and (2) pollutant control. The first part of dissertation addresses the impact of oxy-coal combustion on the formation submicrometer particles and the speciation of gaseous mercury. The second part focuses on the performance of two pollutant control technologies, including an ESP for capturing submicrometer particles and nano-structured TiO2 with UV irradiation for mercury capture. The findings presented here can be broadly divided into three parts. The first part reports the influence of oxy-coal combustion on submicrometer particle formation and capture using an ESP. The second part addresses the impacts of oxy-coal combustion on mercury speciation. The third part investigates the performance of nano-structured sorbent for capturing mercury and controlling heavy metal emissions from combustion process. The findings presented here can be used as a guideline for proper operation and control of pollutants generated from both oxy-coal and conventional combustion systems.
Author: Publisher: ISBN: Category : Languages : en Pages :
Book Description
The objectives for this reporting period are: 1) The study of mercury capture mechanism by using titania sorbent and ultraviolet (UV) light, and the study of structural difference between titania particle generated by both thermal Oxidation at 1000EC and by reacting with water vapor at room temperature. 2) Measurement of ultra-fine particle size distribution in flue gas after burning coal.
Author: Erdem Sasmaz Publisher: Stanford University ISBN: Category : Languages : en Pages : 195
Book Description
Coal-fired power plants are a major anthropogenic source of worldwide mercury (Hg) emissions. Since mercury is considered to be one of the most toxic metals found in the environment, Hg emissions from coal-fired power plants is of major environmental concern. Mercury in coal is vaporized into its gaseous elemental form throughout the coal combustion process. Elemental Hg can be oxidized in subsequent reactions with other gaseous components (homogeneous) and solid materials (heterogeneous) in coal-fired flue gases. While oxidized Hg in coal-fired flue gases is readily controlled by its adsorption onto fly ash and/or its dissolution into existing solution-based sulfur dioxide (SO2) scrubbers, elemental Hg is not controlled. The extent of elemental Hg formed during coal combustion is difficult to predict since it is dependent on the type of coal burned, combustion conditions, and existing control technologies installed. Therefore, it is important to understand heterogeneous Hg reaction mechanisms to predict the speciation of Hg emissions from coal-fired power plants to design and effectively determine the best applicable control technologies. In this work, theoretical and experimental investigations have been performed to investigate the adsorption and in some cases the oxidation, of Hg on solid surfaces, e.g., calcium oxide (CaO), noble metals and activated carbon (AC). The objective of this research is to identify potential materials that can be used as multi-pollutant sorbents in power plants by carrying out both high-level density functional theory (DFT) electronic structure calculations and experiments to understand heterogeneous chemical pathways of Hg. This research uses a fundamental science-based approach to understand the environmental problems caused by coal-fired energy production and provides solutions to the power generation industry for emissions reductions. Understanding the mechanism associated with Hg and SO2 adsorption on CaO will help to optimize the conditions or material to limit Hg emissions from the flue gas desulfurization process. Plane-wave DFT calculations were used to investigate the binding mechanism of Hg species and SO2 on the CaO(100) surface. The binding strengths on the high-symmetry CaO adsorption sites have been investigated for elemental Hg, SO2, mercury chlorides (HgCl and HgCl2) and mercuric oxide (HgO). It has been discovered that HgCl, HgCl2, and SO2 chemisorb on the CaO(100) surface at 0.125 ML coverage. Binding energies of elemental Hg are minimal indicating a physisorption mechanism. Noble metals such as palladium (Pd), gold (Au), silver (Ag), and copper (Cu) have been proposed to capture elemental Hg. Plane-wave DFT calculations have been carried out to investigate the mercury interactions with Pd binary alloys and overlays in addition to pure Pd, Au, Ag, and Cu surfaces. It has been determined that Pd has the highest mercury binding energy in comparison to other noble metals. In addition, Pd is found to be the primary surface atom responsible for increasing the adsorption of Hg with the surface in both Pd binary alloys and overlays. Deposition of Pd overlays on Au and Ag has been found to enhance the reactivity of the surface by shifting the d-states of surface atoms up in energy. The possible binding mechanisms of elemental Hg onto virgin, brominated and sulfonated AC fiber and brominated powder AC sorbents have been investigated through packed-bed experiments in a stream of air and simulated flue gas conditions, including SO2, hydrogen chloride (HCl), nitrogen oxide (NO) nitrogen dioxide (NO2). A combination of spectroscopy and plane-wave DFT calculations was used to characterize the sorption process. X-ray photoelectron spectroscopy (XPS) and x-ray absorption fine structure (XAFS) spectroscopy were used to analyze the surface and bulk chemical compositions of brominated AC sorbents reacted with Hg0. Through XPS surface characterization studies it was found that Hg adsorption is primarily associated with halogens on the surface. Elemental Hg is oxidized on AC surfaces and the oxidation state of adsorbed Hg is found to be Hg2+. Though plane-wave DFT and density of states (DOS) calculations indicate that Hg is more stable when it is bound to the edge carbon atom interacting with a single bromine bound atop of Hg, a model that includes an interaction between the Hg and an additional Br atom matches best with experimental data obtained from extended x-ray absorption fine structure (EXAFS) spectroscopy. The flue gas species such as HCl and bromine (Br2) enhance the Hg adsorption, while SO2 is found to decrease the Hg adsorption significantly by poisoning the active sites on the AC surface. The AC sorbents represent the most market-ready technology for Hg capture and therefore have been investigated by both theory and experiment in this work. Future work will include similar characterization and bench-scale experiments to test the metal-based materials for the sorbent and oxidation performance.
