Microplastic pollution in the surface waters of the Laurentian Great Lakes.

PubMed

Eriksen, Marcus; Mason, Sherri; Wilson, Stiv; Box, Carolyn; Zellers, Ann; Edwards, William; Farley, Hannah; Amato, Stephen

2013-12-15

Neuston samples were collected at 21 stations during an ~700 nautical mile (~1300 km) expedition in July 2012 in the Laurentian Great Lakes of the United States using a 333 μm mesh manta trawl and analyzed for plastic debris. Although the average abundance was approximately 43,000 microplastic particles/km², station 20, downstream from two major cities, contained over 466,000 particles/km², greater than all other stations combined. SEM analysis determined nearly 20% of particles less than 1 mm, which were initially identified as microplastic by visual observation, were aluminum silicate from coal ash. Many microplastic particles were multi-colored spheres, which were compared to, and are suspected to be, microbeads from consumer products containing microplastic particles of similar size, shape, texture and composition. The presence of microplastics and coal ash in these surface samples, which were most abundant where lake currents converge, are likely from nearby urban effluent and coal burning power plants.

Assessment of tolerant sunfish populations (Lepomis sp.) inhabiting selenium-laden coal ash effluents. 3. Serum chemistry and fish health indicators.

PubMed

Lohner, T W; Reash, R J; Willet, V E; Fletcher, J

2001-11-01

Sunfish were collected from fly ash discharge-receiving streams to assess the possible effects of exposure to elevated selenium. Concentrations of selenium, copper, and arsenic were statistically higher in fish tissue (liver) samples from effluent-exposed fish than in reference fish. Several biomarkers were indicative of metal exposure and effect. Plasma protein levels and cholesterol levels were significantly lower in exposed fish, indicating nutritional stress. Ion levels (i.e., K) increased with exposure to ash pond metals, indicating possible gill damage. Fish from the receiving streams also had increased serum glucose and osmolality indicating possible acute stress due to sampling. Fish health assessments revealed a lower incidence of fin erosion, kidney discoloration, urolithiasis or nephrocalcinosis, liver discoloration, and parasites in exposed fish and a higher incidence of skin, eye, and gill aberrations. Condition factors of exposed fish were correlated with biomarker response and were the same as or lower than those of reference fish, but not related to selenium levels. Although several serum biochemical indicators differed between the ash pond-receiving stream and reference sites, pollutant exposure was apparently not sufficient to cause functional damage to critical organ systems.

Elaboration of new ceramic microfiltration membranes from mineral coal fly ash applied to waste water treatment.

PubMed

Jedidi, Ilyes; Saïdi, Sami; Khemakhem, Sabeur; Larbot, André; Elloumi-Ammar, Najwa; Fourati, Amine; Charfi, Aboulhassan; Salah, Abdelhamid Ben; Amar, Raja Ben

2009-12-15

This work aims to develop a new mineral porous tubular membrane based on mineral coal fly ash. Finely ground mineral coal powder was calcinated at 700 degrees C for about 3 h. The elaboration of the mesoporous layer was performed by the slip-casting method using a suspension made of the mixture of fly-ash powder, water and polyvinyl alcohol (PVA). The obtained membrane was submitted to a thermal treatment which consists in drying at room temperature for 24 h then a sintering at 800 degrees C. SEM photographs indicated that the membrane surface was homogeneous and did not present any macrodefects (cracks, etc...). The average pore diameter of the active layer was 0.25 microm and the thickness was around 20 microm. The membrane permeability was 475 l/h m(2) bar. This membrane was applied to the treatment of the dying effluents generated by the washing baths in the textile industry. The performances in term of permeate flux and efficiency were determined and compared to those obtained using a commercial alumina microfiltration membrane. Almost the same stabilised permeate flux was obtained (about 100 l h(-1)m(-2)). The quality of permeate was almost the same with the two membranes: the COD and color removal was 75% and 90% respectively.

Trace elements in lake sediment, macrozoobenthos, and fish near a coal ash disposal basin

USGS Publications Warehouse

Hatcher, Charles O.; Ogawa, Roann E.; Poe, Thomas P.; French, John R. P.

1992-01-01

Of the 29 trace elements examined, arsenic and cobalt were significantly (p <0.05) more concentrated in sediment nearest the coal ash basin except in spring, when little or no difference was detected. Arsenic and bromine were significantly higher in oligochaetes, and selenium was significantly higher in both oligochaetes and chironomids taken from proximal stations than in those taken from reference stations. Selenium, bromine, cobalt, nickel, and chromium were higher in young-of-the-year brown bullheads taken nearer the disposal basin in fall 1983. Selenium was higher in adult spottail shiners taken at the proximal station in spring 1984, and bromine was higher in yearling white bass from the proximal station in fall 1983 and 1984. None of the trace elements was higher in adult yellow perch or adult brown bullheads at any time. Fewer spottail shiners and yearling white bass were caught close to the disposal basin than far away, which may indicate avoidance by these fish of increased concentrations of trace elements contained within the ash effluent.

40 CFR 302.6 - Notification requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... transportation of coal and coal ash (including fly ash, bottom ash, and boiler slags), including the dumping and... coal and coal ash, including fly ash, bottom ash, and boiler slags. (d) Except for releases of..., chromium, copper, lead, nickel, selenium, silver, thallium, or zinc is not required if the mean diameter of...

Leaching characteristics of arsenic and selenium from coal fly ash: role of calcium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tian Wang; Jianmin Wang; Yulin Tang

2009-05-15

Understanding the leaching behavior of arsenic (As) and selenium (Se) in coal fly ash is important in evaluating the potential environmental impact of coal fly ash. Batch experiments were employed to systematically investigate the leaching behavior of As and Se in two major types of coal fly ashes, bituminous coal ash and sub-bituminous coal ash, and to determine the underlying processes that control As and Se leaching. The effects of pH, solid/liquid (S/L) ratio, calcium addition, and leaching time on the release of As and Se were studied. Overall, bituminous coal ash leached significantly more As and Se than sub-bituminousmore » coal ash, and Se was more readily leachable, in both absolute concentration and relative fraction, than As for both types of fly ashes. Adsorption/desorption played a major role on As and Se leaching from bituminous coal ashes. However, calcium precipitation played the most important role in reducing As and Se leaching from sub-bituminous coal ashes in the entire experimental pH range. The leaching of As and Se from bituminous coal ashes generally increased with increases in the S/L ratio and leaching time. However, for sub-bituminous coal ashes, the leaching of As was not detected under most experimental conditions, while the leaching of Se increased with increases in the S/L ratio and leaching time. As{sup V} and Se{sup IV} were found to be the major species in all ash leachates in this study. 46 refs., 7 figs., 1 tab.« less

The Wireless Sensor Network (WSN) Based Coal Ash Impoundments Safety Monitoring System

NASA Astrophysics Data System (ADS)

Sun, E. J.; Nieto, A.; Zhang, X. K.

2017-01-01

Coal ash impoundments are inevitable production of the coal-fired power plants. All coal ash impoundments in North Carolina USA that tested for groundwater contamination are leaking toxic heavy metals and other pollutants. Coal ash impoundments are toxic sources of dangerous pollutants that pose a danger to human and environmental health if the toxins spread to adjacent surface waters and drinking water wells. Coal ash impoundments failures accidents resulted in serious water contamination along with toxic heavy metals. To improve the design and stability of coal ash impoundments, the Development of a Coal Ash Impoundment Safety Monitoring System (CAISM) was proposed based on the implementation of a wireless sensor network (WSN) with the ability to monitor the stability of coal ash impoundments, water level, and saturation levels on-demand and remotely. The monitoring system based on a robust Ad-hoc network could be adapted to different safety conditions.

Ranking Coal Ash Materials for Their Potential to Leach Arsenic and Selenium: Relative Importance of Ash Chemistry and Site Biogeochemistry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schwartz, Grace E.; Hower, James C.; Phillips, Allison L.

The chemical composition of coal ash is highly heterogeneous and dependent on the origin of the source coal, combustion parameters, and type and configuration of air pollution control devices. This heterogeneity results in uncertainty in the evaluation of leaching potential of contaminants from coal ash. The goal of this work was to identify whether a single leaching protocol could roughly group high-leaching potential coal ash from low-leaching potential coal ash, with respect to arsenic (As) and selenium (Se). We used four different leaching tests, including the Toxicity Characteristic Leaching Protocol (TCLP), natural pH, aerobic sediment microcosms, and anaerobic sediment microcosmsmore » on 10 different coal ash materials, including fly ash, lime-treated ash, and flue gas desulfurization materials. Leaching tests showed promise in categorizing high and low-leaching potential ash materials, indicating that a single point test could act as a first screening measure to identify high-risk ash materials. However, the amount of contaminant leached varied widely across tests, reflecting the importance of ambient conditions (pH, redox state) on leaching. These results demonstrate that on-site geochemical conditions play a critical role in As and Se mobilization from coal ash, underscoring the need to develop a situation-based risk assessment framework for contamination by coal ash pollutants.« less

Ranking Coal Ash Materials for Their Potential to Leach Arsenic and Selenium: Relative Importance of Ash Chemistry and Site Biogeochemistry

DOE PAGES

Schwartz, Grace E.; Hower, James C.; Phillips, Allison L.; ...

2018-01-23

The chemical composition of coal ash is highly heterogeneous and dependent on the origin of the source coal, combustion parameters, and type and configuration of air pollution control devices. This heterogeneity results in uncertainty in the evaluation of leaching potential of contaminants from coal ash. The goal of this work was to identify whether a single leaching protocol could roughly group high-leaching potential coal ash from low-leaching potential coal ash, with respect to arsenic (As) and selenium (Se). We used four different leaching tests, including the Toxicity Characteristic Leaching Protocol (TCLP), natural pH, aerobic sediment microcosms, and anaerobic sediment microcosmsmore » on 10 different coal ash materials, including fly ash, lime-treated ash, and flue gas desulfurization materials. Leaching tests showed promise in categorizing high and low-leaching potential ash materials, indicating that a single point test could act as a first screening measure to identify high-risk ash materials. However, the amount of contaminant leached varied widely across tests, reflecting the importance of ambient conditions (pH, redox state) on leaching. These results demonstrate that on-site geochemical conditions play a critical role in As and Se mobilization from coal ash, underscoring the need to develop a situation-based risk assessment framework for contamination by coal ash pollutants.« less

Comparison of heterogeneous photolytic reduction of Hg(II) in the coal fly ashes and synthetic aerosols

NASA Astrophysics Data System (ADS)

Tong, Yindong; Eichhorst, Terry; Olson, Michael R.; Rutter, Andrew P.; Shafer, Martin M.; Wang, Xuejun; Schauer, James J.

2014-03-01

In this study, we examined the heterogeneous reduction of Hg(II) on the coal fly ash samples and synthetic aerosols under different light conditions in a controlled laboratory reactor. Three types of coal fly ashes were studied: a high carbon fly ash from a stoker boiler, a low carbon/low sulfate fly ash from a pulverized coal combustor burning low sulfur coal, and a high sulfate fly ash from a pulverized coal combustor burning high sulfur coal. The rate of Hg(II) reduction on the three diverse fly ash samples was found to be relatively fast with an average half-life of 1.6 h under clear sky atmospheric conditions (under the irradiance of 1000 W/m2). The reduction rate in the low sulfate/low carbon fly ash was approximately 1.5 times faster than with the other coal fly ash samples. Synthetic aerosols made of carbon black and levoglucosan produced Hg(II) reduction rates similar to coal fly ashes. However, aerosols composed of adipic acid resulted in reduction rates that were 3-5 times faster. The sensitivity of adipic acid reduction to light source wavelength was found to be greater than for the coal fly ash and other synthetic aerosols. Aerosols made from the water extracts of coal fly ash samples produced reduction rates equal to or slightly higher than with the native fly ash suggesting that the soluble components of fly ash play a significant role in the reduction mechanism. The measured reduction rates are likely important in the chemical processing of mercury in power plant plumes and potentially in the atmosphere and should be considered for incorporation in atmospheric transport models that are used to understand the fate of atmospheric mercury.

RADIOACTIVITY IN THE ATMOSPHERIC EFFLUENTS OF POWER PLANTS THAT USE FOSSIL FUELS.

PubMed

EISENBUD, M; PETROW, H G

1964-04-17

Analysis of the fly ash produced by combustion of pulverized Appalachian coal has shown that a 1000-megawatt coal-burning power plant will discharge into the atmosphere from about 28 millicuries to nearly 1 curie per year of radium-226 and radium-228. An oil-burning plant of similar size will discharge about 0.5 millicurie of radium per year. Comparison of these data with data on the release of fission products from nuclear-powered generating stations shows that when the physical and biological properties of the various radionuclides are taken into consideration, the conventional fossil-fueled plants discharge relatively greater quantities of radioactive materials into the atmosphere than nuclearpowered plants of comparable size.

Cohering Behavior of Coal Ash with Pellet Scrap Powder and Relationship Between Coal Ash and Kiln Ringing

NASA Astrophysics Data System (ADS)

Yang, Yong-bin; Zhang, Yan; Zhong, Qiang; Jiang, Tao; Li, Qian; Xu, Bin

The occurrence of different ringing behaviors in oxidized pellet kiln for two kinds of coal (A and B) with similar properties, is difficult to explain based on the relationship between kiln ringing and coal properties. In this paper, the interaction of coal ash with pellet scrap powder was considered by studying the cohering behavior of powders consisting of them. The results showed that the cohering briquette strength of pellet scrap powder increased considerably when mixed with a small amount of coal ash; a maximum could be reached when the mass percent ratio of coal ash was 1.5%; the strength of powder mixed with coal B ash was always higher in same firing system. This obviously illustrated that coal B caused a more serious ringing problem. The relevant mechanism was that the stronger reactivity of coal B ash made cohering briquette have a more perfect crystallization and a more compact structure.

Chemical composition and some trace element contents in coals and coal ash from Tamnava-Zapadno Polje Coal Field, Serbia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vukasinovic-Pesic, V.; Rajakovic, L.J.

2009-07-01

The chemical compositions and trace element contents (Zn, Cu, Co, Cr, Ni, Pb, Cd, As, B, Hg, Sr, Se, Be, Ba, Mn, Th, V, U) in coal and coal ash samples from Tamnava-Zapadno Polje coal field in Serbia were studied. The coal from this field belongs to lignite. This high volatility coal has high moisture and low S contents, moderate ash yield, and high calorific value. The coal ash is abundant in alumosilicates. Many trace elements such as Ni > Cd > Cr > B > As > Cu > Co > Pb > V > Zn > Mn inmore » the coal and Ni > Cr > As > B > Cu > Co = Pb > V > Zn > Mn in the coal ash are enriched in comparison with Clarke concentrations.« less

Evaluation of Pollutant Leaching Potential of Coal Ashes for Recycling

NASA Astrophysics Data System (ADS)

Park, D.; Woo, N. C.; Kim, H.; Yoon, H.; Chung, D.

2011-12-01

By 2009, coal ashes produced from coal-based power plants in Korea have been reused as cement supplement materials; however, the rest is mostly disposed in landfills inside the plant properties. Continuous production of coal ashes and limited landfill sites require more recycles of coal ashes as base materials, specifically in constructions of roads and of huge industrial complex. Previous researches showed that coal ashes could contain various metals such as arsenic(As), chromium(Cr), lead(Pb), nickel(Ni), selenium(Se), etc. In this study, we collected four types of bottom ashes and two of fly ashes from four coal-based power plants. These ash samples were tested with distilled water through the column leaching process in oxidized conditions. The column test results were compared with those of total digestion, sequential extraction processes and TCLP. Concentrations of metals in outflows from columns are generally greater in fly ashes than in bottom ashes, specifically for As, Se, B, Sr and SO4. Only one fly ash (J2-F) shows high concentrations of arsenic and selenium in leachate. Sequential extraction results indicate that these metals are in readily soluble forms, such as adsorbed, carbonated, and reducible forms. Results of TCLP analysis indicate no potential contaminants leached from the ashes. In conclusion, recycling of coal combustion ashes could be encouraged with proper tests such as sequential and leaching experiments.

Correlation between the critical viscosity and ash fusion temperatures of coal gasifier ashes

DOE PAGES

Hsieh, Peter Y.; Kwong, Kyei-Sing; Bennett, James

2015-09-27

Coal gasification yields synthesis gas, an important intermediate in chemical manufacturing. It is also vital to the production of liquid fuels through the Fischer-Tropsch process and electricity in Integrated Gasification Combined Cycle power generation. Minerals naturally present in coal become molten in entrained-flow slagging gasifiers. Molten coal ash slag penetrates and dissolves refractory bricks, leading to costly plant shutdowns. The extent of coal ash slag penetration and refractory brick dissolution depends on the slag viscosity, the gasification temperature, and the composition of slag and bricks. We measured the viscosity of several synthetic coal ash slags with a high-temperature rotary viscometermore » and their ash fusion temperatures through optical image analysis. All measurements were made in a carbon monoxide-carbon dioxide reducing atmosphere that approximates coal gasification conditions. Empirical correlation models based on ash fusion temperatures were used to calculate critical viscosity temperatures based on the coal ash compositions. These values were then compared with those obtained from thermodynamic phase-transition models. An understanding of slag viscosity as a function of ash composition is important to reducing refractory wear in slagging coal gasifiers, which would help to reduce the cost and environmental impact of coal for chemical and electricity production.« less

Correlation between the critical viscosity and ash fusion temperatures of coal gasifier ashes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hsieh, Peter Y.; Kwong, Kyei-Sing; Bennett, James

Coal gasification yields synthesis gas, an important intermediate in chemical manufacturing. It is also vital to the production of liquid fuels through the Fischer-Tropsch process and electricity in Integrated Gasification Combined Cycle power generation. Minerals naturally present in coal become molten in entrained-flow slagging gasifiers. Molten coal ash slag penetrates and dissolves refractory bricks, leading to costly plant shutdowns. The extent of coal ash slag penetration and refractory brick dissolution depends on the slag viscosity, the gasification temperature, and the composition of slag and bricks. We measured the viscosity of several synthetic coal ash slags with a high-temperature rotary viscometermore » and their ash fusion temperatures through optical image analysis. All measurements were made in a carbon monoxide-carbon dioxide reducing atmosphere that approximates coal gasification conditions. Empirical correlation models based on ash fusion temperatures were used to calculate critical viscosity temperatures based on the coal ash compositions. These values were then compared with those obtained from thermodynamic phase-transition models. An understanding of slag viscosity as a function of ash composition is important to reducing refractory wear in slagging coal gasifiers, which would help to reduce the cost and environmental impact of coal for chemical and electricity production.« less

The leaching characteristics of selenium from coal fly ashes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, T.; Wang, J.; Burken, J.G.

2007-11-15

The leaching characteristics of selenium from several bituminous and subbituminous coal fly ashes under different pH conditions were investigated using batch methods. Results indicated that pH had a significant effect on selenium leaching from bituminous coal ash. The minimum selenium leaching occurred in the pH range between 3 and 4, while the maximum selenium leaching occurred at pH 12. The release of selenium from subbituminous coal ashes was very low for the entire experimental pH range, possibly due to the high content of calcium which can form hydration or precipitation products as a sink for selenium. The adsorption results formore » different selenium species indicated that Se(VI) was hardly adsorbable on either bituminous coal ashes or subbitumminous coal ashes at any pH. However, Se(I) was highly adsorbed by bituminous coal ashes under acidic pH conditions and was mostly removed by subbitumminous coal ashes across the entire pH range. This result suggests that the majority of selenium released from the tested fly ashes was Se(IV). A speciation-based model was developed to simulate the adsorption of Se(IV) on bituminous coal fly ash, and the pH-independent adsorption constants of HSeO{sup 3-} and SeO{sub 3}{sup 2-} were determined. The modeling approach is useful for understanding and predicting the release process of selenium from fly ash.« less

Size distribution of rare earth elements in coal ash

USGS Publications Warehouse

Scott, Clinton T.; Deonarine, Amrika; Kolker, Allan; Adams, Monique; Holland, James F.

2015-01-01

Rare earth elements (REEs) are utilized in various applications that are vital to the automotive, petrochemical, medical, and information technology industries. As world demand for REEs increases, critical shortages are expected. Due to the retention of REEs during coal combustion, coal fly ash is increasingly considered a potential resource. Previous studies have demonstrated that coal fly ash is variably enriched in REEs relative to feed coal (e.g, Seredin and Dai, 2012) and that enrichment increases with decreasing size fractions (Blissett et al., 2014). In order to further explore the REE resource potential of coal ash, and determine the partitioning behavior of REE as a function of grain size, we studied whole coal and fly ash size-fractions collected from three U.S commercial-scale coal-fired generating stations burning Appalachian or Powder River Basin coal. Whole fly ash was separated into , 5 um, to 5 to 10 um and 10 to 100 um particle size fractions by mechanical shaking using trace-metal clean procedures. In these samples REE enrichments in whole fly ash ranges 5.6 to 18.5 times that of feedcoals. Partitioning results for size separates relative to whole coal and whole fly ash will also be reported. 

Leaching characteristics of toxic constituents from coal fly ash mixed soils under the influence of pH.

PubMed

Komonweeraket, Kanokwan; Cetin, Bora; Benson, Craig H; Aydilek, Ahmet H; Edil, Tuncer B

2015-04-01

Leaching behaviors of Arsenic (As), Barium (Ba), Calcium (Ca), Cadmium (Cd), Magnesium (Mg), Selenium (Se), and Strontium (Sr) from soil alone, coal fly ash alone, and soil-coal fly ash mixtures, were studied at a pH range of 2-14 via pH-dependent leaching tests. Seven different types of soils and coal fly ashes were tested. Results of this study indicated that Ca, Cd, Mg, and Sr showed cationic leaching pattern while As and Se generally follows an oxyanionic leaching pattern. On the other hand, leaching of Ba presented amphoteric-like leaching pattern but less pH-dependent. In spite of different types and composition of soil and coal fly ash investigated, the study reveals the similarity in leaching behavior as a function of pH for a given element from soil, coal fly ash, and soil-coal fly ash mixtures. The similarity is most likely due to similar controlling mechanisms (e.g., solubility, sorption, and solid-solution formation) and similar controlling factors (e.g., leachate pH and redox conditions). This offers the opportunity to transfer knowledge of coal fly ash that has been extensively characterized and studied to soil stabilized with coal fly ash. It is speculated that unburned carbon in off-specification coal fly ashes may provide sorption sites for Cd resulting in a reduction in concentration of these elements in leachate from soil-coal fly ash mixture. Class C fly ash provides sufficient CaO to initiate the pozzolanic reaction yielding hydrated cement products that oxyanions, including As and Se, can be incorporated into. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Sequential Application of Macroalgal Biosorbents for the Bioremediation of a Complex Industrial Effluent

PubMed Central

Kidgell, Joel T.; de Nys, Rocky; Paul, Nicholas A.; Roberts, David A.

2014-01-01

Fe-treated biochar and raw biochar produced from macroalgae are effective biosorbents of metalloids and metals, respectively. However, the treatment of complex effluents that contain both metalloid and metal contaminants presents a challenging scenario. We test a multiple-biosorbent approach to bioremediation using Fe-biochar and biochar to remediate both metalloids and metals from the effluent from a coal-fired power station. First, a model was derived from published data for this effluent to predict the biosorption of 21 elements by Fe-biochar and biochar. The modelled outputs were then used to design biosorption experiments using Fe-biochar and biochar, both simultaneously and in sequence, to treat effluent containing multiple contaminants in excess of water quality criteria. The waste water was produced during ash disposal at an Australian coal-fired power station. The application of Fe-biochar and biochar, either simultaneously or sequentially, resulted in a more comprehensive remediation of metalloids and metals compared to either biosorbent used individually. The most effective treatment was the sequential use of Fe-biochar to remove metalloids from the waste water, followed by biochar to remove metals. Al, Cd, Cr, Cu, Mn, Ni, Pb, Zn were reduced to the lowest concentration following the sequential application of the two biosorbents, and their final concentrations were predicted by the model. Overall, 17 of the 21 elements measured were remediated to, or below, the concentrations that were predicted by the model. Both metalloids and metals can be remediated from complex effluent using biosorbents with different characteristics but derived from a single feedstock. Furthermore, the extent of remediation can be predicted for similar effluents using additive models. PMID:25061756

Integrated coal cleaning, liquefaction, and gasification process

DOEpatents

Chervenak, Michael C.

1980-01-01

Coal is finely ground and cleaned so as to preferentially remove denser ash-containing particles along with some coal. The resulting cleaned coal portion having reduced ash content is then fed to a coal hydrogenation system for the production of desirable hydrocarbon gases and liquid products. The remaining ash-enriched coal portion is gasified to produce a synthesis gas, the ash is removed from the gasifier usually as slag, and the synthesis gas is shift converted with steam and purified to produce the high purity hydrogen needed in the coal hydrogenation system. This overall process increases the utilization of as-mined coal, reduces the problems associated with ash in the liquefaction-hydrogenation system, and permits a desirable simplification of a liquids-solids separation step otherwise required in the coal hydrogenation system.

COAL-FIRED POWER PLANT ASH UTILIZATION IN THE TVA REGION

EPA Science Inventory

The report gives results of a study: (1) to summarize (a) production of coal ash nationally and by TVA's 12 major ash-producing steam/electric power plants, and (b) the physical/chemical characteristics of coal ash that affect ash disposal and/or use; (2) to review reported metho...

The secondary release of mercury in coal fly ash-based flue-gas mercury removal technology.

PubMed

He, Jingfeng; Duan, Chenlong; Lei, Mingzhe; Zhu, Xuemei

2016-01-01

The secondary release of mercury from coal fly ash is a negative by-product from coal-fired power plants, and requires effective control to reduce environmental pollution. Analysing particle size distribution and composition of the coal fly ash produced by different mercury removing technologies indicates that the particles are generally less than 0.5 mm in size and are composed mainly of SiO2, Al2O3, and Fe2O3. The relationships between mercury concentration in the coal fly ash, its particle size, and loss of ignition were studied using different mercury removing approaches. The research indicates that the coal fly ash's mercury levels are significantly higher after injecting activated carbon or brominating activated carbon when compared to regular cooperating-pollution control technology. This is particularly true for particle size ranges of >0.125, 0.075-0.125, and 0.05-0.075 mm. Leaching experiments revealed the secondary release of mercury in discarded coal fly ash. The concentration of mercury in the coal fly ash increases as the quantity of injecting activated carbon or brominating activated carbon increases. The leached concentrations of mercury increase as the particle size of the coal fly ash increases. Therefore, the secondary release of mercury can be controlled by adding suitable activated carbon or brominating activated carbon when disposing of coal fly ash. Adding CaBr2 before coal combustion in the boiler also helps control the secondary release of mercury, by increasing the Hg(2+) concentration in the leachate. This work provides a theoretical foundation for controlling and removing mercury in coal fly ash disposal.

Physical and biological studies of coal and oil fly ash.

PubMed Central

Fisher, G L; McNeill, K L; Prentice, B A; McFarland, A R

1983-01-01

Studies were performed to compare the physical and chemical characteristics and the in vitro macrophage cytotoxicity of oil and coal fly ash. Sampling methodology was developed to collect size-fractionated particulate matter from the smokestack of either a coal-fired or an oil-fired power plant. Morphological studies demonstrated particle heterogeneity, although most coal fly ash particles appeared to be spherical. Oil fly ash contained two major morphologies; nonopaque amorphous particles and opaque amorphous particles. Elemental analysis indicates that the coal ash is predominantly composed of aluminosilicate particles, while the oil ash is predominantly inorganic sulfates and carbonaceous particles. In vitro macrophage assays demonstrate that the finest coal fly ash particles are the most cytotoxic; the cytotoxicity is significantly less than that of alpha-quartz, the positive control particle. In contrast, the oil fly ash particles are more cytotoxic than quartz. The cytotoxicity of oil fly ash is due to soluble components, possibly vanadium salts. Images FIGURE 2. A FIGURE 2. B FIGURE 2. C FIGURE 2. D PMID:6641653

From in-situ coal to fly ash: A study of coal mines and power plants from Indiana

USGS Publications Warehouse

Mastalerz, Maria; Hower, J.C.; Drobniak, A.; Mardon, S.M.; Lis, G.

2004-01-01

This paper presents data on the properties of coal and fly ash from two coal mines and two power plants that burn single-source coal from two mines in Indiana. One mine is in the low-sulfur (5%) Springfield Coal Member of the Petersburg Formation (Pennsylvanian). Both seams have comparable ash contents (???11%). Coals sampled at the mines (both raw and washed fractions) were analyzed for proximate/ultimate/sulfur forms/heating value, major oxides, trace elements and petrographic composition. The properties of fly ash from these coals reflect the properties of the feed coal, as well as local combustion and post-combustion conditions. Sulfur and spinel content, and As, Pb and Zn concentrations of the fly ash are the parameters that most closely reflect the properties of the source coal. ?? 2004 Elsevier B.V. All rights reserved.

Leaching characteristics of toxic constituents from coal fly ash mixed soils under the influence of pH

DOE Office of Scientific and Technical Information (OSTI.GOV)

Komonweeraket, Kanokwan; Cetin, Bora, E-mail: bora.cetin@sdsmt.edu; Benson, Craig H., E-mail: chbenson@wisc.edu

Highlights: • The impact of pH on the leaching of elements and metals from fly ash mixed soils. • Generally Ca, Cd, Mg, and Sr follows a cationic leaching pattern. • The leaching of As and Se shows an oxyanionic leaching pattern. • The leaching behavior of elements does not change based on material type. • Different fly ash types show different abilities in immobilizing trace elements. - Abstract: Leaching behaviors of Arsenic (As), Barium (Ba), Calcium (Ca), Cadmium (Cd), Magnesium (Mg), Selenium (Se), and Strontium (Sr) from soil alone, coal fly ash alone, and soil-coal fly ash mixtures, weremore » studied at a pH range of 2–14 via pH-dependent leaching tests. Seven different types of soils and coal fly ashes were tested. Results of this study indicated that Ca, Cd, Mg, and Sr showed cationic leaching pattern while As and Se generally follows an oxyanionic leaching pattern. On the other hand, leaching of Ba presented amphoteric-like leaching pattern but less pH-dependent. In spite of different types and composition of soil and coal fly ash investigated, the study reveals the similarity in leaching behavior as a function of pH for a given element from soil, coal fly ash, and soil-coal fly ash mixtures. The similarity is most likely due to similar controlling mechanisms (e.g., solubility, sorption, and solid-solution formation) and similar controlling factors (e.g., leachate pH and redox conditions). This offers the opportunity to transfer knowledge of coal fly ash that has been extensively characterized and studied to soil stabilized with coal fly ash. It is speculated that unburned carbon in off-specification coal fly ashes may provide sorption sites for Cd resulting in a reduction in concentration of these elements in leachate from soil-coal fly ash mixture. Class C fly ash provides sufficient CaO to initiate the pozzolanic reaction yielding hydrated cement products that oxyanions, including As and Se, can be incorporated into.« less

An experimental study on the hazard assessment and mechanical properties of porous concrete utilizing coal bottom ash coarse aggregate in Korea.

PubMed

Park, Seung Bum; Jang, Young Il; Lee, Jun; Lee, Byung Jae

2009-07-15

This study evaluates quality properties and toxicity of coal bottom ash coarse aggregate and analyzes mechanical properties of porous concrete depending on mixing rates of coal bottom ash. As a result, soundness and resistance to abrasion of coal bottom ash coarse aggregate were satisfied according to the standard of coarse aggregate for concrete. To satisfy the standard pertaining to chloride content, the coarse aggregates have to be washed more than twice. In regards to the result of leaching test for coal bottom ash coarse aggregate and porous concrete produced with these coarse aggregates, it was satisfied with the environment criteria. As the mixing rate of coal bottom ash increased, influence of void ratio and permeability coefficient was very little, but compressive and flexural strength decreased. When coal bottom ash was mixed over 40%, strength decreased sharply (compressive strength: by 11.7-27.1%, flexural strength: by maximum 26.4%). Also, as the mixing rate of coal bottom ash increased, it was confirmed that test specimens were destroyed by aggregate fracture more than binder fracture and interface fracture. To utilize coal bottom ash in large quantities, it is thought that an improvement method in regards to strength has to be discussed such as incorporation of reinforcing materials and improvement of aggregate hardness.

The energy-water quality nexus: insights from the 2008 coal ash spill in Tennessee

NASA Astrophysics Data System (ADS)

Vengosh, A.; Ruhl, L.; Dwyer, G. S.; Hsu-Kim, H.; Deonarine, A.

2010-12-01

Energy production consumes a large volume of water. The USGS estimated that about 52 percent of the total USA fresh surface-water withdrawal in 2000 was for thermoelectric consumption (fresh water use ~188 for thermoelectric out of 563 billion cubic meters a year total water withdrawal in the USA). While water availability and possible changes induced from climate change and increasing demands for other sectors are important limiting factors, this presentation highlights the critical long-term impact on water quality. The Clean Smokestacks Act was enacted to reduce emissions from coal-fired power plants through installation of scrubbers and selective catalytic reduction, aiming to cut emissions of sulfur dioxide, nitrogen oxides and mercury. In addition to the capture of these air pollutants, volatile elements are attached to the residual coal combustion products (CCPs). Consequently, toxic metals concentrations in CCPs are extremely high and become mobile upon interaction of CCPs with aquatic solutions. In particular, several studies have demonstrated the high mobilization of boron, arsenic, selenium, barium and other toxic oxi-anions and metals from CCPs. The 2008 coal ash spill in Kingston, Tennessee, where approximately 4.1 million cubic meters of coal ash was spilled onto the surrounding land surface and into the adjacent Emory and Clinch Rivers, has demonstrated the possible impact of CCPs on the environment. An eighteen-month survey has revealed elevated levels of contaminants in surface water with restricted water exchange and in pore water extracted from the bottom sediments, downstream from the spill. Our research has shown that arsenic concentration in the pore water reached to 2,000 ppb due to the reducing conditions and the high mobility of the non-charged arsenic species. Generation of CCPs however is not restricted to a single accidental release, as over five hundred power plants nationwide generate approximately 130 million tons of CCPs each year, in which more than half is stored in 194 landfills and 161 holding ponds. In each of these sites effluents that are generated from leaching of CCPs could contain high levels of contaminants that could pose severe ecological hazards to the local aquatic systems. Preliminary results from Hyco Lake in North Carolina have demonstrated high levels of toxic metals in effluents that are generated from adjacent coal-fired plant combined with high boron concentrations (1000 ppb) in the fresh lake water. The notion that CCPs generates a direct threat to the aquatic systems through holding ponds, landfills, or even “beneficial use” in sites where CCPs could be exposed and interact with the ambient environment should become an additional factor in evaluating the cost of “cheap coal” and its impact on the environment.

Review: Application of coal bottom ash as aggregate replacement in highway embankment, acoustic absorbing wall and asphalt mixtures

NASA Astrophysics Data System (ADS)

Afiza Mohammed, Syakirah; Rehan Karim, Mohamed

2017-06-01

Worldwide annual production of coal bottom ash waste was increased in the last decade and is being dumped on landfill over the years. Its improper disposal has become an environmental concern and resulted in a waste of recoverable resources. There is a pressing and on-going need to develop new recycling methods for coal bottom ash. The utilization of coal bottom ash in highway engineering is one of the options to reduce the environmental problems related to the disposal of bottom ash. The present review describe the physical and chemical properties of coal bottom ash waste and its current application as highway embankment material, as acoustic absorbing material and as aggregate replacement in asphalt mixtures. The purpose of this review is to stimulate and promote the effective recycling of coal bottom ash in highway engineering industry.

Research on dispose of wastewater from printing and dyeing by CWF combined with Iron-carbon Microelectrolysis

NASA Astrophysics Data System (ADS)

Chen, Xin; Ye, Tingjin; Xu, Zizhen; Chen, Xiaogang; Shi, Liang; He, Lingfeng; Zhang, Yongli

2018-03-01

The carboxymethylchitosan cladding coal ash (CWF) was oxidized by the high temperature using coal ash and sodium carboxymethyl chitosan as raw and processed material for treatment of simulated and actual printing and dyeing wastewater over iron-carbon micro-electrolysis. The results on pH and CWF dosage for effluent dispose were evaluated by the decolorization rate, COD removal efficiency and turbidity removal rate. The experimental results indicated that the decolorization rate was first augmented and then declined with the increase of pH, and attained a peak value when pH was at 5-6. The COD removal efficiency augmented with the augmented of pH, and attained a peak value when pH was 6-7. The turbidity removal rate was first increases and afterwards decreases with the augment of pH, and attained a peak value when pH was at 5-6. Furthermore, the optimum pH for the treatment of simulated dyeing wastewater was 6 over iron-carbon micro-electrolysis, which indicated that the appropriate pH can promote the degradation of wastewater.

Performance of double-layer biofilter packed with coal fly ash ceramic granules in treating highly polluted river water.

PubMed

Jing, Zhaoqian; Li, Yu-You; Cao, Shiwei; Liu, Yuyu

2012-09-01

To improve trickling filters' denitrification efficiency, a biofilter with a trickling upper layer and a submerged lower layer was developed and applied in treating highly polluted river water. It was packed with porous coal fly ash ceramic granules. Its start-up characteristics, influence of hydraulic loading rates (HLR), carbon/nitrogen (C/N) ratio and filter depth on pollutants removal were investigated. The results indicated this biofilter was started quickly in 16 days with river sediment as inoculum. Alternating nitrification and denitrification were achieved when water flowed downwards. COD and nitrogen were mainly removed in the upper layer and the lower layer, respectively. With HLR of 4.0-5.0m(3)/(m(2)d), chemical oxygen demand (COD), ammonium (NH(4)(+)-N) and total nitrogen (TN) in the effluent were below 50, 5 and 15 mg/L, respectively. This biofilter removed more than 80% of COD, 85% of NH(4)(+)-N and 60% of TN with C/N ratios ranging from 6 to 10. Copyright © 2012 Elsevier Ltd. All rights reserved.

Utilization of western coal fly ash in construction of highways in the Midwest

DOT National Transportation Integrated Search

2000-03-01

Coal burning utilities in the Midwest are increasingly using sub-bituminous coal from Wyoming. These utilities typically produce fly ash, which, because of its high calcium oxide content, may be classified as Class C fly ash. These ashes are characte...

Cytotoxicity and genotoxicity induced by coal and coal fly ash particles samples in V79 cells.

PubMed

León-Mejía, Grethel; Silva, Luis F O; Civeira, Matheus S; Oliveira, Marcos L S; Machado, Miriana; Villela, Izabel Vianna; Hartmann, Andreas; Premoli, Suziane; Corrêa, Dione Silva; Da Silva, Juliana; Henriques, João Antônio Pêgas

2016-12-01

Exposure to coal and coal ashes can cause harmful effects in in vitro and in vivo systems, mainly by the induction of oxidative damage. The aim of this work was to assess cytotoxic and genotoxic effects using the V79 cell line treated with coal and coal fly ash particles derived from a coal power plant located in Santa Catarina, Brazil. Two coal samples (COAL11 and COAL16) and two coal fly ash samples (CFA11 and CFA16) were included in this study. COAL16 was co-firing with a mixture of fuel oil and diesel oil. The comet assay data showed that exposure of V79 cells to coal and coal fly ash particles induced primary DNA lesions. Application of lesion-specific endonucleases (FPG and ENDO III) demonstrated increased DNA effects indicating the presence of high amounts of oxidative DNA lesions. The cytokinesis-block micronucleus cytome assay analysis showed that exposure of V79 cells to high concentrations of coal and coal fly ash particles induced cytotoxic effects (apoptosis and necrosis) and chromosomal instability (nucleoplasmic bridges, nuclear buds, and micronucleus (MN) formation). These results may be associated with compounds contained in the surface of the particles as hazardous elements, ultrafine/nanoparticles, and polycyclic aromatic hydrocarbons (PAHs) which were detected in the samples. Graphical abstract ᅟ.

Human and Environmental Dangers Posed by Ongoing Global Tropospheric Aerosolized Particulates for Weather Modification.

PubMed

Herndon, J Marvin

2016-01-01

U.S. military perception of nuclear warfare led to countless unethical nuclear experiments performed on unsuspecting individuals without their informed consent. As evidenced here, subsequent perception of weather warfare has led to exposing millions of unsuspecting individuals to toxic coal fly ash with no public disclosure, no informed consent, and no health warnings. Three methods were used: (1) comparison of eight elements analyzed in rainwater samples, thought to have leached from aerosolized coal fly ash, with corresponding coal fly ash laboratory leachate; (2) comparison of 14 elements analyzed in air filter dust with corresponding elements in coal fly ash; and (3) comparison of 23 elements analyzed in fibrous mesh found after snow melted with corresponding elements in coal fly ash. The rainwater element ratios show that the aerial particulate matter has essentially the same water-leach characteristics as coal fly ash. The air filter dust element ratios occur in the same range of compositions as coal fly ash, as do element ratios in fibrous mesh found on grass after snow melted. The fibrous mesh provides an inferred direct connection with the aerosolizing jet aircraft via coal fly ash association with the jet combustion environment. Strong evidence for the correctness of the hypothesis: coal fly ash is likely the aerosolized particulate emplaced in the troposphere for geoengineering, weather modification, and/or climate alteration purposes. The documented public health associations for ≤2.5 μm particulate pollution are also applicable to aerosolized coal fly ash. The ability of coal fly ash to release aluminum in a chemically mobile form upon exposure to water or body moisture has potentially grave human and environmental consequences over a broad spectrum, including implications for neurological diseases and biota debilitation. The ability of coal fly ash to release heavy metals and radioactive elements upon exposure to body moisture has potentially grave human health implications including cancer, cardiovascular disease, diabetes, respiratory diseases, reduced male fertility, and stroke. The fibrous mesh data admit the possibility of environmentally disastrous formation of methylmercury and ozone-depleting chlorinated-fluorinated hydrocarbons in jet exhaust. Geophysical implications include atmospheric warming and rainfall retardation.

Characterization and modes of occurrence of elements in feed coal and fly ash; an integrated approach

USGS Publications Warehouse

Brownfield, M.E.

2002-01-01

Despite certain environmental concerns, coal is likely to remain an important component of the United States energy supply, partly because it is the most abundant domestically available fossil fuel. One of the concerns about coal combustion for electricity production is the potential release of elements from coal and coal combustion products (CCPs) - fly ash - to the environment. This concern prompted the need for accurate, reliable, and comprehensive information on the contents and modes of occurrence of selected elements in power-plant feed coal and fly ash. The U.S. Geological Survey (USGS) is collaborating with several electric utilities to determine the chemical and mineralogical properties of feed coal and fly ash. Our first study analyzed coal and fly ash from a Kentucky power plant, which uses many different bituminous coals from the Appalachian and Illinois Basins. Sulfur content of these feed coals rangedfrom 2.5 to 3.5 percent. The second study analyzed coal and fly ash from an Indiana power plant, which uses subbituminous coal from the Powder River Basin (fig. 1). Sulfur content of this feed coal ranged from 0.23 to 0.47 percent. A summary of important aspects of our approach and results are presented in this report. 

Evaluation of heavy metal leaching from coal ash-versus conventional concrete monoliths and debris.

PubMed

Gwenzi, Willis; Mupatsi, Nyarai M

2016-03-01

Application of coal ash in construction materials is constrained by the potential risk of heavy metal leaching. Limited information is available on the comparative heavy metal leaching from coal ash-versus conventional concrete. The current study compared total and leached heavy metal concentrations in unbound coal ash, cement and sand; and investigated the effect of initial leachant pH on heavy metal leaching from coal-ash versus conventional concrete monoliths and their debris. Total Pb, Mn and Zn in coal ash were lower than or similar to that of other materials, while Cu and Fe showed the opposite trend. Leached concentrations of Zn, Pb, Mn, Cu and Fe in unbound coal ash, its concrete and debris were comparable and in some cases even lower than that for conventional concrete. In all cases, leached concentrations accounted for just <1% of the total concentrations. Log-log plots of concentration and cumulative release of Fe versus time based on tank leaching data showed that leaching was dominated by diffusion. Overall, the risk of Zn, Pb, Mn, Cu and Fe leaching from coal ash and its concrete was minimal and comparable to that of conventional concrete, a finding in contrast to widely held public perceptions and earlier results reported in other regions such as India. In the current study the coal ash, and its concrete and debris had highly alkaline pH indicative of high acid neutralizing and pH buffering capacity, which account for the stabilization of Zn, Pb, Mn, Cu and Fe. Based on the low risk of Zn, Pb, Mn, Cu and Fe leaching from the coal ash imply that such coal ash can be incorporated in construction materials such as concrete without adverse impacts on public and environmental health from these constituents. Copyright © 2015 Elsevier Ltd. All rights reserved.

Geotechnical approaches to coal ash content control in mining of complex structure deposits

NASA Astrophysics Data System (ADS)

Batugin, SA; Gavrilov, VL; Khoyutanov, EA

2017-02-01

Coal deposits having complex structure and nonuniform quality coal reserves require improved processes of production quality control. The paper proposes a method to present coal ash content as components of natural and technological dilution. It is chosen to carry out studies on the western site of Elginsk coal deposit, composed of four coal beds of complex structure. The reported estimates of coal ash content in the beds with respect to five components point at the need to account for such data in confirmation exploration, mine planning and actual mining. Basic means of analysis and control of overall ash content and its components are discussed.

Effects of Sediment Containing Coal Ash from the Kingston Ash Release on Embryo-Larval Development in the Fathead Minnow, Pimephales promelas (Rafinesque, 1820)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greeley Jr, Mark Stephen; Elmore, Logan R; McCracken, Kitty

2014-01-01

The largest environmental release of coal ash in U.S. history occurred in December 2008 with the failure of a retention structure at the Tennessee Valley Authority (TVA) Kingston Fossil Plant in East Tennessee. A byproduct of coal-burning power plants, coal ash is enriched in metals and metalloids such as selenium and arsenic with known toxicity to fish including embryonic and larval stages. The effects of contact exposure to sediments containing up to 78 % coal ash from the Kingston spill on the early development of fish embryos and larvae were examined in 7-day laboratory tests with the fathead minnow (Pimephalesmore » promelas). No significant effects were observed on hatching success, incidences of gross developmental abnormalities, or embryo-larval survival. Results suggest that direct exposures to sediment containing residual coal ash from the Kingston ash release may not present significant risks to fish eggs and larvae in waterways affected by the spill.« less

Trends in the Rare Earth Element Content of U.S.-Based Coal Combustion Fly Ashes.