Author: Jiang Wu Publisher: Springer ISBN: 3662463474 Category : Technology & Engineering Languages : en Pages : 163
Book Description
Mercury (Hg) is one of the most toxic heavy metals, harmful to both the environment and human health. Hg is released into the atmosphere from natural and anthropogenic sources and its emission control has caused much concern. This book introduces readers to Hg pollution from natural and anthropogenic sources and systematically describes coal-fired flue gas mercury emission control in industry, especially from coal-fired power stations. Mercury emission control theory and experimental research are demonstrated, including how elemental mercury is oxidized into oxidized mercury and the effect of flue gas contents on the mercury speciation transformation process. Mercury emission control methods, such as existing APCDs (air pollution control devices) at power stations, sorbent injection, additives in coal combustion and photo-catalytic methods are introduced in detail. Lab-scale, pilot-scale and full-scale experimental studies of sorbent injection conducted by the authors are presented systematically, helping researchers and engineers to understand how this approach reduces the mercury emissions in flue gas and to apply the methods in mercury emission control at coal-fired power stations. Readers will arrive at a comprehensive understanding of various mercury emission control methods that are suitable for industrial applications. The book is intended for scientists, researchers, engineers and graduate students in the fields of energy science and technology, environmental science and technology and chemical engineering.
Author: Publisher: ISBN: Category : Languages : en Pages :
Book Description
As stated in the proposal: Ohio University, in collaboration with CONSOL Energy, Advanced Technology Systems, Inc (ATS) and Atmospheric and Environmental Research, Inc. (AER) as subcontractors, evaluated the impact of emissions from coal-fired power plants in the Ohio River Valley region as they relate to the transport and deposition of mercury and associated fine particulate matter. This evaluation involved two interrelated areas of effort: ambient air monitoring and regional-scale modeling analysis. The scope of work for the ambient air monitoring included the deployment of a surface air monitoring (SAM) station in southeastern Ohio. The SAM station contains sampling equipment to collect and measure mercury (including speciated forms of mercury and wet and dry deposited mercury), particulate matter (PM) mass, PM composition, and gaseous criteria pollutants (CO, NOx, SO2, O3, etc.). Laboratory analyses of time-integrated samples were used to obtain chemical speciation of ambient PM composition and mercury in precipitation. Nearreal- time measurements were used to measure the ambient concentrations of PM mass and all gaseous species including Hg0 and RGM. Approximately 30 months of field data were collected at the SAM site to validate the proposed regional model simulations for episodic and seasonal model runs. The ambient air quality data provides mercury, and fine particulate matter data that can be used by Ohio Valley industries to assess performance on multi-pollutant control systems. The scope of work for the modeling analysis includes (1) development of updated inventories of mercury emissions from coal plants and other important sources in the modeled domain; (2) adapting an existing 3-D atmospheric chemical transport model to incorporate recent advancements in the understanding of mercury transformations in the atmosphere; (3) analyses of the flux of Hg0, RGM, and fine particulate matter in the different sectors of the study region to identify key transport mechanisms; (4) comparison of cross correlations between species from the model results to observations in order to evaluate characteristics of specific air masses associated with long-range transport from a specified source region; and (5) evaluation of the sensitivity of these correlations to emissions from regions along the transport path. This is accomplished by multiple model runs with emissions simulations switched on and off from the various source regions. To the greatest extent possible, model results were compared to field data collected at other air monitoring sites in the Ohio Valley region, operated independently of this project. These sites may include (1) the DOE National Energy Technologies Laboratory's monitoring site at its suburban Pittsburgh, PA facility; (2) sites in Pittsburgh (Lawrenceville) PA and Holbrook, PA operated by ATS; (3) sites in Steubenville, OH and Pittsburgh, PA operated by the USEPA and/or its contractors; and (4) sites operated by State or local air regulatory agencies. Field verification of model results and predictions provides critical information for the development of cost effective air pollution control strategies by the coal-fired power plants in the Ohio River Valley region.