PubMed

Taggart, Ross K; Hower, James C; Dwyer, Gary S; Hsu-Kim, Heileen

2016-06-07

Rare earth elements (REEs) are critical and strategic materials in the defense, energy, electronics, and automotive industries. The reclamation of REEs from coal combustion fly ash has been proposed as a way to supplement REE mining. However, the typical REE contents in coal fly ash, particularly in the United States, have not been comprehensively documented or compared among the major types of coal feedstocks that determine fly ash composition. The objective of this study was to characterize a broad selection of U.S. fly ashes of varied geological origin in order to rank their potential for REE recovery. The total and nitric acid-extractable REE content for more than 100 ash samples were correlated with characteristics such as the major element content and coal basin to elucidate trends in REE enrichment. Average total REE content (defined as the sum of the lanthanides, yttrium, and scandium) for ashes derived from Appalachian sources was 591 mg kg(-1) and significantly greater than in ashes from Illinois and Powder River basin coals (403 and 337 mg kg(-1), respectively). The fraction of critical REEs (Nd, Eu, Tb, Dy, Y, and Er) in the fly ashes was 34-38% of the total and considerably higher than in conventional ores (typically less than 15%). Powder River Basin ashes had the highest extractable REE content, with 70% of the total REE recovered by heated nitric acid digestion. This is likely due to the higher calcium content of Powder River Basin ashes, which enhances their solubility in nitric acid. Sc, Nd, and Dy were the major contributors to the total REE value in fly ash, based on their contents and recent market prices. Overall, this study shows that coal fly ash production could provide a substantial domestic supply of REEs, but the feasibility of recovery depends on the development of extraction technologies that could be tailored to the major mineral content and origins of the feed coal for the ash.

Exposure-Reducing Behaviors among Residents Living near a Coal Ash Storage Site

ERIC Educational Resources Information Center

Zierold, Kristina M.; Sears, Clara G.; Brock, Guy N.

2016-01-01

Coal ash, a waste product generated from burning coal for energy, is composed of highly respirable particles containing heavy metals, radioactive elements, and polycylic aromatic hydrocarbons. Coal ash is stored in landfills and surface impoundments frequently located near neighborhoods. Fugitive dust from the storage sites exposes neighborhoods,…

Fate of the naturally occurring radioactive materials during treatment of acid mine drainage with coal fly ash and aluminium hydroxide.

PubMed

Madzivire, Godfrey; Maleka, Peane P; Vadapalli, Viswanath R K; Gitari, Wilson M; Lindsay, Robert; Petrik, Leslie F

2014-01-15

Mining of coal is very extensive and coal is mainly used to produce electricity. Coal power stations generate huge amounts of coal fly ash of which a small amount is used in the construction industry. Mining exposes pyrite containing rocks to H2O and O2. This results in the oxidation of FeS2 to form H2SO4. The acidic water, often termed acid mine drainage (AMD), causes dissolution of potentially toxic elements such as, Fe, Al, Mn and naturally occurring radioactive materials such as U and Th from the associated bedrock. This results in an outflow of AMD with high concentrations of sulphate ions, Fe, Al, Mn and naturally occurring radioactive materials. Treatment of AMD with coal fly ash has shown that good quality water can be produced which is suitable for irrigation purposes. Most of the potentially toxic elements (Fe, Al, Mn, etc) and substantial amounts of sulphate ions are removed during treatment with coal fly ash. This research endeavours to establish the fate of the radioactive materials in mine water with coal fly ash containing radioactive materials. It was established that coal fly ash treatment method was capable of removing radioactive materials from mine water to within the target water quality range for drinking water standards. The alpha and beta radioactivity of the mine water was reduced by 88% and 75% respectively. The reduced radioactivity in the mine water was due to greater than 90% removal of U and Th radioactive materials from the mine water after treatment with coal fly ash as ThO2 and UO2. No radioisotopes were found to leach from the coal fly ash into the mine water. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of coal ash on growth and metal uptake by some selected ectomycorrhizal fungi in vitro

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ray, P.; Reddy, U.G.; Lapeyrie, F.

2005-07-01

Six isolates of ectomycorrhizal fungi namely, Laccaria fraterna (EM-1083), Pisolithus tinctorius (EM-1081), Pisolithus tinctorius (EM-1290), Pisolithus tinctorius (EM-1293), Scleroderma verucosurn (EM-1283), and Scleroderma cepa (EM-1233), were grown on three variants of coal ash, namely electrostatically precipitated (ESP) ash, pond ash, and bottom ash moistened with Modified Melin-Norkans (MMN) medium in vitro. The colony diameter reflected the growth of the isolates on the coal ash. Metal accumulation in the mycelia was assayed by atomic absorption spectrophotometry. Six metals, namely aluminum, cadmium, chromium, iron, lead, and nickel were selected on the basis of their abundance in coal ash and toxicity potential formore » the present work. Growth of vegetative mycelium on fly ash variants and metal accumulation data indicated that Pisolithus tinctorius (EM-1290) was the most tolerant among the isolates tested for most of the metals. Since this isolate is known to be mycorrhizal with Eucalyptus, it could be used for the reclamation of coal ash over burdened sites.« less

Apparatus and method for direct measurement of coal ash sintering and fusion properties at elevated temperatures and pressures

DOEpatents

Khan, M. Rashid

1990-01-01

A high-pressure microdilatometer is provided for measuring the sintering and fusion properties of various coal ashes under the influence of elevated pressures and temperatures in various atmospheres. Electrical resistivity measurements across a sample of coal ash provide a measurement of the onset of the sintering and fusion of the ash particulates while the contraction of the sample during sintering is measured with a linear variable displacement transducer for detecting the initiation of sintering. These measurements of sintering in coal ash at different pressures provide a mechanism by which deleterious problems due to the sintering and fusion of ash in various combustion systems can be minimized or obviated.

Development of the chemical and electrochemical coal cleaning process

NASA Astrophysics Data System (ADS)

Basilio, C. I.; Yoon, Roe-Hoan

The continuous testing of the Chemical and Electrochemical Coal Cleaning (CECC) was completed successfully using Middle Wyodak and Elkhorn No. 3 coal samples. The CECC unit was run under the optimum conditions established for these coal samples. For the Middle Wyodak coal, the ash content was reduced from 6.96 percent to as low 1.61 percent, corresponding to an ash rejection (by weight) of about 83 percent. The ash and sulfur contents of the Elkhorn No. 3 coal were reduced to as low as 1.8 percent and 0.9 percent. The average ash and sulfur rejections were calculated to be around 84 percent and 47 percent. The CECC continuous unit was used to treat -325 mesh Elkhorn No. 3 coal samples and gave ash and sulfur rejection values of as high as 77 percent and 66 percent. In these test, the clean -325 mesh coal particles were separated from the liberated mineral matter through microbubble column flotation, instead of wet-screening.

Recovery of Rare Earth Elements from Coal and Coal Byproducts via a Closed Loop Leaching Process: Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peterson, Richard; Heinrichs, Michael; Argumedo, Darwin

Objectives: Through this grant, Battelle proposes to address Area of Interest (AOI) 1 to develop a bench-scale technology to economically separate, extract, and concentrate mixed REEs from coal ash. U.S. coal and coal byproducts provide the opportunity for a domestic source of REEs. The DOE’s National Energy Technology Laboratory (NETL) has characterized various coal and coal byproducts samples and has found varying concentrations of REE ranging up to 1,000 parts per million by weight. The primary project objective is to validate the economic viability of recovering REEs from the coal byproduct coal ash using Battelle’s patented closed-loop Acid Digestion Processmore » (ADP). This will be accomplished by selecting coal sources with the potential to provide REE concentrations above 300 parts per million by weight, collecting characterization data for coal ash samples generated via three different methods, and performing a Techno-Economic Analysis (TEA) for the proposed process. The regional availability of REE-laden coal ash, the regional market for rare earth concentrates, and the system capital and operating costs for rare earth recovery using the ADP technology will be accounted for in the TEA. Limited laboratory testing will be conducted to generate the parameters needed for the design of a bench scale system for REE recovery. The ultimate project outcome will be the design for an optimized, closed loop process to economically recovery REEs such that the process may be demonstrated at the bench scale in a Phase 2 project. Project Description: The project will encompass evaluation of the ADP technology for the economic recovery of REEs from coal and coal ash. The ADP was originally designed and demonstrated for the U.S. Army to facilitate demilitarization of cast-cured munitions via acid digestion in a closed-loop process. Proof of concept testing has been conducted on a sample of Ohio-based Middle Kittanning coal and has demonstrated the feasibility of recovering REEs using the ADP technology. In AOI 1, Ohio coal sources with the potential to provide a consistent source of rare earth element concentrations above 300 parts per million will be identified. Coal sample inventories from West Virginia and Pennsylvania will also be assessed for purposes of comparison. Three methods of preparing the coal ash will be evaluated for their potential to enhance the technical feasibility and economics of REE recovery. Three sources of coal ash are targeted for evaluation of the economics of REE recovery in this project: (1) coal ash from power generation stations, to include fly ash and/or bottom ash, (2) ash generated in a lower temperature ashing process, and (3) ash residual from Battelle’s coal liquefaction process. Making use of residual ash from coal liquefaction processes directly leverages work currently being conducted by Battelle for DOE NETL in response to DE-FOA-0000981 entitled “Greenhouse Gas Emissions Reductions Research and Development Leading to Cost-Competitive Coal-to-Liquids Based Jet Fuel Production.” Using the sample characterization results and regional information regarding REE concentration, availability and cost, a TEA will be developed. The previously generated laboratory testing results for leaching and REE recovery via the ADP will be used to perform the TEA, along with common engineering assumptions for scale up of equipment and labor costs. Finally, upon validation of the economic feasibility of the process by the TEA, limited laboratory testing will be performed to support the design of a bench scale system. In a future project phase, it is envisioned that the bench scale system will be constructed and operated to prove the process on a continuous basis.« less

Progression in sulfur isotopic compositions from coal to fly ash: Examples from single-source combustion in Indiana

USGS Publications Warehouse

Yaofa, Jiang; Elswick, E.R.; Mastalerz, Maria

2008-01-01

Sulfur occurs in multiple mineral forms in coals, and its fate in coal combustion is still not well understood. The sulfur isotopic composition of coal from two coal mines in Indiana and fly ash from two power plants that use these coals were studied using geological and geochemical methods. The two coal beds are Middle Pennsylvanian in age; one seam is the low-sulfur ( 5%) Springfield Coal Member of the Petersburg Formation. Both seams have ash contents of approximately 11%. Fly-ash samples were collected at various points in the ash-collection system in the two plants. The results show notable difference in ??34S for sulfur species within and between the low-sulfur and high-sulfur coal. The ??34S values for all sulfur species are exclusively positive in the low-sulfur Danville coal, whereas the ??34S values for sulfate, pyritic, and organic sulfur are both positive and negative in the high-sulfur Springfield coal. Each coal exhibits a distinct pattern of stratigraphic variation in sulfur isotopic composition. Overall, the ??34S for sulfur species values increase up the section in the low-sulfur Danville coal, whereas they show a decrease up the vertical section in the high-sulfur Springfield coal. Based on the evolution of ??34S for sulfur species, it is suggested that there was influence of seawater on peat swamp, with two marine incursions occurring during peat accumulation of the high-sulfur Springfield coal. Therefore, bacterial sulfate reduction played a key role in converting sulfate into hydrogen sulfide, sulfide minerals, and elemental sulfur. The differences in ??34S between sulfate sulfur and pyritic sulfur is very small between individual benches of both coals, implying that some oxidation occurred during deposition or postdeposition. The ??34S values for fly ash from the high-sulfur Springfield coal (averaging 9.7???) are greatly enriched in 34S relative to those in the parent coal (averaging 2.2???). This indicates a fractionation of sulfur isotopes during high-sulfur coal combustion. By contrast, the ??34S values for fly-ash samples from the low-sulfur Danville coal average 10.2???, only slightly enriched in 34S relative to those from the parent coal (average 7.5???). The ??34S values for bulk S determined directly from the fly-ash samples show close correspondence with the ??34S values for SO4- 2 leached from the fly ash in the low-sulfur coal, suggesting that the transition from pyrite to sulfate occurred via high-temperature oxidation during coal combustion. ?? 2007 Elsevier B.V. All rights reserved.

Differences in gasification behaviors and related properties between entrained gasifier fly ash and coal char

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jing Gu; Shiyong Wu; Youqing Wu

2008-11-15

In the study, two fly ash samples from Texaco gasifiers were compared to coal char and the physical and chemical properties and reactivity of samples were investigated by scanning electron microscopy (SEM), SEM-energy-dispersive spectrometry (EDS), X-ray diffraction (XRD), N{sub 2} and CO{sub 2} adsorption method, and isothermal thermogravimetric analysis. The main results were obtained. The carbon content of gasified fly ashes exhibited 31-37%, which was less than the carbon content of 58-59% in the feed coal. The fly ashes exhibited higher Brunauer-Emmett-Teller (BET) surface area, richer meso- and micropores, more disordered carbon crystalline structure, and better CO{sub 2} gasification reactivitymore » than coal char. Ashes in fly ashes occurred to agglomerate into larger spherical grains, while those in coal char do not agglomerate. The minerals in fly ashes, especial alkali and alkaline-earth metals, had a catalytic effect on gasification reactivity of fly ash carbon. In the low-temperature range, the gasification process of fly ashes is mainly in chemical control, while in the high-temperature range, it is mainly in gas diffusion control, which was similar to coal char. In addition, the carbon in fly ashes was partially gasified and activated by water vapor and exhibited higher BET surface area and better gasification activity. Consequently, the fact that these carbons in fly ashes from entrained flow gasifiers are reclaimed and reused will be considered to be feasible. 15 refs., 7 figs., 5 tabs.« less

Predicting Water Quality Problems Associated with Coal Fly Ash Disposal Facilities Using a Trace Element Partitioning Study

NASA Astrophysics Data System (ADS)

Bhattacharyya, S.; Donahoe, R. J.; Graham, E. Y.

2006-12-01

For much of the U.S., coal-fired power plants are the most important source of electricity for domestic and industrial use. Large quantities of fly ash and other coal combustion by-products are produced every year, the majority of which is impounded in lagoons and landfills located throughout the country. Many older fly ash disposal facilities are unlined and have been closed for decades. Fly ash often contains high concentrations of toxic trace elements such as arsenic, boron, chromium, molybdenum, nickel, selenium, lead, strontium and vanadium. Trace elements present in coal fly ash are of potential concern due to their toxicity, high mobility in the environment and low drinking water MCL values. Concern about the potential release of these toxic elements into the environment due to leaching of fly ash by acid rain, groundwater or acid mine drainage has prompted the EPA to develop national standards under the subtitle D of the Resource Conservation and Recovery Act (RCRA) to regulate ash disposal in landfills and surface impoundments. An attempt is made to predict the leaching of toxic elements into the environment by studying trace element partitioning in coal fly ash. A seven step sequential chemical extraction procedure (SCEP) modified from Filgueiras et al. (2002) is used to determine the trace element partitioning in seven coal fly ash samples collected directly from electric power plants. Five fly ash samples were derived from Eastern Bituminous coal, one derived from Western Sub-bituminous coal and the other derived from Northern Lignite. The sequential chemical extraction procedure gives valuable information on the association of trace elements: 1) soluble fraction, 2) exchangeable fraction, 3) acid soluble fraction, 4) easily reducible fraction, 5) moderately reducible fraction, 6) poorly reducible fraction and 7) oxidizable organics/sulfide fraction. The trace element partitioning varies with the composition of coal fly ash which is influenced by the type of coal burned. Preliminary studies show that in some fly ash samples, significant amounts of As, B, Mo, Se, Sr and V are associated with the soluble and exchangeable fraction, and thus would be highly mobile in the environment. Lead, on the other hand, is mainly associated with the amorphous Fe and Mn oxide fractions and would be highly immobile in oxidizing conditions, but mobile in reducing conditions. Ni and Cr show different associations in different fly ash samples. In most fly ash samples, significant amounts of the trace elements are associated with more stable fractions that do not threaten the environment. The study of trace element partitioning in coal fly ash thus helps us to predict their leaching behavior under various conditions.

The environmental status of coal ash produced in Israel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Metzger, L.A.

1996-12-31

From the 6.1 million tons of coal ash produced by Israeli power stations during the 1982--95 period, 65% were utilized for cement production, 18% served to construct embankments around the Hadera coastal power station, and the remaining 17% were disposed to the sea, according to permits issued by the governmental authorities. The coal imported to Israel is typically low-sulfur, beneficiated bituminous coal, and ash produced from it is alkaline and characterized by low concentrations of trace elements. According to the results of leaching tests, the potential release of trace elements from the ash is low, thus there is only amore » minor risk of contaminating groundwater under disposal or utilization sites. However, while the annual ash production increases and is planned to reach one million tons in the year 2000, the promotion of ash employment for new applications, for example as a road base material or for shore extension projects, is still prevented by the absence of regulations fixing the environmental status of coal ash.« less

Trace and major element pollution originating from coal ash suspension and transport processes.

PubMed

Popovic, A; Djordjevic, D; Polic, P

2001-04-01

Coal ash obtained by coal combustion in the "Nikola Tesla A" power plant in Obrenovac, near Belgrade, Yugoslavia, is mixed with water of the Sava river and transported to the dump. In order to assess pollution caused by leaching of some minor and major elements during ash transport through the pipeline, two sets of samples (six samples each) were subjected to a modified sequential extraction. The first set consisted of coal ash samples taken immediately after combustion, while the second set was obtained by extraction with river water, imitating the processes that occur in the pipeline. Samples were extracted consecutively with distilled water and a 1 M solution of KCl, pH 7, and the differences in extractability were compared in order to predict potential pollution. Considering concentrations of seven trace elements as well as five major elements in extracts from a total of 12 samples, it can be concluded that lead and cadmium do not present an environmental threat during and immediately after ash transport to the dump. Portions of zinc, nickel and chromium are released during the ash transport, and arsenic and manganese are released continuously. Copper and iron do not present an environmental threat due to element leaching during and immediately after the coal ash suspension and transport. On the contrary, these elements, as well as chromium, become concentrated during coal ash transport. Adsorbed portions of calcium, magnesium and potassium are also leached during coal ash transport.

Trace elements in coal ash

USGS Publications Warehouse

Deonarine, Amrika; Kolker, Allan; Doughten, Michael W.

2015-01-01

In this fact sheet, the form, distribution, and behavior of trace elements of environmental interest in samples of coal fly ash were investigated in response to concerns about element mobility in the event of an ash spill. The study includes laboratory-based leaching experiments to examine the behavior of trace elements, such as arsenic (As) and chromium (Cr), in response to key environmental factors including redox conditions (degree of oxygenation), which are known to vary with depth within coal ash impoundments and in natural ecosystems. The experiments show that As dissolves from samples of coal fly ash into simulated freshwater under both oxic (highly oxygenated) and anoxic (poorly oxygenated) conditions, whereas dissolved Cr concentrations are very redox dependent. This U.S. Geological Survey research helps define the distribution of elements such as As in coal ash and shows that element mobility can vary considerably under different conditions expected in the environment.

Transformations of inorganic coal constituents in combustion systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Helble, J.J.; Srinivasachar, S.; Wilemski, G.

1992-11-01

The inorganic constituents or ash contained in pulverized coal significantly increase the environmental and economic costs of coal utilization. For example, ash particles produced during combustion may deposit on heat transfer surfaces, decreasing heat transfer rates and increasing maintenance costs. The minimization of particulate emissions often requires the installation of cleanup devices such as electrostatic precipitators, also adding to the expense of coal utilization. Despite these costly problems, a comprehensive assessment of the ash formation and had never been attempted. At the start of this program, it was hypothesized that ash deposition and ash particle emissions both depended upon themore » size and chemical composition of individual ash particles. Questions such as: What determines the size of individual ash particles What determines their composition Whether or not particles deposit How combustion conditions, including reactor size, affect these processes remained to be answered. In this 6-year multidisciplinary study, these issues were addressed in detail. The ambitious overall goal was the development of a comprehensive model to predict the size and chemical composition distributions of ash produced during pulverized coal combustion. Results are described.« less

National Coal Quality Inventory (NACQI)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robert Finkelman

2005-09-30

The U.S. Geological Survey (USGS) conducted the National Coal Quality Inventory (NaCQI) between 1999 and 2005 to address a need for quality information on coals that will be mined during the next 20-30 years. Collaboration between the USGS, State geological surveys, universities, coal burning utilities, and the coal mining industry plus funding support from the Electric Power Research Institute (EPRI) and the U.S. Department of Energy (DOE) permitted collection and submittal of coal samples for analysis. The chemical data (proximate and ultimate analyses; major, minor and trace element concentrations) for 729 samples of raw or prepared coal, coal associated shale,more » and coal combustion products (fly ash, hopper ash, bottom ash and gypsum) from nine coal producing States are included. In addition, the project identified a new coal reference analytical standard, to be designated CWE-1 (West Elk Mine, Gunnison County, Colorado) that is a high-volatile-B or high-volatile-A bituminous coal with low contents of ash yield and sulfur, and very low, but detectable contents of chlorine, mercury and other trace elements.« less

Retention of elemental mercury in fly ashes in different atmospheres

DOE Office of Scientific and Technical Information (OSTI.GOV)

M.A. Lopez-Anton; M. Diaz-Somoano; M.R. Martinez-Tarazona

2007-01-15

Mercury is an extremely volatile element, which is emitted from coal combustion to the environment mostly in the vapor phase. To avoid the environmental problems that the toxic species of this element may cause, control technologies for the removal of mercury are necessary. Recent research has shown that certain fly ash materials have an affinity for mercury. Moreover, it has been observed that fly ashes may catalyze the oxidation of elemental mercury and facilitate its capture. However, the exact nature of Hg-fly ash interactions is still unknown, and mercury oxidation through fly ash needs to be investigated more thoroughly. Inmore » this work, the influence of a gas atmosphere on the retention of elemental mercury on fly ashes of different characteristics was evaluated. The retention capacity was estimated comparatively in inert and two gas atmospheres containing species present in coal gasification and coal combustion. Fly ashes produced in two pulverized coal combustion (PCC) plants, produced from coals of different rank (CTA and CTSR), and a fly ash (CTP) produced in a fluidized bed combustion (FBC) plant were used as raw materials. The mercury retention capacity of these fly ashes was compared to the retention obtained in different activated carbons. Although the capture of mercury is very similar in the gasification atmosphere and N{sub 2}, it is much more efficient in a coal combustion retention, being greater in fly ashes from PCC than those from FBC plants. 22 refs., 6 figs., 3 tabs.« less

Study on the valorization routes of ashes from thermoelectric power plants working under mono-and co-combustion regimes

NASA Astrophysics Data System (ADS)

Barbosa, Rui Pedro Fernandes

The main objective of this thesis was to study new valorization routes of ashes produced in combustion and co-combustion processes. Three main valorization pathways were analyzed: (i)production of cement mortars, (ii) production of concretes, and (iii) use as chemical agents to remove contaminants from wastewaters. Firstly, the ashes produced during the mono-combustion of coal, co-combustion of coal and meat and bone meal (MBM), and mono-combustion of MBM were characterized. The aim of this study was to understand the ashes properties in extreme levels of substitution of coal by a residue with a high contamination of specific metals. The substitution of coal by MBM produced ashes with higher content of heavy metals. Secondly, the ashes coming from an industrial power plant working under mono-combustion(coal) and co-combustion conditions (coal+sewage sludge+MBM) were studied. The use of cofuels did not promote significant changes in the chemical and ecotoxicological properties of ashes. Fly ashes were successfully stabilized/solidified in cement mortar, and bottom and circulating ashes were successfully used as raw materials in concrete. The third step involved the characterization and valorization of biomass ashes resulting from the combustion of forestry residues. The highest concentrations of metals/metalloids were found in the lowest particle size fractions of ashes. Biomass ashes successfully substituted cement and natural aggregates in concretes, without compromising their mechanical, chemical, and ecotoxicological properties. Finally, the biomass ashes were tested as chemical agents to remove contaminants from wastewaters. The removal of P, mainly phosphates, and Pb from wastewaters was assayed. Biomass ashes presented a high capacity to remove phosphates. As fly ashes were more efficient in removing phosphates, they were further used to remove Pb from wastewaters. Again, they presented a high efficiency in Pb removal. New potential valorization routes for these ashes are now opened, contributing to improve their valorization rates.

Optimum reaction ratio of coal fly ash to blast furnace cement for effective removal of hydrogen sulfide.

PubMed

Asaoka, Satoshi; Okamura, Hideo; Kim, Kyunghoi; Hatanaka, Yuzuru; Nakamoto, Kenji; Hino, Kazutoshi; Oikawa, Takahito; Hayakawa, Shinjiro; Okuda, Tetsuji

2017-02-01

Reducing hydrogen sulfide concentration in eutrophic marine sediments is crucial to maintaining healthy aquatic ecosystems. Managing fly ash, 750 million tons of which is generated annually throughout the world, is another serious environmental problem. In this study, we develop an approach that addresses both these issues by mixing coal fly ash from coal-fired power plants with blast furnace cement to remediate eutrophic sediments. The purpose of this study is to optimize the mixing ratio of coal fly ash and blast furnace cement to improve the rate of hydrogen sulfide removal based on scientific evidence obtained by removal experiments and XAFS, XRD, BET, and SEM images. In the case of 10 mg-S L -1 of hydrogen sulfide, the highest removal rate of hydrogen sulfide was observed for 87 wt% of coal fly ash due to decreased competition of adsorption between sulfide and hydroxyl ions. Whereas regarding 100 mg-S L -1 , the hydrogen sulfide removal rate was the highest for 95 wt% of coal fly ash. However, for both concentrations, the removal rate obtained by 87 wt% and 95 wt% were statistically insignificant. The crushing strength of the mixture was over 1.2 N mm -2 when the coal fly ash mixing ratio was less than 95 wt%. Consequently, the mixing ratio of coal fly ash was optimized at 87 wt% in terms of achieving both high hydrogen sulfide removal rate and sufficient crushing strength. Copyright © 2016 Elsevier Ltd. All rights reserved.

Physical and Chemical Properties of Coal Bottom Ash (CBA) from Tanjung Bin Power Plant

NASA Astrophysics Data System (ADS)

Izzati Raihan Ramzi, Nurul; Shahidan, Shahiron; Zulkhairi Maarof, Mohamad; Ali, Noorwirdawati

2016-11-01

The objective of this study is to determine the physical and chemical characteristics of Coal Bottom Ash (CBA) obtained from Tanjung Bin Power Plant Station and compare them with the characteristics of natural river sand (as a replacement of fine aggregates). Bottom ash is the by-product of coal combustion during the electricity generating process. However, excess bottom ash production due to the high production of electricity in Malaysia has caused several environmental problems. Therefore, several tests have been conducted in order to determine the physical and chemical properties of bottom ash such as specific gravity, density, particle size distribution, Scanning Electron Microscopic (SEM) and X- Ray Fluorescence (XRF) in the attempt to produce sustainable material from waste. The results indicated that the natural fine aggregate and coal bottom ash have very different physical and chemical properties. Bottom ash was classified as Class C ash. The porous structure, angular and rough texture of bottom ash affected its specific gravity and particle density. From the tests, it was found that bottom ash is recommended to be used in concrete as a replacement for fine aggregates.

ACUTE PULMONARY AND SYSTEMIC EFFECTS OF INHALED COAL FLY ASH IN RATS: COMPARISON TO AMBIENT ENVIRONMENTAL PARTICLES

EPA Science Inventory

Although primary particle emissions of ash from coal-fired power plants are well controlled, coal fly ash (CFA) can still remain a significant fraction of the overall particle exposure for some plant workers and highly impacted communities. The effect of CFA on pulmonary and syst...

ULTRAFINE ASH AEROSOLS FROM COAL COMBUSTION: CHARACTERIZATION AND HEALTH EFFECTS

EPA Science Inventory

Ultrafine coal fly ash particles, defined here as those with diameters less than 0.5 micrometer, typically comprise less than 1% of the total fly ash mass. These particles are formed almost exclusively through ash vaporization, nucleation, and coagulation/condensation mechanisms,...

Optimization of hydrogen and syngas production from PKS gasification by using coal bottom ash.

PubMed

Shahbaz, Muhammad; Yusup, Suzana; Inayat, Abrar; Patrick, David Onoja; Pratama, Angga; Ammar, Muhamamd

2017-10-01

Catalytic steam gasification of palm kernel shell is investigated to optimize operating parameters for hydrogen and syngas production using TGA-MS setup. RSM is used for experimental design and evaluating the effect of temperature, particle size, CaO/biomass ratio, and coal bottom ash wt% on hydrogen and syngas. Hydrogen production appears highly sensitive to all factors, especially temperature and coal bottom ash wt%. In case of syngas, the order of parametric influence is: CaO/biomass>coal bottom ash wt%>temperature>particle size. The significant catalytic effect of coal bottom ash is due to the presence of Fe 2 O 3 , MgO, Al 2 O 3 , and CaO. A temperature of 692°C, coal bottom ash wt% of 0.07, CaO/biomass of 1.42, and particle size of 0.75mm are the optimum conditions for augmented yield of hydrogen and syngas. The production of hydrogen and syngas is 1.5% higher in the pilot scale gasifier as compared to TGA-MS setup. Copyright © 2017 Elsevier Ltd. All rights reserved.

Arsenic and selenium capture by fly ashes at low temperature

DOE Office of Scientific and Technical Information (OSTI.GOV)

M. Antonia Lopez-Anton; Mercedes Diaz-Somoano; D. Alan Spears

2006-06-15

Arsenic and selenium compounds may be emitted to the environment during coal conversion processes, although some compounds are retained in the fly ashes, in different proportions depending on the characteristics of the ashes and process conditions. The possibility of optimizing the conditions to achieve better trace element retention appears to be an attractive, economical option for reducing toxic emissions. This approach requires a good knowledge of fly ash characteristics and a thorough understanding of the capture mechanism involved in the retention. In this work the ability of two fly ashes, one produced in pulverized coal combustion and the other inmore » fluidized bed combustion, to retain arsenic and selenium compounds from the gas phase in coal combustion and coal gasification atmospheres was investigated. To explore the possible simultaneous retention of mercury, the influence of the unburned coal particle content was also evaluated. Retention capacities between 2 and 22 mg g{sup -1} were obtained under different conditions. The unburned coal particle content in the fly ash samples does not significantly modify retention capacities. 21 refs., 6 figs., 5 tabs.« less

Applicability of the mixture of bituminous coal and anthracite to conventional pulverized coal firing boiler

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takano, Shin-Ichi; Kiga, Takashi; Miyamae, Shigehiro

1994-12-31

In some future, it is expected for Japanese power stations to be hard to get a high-grade coal like a bituminous coal. We conducted therefore pilot scale tests of pulverized blends of bituminous coal and anthracite using a 1.2MWt tunnel furnace in order to evaluate the applicability of the blends of bituminous coal and anthracite to conventional pulverized coal firing boilers. One kind of bituminous coal and two kinds of anthracite, one was of low ash content and another was of high ash content, were prepared for the test. Previously to pilot scale tests, coal properties and ash properties ofmore » the blends of bituminous coal and anthracite were analyzed to estimate the characteristics of combustion, ash deposition, and so on. In the test, we investigated the combustion efficiency, NOx emission, characteristics of ignition stability and grindability changing the blend rate of anthracite. Results of our study indicated that the critical restrictions on the blending rate of anthracite were unburnt carbon in fly ash and NOx emission as for coals tested. The acceptable limitation on blending rate of anthracite was 10 and 20%, respectively for two kinds of conventional pulverized coal fired boiler. Concerning to the grindability, it became worse with increasing the blending rate of anthracite from grindability test using a roller mill, while it became better estimating from HGI.« less

Coal ash by-product reutilization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muncy, J.; Miller, B.

1997-09-01

Potomac Electric Power Company (PEPCO) has as part of its vision and value statement that, ``We are responsible stewards of environmental and corporate resources.`` With this moral imperative in mind, a project team was charged with initiating the Coal Pile Liner Project--installing a membrane liner under the existing coal storage pile at the Morgantown Generating Station. The existing coal yard facilities were constructed prior to the current environmental regulations, and it became necessary to upgrade the storage facilities to be environmentally friendly. The project team had two objectives in this project: (1) prevent coal pile leachate from entering the groundwatermore » system; (2) test the viability of using coal ash by-products as an aggregate substitute for concrete applications. Both objectives were met, and two additional benefits were achieved as well: (1) the use of coal ash by-products as a coal liner produced significant cost savings to the project directly; (2) the use of coal ash by-products reduced plant operation and maintenance expenses.« less

Long-term carcinogenicity study in Syrian golden hamster of particulate emissions from coal- and oil-fired power plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Persson, S.A.; Ahlberg, M.; Berghem, L.

1988-04-01

Male Syrian golden hamsters were given 15 weekly intratracheal instillations with suspensions of coal fly ash or oil fly ash. Controls were instilled with saline containing gelatine (0.5 g/100 mL) or to check particle effects with suspensions of hematite (Fe/sub 2/O/sub 3/). The common weekly dose was 4.5 mg/hamster. In addition, one subgroup of hamsters was treated with oil fly ash at a weekly dose of 3.0 mg/hamster and another with coal fly ash at a weekly dose of 6.0 mg/hamster. Other groups of hamsters were treated with suspensions of benzo(a)pyrene (BaP) or with suspensions on coal fly ash, oilmore » fly ash, or Fe/sub 2/O/sub 3/ coated with BaP. The mass median aerodynamic diameters of the coal and oil fly ashes were 4.4 microns and 28 microns, respectively. Hamsters treated with oil fly ash showed a higher frequency of bronchiolar-alveolar hyperplasia than hamsters in the other treatment groups. Squamous dysplasia and squamous metaplasia were most frequent in animals treated with suspensions of BaP or BaP-coated particles. The earliest appearance of a tumor, the highest incidence of tumors, and the highest incidence of malignant tumors were observed in hamsters treated with oil fly ash coated with BaP. Squamous cell carcinoma and adenosquamous carcinoma were the most frequent malignant tumors. No malignant tumors and only few benign tumors were observed in hamsters instilled with suspensions of fly ash not coated with BaP. The present study gives no indication that coal fly ash could create more serious health problems than oil fly ash.« less

Study on surface morphology and physicochemical properties of raw and activated South African coal and coal fly ash

NASA Astrophysics Data System (ADS)

Mishra, S. B.; Langwenya, S. P.; Mamba, B. B.; Balakrishnan, M.

South African coal and coal fly ash were selected as the raw materials to be used for study of their morphology and physicochemical properties and their respective activated carbons for adsorption applications. Coal and fly ash were individually steam activated at a temperature range of 550-1000 °C for 1 h in a muffle furnace using cylindrical stainless steel containers. Scanning electron micrographs revealed a change in surface morphology with more mineral matter available on the surface of the coal particles due to increased devolatilization. However, in the case of fly ash, the macerals coalesced to form agglomerates and the presence of unburnt carbon constituted pores of diameter between 50 and 100 nm. The BET surface area of coal improved significantly from 5.31 to 52.12 m 2/g whereas in case of fly ash the surface area of the raw sample which was originally 0.59 m 2/g and upon activation increased only up to 2.04 m 2/g. The chemical composition of the fly ash confirmed that silica was the major component which was approximately 60% by weight fraction. The impact of this study was to highlight the importance of using raw materials such as coal and a waste product, in the form of coal ash, in order to produce affordable activated carbon that can be used in drinking water treatment. This would therefore ensure that the quality of water supplied to communities for drinking is not contaminated especially by toxic organic compounds.

Transformations of inorganic coal constituents in combustion systems. Volume 1, sections 1--5: Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Helble, J.J.; Srinivasachar, S.; Wilemski, G.

1992-11-01

The inorganic constituents or ash contained in pulverized coal significantly increase the environmental and economic costs of coal utilization. For example, ash particles produced during combustion may deposit on heat transfer surfaces, decreasing heat transfer rates and increasing maintenance costs. The minimization of particulate emissions often requires the installation of cleanup devices such as electrostatic precipitators, also adding to the expense of coal utilization. Despite these costly problems, a comprehensive assessment of the ash formation and had never been attempted. At the start of this program, it was hypothesized that ash deposition and ash particle emissions both depended upon themore » size and chemical composition of individual ash particles. Questions such as: What determines the size of individual ash particles? What determines their composition? Whether or not particles deposit? How combustion conditions, including reactor size, affect these processes? remained to be answered. In this 6-year multidisciplinary study, these issues were addressed in detail. The ambitious overall goal was the development of a comprehensive model to predict the size and chemical composition distributions of ash produced during pulverized coal combustion. Results are described.« less

Rare earth minerals in a “no tonstein” section of the Dean (Fire Clay) coal, Knox County, Kentucky

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hower, James C.; Berti, Debora; Hochella, Michael F.

The Dean (Fire Clay) coal in Knox County, Kentucky, does not contain the megascopically-visible ash-fall tonstein present in most other sections of the coal bed. Like the Fire Clay tonstein, a low-ash portion of the coal is enriched in rare earth elements (>2400 ppm, on ash basis). In addition to kaolinite produced in the diagenesis of volcanic glass, transmission electron microscopy studies indicate the coal contains primary kaolinite, LaCeNdTh monazite, barium niobate, native gold, and FeNiCr spinels. The mineral assemblages, particularly the kaolinite-monazite association and its similarity to the tonsteins in coal to the east, demonstrate the coal was subjectmore » to the REE-enriched volcanic ash fall, apparently just at a more dilute level than at locations where the tonstein is present.« less

Rare earth minerals in a “no tonstein” section of the Dean (Fire Clay) coal, Knox County, Kentucky

DOE PAGES

Hower, James C.; Berti, Debora; Hochella, Michael F.; ...

2018-05-03

The Dean (Fire Clay) coal in Knox County, Kentucky, does not contain the megascopically-visible ash-fall tonstein present in most other sections of the coal bed. Like the Fire Clay tonstein, a low-ash portion of the coal is enriched in rare earth elements (>2400 ppm, on ash basis). In addition to kaolinite produced in the diagenesis of volcanic glass, transmission electron microscopy studies indicate the coal contains primary kaolinite, LaCeNdTh monazite, barium niobate, native gold, and FeNiCr spinels. The mineral assemblages, particularly the kaolinite-monazite association and its similarity to the tonsteins in coal to the east, demonstrate the coal was subjectmore » to the REE-enriched volcanic ash fall, apparently just at a more dilute level than at locations where the tonstein is present.« less

MEASURE OF FLY ASH RESISTIVITY USING SIMULATED FLUE GAS ENVIRONMENTS

EPA Science Inventory

The report, describing the apparatus and laboratory procedures used to determine resistivity for a number of fly ashes under a variety of test conditions, supports research to develop a technique for predicting fly ash resistivity from chemical analyses of coal and coal ash. This...

Highlights of worldwide production and utilization of coal ash -- A survey for the period 1959--1989

DOE Office of Scientific and Technical Information (OSTI.GOV)

Manz, O.E.; Stewart, B.R.

1997-09-01

In 1960, the Coal Committee for the United Nations Economic Committee for Europe requested a group of rapporteurs to undertaken work on the utilization of ash from coal fueling thermal power stations. This later became the Group of Experts on the Utilization of Ash. In 1959, out of a world production of 100 million tons of ash, only 2% was put to use, whereas in 1969, about 15% of a production of 200 million tons was used. In 1989, 562 million tons were produced, and 90.5 million tons were used. The main uses of coal ash have been in cementmore » and concrete manufacture; in road construction and as filler on construction sites; in cellular concrete; and in lightweight aggregate and brick. Worldwide, in 1989, 27.7 million tons were used in cement and concrete manufacture, 23.6 million tons in road construction and as filler on construction sites, 2.8 million tons in cellular concrete, and 6.8 million tons in lightweight aggregate and bricks. This paper presents a worldwide survey of the production and utilization of coal ash from 1959 to 1989. The data were collected from various working papers of the US Group of Experts on the utilization of Ash and from two papers by O.E. Manz on the worldwide production and utilization of coal ash.« less

How toxic is coal ash? A laboratory toxicity case study

DOE PAGES

Sherrard, Rick M.; Carriker, Neil; Greeley, Jr., Mark Stephen

2014-12-08

Under a consent agreement among the Environmental Protection Agency (EPA) and proponents both for and against stricter regulation, EPA is to issue a new coal ash disposal rule by the end of 2014. Laboratory toxicity investigations often yield conservative estimates of toxicity because many standard test species are more sensitive than resident species, thus could provide information useful to the rule-making. However, few laboratory studies of coal ash toxicity are available; most studies reported in the literature are based solely on field investigations. In this paper, we describe a broad range of toxicity studies conducted for the Tennessee Valley Authoritymore » (TVA) Kingston ash spill, results of which help provide additional perspective on the toxicity of coal ash.« less

Selection of fluxing agent for coal ash and investigation of fusion mechanism: a first-principles study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jie Li; Mei-Fang Du; Zhong-Xiao Zhang

2009-01-15

An approach based on the ab initio quantum chemical modeling (CASTEP, generalized gradient approximation (GGA), and density functional theory (DFT)) was first employed to guide the selection of the appropriate fluxing agent to reduce the coal ash melting temperature. Two kinds of typical Chinese coal ash A and B with a high-melting temperature were chosen as the investigated subjects. Result of the calculation shows that mullite mineral, which is the main component of coal ash, is easier to combine with an electron acceptor than with an electron donor. Because the cations of borax (Na{sub 2}B{sub 4}O{sub 7}10H{sub 2}O) and limestonemore » can act as electron acceptors, borax and limestone were selected as the fluxing agents in our experiment. Results of the experiment show that the melting temperatures of coal ash A and B are both decreased by borax and limestone, respectively. Moreover, borax has a better fluxing effect than limestone under the same conditions. The further numerical study on the coal ash fusing mechanism indicates that the Na{sup +} and Ca{sup 2+} cations, as acceptors, can enter into the crystal lattice of mullite mainly through O(7) and O(8) and then cause the Al(6)-O(8) and Al(5)-O(7) bonds to rupture in the (AlO{sub 6})-octahedron. From this, mullite is forced to transform to feldspar and corundum minerals that have a low binding energy. Because of the phase change of minerals in the coal ash, the coal ash melting temperature is decreased by adding borax and limestone. 27 refs., 8 figs., 3 tabs.« less

The immersion freezing behavior of ash particles from wood and brown coal burning

NASA Astrophysics Data System (ADS)

Grawe, Sarah; Augustin-Bauditz, Stefanie; Hartmann, Susan; Hellner, Lisa; Pettersson, Jan B. C.; Prager, Andrea; Stratmann, Frank; Wex, Heike

2016-11-01

It is generally known that ash particles from coal combustion can trigger ice nucleation when they interact with water vapor and/or supercooled droplets. However, data on the ice nucleation of ash particles from different sources, including both anthropogenic and natural combustion processes, are still scarce. As fossil energy sources still fuel the largest proportion of electric power production worldwide, and biomass burning contributes significantly to the global aerosol loading, further data are needed to better assess the ice nucleating efficiency of ash particles. In the framework of this study, we found that ash particles from brown coal (i.e., lignite) burning are up to 2 orders of magnitude more ice active in the immersion mode below -32 °C than those from wood burning. Fly ash from a coal-fired power plant was shown to be the most efficient at nucleating ice. Furthermore, the influence of various particle generation methods on the freezing behavior was studied. For instance, particles were generated either by dispersion of dry sample material, or by atomization of ash-water suspensions, and then led into the Leipzig Aerosol Cloud Interaction Simulator (LACIS) where the immersion freezing behavior was examined. Whereas the immersion freezing behavior of ashes from wood burning was not affected by the particle generation method, it depended on the type of particle generation for ash from brown coal. It was also found that the common practice of treating prepared suspensions in an ultrasonic bath to avoid aggregation of particles led to an enhanced ice nucleation activity. The findings of this study suggest (a) that ash from brown coal burning may influence immersion freezing in clouds close to the source and (b) that the freezing behavior of ash particles may be altered by a change in sample preparation and/or particle generation.

Particle size distribution of fly ash from co-incineration of bituminous coal with municipal solid waste

NASA Astrophysics Data System (ADS)

Cieślik, Ewelina; Konieczny, Tomasz; Bobik, Bartłomiej

2018-01-01

One of the source of air pollutants is emission from local coal-fired boiler-houses and domestic heating boilers. The consequence of incineration of municipal waste is the introduction of additional pollutants into the atmosphere, including fly ash. The aim of this work was to evaluate the particle size distribution of fly ash emitted by coal combustion and co-incineration of coal with municipal waste in a domestic 18 kW central heating boiler equipped with an automatic fuel feeder. Mixtures of bituminous coal with different types of solid waste (5, 10 and 15% of mass fraction) were used. Solid waste types consisted of: printed, colored PE caps, fragmented cable trunking, fragmented car gaskets and shredded tires from trucks. During the incineration of a given mixture of municipal waste with bituminous coal, the velocity of exhaust gas was specified, the concentration and mass flow of fly ash were determined together with the physico-chemical parameters of the exhaust gas, the samples of emitted fly ash were taken as the test material. Particle size analysis of fly ash was performed using laser particle sizer Fritch Analysette 22. The PM10 share from all fly ashes from incineration of mixtures was about 100%. Differences were noted between PM2.5 and PM1.

Testing of the 15-inch air-sparged hydrocyclone for fine coal flotation at the Homer City preparation plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, J.D.; Yi, Y.; Gopalakrishnan, S.

1993-12-31

Previous plant testing had been limited to the processing of minus 100 mesh classifier overflow (Upper Freeport Coal {approximately} 20% ash) with the 6-inch air-sparged hydrocyclone (ASH-6C) as reported at Coal Prep 92. The ASH-6C unit was found to provide separation efficiencies equivalent, or superior, to separations with the ASH-2C system. During the summer of 1992 the construction of the first 15-inch air-sparged hydrocyclone prototype was completed by the Advanced Processing Technologies, Inc. Installation at the Homer City Coal Preparation Plant was accomplished and testing began in October 1992. The ASH-15C unit can operate at a flowrate as high asmore » 1,000 gpm. Experimental results are reported with respect to capacity, combustible recovery and clean coal quality.« less

Thermogravimetric investigation on co-combustion characteristics of tobacco residue and high-ash anthracite coal.

PubMed

Li, X G; Lv, Y; Ma, B G; Jian, S W; Tan, H B

2011-10-01

The thermal behavior of high-ash anthracite coal, tobacco residue and their blends during combustion processes was investigated by means of thermogravimetric analysis (20 K min(-1), ranging from ambient temperature to 1273 K). Effects of the mixed proportion between coal and tobacco residue on the combustion process, ignition and burnout characteristics were also studied. The results indicated that the combustion of tobacco residue was controlled by the emission of volatile matter; the regions were more complex for tobacco residue (four peaks) than for coal (two peaks). Also, the blends had integrative thermal profiles that reflected both tobacco residue and coal. The incorporation of tobacco residue could improve the combustion characteristics of high-ash anthracite coal, especially the ignition and burnout characteristics comparing with the separate burning of tobacco residue and coal. It was feasible to use the co-combustion of tobacco residue and high-ash anthracite coal as fuel. Copyright © 2011 Elsevier Ltd. All rights reserved.

Mode of occurrence of arsenic in feed coal and its derivative fly ash, Black Warrior Basin, Alabama

USGS Publications Warehouse

Zielinski, R.A.; Foster, A.L.; Meeker, G.P.; Brownfield, I.K.

2007-01-01

An arsenic-rich (As = 55 ppm) bituminous feed coal from the Black Warrior Basin, Alabama and its derivative fly ash (As = 230 ppm) were selected for detailed investigation of arsenic residence and chemical forms. Analytical techniques included microbeam analysis, selective extraction, and As K-edge X-ray absorption fine-structure (XAFS) spectroscopy. Most As in the coal is contained in a generation of As-bearing pyrite (FeS2) that formed in response to epigenetic introduction of hydrothermal fluids. XAFS results indicate that approximately 50% of the As in the coal sample occurs as the oxidized As(V) species, possibly the result of incipient oxidation of coal and pyrite prior to our analysis. Combustion of pyrite and host coal produced fly ash in which 95% of As is present as As(V). Selective extraction of the fly ash with a carbonate buffer solution (pH = 10) removed 49% of the As. A different extraction with an HCl-NH2OH mixture, which targets amorphous and poorly crystalline iron oxides, dissolved 79% of the As. XAFS spectroscopy of this highly acidic (pH = 3.0) fly ash indicated that As is associated with some combination of iron oxide, oxyhydroxide, or sulfate. In contrast, a highly alkaline (pH = 12.7) fly ash from Turkey shows most As associated with a phase similar to calcium orthoarsenate (Ca3(AsO4)2). The combined XAFS results indicate that fly ash acidity, which is determined by coal composition and combustion conditions, may serve to predict arsenic speciation in fly ash.

Physical factors affecting the mutagenicity of fly ash from a coal-fired power plant.

PubMed

Fisher, G L; Chrisp, C E; Raabe, O G

1979-05-25

The two finest, most respirable coal fly ash fractions collected from the smokestack of a power plant were more mutagenic than two coarser fractions. Mutagenicity was evaluated in the histidine-requiring bacterial strains TA 1538, TA 98, and TA 100 of Salmonella typhimurium. Ash samples collected from the hoppers of an electrostatic precipitator in the plant were not mutagenic. The mutagens in coal fly ash were resistant to x-ray or ultraviolet irradiation, possibly as a result of stabilization by fly ash surfaces. All mutagenic activity is lost with heating to 350 degrees C.

INTERACTION OF PLANAR AND NONPLANAR ORGANIC CONTAMINANTS WITH COAL FLY ASH: EFFECTS OF POLAR AND NONPOLAR SOLVENT SOLUTIONS

EPA Science Inventory

Coal fly ash has several uses but much of the material is treated as waste and disposed of in various ways including land filling. Coal fly ash also has a very high sorption capacity for a variety of anthropogenic contaminants and has been used to cleanse wastewater of such poll...

Exposure-Reducing Behaviors Among Residents Living Near a Coal Ash Storage Site.

PubMed

Zierold, Kristina M; Sears, Clara G; Brock, Guy N

2016-10-01

Coal ash, a waste product generated from burning coal for energy, is composed of highly respirable particles containing heavy metals, radioactive elements, and polycylic aromatic hydrocarbons. Coal ash is stored in landfills and surface impoundments frequently located near neighborhoods. Fugitive dust from the storage sites exposes neighborhoods, affecting the health and welfare of residents. The research questions of interest were (1) are community members concerned about coal ash exposure from the storage site; (2) what, if any, behaviors do community members engage in to reduce exposure; and (3) do exposure reducing behaviors differ by level of concern about coal ash. A community-based mixed-methods approach was used. Focus groups (n = 26) were conducted in 2012, and a cross-sectional survey was administered in 2013 (n = 231). The majority of survey respondents (62%) worried "a lot" about being exposed to coal ash; however, most did not engage in exposure-reducing behaviors, such as wearing protective equipment when doing chores. Compared with respondents who worry "some, very little, or none," or responded "I don't know," respondents who worried "a lot" about being exposed to coal ash did more exposure-reducing behaviors outdoors (p < .001) and indoors (p = .01). For people living near environmental hazards, reducing exposure is a priority. Although challenging because of the chronic nature of exposure, some behaviors can be useful in reducing exposure, such as wearing a particle-specific respirator when mowing the lawn. Communities at risk for chronic exposure to environmental toxins could benefit from education about exposure-reducing behaviors. © 2015 Society for Public Health Education.

Optimizing and Characterizing Geopolymers from Ternary Blend of Philippine Coal Fly Ash, Coal Bottom Ash and Rice Hull Ash.

PubMed

Kalaw, Martin Ernesto; Culaba, Alvin; Hinode, Hirofumi; Kurniawan, Winarto; Gallardo, Susan; Promentilla, Michael Angelo

2016-07-15

Geopolymers are inorganic polymers formed from the alkaline activation of amorphous alumino-silicate materials resulting in a three-dimensional polymeric network. As a class of materials, it is seen to have the potential of replacing ordinary Portland cement (OPC), which for more than a hundred years has been the binder of choice for structural and building applications. Geopolymers have emerged as a sustainable option vis-à-vis OPC for three reasons: (1) their technical properties are comparable if not better; (2) they can be produced from industrial wastes; and (3) within reasonable constraints, their production requires less energy and emits significantly less CO₂. In the Philippines, the use of coal ash, as the alumina- and silica- rich geopolymer precursor, is being considered as one of the options for sustainable management of coal ash generation from coal-fired power plants. However, most geopolymer mixes (and the prevalent blended OPC) use only coal fly ash. The coal bottom ash, having very few applications, remains relegated to dumpsites. Rice hull ash, from biomass-fired plants, is another silica-rich geopolymer precursor material from another significantly produced waste in the country with only minimal utilization. In this study, geopolymer samples were formed from the mixture of coal ash, using both coal fly ash (CFA) and coal bottom ash (CBA), and rice hull ash (RHA). The raw materials used for the geopolymerization process were characterized using X-ray fluorescence spectroscopy (XRF) for elemental and X-ray diffraction (XRD) for mineralogical composition. The raw materials' thermal stability and loss on ignition (LOI) were determined using thermogravimetric analysis (TGA) and reactivity via dissolution tests and inductively-coupled plasma mass spectrometry (ICP) analysis. The mechanical, thermal and microstructural properties of the geopolymers formed were analyzed using compression tests, Fourier transform infra-red spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). Using a Scheffé-based mixture design, targeting applications with low thermal conductivity, light weight and moderate strength and allowing for a maximum of five percent by mass of rice hull ash in consideration of the waste utilization of all three components, it has been determined that an 85-10-5 by weight ratio of CFA-CBA-RHA activated with 80-20 by mass ratio of 12 M NaOH and sodium silicate (55% H₂O, modulus = 3) produced geopolymers with a compressive strength of 18.5 MPa, a volumetric weight of 1660 kg/m³ and a thermal conductivity of 0.457 W/m-°C at 28-day curing when pre-cured at 80 °C for 24 h. For this study, the estimates of embodied energy and CO₂ were all below 1.7 MJ/kg and 0.12 kg CO₂/kg, respectively.

In vitro effects of coal fly ashes: hydroxyl radical generation, iron release, and DNA damage and toxicity in rat lung epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

van Maanen, J.M.; Borm, P.J.; Knaapen, A

1999-12-15

The authors measured iron release, acellular generation of hydroxyl radicals, and oxidative DNA damage and cytotoxicity in rat lung epithelial (RLE) cells by different coal fly ashes (CFA) that contain both quartz and iron. Seven samples of CFA with different particle size and quartz content (up to 14.1%) were tested along with silica (alpha-quartz), ground coal, and coal mine dust (respirable) as positive control particles, and fine TiO{sub 2} (anatase) as a negative control. Five test samples were pulverized fuel ashes (PFA), two samples were coal gasification (SCG) ashes (quartz content {lt} 0.1%), and one sample was a ground coal.more » No marked differences between SCG and PFA fly ashes were observed, and toxicity did not correlate with physicochemical characteristics or effect parameters. Stable surface radicals were only detected in the reference particles silica and coal mine dust, but not in CFA. On the other hand, hydroxyl radical generation by all fly ashes was observed in the presence of hydrogen peroxide. Also a relationship between acellular hydroxyl radical generation and oxidative DNA damage in RLE cells by CFA was observed. The respirable ashes (MAT023, 38, and 41) showed an extensive level of hydroxyl radical generation in comparison to nonrespirable fly ashes and respirable references. This was related to the iron mobilization from these particles. Themechanisms by which CFA and the positive references (silica, coal mine dust) affect rat lung epithelial cells seem to be different, and the data suggest that quartz in CFA does not act the same as quartz in silica or coal mine dust. However, the results indicate an important role for size and iron release in generation and subsequent effects of reactive oxygen species caused by CFA.« less

Critical Elements in Fly Ash from the Combustion of Bituminous Coal in Major Polish Power Plants

NASA Astrophysics Data System (ADS)

Bielowicz, Barbara; Botor, Dariusz; Misiak, Jacek; Wagner, Marian

2018-03-01

The concentration of critical elements, including such REE as Fe, Co, W, Zn, Cr, Ni, V, Mn, Ti, Ag, Ga, Ta, Sr, Li, and Cu, in the so-called fly ash obtained from the 9 Polish power plants and 1 thermal power station has been determined. The obtained values, compared with the global average concentration in bituminous coal ash and sedimentary rocks (Clarke values), have shown that the enrichment of fly ash in the specified elements takes place in only a few bituminous coal processing sites in Poland. The enrichment factor (EF) is only slightly higher (the same order of magnitude) than the Clarke values. The enrichment factor in relation to the Clarke value in the Earth's crust reached values above 10 in all of the examined ashes for the following elements: Cr, Ni, V, W, and, in some ash samples, also Cu and Zn. The obtained values are low, only slightly higher than the global average concentrations in sedimentary rocks and bituminous coal ashes. The ferromagnetic grains (microspheres) found in bituminous coal fly ashes seem to be the most economically prospective in recovery of selected critical elements. The microanalysis has shown that iron cenospheres and plerospheres in fly ash contain, in addition to enamel and iron oxides (magnetite and hematite), iron spinels enriched in Co, Cr, Cu, Mn, Ni, W, and Zn.

Pilot Plant Program for the AED Advanced Coal Cleaning System. Phase II. Interim final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1980-08-01

Advanced Energy Dynamics, Inc. (AED), has developed a proprietary coal cleaning process which employs a combination of ionization and electrostatic separation to remove both sulfur and ash from dry pulverized coal. The Ohio Department of Energy sponsored the first part of a program to evaluate, develop, and demonstrate the process in a continuous-flow pilot plant. Various coals used by Ohio electric utilities were characterized and classified, and sulfur reduction, ash reduction and Btu recovery were measured. Sulfur removal in various coals ranged from 33 to 68% (on a Btu basis). Ash removal ranged from 17 to 59% (on a Btumore » basis). Ash removal of particles greater than 53 microns ranged from 46 to 88%. Btu recovery ranged from 90 to 97%. These results, especially the large percentage removal of ash particles greater than 53 microns, suggest that the AED system can contribute materially to improved boiler performance and availability. The study indicated the following potential areas for commercial utilization of the AED process: installation between the pulverizer and boiler of conventional coal-fired power utilities; reclamation of fine coal refuse; dry coal cleaning to supplement, and, if necessary, to take the place of conventional coal cleaning; upgrading coal used in: (1) coal-oil mixtures, (2) gasification and liquefaction processes designed to handle pulverized coal; and (3) blast furnaces for making steel, as a fuel supplement to the coke. Partial cleaning of coking coal blends during preheating may also prove economically attractive. Numerous other industrial processes which use pulverized coal such as the production of activated carbon and direct reduction of iron ore may also benefit from the use of AED coal cleaning.« less

Characterization of fly ashes from circulating fluidized bed combustion (CFBC) boilers cofiring coal and petroleum coke

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feihu Li; Jianping Zhai; Xiaoru Fu

2006-08-15

The chemistry, mineralogy, morphology, and particle size distribution were investigated in fly ashes from the burning of Datong (ShanXi, China) bituminous coal and the cofiring of Mideast high-sulfur petroleum coke (PC) with 30:70 (cal %) and 50:50 (cal %) blends of Datong bituminous coal in two commercial CFBC boilers. With the exception of CaO, the amounts of major oxides in the fly ashes from cofiring PC and coal were close to those of the common coal fly ashes. The PC-coal fly ashes were enriched in Ni, V, and Mo, implying these trace elements were mainly derived from PC. Ni andmore » V, along with several other elements, such as Cr, Cu, Se, Pb, U, Th, and possibly As and Cd, increased in content with a decrease in temperature of the electrostatic precipitator (ESP). The results of chemistry, mineralogy, and morphology studies suggested that the desulfurization rate of the CFBC boilers at current conditions was low, and the PC tends to coarsen the fly ash particles and increase the loss on ignition (LOI) values, making these fly ashes unsuitable for use as a cement additive or a mineral admixture in concrete. Further studies on the combustion status of the CFBC boilers are needed if we want to be able to increase the desulfurization rate and produce high-quality fly ashes for broader and full utilization. 22 refs., 4 figs., 4 tabs.« less

Co-combustion of tannery sludge in a commercial circulating fluidized bed boiler.

PubMed

Dong, Hao; Jiang, Xuguang; Lv, Guojun; Chi, Yong; Yan, Jianhua

2015-12-01

Co-combusting hazardous wastes in existing fluidized bed combustors is an alternative to hazardous waste treatment facilities, in shortage in China. Tannery sludge is a kind of hazardous waste, considered fit for co-combusting with coal in fluidized bedboilers. In this work, co-combustion tests of tannery sludge and bituminous coal were conducted in a power plant in Jiaxing, Zhejiang province. Before that, the combustion behavior of tannery sludge and bituminous were studied by thermogravimetric analysis. Tannery sludge presented higher reactivity than bituminous coal. During the co-combustion tests, the emissions of harmful gases were monitored. The results showed that the pollutant emissions met the Chinese standard except for NOx. The Concentrations of seven trace elements (As, Cr, Cd, Ni, Cu, Pb, Mn) in three exit ash flows (bottom ash in bed, fly ash in filter, and submicrometer aerosol in flue gas) were analyzed. The results of mono-combustion of bituminous coal were compared with those of co-combustion with tannery sludge. It was found that chromium enriched in fly ash. At last, the leachability of fly ash and bottom ash was analyzed. The results showed that most species were almost equal to or below the limits except for As in bottom ashes and Cr in the fly ash of co-combustion test. The concentrations of Cr in leachates of co-combustion ashes are markedly higher than that of coal mono-combustion ashes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nanominerals and nanoparticles in feed coal and bottom ash: implications for human health effects.

PubMed

Silva, Luis F O; da Boit, Kátia M

2011-03-01

Environmental and human health risk assessments of nanoparticle effects from coal and bottom ash require thorough characterisation of nanoparticles and their aggregates. In this manuscript, we expand the study of human exposure to nanosized particles from coal combustion sources (typically <100 nm in size), characterising the complex micromineralogy of these airborne combustion-derived nanomaterials. Our study focuses on bottom ash generated in the Santa Catarina power station (Brazil) which uses coal enriched in ashes, many potential elements (e.g. Cr and Ni) and pyrite. Transmission electron microscope data reveal nanoscale C deposits juxtaposed with and overgrown by slightly larger aluminosilicate (Al-Si) glassy spheres, oxides, silicates, carbonated, phosphates and sulphates. Iron oxides (mainly hematite and magnetite) are the main bottom ash products of the oxidation of pyrite, sometimes via intermediate pyrrhotite formation. The presence of iron oxide nanocrystals mixed with silicate glass particles emphasises the complexity of coal and bottom ash micromineralogy. Given the potentially bioreactive nature of such transition metal-bearing materials, there is likely to be an increased health risk associated with their inhalation.

Relating fish health and reproductive metrics to contaminant bioaccumulation at the Tennessee Valley Authority Kingston coal ash spill site.

PubMed

Pracheil, Brenda M; Marshall Adams, S; Bevelhimer, Mark S; Fortner, Allison M; Greeley, Mark S; Murphy, Cheryl A; Mathews, Teresa J; Peterson, Mark J

2016-08-01

A 4.1 million m(3) coal ash release into the Emory and Clinch rivers in December 2008 at the Tennessee Valley Authority's Kingston Fossil Plant in east Tennessee, USA, prompted a long-term, large-scale biological monitoring effort to determine if there are chronic effects of this spill on resident biota. Because of the magnitude of the ash spill and the potential for exposure to coal ash-associated contaminants [e.g., selenium (Se), arsenic (As), and mercury (Hg)] which are bioaccumulative and may present human and ecological risks, an integrative, bioindicator approach was used. Three species of fish were monitored-bluegill (Lepomis macrochirus), redear sunfish (L. microlophus), and largemouth bass (Micropterus salmoides)-at ash-affected and reference sites annually for 5 years following the spill. On the same individual fish, contaminant burdens were measured in various tissues, blood chemistry parameters as metrics of fish health, and various condition and reproduction indices. A multivariate statistical approach was then used to evaluate relationships between contaminant bioaccumulation and fish metrics to assess the chronic, sub-lethal effects of exposure to the complex mixture of coal ash-associated contaminants at and around the ash spill site. This study suggests that while fish tissue concentrations of some ash-associated contaminants are elevated at the spill site, there was no consistent evidence of compromised fish health linked with the spill. Further, although relationships between elevated fillet burdens of ash-associated contaminants and some fish metrics were found, these relationships were not indicative of exposure to coal ash or spill sites. The present study adds to the weight of evidence from prior studies suggesting that fish populations have not incurred significant biological effects from spilled ash at this site: findings that are relevant to the current national discussions on the safe disposal of coal ash waste.

Evaluation of engineering properties for the use of leached brown coal ash in soil covers.

PubMed

Mudd, Gavin M; Chakrabarti, Srijib; Kodikara, Jayantha

2007-01-31

The need to engineer cover systems for the successful rehabilitation or remediation of a wide variety of solid wastes is increasing. Some common applications include landfills, hazardous waste repositories, or mine tailings dams and waste rock/overburden dumps. The brown coal industry of the Latrobe Valley region of Victoria, Australia, produces significant quantities of coal ash and overburden annually. There are some site-specific acid mine drainage (AMD) issues associated with overburden material. This needs to be addressed both during the operational phase of a project and during rehabilitation. An innovative approach was taken to investigate the potential to use leached brown coal ash in engineered soil covers on this overburden dump. The basis for this is two-fold: first, the ash has favourable physical characteristics for use in cover systems (such as high storage capacity/porosity, moderately low permeability, and an ability to act as a capillary break layer generating minimal leachate or seepage); and second, the leachate from the ash is mildly alkaline (which can help to mitigate and reduce the risk of AMD). This paper will review the engineering issues involved in using leached brown coal ash in designing soil covers for potentially acid-forming overburden dumps. It presents the results of laboratory work investigating the technical feasibility of using leached brown coal ash in engineered solid waste cover systems.

DNA damage induced by coal dust, fly and bottom ash from coal combustion evaluated using the micronucleus test and comet assay in vitro.

PubMed

Matzenbacher, Cristina Araujo; Garcia, Ana Letícia Hilario; Dos Santos, Marcela Silva; Nicolau, Caroline Cardoso; Premoli, Suziane; Corrêa, Dione Silva; de Souza, Claudia Telles; Niekraszewicz, Liana; Dias, Johnny Ferraz; Delgado, Tânia Valéria; Kalkreuth, Wolfgang; Grivicich, Ivana; da Silva, Juliana

2017-02-15

Coal mining and combustion generating huge amounts of bottom and fly ash are major causes of environmental pollution and health hazards due to the release of polycyclic aromatic hydrocarbons (PAH) and heavy metals. The Candiota coalfield in Rio Grande do Sul, is one of the largest open-cast coal mines in Brazil. The aim of this study was to evaluate genotoxic and mutagenic effects of coal, bottom ash and fly ash samples from Candiota with the comet assay (alkaline and modified version) and micronucleus test using the lung fibroblast cell line (V79). Qualitative and quantitative analysis of PAH and inorganic elements was carried out by High Performance Liquid Chromatography (HPLC) and by Particle-Induced X-ray Emission (PIXE) techniques respectively. The samples demonstrated genotoxic and mutagenic effects. The comet assay modified using DNA-glicosilase formamidopirimidina (FPG) endonuclease showed damage related to oxidative stress mechanisms. The amount of PAHs was higher in fly ash followed by pulverized coal. The amount of inorganic elements was highest in fly ash, followed by bottom ash. It is concluded that the samples induce DNA damage by mechanisms that include oxidative stress, due to their complex composition, and that protective measures have to be taken regarding occupational and environmental hazards. Copyright © 2016 Elsevier B.V. All rights reserved.

Description and mineralogy of Tertiary volcanic ash partings and their relationship to coal seams, near Homer, Alaska

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reinink-Smith, L.M.

1985-04-01

Outcrops of Tertiary coal-bearing units in sea cliffs of the Kenai Peninsula provide an excellent study area for volcanic ash partings in coals. Twenty mid-to late-Miocene, 50-cm to 3-m thick coal seams exposed in the sea cliffs about 10 km west of Homer contain an average of 10 volcanic ash or lapilli tuff partings each. The bedding relationships of the coal with any one parting cannot be predicted, and the contacts of the partings with the coal range from very sharp to predominantly gradational. These bedding relationships provide clues about the surface on which the ashes fell and on whichmore » the coal was accumulating. For example, some ashes fell in standing water, others on irregular subaerial surfaces. The partings are in various stages of alteration to kaolinite and bentonite, and vary in thickness from a few millimeters to about 10 cm. The consistency and texture of the partings depend on the degree of alteration; the less altered partings display visible pumice fragments and euhedral feldspars, commonly within a finer grained matrix. Separate pumice fragments, excluding matrix, can also occur as partings in the coal. The more altered partings may be wet and plastic, or they may be well indurated claystones; the colors range from gray-yellow to dark brown. The indurated prints are more common in older part of the section. The coal seams may be capped by volcanic ash partings and are commonly underlain by a pencil shale of nonvolcanic origin.« less

Determination of selected elements in whole coal and in coal ash from the eight argonne premium coal samples by atomic absorption spectrometry, atomic emission spectrometry, and ion-selective electrode

USGS Publications Warehouse

Doughten, M.W.; Gillison, J.R.

1990-01-01

Methods for the determination of 24 elements in whole coal and coal ash by inductively coupled argon plasma-atomic emission spectrometry, flame, graphite furnace, and cold vapor atomic absorption spectrometry, and by ion-selective electrode are described. Coal ashes were analyzed in triplicate to determine the precision of the methods. Results of the analyses of NBS Standard Reference Materials 1633, 1633a, 1632a, and 1635 are reported. Accuracy of the methods is determined by comparison of the analysis of standard reference materials to their certified values as well as other values in the literature.

Potassic zeolites from Brazilian coal ash for use as a fertilizer in agriculture.

PubMed

Flores, Camila Gomes; Schneider, Helena; Marcilio, Nilson Romeu; Ferret, Lizete; Oliveira, João Carlos Pinto

2017-12-01

Brazilian coal has an ash content ranging from 30 to 50% by weight. Consequently, its use in coal-fired thermoelectric for power production generates a lot of waste. The construction sector is the largest consumer of coal ash, but it cannot absorb the entire amount generated. Thus, other applications for coal ash should be studied in aim to optimize the use of this industrial waste. This research had as focus to synthesize potassic zeolite from of the coal ash into on potassium fertilizer for the grown wheat plant. In this work, it was used a subbituminous coal from Mina do Leão (RS, Brazil) presenting 48.7% ash content on a dry basis. Concerning the synthesis of potassic zeolite, it was adopted the conventional method of hydrothermal treatment with potassium hydroxide. A schedule of experiments was conducted in order to define the optimum condition of zeolite synthesis that was then used an alkaline solution of 5M KOH with a reaction time of 24h at 150°C. According to this procedure, it was obtained a zeolite with a single crystalline phase, identified through X-ray diffraction as Merlinoite. Subsequently, it was performed a set of tests using potassic zeolite asa fertilizer for plants in a greenhouse. The synthesized potassic zeolite showed a good potential for its use as fertilizer in agriculture. Copyright © 2017 Elsevier Ltd. All rights reserved.

Determination of 30 elements in coal and fly ash by thermal and epithermal neutron-activation analysis

USGS Publications Warehouse

Rowe, J.J.; Steinnes, E.

1977-01-01

Thirty elements are determined in coal and fly ash by instrumental neutron-activation analysis using both thermal and epithermal irradiation. Gamma-ray spectra were recorded 7 and 20 days after the irradiations. The procedure is applicable to the routine analysis of coals and fly ash. Epithermal irradiation was found preferable for the determination of Ni, Zn, As, Se, Br, Rb, Sr, Mo, Sb, Cs, Ba, Sm, Tb, Hf, Ta, W, Th and U, whereas thermal irradiation was best for Sc, Cr, Fe, Co, La, Ce, Nd, Eu, Yb and Lu. Results for SRM 1632 (coal) and SRM 1633 (fly ash) agree with those of other investigators. ?? 1977.

Compressive strength performance of OPS lightweight aggregate concrete containing coal bottom ash as partial fine aggregate replacement

NASA Astrophysics Data System (ADS)

Muthusamy, K.; Mohamad Hafizuddin, R.; Mat Yahaya, F.; Sulaiman, M. A.; Syed Mohsin, S. M.; Tukimat, N. N.; Omar, R.; Chin, S. C.

2018-04-01

Concerns regarding the negative impact towards environment due to the increasing use of natural sand in construction industry and dumping of industrial solid wastes namely coal bottom ash (CBA) and oil palm shell (OPS) has resulted in the development of environmental friendly lightweight concrete. The present study investigates the effect of coal bottom ash as partial fine aggregate replacement towards workability and compressive strength of oil palm shell lightweight aggregate concrete (OPS LWAC). The fresh and mechanical properties of this concrete containing various percentage of coal bottom ash as partial fine aggregate replacement were investigated. The result was compared to OPS LWAC with 100 % sand as a control specimen. The concrete workability investigated by conducting slump test. All specimens were cast in form of cubes and water cured until the testing age. The compressive strength test was carried out at 7 and 28 days. The finding shows that integration of coal bottom ash at suitable proportion enhances the strength of oil palm shell lightweight aggregate concrete.

Characterization and modes of occurrence of elements in feed coal and coal combustion products from a power plant utilizing low-sulfur coal from the Powder River Basin, Wyoming

USGS Publications Warehouse

Brownfield, Michael E.; Cathcart, James D.; Affolter, Ronald H.; Brownfield, Isabelle K.; Rice, Cynthia A.; O'Connor, Joseph T.; Zielinski, Robert A.; Bullock, John H.; Hower, James C.; Meeker, Gregory P.

2005-01-01

The U.S. Geological Survey and the University of Kentucky Center for Applied Energy Research are collaborating with an Indiana utility company to determine the physical and chemical properties of feed coal and coal combustion products from a coal-fired power plant. The Indiana power plant utilizes a low-sulfur (0.23 to 0.47 weight percent S) and lowash (4.9 to 6.3 weight percent ash) subbituminous coal from the Wyodak-Anderson coal zone in the Tongue River Member of the Paleocene Fort Union Formation, Powder River Basin, Wyoming. Based on scanning electron microscope and X-ray diffraction analyses of feed coal samples, two mineral suites were identified: (1) a primary or detrital suite consisting of quartz (including beta-form grains), biotite, feldspar, and minor zircon; and (2) a secondary authigenic mineral suite containing alumino-phosphates (crandallite and gorceixite), kaolinite, carbonates (calcite and dolomite), quartz, anatase, barite, and pyrite. The primary mineral suite is interpreted, in part, to be of volcanic origin, whereas the authigenic mineral suite is interpreted, in part, to be the result of the alteration of the volcanic minerals. The mineral suites have contributed to the higher amounts of barium, calcium, magnesium, phosphorus, sodium, strontium, and titanium in the Powder River Basin feed coals in comparison to eastern coals. X-ray diffraction analysis indicates that (1) fly ash is mostly aluminate glass, perovskite, lime, gehlenite, quartz, and phosphates with minor amounts of periclase, anhydrite, hematite, and spinel group minerals; and (2) bottom ash is predominantly quartz, plagioclase (albite and anorthite), pyroxene (augite and fassaite), rhodonite, and akermanite, and spinel group minerals. Microprobe and scanning electron microscope analyses of fly ash samples revealed quartz, zircon, and monazite, euhedral laths of corundum with merrillite, hematite, dendritic spinels/ferrites, wollastonite, and periclase. The abundant calcium and magnesium mineral phases in the fly ash are attributed to the presence of carbonate, clay, and phosphate minerals in the feed coal and their alteration to new phases during combustion. The amorphous diffraction-scattering maxima or glass 'hump' appears to reflect differences in chemical composition of fly ash and bottom ash glasses. In Wyodak-Anderson fly and bottom ashes, the center point of scattering maxima is due to calcium and magnesium content, whereas the glass 'hump' of eastern fly ash reflects variation in aluminum content. The calcium- and magnesium-rich and alumino-phosphate mineral phases in the coal combustion products can be attributed to volcanic minerals deposited in peat-forming mires. Dissolution and alteration of these detrital volcanic minerals occurred either in the peat-forming stage or during coalification and diagenesis, resulting in the authigenic mineral suite. The presence of free lime (CaO) in fly ash produced from Wyodak-Anderson coal acts as a self-contained 'scrubber' for SO3, where CaO + SO3 form anhydrite either during combustion or in the upper parts of the boiler. Considering the high lime content in the fly ash and the resulting hydration reactions after its contact with water, there is little evidence that major amounts of leachable metals are mobilized in the disposal or utilization of this fly ash.

Hydrodesulfurization and hydrodenitrogenation catalysts obtained from coal mineral matter

DOEpatents

Liu, Kindtoken H. D.; Hamrin, Jr., Charles E.

1982-01-01

A hydrotreating catalyst is prepared from coal mineral matter obtained by low temperature ashing coals of relatively low bassanite content by the steps of: (a) depositing on the low temperature ash 0.25-3 grams of an iron or nickel salt in water per gram of ash and drying a resulting slurry; (b) crushing and sizing a resulting solid; and (c) heating the thus-sized solid powder in hydrogen.

Optimizing and Characterizing Geopolymers from Ternary Blend of Philippine Coal Fly Ash, Coal Bottom Ash and Rice Hull Ash

PubMed Central

Kalaw, Martin Ernesto; Culaba, Alvin; Hinode, Hirofumi; Kurniawan, Winarto; Gallardo, Susan; Promentilla, Michael Angelo

2016-01-01

Geopolymers are inorganic polymers formed from the alkaline activation of amorphous alumino-silicate materials resulting in a three-dimensional polymeric network. As a class of materials, it is seen to have the potential of replacing ordinary Portland cement (OPC), which for more than a hundred years has been the binder of choice for structural and building applications. Geopolymers have emerged as a sustainable option vis-à-vis OPC for three reasons: (1) their technical properties are comparable if not better; (2) they can be produced from industrial wastes; and (3) within reasonable constraints, their production requires less energy and emits significantly less CO2. In the Philippines, the use of coal ash, as the alumina- and silica- rich geopolymer precursor, is being considered as one of the options for sustainable management of coal ash generation from coal-fired power plants. However, most geopolymer mixes (and the prevalent blended OPC) use only coal fly ash. The coal bottom ash, having very few applications, remains relegated to dumpsites. Rice hull ash, from biomass-fired plants, is another silica-rich geopolymer precursor material from another significantly produced waste in the country with only minimal utilization. In this study, geopolymer samples were formed from the mixture of coal ash, using both coal fly ash (CFA) and coal bottom ash (CBA), and rice hull ash (RHA). The raw materials used for the geopolymerization process were characterized using X-ray fluorescence spectroscopy (XRF) for elemental and X-ray diffraction (XRD) for mineralogical composition. The raw materials’ thermal stability and loss on ignition (LOI) were determined using thermogravimetric analysis (TGA) and reactivity via dissolution tests and inductively-coupled plasma mass spectrometry (ICP) analysis. The mechanical, thermal and microstructural properties of the geopolymers formed were analyzed using compression tests, Fourier transform infra-red spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). Using a Scheffé-based mixture design, targeting applications with low thermal conductivity, light weight and moderate strength and allowing for a maximum of five percent by mass of rice hull ash in consideration of the waste utilization of all three components, it has been determined that an 85-10-5 by weight ratio of CFA-CBA-RHA activated with 80-20 by mass ratio of 12 M NaOH and sodium silicate (55% H2O, modulus = 3) produced geopolymers with a compressive strength of 18.5 MPa, a volumetric weight of 1660 kg/m3 and a thermal conductivity of 0.457 W/m-°C at 28-day curing when pre-cured at 80 °C for 24 h. For this study, the estimates of embodied energy and CO2 were all below 1.7 MJ/kg and 0.12 kg CO2/kg, respectively. PMID:28773702

Nitrogen mineralization from sludge in an alkaline, saline coal gasification ash environment.

PubMed

Mbakwe, Ikenna; De Jager, Pieter C; Annandale, John G; Matema, Taurai

2013-01-01

Rehabilitating coal gasification ash dumps by amendment with waste-activated sludge has been shown to improve the physical and chemical properties of ash and to facilitate the establishment of vegetation. However, mineralization of organic N from sludge in such an alkaline and saline medium and the effect that ash weathering has on the process are poorly understood and need to be ascertained to make decisions regarding the suitability of this rehabilitation option. This study investigated the rate and pattern of N mineralization from sludge in a coal gasification ash medium to determine the prevalent inorganic N form in the system and assess the effect of ash weathering on N mineralization. An incubation experiment was performed in which fresh ash, weathered ash, and soil were amended with the equivalent of 90 Mg ha sludge, and N mineralization was evaluated over 63 d. More N (24%) was mineralized in fresh ash than in weathered ash and soil, both of which mineralized 15% of the initial organic N in sludge. More nitrification occurred in soil, and most of the N mineralized in ash was in the form of ammonium, indicating an inhibition of nitrifying organisms in the ash medium and suggesting that, at least initially, plants used for rehabilitation of coal gasification ash dumps will take up N mostly as ammonium. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Design and fabrication of advanced materials from Illinois coal wastes. Quarterly report, 1 December 1994--28 February 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malhotra, V.M.; Wright, M.A.

1995-12-31

The main goal of this project is to develop a bench-scale procedure to design and fabricate advanced brake and structural composite materials from Illinois coal combustion residues. During the first two quarters of the project, the thrust of the work directed towards characterizing the various coal combustion residues and FGD residue, i.e., scrubber sludge. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), differential thermal analysis (DTA), and transmission-Fourier transform infrared (FTIR) were conducted on PCC fly ash (Baldwin), FBC fly ash (ADK unit l-6), FBC fly ash (S.I. coal), FBC spent bed ash (ADM, unit l-6), bottom ash, and scrubbermore » sludge (CWLP) residues to characterize their geometrical shapes, mineral phases, and thermal stability. Our spectroscopic results indicate that the scrubber sludge is mainly composed of a gypsum-like phase whose lattice structure is different from the lattice structure of conventional gypsum, and sludge does not contain hannebachite (CaSO{sub 3}.0.5H{sub 2}O) phase. Our attempts to fabricate brake frictional shoes, in the form of 1.25 inch disks, from PCC fly ash, FBC spent bed ash, scrubber sludge, coal char, iron particles, and coal tar were successful. Based on the experience gained and microscopic analyses, we have now upscaled our procedures to fabricate 2.5 inch diameter disk,- from coal combustion residues. This has been achieved. The SEM and Young`s modulus analyses of brake composites fabricated at 400 psi < Pressure < 2200 psi suggest pressure has a strong influence on the particle packing and the filling of interstices in our composites. Also, these results along with mechanical behavior of the fabricated disks lead us to believe that the combination of surface altered PCC fly ash and scrubber sludge particles, together ed ash particles are ideal for our composite materials.« less

Petrographic, mineralogical, and chemical characterization of certain Alaskan coals and washability products. Final report, July 11, 1978-October 11, 1980

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rao, P.D.; Wolff, E.N.

1981-05-01

Petrological, mineralogical and chemical characterization provides basic information needed for proper utilization of coals. Since many of these coals are likely to be beneficiated to reduce ash, the influence of coal washing on the characteristics of the washed product is important. Twenty samples of Alaskan coal seams were used for this study. The coals studied ranged in rank from lignite to high volatile A bituminous with vitrinite/ulminite reflectance ranging from 0.25 to 1.04. Fifteen raw coals were characterized for proximate and ultimate analysis reflectance rank, petrology, composition of mineral matter, major oxides and trace elements in coal ash. Washability productsmore » of three coals from Nenana, Beluga and Matanuska coal fields were used for characterization of petrology, mineral matter and ash composition. Petrological analysis of raw coals and float-sink products showed that humodetrinite was highest in top seam in a stratigraphic sequence« less

Investigation of occupational radiation exposures to NORM at an Irish peat-fired power station and potential use of peat fly ash by the construction industry.

PubMed

Organo, C; Lee, E M; Menezes, G; Finch, E C

2005-12-01

Annually, approximately 15% of Ireland's electricity requirement is provided through the combustion of 3 x 10(6) tonnes of peat. While the literature on coal-fired power generation is quite abundant, studies on the peat-fired power generation industry from a radiological point of view are scarce. A study of the largest Irish peat-fired power plant was initiated to review the potential occupational radiation exposures arising from the occurrence of naturally occurring radioactive material (NORM) at different stages of the industrial process and to investigate any radiological health consequences that may arise should peat fly ash be used as a component of building materials. Ambient gamma dose rate measurements, radon measurements, quantification of the occupational exposure from inhalation of airborne particles (personal air sampling) and gamma spectrometry analysis of peat, peat ash and effluent samples from the ash ponds were undertaken. The results indicate that the radiation dose received by any worker involved in the processing of the peat and the handling of the ash resulting from peat combustion does not exceed 150 microSv per annum. Regulatory control of the peat-fired power generation is therefore unnecessary according to the Irish legislation with regards to NORM. The potential use of peat fly ash as a by-product in the building industry was also found to have a negligible radiological impact for construction workers and for members of the public.

Leaching kinetics of As, Mo, and Se from acidic coal fly ash samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neupane, Ghanashyam; Donahoe, Rona J.; Bhattacharyya, Siddhartha

Annually, coal-fired electric power plants produce large volumes potentially hazardous coal combustion products (CCPs) including fly ash. Since majority of the coal fly ash and other CCPs deposited in dry land fills or wet lagoons, they pose risk of contamination to local environment and hydrogeology. In this study, we present results of leaching kinetics for As, Mo, and Se from three acidic fly ash samples. This study shows that the leachate concentrations of As, Mo, and Se increase over time. Three kinetics equations, pseudo-second order, Elovich, and power-function, are able to adequately describe the experimental leaching kinetics data. Experimental leachingmore » data and modeling results indicate that the rate limiting leaching of As, Mo, and Se is largely controlled by the dissolution of the fly ash particles. Furthermore, it is important to adopt effective containment/treatment schemes to avoid potential and persistent dispersion of trace elements from ash disposal facilities to surrounding environment for a long time.« less

Leaching kinetics of As, Mo, and Se from acidic coal fly ash samples

DOE PAGES

Neupane, Ghanashyam; Donahoe, Rona J.; Bhattacharyya, Siddhartha; ...

2017-07-03

Annually, coal-fired electric power plants produce large volumes potentially hazardous coal combustion products (CCPs) including fly ash. Since majority of the coal fly ash and other CCPs deposited in dry land fills or wet lagoons, they pose risk of contamination to local environment and hydrogeology. In this study, we present results of leaching kinetics for As, Mo, and Se from three acidic fly ash samples. This study shows that the leachate concentrations of As, Mo, and Se increase over time. Three kinetics equations, pseudo-second order, Elovich, and power-function, are able to adequately describe the experimental leaching kinetics data. Experimental leachingmore » data and modeling results indicate that the rate limiting leaching of As, Mo, and Se is largely controlled by the dissolution of the fly ash particles. Furthermore, it is important to adopt effective containment/treatment schemes to avoid potential and persistent dispersion of trace elements from ash disposal facilities to surrounding environment for a long time.« less

Mineralogical, Microstructural and Thermal Characterization of Coal Fly Ash Produced from Kazakhstani Power Plants

NASA Astrophysics Data System (ADS)

Tauanov, Z.; Abylgazina, L.; Spitas, C.; Itskos, G.; Inglezakis, V.

2017-09-01

Coal fly ash (CFA) is a waste by-product of coal combustion. Kazakhstan has vast coal deposits and is major consumer of coal and hence produces huge amounts of CFA annually. The government aims to recycle and effectively utilize this waste by-product. Thus, a detailed study of the physical and chemical properties of material is required as the data available in literature is either outdated or not applicable for recently produced CFA samples. The full mineralogical, microstructural and thermal characterization of three types of coal fly ash (CFA) produced in two large Kazakhstani power plants is reported in this work. The properties of CFAs were compared between samples as well as with published values.

Properties of Controlled Low Strength Material with Circulating Fluidized Bed Combustion Ash and Recycled Aggregates

PubMed Central

Weng, Tsai-Lung; Cheng, An; Chao, Sao-Jeng; Hsu, Hui-Mi

2018-01-01

This study aims to investigate the effect of adding circulating fluidized bed combustion (CFBC) ash, desulfurization slag, air-cooled blast-furnace slag and coal bottom ash to the controlled low-strength material (CLSM). Test methods include slump flow test, ball drop test, water soluble chloride ion content measurement, compressive strength and length change measurement. The results show that (1) the use of CFBC hydration ash with desulfurization slag of slump flow is the best, and the use of CFBC hydration ash with coal bottom ash and slump flow is the worst; (2) CFBC hydration ash with desulfurization slag and chloride ion content is the highest; (3) 24 h ball drop test (diameter ≤ 76 mm), and test results are 70 mm to 76 mm; (4) CFBC hydration ash with desulfurization slag and compression strength is the highest, with the coal bottom ash being the lowest; increase of CFBC hydration ash can reduce compressive strength; and (5) the water-quenched blast furnace slag and CFBC hydration ash would expand, which results in length changes of CLSM specimens. PMID:29724055

Damage cost of the Dan River coal ash spill.

PubMed

Dennis Lemly, A

2015-02-01

The recent coal ash spill on the Dan River in North Carolina, USA has caused several negative effects on the environment and the public. In this analysis, I report a monetized value for these effects after the first 6 months following the spill. The combined cost of ecological damage, recreational impacts, effects on human health and consumptive use, and esthetic value losses totals $295,485,000. Because the environmental impact and associated economic costs of riverine coal ash spills can be long-term, on the order of years or even decades, this 6-month assessment should be viewed as a short-term preview. The total cumulative damage cost from the Dan River coal ash spill could go much higher. Published by Elsevier Ltd.

Development of low-ash, planar peat swamps in an alluvial-plain setting: The no. 5 Block beds (westphalian D) of southern West Virginia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Staub, J.R.; Richards, B.K.

1993-07-01

Coals from the No. 5 Block coal beds (Westphalian D) of the central Appalachian basin are noted for their blocky, dull character and their low ash and low sulfur content. The beds are multiple benched, with rock partings separating benches. Individual benches have limited lateral extent and, where thick, are dominated by bright, high-ash coal at the base and dull, low-ash coal in the upper parts. The duller coals contain more exinite-group and inertinite-group macerals than the brighter coals. These coal beds are encased in sandstone units dominated by fining-upward sequences. The overall depositional setting is an alluvial-plain environment withmore » northwest-flowing channels spaced approximately 20 km apart. The channels were flanked by clastic swamps about 7 km wide. Low-ash peat accumulated in areas of the flood plain most distant from the channels. These peat-accumulating swamps were about 8 km across. In a few instances low-frequency flood events introduced fine siliciclastic sediment into the peat swamps, depositing a thin layer of sediment on top of the peat. This sediment layer is thicker where the underlying coal is the thickest. These thick coal areas are topographically lower than surrounding coal areas. This relationship between coal thickness, parting thickness, and topography indicates that these peat swamps were planar at the time of deposition. Individual coal benches contain abundant preserved cellular tissue (telocollinite, semifusinite, and fusinite) at most locations, suggesting that robust vegetation was widespread in the swamps and that the morphology was planar. The high concentrations of exinite-group an inertinite-group macerals in the upper parts of benches resulted from selective decomposition and oxidation of the peat in subaerial and aquatic planar-swamp environments.« less

The geochemistry and bioreactivity of fly-ash from coal-burning power stations.

PubMed

Jones, Timothy; Wlodarczyk, Anna; Koshy, Lata; Brown, Patrick; Shao, Longyi; BéruBé, Kelly

2009-07-01

Fly-ash is a byproduct of the combustion of coal in power stations for the generation of electricity. The fly-ash forms from the melting of incombustible minerals found naturally in the coal. The very high coal combustion temperatures result in the formation of microscopic glass particles from which minerals such as quartz, haematite and mullite can later recrystallize. In addition to these minerals, the glassy fly-ash contains a number of leachable metals. Mullite is a well-known material in the ceramics industry and a known respiratory hazard. Macroscopically mullite can be found in a large range of morphologies; however microscopic crystals appear to favour a fibrous habit. Fly-ash is a recognized bioreactive material in rat lung, generating hydroxyl radicals, releasing iron, and causing DNA damage. However, the mechanisms of the bioreactivity are still unclear and the relative contributions of the minerals and leachable metals to that toxicity are not well known.

Chronic exposure to coal fly ash causes minimal changes in corticosterone and testosterone concentrations in male southern toads Bufo terrestris

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ward, C.K.; Mendonca, M.T.

More than 50% of the electricity in the United States is produced by coal-burning power plants. The byproduct of coal-burning plants is coal fly ash, which contains increased concentrations of trace metals and is disposed of in collection basins. Southern toads (Bufo terrestris) frequently use these basins for reproduction. Male toads were collected in spring 2001 and 2002 from an ash basin and a reference site and divided into four groups: toads collected at the control site and maintained on (1) control substrate and food or (2) ash and contaminated food and toads collected at the ash site and maintainedmore » in (3) control or (4) ash conditions. Blood was collected periodically during 5 months to determine testosterone and corticosterone concentrations. Reference to ash toads exhibited a significant, transient increase in corticosterone at 4 weeks, but neither corticosterone nor testosterone continued to increase beyond this time. In contrast, toads caught and maintained on ash did not exhibit increased corticosterone. Testosterone in these toads appeared to be unrelated to ash exposure. This unexpected lack of a corticosterone response and no effect on testosterone suggests that toads chronically exposed to trace metals can acclimate to a polluted environment, but they may still experience subtle long-term consequences.« less

Discussion on 'characteristics of fly ashes from full-scale coal-fired power plants and their relationship to mercury adsorption' by Lu et al.