Author: Madhu Babu Puchakayala Publisher: ISBN: Category : Languages : en Pages :
Book Description
Of all the trace elements emitted during coal combustion, mercury is most problematic. Mercury from the atmosphere enters into oceanic and terrestrial waters. Part of the inorganic Hg in water is converted into organic Hg (CH3Hg), which is toxic and bioaccumulates in human and animal tissue. The largest source of human-caused mercury air emissions in the U.S is from combustion coal, a dominant fuel used for power generation. The Hg emitted from plants primarily occurs in two forms: elemental Hg and oxidized Hg (Hg2). The coal chlorine content and ash composition, gas temperature, residence time and presence of different gases will decide the speciation of Hg into Hg0 and Hg2. For Wyoming coal the concentrations of mercury and chlorine in coal are 120ppb and 140ppb. In order to understand the basic process of formulation of HgCl2 and Hg0 a numerical model is developed in the current work to simulate in the detail i) heating ii) transient pyrolysis of coal and evolution of mercury and chlorine, iii) gas phase oxidation iv) reaction chemistry of Hg and v) heterogeneous oxidation of carbon during isolated coal particle combustion. The model assumes that mercury and chlorine are released as a part of volatiles in the form of elemental mercury and HCl. Homogenous reaction are implemented for the oxidation of mercury. Heterogeneous Hg reactions are ignored. The model investigates the effect of different parameters on the extent of mercury oxidation; particle size, ambient temperature, volatile matter, blending coal with high chlorine coal and feedlot biomass etc, . Mercury oxidation is increased when the coal is blended with feedlot biomass and high chlorine coal and Hg % conversion to HgCl2 increased from 10% to 90% when 20% FB is blended with coal. The ambient temperature has a negative effect on mercury oxidation, an increase in ambient temperature resulted in a decrease in the mercury oxidation. The percentage of oxidized mercury increases from 9% to 50% when the chlorine concentration is increased from 100ppm to 1000ppm. When the temperature is decreased from 1950 K to 950 K, the percentage of mercury oxidized increased from 3% to 27%.
Author: Evan J. Granite Publisher: John Wiley & Sons ISBN: 3527658807 Category : Technology & Engineering Languages : en Pages : 479
Book Description
This essential handbook and ready reference offers a detailed overview of the existing and currently researched technologies available for the control of mercury in coal-derived gas streams and that are viable for meeting the strict standards set by environmental protection agencies. Written by an internationally acclaimed author team from government agencies, academia and industry, it details US, EU, Asia-Pacific and other international perspectives, regulations and guidelines.