DOE Office of Scientific and Technical Information (OSTI.GOV)

James C. Hower; Bruno Valentim; Irena J. Kostova

2008-03-15

Mercury capture by coal-combustion fly ash is a function of the amount of Hg in the feed coal, the amount of carbon in the fly ash, the type of carbon in the fly ash (including variables introduced by the rank of the feed coal), and the flue gas temperature at the point of ash collection. In their discussion of fly ash and Hg adsorption, Lu et al. (Energy Fuels 2007, 21, 2112-2120) had some fundamental flaws in their techniques, which, in turn, impact the validity of analyzed parameters. First, they used mechanical sieving to segregate fly ash size fractions. Mechanicalmore » sieving does not produce representative size fractions, particularly for the finest sizes. If the study samples were not obtained correctly, the subsequent analyses of fly ash carbon and Hg cannot accurately represent the size fractions. In the analysis of carbon forms, it is not possible to accurately determine the forms with scanning electron microscopy. The complexity of the whole particles is overlooked when just examining the outer particle surface. Examination of elements such as Hg, present in very trace quantities in most fly ashes, requires careful attention to the analytical techniques. 36 refs., 3 figs., 1 tab.« less

Geoenvironmental impacts of using high carbon fly ash in structural fill applications : [research summary].

DOT National Transportation Integrated Search

2013-03-01

Coal power plants generate approximately 50% of the electricity in the : United States. As a result, large amounts of coal combustion byproducts, : especially fly ash, are produced annually. Only 40% of the fly ash : (mainly C and F-type classificati...

Development and testing of synthetic riprap constructed from coal combustion products (CCPs).

DOT National Transportation Integrated Search

2014-07-01

Even with an increase in the amount of coal combustion products (CCPs) used in concrete con-struction, soil stabilization, and other : applications, the coal power industry must dispose of a sig-nificant amount of fly ash and bottom ash. One potentia...

MERCURY CAPTURE ON COAL COMBUSTION FLY ASH. (R827649)

EPA Science Inventory

A study was performed at the Energy and Environmental Research Center (EERC) to test the hypotheses that (1) different carbon types contained in coal combustion fly ash have variable sorption capabilities relative to mercury and (2) the inorganic fraction of coal combustion fl...

Leaching behavior of coal combustion products and the environmental implication in road construction.

DOT National Transportation Integrated Search

2011-04-01

Leaching of trace elements may raise environmental concerns when using coal fly ash in road construction. US EPA is in the process : of creating the first national rule on coal ash management, including beneficial use. Meanwhile, driven by the tighte...

Effect of fuel origin on synergy during co-gasification of biomass and coal in CO2.

PubMed

Zhang, Yan; Zheng, Yan; Yang, Mingjun; Song, Yongchen

2016-01-01

The effect of fuel origin on synergy in coal/biomass blends during co-gasification has been assessed using a congruent-mass thermogravimetry analysis (TGA) method. Results revealed that synergy occurs when ash residuals are formed, followed by an almost complete gasification of biomass. Potassium species in biomass ash play a catalytic role in promoting gasification reactivity of coal char, which is a direct consequence of synergy during co-gasification. The SEM-EDS spectra provided conclusive evidence that the transfer of potassium from biomass to the surface of coal char occurs during co-pyrolysis/gasification. Biomass ash rich in silica eliminated synergy in coal/biomass blends but not to the extent of inhibiting the reaction rate of the blended chars to make it slower than that of separated ones. The best result in terms of synergy was concluded to be the combination of low-ash coal and K-rich biomass. Copyright © 2015 Elsevier Ltd. All rights reserved.

Coal Fly Ash Ceramics: Preparation, Characterization, and Use in the Hydrolysis of Sucrose

PubMed Central

dos Santos, Ricardo Pires; Martins, Jorge; Gadelha, Carlos; Cavada, Benildo; Albertini, Alessandro Victor; Arruda, Francisco; Vasconcelos, Mayron; Teixeira, Edson; Alves, Francisca; Lima Filho, José; Freire, Valder

2014-01-01

Coal ash is a byproduct of mineral coal combustion in thermal power plants. This residue is responsible for many environmental problems because it pollutes soil, water, and air. Thus, it is important to find ways to reuse it. In this study, coal fly ash, obtained from the Presidente Médici Thermal Power Plant, was utilized in the preparation of ceramic supports for the immobilization of the enzyme invertase and subsequent hydrolysis of sucrose. Coal fly ash supports were prepared at several compaction pressures (63.66–318.30 MPa) and sintered at 1200°C for 4 h. Mineralogical composition (by X-ray diffraction) and surface area were studied. The ceramic prepared with 318.30 MPa presented the highest surface area (35 m2/g) and amount of immobilized enzyme per g of support (76.6 mg/g). In assays involving sucrose inversion, it showed a high degree of hydrolysis (around 81%) even after nine reuses and 30 days' storage. Therefore, coal fly ash ceramics were demonstrated to be a promising biotechnological alternative as an immobilization support for the hydrolysis of sucrose. PMID:25110726

Preparation of Functionally Graded Materials (FGMs) Using Coal Fly Ash and NiCr-Based Alloy Powder by Spark Plasma Sintering (SPS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaneko, Gen-yo; Kitagawa, Hiroyuki; Hasezaki, Kazuhiro

2008-02-15

Functionally Graded Materials (FGMs) were prepared by spark plasma sintering (SPS) using coal fly ash and NiCr alloy powder. The coal fly ash was produced by the Misumi Coal Thermal Power Station (Chugoku Electric Power Co., Inc.), with 80 wt% nickel and 20 wt% chromium (Fukuda Metal Foil and Powder Co., Ltd.) used as source materials. The sintering temperature in the graphite die was 1000 deg. C. X-ray diffraction patterns of the sintered coal fly ash materials indicated that mullite (3Al{sub 2}O{sub 3}{center_dot}2SiO{sub 2}) and silica (SiO{sub 2}) phases were predominant. Direct joining of coal fly ash and NiCr causesmore » fracture at the interface. This is due to the mismatch in the thermal expansion coefficients (CTE). A crack in the FGM was observed between the two layers with a CTE difference of over 4.86x10{sup -6} K{sup -1}, while a crack in the FGM was difficult to detect when the CTE difference was less than 2.77x10{sup -6} K{sup -1}.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nabeel, A.; Khan, T.A.; Sharma, D.K.

The use of low-grade coal in thermal power stations is leading to environmental pollution due to the generation of large amounts of fly ash, bottom ash, and CO{sub 2} besides other pollutants. It is therefore important to clean the coal before using it in thermal power stations, steel plants, or cement industries etc. Physical beneficiation of coal results in only limited cleaning of coal. The increasing environmental pollution problems from the use of coal have led to the development of clean coal technologies. In fact, the clean use of coal requires the cleaning of coal to ultra low ash contents,more » keeping environmental norms and problems in view and the ever-growing need to increase the efficiency of coal-based power generation. Therefore this requires the adaptation of chemical cleaning techniques for cleaning the coal to obtain ultra clean coal having ultra low ash contents. Presently the reaction conditions for chemical demineralization of low-grade coal using 20% aq NaOH treatment followed by 10% H{sub 2}SO{sub 4} leaching under reflux conditions have been optimized. In order to reduce the concentration of alkali and acid used in this process of chemical demineralization of low-grade coals, stepwise, i.e., three step process of chemical demineralization of coal using 1% or 5% aq NaOH treatment followed by 1% or 5% H{sub 2}SO{sub 4} leaching has been developed, which has shown good results in demineralization of low-grade coals. In order to conserve energy, the alkali-acid leaching of coal was also carried out at room temperature, which gave good results.« less

Unmanned aerial vehicles for the assessment and monitoring of environmental contamination: An example from coal ash spills.

PubMed

Messinger, Max; Silman, Miles

2016-11-01

Unmanned aerial vehicles (UAVs) offer new opportunities to monitor pollution and provide valuable information to support remediation. Their low-cost, ease of use, and rapid deployment capability make them ideal for environmental emergency response. Here we present a UAV-based study of the third largest coal ash spill in the United States. Coal ash from coal combustion is a toxic industrial waste material present worldwide. Typically stored in settling ponds in close proximity to waterways, coal ash poses significant risk to the environment and drinking water supplies from both chronic contamination of surface and ground water and catastrophic pond failure. We sought to provide an independent estimate of the volume of coal ash and contaminated water lost during the rupture of the primary coal ash pond at the Dan River Steam Station in Eden, NC, USA and to demonstrate the feasibility of using UAVs to rapidly respond to and measure the volume of spills from ponds or containers that are open to the air. Using structure-from-motion (SfM) imagery analysis techniques, we reconstructed the 3D structure of the pond bottom after the spill, used historical imagery to estimate the pre-spill waterline, and calculated the volume of material lost. We estimated a loss of 66,245 ± 5678 m 3 of ash and contaminated water. The technique used here allows rapid response to environmental emergencies and quantification of their impacts at low cost, and these capabilities will make UAVs a central tool in environmental planning, monitoring, and disaster response. Copyright © 2016 Elsevier Ltd. All rights reserved.

Development of a standard operating procedure for analysis of ammonia concentrations in coal fly ash : [summary].

DOT National Transportation Integrated Search

2015-04-01

Fly ash produced when pulverized coal is burned in electrical generators can be used as a : concrete additive with many benefits. However, fly ash can have a high ammonia content, : which is released when used in concrete, potentially exposing worker...

Influence Of Trace Metal Distribution On Its Leachability From Coal Fly Ash

EPA Science Inventory

The risks associated with the reuse of coal fly ash in natural environmental settings in terms of their mobility and ecotoxicological significance is largely determined by: (1) the physicochemical conditions the fly ash is placed under; (2) the total leachable metal content in fl...

ASSESSING SPECIATION AND RELEASE OF HEAVY METALS FROM COAL COMBUSTION PRODUCTS

EPA Science Inventory

In this study, the speciation of heavy metals such as arsenic, selenium, lead, zinc and mercury in coal combustion products (CCPs) was evaluated using sequential extraction procedures. Coal fly ash, bottom ash and flue gas desulphurization (FGD) sludge samples were used in the ex...

Mercury capture by selected Bulgarian fly ashes: Influence of coal rank and fly ash carbon pore structure on capture efficiency

USGS Publications Warehouse

Kostova, I.J.; Hower, J.C.; Mastalerz, Maria; Vassilev, S.V.

2011-01-01

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. ?? 2010 Elsevier Ltd.

Bench-scale performance testing and economic analyses of electrostatic dry coal cleaning. Final report, October 1980-July 1983

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rich, S.R.

1987-02-01

The report gives results of preliminary performance evaluations and economic analyses of the Advanced Energy Dynamics (AED) electrostatic dry coal-cleaning process. Grab samples of coal-feed-product coals were obtained from 25 operating physical coal-cleaning (PCC) plants. These samples were analyzed for ash, sulfur, and energy content and splits of the original samples of feed run-of-mine coal were provided for bench-scale testing in an electrostatic separation apparatus. The process showed superior sulfur-removal performance at equivalent cost and energy-recovery levels. The ash-removal capability of the process was not evaluated completely: overall, ash-removal results indicated that the process did not perform as well asmore » the PCC plants.« less

Speciation of Cr and its leachability in coal by-products from spanish coal combustion plants.

PubMed

López-Antón, M Antonia; Díaz-Somoano, Mercedes; Cuesta, Aida Fuente; Riesco, Aida Rubio; Martínez-Tarazona, M Rosa

2008-06-01

This study evaluates the behaviour of total Cr and Cr (VI) during coal combustion in two Spanish power stations. The content and distribution of Cr in the feed coal and combustion wastes was determined and the Cr contents were normalized using enrichment factor indexes. The speciation of Cr in the fly ash fractions from the different hoppers of the electrostatic precipitators was established and the possibility that the Cr (VI) might lixiviate when ashes are disposed of at landfill sites was assessed. Differences in the distribution and behavior of Cr in the two power stations were observed. According to European directive 1999/31/CEE, soluble Cr(VI) in the fly ashes studied would be unlikely to pose an environmental or health risk when the ash is disposed of.

Removal of vertigo blue dyes from Batik textile wastewater by adsorption onto activated carbon and coal bottom ash

NASA Astrophysics Data System (ADS)

Kusmiyati, L., Puspita Adi; Deni, V.; Robi Indra, S.; Islamica, Dlia; Fuadi, M.

2016-04-01

Removal of vertigo blue dye from batik textile wastewater was studied by adsorptionprocess onto activated carbon (AC) and coal bottom ash (CBA).The influence of experimental conditions (pH solution, dye concentration, and contact time) were studied on the both adsorbents. At equilibrium conditions, the data were fitted to Langmuir and Freundlich adsorption models. The maximum adsorption capacity calculated from the Langmuir model for carbon active was 6.29mg/g at pH that found to be considerably higher than that obtained for coal bottom ash 3.72mg/g pH 9. From Freundlich model, the maximum adsorption capacity is less for coal bottom ash (pH 9) than that for carbon active (pH4).

Soot, organics and ultrafine ash from air- and oxy-fired coal combustion

EPA Science Inventory

This paper is concerned with determining the effects of oxy-combustion of coal on the composition of the ultrafine fly ash. To this end, a 10 W externally heated entrained flow furnace was modified to allow the combustion of pulverized coal in flames under practically relevant s...

Soot, organics, and ultrafine ash from air- and oxy-fired coal combustion

EPA Science Inventory

This paper/presentation is concerned with determining the effects of oxy-combustion of coal on the composition of the ultrafine fly ash. To this end, a 10 W externally heated entrained flow furnace was modified to allow the combustion of pulverized coal in flames under practicall...

EFFECTS OF IRON CONTENT IN COAL COMBUSTION FLY ASHES ON SPECIATION OF MERCURY

EPA Science Inventory

The paper discusses the effects of iron content in coal combustion fly ashes on speciation of mercury. (NOTE: The chemical form of mercury species in combustion flue gases is an important influence on the control of mercury emissions from coal combustion). The study focused on th...

Whole-coal versus ash basis in coal geochemistry: a mathematical approach to consistent interpretations

USGS Publications Warehouse

Geboy, Nicholas J.; Engle, Mark A.; Hower, James C.

2013-01-01

Several standard methods require coal to be ashed prior to geochemical analysis. Researchers, however, are commonly interested in the compositional nature of the whole-coal, not its ash. Coal geochemical data for any given sample can, therefore, be reported in the ash basis on which it is analyzed or the whole-coal basis to which the ash basis data are back calculated. Basic univariate (mean, variance, distribution, etc.) and bivariate (correlation coefficients, etc.) measures of the same suite of samples can be very different depending which reporting basis the researcher uses. These differences are not real, but an artifact resulting from the compositional nature of most geochemical data. The technical term for this artifact is subcompositional incoherence. Since compositional data are forced to a constant sum, such as 100% or 1,000,000 ppm, they possess curvilinear properties which make the Euclidean principles on which most statistical tests rely inappropriate, leading to erroneous results. Applying the isometric logratio (ilr) transformation to compositional data allows them to be represented in Euclidean space and evaluated using traditional tests without fear of producing mathematically inconsistent results. When applied to coal geochemical data, the issues related to differences between the two reporting bases are resolved as demonstrated in this paper using major oxide and trace metal data from the Pennsylvanian-age Pond Creek coal of eastern Kentucky, USA. Following ilr transformation, univariate statistics, such as mean and variance, still differ between the ash basis and whole-coal basis, but in predictable and calculated manners. Further, the stability between two different components, a bivariate measure, is identical, regardless of the reporting basis. The application of ilr transformations addresses both the erroneous results of Euclidean-based measurements on compositional data as well as the inconsistencies observed on coal geochemical data reported on different bases.

Mercury in coals and fly ashes from Republika and Bobov dol thermoelectric power plants

USGS Publications Warehouse

Kostova, I.; Vassileva, C.; Hower, J.; Mastalerz, Maria; Vassilev, S.; Nikolova, N.

2011-01-01

Feed coal and y ash samples were collected at Republika and Bobov Dol thermoelectric power plants (TPPs). The y ashes (FAs) were collected fromthree rows of the hot-side electrostatic precipitators (ESPs) array. Each sam- ple was wet-screened at 100, 200, 325 and 500 mesh. The coals and y ashes were characterized with regard to their petrological and chemical composition (including mercury content) and to their surface area properties. The calculated enrichment factor (EF) shows that the Hg concentrations in the bulk coal samples from Republika and Bobov Dol TPPs are 2.19 and 1.41, respectively. In some coal size fractions the EF can be up to 4 times higher than the Clarke value. The calculated EF for fly ashes shows that the Hg concentrations in the bulk samples studied are lower (between 0.03 and 0.32) than the Clarke value. The most enriched in Hg are the fly ashes from the 3rd ESP row of Republika TPP. The Hg distribution in bulk FAs taken from dierent rows of the electrostatic precipitators of both TPPs studied shows well established tendency of gradual increase in the Hg content from the 1st to the 2nd and 3rd ESP rows. The correlation between Hg content and surface area, mesopore and micropore volume of y ashes was also done in the present investigation.

Fluidized bed combustion bottom ash: A better and alternative geo-material resource for construction.

PubMed

Mandal, A K; Paramkusam, Bala Ramudu; Sinha, O P

2018-04-01

Though the majority of research on fly ash has proved its worth as a construction material, the utility of bottom ash is yet questionable due to its generation during the pulverized combustion process. The bottom ash produced during the fluidized bed combustion (FBC) process is attracting more attention due to the novelty of coal combustion technology. But, to establish its suitability as construction material, it is necessary to characterize it thoroughly with respect to the geotechnical as well as mineralogical points of view. For fulfilling these objectives, the present study mainly aims at characterizing the FBC bottom ash and its comparison with pulverized coal combustion (PCC) bottom ash, collected from the same origin of coal. Suitability of FBC bottom ash as a dike filter material in contrast to PCC bottom ash in replacing traditional filter material such as sand was also studied. The suitability criteria for utilization of both bottom ash and river sand as filter material on pond ash as a base material were evaluated, and both river sand and FBC bottom ash were found to be satisfactory. The study shows that FBC bottom ash is a better geo-material than PCC bottom ash, and it could be highly recommended as an alternative suitable filter material for constructing ash dikes in place of conventional sand.

Reburning Characteristics of Residual Carbon in Fly Ash from CFB Boilers

NASA Astrophysics Data System (ADS)

Zhang, S. H.; Luo, H. H.; Chen, H. P.; Yang, H. P.; Wang, X. H.

The content of residual carbon in fly ash of CFB boilers is a litter high especially when low-grade coal, such as lean coal, anthracite coal, gangue, etc. is in service, which greatly influences the efficiency of boilers and fly ash further disposal. Reburn of fly ash through collection, recirculation in CFB furnace or external combustor is a possibly effective strategy to decrease the carbon content, mainly depending on the residual carbon reactivity. In this work, the combustion properties of residual carbon in fly ash and corresponding original coal from large commercial CFB boilers (Kaifeng (440t/h), and Fenyi (410t/h), all in china) are comparably investigated through experiments. The residual carbon involved was firstly extracted and enriched from fly ash by means of floating elutriation to mitigate the influence of ash and minerals on the combustion behavior of residual carbon. Then, the combustion characteristic of two residual carbons and the original coal particles was analyzed with thermogravimetric analyzer (TGA, STA409C from Nestch, Germany). It was observed that the ignition temperature of the residual carbon is much higher than that of original coal sample, and the combustion reactivity of residual carbon is not only dependent on the original coal property, but also the operating conditions. The influence of oxygen content and heating rate was also studied in TGA. The O2 concentration is set as 20%, 30%, 40% and 70% respectively in O2/N2 gas mixture with the flow rate of 100ml/min. It was found that higher oxygen content is favor for decreasing ignition temperature, accelerating the combustion rate of residual carbon. And about 40% of oxygen concentration is experimentally suggested as an optimal value when oxygen-enriched combustion is put into practice for decreasing residual carbon content of fly ash in CFB boilers.

Assessment of contamination by percolation of septic tank effluent through natural and amended soils.

PubMed

Cheung, K C; Venkitachalam, T H

2004-01-01

Fly ash has been found to be a potential material for the treatment of municipal and industrial wastewater, and may be useful in the treatment of septic tank effluent. Laboratory columns (30 cm) were used to determine the sorption capacity and hydraulic properties of lagoon fly ash, loamy sand, sand, and sand amended by lagoon fly ash (30 and 60%) and red mud gypsum (20%). The removal of chemical oxygen demand (COD) was high in all column effluents (71-93%). Extent of nitrification was high in Spearwood sand, Merribrook loamy sand and 20% red mud gypsum amended Spearwood sand. However, actual removal of nitrogen (N) was high in columns containing lagoon fly ash. Unamended Spearwood sand possessed only minimal capacity for P sorption. Merribrook loamy sand and red mud gypsum amended sand affected complete P removal throughout the study period of 12 weeks. Significant P leakage occurred from lagoon fly ash amended sand columns following 6-10 weeks of operation. Neither lagoon fly ash nor red mud gypsum caused any studied heavy metal contamination including manganese (Mn), lead (Pb), zinc (Zn), cadmium (Cd) and chromium (Cr) of effluent. It can be concluded that Merribrook loamy sand is better natural soil than Spearwood sand as a filter medium. The addition of lagoon fly ash enhanced the removal of P in Spearwood sand but the efficiency was lower than with red mud gypsum amendment.

Characterization of fly ash from low-sulfur and high-sulfur coal sources: Partitioning of carbon and trace elements with particle size

USGS Publications Warehouse

Hower, J.C.; Trimble, A.S.; Eble, C.F.; Palmer, C.A.; Kolker, A.

1999-01-01

Fly ash samples were collected in November and December of 1994, from generating units at a Kentucky power station using high- and low-sulfur feed coals. The samples are part of a two-year study of the coal and coal combustion byproducts from the power station. The ashes were wet screened at 100, 200, 325, and 500 mesh (150, 75, 42, and 25 ??m, respectively). The size fractions were then dried, weighed, split for petrographic and chemical analysis, and analyzed for ash yield and carbon content. The low-sulfur "heavy side" and "light side" ashes each have a similar size distribution in the November samples. In contrast, the December fly ashes showed the trend observed in later months, the light-side ash being finer (over 20 % more ash in the -500 mesh [-25 ??m] fraction) than the heavy-side ash. Carbon tended to be concentrated in the coarse fractions in the December samples. The dominance of the -325 mesh (-42 ??m) fractions in the overall size analysis implies, though, that carbon in the fine sizes may be an important consideration in the utilization of the fly ash. Element partitioning follows several patterns. Volatile elements, such as Zn and As, are enriched in the finer sizes, particularly in fly ashes collected at cooler, light-side electrostatic precipitator (ESP) temperatures. The latter trend is a function of precipitation at the cooler-ESP temperatures and of increasing concentration with the increased surface area of the finest fraction. Mercury concentrations are higher in high-carbon fly ashes, suggesting Hg adsorption on the fly ash carbon. Ni and Cr are associated, in part, with the spinel minerals in the fly ash. Copyright ?? 1999 Taylor & Francis.

Photosynthetic pigment concentrations, gas exchange and vegetative growth for selected monocots and dicots treated with two contrasting coal fly ashes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yunusa, I.A.M.; Burchett, M.D.; Manoharan, V.

2009-07-15

There is uncertainty as to the rates of coal fly ash needed for optimum physiological processes and growth. In the current study we tested the hyothesis that photosynthetic pigments concentrations and CO{sub 2} assimilation (A) are more sensitive than dry weights in plants grown on media amended with coal fly ash. We applied the Terrestrial Plant Growth Test (Guideline 208) protocols of the Organization for Economic Cooperation and Development (OECD) to monocots (barley (Hordeum vulgare) and ryegrass (Secale cereale)) and dicots (canola (Brasica napus), radish (Raphanus sativus), field peas (Pisum sativum), and lucerne (Medicago sativa)) on media amended with flymore » ashes derived from semi-bituminous (gray ash) or lignite (red ash) coals at rates of 0, 2.5, 5.0, 10, or 20 Mg ha(-1). The red ash had higher elemental concentrations and salinity than the gray ash. Fly ash addition had no significant effect on germination by any of the six species. At moderate rates ({<=}10 Mg ha{sup -1}) both ashes increased (P < 0.05) growth rates and concentrations of chlorophylls a and b, but reduced carotenoid concentrations. Addition of either ash increased A in radish and transpiration in barley. Growth rates and final dry weights were reduced for all of the six test species when addition rates exceeded 10 Mg ha{sup -1} for gray ash and 5 Mg ha{sup -1} for red ash. We concluded that plant dry weights, rather than pigment concentrations and/or instantaneous rates of photosynthesis, are more consistent for assessing subsequent growth in plants supplied with fly ash.« less

Design and fabrication of advanced materials from Illinois coal wastes. Quarterly report, 1 March 1995--31 May 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malhotra, V.M.; Wright, M.A.

1995-12-31

The main goal of this project is to develop a bench-scale procedure to design and fabricate advanced brake and structural composite materials from Illinois coal combustion residues. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), differential thermal analysis (DTA), and transmission-Fourier transform infrared (FTIR) were conducted on PCC fly ash (Baldwin), FBC fly ash (ADM unit1-6), FBC fly ash (S.I. coal), FBC spent bed ash (ADM unit1-6), bottom ash, and scrubber sludge (CWLP) residues to characterize their geometrical shapes, mineral phases, and thermal stability. Our spectroscopic results indicate that the scrubber sludge is mainly composed of a gypsum-like phase whosemore » lattice structure is different from the lattice structure of conventional gypsum, and sludge does not contain hannebachite (CaSO{sub 3}0.5H{sub 2}O) phase. In the second and third quarters the focus of research has been on developing protocols for the formation of advanced brake composites and structural composites. Our attempts to fabricate brake frictional shoes, in the form of 1.25 inch disks, from PCC fly ash, FBC spent bed ash, scrubber sludge, coal char, iron particles, and coal tar were successful. Based on the experience gained and microscopic analyses, we have now upscaled our procedures to fabricate 2.5 inch diameter disks from coal combustion residues. The SEM and Young`s modulus analyses of brake composites fabricated at 400 psi < Pressure < 2200 psi suggest pressure has a strong influence on the particle packing and the filling of interstices in our composites.« less

Formation and use of coal combustion residues from three types of power plants burning Illinois coals

USGS Publications Warehouse

Demir, I.; Hughes, R.E.; DeMaris, P.J.

2001-01-01

Coal, ash, and limestone samples from a fluidized bed combustion (FBC) plant, a pulverized coal combustion (PC) plant, and a cyclone (CYC) plant in Illinois were analyzed to determine the combustion behavior of mineral matter, and to propose beneficial uses for the power plant ashes. Pyrite and marcasite in coal were converted during combustion to glass, hematite and magnetite. Calcite was converted to lime and anhydrite. The clay minerals were altered to mullite and glass. Quartz was partially altered to glass. Trace elements in coal were partially mobilized during combustion and, as a result, emitted into the atmosphere or adsorbed on fly ash or on hardware on the cool side of the power plants. Overall, the mobilities of 15 trace elements investigated were lower at the FBC plant than at the other plants. Only F and Mn at the FBC plant, F, Hg, and Se at the PC plant and Be, F, Hg, and Se at the CYC plant had over 50% of their concentrations mobilized. Se and Ge could be commercially recovered from some of the combustion ashes. The FBC ashes could be used as acid neutralizing agents in agriculture and waste treatment, and to produce sulfate fertilizers, gypsum wall boards, concrete, and cement. The PC and CYC fly ashes can potentially be used in the production of cement, concrete, ceramics, and zeolites. The PC and CYC bottom ashes could be used in stabilized road bases, as frits in roof shingles, and perhaps in manufacturing amber glass. ?? 2001 Elsevier Science Ltd. All rights reserved.

[Leaching of Rare Earth Elements from Coal Ashes Using Acidophilic Chemolithotrophic Microbial Communities].

PubMed

Muravyov, M I; Bulaev, A G; Melamud, V S; Kondrat'eva, T F

2015-01-01

A method for leaching rare earth elements from coal ash in the presence of elemental sulfur using communities of acidophilic chemolithotrophic microorganisms was proposed. The optimal parameters determined for rare element leaching in reactors were as follows: temperature, 45 degrees C; initial pH, 2.0; pulp density, 10%; and the coal ash to elemental sulfur ratio, 10 : 1. After ten days of leaching, 52.0, 52.6, and 59.5% of scandium, yttrium, and lanthanum, respectively, were recovered.

On-line determination of the ash content in coal using industrial, natural gamma-ray equipment

NASA Astrophysics Data System (ADS)

Alvarez, M. C.; Dopico, M. T.

1995-12-01

This work presents phases of an investigation carried out in Spain to develop industrial natural-γ equipment to determine the ash content in coals. Initially the programme was on a laboratory scale and later tests were performed in a coal washing plant on a mixture of washed products. The results obtained are very satisfactory since the equipment permits the ash content to be determined with a mean error of 1.3% and a SD of 1.

Mercury capture by native fly ash carbons in coal-fired power plants

PubMed Central

Hower, James C.; Senior, Constance L.; Suuberg, Eric M.; Hurt, Robert H.; Wilcox, Jennifer L.; Olson, Edwin S.

2013-01-01

The control of mercury in the air emissions from coal-fired power plants is an on-going challenge. The native unburned carbons in fly ash can capture varying amounts of Hg depending upon the temperature and composition of the flue gas at the air pollution control device, with Hg capture increasing with a decrease in temperature; the amount of carbon in the fly ash, with Hg capture increasing with an increase in carbon; and the form of the carbon and the consequent surface area of the carbon, with Hg capture increasing with an increase in surface area. The latter is influenced by the rank of the feed coal, with carbons derived from the combustion of low-rank coals having a greater surface area than carbons from bituminous- and anthracite-rank coals. The chemistry of the feed coal and the resulting composition of the flue gas enhances Hg capture by fly ash carbons. This is particularly evident in the correlation of feed coal Cl content to Hg oxidation to HgCl2, enhancing Hg capture. Acid gases, including HCl and H2SO4 and the combination of HCl and NO2, in the flue gas can enhance the oxidation of Hg. In this presentation, we discuss the transport of Hg through the boiler and pollution control systems, the mechanisms of Hg oxidation, and the parameters controlling Hg capture by coal-derived fly ash carbons. PMID:24223466

Investigations of ash fouling with cattle wastes as reburn fuel in a small-scale boiler burner under transient conditions.

PubMed

Oh, Hyukjin; Annamalai, Kalyan; Sweeten, John M

2008-04-01

Fouling behavior under reburn conditions was investigated with cattle wastes (termed as feedlot biomass [FB]) and coal as reburn fuels under a transient condition and short-time operation. A small-scale (30 kW or 100,000 Btu/hr) boiler burner research facility was used for the reburn experiments. The fuels considered for these experiments were natural gas (NG) for the ashless case, pure coal, pure FB, and blends of coal and FB. Two parameters that were used to characterize the ash "fouling" were (1) the overall heat-transfer coefficient (OHTC) when burning NG and solid fuels as reburn fuels, and (2) the combustible loss through ash deposited on the surfaces of heat exchanger tubes and the bottom ash in the ash port. A new methodology is presented for determining ash-fouling behavior under transient conditions. Results on the OHTCs for solid reburn fuels are compared with the OHTCs for NG. It was found that the growth of the layer of ash depositions over longer periods typically lowers OHTC, and the increased concentration of ash in gas phase promotes radiation in high-temperature zones during initial periods while decreasing the heat transfer in low-temperature zones. The ash analyses indicated that the bottom ash in the ash port contained a smaller percentage of combustibles with a higher FB percentage in the fuels, indicating better performance compared with coal because small particles in FB burn faster and the FB has higher volatile matter on a dry ash-free basis promoting more burn out.

SPECIATION OF MERCURY IN THE PRESENCE OF COAL AND WASTE COMBUSTION FLY ASHES

EPA Science Inventory

The paper gives results of a study that focused on the oxidation of elemental mercury (Hgo) in the presence of both complex, four-component, model fly ashes, and actual coal combustion fly ashes collected from a pilot plant. Steady-state oxidation of Hgo promoted by the four-com...

THE USE OF A PRB TO TREAT GROUNDWATER IMPACTED BY COAL-COMBUSTION BY-PRODUCTS

EPA Science Inventory

The burning of coal for the production of electricity generates combustion by-products such as boiler bottom ash and fly ash. These ashes have the potential to release arsenic (As), boron (B), chromium (Cr), molybdenum (Mo), selenium (Se), vanadium (V), and zinc (Zn) to the envi...

Microwave digestion for the quantification of inorganic elements in coal and coal ash using ICP-OES.

PubMed

Low, Fiona; Zhang, Lian

2012-11-15

In this paper, microwave digestion conditions have been optimised to achieve complete recoveries for the ash-forming inorganic elements in coal and coal combustion fly ash, during the analysis by inductively coupled plasma optical emission spectroscopy (ICP-OES). The elements analysed include six major (Al, Ca, Fe, K, Mg and Na) and twelve trace (As, Ba, Be, Co, Cr, Cu, Li, Mn, Ni, Pb, Sr and V). Seven reference samples have been tested, including two standard coal references, SRM1632c and SARM19, their corresponding high-temperature ashes (HTAs), and three coal fly ash references, SRM1633c, SRM2690 and BCR38. The recoveries of individual elements in these samples have been examined intensively, as a function of the amount of hydrofluoric acid (HF, 0-2.0 ml), microwave power (900 W vs. 1200 W) and sample mass (0.05 g vs. 0.1 g). As have been confirmed, the recoveries of these individual elements varied significantly with the microwave digestion condition, elemental type and sample property. For the coal references and their HTAs, the use of HF can be ruled out for most of the elements, except K associated with feldspar, Pb and V. In particular, the recovery of Pb in coal is highly sample-specific and thus unpredictable. The majority of elements in fly ash references require the use of 0.1-0.2 ml HF for a complete recovery. Al in fly ash is the only exceptional element which gave incomplete recoveries throughout, suggesting the use of a complementary technique for its quantification. As has proven to be the only element inconsequential of sample type and digestion conditions, achieving complete recoveries for all cases. On the power parameter, using a higher power such as 1200 W is critical, which has proved to be an ultimatum for the recovery of certain elements, especially in fly ash. Halving sample mass from 0.1 g to 0.05 g was also found to be insignificant. Copyright © 2012 Elsevier B.V. All rights reserved.

Atmospheric emission of mercury due to combustion of steam coal and domestic coal in China

NASA Astrophysics Data System (ADS)

Wang, Shaobin; Luo, Kunli

2017-08-01

To study the mercury emission due to the combustion of steam coal and domestic coal in China, we analyzed the mercury contents of coal, fly ash, bottom ash and sluicing water in thermal power plants, steam boilers as well as domestic coal-stoves, in Shaanxi, Shanxi, Shandong and Yunnan Provinces. This study conduct an estimate of the Hg emission rates from steam coal and domestic coal combustion based on the method of mass distribution ratio of fly ash and bottom ash. The results show that the Hg emission rate of coal combustion in thermal power plants is about 50.21% (electrostatic precipitators + wet flue gas desulfurization), and that in heating boilers is about 67.23%, and 92.28% in industrial boilers without flue gas desulphurisation equipment. Furthermore, Hg emission rate is 83.61% due to domestic coal combustion in coal-stoves. The Hg emission amount into the atmosphere from power and heat generation, industrial boilers, domestic coal-stoves and spontaneous combustion of coal gangue is roughly estimated to be 133 ± 4, 100 ± 17, 11 ± 0.1 and 47 ± 26 tons in China in 2014, respectively, and the total Hg emission amount from this paper is estimated at 292 tons. The trends of Hg emission in China from 1991 to 2014 show an accelerating growth after 2002. The proportion of mercury emission due to thermal power, heating generation and industrial energy utilization continuously increased. The atmospheric emission of mercury due to combustion of steam coal, domestic coal and coal gangue accounts nearly 50% in total anthropogenic Hg emissions in China, indicating one of the largest sources of Hg emission in China which should draw more public and scientific attention in the future.

Rare earth elements in fly ashes created during the coal burning process in certain coal-fired power plants operating in Poland - Upper Silesian Industrial Region.

PubMed

Smolka-Danielowska, Danuta

2010-11-01

The subject of the study covered volatile ashes created during hard coal burning process in ash furnaces, in power plants operating in the Upper Silesian Industrial Region, Southern Poland. Coal-fired power plants are furnished with dust extracting devices, electro precipitators, with 99-99.6% combustion gas extracting efficiency. Activity concentrations ofTh-232, Ra-226, K-40, Ac-228, U-235 and U-238 were measured with gamma-ray spectrometer. Concentrations of selected rare soil elements (La, Ce, Nd, Sm, Y, Gd, Th, U) were analysed by means of instrumental neutron activation analysis (INAA). Mineral phases of individual ash particles were identified with the use of scanning electron microscope equipped with EDS attachment. Laser granulometric analyses were executed with the use of Analyssette analyser. The activity of the investigated fly-ash samples is several times higher than that of the bituminous coal samples; in the coal, the activities are: 226Ra - 85.4 Bq kg(-1), 40 K-689 Bq kg(-1), 232Th - 100.8 Bq kg(-1), 235U-13.5 Bq kg(-1), 238U-50 Bq kg(-1) and 228Ac - 82.4 Bq kg(-1).

The chemical composition of tertiary Indian coal ash and its combustion behaviour - a statistical approach: Part 2

NASA Astrophysics Data System (ADS)

Sharma, Arpita; Saikia, Ananya; Khare, Puja; Dutta, D. K.; Baruah, B. P.

2014-08-01

In Part 1 of the present investigation, 37 representative Eocene coal samples of Meghalaya, India were analyzed and their physico-chemical characteristics and the major oxides and minerals present in ash samples were studied for assessing the genesis of these coals. Various statistical tools were also applied to study their genesis. The datasets from Part 1 used in this investigation (Part 2) show the contribution of major oxides towards ash fusion temperatures (AFTs). The regression analysis of high temperature ash (HTA) composition and initial deformation temperature (IDT) show a definite increasing or decreasing trend, which has been used to determine the predictive indices for slagging, fouling, and abrasion propensities during combustion practices. The increase or decrease of IDT is influenced by the increase of Fe2O3, Al2O3, SiO2, and CaO, respectively. Detrital-authigenic index (DAI) calculated from the ash composition and its relation with AFT indicates Sialoferric nature of these coals. The correlation analysis, Principal Component Analysis (PCA), and Hierarchical Cluster Analysis (HCA) were used to study the possible fouling, slagging, and abrasion potentials in boilers during the coal combustion processes. A positive relationship between slagging and heating values of the coal has been found in this study.

Composition and quality of coals in the Huaibei Coalfield, Anhui, China

USGS Publications Warehouse

Zheng, Lingyun; Liu, Gaisheng; Wang, L.; Chou, C.-L.

2008-01-01

The Huaibei Coalfield, Anhui Province, China, is one of the largest coalfields in China. The coals of Permian age are used mainly for power generation. Coal compositions and 47 trace elements of the No. 10 Coal of the Shanxi Formation, the No. 7, 5, and 4 Coals of the Lower Shihezi Formation, and the No. 3 Coal of the Upper Shihezi Formation from the Huaibei Coalfield were studied. The results indicate that the Huaibei coals have low ash, moisture, and sulfur contents, but high volatile matter and calorific value. The ash yield increases stratigraphically upwards, but the volatile matter and total sulfur contents show a slight decrease from the lower to upper seams. Magmatic intrusion into the No. 5 Coal resulted in high ash, volatile matter, and calorific value, but low moisture value in the coal. Among the studied 47 trace elements, Ba, Co, Cr, Cu, Hg, Mo, Ni, Pb, Sb, Th, U, V, and Zn are of environmental concerns. Four elements Hg, Mo, Zn, and Sb are clearly enriched in the coals as compared with the upper continental crust. ?? 2007 Elsevier B.V. All rights reserved.

Removal of radium from acidic solutions containing same by adsorption on coal fly ash

DOEpatents

Scheitlin, Frank M.

1984-01-01

The invention is a process for the removal of radium from acidic aqueous solutions. In one aspect, the invention is a process for removing radium from an inorganic-acid solution. The process comprises contacting the solution with coal fly ash to effect adsorption of the radium on the ash. The radium-containing ash then is separated from the solution. The process is simple, comparatively inexpensive, and efficient. High radium-distribution coefficients are obtained even at room temperature. Coal fly ash is an inexpensive, acid-resistant, high-surface-area material which is available in large quantities throughout the United States. The invention is applicable, for example, to the recovery of .sup.226 Ra from nitric acid solutions which have been used to leach radium from uranium-mill tailings.

Environmentally critical elements in channel and cleaned samples of Illinois coals

USGS Publications Warehouse

Demir, I.; Ruch, R.R.; Damberger, H.H.; Harvey, R.D.; Steele, J.D.; Ho, K.K.

1998-01-01

Sixteen trace and minor elements that occur in coal are listed among 189 substances identified as 'hazardous air pollutants' (HAPs) in the US Clean Air Act Amendments of 1990. We investigated the occurrence and cleanability of the 16 HAPs in Illinois coals, as a contribution to the discussion about the potential effect of pending environmental regulations on the future use of these coals in power generation. The average ash content of the samples of conventionally cleaned as-shipped coals is about 20% lower than that of standard channel samples. Conventional cleaning reduces the average concentrations of As, Cd, Co, Hg, Mn, Ni, Pb, Sb and Th in the as-shipped coals by more than 20% relative to channel samples. Thus, basing assessments of health risks from emissions of HAPs during coal combustion on channel samples without appropriate adjustment would overestimate the risk. Additional cleaning by froth-flotation reduces the ash content of finely-ground as-shipped coals by as much as 76% at an 80% combustibles recovery. Although the average froth-flotation cleanability for the majority of HAPs is less than that for ash, the cleanabilities in some individual cases approaches, or even exceeds, the cleanability for ash, depending on the modes of occurrences of the elements. ?? 1997 Elsevier Science Ltd.

Investigation of mineral transformations and ash deposition during staged combustion. Quarterly technical progress report, April 1, 1997--June 30, 1997

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harb, J.N.

This report describes work performed in the fifteenth quarter of a fundamental study to examine the effect of staged combustion on ash formation and deposition. Efforts this quarter included addition of a new cyclone for improved particle sampling and modification of the existing sampling probe. Particulate samples were collected under a variety of experimental conditions for both coals under investigation. Deposits formed from the Black Thunder coal were also collected. Particle size and composition from the Pittsburgh No. 8 ash samples support previously reported results. In addition, the authors ability to distinguish char/ash associations has been refined and applied tomore » a variety of ash samples from this coal. The results show a clear difference between the behavior of included and excluded pyrite, and provide insight into the extent of pyrite oxidation. Ash samples from the Black Thunder coal have also been collected and analyzed. Results indicate a significant difference in the particle size of {open_quotes}unclassifiable{close_quotes} particles for ash formed during staged combustion. A difference in composition also appears to be present and is currently under investigation. Finally, deposits were collected under staged conditions for the Black Thunder coal. Specifically, two deposits were formed under similar conditions and allowed to mature under either reducing or oxidizing conditions in natural gas. Differences between the samples due to curing were noted. In addition, both deposits showed skeletal ash structures which resulted from in-situ burnout of the char after deposition.« less

New cleaning technologies advance coal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Onursal, B.

1984-05-01

Alternative options are discussed for reducing sulfur dioxide emissions from coal burning utility and industrial sources. Test results indicate that it may be most advantageous to use the AED Process after coal preparation or on coals that do not need much ash removal. However, the developer claims that research efforts after 1981 have led to process improvements for producing clean coals containing 1.5% to 3% ash. This paper describes the test facility where a full-scale test of the AED Process is underway.

Market assessment of PFBC ash use

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bland, A. E.; Brown, T. H., Western Research Institute

1998-01-01

Pressurized fluidized bed combustion (PFBC) of coal is undergoing demonstration in the United States, as well as throughout the world. American Electric Power`s (AEP`s) bubbling PFBC 70 MWe Tidd demonstration program in Ohio and pilot-scale development at Foster Wheeler Energia Oy 10 MWth circulating PFBC at Karhula, Finland, have demonstrated the advantages of PFBC technology. Further technology development in the US is planned with the deployment of the technology at the MacIntosh Clean Coal project in Lakeland, Florida. Development of uses for solid wastes from PFBC coal-fired power systems is being actively pursued as part of the demonstration of PFBCmore » technologies. Ashes collected from Foster Wheeler Energia Oy pilot circulating PFBC tests in Karhula, Finland, operating on (1) low sulfur subbituminous and (2) high sulfur bituminous coal; and ash from the AEP`s high-sulfur bituminous coal-fired bubbling PFBC in Brilliant, Ohio, were evaluated in laboratory and pilot-scale ash use testing at Western Research Institute (WRI).« less

Combustion characteristics and design of hot water boiler

NASA Astrophysics Data System (ADS)

Liu, Xuemin; Yang, Dinghua; Lu, Junfu; Guan, Jian; Qi, Guoli

2017-03-01

In order to understand the combustion characteristics of biomass, a detailed comparison with coal was made. There are many differences between biomass and coal in combustion characteristics. The burning rate of biomass is much higher than coal. The burning rate of biomass char is also higher than coal char. During biomass combustion, HCl, SO2 and NO x emissions mainly concentrate in volatile combustion stage, while CO2 emission mainly concentrates in char combustion stage. The slagging tendency of biomass ash is severer than coal ash and the adhesive force of biomass ash is higher. However, the wearing tendency of biomass ash is minor. Aiming at the particularity of biomass fuels, this paper briefly introduces the design of biomass hot water boilers. On this basis, a 2.8 MW biomass hot water boiler was developed and tested under the loads of 1.7 MW and 2.8MW. The running results show that the carbon content of bottom slag significantly decreases as the load increases. The boiler efficiency is higher than 85% under both loads.

Characterisation of coal washery effluent and optimisation of coagulation behaviour of Moringa oleifera seed as a coagulant.