Author: Erdem Sasmaz Publisher: ISBN: Category : Languages : en Pages :
Book Description
Coal-fired power plants are a major anthropogenic source of worldwide mercury (Hg) emissions. Since mercury is considered to be one of the most toxic metals found in the environment, Hg emissions from coal-fired power plants is of major environmental concern. Mercury in coal is vaporized into its gaseous elemental form throughout the coal combustion process. Elemental Hg can be oxidized in subsequent reactions with other gaseous components (homogeneous) and solid materials (heterogeneous) in coal-fired flue gases. While oxidized Hg in coal-fired flue gases is readily controlled by its adsorption onto fly ash and/or its dissolution into existing solution-based sulfur dioxide (SO2) scrubbers, elemental Hg is not controlled. The extent of elemental Hg formed during coal combustion is difficult to predict since it is dependent on the type of coal burned, combustion conditions, and existing control technologies installed. Therefore, it is important to understand heterogeneous Hg reaction mechanisms to predict the speciation of Hg emissions from coal-fired power plants to design and effectively determine the best applicable control technologies. In this work, theoretical and experimental investigations have been performed to investigate the adsorption and in some cases the oxidation, of Hg on solid surfaces, e.g., calcium oxide (CaO), noble metals and activated carbon (AC). The objective of this research is to identify potential materials that can be used as multi-pollutant sorbents in power plants by carrying out both high-level density functional theory (DFT) electronic structure calculations and experiments to understand heterogeneous chemical pathways of Hg. This research uses a fundamental science-based approach to understand the environmental problems caused by coal-fired energy production and provides solutions to the power generation industry for emissions reductions. Understanding the mechanism associated with Hg and SO2 adsorption on CaO will help to optimize the conditions or material to limit Hg emissions from the flue gas desulfurization process. Plane-wave DFT calculations were used to investigate the binding mechanism of Hg species and SO2 on the CaO(100) surface. The binding strengths on the high-symmetry CaO adsorption sites have been investigated for elemental Hg, SO2, mercury chlorides (HgCl and HgCl2) and mercuric oxide (HgO). It has been discovered that HgCl, HgCl2, and SO2 chemisorb on the CaO(100) surface at 0.125 ML coverage. Binding energies of elemental Hg are minimal indicating a physisorption mechanism. Noble metals such as palladium (Pd), gold (Au), silver (Ag), and copper (Cu) have been proposed to capture elemental Hg. Plane-wave DFT calculations have been carried out to investigate the mercury interactions with Pd binary alloys and overlays in addition to pure Pd, Au, Ag, and Cu surfaces. It has been determined that Pd has the highest mercury binding energy in comparison to other noble metals. In addition, Pd is found to be the primary surface atom responsible for increasing the adsorption of Hg with the surface in both Pd binary alloys and overlays. Deposition of Pd overlays on Au and Ag has been found to enhance the reactivity of the surface by shifting the d-states of surface atoms up in energy. The possible binding mechanisms of elemental Hg onto virgin, brominated and sulfonated AC fiber and brominated powder AC sorbents have been investigated through packed-bed experiments in a stream of air and simulated flue gas conditions, including SO2, hydrogen chloride (HCl), nitrogen oxide (NO) nitrogen dioxide (NO2). A combination of spectroscopy and plane-wave DFT calculations was used to characterize the sorption process. X-ray photoelectron spectroscopy (XPS) and x-ray absorption fine structure (XAFS) spectroscopy were used to analyze the surface and bulk chemical compositions of brominated AC sorbents reacted with Hg0. Through XPS surface characterization studies it was found that Hg adsorption is primarily associated with halogens on the surface. Elemental Hg is oxidized on AC surfaces and the oxidation state of adsorbed Hg is found to be Hg2+. Though plane-wave DFT and density of states (DOS) calculations indicate that Hg is more stable when it is bound to the edge carbon atom interacting with a single bromine bound atop of Hg, a model that includes an interaction between the Hg and an additional Br atom matches best with experimental data obtained from extended x-ray absorption fine structure (EXAFS) spectroscopy. The flue gas species such as HCl and bromine (Br2) enhance the Hg adsorption, while SO2 is found to decrease the Hg adsorption significantly by poisoning the active sites on the AC surface. The AC sorbents represent the most market-ready technology for Hg capture and therefore have been investigated by both theory and experiment in this work. Future work will include similar characterization and bench-scale experiments to test the metal-based materials for the sorbent and oxidation performance.
Author: Xiaofei Wang
Author: Xiaofei Wang
Author: Achariya Suriyawong
Author: Marina Smallwood
Author: 
Author: Erdem Sasmaz
Author: Jiang Wu
Author: 
Author: Madhu Babu Puchakayala
Author: Evan J. Granite
Author: Erdem Sasmaz