PubMed

Kapse, Gaurav; Patoliya, Pruthvi; Samadder, S R

2017-03-01

The huge quantity of effluent generated in coal washing processes contains large amount of suspended and dissolved solids, clay minerals, coal fines and other impurities associated with raw coal. The present system of recirculation of the effluent is found to be ineffective in removing colloidal fines, which is the major part of the impurities present in washery effluent. Hence, there is a need for the assessment of a better technique for an efficient removal of these impurities. This study deals with detailed characterisation of coal washery effluent and fine particles present in it. For efficient removal of impurities, the suitability of biocoag-flocculation process using Moringa oleifera seed biomass as a natural coagulant was examined. Various doses of M. oleifera ranging from 0.2 to 3 mL/L were used in order to determine the optimal conditions. The impact of the variations in pH of the effluent (2-10), contact time (5-30 min), settlement time (5-50 min), temperature (10-50 °C) and the effluent dilution (1:0-1:5) was also assessed to optimise the treatment process. Post treatment analysis was carried out for determination of the different parameters such as pH, conductivity, turbidity, solids and settling velocity. Excellent reduction in turbidity (97.42%) and suspended solids (97.78%) was observed at an optimum dose of M. oleifera seed coagulant of 0.8 mL/L with an optimum contact time of 15 and at 20 min of settling time. In comparison with very few past studies of M. oleifera in the treatment of coal washery effluent with high dose and inadequate removal, this study stands to be a major highlight with low dose and high removal of the impurities. M. oleifera coagulant is considered to be an environment-friendly material, therefore, its application is recommended for simple and efficient treatment of coal washery effluent.

Identification of organically associated trace elements in wood and coal by inductively coupled plasma mass spectrometry.

PubMed

Richaud, R; Lazaro, M J; Lachas, H; Miller, B B; Herod, A A; Dugwell, D R; Kandiyoti, R

2000-01-01

1-Methyl-2-pyrrolidinone (NMP) was used to extract samples of wood (forest residue) and coal; the extracts were analysed by inductively coupled plasma mass spectrometry (ICP-MS) using two different sample preparation methods, in order to identify trace elements associated with the organic part of the samples. A sample of fly ash was similarly extracted and analysed in order to assess the behaviour of the mineral matter contained within the wood and coal samples. 32% of the biomass was extracted at the higher temperature and 12% at room temperature while only 12% of the coal was extracted at the higher temperature and 3% at room temperature. Less than 2% of the ash dissolved at the higher temperature. Size exclusion chromatograms of the extracts indicated the presence of significant amounts of large molecular mass materials (>1000 mu) in the biomass and coal extracts but not in the ash extract. Trace element analyses were carried out using ICP-MS on the acid digests prepared by 'wet ashing' and microwave extraction. Sixteen elements (As, Ba, Be, Cd, Co, Cr, Cu, Ga, Mn, Mo, Ni, Pb, Sb, Se, V and Zn) were quantified, in the samples before extraction, in the extracts and in the residues. Concentrations of trace elements in the original biomass sample were lower than in the coal sample while the concentrations in the ash sample were the highest. The major trace elements in the NMP extracts were Ba, Cu, Mn and Zn from the forest residue; Ba, Cu, Mn, Pb and Zn from the coal; Cu and Zn from the ash. These elements are believed to be associated with the organic extracts from the forest residue and coal, and also from the ash. Be and Sb were not quantified in the extracts because they were present at too low concentrations; up to 40% of Mn was extracted from the biomass sample at 202 degrees C, while Se was totally extracted from the ash sample. For the forest residue, approximately 7% (at room temperature) and 45% (at 202 degrees C) of the total trace elements studied were in the extract; for the coal, approximately 8% (at room temperature) and 23% (at 202 degrees C) were in the extract. For the ash, only 1.4% of the trace elements were extracted at 202 degrees C, comprising 25% of Cd but less than 1% of Pb. Copyright 2000 John Wiley & Sons, Ltd.

Coal Combustion Residual Beneficial Use Evaluation: Fly Ash Concrete and FGD Gypsum Wallboard

EPA Pesticide Factsheets

This page contains documents related to the evaluation of coal combustion residual beneficial use of fly ash concrete and FGD gypsum wallboard including the evaluation itself and the accompanying appendices

Investigations of ash fouling with cattle wastes as reburn fuel in a small-scale boiler burner under transient conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hyukjin Oh; Kalyan Annamalai; John M. Sweeten

2008-04-15

Fouling behavior under reburn conditions was investigated with cattle wastes (termed as feedlot biomass, FB) and coal as reburn fuels under a transient condition and short-time operation. A small-scale (30 kW or 100,000 Btu/hr) boiler burner research facility was used for the reburn experiments. The fuels considered for these experiments were natural gas (NG) for the ashless case, pure coal, pure FB, and blends of coal and FB. Two parameters that were used to characterize the ash 'fouling' were (1) the overall heat-transfer coefficient (OHTC) when burning NG and solid fuels as reburn fuels, and (2) the combustible loss throughmore » ash deposited on the surfaces of heat exchanger tubes and the bottom ash in the ash port. A new methodology is presented for determining ash fouling behavior under transient conditions. Results on the OHTCs for solid reburn fuels are compared with the OHTCs for NG. It was found that the growth of the layer of ash depositions over longer periods typically lowers OHTC, and the increased concentration of ash in gas phase promotes radiation in high-temperature zones during initial periods while decreasing the heat transfer in low-temperature zones. The ash analyses indicated that the bottom ash in the ash port contained a smaller percentage of combustibles with a higher FB percentage in the fuels, indicating better performance compared with coal because small particles in FB burn faster and the FB has higher volatile matter on a dry ash-free basis promoting more burn out. 16 refs., 12 figs., 6 tabs.« less

Fluidized bed coal combustion reactor

NASA Technical Reports Server (NTRS)

Moynihan, P. I.; Young, D. L. (Inventor)

1981-01-01

A fluidized bed coal reactor includes a combination nozzle-injector ash-removal unit formed by a grid of closely spaced open channels, each containing a worm screw conveyor, which function as continuous ash removal troughs. A pressurized air-coal mixture is introduced below the unit and is injected through the elongated nozzles formed by the spaces between the channels. The ash build-up in the troughs protects the worm screw conveyors as does the cooling action of the injected mixture. The ash layer and the pressure from the injectors support a fluidized flame combustion zone above the grid which heats water in boiler tubes disposed within and/or above the combustion zone and/or within the walls of the reactor.

Instrumental activation analysis of coal and fly ash with thermal and epithermal neutrons and short-lived nuclides

USGS Publications Warehouse

Steinnes, E.; Rowe, J.J.

1976-01-01

Instrumental neutron activation analysis is applied to the determination of about 25 elements in coals and fly ash by means of nuclides with half-lives of less than 48 h ; thermal and epithermal irradiations are used. The results indicate that epithermal activation is preferable for twelve of the elements (Ga, As, Br, Sr, In, Cs, Ba, La, Sm, Ho, W and U). Data for SRM 1632 (coal) and SRM 1633 (fly ash) compare favorably with the results obtained by other investigators. ?? 1976.

A novel silica alumina-based backfill material composed of coal refuse and fly ash.

PubMed

Yao, Yuan; Sun, Henghu

2012-04-30

In this paper, a systematic study was conducted to investigate a novel silica alumina-based backfill material composed of coal refuse and fly ash. The coal refuse and fly ash had different properties under various thermal activation temperatures (20 °C, 150 °C, 350 °C, 550 °C, 750 °C and 950 °C). It is known that a thermal activation temperature ranging from 20 °C to 950 °C significantly increases the flowability and pozzolanic properties of the coal refuse; however, the flowability of fly ash decreases when the activation temperature is higher than 550 °C because of a severe agglomeration phenomenon on its surface. An optimal design for this backfill material was determined to include an activated portion composed of 5% coal refuse at 750 °C and 15% fly ash at 20 °C. This combination yields the best performance with excellent flowability, a high compressive strength and a low bleeding rate. The microanalysis results corresponded well with the performance tests at different activation conditions. In the coal refuse, kaolinite peaks began to decrease because of their transformation into metakaolin at 550 °C. Chlorite peaks disappeared at 750 °C. Muscovite peaks decreased at 750 °C and disappeared at 950 °C. During this process, muscovite 2M(1) gradually dehydroxylated to muscovite HT. Furthermore, this paper examined the environmental acceptance and economic feasibility of this technology and found that this silica alumina-based backfill material composed of coal refuse and fly ash not only meets EPA requirements but also has several advantages in industry feasibility when compared with hydraulic backfill, rock backfill and paste backfill. Published by Elsevier B.V.

Simultaneous biosorption of selenium, arsenic and molybdenum with modified algal-based biochars.

PubMed

Johansson, Charlotte L; Paul, Nicholas A; de Nys, Rocky; Roberts, David A

2016-01-01

Ash disposal waters from coal-fired power stations present a challenging water treatment scenario as they contain high concentrations of the oxyanions Se, As and Mo which are difficult to remove through conventional techniques. In an innovative process, macroalgae can be treated with Fe and processed through slow pyrolysis into Fe-biochar which has a high affinity for oxyanions. However, the effect of production conditions on the efficacy of Fe-biochar is poorly understood. We produced Fe-biochar from two algal sources; "Gracilaria waste" (organic remnants after agar is extracted from cultivated Gracilaria) and the freshwater macroalgae Oedogonium. Pyrolysis experiments tested the effects of the concentration of Fe(3+) in pre-treatment, and pyrolysis temperatures, on the efficacy of the Fe-biochar. The efficacy of Fe-biochar increased with increasing concentrations of Fe(3+) in the pre-treatment solutions, and decreased with increasing pyrolysis temperatures. The optimized Fe-biochar for each biomass was produced by treatment with a 12.5% w/v Fe(3+) solution, followed by slow pyrolysis at 300 °C. The Fe-biochar produced in this way had higher a biosorption capacity for As and Mo (62.5-80.7 and 67.4-78.5 mg g(-1) respectively) than Se (14.9-38.8 mg g(-1)) in single-element mock effluents, and the Fe-biochar produced from Oedogonium had a higher capacity for all elements than the Fe-biochar produced from Gracilaria waste. Regardless, the optimal Fe-biochars from both biomass sources were able to effectively treat Se, As and Mo simultaneously in an ash disposal effluent from a power station. The production of Fe-biochar from macroalgae is a promising technique for treatment of complex effluents containing oxyanions. Copyright © 2015 Elsevier Ltd. All rights reserved.

Utilization of coal fly ash in solidification of liquid radioactive waste from research reactor.

PubMed

Osmanlioglu, Ahmet Erdal

2014-05-01

In this study, the potential utilization of fly ash was investigated as an additive in solidification process of radioactive waste sludge from research reactor. Coal formations include various percentages of natural radioactive elements; therefore, coal fly ash includes various levels of radioactivity. For this reason, fly ashes have to be evaluated for potential environmental implications in case of further usage in any construction material. But for use in solidification of radioactive sludge, the radiological effects of fly ash are in the range of radioactive waste management limits. The results show that fly ash has a strong fixing capacity for radioactive isotopes. Specimens with addition of 5-15% fly ash to concrete was observed to be sufficient to achieve the target compressive strength of 20 MPa required for near-surface disposal. An optimum mixture comprising 15% fly ash, 35% cement, and 50% radioactive waste sludge could provide the solidification required for long-term storage and disposal. The codisposal of radioactive fly ash with radioactive sludge by solidification decreases the usage of cement in solidification process. By this method, radioactive fly ash can become a valuable additive instead of industrial waste. This study supports the utilization of fly ash in industry and the solidification of radioactive waste in the nuclear industry.

High-performance self-compacting concrete with the use of coal burning waste

NASA Astrophysics Data System (ADS)

Bakhrakh, Anton; Solodov, Artyom; Naruts, Vitaly; Larsen, Oksana; Alimov, Lev; Voronin, Victor

2017-10-01

Today, thermal power plants are the main producers of energy in Russia. Most of thermal power plants use coal as fuel. The remaining waste of coal burning is ash, In Russia ash is usually kept at dumps. The amount of utilized ash is quite small, less than 13%. Meanwhile, each ash dump is a local ecological disaster. Ash dumps take a lot of place and destroy natural landscape. The use of fly ash in building materials can solve the problem of fly ash dumps in Russia. A lot of papers of scientists are devoted to the use of fly ash as filler in concrete. The main advantage of admixing fly ash in concrete is decrease of amount of used cement. This investigation was held to find out if it is possible to utilize fly ash by its use in high amounts in self-compacting concrete. During experiments three mixtures of SCC with different properties were obtained. The first one is experimental and shows the possibility of obtaining SCC with high compressive strength with 60% of fly ash from the mass of cement. Two other mixtures were optimized with the help of the math planning method to obtain high 7-day and 28-day high compressive strength.

Reuse of Coconut Shell, Rice Husk, and Coal Ash Blends in Geopolymer Synthesis

NASA Astrophysics Data System (ADS)

Walmiki Samadhi, Tjokorde; Wulandari, Winny; Prasetyo, Muhammad Iqbal; Rizki Fernando, Muhammad

2017-10-01

Mixtures of biomass and coal ashes are likely to be produced in increasing volume as biomass-based energy production is gaining importance in Indonesia. This work highlights the reuse of coconut shell ash (CSA), rice husk ash (RHA), and coal fly ash (FA) for geopolymer synthesis by an activator solution containing concentrated KOH and Na2SiO3. Ash blend compositions are varied according to a simplex-centroid mixture experimental design. Activator to ash mass ratios are varied from 0.8 to 2.0, the higher value being applied for ash compositions with higher Si/Al ratio. The impact of ash blend composition on early strength is adequately modeled by an incomplete quadratic mixture model. Overall, the ashes can produce geopolymer mortars with an early strength exceeding the Indonesian SNI 15-2049-2004 standard minimum value of 2.0 MPa. Good workability of the geopolymer is indicated by their initial setting times which are longer than the minimum value of 45 mins. Geopolymers composed predominantly of RHA composition exhibit poor strength and excessive setting time. FTIR spectroscopy confirms the geopolymerization of the ashes by the shift of the Si-O-Si/Al asymmetric stretching vibrational mode. Overall, these results point to the feasibility of geopolymerization as a reuse pathway for biomass combustion waste.

The Impact of Coal Combustion Fly Ash Used as a Supplemental Cementitious Material on the Leaching of Constituents from Cements and Concretes

EPA Science Inventory

The objective of this report is to compare the leaching of portland cement-based materials that have been prepared with and without coal combustion fly ash to illustrate whether there is evidence that the use of fly ash in cement and concrete products may result in increased leac...

Gasification of high ash, high ash fusion temperature bituminous coals

DOEpatents

Liu, Guohai; Vimalchand, Pannalal; Peng, WanWang

2015-11-13

This invention relates to gasification of high ash bituminous coals that have high ash fusion temperatures. The ash content can be in 15 to 45 weight percent range and ash fusion temperatures can be in 1150.degree. C. to 1500.degree. C. range as well as in excess of 1500.degree. C. In a preferred embodiment, such coals are dealt with a two stage gasification process--a relatively low temperature primary gasification step in a circulating fluidized bed transport gasifier followed by a high temperature partial oxidation step of residual char carbon and small quantities of tar. The system to process such coals further includes an internally circulating fluidized bed to effectively cool the high temperature syngas with the aid of an inert media and without the syngas contacting the heat transfer surfaces. A cyclone downstream of the syngas cooler, operating at relatively low temperatures, effectively reduces loading to a dust filtration unit. Nearly dust- and tar-free syngas for chemicals production or power generation and with over 90%, and preferably over about 98%, overall carbon conversion can be achieved with the preferred process, apparatus and methods outlined in this invention.

CO2 Biofixation by the Cyanobacterium Spirulina sp. LEB 18 and the Green Alga Chlorella fusca LEB 111 Grown Using Gas Effluents and Solid Residues of Thermoelectric Origin.

PubMed

da Silva Vaz, Bruna; Costa, Jorge Alberto Vieira; de Morais, Michele Greque

2016-01-01

The concentration of carbon dioxide (CO2) in the atmosphere has increased from 280 to 400 ppm in the last 10 years, and the coal-fired power plants are responsible for approximately 22 % of these emissions. The burning of fossil fuel also produces a great amount of solid waste that causes serious industrial and environmental problems. The biological processes become interesting alternative in combating pollution and developing new products. The objective of this study was to evaluate the CO2 biofixation potential of microalgae that were grown using gaseous effluents and solid residues of thermoelectric origin. The microalgae Chlorella fusca LEB 111 presented higher rate of CO2 biofixation (42.8 %) (p < 0.01) than did Spirulina sp. LEB 18. The values for the CO2 biofixation rates and the kinetic parameters of Spirulina and Chlorella cells grown using combustion gas did not differ significantly from those of cells grown using CO2 and a carbon source in the culture media. These microalgae could be grown using ash derived from coal combustion, using the minerals present in this residue as the source of the essential metals required for their growth and the CO2 derived from the combustion gas as their carbon source.

Health and environmental impacts of increased generation of coal ash and FGD sludges. Report to the Committee on Health and Ecological Effects of Increased Coal Utilization.

PubMed Central

Santhanam, C J; Lunt, R R; Johnson, S L; Cooper, C B; Thayer, P S; Jones, J W

1979-01-01

This paper focuses on the incremental impacts of coal ash and flue gas desulfurization (FGD) wastes associated with increased coal usage by utilities and industry under the National Energy Plan (NEP). In the paper, 1985 and 2000 are the assessment points using the baseline data taken from the Annual Environmental Analysis Report (AEAR, September 1977). In each EPA region, the potential mix of disposal options has been broadly estimated and impacts assessed therefrom. In addition, future use of advanced combustion techniques has been taken into account. The quantities of coal ash and FGD wastes depend on ash and sulfur content of the coal, emission regulations, the types of ash collection and FGD systems, and operating conditions of the systems and boiler. The disposal of these wastes is (or will be) subject to Federal and State regulations. The one key legal framework concerning environmental impact on land is the Resource Conservation and Recovery Act (RCRA). RCRA and related Federal and State laws provide a sufficient statutory basis for preventing significant adverse health and environmental impacts from coal ash and FGD waste disposal. However, much of the development and implementation of specific regulations lie ahead. FGD wastes and coal ash and FGD wastes are currently disposed of exclusively on land. The most common land disposal methods are inpoundments (ponds) and landfills, although some mine disposal is also practiced. The potential environmental impacts of this disposal are dependent on the characteristics of the disposal site, characteristics of the coal ash and FGD wastes, control method and the degree of control employed. In general, the major potential impacts are ground and surface water contamination and the "degradation" of large quantities of land. However, assuming land is available for disposal of these wastes, control technology exists for environmentally sound disposal. Because of existing increases in coal use, the possibility of significant environmental impacts, both regionally and nationally, exists regardless of whether the NEP scenario develops or not. Existing baseline data indicate that with sound control technology and successful development and implementation of existing regulatory framework, regional scale impacts are likely to be small; however, site-specific impacts could be significant and need to be evaluated on a case-by-case basis. Both Federal and privately-funded programs are developing additional data and information on disposal of FGD sludges and coal ash. Continuation of these programs will provide additional vital information in the future. However, further information in several areas if desirable: further data on levels of radionuclides and trace metals in these wastes: studies on biological impacts of trace metals; and completion of current and planned studies on disposal problems associated with advanced combustion techniques like fluid bed combustion. PMID:540614

Trace element partitioning behavior of coal gangue-fired CFB plant: experimental and equilibrium calculation.

PubMed

Zhang, Yingyi; Nakano, Jinichiro; Liu, Lili; Wang, Xidong; Zhang, Zuotai

2015-10-01

Energy recovery is a promising method for coal gangue utilization, during which the prevention of secondary pollution, especially toxic metal emission, is a significant issue in the development of coal gangue utilization. In the present study, investigation into trace element partitioning behavior from a coal gangue-fired power plant in Shanxi province, China, has been conducted. Besides the experimental analysis, thermodynamic equilibrium calculation was also conducted to help the further understanding on the effect of different parameters. Results showed that Hg, As, Be, and Cd were highly volatile elements in the combustion of coal gangue, which were notably enriched in fly ash and may be emitted into the environment via the gas phase. Cr and Mn were mostly non-volatile and were enriched in the bottom ash. Pb, Co, Zn, Cu, and Ni were semi-volatile elements and were enriched in the fly ash to varying degrees. Equilibrium calculations show that the air/fuel ratio and the presence of Cl highly affect the element volatility. The presence of mineral phases, such as aluminosilicates, depresses the volatility of elements by chemical immobilization and competition in Cl. The coal gangue, fly ash, and bottom ash all passed the toxicity characteristic leaching procedure (TCLP), and their alkalinity buffers the acidity of the solution and contributes to the low solubility of the trace elements.

Mercury and trace element distribution in density separates of a South African Highveld (#4) coal: Implications for mercury reduction and preparation of export coal

USGS Publications Warehouse

Kolker, Allan; Senior, Connie L.; van Alphen, Chris; Koenig, Alan E.; Geboy, Nicholas J.

2017-01-01

Eight density separates of Permian Highveld (#4) coal were investigated for partitioning of Hg and trace elements. The separates include float fractions obtained in heavy media having densities of 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, and 2.0 g/cm3, and the sink fraction for 2.0 g/cm3. Bulk analysis of the separates shows strong (R2 ≥ 0.80) positive correlations between pyritic sulfur and mercury, and between ash yield and both pyritic sulfur and mercury. Laser ablation (LA) ICP-MS analysis of individual pyrite grains in the separates confirms association of Hg and As with pyrite as indicated by bulk analysis. Other elements detected in pyrite by LA-ICP-MS include Mn, Co, Ni, Tl, and Pb. Results for the separates allow prediction of Hg, trace elements, and ash yields expected in specific South African coal products. These range from 0.06 ppm Hg and an ash yield of 11.5% ash for the export fraction to 0.47 ppm Hg and an ash yield of 60.9% for the discard (stone) fraction (dry basis). Results show pronounced differences expected between coal used for domestic power generation and coal which is exported.

Depositional history of the Fire Clay coal bed (Late Duckmantian), Eastern Kentucky, USA

USGS Publications Warehouse

Greb, S.F.; Eble, C.F.; Hower, J.C.

1999-01-01

More than 3800 coal thickness measurements, proximate analyses from 97 localities, and stratigraphic and sedimentological analyses from more than 300 outcrops and cores were used in conjunction with previously reported palynological and petrographic studies to map individual benches of the coal and document bench-scale variability in the Fire Clay (Hazard No. 4) coal bed across a 1860 km2 area of the Eastern Kentucky Coal Field. The bench architecture of the Fire Clay coal bed consists of uncommon leader benches, a persistent but variable lower bench, a widespread, and generally thick upper bench, and local, variable rider benches. Rheotrophic conditions are inferred for the leader benches and lower bench based on sedimentological associations, mixed palynomorph assemblages, locally common cannel coal layers, and generally high ash yields. The lower bench consistently exhibits vertical variability in petrography and palynology that reflects changing trophic conditions as topographic depressions infilled. Infilling also led to unconfined flooding and ultimately the drowning of the lower bench mire. The drowned mire was covered by an air-fall volcanic-ash deposit, which produced the characteristic flint clay parting. The extent and uniform thickness of the parting suggests that the ash layer was deposited in water on a relatively flat surface without a thick canopy or extensive standing vegetation across most of the study area. Ash deposits led to regional ponding and establishment of a second planar mire. Because the topography had become a broadly uniform, nutrient-rich surface, upper-bench peats became widespread with large areas of the mire distant to clastic sources. Vertical sections of thick (> 70 cm), low-ash yield, upper coal bench show a common palynomorph change from arborescent lycopod dominance upward to fern and densospore-producing, small lycopod dominance, inferred as a shift from planar to ombrotrophic mire phases. Domed mires appear to have been surrounded by wide areas of planar mires, where the coal was thinner (< 70 cm), higher in ash yield, and dominated by arborescent lycopods. Rectangular thickness trends suggest that syndepositional faulting influenced peat accumulation, and possibly the position of the domed mire phase. Faulting also influenced post-depositional clastic environments of deposition, resulting in sandstone channels with angular changes in orientation. Channels and lateral facies were locally draped by high-ash-yield rider coal benches, which sometimes merged with the upper coal bench. These arborescent-lycopod dominant rider coal benches were profoundly controlled by palcotopography, much like the leader coal benches. Each of the benches of coal documented here represent distinctly different mires that came together to form the Fire Clay coal bed, rather than a single mire periodically split by clastic influx. This is significant as each bench of the coal has its own characteristics, which contribute to the total coal characteristics. The large data set allows interpretation of both vertical and lateral limits to postulated domed phases in the upper coal bench, and to the delineation of subtle tectonic structures that allow for meaningful thickness projections beyond the limits of present mining.A study was conducted to analyze the depositional history of the Fire Clay coal bed in the eastern Kentucky coal field. The study involved over 3800 coal thickness measurements, proximate analyses from 97 localities, and stratigraphic and sedimentological analyses from more than 300 outcrops and cores in conjunction with previously reported palynological and petrographic studies to map individual benches of the coal and document bench-scale variability.

JV Task 107- Pilot-Scale Emission Control Technology Testing for Constellation Energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Michael Jones; Brandon Pavlish; Stephen Sollom

2007-06-30

An Indonesian, Colombian, and Russian coal were tested in the Energy & Environmental Research Center's combustion test facility for their performance and an evaluation of mercury release and capture with selected additives in both electrostatic precipitator and baghouse configurations. Sorbents included the carbon-based materials NORIT DARCO Hg, Sorbent Technologies B-PAC and B-PAC LC, STI Rejects provided by Constellation Energy, and Envergex e-Sorb, along with ChemMod's high-temperature additive. Each coal was evaluated over several days and compared. Ash-fouling tests were conducted, and mercury levels were monitored using continuous mercury monitors (CMMs). The Ontario Hydro mercury sampling method was also utilized. Themore » Indonesian coal had the lowest ash content, lowest sulfur content, and lowest energy content of the three coals tested. The Colombian coal had the highest mercury content and did contain a significant level of selenium which can interfere with the ability of a CMM to monitor mercury in the gas stream. All sorbents displayed very favorable results. In most cases, mercury removal greater than 86% could be obtained. The Indonesian coal displayed the best mercury removal with sorbent addition. A maximum removal of 97% was measured with this coal using Envergex's carbon-based sorbent at a rate of 4 lb/Macf across an electrostatic precipitator. The high ash and selenium content of the Colombian coal caused it to be a problematic fuel, and ash plugging of the test furnace was a real concern. Problems with the baghouse module led to limited testing. Results indicated that native capture across the baghouse for each coal type was significant enough not to warrant sorbent addition necessary. The fouling potential was the lowest for the Indonesian coal. Low sulfur content contributes to the poor potential for fouling, as witnessed by the lack of deposits during testing. The Russian and Colombian coals had a much higher potential for fouling primarily because of their high ash contents, but the potential was highest for the Colombian coal. Of the three coals tested, the Colombian would be the least desirable.« less

Radioactivity of coals and ash and slag wastes at coal-fired thermal power plants

NASA Astrophysics Data System (ADS)

Krylov, D. A.; Sidorova, G. P.

2013-04-01

This paper presents an analysis of published data on the content of radioactive nuclides in coals originating from various coal deposits, and in ash and slag wastes produced at coal-fired thermal power plants, as well as in fly ash emitted from thermal power plants into the atmosphere. Problems related to the use of coals with an elevated content of natural radionuclides (NRNs) and methods of their solution implemented at the Urtuyskoe coalfield are dealt with. Data on the analysis of Transbaikal coals for the NRN content, as well as weighted mean content of uranium and thorium in coals from the Siberian Region, are given. In order to reduce irradiation of plant personnel and the population of the areas where coal producers and coal-fired thermal power plants are located, it is necessary to organize very careful control of the NRN content in both coals and products of their combustion that are released into the environment. To solve the problem related to the control of radioactivity, the centralized approach and creation of a proper normative base are needed. Experience gained in developing the Urtuyskoe coalfield shows that it is possible to create an efficient system of coal quality control with respect to the radiation hygiene factor and provide protection of the environment and health of the population.

Influence of coal ash and slag dumping on dump waste waters of the Kostolac power plants (Serbia)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Popovic, A.; Djinovic, J.

2006-10-01

The content of selected trace and major elements in the river water used for transport, as well as in the subcategories of the waste waters (overflow and drainage) were analyzed in order to establish the influence of transport and dumping of coal ash and slag from the 'Kostolac A' and 'Kostolac B' power plants located 100 km from Belgrade (Serbia). It was found that during transport of coal ash and slag to the dump, the water used for transport becomes enriched with manganese, nickel, zinc, chromium, vanadium, titanium, cobalt, arsenic, aluminum, and silicon, while more calcium, iron, cadmium, and leadmore » are adsorbed by the ash and slag than is released from them. There is also an equilibrium between the release and adsorption processes of copper and magnesium during transport. The vertical penetration of the water used for transport results in a release of calcium, magnesium, manganese, and cadmium to the environment, while iron, nickel, zinc, chromium, copper, lead, vanadium, titanium, cobalt, and arsenic are adsorbed by the fractions of coal ash and slag in the dump.« less

Factors affecting the geochemistry of a thick, subbituminous coal bed in the Powder River Basin: volcanic, detrital, and peat-forming processes

USGS Publications Warehouse

Crowley, S.S.; Ruppert, L.F.; Belkin, H.E.; Stanton, R.W.; Moore, T.A.

1993-01-01

The inorganic geochemistry and mineralogy of three cores from the Anderson-Dietz 1 coal bed, a 15.2-m-thick subbituminous coal bed in the Tongue River Member (Paleocene) of the Fort Union Formation, were examined (1) to determine if the cores could be correlated by geochemical composition alone over a total distance of 2 km and (2) to identify the major factors that influenced the geochemistry of the coal bed. Chemical data (46 elements on a coal-ash basis) for 81 coal samples and 4 carbonaceous rock samples, with most samples representing a 0.6-m-thick (2-ft) interval of core, were grouped into compositional clusters by means of cluster analysis. Seven major clusters were produced; two of these clusters can be used to correlate the coal bed throughout the study area. Data from scanning electron and optical microscope analyses indicate that several factors influenced the geochemistry of the Anderson-Dietz 1 coal bed. The majority of mineral grains in the coal bed are interpreted to be detrital (water borne); evidence includes the presence of rounded to subrounded quartz grains having two-phase, aqueous fluid inclusions characteristic of hydrothermal or low-to-moderate grade metamorphic quartz. These quartz grains are found throughout the coal bed but are most abundant in samples from the midpart of the bed, which was influenced by detrital input associated with the deposition of the clastic rocks that form the split between the Anderson and Dietz 1 coal beds 900 m to the east of the study area. In addition to the detrital minerals mentioned above, volcanic ash that was fluvially transported to the sites of peat deposition or possibly deposited as air-fall volcanic ash also affected the geochemistry of the coal bed. For example, crandallite(?), a mineral reported to form as an alteration product of volcanic ash, is found in seven samples from the coal bed. The presence of quartz grains containing silicate-melt inclusions in eight samples from the coal bed.provides further support for a volcanic ash component. Other factors that probably affected the geochemistry of the coal bed include (1) detrital input associated with the deposition of the roof rocks of the coal bed, (2) peat-forming processes and plant material, and (3) epigenetic ground-water flow. ?? 1993.

Rare and Rare-Earth Metals in Coal Processing Waste

NASA Astrophysics Data System (ADS)

Cherkasova, Tatiana; Cherkasova, Elizaveta; Tikhomirova, Anastasia; Bobrovni-kova, Alyona; Goryunova, Irina

2017-11-01

An urgent issue for power plants operating on solid fuels (coal) is the issue of utilization or use of accumulated production waste - ash and slag materials - in the related production. Ash-slag materials are classified as "waste", usually grade 5; tens of millions of tons of them being pro-duced annually in the Kemerovo region, which threatens the ecology of the region. At the same time, ash and slag is a very promising raw material. The use of this material as a base for the final product allows us to signifi-cantly expand the possibilities of using coal. The most widespread is the system of ash and slag involving in construction or as a replacement for sand in road construction, or as an additive to building mixtures. However, there are both industrially valuable and environmentally dangerous ele-ments in ash-slag materials. Ash-slag materials can be considered as inde-pendent ore deposits located on the surface and requiring the costs of their extraction.

Power recovery system for coal liquefaction process

DOEpatents

Horton, Joel R.

1985-01-01

Method and apparatus for minimizing energy required to inject reactant such as coal-oil slurry into a reaction vessel, using high pressure effluent from the latter to displace the reactant from a containment vessel into the reaction vessel with assistance of low pressure pump. Effluent is degassed in the containment vessel, and a heel of the degassed effluent is maintained between incoming effluent and reactant in the containment vessel.

In-plant testing of a novel coal cleaning circuit using advanced technologies. Final technical report, September 1, 1995--August 31, 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

Honaker, R.Q.; Reed, S.; Mohanty, M.K.

1997-05-01

A circuit comprised of advanced fine coal cleaning technologies was evaluated in an operating preparation plant to determine circuit performance and to compare the performance with current technologies used to treat -16 mesh fine coal. The circuit integrated a Floatex hydrosizer, a Falcon enhanced gravity concentrator and a Jameson flotation cell. A Packed-Column was used to provide additional reductions in the pyritic sulfur and ash contents by treatment of the Floatex-Falcon-Jameson circuit product. For a low sulfur Illinois No. 5 coal, the pyritic sulfur content was reduced from 0.67% to 0.34% at a combustible recovery of 93.2%. The ash contentmore » was decreased from 27.6% to 5.84%, which equates to an organic efficiency of 95% according to gravity-based washability data. The separation performance achieved on a high sulfur Illinois No. 5 coal resulted in the rejection of 72.7% of the pyritic sulfur and 82.3% of the ash-forming material at a recovery of 8 1 %. Subsequent pulverization of the cleaned product and retreatment in a Falcon concentrator and Packed-Column resulted in overall circuit ash and pyritic sulfur rejections of 89% and 93%, respectively, which yielded a pyritic sulfur content reduction from 2.43% to 0.30%. This separation reduced the sulfur dioxide emission rating of an Illinois No. 5 coal from 6.21 to 1.75 lbs SO{sub 2}/MBTU, which is Phase I compliance coal. A comparison of the results obtained from the Floatex-Falcon-Jameson circuit with those of the existing circuit revealed that the novel fine coal circuit provides 10% to 20% improvement in mass yield to the concentrate while rejecting greater amounts of ash and pyritic sulfur.« less

Coal fly ash as a resource for rare earth elements.

PubMed

Franus, Wojciech; Wiatros-Motyka, Małgorzata M; Wdowin, Magdalena

2015-06-01

Rare earth elements (REE) have been recognised as critical raw materials, crucial for many clean technologies. As the gap between their global demand and supply increases, the search for their alternative resources becomes more and more important, especially for the countries which depend highly on their import. Coal fly ash (CFA), which when not utilised is considered waste, has been regarded as the possible source of many elements, including REE. Due to the increase in the energy demand, CFA production is expected to grow, making research into the use of this material a necessity. As Poland is the second biggest coal consumer in the European Union, the authors have studied different coal fly ashes from ten Polish power plants for their rare earth element content. All the fly ashes have a broadly similar distribution of rear earth elements, with light REE being dominant. Most of the samples have REE content relatively high and according to Seredin and Dai (Int J Coal Geol 94: 67-93, 2012) classification can be considered promising REE raw materials.

About fly ash and other residues from burning coal.

DOT National Transportation Integrated Search

1982-01-01

This report has been prepared for the benefit of these persons involved in highway construction who are not familiar with coal ash terminology. The information presented will, it is hoped, assist them in avoiding confusion relating to the general cha...

Physical and Chemical Character of Fly Ash of Coal Fired Power Plant in Java

NASA Astrophysics Data System (ADS)

Triwulan; Priadana, K. A.; Ekaputri, J. J.; Bayuaji, R.

2017-11-01

Quality of fly ash is varying widely in the field, it depends on the combustion process and the quality of the basic ingredients, namely coal. It will affect the physical and mechanical properties of the concrete mixtures used. This study used 12 samples of fly ash. The physical and chemical properties and finesse modulus were analyzed. The fly ash was mixed with OPC (Ordinary Portland Cement) with the proportion of 20% fly ash and 80% OPC. The specimens were form with mortar dimension of 5cm x 5 cm. The test was affected by the correlation of fly ash fineness modulus to compressive strength, correlation density of fly ash to compressive strength, and correlation of carbon content to the compressive strength.

Evidence of Coal-Fly-Ash Toxic Chemical Geoengineering in the Troposphere: Consequences for Public Health.

PubMed

Herndon, J Marvin

2015-08-11

The widespread, intentional and increasingly frequent chemical emplacement in the troposphere has gone unidentified and unremarked in the scientific literature for years. The author presents evidence that toxic coal combustion fly ash is the most likely aerosolized particulate sprayed by tanker-jets for geoengineering, weather-modification and climate-modification purposes and describes some of the multifold consequences on public health. Two methods are employed: (1) Comparison of 8 elements analyzed in rainwater, leached from aerosolized particulates, with corresponding elements leached into water from coal fly ash in published laboratory experiments, and (2) Comparison of 14 elements analyzed in dust collected outdoors on a high-efficiency particulate air (HEPA) filter with corresponding elements analyzed in un-leached coal fly ash material. The results show: (1) the assemblage of elements in rainwater and in the corresponding experimental leachate are essentially identical. At a 99% confidence interval, they have identical means (T-test) and identical variances (F-test); and (2) the assemblage of elements in the HEPA dust and in the corresponding average un-leached coal fly ash are likewise essentially identical. The consequences on public health are profound, including exposure to a variety of toxic heavy metals, radioactive elements, and neurologically-implicated chemically mobile aluminum released by body moisture in situ after inhalation or through transdermal induction.

DEVELOPMENT, TESTING, AND DEMONSTRATION OF AN OPTIMAL FINE COAL CLEANING CIRCUIT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steven R. Hadley; R. Mike Mishra; Michael Placha

1999-01-27

The objective of this project was to improve the efficiency of the fine coal froth flotation circuit in commercial coal preparation plants. The plant selected for this project, Cyprus Emerald Coal Preparation Plant, cleans 1200-1400 tph of Pittsburgh seam raw coal and uses conventional flotation cells to clean the minus 100-mesh size fraction. The amount of coal in this size fraction is approximately 80 tph with an average ash content of 35%. The project was carried out in two phases. In Phase I, four advanced flotation cells, i.e., a Jameson cell, an Outokumpu HG tank cell, an open column, andmore » a packed column cell, were subjected to bench-scale testing and demonstration. In Phase II, two of these flotation cells, the Jameson cell and the packed column, were subjected to in-plant, proof-of-concept (POC) pilot plant testing both individually and in two-stage combination in order to ascertain whether a two-stage circuit results in lower levelized production costs. The bench-scale results indicated that the Jameson cell and packed column cell would be amenable to the single- and two-stage flotation approach. POC tests using these cells determined that single-stage coal matter recovery (CMR) of 85% was possible with a product ash content of 5.5-7%. Two-stage operation resulted in a coal recovery of 90% with a clean coal ash content of 6-7.5%. This compares favorably with the plant flotation circuit recovery of 80% at a clean coal ash of 11%.« less

A pilot study of mercury liberation and capture from coal-fired power plant fly ash.

PubMed

Li, Jin; Gao, Xiaobing; Goeckner, Bryna; Kollakowsky, Dave; Ramme, Bruce

2005-03-01

The coal-fired electric utility generation industry has been identified as the largest anthropogenic source of mercury (Hg) emissions in the United States. One of the promising techniques for Hg removal from flue gas is activated carbon injection (ACI). The aim of this project was to liberate Hg bound to fly ash and activated carbon after ACI and provide high-quality coal combustion products for use in construction materials. Both bench- and pilot-scale tests were conducted to liberate Hg using a thermal desorption process. The results indicated that up to 90% of the Hg could be liberated from the fly ash or fly-ash-and-activated-carbon mixture using a pilot-scale apparatus (air slide) at 538 degrees C with a very short retention time (less than 1 min). Scanning electron microscope (SEM) evaluation indicated no significant change in fly ash carbon particle morphology following the thermal treatment. Fly ash particles collected in the baghouse of the pilot-scale apparatus were smaller in size than those collected at the exit of the air slide. A similar trend was observed in carbon particles separated from the fly ash using froth flotation. The results of this study suggest a means for power plants to reduce the level of Hg in coal-combustion products and potentially recycle activated carbon while maintaining the resale value of fly ash. This technology is in the process of being patented.

Decontamination of coal mine effluent generated at the Rajrappa coal mine using phytoremediation technology.

PubMed

Lakra, Kalpana C; Lal, B; Banerjee, T K

2017-06-03

Toxicity of the effluent generated at the Rajrappa coal mine complex under the Central Coalfields Limited (CCL, a subsidiary of Coal India Limited) in Jharkhand, India was investigated. The concentrations (mg L -1 ) of all the toxic metals (Fe, Mn, Ni, Zn, Cu, Pb, Cr, and Cd) in the coal mine effluent were above the safe limit suggested by the Environmental Protection Agency (EPA 2003). Among these, Fe showed the highest concentration (18.21 ± 3.865), while Cr had the lowest effluent concentration (0.15 ± 0.014). Efforts were also made to detoxify the effluent using two species of aquatic macrophytes namely "'Salvinia molesta and Pistia stratiotes." After 10 days of phytoremediation, S. molesta removed Pb (96.96%) > Ni (97.01%) > Cu (96.77%) > Zn (96.38%) > Mn (96.22%) > Fe (94.12%) > Cr (92.85%) > Cd (80.99%), and P. stratiotes removed Pb (96.21%) > Fe (94.34%) > Ni (92.53%) > Mn (85.24%) > Zn (79.51%) > Cr (78.57%) > Cu (74.19%) > Cd (72.72%). The impact of coal mine exposure on chlorophyll content showed a significant decrease of 42.49% and 24.54% from control values in S. molesta and P. stratiotes, respectively, perhaps due to the damage inflicted by the toxic metals, leading to the decay of plant tissues.

Environmentally friendly use of non-coal ashes in Sweden.

PubMed

Ribbing, C

2007-01-01

The Swedish Thermal Engineering Research Institute (Värmeforsk) initiated an applied research program "Environmentally friendly use of non-coal ashes", in 2002. The program aims at increasing knowledge on the by-products of energy production and their application. The goal of formulating technical and environmental guidelines and assessments is a major point of the program, which is supported by about forty authorities and private organisations. The programme has been divided into four areas: recycling of ashes to forests, geotechnical applications, use in landfilling, and environmental aspects and chemistry. Among all results obtained, the following progress is shown: *Evidence for the positive effects of spreading ashes on forest growth. *A proposal for environmental guidelines on the utilisation of ashes in construction. *A handbook for using non-coal fly ashes in unpaved roads. *Technical and environmental assessments of MSWI bottom ashes in road construction. *Development of the use of ashes with municipal wastewater sludge as a cover for landfills and mine tailings. *Use of ashes from bio-fuels in concrete and replacement of cement in stoop mining. *A method to classify those by-products from combustion that have mirror entries in the EWC as a hazardous or non-hazardous compound. The Ash Programme has also made it possible to increase knowledge on ashes as valuable materials, on quality assurance and on markets for recovered materials.

Intra- and inter-unit variation in fly ash petrography and mercury adsorption: Examples from a western Kentucky power station

USGS Publications Warehouse

Hower, J.C.; Finkelman, R.B.; Rathbone, R.F.; Goodman, J.

2000-01-01

Fly ash was collected from eight mechanical and 10 baghouse hoppers at each of the twin 150-MW wall-fired units in a western Kentucky power station. The fuel burned at that time was a blend of many low-sulfur, high-volatile bituminous Central Appalachian coals. The baghouse ash showed less variation between units than the mechanical hoppers. The mechanical fly ash, coarser than the baghouse ash, showed significant differences in the amount of total carbon and in the ratio of isotropic coke to both total carbon and total coke - the latter excluding inertinite and other unburned, uncoked coal. There was no significant variation in proportions of inorganic fly ash constituents. The inter-unit differences in the amount and forms of mechanical fly ash carbon appear to be related to differences in pulverizer efficiency, leading to greater amounts of coarse coal, therefore unburned carbon, in one of the units. Mercury capture is a function of both the total carbon content and the gas temperature at the point of fly ash separation, mercury content increasing with an increase in carbon for a specific collection system. Mercury adsorption on fly ash carbon increases at lower flue-gas temperatures. Baghouse fly ash, collected at a lower temperature than the higher-carbon mechanically separated fly ash, contains a significantly greater amount of Hg.

Geochemistry of an abandoned landfill containing coal combustion waste: Implications for remediation

Treesearch

Christopher Barton; Linda Paddock; Christopher Romanek; John Seaman

2001-01-01

The 488-D Ash Basin (488-DAB) is an unlined, earthen landfill containing approximately one million tons of dry ash and coal reject material at the U.S. Department of Energy's Savannah River Site, SC. The pyritic nature of the coal rejects has resulted in the formation of acidic drainage (AD), which has contributed to groundwater deterioration and threatened biota...

Metal attenuation processes in a landfill containing coal combustion waste: implications for remediation

Treesearch

Christopher Barton; Lindy Paddock; Christopher Romanek; Sally Maharaj; John Seaman

2005-01-01

The 488-D Ash Basin (488-DAB) is an unlined, earthen landfill containing approximately 1 million t of dry ash and coal reject material at the U.S. Department of Energy's Savannah River Site, South Carolina. The pyritic nature of the coal rejects has resulted in the formation of acidic drainage, which has contributed to groundwater deterioration and threatened...

Coal ash in Israel: Natural resource or environmental hazard

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sheps, S.; Davidi, S.; Cohen, H.

1997-12-31

Coal combustion in Israeli power plants produces 1,000,000 tonnes of ash annually. Most of the ash (55%) is used as cement additive. Since the expansion of coal combustion is much faster than the development of cement production, large amounts of fly ash are expected to accumulate in the next decade. Thus the environmental problem may be exacerbated if other means of utilization (e. g. embankments and marine reclamation or utilization as a chemical reagent) will not be possible in the future. Unlike other countries overseas, coal ash is defined in Israel as hazardous material, thus any disposal or utilization schememore » requires a special permit. The main concern is that pollution from the ash will leach out and contaminate the proximal ground water. The authors have decided to check the leaching behavior of South-African and Colombian fly ashes (the most abundant in Israel) using the following methods: (a) the improved EPA-TCLP 1311 (used in the US); (b) the EU-CEN/TC292/WG2 (declared recently as the method in the European Community); and (c) the NVN2508 method. The first two methods are batch methods and the third a flow through column method. The main constituents of the ash are listed along with the trace elements found. It has been observed that no appreciable amount of most trace elements are dissolved from the ash except that of chromium which exceeds the drinking water limits. Furthermore most of the leached chromium is in the hexavalent form which is considered as carcinogenic. The effect of different parameters and the risk involved in leaching out of trace elements from the fly ash to the underground water aquifer will be discussed in detail.« less

Characterization of Fly and Bottom Ashes Mixtures Treated using Sodium Lauryl Sulphate and Polyvinyl Alcohol

NASA Astrophysics Data System (ADS)

Robert, C. G.; Ayob, A.; Zaki, M. F. Muhammad; Razali, M. E.; Lew, E. V.; Hong, P. Y.

2018-03-01

Malaysia promotes coal as an option for solid fuel in electric power generation. Demanding of electricity needs, therefore, has led to increase the coal consumption and thus producing more coal waste products. The disposal of coal waste ashes has been a main concern to power generation station due to the need of disposal sites and operational costs. This study investigates the composition of fly ash (FA) and bottom ash (BA) mixtures with difference component percentage treated with sodium lauryl sulphate (SLS) and polyvinyl alcohol (PVA) at 1.5 and 2.5 wt% solutions and examined in terms of specific gravity, pH, maximum dry density properties, and its surface morphology. Although the chemical composition of the SLS and PVA treated fly and bottom ashes studied in this current work is not altered extensively, significant changes could be observed in its physicochemical properties. Chemically treated fly and bottom ashes mixtures with SLS and PVA at 1.5 wt% solution exhibited specific gravity of 1.97 to 2.92 and high pH values within range of 9.28 to 10.52. The mixture of BA:FA=0:1 ratio depicting high maximum dry density of 1.35 to 1.56 g/cm3 in both SLS and PVA solutions at 1.5 and 2.5 wt%. Scanning electron microscopy image shows distinct surface morphologies of SLS-treated fly and bottom ashes mixture that the particles are packed closely, strongly bonded similar to popcorn shape due to the effect of active silanol groups acted on coal ashes surface with the presence of Al-O/Si-O/other oxides. These findings suggest that higher level of chemical interaction between the fly and bottom ashes particles, significantly enhances pozzolanic reactions such as shear strength, plasticity, cementing properties, and thus other engineering properties.

Characteristics of fly ashes from full-scale coal-fired power plants and their relationship to mercury adsorption

USGS Publications Warehouse

Lu, Y.; Rostam-Abadi, M.; Chang, R.; Richardson, C.; Paradis, J.

2007-01-01

Nine fly ash samples were collected from the particulate collection devices (baghouse or electrostatic precipitator) of four full-scale pulverized coal (PC) utility boilers burning eastern bituminous coals (EB-PC ashes) and three cyclone utility boilers burning either Powder River Basin (PRB) coals or PRB blends,(PRB-CYC ashes). As-received fly ash samples were mechanically sieved to obtain six size fractions. Unburned carbon (UBC) content, mercury content, and Brunauer-Emmett-Teller (BET)-N2 surface areas of as-received fly ashes and their size fractions were measured. In addition, UBC particles were examined by scanning electron microscopy, high-resolution transmission microscopy, and thermogravimetry to obtain information on their surface morphology, structure, and oxidation reactivity. It was found that the UBC particles contained amorphous carbon, ribbon-shaped graphitic carbon, and highly ordered graphite structures. The mercury contents of the UBCs (Hg/UBC, in ppm) in raw ash samples were comparable to those of the UBC-enriched samples, indicating that mercury was mainly adsorbed on the UBC in fly ash. The UBC content decreased with a decreasing particle size range for all nine ashes. There was no correlation between the mercury and UBC contents of different size fractions of as-received ashes. The mercury content of the UBCs in each size fraction, however, generally increased with a decreasing particle size for the nine ashes. The mercury contents and surface areas of the UBCs in the PRB-CYC ashes were about 8 and 3 times higher than UBCs in the EB-PC ashes, respectively. It appeared that both the particle size and surface area of UBC could contribute to mercury capture. The particle size of the UBC in PRB-CYC ash and thus the external mass transfer was found to be the major factor impacting the mercury adsorption. Both the particle size and surface reactivity of the UBC in EB-PC ash, which generally had a lower carbon oxidation reactivity than the PRB-PC ashes, appeared to be important for the mercury adsorption. ?? 2007 American Chemical Society.

FILTRATION MODEL FOR COAL FLY ASH WITH GLASS FABRICS

EPA Science Inventory

The report describes a new mathematical model for predicting woven glass filter performance with coal fly ash aerosols from utility boilers. Its data base included: an extensive bench- and pilot-scale laboratory investigation of several dust/fabric combinations; field data from t...

Removal of ash, sulfur, and trace elements of environmental concern from eight selected Illinois coals

USGS Publications Warehouse

Demir, I.

1998-01-01

Release analysis (RA) and float-sink (F-S) data were generated to assess the beneficiation potential of washed coals from selected Illinois coal preparation plants through the use of advanced physical cleaning at -60 mesh size. Generally, the F-S process removed greater amounts of ash, sulfur, and trace elements of environmental concern from the coals than the RA process, indicating that the cleanability of Illinois coals by advanced methods can be estimated best by F-S testing. At an 80%-combustibles recovery, the ash yield in the clean F-S products decreased by 47-75%, relative to the parent coals. Average decreases for the elements As(67%), Cd(78%), Hg(73%), Mn(71%), and P(66%) exceeded the average decrease for ash yield (55%). Average decreases for other elements were: Co(31%), Cr(27%), F(39%), Ni(25%), Pb(50%), S(28%), Sb(20%), Se(39), Th(32%), and U(8%). Only Be was enriched (up to 120%) in the clean products relative to the parent coals. These results suggested that the concentration of elements with relatively high atmospheric mobilities (As, Cd, F, Hg, Pb, and Se) during coal combustion can be reduced substantially in Illinois coals through the use of advanced physical cleaning. Advanced physical cleaning can be effective also for the removal of inorganic S. Environmental risks from the emission of other elements with enrichment or relatively low cleanabilities could be small because these elements generally have very low concentrations in Illinois coals or are largely retained in solid residues during coal combustion. ?? 1998 OPA (Overseas Publishers Association) N.V. Published by license under the Gordon and Breach Science Publishers imprint.

Leaching of polycyclic aromatic hydrocarbons from power plant lignite ash--influence of parameters important for environmental pollution.

PubMed

Pergal, Miodrag M; Relić, Dubravka; Tešić, Zivoslav Lj; Popović, Aleksandar R

2014-03-01

Nikola Tesla B power plant (TENT B), located at the Sava River, in Obrenovac, 50 km west from the Serbian's capital, Belgrade, is the second largest coal-fired power plant in the country, consisting of two blocks, each of 620 MW capacity. In order to investigate the threat polycyclic aromatic hydrocarbons (PAHs) from deposited coal ash, obtained by coal combustion in this power plant, can represent for the surrounding environment, samples of coal ash were submitted to extraction with river water used for transport of coal ash to the dump, as well as with water of different ionic strength and acidity. It was found that, out of 16 EPA priority PAHs, only naphthalene, acenaphthylene, fluorene, phenantrene, fluoranthene, and pyrene were found in measurable concentrations in the different extracts. Their combined concentration was around 0.1 μg/L, so they do not, in terms of leached concentrations, represent serious danger for the surrounding environment. In all cases of established (and leached) PAH compounds, changes of ionic strength, acidity, or the presence of organic compounds in river water may to some extent influence the leached concentrations. However, under the examined conditions, similar to those present in the environment, leached concentrations were not more than 50 % greater than the concentrations leached by distilled water. Therefore, water desorption is likely the most important mechanism responsible for leaching of PAH compounds from filter coal ash.

The Leaching of Aluminium In Spanish Clays, Coal Mining Wastes and Coal Fly Ashes by Sulphuric Acid.

NASA Astrophysics Data System (ADS)

Fernández, A. M.; Ibáñez, J. L.; Llavona, M. A.; Zapico, R.

The acid leaching of aluminium from several non traditional ores, bayerite, kaolinite, different clays, coal mining wastes and coal fly ashes, and the kinetic of their dissolution are described. The effects of time, temperature, acid concentration, sample calcination, particle size were examined. The leaching of aluminium is dependent on acid concentration and strongly on temperature. Generally, the time to reach a fixed percentage of dissolution decreases with increasing acid concentration in the range 6% to 40% acid by weight. On clays and coal mining wastes a good relation between Al removal and ratio kaolinite/illite was also observed at all temperatures and acid concentration tested. Coal fly ashes are particles that were heated at very high temperatures in the power station and Al compounds were transformed into mullite and so Al recovery was minor. Several rate equations describing the kinetics of the leach reaction were discussed and Kinetic parameters and activation energy values of samples are presented.

Synthesis of geopolymer from biomass-coal ash blends

NASA Astrophysics Data System (ADS)

Samadhi, Tjokorde Walmiki; Wulandari, Winny; Prasetyo, Muhammad Iqbal; Fernando, Muhammad Rizki; Purbasari, Aprilina

2017-09-01

Geopolymer is an environmentally attractive Portland cement substitute, owing to its lower carbon footprint and its ability to consume various aluminosilicate waste materials as its precursors. This work describes the development of geopolymer formulation based on biomass-coal ash blends, which is predicted to be the prevalent type of waste when biomass-based thermal energy production becomes mainstream in Indonesia. The ash blends contain an ASTM Class F coal fly ash (FA), rice husk ash (RHA), and coconut shell ash (CSA). A mixture of Na2SiO3 and concentrated KOH is used as the activator solution. A preliminary experiment identified the appropriate activator/ash mass ratio to be 2.0, while the activator Na2SiO3/KOH ratio varies from 0.8 to 2.0 with increasing ash blend Si/Al ratio. Both non-blended FA and CSA are able to produce geopolymer mortars with 7-day compressive strength exceeding the Indonesian national SNI 15-2049-2004 standard minimum value of 2.0 MPa stipulated for Portland cement mortars. Ash blends have to be formulated with a maximum RHA content of approximately 50 %-mass to yield satisfactory 7-day strength. No optimum ash blend composition is identified within the simplex ternary ash blend compositional region. The strength decreases with Si/Al ratio of the ash blends due to increasing amount of unreacted silicate raw materials at the end of the geopolymer hardening period. Overall, it is confirmed that CSA and blended RHA are feasible raw materials for geopolymer production..

Sulfur-bearing coatings on fly ash from a coal-fired power plant: Composition, origin, and influence on ash alteration

USGS Publications Warehouse

Fishman, N.S.; Rice, C.A.; Breit, G.N.; Johnson, R.D.

1999-01-01

Fly ash samples collected from two locations in the exhaust stream of a coal-fired power plant differ markedly with respect to the abundance of thin (???0.1 ??m) sulfur-rich surface coatings that are observable by scanning electron microscopy. The coatings, tentatively identified as an aluminum-potassium-sulfate phase, probably form upon reaction between condensed sulfuric acid aerosols and glass surfaces, and are preferentially concentrated on ash exposed to exhaust stream gases for longer. The coatings are highly soluble and if sufficiently abundant, can impart an acidic pH to solutions initially in contact with ash. These observations suggest that proposals for ash use and predictions of ash behavior during disposal should consider the transient, acid-generating potential of some ash fractions and the possible effects on initial ash leachability and alteration. ?? 1998 Elsevier Science Ltd.

Attrition of coal ash particles in a fluidized-bed reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tomeczek, J.; Mocek, P.

2007-05-15

Experimental data of ash-particles attrition in a fluidized bed is presented, and also the results of modeling. Five sizes of ash particles (1.02-1.25; 1.25-1.6; 1.6-2.0; 2.0-5.0; 5.0-10.0 mm) produced in an industrial CFB boiler were examined. A new model of mechanical attrition has been proposed which incorporates new parameters: the shape factor of particles and the ratio of the bed height to bed diameter, strongly influencing the rate of bed mass loss. The model describes very well experimental data for coal-ash particles attrition. The attrition-rate coefficient for ash particles was evaluated.

Characterization of Rare Earth Element Minerals in Coal Utilization Byproducts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Montross, Scott N.; Verba, Circe A.; Collins, Keith

The United States currently produces over 100 million tons of coal utilization byproducts (CUB) per year in the form of fly ash, bottom ash, slag, and flue gas (American Coal Ash Association (ACCA), 2015). But this “waste material” also contains potentially useful levels of rare earth elements (REE). Rare earth elements are crucial for many existing and emerging technologies, but the U.S. lacks a domestic, sustainable REE source. Our project explored the possibility of developing a supply of REEs for U.S. technologies by extracting REEs from CUBs. This work offers the potential to reduce our dependence on other countries formore » supply of these critical elements (NETL, REE 2016 Project Portfolio). Geologic and diagenetic history, industrial preparation methods, and the specific combustion process all play major roles in the composition of CUB. During combustion, inorganic mineral phases of coal particles are fluidized at temperatures higher than 1400oC, so inorganic mineral materials are oxidized, fused, disintegrated, or agglomerated into larger spherical and amorphous (non-crystalline) particles. The original mineralogy of the coal-containing rock and heating/cooling of the material significantly affects the composition and morphology of the particles in the combustion byproduct (Kutchko and Kim, 2006). Thus, different types of coal/refuse/ash must be characterized to better understand mineral evolution during the combustion process. Our research focused on developing a working model to address how REE minerals behave during the combustion process: this research should help determine the most effective engineering methods for extracting REEs from CUBs. We used multimodal imaging and image processing techniques to characterize six rock and ash samples from different coal power plants with respect to morphology, grain size, presence of mineral phases, and elemental composition. The results of these characterization activities provided thresholds for realizing the occurrence of REE mineral phases in CUB and allowed us to calculate structural and volumetric estimates of REE. Collectively, the rock and coal ash samples contained minerals such as quartz, kaolinite, muscovite/illite, iron oxide (as hematite or magnetite), mullite, and clinochlore. Trace minerals included pyrite, zircon, siderite, rutile, diopside, foresterite, gypsum, and barite. We identified REE phosphate minerals monazite (Ce,La,Nd,Th)(PO 4,SiO 4), xenotime (YPO 4,SiO 4), and apatite (Ca 5(PO 4) 3(F,Cl,OH) via SEM and electron microprobe analysis: these materials generally occurred as 1-10 μm-long crystals in the rock and ash samples. As has been shown in other studies, amorphous material-aluminosilicate glass or iron oxyhydroxide-are the major components of coal fly and bottom ash. Trace amounts of amorphous calcium oxide and mixed element (e.g., Al-Si-Ca-Fe) slag are also present. Quartz, mullite, hematite, and magnetite are the crystalline phases present. We found that REEs are present as monomineralic grains dispersed within the ash, as well as fused to or encapsulated by amorphous aluminosilicate glass particles. Monazite and xenotime have relatively high melting points (>1800 °C) compared to typical combustion temperatures; our observations indicate that the REE-phosphates, which presumably contribute a large percentage of REE to the bulk ash REE pool, as measured by mass spectroscopy, are largely unaltered by the combustion. Our study shows that conventional coal combustion processes sequester REE minerals into aluminosilicate glass phases, which presents a new engineering challenge for extracting REE from coal ash. The characterization work summarized in this report provides a semi-quantitative assessments of REE in coal-containing rock and CUB. The data we obtained from 2- and 3-D imaging, elemental mapping, volumetric estimates, and advanced high-resolution pixel classification successfully identified the different mineral phases present in CUB. Further, our characterization results can guide techniques for extracting REEs from CUB, or other geologic and engineered materials. Whilst, interpretations will inform future REE separation and extraction techniques and technologies practical for commercial utilization of combustion byproducts generated by power plants.« less

Development and testing of synthetic RIPRAP constructed from coal combustion products.

DOT National Transportation Integrated Search

2013-11-01

Even with an increase in the amount of CCPs used in concrete construction, soil stabilization, and other applications, the coal power : industry must dispose of a significant amount of fly ash and bottom ash. One potential avenue for the material is ...

PEER REVIEW SUPPORTING THE STANDARDS FOR THE ...

EPA Pesticide Factsheets

EPA has been working on developing risk assessments to assist regulators, industry, and the public in evaluating the environmental risks associated with Fossil Fuel Combustion Waste(s) (FFCW) management/disposal in landfills, surface impoundments, other disposal procedures and beneficial uses. The U.S. Environmental Protection Agency (EPA) is evaluating management options for solid wastes from coal combustion (e.g., fly ash, bottom ash, slag). As part of this effort, EPA has prepared the Draft Human and Ecological Risk Assessment of Coal Combustion Wastes. The purpose of this draft risk assessment is to identify and quantify human health and ecological risks that may be associated with current disposal practices for high-volume coal combustion waste (CCW), including fly ash, bottom ash, boiler slag, flue gas desulfurization (FGD) sludge, coal refuse waste, and wastes from fluidized-bed combustion (FBC) units. These risk estimates will help inform EPA’s decisions about how to treat CCW under Subtitle D of the Resource Conservation and Recovery Act.

Mineralogy of ash of some American coals: variations with temperature and source

USGS Publications Warehouse

Mitchell, R.S.; Gluskoter, H.J.

1976-01-01

Ten samples of mineral-matter residue were obtained by the radio-frequency low-temperature ashing of subbituminous and bituminous coals. The low-temperature ash samples were then heated progressively from 400 ??C to 1400 ??C at 100 ??C intervals. Mineral phases present at each temperature interval were determined by X-ray diffraction analyses. The minerals originally present in the coals (quartz, kaolinite, illite, pyrite, calcite, gypsum, dolomite, and sphalerite) were all altered to higher temperature phases. Several of these phases, including kaolinite, metakaolinite, mullite, anhydrite, and anorthite, were found only in limited temperature ranges. Therefore the temperature of formation of the ashes in which they occur may be determined. Mineralogical differences were observed between coal samples from the Rocky Mountain Province, the Illinois Basin, and the Appalachians; and as a result of these mineralogical differences, different high-temperature phases resulted as the samples were heated. However, regional generalizations cannot be made until a greater number of samples have been studied. ?? 1976.

Firing system modification to alter ash properties for reduction of deposition and slagging under low NOx firing conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hart, D.; Lewis, R.; Tobiasz, R.

1998-07-01

The composition and properties of ash formed during coal firing have a major impact on boiler performance. Higher ash content in the coal can mean higher costs associated with coal handling, transportation, ash removal and ash disposal along with higher costs due to the increased ash content's deleterious effects on pulverizing, combustion and heat transfer. ABB C-E Services, Inc. has conducted research what might be done to minimize the adverse effects of ash on boiler performance for many years. Recently, ABB C-E Services has studied the effects of firing system modifications on ash composition and properties and the effect thesemore » firing system modifications have on overall furnace performance. The subject of this paper is the impact of the installation of the CFS{trademark} yaw angles were varied and particle samples were collected at the waterwalls for the different yaw angles tested. These ash samples were analyzed for ash composition. The results showed that with a larger CFS{trademark} yaw angle (the air stream directed more towards the boiler walls) the base/acid ratio, iron content and sulfur content of the particle samples collected at the waterwall were reduced. This effect is due to several contributing factors: (1) an oxidizing environment produced by injecting more air toward the walls; and (2) an aerodynamic change which impacts the particle combustion time/temperature history.« less

Chemical and engineering properties of fired bricks containing 50 weight percent of class F fly ash

USGS Publications Warehouse

Chou, I.-Ming; Patel, V.; Laird, C.J.; Ho, K.K.

2001-01-01

The generation of fly ash during coal combustion represents a considerable solid waste disposal problem in the state of Illinois and nationwide. In fact, the majority of the three million tons of fly ash produced from burning Illinois bituminous coals is disposed of in landfills. The purpose of this study was to obtain a preliminary assessment of the technical feasibility of mitigating this solid waste problem by making fired bricks with the large volume of fly ash generated from burning Illinois coals. Test bricks were produced by the extrusion method with increasing amounts (20-50% by weight) of fly ash as a replacement for conventional raw materials. The chemical characteristics and engineering properties of the test bricks produced with and without 50 wt% of fly ash substitutions were analyzed and compared. The properties of the test bricks containing fly ash were at least comparable to, if not better than, those of standard test bricks made without fly ash and met the commercial specifications for fired bricks. The positive results of this study suggest that further study on test bricks with fly ash substitutions of greater than 50wt% is warranted. Successful results could have an important impact in reducing the waste disposal problem related to class F fly ash while providing the brick industry with a new low cost raw material. Copyright ?? 2001 Taylor & Francis.

Preparation of sintered foam materials by alkali-activated coal fly ash.

PubMed

Zhao, Yelong; Ye, Junwei; Lu, Xiaobin; Liu, Mangang; Lin, Yuan; Gong, Weitao; Ning, Guiling

2010-02-15

Coal fly ash from coal fired power stations is a potential raw material for the production of ceramic tiles, bricks and blocks. Previous works have demonstrated that coal fly ash consists mainly of glassy spheres that are relatively resistant to reaction. An objective of this research was to investigate the effect of alkali on the preparation process of the foam material. Moreover, the influence of foam dosage on the water absorption, apparent density and compressive strength was evaluated. The experimental results showed that homogenous microstructures of interconnected pores could be obtained by adding 13 wt.% foaming agent at 1050 degrees C, leading to foams presenting water absorption, apparent density and compressive strength values of about 126.5%, 0.414 g/cm(3), 6.76 MPa, respectively.

Inhalation health effects of fine particles from the co-combustion of coal and refuse derived fuel.

PubMed

Fernandez, Art; Wendt, Jost O L; Wolski, Natacha; Hein, Klaus R G; Wang, Shengjun; Witten, Mark L

2003-06-01

This paper is concerned with health effects from the inhalation of particulate matter (PM) emitted from the combustion of coal, and from the co-combustion of refuse derived fuel (RDF) and pulverized coal mixtures, under both normal and low NO(x) conditions. Specific issues focus on whether the addition of RDF to coal has an effect on PM toxicity, and whether the application of staged combustion (for low NO(x)) may also be a factor in this regard. Ash particles were sampled and collected from a pilot scale combustion unit and then re-suspended and diluted to concentrations of approximately 1000 microg/m(3). These particles were inhaled by mice, which were held in a nose-only exposure configuration. Exposure tests were for 1 h per day, and involved three sets (eight mice per set) of mice. These three sets were exposed over 8, 16, and 24 consecutive days, respectively. Pathological lung damage was measured in terms of increases in lung permeability. Results show that the re-suspended coal/RDF ash appeared to cause very different effects on lung permeability than did coal ash alone. In addition, it was also shown that a "snapshot" of lung properties after a fixed number of daily 1-h exposures, can be misleading, since apparent repair mechanisms cause lung properties to change over a period of time. For the coal/RDF, the greatest lung damage (in terms of lung permeability increase) occurred at the short exposure period of 8 days, and thereafter appeared to be gradually repaired. Ash from staged (low NO(x)) combustion of coal/RDF appeared to cause greater lung injury than that from unstaged (high NO(x)) coal/RDF combustion, although the temporal behavior and (apparent) repair processes in each case were similar. In contrast to this, coal ash alone showed a slight decrease of lung permeability after 1 and 3 days, and this disappeared after 12 days. These observations are interpreted in the light of mechanisms proposed in the literature. The results all suggest that the composition of particles actually inhaled is important in determining lung injury. Particle size segregated leachability measurements showed that water soluble sulfur, zinc, and vanadium, but not iron, were present in the coal/RDF ash particles, which caused lung permeabilities to increase. However, the differences in health effects between unstaged and staged coal/RDF combustion could not be attributed to variations in pH values of the leachate.

Environmental impact of coal ash on tributary streams and nearshore waters of Lake Erie. Quarterly reports, August 31 and November 30, 1975, combined. [Cd, Zn, Cu, Fe, Mn, Cr, Ca, K, Mg, Na, Pb, As, Se

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The study of coal wastes in Chautauga County, New York was begun on June 1, 1975. The major effort to date has been made on the fly ash dump west of Dunkirk, N.Y. The following topics are covered: description of the site; invertebrate biology; selection of trace elements for study and methods of analysis; water analyses; analyses of invertebrates; literature search; physical chemistry of coal ash and the leaching process; and study of lake sediments.

Prospects for the development of coal-steam plants in Russia

NASA Astrophysics Data System (ADS)

Tumanovskii, A. G.

2017-06-01

Evaluation of the technical state of the modern coal-fired power plants and quality of coal consumed by Russian thermal power plants (TPP) is provided. Measures aimed at improving the economic and environmental performance of operating 150-800 MW coal power units are considered. Ways of efficient use of technical methods of NO x control and electrostatic precipitators' upgrade for improving the efficiency of ash trapping are summarized. Examples of turbine and boiler equipment efficiency upgrading through its deep modernization are presented. The necessity of the development and introduction of new technologies in the coal-fired power industry is shown. Basic technical requirements for a 660-800 MW power unit with the steam conditions of 28 MPa, 600/600°C are listed. Design solutions taking into account features of Russian coal combustion are considered. A field of application of circulating fluidized bed (CFB) boilers and their effectiveness are indicated. The results of development of a new generation coal-fired TPP, including a steam turbine with an increased efficiency of the compartments and disengaging clutch, an elevated steam conditions boiler, and a highly efficient NO x /SO2 and ash particles emission control system are provided. In this case, the resulting ash and slag are not to be sent to the ash dumps and are to be used to a maximum advantage. Technical solutions to improve the efficiency of coal gasification combined cycle plants (CCP) are considered. A trial plant based on a 16 MW gas turbine plant (GTP) and an air-blown gasifier is designed as a prototype of a high-power CCP. The necessity of a state-supported technical reequipment and development program of operating coal-fired power units, as well as putting into production of new generation coal-fired power plants, is noted.

Behavior of fluorine and chlorine in Spanish coal fired power plants with pulverized coal boilers and fluidized bed boiler.

PubMed

López-Vilariño, J M; Fernández-Martínez, G; Turnes-Carou, I; Muinategui-Lorenzo, S; López-Mahía, P; Prada-Rodríguez, D

2003-06-01

Behavior and contents of fluorine and chlorine in coal feedstock, combustion wastes (slag and fly ash) and emissions were studied in five conventional coal fired power plants and in a fluidized bed coal power plant. The halide levels found in the used coal were quite low. Mass balances and emission factors were calculated. The volatility of these elements makes the gaseous emission the main target between the residues. The influence of combustion parameters is not clearly established. Several analytical techniques (ion selective electrodes, capillary electrophoresis and ion chromatography) are employed to determinate the halide concentration in the different samples taken in the power plants studied (coal, slag, fly ash and flue gases).

Proceedings of Office of Surface Mining Coal Combustion By-product Government/Regulatory Panel: University of Kentucky international ash utilization symposium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vories, K.C.

2003-07-01

Short papers are given on: the Coal Combustion Program (C2P2) (J. Glenn); regional environmental concerns with disposal of coal combustion wastes at mines (T. FitzGerald); power plant waste mine filling - an environmental perspective (L.G. Evans); utility industry perspective regarding coal combustion product management and regulation (J. Roewer); coal combustion products opportunities for beneficial use (D.C. Goss); state perspective on mine placement of coal combustion by-products (G.E. Conrad); Texas regulations provide for beneficial use of coal combustion ash (S.S. Ferguson); and the Surface Mining Control and Reclamation Act - a response to concerns about placement of CCBs at coal minemore » sites (K.C. Vories). The questions and answers are also included.« less

One-Pot Synthesis of GeAs Ultrafine Particles from Coal Fly Ash by Vacuum Dynamic Flash Reduction and Inert Gas Condensation.

PubMed

Zhang, Lingen; Xu, Zhenming

2017-06-16

Ge-monopnictides (GeAs) plays critical role in high-tech industry, especially in the field of advanced optical devices and infrared. As a secondary material, coal fly ash could be further recycled to retrieve germanium and prepare GeAs material with high added values. Hence, the aim of this paper is to propose a one-pot synthesis that uses vacuum flash reduction and inert-gas consolidation method to prepare GeAs ultrafine particles. Germanium in coal fly ash can be successfully recycled; simultaneously, GeAs ultrafine particles were prepared. Separation principle and feasibility of this process was discussed. Temperature, carrier gas flow rate and system pressure were the major factors on formation, morphology and distribution of particle size of GeAs ultrafine particles. A three steps synthetic mechanism was clarified, namely, thermal rupture of coal fly ash and release of GeO 2 and As 2 O 3 , the gas-solid phase reaction of GeO 2 , As 2 O 3 and coke to generate metallic Ge and As in vacuum flash reduction. Meantime, GeAs were produced in the gas phase reaction. Finally, GeAs ultrafine particles were obtained by carrier gas condensation. In short, this research developed a practical and environment-friendly one-pot synthesis to recycle germanium in coal fly ash and prepare GeAs ultrafine particles with high added values.

Evidence of Coal-Fly-Ash Toxic Chemical Geoengineering in the Troposphere: Consequences for Public Health

PubMed Central

Herndon, J. Marvin

2015-01-01

The widespread, intentional and increasingly frequent chemical emplacement in the troposphere has gone unidentified and unremarked in the scientific literature for years. The author presents evidence that toxic coal combustion fly ash is the most likely aerosolized particulate sprayed by tanker-jets for geoengineering, weather-modification and climate-modification purposes and describes some of the multifold consequences on public health. Two methods are employed: (1) Comparison of 8 elements analyzed in rainwater, leached from aerosolized particulates, with corresponding elements leached into water from coal fly ash in published laboratory experiments, and (2) Comparison of 14 elements analyzed in dust collected outdoors on a high-efficiency particulate air (HEPA) filter with corresponding elements analyzed in un-leached coal fly ash material. The results show: (1) the assemblage of elements in rainwater and in the corresponding experimental leachate are essentially identical. At a 99% confidence interval, they have identical means (T-test) and identical variances (F-test); and (2) the assemblage of elements in the HEPA dust and in the corresponding average un-leached coal fly ash are likewise essentially identical. The consequences on public health are profound, including exposure to a variety of toxic heavy metals, radioactive elements, and neurologically-implicated chemically mobile aluminum released by body moisture in situ after inhalation or through transdermal induction. PMID:26270671

A commitment to coal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shea, Q.

2006-07-15

Quin Shea explores the need for power generated with coal and the advanced technologies that will generate that power more efficiently and cleanly in the future. The article considers the air and waste challenges of using coal, including progress toward reducing emissions of SO{sub 2}, NOx, and mercury; efforts to address CO{sub 2}, including voluntary programs like the Climate Challenge, Power Partners, and the Asia-Pacific Partnership on Clean Development and Climate; and the regulation and beneficial use of coal-combustion byproducts (e.g., fly ash, bottom ash, flue gas desulfurization materials, boiler slag). 17 refs.

Firing system modification to alter ash properties for reduction of deposition and slagging under low NOx firing conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hart, D.; Lewis, R.; Tobiasz, R.

1998-12-31

The composition and properties of ash formed during coal firing have a major impact on boiler performance. Higher ash content in the coal can mean higher costs associated with coal handling, transportation, ash removal and ash disposal along with higher costs due to the increased ash content`s deleterious effects on pulverizing, combustion and heat transfer. ABB C-E Services, Inc. has conducted research for many years on what might be done to minimize the adverse effects of ash on boiler performance. Recently, ABB C-E Services has studied the effects of firing system modifications on ash composition and properties and the effectmore » these firing system modifications have on overall furnace performance. The subject of this paper is the impact of the installation of the CFS Concentric Firing System on the propensity for boiler wall ash deposition. For this study, CFS yaw angles were varied and particle samples were collected at the waterwalls for the different yaw angles tested. These ash samples were analyzed for ash composition. The results showed that with a larger CFS yaw angle (the air stream directed more towards the boiler walls) the base/acid ratio, iron content and sulfur content of the particle samples collected at the waterwall were reduced. This effect is due to several contributing factors: (1) an oxidizing environment produced by injecting more air toward the walls; and (2) an aerodynamic change which impacts the particle combustion time/temperature history.« less

Characterization of the chemical variation of feed coal and coal combustion products from a power plant utilizing low sulfur Powder River Basin coal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Affolter, R.H.; Brownfield, M.E.; Cathcart, J.D.

2000-07-01

The US Geological Survey and the University of Kentucky Center for Applied Energy Research, in collaboration with an Indiana utility, are studying a coal-fired power plant burning Powder River Basin coal. This investigation involves a systematic study of the chemical and mineralogical characteristics of feed coal and coal combustion products (CCPs) from a 1,300-megawatt (MW) power unit. The main goal of this study is to characterize the temporal chemical variability of the feed coal, fly ash, and bottom ash by looking at the major-, minor-, and trace-element compositions and their associations with the feed coal mineralogy. Emphasis is also placedmore » on the abundance and modes of occurrence of elements of potential environmental concern that may affect the utilization of these CCPs and coals.« less

Regeneratively cooled coal combustor/gasifier with integral dry ash removal

DOEpatents

Beaufrere, A.H.

1982-04-30

A coal combustor/gasifier is disclosed which produces a low or medium combustion gas fired furnances or boilers. Two concentric shells define a combustion air flows to provide regenerative cooling of the inner shell for dry ash operation. A fuel flow and a combustion air flow having opposed swirls are mixed and burned in a mixing-combustion portion of the combustion volume and the ash laden combustion products flow with a residual swirl into an ash separation region. The ash is cooled below the fusion temperature and is moved to the wall by centrifugal force where it is entrained in the cool wall boundary layer. The boundary layer is stabilized against ash re-entrainment as it is moved to an ash removal annulus by a flow of air from the plenum through slots in the inner shell, and by suction on an ash removal skimmer slot.

Improved leaching test methods for environmental assessment of coal ash and recycled materials used on construction

EPA Science Inventory

Changes in air pollution control at coal-fired power plants will result in lower emissions of mercury and other pollutants. Fly ash, flue gas desulfurization gypsum, and other air pollution control residues are used in agricultural, commercial, and engineering applications. Resea...

DESIGN AND CHARACTERIZATION OF AN ULTRAFINE COAL ASH AEROSOL GENERATOR FOR DIRECT ANIMAL EXPOSURE STUDIES

EPA Science Inventory

Primary ultrafine particulate matter (PM) is produced during pulverized coal combustion by the nucleation and heterogeneous condensation of vapor-phase species. This differs from the mechanisms that control the formation of the supermicron fly ash that is heavily influenced by t...

Chemical and physical characteristics of coal and carbonaceous shale samples from the Salt Range coal field, Punjab Province, Pakistan

USGS Publications Warehouse

Warwick, Peter D.; Shakoor, T.; Javed, Shahid; Mashhadi, S.T.A.; Hussain, H.; Anwar, M.; Ghaznavi, M.I.

1990-01-01

Sixty coal and carbonaceous shale samples collected from the Paleocene Patala Formation in the Salt Range coal field, Punjab Province, Pakistan, were analyzed to examine the relationships between coal bed chemical and physical characteristics and depositional environments. Results of proximate and ultimate analyses, reported on an as received basis, indicate that coal beds have an average ash yield of 24.23 percent, average sulfur content of 5.32 percent, average pyritic sulfur content of 4.07 percent, and average calorific value of 8943 Btu (4972 kcal/kg). Thirty five coal samples, analyzed on a whole coal, dry basis for selected trace elements and oxides, have anomalously high average concentrations of Ti, at O.3& percent; Zr, at 382 ppm; and Se, at 11.4 ppm, compared to world wide averages for these elements in coal.Some positive correlation coefficients, significant at a 0.01 level, are those between total sulfur and As, pyritic sulfur and As, total sulfur and sample location, organic sulfur and Se, calorific value (Btu) and sample location, and coal bed thickness and Se. Calorific values -for the samples, calculated on a moist, mineral matter free basis, indicate that the apparent rank of the coal is high volatile C bituminous.Variations observed in the chemical and physical characteristics of the coal beds may be related to depositional environments. Total ash yields and concentrations of Se and organic sulfur increase toward more landward depositional environments and may be related to an increase of fluvial influence on peat deposition. Variations in pyritic sulfur concentrations may be related to post-peat pyrite filled burrows commonly observed in the upper part of the coal bed. The thickest coal beds that have the lowest ash content, and highest calorific values, formed from peats deposited in back barrier, tidal flat environments of the central and western parts of the coal field. The reasons for correlations between Se and coal bed thickness and Se and ash content are not clear and may be a product of averaging.

Enrichment of naturally occurring radionuclides and trace elements in Yatagan and Yenikoy coal-fired thermal power plants, Turkey.

PubMed

Ozden, Banu; Guler, Erkan; Vaasma, Taavi; Horvath, Maria; Kiisk, Madis; Kovacs, Tibor

2018-08-01

Coal, residues and waste produced by the combustion of the coal contain naturally occurring radionuclides such as 238 U, 226 Ra, 210 Pb, 232 Th and 40 K and trace elements such as Cd, Cr, Pb, Ni and Zn. In this work, coal and its combustion residues collected from Yatagan and Yenikoy coal fired thermal power plants (CPPs) in Turkey were studied to determine the concentrations of natural radionuclides and trace elements, and their enrichments factors to better understand the radionuclide concentration processes within the combustion system. In addition, the utilization of coal fly ash as a secondary raw material in building industry was also studied in terms of radiological aspects. Fly ash samples were taken at different stages along the emission control system of the thermal power plants. Activity concentrations of naturally occurring radionuclides were determined with Canberra Broad Energy Germanium (BEGe) detector BE3830-P and ORTEC Soloist PIPS type semiconductor detector. The particle size distribution and trace elements contents were determined in various ash fractions by the laser scattering particle size distribution analyzer and inductively coupled plasma (ICP-OES). From the obtained data, natural radionuclides tend to condense on fly ash with and the activity concentrations increase as the temperature drop in CPPs. Measured 210 Pb and 210 Po concentration varied between 186 ± 20-1153 ± 44 Bq kg -1 , and 56 ± 5-1174 ± 45 Bq kg -1 , respectively. The highest 210 Pb and 210 Po activity concentrations were determined in fly ash taken from the temporary storage point as 1153 ± 44 Bq kg -1 and 1174 ± 45 Bq kg -1 , respectively. There were significant differences in the activity concentrations of some natural radionuclide and trace elements (Pb and Zn) contents in ash fractions among the sampling point inside both of the plants (ANOVA, p < 0.001). Coal and ash sample analysis showed an increase activity concentration and enrichment factors towards the electrostatic precipitators for both of the power plants. The enrichment factors for Zn follow a similar trend as Pb, increasing in value towards the end of the emission control system. The calculated activity indexes were above 1.0 value for both of the power plants, assuming the utilization of fly ash at 100%. It can be concluded that the reuse of fly ash as a secondary raw material may not be hazardous depending on the percentage of utilization of ash. Copyright © 2017 Elsevier Ltd. All rights reserved.

Kinetic modeling of the formation and growth of inorganic nano-particles during pulverized coal char combustion in O 2/N 2 and O 2/CO 2 atmospheres

DOE PAGES

Shaddix, Christopher R.; Niu, Yanqing; Hui, Shi'en; ...

2016-08-01

In this formation of nano-particles during coal char combustion, the vaporization of inorganic components in char and the subsequent homogeneous particle nucleation, heterogeneous condensation, coagulation, and coalescence play decisive roles. Furthermore, conventional measurements cannot provide detailed information on the dynamics of nano-particle formation and evolution, In this study, a sophisticated intrinsic char kinetics model that considers ash effects (including ash film formation, ash dilution, and ash vaporization acting in tandem), both oxidation and gasification by CO 2 and H 2O, homogeneous particle nucleation, heterogeneous vapor condensation, coagulation, and and coalescence mechanisms is developed and used to compare the temporal evolutionmore » of the number and size of nano-particles during coal char particle combustion as a function of char particle size, ash content, and oxygen content in O 2/N 2 and O 2/CO 2 atmospheres .« less

Kinetic modeling of the formation and growth of inorganic nano-particles during pulverized coal char combustion in O 2/N 2 and O 2/CO 2 atmospheres

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shaddix, Christopher R.; Niu, Yanqing; Hui, Shi'en

In this formation of nano-particles during coal char combustion, the vaporization of inorganic components in char and the subsequent homogeneous particle nucleation, heterogeneous condensation, coagulation, and coalescence play decisive roles. Furthermore, conventional measurements cannot provide detailed information on the dynamics of nano-particle formation and evolution, In this study, a sophisticated intrinsic char kinetics model that considers ash effects (including ash film formation, ash dilution, and ash vaporization acting in tandem), both oxidation and gasification by CO 2 and H 2O, homogeneous particle nucleation, heterogeneous vapor condensation, coagulation, and and coalescence mechanisms is developed and used to compare the temporal evolutionmore » of the number and size of nano-particles during coal char particle combustion as a function of char particle size, ash content, and oxygen content in O 2/N 2 and O 2/CO 2 atmospheres .« less

Effects of effluents from a coal-fired, electric-generating powerplant on local ground water near Hayden, Colorado

USGS Publications Warehouse

Ellis, S.R.; Mann, P.G.

1981-01-01

Data were collected at the Hayden, Colo., powerplant for about a year during 1978-79 to monitor the effects of effluent and raw-water storage ponds on the local ground water, Sage Creek, and the Yampa River. The concentration of boron in wells downgradient from the effluent ponds indicated that the ponds were leaking, increasing the average boron concentrations in the ground water to a level in excess of the standards for agricultural use of water. Water from seeps, probably the best indicators of downgradient water quality, had average concentrations of boron two times that of the Colorado Department of Health (1977) standard for agricultural use of water. Chemical analyses of water from wells and the discharge weir downgradient from the raw-water storage ponds indicated these ponds are leaking. The effect of this leakage is that the water in wells downgradient from these ponds has a lower specific conductance and a lower boron concentration than the water in wells downgradient from the effluent ponds. The concentration of trace elements in the water from the wells and the discharge weir generally declined during the study, probably because the ground water was recovering from the effects of a plume from the raw-water pond previously used for fly-ash disposal. The effluents from the Hayden powerplant lowered the specific conductance and the iron and manganese concentrations, increased the concentration of boron, and had little or no effect on the selenium concentration in Sage Creek. Sage Creek had no discernible effect on the Yampa River because the volume of water in the Yampa River was so much greater. The effluents from the powerplant also had no discernible effect on the Yampa River. (USGS)

Recovery of iron oxide from coal fly ash

DOEpatents

Dobbins, Michael S.; Murtha, Marlyn J.

1983-05-31

A high quality iron oxide concentrate, suitable as a feed for blast and electric reduction furnaces is recovered from pulverized coal fly ash. The magnetic portion of the fly ash is separated and treated with a hot strong alkali solution which dissolves most of the silica and alumina in the fly ash, leaving a solid residue and forming a precipitate which is an acid soluble salt of aluminosilicate hydrate. The residue and precipitate are then treated with a strong mineral acid to dissolve the precipitate leaving a solid residue containing at least 90 weight percent iron oxide.

Impact of solid discharges from coal usage in the Southwest.

PubMed

Jones, D G; Straughan, I R

1978-12-01

The Southwestern region of the United States is extremely wealthy in low sulfur coal resources which must be eventually utilized in response to national energy balance priorities. Fly ash and scrubber sludge can be safely disposed of using properly managed techniques to ensure that any potential impact from elements such as boron, molybdenum, or selenium is rendered insignificant. Alternative methods of solids utilization are presently being developed. Fly ash is presently being marketed commercially as an additive for concrete manufacture. Successful experiments have been completed to demonstrate the manufacture of commercial-grade wallboard from scrubber sludge. Also, greenhouse studies and field experiments have been conducted to demonstrate increased yields of selected crops grown on typical soils amended with fly ash in amounts ranging from 2% to 8%, by weight. These studies also indicate that barium and strontium may be good monitoring indices for determining atmospheric deposition of fly ash, due to their concentration ratios in soil and vegetation samples. Further studies are being conducted to confirm encouraging irrigation and crop-yield data obtained with fly ash amended soils. Finally, the composition of many fly ashes and soils are similar in the Southwest, and there are no anticipated solid discharges from coal usage which cannot be rendered insignificant with proper management of existing and emerging methods of treatment. Compared with the water availability impact of coal usage in the Southwest, the impact of solid waste discharges are insignificant.

Combustion characteristics and arsenic retention during co-combustion of agricultural biomass and bituminous coal.

PubMed

Zhou, Chuncai; Liu, Guijian; Wang, Xudong; Qi, Cuicui; Hu, Yunhu

2016-08-01

A combination of thermogravimetric analysis (TG) and laboratory-scale circulated fluidized bed combustion experiment was conducted to investigate the thermochemical, kinetic and arsenic retention behavior during co-combustion bituminous coal with typical agricultural biomass. Results shown that ignition performance and thermal reactivity of coal could be enhanced by adding biomass in suitable proportion. Arsenic was enriched in fly ash and associated with fine particles during combustion of coal/biomass blends. The emission of arsenic decreased with increasing proportion of biomass in blends. The retention of arsenic may be attributed to the interaction between arsenic and fly ash components. The positive correlation between calcium content and arsenic concentration in ash suggesting that the arsenic-calcium interaction may be regarded as the primary mechanism for arsenic retention. Copyright © 2016 Elsevier Ltd. All rights reserved.

Integrated Waste Treatment Unit (IWTU) Input Coal Analyses and Off-Gass Filter (OGF) Content Analyses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jantzen, Carol M.; Missimer, David M.; Guenther, Chris P.

A full engineering scale Fluidized Bed Steam Reformer (FBSR) system is being used at the Idaho Nuclear Technology and Engineering Center (INTEC) to stabilize acidic Low Activity Waste (LAW) known as Sodium Bearing Waste (SBW). The INTEC facility, known as the Integrated Waste Treatment Unit (IWTU), underwent an Operational Readiness Review (ORR) and a Technology Readiness Assessment (TRA) in March 2014. The IWTU began non-radioactive simulant processing in late 2014 and by January, 2015 ; the IWTU had processed 62,000 gallons of simulant. The facility is currently in a planned outage for inspection of the equipment and will resume processingmore » simulated waste feed before commencing to process 900,000 gallons of radioactive SBW. The SBW acidic waste will be made into a granular FBSR product (carbonate based) for disposal in the Waste Isolation Pilot Plant (WIPP). In the FBSR process calcined coal is used to create a CO2 fugacity to force the waste species to convert to carbonate species. The quality of the coal, which is a feed input, is important because the reactivity, moisture, and volatiles (C,H,N,O, and S) in the coal impact the reactions and control of the mineralizing process in the primary steam reforming vessel, the Denitration and Mineralizing Reformer (DMR). Too much moisture in the coal can require that additional coal be used. However since moisture in the coal is only a small fraction of the moisture from the fluidizing steam this can be self-correcting. If the coal reactivity or heating value is too low then the coal feedrate needs to be adjusted to achieve the desired heat generation. Too little coal and autothermal heat generation in the DMR cannot be sustained and/or the carbon dioxide fugacity will be too low to create the desired carbonate mineral species. Too much coal and excess S and hydroxide species can form. Excess sulfur from coal that (1) is too rich in sulfur or (2) from overfeeding coal can promote wall scale and contribute to corrosion in process piping and materials, in excessive off-gas absorbent loading, and in undesired process emissions. The ash content of the coal is important as the ash adds to the DMR and other vessel products which affect the final waste product mass and composition. The amount and composition of the ash also affects the reaction kinetics. Thus ash content and composition contributes to the mass balance. In addition, sodium, potassium, calcium, sulfur, and maybe silica and alumina in the ash may contribute to wall-scale formation. Sodium, potassium, and alumina in the ash will be overwhelmed by the sodium, potassium, and alumina from the feed but the impact from the other ash components needs to be quantified. A maximum coal particle size is specified so the feed system does not plug and a minimum particle size is specified to prevent excess elutriation from the DMR to the Process Gas Filter (PGF). A vendor specification was used to procure the calcined coal for IWTU processing. While the vendor supplied a composite analysis for the 22 tons of coal (Appendix A), this study compares independent analyses of the coal performed at the Savannah River National Laboratory (SRNL) and at the National Energy Technology Laboratory (NETL). Three supersacks a were sampled at three different heights within the sack in order to determine within bag variability and between bag variability of the coal. These analyses were also compared to the vendor’s composite analyses and to the coal specification. These analyses were also compared to historic data on Bestac coal analyses that had been performed at Hazen Research Inc. (HRI) between 2004-2011.« less

Low ash, planar peat swamp development in an alluvial plain setting: The No. 5 block beds of southern West Virginia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Staub, J.R.; Richards, B.K.

1992-01-01

Coals from the No. 5 Block beds (Westphalian D) are noted for their low ash and sulfur content. Beds are multiple benched, with rock partings separating individual benches. Benches have limited continuity and, where thick are dominated by bright, high ash coal at the base and dull, low ash coal in their upper portions. The duller coals contain more exinite and inertinite group macerals than the brighter coals. The depositional setting is an alluvial plain environment with channel systems separated by distances of about 20 km. The channel systems were flanked by clastic swamps for distances of up to 7more » km or more on either side. Areas of flood plain most distant from the channels were sites where peat accumulated and these zones were about 8 km across. High energy, low frequency flood events introduced fine grained sediment into the peat swamps resulting in thin layers of sediment being deposited on top of the peat. These sediment layers are thicker in areas where the underlying coal is the thickest. These thick coal areas are topographically negative. This relationship between coal and parting thickness and topography indicates that these peat swamps were low-lying or planar. Individual coal benches contain abundant amounts of preserved cellular tissue (telocollinite, semifusinite, fusinite) at most locations indicating that woody arborescent like vegetation was widespread in the swamps suggesting a planar morphology. The high concentrations of exinite and inertinite group macerals found in the upper portions of individual benches resulted from decomposition and oxidation of the peat in subaerial to aquatic planar swamp environments.« less

Coal-oil slurry preparation

DOEpatents

Tao, John C.

1983-01-01

A pumpable slurry of pulverized coal in a coal-derived hydrocarbon oil carrier which slurry is useful as a low-ash, low-sulfur clean fuel, is produced from a high sulfur-containing coal. The initial pulverized coal is separated by gravity differentiation into (1) a high density refuse fraction containing the major portion of non-coal mineral products and sulfur, (2) a lowest density fraction of low sulfur content and (3) a middlings fraction of intermediate sulfur and ash content. The refuse fraction (1) is gasified by partial combustion producing a crude gas product from which a hydrogen stream is separated for use in hydrogenative liquefaction of the middlings fraction (3). The lowest density fraction (2) is mixed with the liquefied coal product to provide the desired fuel slurry. Preferably there is also separately recovered from the coal liquefaction LPG and pipeline gas.

Application of LIBS and TMA for the determination of combustion predictive indices of coals and coal blends

NASA Astrophysics Data System (ADS)

Ctvrtnickova, T.; Mateo, M. P.; Yañez, A.; Nicolas, G.

2011-04-01

Presented work brings results of Laser-Induced Breakdown Spectroscopy (LIBS) and Thermo-Mechanical Analysis (TMA) of coals and coal blends used in coal fired power plants all over Spain. Several coal specimens, its blends and corresponding laboratory ash were analyzed by mentioned techniques and results were compared to standard laboratory methods. The indices of slagging, which predict the tendency of coal ash deposition on the boiler walls, were determined by means of standard chemical analysis, LIBS and TMA. The optimal coal suitable to be blended with the problematic national lignite coal was suggested in order to diminish the slagging problems. Used techniques were evaluated based on the precision, acquisition time, extension and quality of information they could provide. Finally, the applicability of LIBS and TMA to the successful calculation of slagging indices is discussed and their substitution of time-consuming and instrumentally difficult standard methods is considered.

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

The first part covers standards for gaseous fuels. The standard part covers standards on coal and coke including the classification of coals, determination of major elements in coal ash and trace elements in coal, metallurgical properties of coal and coke, methods of analysis of coal and coke, petrographic analysis of coal and coke, physical characteristics of coal, quality assurance and sampling.

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

The first part covers standards for gaseous fuels. The second part covers standards on coal and coke including the classification of coals, determination of major elements in coal ash and trace elements in coal, metallurgical properties of coal and coke, methods of analysis of coal and coke, petrogrpahic analysis of coal and coke, physical characteristics of coal, quality assurance and sampling.

Composition and trace element content of coal in Taiwan

USGS Publications Warehouse

Tsai, L.-Y.; Chen, C.-F.; Finkelman, R.B.

2005-01-01

To investigate the trace element contents of local coal, four coal samples were collected from operating mines in NW Taiwan. Detailed petrographic and chemical characterization analyses were then conducted. Analytical results indicate that (1) the samples were high volatile bituminous coal in rank with ash content ranging from 4.2 to 14.4% and with moisture content ranging from 2.7 to 4.6%; (2) the macerals were mostly composed of vitrinite with vitrinite reflectance less than 0.8%; (3) the sample of Wukeng mine has the highest Fe2O3 (29.5%), TI (54.8 ppm), Zn (140 ppm), and As (697 ppm) contents in ash and Hg (2.3 ppm) in the coal. If used properly, these coals should not present health hazards.

Effective use of fly ash slurry as fill material.

PubMed

Horiuchi, S; Kawaguchi, M; Yasuhara, K

2000-09-15

A lot of effort has been put into increasing coal ash utilization; however, 50% of total amount is disposed of on land and in the sea. Several attempts have been reported recently concerning slurried coal fly ash use for civil engineering materials, such as for structural fill and backfill. The authors have studied this issue for more than 15 years and reported its potential for (1) underwater fills, (2) light weight backfills, and (3) light weight structural fills, through both laboratory tests and construction works. This paper is an overview of the results obtained for slurry, focusing on the following. (1) Coal fly ash reclaimed by slurry placement shows lower compressibility, higher ground density, and higher strength than by the other methods. This higher strength increases stability against liquefaction during earthquake. (2) Higher stability of the fly ash ground formed by slurry placement is caused by higher density and its self-hardening property. (3) Stability of fly ash reclaimed ground can be increased by increasing density and also by strength enhancement by cement addition. (4) Technical data obtained through a man-made island construction project shows the advantages of fly ash slurry in terms of mechanical properties such as higher stability against sliding failure, sufficient ground strength, and also in terms of cost saving. (5) Concentration in leachates from the placed slurry is lower than the Japanese environmental law. (6) In order to enlarge the fly ash slurry application toward a lightweight fill, mixtures of air foam, cement and fly ash were examined. Test results shows sufficient durability of this material against creep failure. This material was then used as lightweight structural fill around a high-rise building, and showed sufficient quality. From the above data, it can be concluded that coal fly ash slurry can be effectively utilized in civil engineering projects.

EFFECT OF CONVENTIONAL AND ADVANCED COAL CONVERSION BY-PRODUCTS ON THE PULMONARY SYSTEM

EPA Science Inventory

To evaluate the environmental impact of different energy technologies, fly ash samples collected from a coal-fired and from an oil-fired electric power plant were used in aerosol inhalation exposures of mice. The effects of multiple 3-h exposures to the fly ash particles at 2 and...

The treatment of some low-rank coals with carbon dioxide water: Effects on slurry-relevant properties: Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Slegeir, W.; Sanchez, J.; Coughlan, R.

1986-09-01

This project is concerned with the results of employing CO/sub 2//H/sub 2/O treatments on two low-rank coals. The coals employed in this project were North Dakota lignite from the Indianhead Mine and Utah subbituminous from the Sufco mine. This project is concerned with changes in slurry-relevant characteristics for these low-rank coals due to such treatments. These characteristics include equilibrium moisture, ash content and composition, grindability and slurry rheology. Batch CO/sub 2//water treatments on North Dakota Indianhead lignite afforded a reduction in coal-bound moisture, affording as much as a 35% decrease in equilibrium moisture content. The resulting treated lignite also provedmore » to be a ''cleaner'' coal, with a 30 to 35% reduction in ash content. For the Utah Sufco coal, no appreciable changes in equilibrium moisture were attained and the ash contents generally only slightly reduced Sufco. However, for the more severe treatment, alkaline and alkaline earth were lowered appreciably, with a commensurate increase in ash fusion temperature. For both coals, some improvements in grindability were realized under the most severe treatment conditions (80/sup 0/C, 1200 psi). The less severe conditions afforded little changes in grindability. Some measurements taken of the rheology of treated -200 mesh Indianhead coal slurries have shown non-Newtonian behavior. These slurries settled rapidly when concentrations greater than 50% were reached, hence viscosity measurements were difficult to obtain. Although the mechanism of CO/sub 2//H/sub 2/O action on coal is not clear, the results of this project are consistent with an ion-exchange process, whereby the basic components are exchanged with the hydronium ion of the CO/sub 2//H/sub 2/O mixture. Such ion exchange may lead to other changes in the coal matrix. 38 refs., 8 figs, 18 tabs.« less

Immersion Freezing of Coal Combustion Ash Particles from the Texas Panhandle

NASA Astrophysics Data System (ADS)

Whiteside, C. L.; Tobo, Y.; Mulamba, O.; Brooks, S. D.; Mirrielees, J.; Hiranuma, N.

2017-12-01

Coal combustion aerosol particles contribute to the concentrations of ice-nucleating particles (INPs) in the atmosphere. Especially, immersion freezing can be considered as one of the most important mechanisms for INP formation in supercooled tropospheric clouds that exist at temperatures between 0°C and -38°C. The U.S. contains more than 550 operating coal-burning plants consuming 7.2 x 108 metric tons of coal (in 2016) to generate a total annual electricity of >2 billion MW-h, resulting in the emission of at least 4.9 x 105 metric tons of PM10 (particulate matter smaller than 10 µm in diameter). In Texas alone, 19 combustion plants generate 0.15 billion MW-h electricity and >2.4 x 104 metric tons of PM10. Here we present the immersion freezing behavior of combustion fly ash and bottom ash particles collected in the Texas Panhandle region. Two types of particulate samples, namely <45 µm sieved bottom ash (B_Ash_TX_PH) and <45 µm sieved fly ash (F_Ash_TX_PH), were prepared. Afterwards, their immersion freezing abilities were measured using the Cryogenic Refrigerator Applied to Freezing Test (CRAFT) system covering the heterogeneous freezing temperature down to -30 °C. The results were generated and are reported through two metrics, frozen fraction, ffrozen(T), and ice nucleation active site density per unit mass, nm(T) as a function of temperature. Our preliminary results show that an onset increase in ffrozen(T) for B_Ash_TX_PH (ffrozen) occurred as high as at -15°C, whereas the onset for F_Ash_TX_PH is at -18°C. Secondly, B_Ash_TX_PH exhibited a higher nm(-20 °C) of 105 g-1 than that of F_Ash_TX_PH ( 5 x 103 g-1). On the other hand, previous studies on different combustion ash samples have reported that the opposite trend (i.e., ice nucleation efficiency of fly ash is greater than that of bottom ash; Grawe et al., 2016, ACP; Umo et al., 2015, ACP). We will discuss possible reasons for the observed differences. In addition, the results of complementary physico-chemical analyses via X-ray diffraction technique, Raman microscopy and scanning electron microscopy on both ash types will also be presented to relate the crystallographic and chemical properties to their ice nucleation abilities.

The use of tetragnathid spiders as bioindicators of metal exposure at a coal ash spill site.

PubMed

Otter, Ryan R; Hayden, Mary; Mathews, Teresa; Fortner, Allison; Bailey, Frank C

2013-09-01

On 22 December 2008, a dike containing coal fly ash from the Tennessee Valley Authority Kingston Fossil Fuel Plant (TN, USA) failed, resulting in the largest coal ash spill in US history. The present study was designed to determine sediment metal concentrations at multiple site locations and to determine whether site-specific bioaccumulation of metals existed in tetragnathid spiders. Selenium and nickel were the only 2 metals to exceed the US Environmental Protection Agency sediment screening levels. Selenium concentrations in spiders were significantly higher at ash-affected sites than in those from reference sites. The ratio of methylmercury to total mercury in spiders was found to be similar to that in other organisms (65-75%), which highlights the potential use of tetragnathid spiders as an indicator species for tracing contaminant transfer between the aquatic and terrestrial ecosystems. Copyright © 2013 SETAC.

Relationship between Particle Size Distribution of Low-Rank Pulverized Coal and Power Plant Performance

DOE PAGES

Ganguli, Rajive; Bandopadhyay, Sukumar

2012-01-01

Tmore » he impact of particle size distribution (PSD) of pulverized, low rank high volatile content Alaska coal on combustion related power plant performance was studied in a series of field scale tests. Performance was gauged through efficiency (ratio of megawatt generated to energy consumed as coal), emissions (SO 2 , NO x , CO), and carbon content of ash (fly ash and bottom ash). he study revealed that the tested coal could be burned at a grind as coarse as 50% passing 76 microns, with no deleterious impact on power generation and emissions. he PSD’s tested in this study were in the range of 41 to 81 percent passing 76 microns. here was negligible correlation between PSD and the followings factors: efficiency, SO 2 , NO x , and CO. Additionally, two tests where stack mercury (Hg) data was collected, did not demonstrate any real difference in Hg emissions with PSD. he results from the field tests positively impacts pulverized coal power plants that burn low rank high volatile content coals (such as Powder River Basin coal). hese plants can potentially reduce in-plant load by grinding the coal less (without impacting plant performance on emissions and efficiency) and thereby, increasing their marketability.« less

Analysis of eight argonne premium coal samples by X-ray fluorescence spectrometry

USGS Publications Warehouse

Evans, J.R.; Sellers, G.A.; Johnson, R.G.; Vivit, D.V.; Kent, J.

1990-01-01

X-ray fluorescence spectrometric methods were used in the analysis of eight Argonne Premium Coal Samples. Trace elements (Cr, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, La, and Ce) in coal ash were determined by energy-dispersive X-ray fluorescence spectrometry; major elements (Na, Mg, Al, Si, P, S, K, Ca, Ti, Mn, and Fe) in coal ash and trace elements (Cl and P) in whole coal were determined by wavelength-dispersive X-ray fluorescence spectrometry. The results of this study will be used in a geochemical database compiled for these materials from various analytical techniques. The experimental XRF methods and procedures used to determine these major and trace elements are described.

Flue gas desulfurization gypsum and fly ash

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1992-05-01

The Cumberland Fossil Plant (CUF) is located in Stewart County, Tennessee, and began commercial operation in 1972. This is the Tennessee Valley Authority`s newest fossil (coal-burning) steam electric generating plant. Under current operating conditions, the plant burns approximately seven million tons of coal annually. By-products from the combustion of coal are fly ash, approximately 428,000 tons annually, and bottom ash, approximately 115,000 tons annually. Based on historical load and projected ash production rates, a study was initially undertaken to identify feasible alternatives for marketing, utilization and disposal of ash by-products. The preferred alternative to ensure that facilities are planned formore » all by-products which will potentially be generated at CUF is to plan facilities to handle wet FGD gypsum and dry fly ash. A number of different sites were evaluated for their suitability for development as FGD gypsum and ash storage facilities. LAW Engineering was contracted to conduct onsite explorations of sites to develop information on the general mature of subsurface soil, rock and groundwater conditions in the site areas. Surveys were also conducted on each site to assess the presence of endangered and threatened species, wetlands and floodplains, archaeological and cultural resources, prime farmland and other site characteristics which must be considered from an environmental perspective.« less

Removal of cadmium from aqueous solutions using industrial coal fly ash-nZVI.

PubMed

Ma, Lixia; Wei, Qi; Chen, Yueqin; Song, Qiuyang; Sun, Conghui; Wang, Zhiqiang; Wu, Guanghong

2018-02-01

Batch experiments were conducted to test the effects of various solution properties, such as pH, temperature, initial concentration and anoxic and aerobic atmosphere, on Cd removal by nanoscale zerovalent iron (nZVI) supported on industrial coal fly ash. Cd (II) could be removed by adsorption on fly ash-nZVI in a very short time (5 min) with high removal rates (greater than 99.9%) over a wide range of concentration (5-100 mg l -1 ). Cd (II) was physically adsorbed on the surface of fly ash-nZVI. The preparation of fly ash-nZVI can incorporate the use of waste media, making the overall adsorbent more removal efficient and low cost.

Removal of cadmium from aqueous solutions using industrial coal fly ash-nZVI

PubMed Central

Ma, Lixia; Wei, Qi; Chen, Yueqin; Song, Qiuyang; Sun, Conghui; Wang, Zhiqiang

2018-01-01

Batch experiments were conducted to test the effects of various solution properties, such as pH, temperature, initial concentration and anoxic and aerobic atmosphere, on Cd removal by nanoscale zerovalent iron (nZVI) supported on industrial coal fly ash. Cd (II) could be removed by adsorption on fly ash-nZVI in a very short time (5 min) with high removal rates (greater than 99.9%) over a wide range of concentration (5–100 mg l−1). Cd (II) was physically adsorbed on the surface of fly ash-nZVI. The preparation of fly ash-nZVI can incorporate the use of waste media, making the overall adsorbent more removal efficient and low cost. PMID:29515830

Characterizations of coal fly ash nanoparticles and induced in vitro toxicity in cell lines

NASA Astrophysics Data System (ADS)

Sambandam, Bharathi; Palanisami, Eganathan; Abbugounder, Rajasekar; Prakhya, Balakrishnamurthy; Thiyagarajan, Devasena

2014-02-01

The present study illustrates the characterization and cytotoxicity studies of coal fly ash nanoparticles (CFA-NPs). The coal fly ash (CFA) collected from electrostatic precipitator of a coal-fired power plant and the average size of the CFA-NPs was found to be 9-50 nm. Imaging techniques showed predominantly homogenous spherical shaped nanoparticles. The X-ray diffraction analysis and energy dispersive X-ray (EDAX) analysis spectra reveal the elemental constituents of the CFA-NPs contain several toxic heavy metals. Cytotoxicity of CFA-NPs was determined by MTT assay. Cellular metabolism is inhibited in a dose dependent manner by CFA concentrations varying from 13 to 800 μg mL-1. After 48 h exposure, the Hep2, A549 and HepG2 cell lines prove more sensitive to CFA-NPs at varying levels which results in IC50 (50 % inhibitory concentration) cytotoxicity end point.

Study on emission of hazardous trace elements in a 350 MW coal-fired power plant. Part 2. arsenic, chromium, barium, manganese, lead.

PubMed

Zhao, Shilin; Duan, Yufeng; Chen, Lei; Li, Yaning; Yao, Ting; Liu, Shuai; Liu, Meng; Lu, Jianhong

2017-07-01

Hazardous Trace elements (HTEs) emitted from coal combustion has raised widespread concern. Studies on the emission characteristics of five HTEs, namely arsenic (As), chromium (Cr), barium (Ba), manganese (Mn), lead (Pb) at three different loads (100%, 83%, 71% output) and different coal types were performed on a 350 MW coal-fired power plant equipped with SCR, ESP + FF, and WFGD. HTEs in the flue gas at the inlet/outlet of each air pollution control device (APCD) were sampled simultaneously based on US EPA Method 29. During flue gas HTEs sampling, coal, bottom ash, fly ash captured by ESP + FF, fresh desulfurization slurry, desulfurization wastewater were also collected. Results show that mass balance rate for the system and each APCD is in an acceptable range. The five studied HTEs mainly distribute in bottom and ESP + FF ash. ESP + FF have high removal efficiency of 99.75-99.95%. WFGD can remove part of HTEs further. Total removal rate across the APCDs ranges from 99.84 to 99.99%. Concentration of HTEs emitted to atmosphere is within the extremely low scope of 0.11-4.93 μg/m 3 . Emission factor of the five studied HTEs is 0.04-1.54 g/10 12 J. Content of As, Pb, Ba, Cr in solid samples follows the order of ESP + FF ash > bottom ash > gypsum. More focus should be placed on Mn in desulfuration wastewater, content of which is more than the standard value. This work is meaningful for the prediction and removal of HTEs emitted from coal-fired power plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

Properties and Leachability of Self-Compacting Concrete Incorporated with Fly Ash and Bottom Ash

NASA Astrophysics Data System (ADS)

Kadir, Aeslina Abdul; Ikhmal Haqeem Hassan, Mohd; Jamaluddin, Norwati; Bakri Abdullah, Mohd Mustafa Al

2016-06-01

The process of combustion in coal-fired power plant generates ashes, namely fly ash and bottom ash. Besides, coal ash produced from coal combustion contains heavy metals within their compositions. These metals are toxic to the environment as well as to human health. Fortunately, treatment methods are available for these ashes, and the use of fly ash and bottom ash in the concrete mix is one of the few. Therefore, an experimental program was carried out to study the properties and determine the leachability of selfcompacting concrete incorporated with fly ash and bottom ash. For experimental study, self-compacting concrete was produced with fly ash as a replacement for Ordinary Portland Cement and bottom ash as a replacement for sand with the ratios of 10%, 20%, and 30% respectively. The fresh properties tests conducted were slump flow, t500, sieve segregation and J-ring. Meanwhile for the hardened properties, density, compressive strength and water absorption test were performed. The samples were then crushed to be extracted using Toxicity Characteristic Leaching Procedure and heavy metals content within the samples were identified accordingly using Atomic Absorption Spectrometry. The results demonstrated that both fresh and hardened properties were qualified to categorize as self-compacting concrete. Improvements in compressive strength were observed, and densities for all the samples were identified as a normal weight concrete with ranges between 2000 kg/m3 to 2600 kg/m3. Other than that, it was found that incorporation up to 30% of the ashes was safe as the leached heavy metals concentration did not exceed the regulatory levels, except for arsenic. In conclusion, this study will serve as a reference which suggests that fly ash and bottom ash are widely applicable in concrete technology, and its incorporation in self-compacting concrete constitutes a potential means of adding value to appropriate mix and design.

Coal Ash Aerosol in East Asian Outflow as a Source for Oceanic Deposition of Iron and Other Metals

NASA Astrophysics Data System (ADS)

Anderson, J. R.; Hua, X.

2008-12-01

While ocean deposition of East Asian dust is given significant emphasis as a source of biologically-active trace elements, iron in particular, dust events are episodic and highly seasonal. There is, however, a constant source of aerosol that is chemically similar to dust (albeit amorphous in structure rather than crystalline) in the ash particles emitted from many hundreds of coal-fired power plants that are sited along the entire coastal region of China and Korea. The emission controls on these facilities vary widely and, in even cases of state-of-the-art emission controls, the secondary release of ash can be significant. There are of course even more small industrial and household sources of coal combustion emissions, in most cases with little or no emissions controls. Ash from a modern coal-fired power facility in Korea has been examined chemically and morphologically with electron microscopic techniques. As is characteristic of all such facilities, two principal types of ash are present: (1) flyash, silicate glass spheres that are emitted with the smoke and removed by electrostatic precipitators; and (2) bottom ash, "clinkers" and noncombustible material sticking to the furnace walls that are mixed with water and ground after cooling, then removed as a slurry to a dumping area. In addition, iron sulfide (pyrite) is a common constituent of coal and provides both a source of sulfur dioxide gas and also molten iron spherical particles in the ash. The iron spheres then are rapidly oxidized upon cooling. Bottom ash is a more complex material than flyash in that it contains more iron and other trace metals, plus it contains varying amounts of uncombusted carbon. The post-combustion handling of bottom ash can lead to significant emissions despite the fact that little or none goes out the stack. The iron oxide spheres can also be emitted by this secondary method. The concentrations of ash can be very high in close proximity to power plants (PM10 of several hundred micrograms per cubic meter of air) and traces of these aerosols have been found in the ACE-Asia and PACDEX experiments above the Sea of Japan, the Yellow Sea and across the width of the North Pacific.

Low-rank coal oil agglomeration

DOEpatents

Knudson, Curtis L.; Timpe, Ronald C.

1991-01-01

A low-rank coal oil agglomeration process. High mineral content, a high ash content subbituminous coals are effectively agglomerated with a bridging oil which is partially water soluble and capable of entering the pore structure, and usually coal derived.

Characteristics of coking coal burnout

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nakamura, M.; Bailey, J.G.

An attempt was made to clarify the characteristics of coking coal burnout by the morphological analysis of char and fly ash samples. Laboratory-scale combustion testing, simulating an ignition process, was carried out for three kinds of coal (two coking coals and one non-coking coal for reference), and sampled chars were analyzed for size, shape and type by image analysis. The full combustion process was examined in industrial-scale combustion testing for the same kinds of coal. Char sampled at the burner outlet and fly ash at the furnace exit were also analyzed. The difference between the char type, swelling properties, agglomeration,more » anisotropy and carbon burnout were compared at laboratory scale and at industrial scale. As a result, it was found that coking coals produced chars with relatively thicker walls, which mainly impeded char burnout, especially for low volatile coals.« less

Mineralogy and geochemistry of a superhigh-organic-sulfur coal, Yanshan Coalfield, Yunnan, China: Evidence for a volcanic ash component and influence by submarine exhalation

USGS Publications Warehouse

Dai, S.; Ren, D.; Zhou, Y.; Chou, C.-L.; Wang, X.; Zhao, L.; Zhu, Xudong

2008-01-01

The mineralogy and geochemistry of a superhigh-organic-sulfur (SHOS) coal of Late Permian age from the Yanshan Coalfield, Yunnan Province, southwestern China, have been studied using optical microscope, low-temperature ashing plus X-ray diffraction analysis, scanning electron microscope equipped with energy-dispersive X-ray spectrometer, a sequential chemical extraction procedure, and inductively coupled plasma mass spectrometry. The M9 Coal from the Yanshan Coalfield is a SHOS coal that has a total sulfur content of 10.12%-11.30% and an organic sulfur content of 8.77%-10.30%. The minerals in the coal consist mainly of high-temperature quartz, sanidine, albite, muscovite, illite, pyrite, and trace amounts of kaolinite, plagioclase, akermanite, rutile, and dawsonite. As compared with ordinary worldwide (bituminous coals and anthracite) and Chinese coals, the M9 Coal is remarkably enriched in B (268????g/g), F (841????g/g), V (567????g/g), Cr (329????g/g), Ni (73.9????g/g), Mo (204????g/g), and U (153????g/g). In addition, elements including Se (25.2????g/g), Zr (262????g/g), Nb (20.1????g/g), Cd (2.07????g/g), and Tl (2.03????g/g) are also enriched in the coal. Occurrence of high-temperature quartz, sanidine, muscovite, and illite in the M9 Coal is evidence that there is a volcanic ash component in the coal that was derived from acid volcanic ashes fallen into the swamp during peat accumulation. Occurrence of albite and dawsonite in the coal and strong enrichment of some elements, including F, S, V, Cr, Ni, Mo and U, are attributed to the influence by submarine exhalation which invaded along with seawater into the anoxic peat swamp. Abundances of lithophile elements, including rare earth elements, Nb, Y, Zr, and TiO2, indicate that the silicate minerals in the coal were derived from the northern Vietnam Upland to the south of the basin. ?? 2008 Elsevier B.V. All rights reserved.

Soot, organics and ultrafine ash from air- and oxy-fired coal ...

EPA Pesticide Factsheets

This paper is concerned with determining the effects of oxy-combustion of coal on the composition of the ultrafine fly ash. To this end, a 10 W externally heated entrained flow furnace was modified to allow the combustion of pulverized coal in flames under practically relevant stoichiometric ratios (SR = 1.2-1.4), but with the ability to maintain constant residence times (2.3 s). Experiments were conducted using a pulverized bituminous coal under air-combustion and three oxy-combustion inlet oxygen conditions (28, 32, and 36%). Size-classified fly ash samples were collected, and measurements focused on the composition of the total and ultrafine (<0.6 µm) fly ash produced, in particular the soot, elemental carbon (EC), and organic carbon (OC) fractions. Results indicate that although the total fly ash carbon, as measured by loss on ignition, was always acceptably low (<2%) with all three oxy-combustion conditions lower than air-combustion, the ultrafine fly ash for both air-fired and oxy-fired combustion conditions consists primarily of carbonaceous material (50-95%). Subsequent analyses of the carbonaceous component on particles <0.6 µm by a thermal optical method showed that large fractions (52-93%) consisted of OC rather than EC, as expected. This observation was supported by thermogravimetric analysis indicating that for the air, 28% oxy, and 32% oxy conditions, 14-71% of this material may be OC volatilizing between 100 and 550 °C with the remaining

Impact of solid discharges from coal usage in the southwest

PubMed Central

Jones, D. G.; Straughan, I. R.

1978-01-01

The Southwestern region of the United States is extremely wealthy in low sulfur coal resources which must be eventually utilized in response to national energy balance priorities. Fly ash and scrubber sludge can be safely disposed of using properly managed techniques to ensure that any potential impact from elements such as boron, molybdenum, or selenium is rendered insignificant. Alternative methods of solids utilization are presently being developed. Fly ash is presently being marketed commercially as an additive for concrete manufacture. Successful experiments have been completed to demonstrate the manufacture of commercial-grade wallboard from scrubber sludge. Also, greenhouse studies and field experiments have been conducted to demonstrate increased yields of selected crops grown on typical soils amended with fly ash in amounts ranging from 2% to 8%, by weight. These studies also indicate that barium and strontium may be good monitoring indices for determining atmospheric deposition of fly ash, due to their concentration ratios in soil and vegetation samples. Further studies are being conducted to confirm encouraging irrigation and crop-yield data obtained with fly ash amended soils. Finally, the composition of many fly ashes and soils are similar in the Southwest, and there are no anticipated solid discharges from coal usage which cannot be rendered insignificant with proper management of existing and emerging methods of treatment. Compared with the water availability impact of coal usage in the Southwest, the impact of solid waste discharges are insignificant. PMID:738243

Regeneratively cooled coal combustor/gasifier with integral dry ash removal

DOEpatents

Beaufrere, Albert H.

1983-10-04

A coal combustor/gasifier is disclosed which produces a low or medium combustion gas for further combustion in modified oil or gas fired furnaces or boilers. Two concentric shells define a combustion volume within the inner shell and a plenum between them through which combustion air flows to provide regenerative cooling of the inner shell for dry ash operation. A fuel flow and a combustion air flow having opposed swirls are mixed and burned in a mixing-combustion portion of the combustion volume and the ash laden combustion products flow with a residual swirl into an ash separation region. The ash is cooled below the fusion temperature and is moved to the wall by centrifugal force where it is entrained in the cool wall boundary layer. The boundary layer is stabilized against ash re-entrainment as it is moved to an ash removal annulus by a flow of air from the plenum through slots in the inner shell, and by suction on an ash removal skimmer slot.

Evaluation of the mechanical properties of class-F fly ash.

PubMed

Kim, Bumjoo; Prezzi, Monica

2008-01-01

Coal-burning power plants in the United States (US) generate more than 70 million tons of fly ash as a by-product annually. Recycling large volumes of fly ash in geotechnical applications may offer an attractive alternative to the disposal problem as most of it is currently dumped in ponds or landfills. Class-F fly ash, resulting from burning of bituminous or anthracite coals, is the most common type of fly ash in the US. In the present study, the mechanical characteristics (compaction response, compressibility, and shear strength) of class-F fly ash were investigated by performing various laboratory tests (compaction test, one-dimensional compression test, direct shear test and consolidated-drained triaxial compression test) on fly ash samples collected from three power plants in the state of Indiana (US). Test results have shown that despite some morphological differences, class-F fly ash exhibits mechanical properties that are, in general, comparable to those observed in natural sandy soils.

A fine coal circuitry study using column flotation and gravity separation. Quarterly report, 1 March 1995--31 May 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Honaker, R.Q.; Reed, S.

1995-12-31

Column flotation provides excellent recovery of ultrafine coal while producing low ash content concentrates. However, column flotation is not efficient for treating fine coal containing significant amounts of mixed-phase particles. Fortunately, enhanced gravity separation has proved to have the ability to treat the mixed-phased particles more effectively. A disadvantage of gravity separation is that ultrafine clay particles are not easily rejected. Thus, a combination of these two technologies may provide a circuit that maximizes both the ash and sulfur rejection that can be achieved by physical coal cleaning while maintaining a high energy recovery. This project is studying the potentialmore » of using different combinations of gravity separators, i.e., a Floatex hydrosizer and a Falcon Concentrator, and a proven flotation column, which will be selected based on previous studies by the principle investigator. During this reporting period, an extensive separation performance comparison between a pilot-scale Floatex Density Separator (18{times}18-inch) and an existing spiral circuit has been conducted at Kerf-McGee Coal Preparation plan for the treatment of nominally {minus}16 mesh coal. The results indicate that the Floatex is a more efficient separation device (E{sub p}=0.12) than a conventional coal spiral (E{sub p}=0.18) for Illinois seam coals. In addition, the treatment of {minus}100 mesh Illinois No. 5 fine coal from the same plant using Falcon concentrator, column flotation (Packed-Column) and their different combinations was also evaluated. For a single operation, both Falcon concentrator and column flotation can produce a clean coal product with 90% combustible recovery and 5% ash content. In the case of the combined circuit, column flotation followed by the Falcon achieved a higher combustible recovery value (about 75%) than that obtained by the individual units while maintaining an ash content less than 3%.« less

Relationships between waste physicochemical properties, microbial activity and vegetation at coal ash and sludge disposal sites.

PubMed

Woch, Marcin W; Radwańska, Magdalena; Stanek, Małgorzata; Łopata, Barbara; Stefanowicz, Anna M

2018-06-11

The aim of the study was to assess the relationships between vegetation, physicochemical and microbial properties of substrate at coal ash and sludge disposal sites. The study was performed on 32 plots classified into 7 categories: dried ash sedimentation ponds, dominated by a grass Calamagrostis epigejos (AH-Ce), with the admixture of Pinus sylvestris (AH-CePs) or Robinia pseudoacacia (AH-CeRp), dry ash landfill dominated by Betula pendula and Pinus sylvestris (AD-BpPs) or Salix viminalis (AD-Sv) and coal sludge pond with drier parts dominated by Tussilago farfara (CS-Tf) and the wetter ones by Cyperus flavescens (CS-Cf). Ash sites were covered with soil layer imported as a part of technical reclamation. Ash had relatively high concentrations of some alkali and alkaline earth metals, Mn and pH, while coal sludge had high water and C, S, P and K contents. Concentrations of heavy metals were lower than allowable limits in all substrate types. Microbial biomass and, particularly, enzymatic activity in ash and sludge were generally low. The only exception were CS-Tf plots characterized by the highest microbial biomass, presumably due to large deposits of organic matter that became available for aerobic microbial biomass when water level fell. The properties of ash and sludge adversely affected microbial biomass and enzymatic activity as indicated by significant negative correlations between the content of alkali/alkaline earth metals, heavy metals, and macronutrients with enzymatic activity and/or microbial biomass, as well as positive correlations of these parameters with metabolic quotient (qCO 2 ). Plant species richness and cover were relatively high, which may be partly associated with alleviating influence of soil covering the ash. The effect of the admixture of R. pseudoacacia or P. sylvestris to stands dominated by C. epigejos was smaller than expected. The former species increased NNH 4 , NNO 3 and arylsulfatase activity, while the latter reduced activity of the enzyme. Copyright © 2018 Elsevier B.V. All rights reserved.

Influence of metal(loid) bioaccumulation and maternal transfer on embryo-larval development in fish exposed to a major coal ash spill

DOE PAGES

Greeley, Jr., Mark Stephen; Adams, S. Marshall; Elmore, Logan R.; ...

2016-01-03

In December 2008, an earthen retaining wall at the Tennessee Valley Authority (TVA) Kingston Fossil Fuel Plant failed and released 4.1 million m 3 of coal ash to rivers flowing into Watts Bar Reservoir in east Tennessee, United States (U.S.). As part of a comprehensive effort to evaluate the risks to aquatic resources from this spill – the largest in U.S. history – we compared bioaccumulation and maternal transfer of selenium (Se), arsenic (As), and mercury (Hg) in adult redear sunfish ( Lepomis macrolophus), collected two years after the spill from both coal-ash exposed and non-exposed areas of the Emorymore » and Clinch Rivers, with the success of embryo-larval development in their offspring. Whole body and ovary concentrations of Se in female sunfish at three study sites downstream of the spill were significantly elevated (site means = 4.9–5.3 and 6.7–9.0 mg/kg d.w. whole body and ovary concentrations, respectively) compared with concentrations in fish from reference sites upstream of the spill site (2.2–3.2 mg/kg d.w. for whole bodies and 3.6–4.8 mg/kg d.w. for ovaries). However, Se concentrations in coal ash-exposed areas remain below proposed U.S. Environmental Protection Agency (USEPA) criteria for the protection of aquatic life. Site-to-site variation in fish concentrations of As and Hg were not well-correlated with ash-exposure, reflecting the multiple sources of these metal(loid)s in the affected watersheds. In 7-day laboratory tests of embryos and larvae derived from in vitro crosses of eggs and sperm from these field-collected sunfish, fertilization success, hatching success, embryo-larval survival, and incidences of developmental abnormalities did not differ significantly between ash-exposed and non-exposed fish. Furthermore, these developmental endpoints were not correlated with whole body or ovary concentrations of Se, As, or Hg in the maternal fish, or with fish size, ovary weight, or gonadal-somatic indices. Furthermore, results from this and related studies associated with the Kingston coal ash spill are consistent with proposed USEPA fish-based water quality criteria for Se, and to date continue to suggest that long-term exposures to sediment containing residual ash may not present a significant chronic risk to fish populations exposed to this major coal ash release.« less

Influence of metal(loid) bioaccumulation and maternal transfer on embryo-larval development in fish exposed to a major coal ash spill

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greeley, Jr., Mark Stephen; Adams, S. Marshall; Elmore, Logan R.

In December 2008, an earthen retaining wall at the Tennessee Valley Authority (TVA) Kingston Fossil Fuel Plant failed and released 4.1 million m 3 of coal ash to rivers flowing into Watts Bar Reservoir in east Tennessee, United States (U.S.). As part of a comprehensive effort to evaluate the risks to aquatic resources from this spill – the largest in U.S. history – we compared bioaccumulation and maternal transfer of selenium (Se), arsenic (As), and mercury (Hg) in adult redear sunfish ( Lepomis macrolophus), collected two years after the spill from both coal-ash exposed and non-exposed areas of the Emorymore » and Clinch Rivers, with the success of embryo-larval development in their offspring. Whole body and ovary concentrations of Se in female sunfish at three study sites downstream of the spill were significantly elevated (site means = 4.9–5.3 and 6.7–9.0 mg/kg d.w. whole body and ovary concentrations, respectively) compared with concentrations in fish from reference sites upstream of the spill site (2.2–3.2 mg/kg d.w. for whole bodies and 3.6–4.8 mg/kg d.w. for ovaries). However, Se concentrations in coal ash-exposed areas remain below proposed U.S. Environmental Protection Agency (USEPA) criteria for the protection of aquatic life. Site-to-site variation in fish concentrations of As and Hg were not well-correlated with ash-exposure, reflecting the multiple sources of these metal(loid)s in the affected watersheds. In 7-day laboratory tests of embryos and larvae derived from in vitro crosses of eggs and sperm from these field-collected sunfish, fertilization success, hatching success, embryo-larval survival, and incidences of developmental abnormalities did not differ significantly between ash-exposed and non-exposed fish. Furthermore, these developmental endpoints were not correlated with whole body or ovary concentrations of Se, As, or Hg in the maternal fish, or with fish size, ovary weight, or gonadal-somatic indices. Furthermore, results from this and related studies associated with the Kingston coal ash spill are consistent with proposed USEPA fish-based water quality criteria for Se, and to date continue to suggest that long-term exposures to sediment containing residual ash may not present a significant chronic risk to fish populations exposed to this major coal ash release.« less

Low-rank coal oil agglomeration

DOEpatents

Knudson, C.L.; Timpe, R.C.

1991-07-16

A low-rank coal oil agglomeration process is described. High mineral content, a high ash content subbituminous coals are effectively agglomerated with a bridging oil which is partially water soluble and capable of entering the pore structure, and is usually coal-derived.

Effect of combustion temperature on the emission of trace elements under O2/CO2 atmosphere during coal combustion

NASA Astrophysics Data System (ADS)

Qu, Chengrui; Zhang, Mo; Mann, Michael. D.

2018-03-01

The effect of combustion temperature on the emission of trace elementswas studied under O2/CO2 atmosphere during coal combustion in a laboratory scale fluidized bed combustor. The elemental composition of fine fly ash particles collected with a low pressure impactor(LPI)was quantified by X-Ray F1uorescence Spectrometer (XRF). The elemental composition of coal and bottom ash was quantified byinductively coupled plasma-atomic emission spectroscopy (ICP-AES). The results indicate that the contents of Mn, Zn, Cd and Cr in the fly ash increase with the rise of combustion temperature. It is found that the enrichment of Zn and Cd is greater in the submicrometer particles than the supermicrometer particles, but Mn and Cr do not enrich in the submicrometer particles. Mn, Zn, Cd and Cr display one peak around 0.1 μm. The relative enrichment factor (Rij) of four elements is in the order of Zn, Cd, Mn and Cr. Zn and Cd are mostly retained in fly ashwhileMn and Cr are retained in both the fly ash and bottom ash.

Development of Self-Powered Wireless-Ready High Temperature Electrochemical Sensors for In-Situ Corrosion Monitoring for Boiler Tubes in Next Generation Coal-based Power Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Xingbo

The key innovation of this project is the synergy of the high temperature sensor technology based on the science of electrochemical measurement and state-of-the-art wireless communication technology. A novel self-powered wireless high temperature electrochemical sensor system has been developed for coal-fired boilers used for power generation. An initial prototype of the in-situ sensor demonstrated the capability of the wireless communication system in the laboratory and in a pilot plant (Industrial USC Boiler Setting) environment to acquire electrochemical potential and current signals during the corrosion process. Uniform and localized under-coal ash deposit corrosion behavior of Inconel 740 superalloy has been studiedmore » at different simulated coal ash hot corrosion environments using the developed sensor. Two typical potential noise patterns were found to correlate with the oxidation and sulfidation stages in the hot coal ash corrosion process. Two characteristic current noise patterns indicate the extent of the corrosion. There was a good correlation between the responses of electrochemical test data and the results from corroded surface analysis. Wireless electrochemical potential and current noise signals from a simulated coal ash hot corrosion process were concurrently transmitted and recorded. The results from the performance evaluation of the sensor confirm a high accuracy in the thermodynamic and kinetic response represented by the electrochemical noise and impedance test data.« less

Quality of economically extractable coal beds in the Gillette coal field as compared with other Tertiary coal beds in the Powder River basin, Wyoming and Montana

USGS Publications Warehouse

Ellis, Margaret S.

2002-01-01

The Powder River Basin, and specifically the Gillette coal field, contains large quantities of economically extractable coal resources. These coal resources have low total sulfur content and ash yield, and most of the resources are subbituminous in rank. A recent U.S Geological Survey study of economically extractable coal in the Gillette coal field focused on five coal beds, the Wyodak rider, Upper Wyodak, Canyon, Lower Wyodak-Werner, and Gates/Kennedy. This report compares the coal quality of these economically extractable coal beds to coal in the Wyodak-Anderson coal zone in the Powder River Basin and in the Gillette coal field (Flores and others, 1999) and other produced coal in the Gillette coal field (Glass, 2000). The Upper Wyodak, Canyon, and Lower Wyodak/Werner beds are within the Wyodak-Anderson coal zone. Compared with all coal in the Wyodak-Anderson coal zone, both throughout the Powder River Basin and just within the Gillette coal field; the thick, persistent Upper Wyodak coal bed in the Gillette coal field has higher mean gross calorific value (8,569 Btu/lb), lower mean ash yield (5.8 percent), and lower mean total sulfur content (0.46 percent).

Effect of textile industrial effluent on tree plantation and soil chemistry.

PubMed

Singh, G; Bala, N; Rathod, T R; Singh, B

2001-01-01

A field study was conducted at Arid Forest Research Institute to study the effect of textile industrial effluent on the growth of forest trees and associated soil properties. The effluent has high pH, electrical conductivity (EC), sodium adsorption ratio (SAR) and residual sodium carbonate (RSC) whereas the bivalent cations were in traces. Eight months old seedlings of Acacia nilotica, Acacia tortilis, Albizia lebbeck, Azadirachta indica, Parkinsonia aculeata and Prosopis juliflora were planted in July 1993. Various treatment regimes followed were; irrigation with effluent only (W1), effluent mixed with canal water in 1:1 ratio (W2), irrigation with gypsum treated effluent (W3), gypsum treated soil irrigated with effluent (W4) and wood ash treated soil irrigated with effluent (W5). Treatment regime W5 was found the best where plants attained (mean of six species) 173 cm height, 138 cm crown diameter and 9.2 cm collar girth at the age of 28 months. The poorest growth was observed under treatment regime of W3. The growth of the species varied significantly and the maximum growth was recorded for P. juliflora (188 cm height, 198 cm crown diameter and 10.0 cm collar girth). The minimum growth was recorded for A. lebbeck. Irrigation with effluent resulted in increase in percent organic matter as well as in EC. In most of the cases there were no changes in soil pH except in W5 where it was due to the effect of wood ash. Addition of wood ash influenced plant growth. These results suggest that tree species studied (except A. lebbeck) can be established successfully using textile industrial wastewater in arid region.

Analysis of natural radioactivity in Yatağan coal - fired power plant in Turkey

NASA Astrophysics Data System (ADS)

Altıkulaç, Aydan; Turhan, Şeref; Gümüş, Hasan

2017-09-01

Use of the coal in order to generate electricity increases the exposure of people to radiation. In this paper, the activity concentrations of nuclides 226Ra, 232Th and 40K in samples of coal and bottom ash from the Yatagan Coal-Fired thermal power plant determined using gamma ray spectrometer with a NaI(Tl) scintillation detector. The mean activity concentrations of 226Ra, 232Th, and 40K in the coal were found to be 37.2±2.8 Bqkg-1, 51.8±3.4 Bqkg-1 and 166.7±11.1 Bqkg-1, respectively. Whereas in the bottom ashes, the concentrations of the corresponding radionuclides were found to be 62.2±5.6 Bqkg-1, 87.4±5.9 Bqkg-1 and 221.0 ±12.5 Bqkg-1, respectively. The findings show that bottom ashes show higher activity concentrations of related radionuclide to coal samples. The absorbed gamma dose rate in outdoor air DROUT and annual effective dose rate (AED) from coal were calculated to define radıologıcal rısk. The average findings of annual effective doses were detected as 68.6±5.1 μSvy-1 and 110.3±11.2 μSvy-1, respectively.

Understanding selected trace elements behavior in a coal-fired power plant in Malaysia for assessment of abatement technologies.

PubMed

Mokhtar, Mutahharah M; Taib, Rozainee M; Hassim, Mimi H

2014-08-01

The Proposed New Environmental Quality (Clean Air) Regulation 201X (Draft), which replaces the Malaysia Environmental Quality (Clean Air) 1978, specifies limits to additional pollutants from power generation using fossil fuel. The new pollutants include Hg, HCl, and HF with limits of 0.03, 100, and 15 mg/N-m3 at 6% O2, respectively. These pollutants are normally present in very small concentrations (known as trace elements [TEs]), and hence are often neglected in environmental air quality monitoring in Malaysia. Following the enactment of the new regulation, it is now imperative to understand the TEs behavior and to assess the capability of the existing abatement technologies to comply with the new emission limits. This paper presents the comparison of TEs behavior of the most volatile (Hg, Cl, F) and less volatile (As, Be, Cd, Cr, Ni, Se, Pb) elements in subbituminous and bituminous coal and coal combustion products (CCP) (i.e., fly ash and bottom ash) from separate firing of subbituminous and bituminous coal in a coal-fired power plant in Malaysia. The effect of air pollution control devices configuration in removal of TEs was also investigated to evaluate the effectiveness of abatement technologies used in the plant. This study showed that subbituminous and bituminous coals and their CCPs have different TEs behavior. It is speculated that ash content could be a factor for such diverse behavior In addition, the type of coal and the concentrations of TEs in feed coal were to some extent influenced by the emission of TEs in flue gas. The electrostatic precipitator (ESP) and seawater flue gas desulfurization (FGD) used in the studied coal-fired power plant were found effective in removing TEs in particulate and vapor form, respectively, as well as complying with the new specified emission limits. Implications: Coals used by power plants in Peninsular Malaysia come from the same supplier (Tenaga Nasional Berhad Fuel Services), which is a subsidiary of the Malaysia electricity provider (Tenaga Nasional Berhad). Therefore, this study on trace elements behavior in a coal-fired power plant in Malaysia could represent emission from other plants in Peninsular Malaysia. By adhering to the current coal specifications and installation of electrostatic precipitator (ESP) and flue gas desulfurization, the plants could comply with the limits specified in the Malaysian Department of Environment (DOE) Scheduled Waste Guideline for bottom ash and fly ash and the Proposed New Environmental Quality (Clean Air) Regulation 201X (Draft).

Inorganic geochemistry of domed peat in Indonesia and its implication for the origin of mineral matter in coal

USGS Publications Warehouse

Neuzil, Sandra G.; Supardi,; Cecil, C. Blaine; Kane, Jean S.; Soedjono, Kadar

1993-01-01

The inorganic geochemistry of three domed ombrogenous peat deposits in Riau and West Kalimantan provinces, Indonesia, was investigated as a possible modern analogue for certain types of low-ash, low-sulfur coal. Mineral matter entering the deposits is apparently limited to small amounts from the allogenic sources of dryfall, rainfall, and diffusion from substrate pore water. In the low-ash peat in the interior of the deposits, a large portion of the mineral matter is authigenic and has been mobilized and stabilized by hydrological, chemical, and biological processes and conditions.Ash yield and sulfur content are low through most of the peat deposits and average 1.1% and 0.14%, respectively, on a moisture-free basis. Ash and sulfur contents only exceed 5% and 0.3%, respectively, near the base of the deposits, with maximum concentrations of 19.9% ash and 0.56% sulfur. Peat water in all three deposits has a low pH, about 4 units, and low dissolved cation concentration, averaging 14 ppm. Near the base, in the geographic interior of each peat deposit, pH is about two units higher and dissolved cation concentration averages 110 ppm. Relative concentrations of the inorganic constituents vary, resulting in chemical facies in the peat. In general, Si, Al, and Fe are the abundant inorganic constituents, although Mg, Ca, and Na dominate in the middle horizon in the geographic interior of coastal peat deposits.The composition of the three deposits reported in this paper indicates that domed ombrogenous peat deposits will result in low ash and sulfur coal, probably less than 10% ash and 1% sulfur, even if marine rocks are laterally and vertically adjacent to the coal.

MSW fly ash stabilized with coal ash for geotechnical application.

PubMed

Kamon, M; Katsumi, T; Sano, Y

2000-09-15

The solidification and stabilization of municipal solid waste (MSW) fly ash for the purpose of minimizing the geo-environmental impact caused by toxic heavy metals as well as ensuring engineering safety (strength and soaking durability) are experimentally evaluated. The mixtures of MSW fly ash stabilized with cement and fluidized bed combustion coal fly ash (FCA) were used for unconfined compressive strength tests, leachate tests, and soaking tests. The behavior of soluble salts contained in the MSW fly ash significantly affects strength development, soaking durability, and the hardening reaction of the stabilized MSW fly ash mixtures. The cement stabilization of the MSW fly ash does not have enough effect on strength development and soaking durability. The addition of cement only contributes to the containment of heavy metals due to the high level of alkalinity. When using FCA as a stabilizing agent for MSW fly ash, the mixture exhibits high strength and durability. However, the Cd leachate cannot be prevented in the early stages of curing. Using a combination of cement and FCA as a MSW fly ash stabilizer can attain high strength, high soaking durability, and the containment of heavy metals. The stabilized MSW fly ash with cement and FCA can be practically applied to embankments.

pH-dependent leaching of dump coal ash - retrospective environmental analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Popovic, A.; Djordjevic, D.

2009-07-01

Trace and major elements in coal ash particles from dump of 'Nikola Tesla A' power plant in Obrenovac near Belgrade (Serbia) can cause pollution, due to leaching by atmospheric and surface waters. In order to assess this leaching potential, dump ash samples were subjected to extraction with solutions of decreasing pH values (8.50, 7.00, 5.50, and 4.00), imitating the reactions of the alkaline ash particles with the possible alkaline, neutral, and acidic (e.g., acid rain) waters. The most recently deposited ash represents the greatest environmental threat, while 'aged' ash, because of permanent leaching on the dump, was shown to havemore » already lost this pollution potential. On the basis of the determined leachability, it was possible to perform an estimation of the acidity of the regional rainfalls in the last decades.« less

Damage cost of the Dan River coal ash spill

Treesearch

A. Dennis Lemly

2015-01-01

The recent coal ash spill on the Dan River in North Carolina, USA has caused several negative effects on the environment and the public. In this analysis, I report a monetized value for these effects after the first 6 months following the spill. The combined cost of ecological damage, recreational impacts, effects on human health and consumptive use, and esthetic value...

Comparison of H2S adsorption by two hydrogel composite (HBC) derived by Empty Fruit Bunch (EFB) biochar and Coal Fly Ash (CFA)

NASA Astrophysics Data System (ADS)

Meri, N. H.; Alias, A. B.; Talib, N.; Rashid, Z. A.; Ghani, W. A. W. A. K.

2018-03-01

This study are covered the adsorption performance of two adsorbent Empty Fruit Bunch Hydrogel Biochar Composite (EFB-HBC) and Coal Fly Ash Hydrogel Composite (CFA-HC) on hydrogen sulphide. The EFB biochar were produce by pyrolysed and heated from room temperature to 550˚C at 10˚C/min under the Nitrogen flow. Meanwhile, coal fly ash collected from a power plant located in Selangor, Malaysia. Both of the materials is a waste from different industries and became the precursor to our adsorbents. EFB biochar and coal fly ash has been synthesized to become hydrogel by polymerization process with acrylamide (AAm) as monomer, N,N’-methylene bisacry lamide (MBA) as cross linker and ammonium persulfate (APS) as initiator. In addition, because of the speciality of hydrogel itself, which is has high ability in storing water, the effect of H2O wetness on EFB-HBC and CFA-HC were investigate in adsorption of H2S. EFB-HBC gave a longest breakthrough time and highest adsorption capacity compared with CFA-HC in both condition (dry/wet). The result also indicated that, the increased the bed height, increased the adsorption capacity.

Interaction of planar and nonplanar organic contaminants with coal fly ash: effects of polar and nonpolar solvent solutions.

PubMed

Burgess, Robert M; Ryba, Stephan A; Cantwell, Mark G; Gundersen, Jennifer L; Tien, Rex; Perron, Monique M

2006-08-01

Coal fly ash has a very high sorption capacity for a variety of anthropogenic contaminants and has been used to cleanse wastewater of pollutants for approximately 40 years. Like other black carbons, the planar structure of the residual carbon in fly ash results in elevated affinities for planar organic contaminants, such as polycyclic aromatic hydrocarbons (PAHs) and some polychlorinated biphenyls (PCBs). The present study was performed to understand better the mechanisms affecting the strong interaction between planar contaminants and coal fly ash. The removal of 10 PCBs and 10 PAHs by several fly ashes and other sorbents was evaluated under different experimental conditions to highlight the intermolecular forces influencing adsorption. Varying fly ash concentration and solvent system composition indicated that dispersive interactions were most prevalent. For the PCBs, empirical results also were compared to molecular modeling estimates of the energy necessary for the PCB molecule to assume a planar conformation (PCe). The PCe levels ranged from 8 to 25 kcal/mol, depending on the degree of ortho-substituted chlorination of the PCB. A significant correlation between PCe and PCB removal from solution was observed for the fly ashes and activated carbon, whereas the nonplanar sorbent octadecyl (C18) indicated no relationship. These findings demonstrate the strong interaction between black carbon fly ash and planar organic contaminants. Furthermore, as exemplified by the PCBs, these results show how this interaction is a function of a contaminant's ability to assume a planar conformation.

Effects of calcium in ash on the corrosion performance of Ni-based alloys in simulated oxy-fuel environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zeng, Z.; Natesan, K.; Cai, Z.

Increasing the efficiency of coal power plants requires raising the operating temperature above 650°C. However, coal ash can severely attack alloy materials at high temperature. For example, the corrosion rates of commercial Fe- and Ni-based alloys are generally greater than 2 mm/year at 750°C in the gas environment of oxy-fuel combustion. Thus, a critical study is needed to determine the effect of the constituents in the ash on corrosion and find an approach to reduce the corrosion rates in an ash-laden environment at high temperature. The role of CaO in the ash (typical of U.S. Western coal ash) has beenmore » investigated in laboratory exposure environments with various structural alloys. Detailed results are presented on weight change, scale thickness, internal penetration, microstructural characteristics of corrosion products, and the cracking of scales for the alloys after exposure at 750°C. The thermal stability of K3Al(SO4)3 under the environment of oxy-fuel combustion was determined by thermogravimetric analysis and differential thermal analysis. The reaction of this low melting temperature salt with the CaO-containing ash is discussed. In addition, we performed synchrotron nanobeam X-ray analysis to study the phase and chemical composition of the oxide layers on the alloy surface. Results from these studies are used to address the role of CaO in ash in the long-term corrosion performance of alloys.« less

The comparative analysis of heat transfer efficiency in the conditions of formation of ash deposits in the boiler furnaces, with taking into account the crystallization of slag during combustion of coal and water-coal fuel

NASA Astrophysics Data System (ADS)

Salomatov, V. V.; Kuznetsov, G. V.; Syrodoy, S. V.

2017-11-01

The results of the numerical simulation of heat transfer from the combustion products of coal and coal-water fuels (CWF) to the internal environment. The mathematical simulation has been carried out on the sample of the pipe surfaces of the combustion chamber of the boiler unit. The change in the characteristics of heat transfer (change of thermochemical characteristics) in the conditions of formation of the ash deposits have been taken into account. According to the results of the numerical simulation, the comparative analysis of the efficiency of heat transfer has been carried out from the furnace environment to the inside pipe coolant (water, air, or water vapor) from the combustion of coal and coal-water fuels. It has been established that, in the initial period of the boiler unit operation during coal fuel combustion the efficiency of heat transfer from the combustion products of the internal environment is higher than when using CWF. The efficiency of heat transfer in CWF combustion conditions is more at large times (τ≥1.5 hours) of the boiler unit. A significant decrease in heat flux from the combustion products to the inside pipe coolant in the case of coal combustion compared to CWF has been found. It has been proved that this is due primarily to the fact that massive and strong ash deposits are formed during coal combustion.

Constitution of Drop-Tube-Generated Coal Chars from Vitrinite- and Inertinite-Rich South African Coals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Louw, Enette B.; Mitchell, Gareth D.; Wang, Juan

The structural transformations of coal and the resultant char morphologies are strongly dependent on the initial structure and degree of thermoplasticity achieved during coal-to-char transition. These are a function of petrographic composition, rank, particle size, and heating rate and strongly affect combustion behavior. This study compares the devolatilization and subsequent combustion behavior of an inertinite-rich (87.7% dmmf) and a vitrinite-rich (91.8% dmmf) South African coal, wet-screened to a narrow particle size distribution of 200 x 400 mesh. Pyrolysis chars were generated under rapid-heating conditions (104-105 °C/s) in a drop-tube reactor to closely resemble chars generated in pulverized combustion conditions. Themore » inertinite-rich coal took ~ 400 ms to devolatilize in the drop-tube, compared to only ~ 240 ms for the vitrinite-rich sample. The chemical and physical structure (the constitution) of the chars were investigated through a range of chemical, physical, and optical characteristics including the maceral differences, and high ash yields. To evaluate the combustion reactivity non-isothermal burn-out profiles were obtained through thermogravimetrical analyses (TGA) in air. The vitrinite-rich char had on average 20% higher reaction rates than the inertinite-rich char under the various combustion conditions. The char samples were de-ashed with HCl and HF acid which resulted in an increase in combustion reactivity. The maximum reaction rate of the high-ash (36% ash yield) inertinite-rich char increased with 80% after de-ashing. While the vitrinite-rich char with an ash yield of 15%, had a 20% increase in reactivity after de-ashing. The ash acted as a barrier, and the removal of ash most likely increased the access to reactive surface area. The chemical and physical structures of the chars were characterized through a range of different analytical techniques to quantify the factors contributing to reactivity differences. The morphologies of the chars were characterized with SEM and optical microscopy, while quantitative information on the ordered nature of chars was obtained through XRD on de-ashed chars. The inertinite-rich coal experienced limited fluidity during heat-treatment, resulting in slower devolatilization, limited growth in crystallite height (11.8 to 12.6Å), only rounding of particle edges, and producing > 40% of mixed-dense type chars. The vitrinite-char showed more significant structural transformations; producing mostly (80%) extensively swollen crassisphere, tenuisphere, and network-type chars, and XRD showed a large increase in crystallite height (4.3 to 11.7Å). Nitrogen adsorption and small-angle X-ray scattering (SAXS) were utilized to compare the nitrogen surface areas and pore size distributions. Both chars were mostly mesoporous but the inertinite-rich char had double the average pore size, which also resulted in a larger nitrogen surface area since nitrogen can only access surface areas in larger pores. The BET surface area was 3.9 and 2.7 m2/g for the inertinite- and vitrinite-rich chars respectively. SAXS data showed that the vitrinite-rich char had 60% higher frequencies of pores in the micropore range. Helium porosimetry indicated that the inertinite-rich coal and resultant char had higher densities than the vitrinite coal and char; 1.6 and 2.0 g/cm3, compared to 1.3 and 1.9 g/cm3 (dry basis). Non-isothermal TGA burnout profiles showed the inertinite-rich char had a burnout temperature of 680°C, slightly higher than the vitrinite-rich char’s 650 °C. This, along with the peak shape and position in the burnout profiles indicate that the vitrinite-rich char has a higher reactivity. The higher reactivity is due to a combination of factors likely including less organization, grater porosity and access to the reactive site, less ash blocking, and char morphology differences.« less

Hierarchical zeolites from class F coal fly ash

NASA Astrophysics Data System (ADS)

Chitta, Pallavi

Fly ash, a coal combustion byproduct is classified as types class C and class F. Class C fly ash is traditionally recycled for concrete applications and Class F fly ash often disposed in landfills. Class F poses an environmental hazard due to disposal and leaching of heavy metals into ground water and is important to be recycled in order to mitigate the environmental challenges. A major recycling option is to reuse the fly ash as a low-cost raw material for the production of crystalline zeolites, which serve as catalysts, detergents and adsorbents in the chemical industry. Most of the prior literature of fly ash conversion to zeolites does not focus on creating high zeolite surface area zeolites specifically with hierarchical pore structure, which are very important properties in developing a heterogeneous catalyst for catalysis applications. This research work aids in the development of an economical process for the synthesis of high surface area hierarchical zeolites from class F coal fly ash. In this work, synthesis of zeolites from fly ash using classic hydrothermal treatment approach and fusion pretreatment approach were examined. The fusion pretreatment method led to higher extent of dissolution of silica from quartz and mullite phases, which in turn led to higher surface area and pore size of the zeolite. A qualitative kinetic model developed here attributes the difference in silica content to Si/Al ratio of the beginning fraction of fly ash. At near ambient crystallization temperatures and longer crystallization times, the zeolite formed is a hierarchical faujasite with high surface area of at least 360 m2/g. This work enables the large scale recycling of class F coal fly ash to produce zeolites and mitigate environmental concerns. Design of experiments was used to predict surface area and pore sizes of zeolites - thus obviating the need for intense experimentation. The hierarchical zeolite catalyst supports tested for CO2 conversion, yielded hydrocarbons up to C9, a performance attesting the hierarchal pore structure. The preliminary techno-economic feasibility assessment demonstrates a net energy saving of 75% and cost saving of 63% compared to the commercial zeolite manufacturing process.

Selenium content and oxidation states in fly ashes from western U.S. coals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mattigod, Shas V; Quinn, Thomas R

2003-08-01

A selective extraction scheme was developed for the determination of the oxidation states of Se species in coal ashes. As compared to HF dissolution, extractions with 70% HC1O4 mobilized 90 to 100% of all compound and redox forms of Se from four of the five fly ashes. Extractions with 16M HNO3 did not mobilize all forms of Se as effectively as perchloric acid. Both oxidized forms of Se (IV and VI) were completely mobilized by 12M HCl extraction. Deionized-distilled water was not an effective extractant for mobilizing all compound forms of Se(IV) from fly ashes. Extraction data (70% HClO4, 16Mmore » HNO3, 12M HCl, DI water) indicated that the solid:solution ratio is a critical factor in Se extractability from fly ashes. Maximum extractions in all cases were obtained only with very high (1:500) solid:solution ratios. Extraction times from 1.5 to 25 hours did not significantly change Se extractability with any of the extractants except with 12M HCl, which required a minimum reaction time of 48 hours to attain maximum Se extractability. Reaction times shorter than the critical time and low solid:solution ratios significantly affected Se extractability from these fly ashes. Measurements of Se content and redox state in particle size and density fractions five western United States coal ashes indicated that typically, the Se content increased with decreasing particle size.. However, no consistent trend in Se concentration between the light and heavy density fractions of <2.7-m size fraction was observed. Selenium redox state data indicated that only Se(0) and Se(IV) forms were present in these five coal ashes. The presence of Se(IV) is significant since it is much more easily mobilized than the elemental form. Examination of fly ashes by the proposed scheme to determine Se redox species could permit better estimation of the Se content of plants grown on fly ash amended soils.« less

Coal combustion products

USGS Publications Warehouse

Kalyoncu, R.S.; Olson, D.W.

2001-01-01

Coal-burning powerplants, which supply more than half of U.S. electricity, also generate coal combustion products, which can be both a resource and a disposal problem. The U.S. Geological Survey collaborates with the American Coal Ash Association in preparing its annual report on coal combustion products. This Fact Sheet answers questions about present and potential uses of coal combustion products.

Evaluation of an enhanced gravity-based fine-coal circuit for high-sulfur coal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mohanty, M.K.; Samal, A.R.; Palit, A.

One of the main objectives of this study was to evaluate a fine-coal cleaning circuit using an enhanced gravity separator specifically for a high sulfur coal application. The evaluation not only included testing of individual unit operations used for fine-coal classification, cleaning and dewatering, but also included testing of the complete circuit simultaneously. At a scale of nearly 2 t/h, two alternative circuits were evaluated to clean a minus 0.6-mm coal stream utilizing a 150-mm-diameter classifying cyclone, a linear screen having a projected surface area of 0.5 m{sup 2}, an enhanced gravity separator having a bowl diameter of 250 mmmore » and a screen-bowl centrifuge having a bowl diameter of 500 mm. The cleaning and dewatering components of both circuits were the same; however, one circuit used a classifying cyclone whereas the other used a linear screen as the classification device. An industrial size coal spiral was used to clean the 2- x 0.6-mm coal size fraction for each circuit to estimate the performance of a complete fine-coal circuit cleaning a minus 2-mm particle size coal stream. The 'linear screen + enhanced gravity separator + screen-bowl circuit' provided superior sulfur and ash-cleaning performance to the alternative circuit that used a classifying cyclone in place of the linear screen. Based on these test data, it was estimated that the use of the recommended circuit to treat 50 t/h of minus 2-mm size coal having feed ash and sulfur contents of 33.9% and 3.28%, respectively, may produce nearly 28.3 t/h of clean coal with product ash and sulfur contents of 9.15% and 1.61 %, respectively.« less

Temporal and spatial variations in fly ash quality

USGS Publications Warehouse

Hower, J.C.; Trimble, A.S.; Eble, C.F.

2001-01-01

Fly ash quality, both as the amount of petrographically distinguishable carbons and in chemistry, varies in both time and space. Temporal variations are a function of a number of variables. Variables can include variations in the coal blend organic petrography, mineralogy, and chemistry; variations in the pulverization of the coal, both as a function of the coal's Hardgrove grindability index and as a function of the maintenance and settings of the pulverizers; and variations in the operating conditions of the boiler, including changes in the pollution control system. Spatial variation, as an instantaneous measure of fly ash characteristics, should not involve changes in the first two sets of variables listed above. Spatial variations are a function of the gas flow within the boiler and ducts, certain flow conditions leading to a tendency for segregation of the less-dense carbons in one portion of the gas stream. Caution must be applied in sampling fly ash. Samples from a single bin, or series of bins, m ay not be representative of the whole fly ash, providing a biased view of the nature of the material. Further, it is generally not possible to be certain about variation until the analysis of the ash is complete. ?? 2001 Elsevier Science B.V. All rights reserved.

Selenium bioaccumulation in fish exposed to coal ash at the Tennessee Valley Authority Kingston spill site.

PubMed

Mathews, Teresa J; Fortner, Allison M; Jett, R Trent; Morris, Jesse; Gable, Jennifer; Peterson, Mark J; Carriker, Neil

2014-10-01

In December 2008, 4.1 million cubic meters of coal ash were released into the Emory and Clinch Rivers by the Tennessee Valley Authority Kingston Fossil Plant. Coal ash contains several contaminants, including the bioaccumulative metalloid selenium (Se). Because Se is predominantly accumulated in aquatic organisms through dietary rather than aqueous exposure, tissue-based toxicity thresholds for Se are currently being considered. The proposed threshold concentrations range between 4 μg/g and 9 μg/g Se (dry wt.) in whole body fish, with a proposed fillet threshold of 11.8 μg/g. In the present study, the authors examined the spatial and temporal trends in Se bioaccumulation and examined the relationship between the Se content in fillets and in whole bodies of fish collected around the Kingston spill site to determine whether Se bioaccumulation was a significant concern at the ash spill site. Whereas Se concentrations in fish (whole bodies and fillets) were elevated at sampling locations affected by the Kingston ash spill relative to reference locations, concentrations do not appear to be above risk thresholds and have not been increasing over the 5-yr period since the spill. These findings are not only relevant to guiding the human health and ecological risk assessments at the Kingston ash spill site, but because of current national discussions on appropriate guidelines for Se in fish as well for the disposal of coal combustion wastes, the results are also relevant to the general understanding of Se bioaccumulation in contaminated water bodies. © 2014 SETAC.

Relationship between selenium body burdens and tissue concentrations in fish exposed to coal ash at the Tennessee Valley Authority Kingston spill site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mathews, Teresa J; Fortner, Allison M; Jett, Robert T

2014-01-01

In December 2008, 4.1 million m3 of coal ash were released into the Emory and Clinch Rivers by the Tennessee Valley Authority (TVA) Kingston Fossil Plant. Coal ash contains several contaminants, including the bioaccumulative metalloid selenium (Se). Because Se is predominantly accumulated in aquatic organisms through dietary, rather than aqueous exposure, tissue-based toxicity thresholds for Se are currently being considered. The proposed threshold concentrations range between 4-9 g/g Se (dry wt.) in whole body fish, with a proposed fillet threshold of 11.8 g/g. In the present study we examined the spatial and temporal trends in Se bioaccumulation and examined themore » relationship between the Se content in fillets and in whole bodies of fish collected around the Kingston spill site to determine whether Se bioaccumulation was a significant concern at the ash spill site. While Se concentrations in fish (whole bodies and fillets) were elevated at sampling locations affected by the Kingston ash spill relative to reference locations, concentrations do not appear to be above risk thresholds and have not been increasing over the five year period since the spill. Our results are not only relevant to guiding the human health and ecological risk assessments at the Kingston ash spill site, but because of current national discussions on appropriate guidelines for Se in fish as well for the disposal of coal combustion wastes, our results are also relevant to the general understanding of Se bioaccumulation in contaminated water bodies.« less

40 CFR 420.13 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2014 CFR

2014-07-01

... exceed 13.3 per cent of the above limitations, shall be provided for process wastewaters from coke oven... (except those from coal charging and coke pushing emission controls), coal tar processing operations and coke plant groundwater remediation systems, but only to the extent such systems generate process...

40 CFR 420.13 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2013 CFR

2013-07-01

... exceed 13.3 per cent of the above limitations, shall be provided for process wastewaters from coke oven... (except those from coal charging and coke pushing emission controls), coal tar processing operations and coke plant groundwater remediation systems, but only to the extent such systems generate process...

Concentration and distribution of sixty-one elements in coals from DPR Korea

USGS Publications Warehouse

Hu, Jiawen; Zheng, B.; Finkelman, R.B.; Wang, B.; Wang, M.; Li, S.; Wu, D.

2006-01-01

Fifty coal samples (28 anthracite and 22 lignites) were collected from both main and small coal mines in DPR Korea prioritized by resource distribution and coal production. The concentrations of 61 elements in 50 coal samples were determined by several multielement and element-specific techniques, including inductively coupled plasma atomic emission spectrometry (ICP-AES), and inductively coupled plasma mass spectrometry (ICP-MS), ion chromatogram (IC), cold-vapor atomic absorption spectrometry (CV-AAS), and hydride generation atomic absorption spectrometry (HGAAS). The ranges, arithmetic means and geometric means of concentrations of these elements are presented. A comparison with crustal abundances (Clarke values) shows that some potentially hazardous elements in the coals of DPR Korea are highly enriched Li, B, S, Cl, Zn, As, Se, Cd, Sn, Sb, W, Te, Hg, Ag, Pb, and La, Ce, Dy, Tm, Ge, Mo, Cs, Tl, Bi, Th and U are moderately enriched. A comparison of ranges and means of elemental concentrations in DPR Korea, Chinese, and world coals shows the ranges of most elements in DPR Korea coals are very close to the ranges of world coals. Arithmetic means of most elements in DPR Korea coals are close to that of American coals. Most elements arithmetic means are higher in Jurassic and Paleogene coals than coals of other ages. In DPR Korea coals, only seven elements in early Permian coals are higher than other periods: Li, Zn, Se, Cd, Hg, Pb, and Bi. Only five elements B, As, Sr, Mo, W in Neogene coals have arithmetic means higher than others. SiO2 and Al2O 3 in ashes are more than 70% except six samples. The correlation between ash yields and major elements from high to low is in the order of Si>Al>Ti>K>Mg>Fe>Na>Ca>P>S. Most elements have high positive correlation with ash (r>0.5) and show high inorganic affinity. ?? 2005 Elsevier Ltd. All rights reserved.

Improved coal-slurry pipeline

NASA Technical Reports Server (NTRS)

Dowler, W. L.

1979-01-01

High strength steel pipeline carries hot mixture of powdered coal and coal derived oil to electric-power-generating station. Slurry is processed along way to remove sulfur, ash, and nitrogen and to recycle part of oil. System eliminates hazards and limitations associated with anticipated coal/water-slurry pipelines.

Tracing industrial heavy metal inputs to topsoils using using cadmium isotopes

NASA Astrophysics Data System (ADS)

Huang, Y.; Ma, L.; Ni, S.; Lu, H.; Liu, Z.; Zhang, C.; Guo, J.; Wang, N.

2015-12-01

Anthropogenic activities have dominated heavy metal (such as Cd, Pb, and Zn) cycling in many environments. The extent and fate of these metal depositions in topsoils, however, have not been adequately evaluated. Here, we utilize an innovative Cadmium (Cd) isotope tool to trace the sources of metal pollutants in topsoils collected from surrounding a Vanadium Titanium Magnetite smelting plant in Sichuan, China. Topsoil samples and possible pollution end-members such as fly ashes, bottom ashes, ore materials, and coal were also collected from the region surrounding the smelting plant and were analyzed for Cd isotope ratios (d114Cd relative to Cd NIST 3108). Large Cd isotope fractionation (up to 3 ‰) was observed in these industrial end-members: fly ashes possessed higher δ114Cd values ranging from +0.03 to +0.19‰; bottom fly ashes have lower δ114Cd values ranging from -0.35 to -2.46‰; and unprocessed ore and coal samples has δ114Cd value of -0.40‰. This fractionation can be attributed to the smelting processes during which bottom ashes acquired lighter Cd isotope signatures while fly ashes were mainly characterized by heavy isotope ratios, in comparison to the unprocessed ore and coal samples. Indeed, δ114Cd values of topsoils in the smelting area range from 0.29 to -0.56‰, and more than half of the soils analyzed have distinct δ114Cd values > 0‰. Cd isotopes and concentrations measured in topsoils suggested that processed materials (fly and bottom ashes from ore and coal actually used by the smelting plant) were the major source of Cd in soils. In a δ114Cd vs 1/Cd mixing diagram, the soils represent a mixture of three identified end members (fly ash, bottom ash and deep unaffected soil) with distinct Cd isotopic compositions and concentrations. Deep soils have the same δ114Cd values range as the unprocessed ore and coal, which indicated the Cd isotope fractionation did occur during evaporation and condensation processes inside the smelting plant. The signatures of fly ash end member might be even higher according to the δ114Cd increasing trend of topsoils with the increasing of Cd concentration of the topsoils. Our study suggested that δ114Cd values can be used to distinguish sources of anthropogenic Cd and to construct metal budgets in in this studying area.

Commentary an urgent need for an EPA standard for disposal of coal ash

Treesearch

A. Dennis Lemly

2014-01-01

EPA, the White House, and electric utilities are stalled in a struggle over a proposed new rule on coal ash disposal. Although this rule is long overdue, EPA now stands on the cusp of bringing forward a landmark decision that could benefit aquatic resources in the USA for decades to come and also set an important regulatory leadership example for the international...

Basic magnetic properties of bituminous coal

USGS Publications Warehouse

Alexander, C.C.; Thorpe, A.N.; Senftle, F.E.

1979-01-01

Magnetic susceptibility and other static magnetic parameters have been measured on a number of bituminous coals from various locations in the United States. The paramagnetic Curie constant correlates negatively with carbon concentration on a moisture-free basis. The major contribution to the total paramagnetism comes from the mineral matter rather than from free radicals or broken bonds. Analysis of the data indicates that the specific paramagnetism is generally lower in the mineral matter found in high-ash compared to low-ash coal. A substantial number of the coal specimens tested also had a ferromagnetic susceptibility which appeared to be associated with magnetite. Magnetite and ??-iron spherules, possibly of meteoritic or volcanic origin, were found in several specimens. ?? 1979.

Palynology, petrography and geochemistry of the Sewickley coal bed (Monongahela Group, Late Pennsylvanian), Northern Appalachian Basin, USA

USGS Publications Warehouse

Eble, C.F.; Pierce, B.S.; Grady, W.C.

2003-01-01

Forty-two bench samples of the Sewickley coal bed were collected from seven localities in the northern Appalachian Basin and analyzed palynologically, petrographically, and geochemically. The Sewickley coal bed occurs in the middle of the Pittsburgh Formation (Monongahela Group) and is of Late Pennsylvanian age. Palynologically, it is dominated by spores of tree ferns. Tree fern spore taxa in the Sewickley include Punctatisporites minutus, Punctatosporites minutus, Laevigatosporites minimus, Spinosporites exiguus, Apiculatasporites saetiger, and Thymospora spp. In fact, Punctatisporites minutus was so abundant that it had to be removed from the standard counts and recorded separately (average 73.2%). Even when Punctatisporites minutus is removed from the counts, tree fern spores still dominate a majority of the assemblages, averaging 64.4%. Among the tree fern spores identified in the Sewickley coal, Thymospora exhibits temporal and spatial abundance variation. Thymospora usually increases in abundance from the base to the top of the bed. Thymospora is also more abundant in columns that are thick (>100 cm) and low in ash yield (< 12.0%, dry basis). Calamite spores (e.g. Calamospora spp., Laevigatosporites minor, and L. vulgaris) are the next most abundant plant group represented in the Sewickley coal, averaging 20%. Contributions from all other plant groups are minor in comparison. Petrographically, the Sewickley coal contains high percentages of vitrinite (average 82.3%, mineral matter-free (mmf)), with structured forms being more common than unstructured forms. In contrast, liptinite and inertinite macerals both occur in low percentages (average 7.7% and 10.0%, respectively). Geochemically, the Sewickley coal has a moderate ash yield (average 12.4%) and high total sulfur content (average 3.4%). Four localities contained a high ash or carbonaceous shale bench. These benches, which may be coeval, are strongly dominated by tree fern spores. Unlike the lower ash benches, they contain low percentages of vitrinite, which mainly occurs as unstructured vitrinite, and higher liptinite and inertinite contents. The accumulated data suggest that the Sewickley paleomire was probably a rheotrophic, planar mire that had a consistent water cover. This is supported by the high vitrinite contents, moderate ash yields, and high total sulfur contents. The high ash and carbonaceous shale benches probably represent either periods of dryness and substrate exposure, or flooding of the mire surface, the duration of which is unknown. ?? 2003 Elsevier B.V. All rights reserved.

Filtering coal-derived oil through a filter media precoated with particles partially solubilized by said oil

DOEpatents

Rodgers, Billy R.; Edwards, Michael S.

1977-01-01

Solids such as char, ash, and refractory organic compounds are removed from coal-derived liquids from coal liquefaction processes by the pressure precoat filtration method using particles of 85-350 mesh material selected from the group of bituminous coal, anthracite coal, lignite, and devolatilized coals as precoat materials and as body feed to the unfiltered coal-derived liquid.

Ash bed level control system for a fixed-bed coal gasifier

DOEpatents

Fasching, George E.; Rotunda, John R.

1984-01-01

An ash level control system is provided which incorporates an ash level meter to automatically control the ash bed level of a coal gasifier at a selected level. The ash level signal from the ash level meter is updated during each cycle that a bed stirrer travels up and down through the extent of the ash bed level. The ash level signal is derived from temperature measurements made by thermocouples carried by the stirrer as it passes through the ash bed and into the fire zone immediately above the ash bed. The level signal is compared with selected threshold level signal to determine if the ash level is above or below the selected level once each stirrer cycle. A first counter is either incremented or decremented accordingly. The registered count of the first counter is preset in a down counter once each cycle and the preset count is counted down at a selected clock rate. A grate drive is activated to rotate a grate assembly supporting the ash bed for a period equal to the count down period to maintain the selected ash bed level. In order to avoid grate binding, the controller provides a short base operating duration time each stirrer cycle. If the ash bed level drops below a selected low level or exceeds a selected high level, means are provided to notify the operator.

Organic petrology of Paleocene Marcelina Formation coals, Paso Diablo mine, western Venezuela: Tectonic controls on coal type

USGS Publications Warehouse

Hackley, P.C.; Martinez, M.

2007-01-01

About 7??Mt of high volatile bituminous coal are produced annually from the four coal zones of the Upper Paleocene Marcelina Formation at the Paso Diablo open-pit mine of western Venezuela. As part of an ongoing coal quality study, we have characterized twenty-two coal channel samples from the mine using organic petrology techniques. Samples also were analyzed for proximate-ultimate parameters, forms of sulfur, free swelling index, ash fusion temperatures, and calorific value. Six of the samples represent incremental benches across the 12-13??m thick No. 4 bed, the stratigraphically lowest mined coal, which is also mined at the 10??km distant Mina Norte open-pit. Organic content of the No. 4 bed indicates an upward increase of woody vegetation and/or greater preservation of organic material throughout the life of the original mire(s). An upward increase in telovitrinite and corresponding decrease in detrovitrinite and inertinite illustrate this trend. In contrast, stratigraphically higher coal groups generally exhibit a 'dulling upward' trend. The generally high inertinite content, and low ash yield and sulfur content, suggest that the Paso Diablo coals were deposited in rain-fed raised mires, protected from clastic input and subjected to frequent oxidation and/or moisture stress. However, the two thinnest coal beds (both 0.7??m thick) are each characterized by lower inertinite and higher telovitrinite content relative to the rest of Paso Diablo coal beds, indicative of less well-established raised mire environments prior to drowning. Foreland basin Paleocene coals of western Venezuela, including the Paso Diablo deposit and time-correlative coal deposits of the Ta??chira and Me??rida Andes, are characterized by high inertinite and consistently lower ash and sulfur relative to Eocene and younger coals of the area. We interpret these age-delimited coal quality characteristics to be due to water availability as a function of the tectonic control of subsidence rate. It is postulated that slower subsidence rates dominated during the Paleocene while greater foreland basin subsidence rates during the Eocene-Miocene resulted from the loading of nappe thrust sheets as part of the main construction phases of the Andean orogen. South-southeastward advance and emplacement of the Lara nappes during the oblique transpressive collision of the Caribbean and South American tectonic plates in the Paleocene was further removed from the sites of peat deposition, resulting in slower subsidence rates. Slower subsidence in the Paleocene may have favored the growth of raised mires, generating higher inertinite concentrations through more frequent moisture stress. Consistently low ash yield and sulfur content would be due to the protection from clastic input in raised mires, in addition to the leaching of mineral matter by rainfall and the development of acidic conditions preventing fixation of sulfur. In contrast, peat mires of Eocene-Miocene age encountered rapid subsidence due to the proximity of nappe emplacement, resulting in lower inertinite content, higher and more variable sulfur content, and higher ash yield.

Comparing grey water versus tap water and coal ash versus perlite on growth of two plant species on green roofs.

PubMed

Agra, Har'el; Solodar, Ariel; Bawab, Omar; Levy, Shay; Kadas, Gyongyver J; Blaustein, Leon; Greenbaum, Noam

2018-08-15

Green roofs provide important ecosystem services in urban areas. In Mediterranean and other semi-arid climate regions, most perennial plants on green roofs need to be irrigated during the dry season. However, the use of freshwater in such regions is scarce. Therefore, the possibility of using grey water should be examined. Coal ash, produced primarily from the burning of coal in power plants, constitutes an environmental contaminant that should be disposed. One option is to use ash as a growing substrate for plants. Here, we compare the effects of irrigating with grey- versus tap-water and using ash versus perlite as growing substrates in green roofs. The study was conducted in northern Israel in a Mediterranean climate. The design was full factorial with three factors: water-type (grey or tap-water)×substrate-type (coal ash vs perlite)×plant species (Phyla nodiflora, Convolvulus mauritanicus or no-plant). The development of plants and the quality of drainage water along the season, as well as quality of the used substrates were monitored. Both plant species developed well under all the experimental conditions with no effect of water type or substrate type. Under all treatments, both plant species enhanced electrical conductivity (EC) and chemical oxygen demand (COD) of the drainage water. In the summer, EC and COD reached levels that are unacceptable in water and are intended to be reused for irrigation. We conclude that irrigating with grey water and using coal ash as a growth substrate can both be implemented in green roofs. The drainage from tap water as well as from grey water can be further used for irrigating the roof, but for that, COD and EC levels must be lowered by adding a sufficient amount of tap water before reusing. Copyright © 2018 Elsevier B.V. All rights reserved.

Selenium poisoning of fish by coal ash wastewater in Herrington Lake, Kentucky.

PubMed

Lemly, A Dennis

2018-04-15

Selenium pollution from the E.W. Brown Electric Generating Station was investigated in Herrington Lake, KY. Coal ash wastewater is discharged as surface water overflow from ash disposal ponds into the lake via a National Pollutant Discharge Elimination System permit issued by the Kentucky Division of Water, but the permit does not restrict or limit the amount of selenium released. Unpermitted discharges occur from seeps and drainage through leaks in ash pond dams. Together, these discharges have resulted in selenium concentrations in water, sediment, benthic macroinvertebrates, and fish that are 2-9 times the level that is toxic for fish reproduction and survival. A large proportion (12.2%, or 25 times background) of juvenile largemouth bass (Micropterus salmoides, the only species examined) exhibited spinal and/or craniofacial malformations that are consistent with selenium poisoning. Teratogenic Deformity Index values indicated a 3.05% population-level impact on the bass fishery, with total selenium-induced mortality (including pre-swimup mortality) estimated to be in excess of 25% per year. These findings confirm that coal ash discharges into Herrington Lake are contributing selenium to the Lake that is poisoning fish. Copyright © 2017 Elsevier Inc. All rights reserved.

Investigating waste rock, tailings, slag and coal ash clinker as adsorbents for heavy metals: Batch and column studies

NASA Astrophysics Data System (ADS)

Letina, D.; Letshwenyo, W. M.

2018-06-01

Wastewater from the mining industry is a concern because most of the time it contains heavy metals with concentrations above permissible levels, posing a threat to terrestrial and aquatic life. The study was conducted to evaluate the effectiveness of locally available waste materials (waste rock, tailings, coal ash clinker, and slag) generated by BCL (Ltd) mine, a copper and nickel mining and smelting company in Botswana, for removal of nickel and copper from the real mining wastewater. Batch adsorption studies were conducted to establish the adsorptive efficiency and kinetics of each media with respect to nickel and copper ions. The best media was further evaluated through fixed bed column studies at 24 and 48 h empty bed contact time. The results indicate that the percentage removal for coal ash clinker, waste rock, smelter slag and tailings was 98%, 15%, 3% and -3% with respect to copper ions, and 46%, 9%, 7% and 2% with respect to nickel ions for each media respectively. Coal ash clinker followed pseudo first order kinetic model and Langmuir isotherm model with respect to nickel ions indicating the dominance of physisorption and mono layer coverage respectively. The Langmuir separation factor (RL) was 0.37 suggesting favourable adsorption onto the media. Fixed bed column studies revealed that copper was completely retained in the bed at both 24 and 48 h contact times. In the case of nickel, removal efficiency ranged between 83% and 99% when contact time was 48 h and between 68% and 99% when the contact time was reduced to 24 h. Breakthrough was not reached after 19 bed volumes. It can be concluded that coal ash clinker is a better candidate for the removal of copper and nickel ions from mining wastewater.

Effects of solution chemistry on arsenic(V) removal by low-cost adsorbents.

PubMed

Wang, Yuru; Tsang, Daniel C W

2013-11-01

Natural and anthropogenic arsenic (As) contamination of water sources pose serious health concerns, especially for small communities in rural areas. This study assessed the applicability of three industrial byproducts (coal fly ash, lignite, and green waste compost) as the low-cost adsorbents for As(V) removal under various field-relevant conditions (dissolved oxygen, As(V)/Fe ratio, solution pH, and presence of competing species). The physico-chemical properties of the adsorbents were characterized by XRD, XRF, FT-IR, and NMR analysis. Batch experiments demonstrated that coal fly ash could provide effective As(V) removal (82.1%-95%) because it contained high content of amorphous iron/aluminium hydroxides for As(V) adsorption and dissolvable calcium minerals for calcium arsenate precipitation. However, the addition of lignite and green waste compost was found unfavourable since they hindered the As(V) removal by 10%-42% possibly due to dissolution of organic matter and ternary arsenate-iron-organic matter complexes. On the other hand, higher concentrations of dissolved iron (comparing As(V)/Fe ratios of 1:1 and 1:10) and dissolved oxygen (comparing 0.2 and 6 mg/L) only marginally enhanced the As(V) removal at pH 6 and 8. Thus, addition of dissolved iron, water aeration, or pH adjustment became unnecessary because coal fly ash was able to provide effective As(V) removal under the natural range of geochemical conditions. Moreover, the presence of low levels of background competing (0.8 or 8 mg/L of humic acid, phosphate, and silicate) imposed little influence on As(V) removal, possibly because the high adsorption capacity of coal fly ash was far from exhaustion. These results suggested that coal fly ash was a potentially promising adsorbent that warranted further investigation.

Adsorptive removal of organics from aqueous phase by acid-activated coal fly ash: preparation, adsorption, and Fenton regenerative valorization of "spent" adsorbent.

PubMed

Wang, Nannan; Hao, Linlin; Chen, Jiaqing; Zhao, Qiang; Xu, Han

2018-05-01

Raw coal fly ash was activated to an adsorbent by sulfuric acid impregnation. The activation condition, the adsorption capacity, and the regenerative valorization of the adsorbent were studied. The results show that the optimal preparation conditions of the adsorbent are [H 2 SO 4 ] = 1 mol L -1 , activation time = 30 min, the ratio of coal fly ash to acid = 1:20 (g:mL), calcination temperature = 100 °C. The adsorption of p-nitrophenol on the adsorbent accords with the pseudo-second-order kinetic equation and the adsorption rate constant is 0.089 g mg -1  min -1 . The adsorption on this adsorbent can be considered enough after 35 min, when the corresponding adsorption capacity is 1.07 mg g -1 (85.6% of p-nitrophenol removal). Compared with raw coal fly ash, the adsorbent has a stable adsorption performance at low pH range (pH = 1-6) and the adsorption of p-nitrophenol is an exothermic process. Ninety minutes is required for the regenerative valorization of saturated adsorbent by Fenton process. The regenerative valorization for this saturated adsorbent can reach 89% under the optimal proposed conditions (30 °C, pH = 3, [H 2 O 2 ] = 5.0 mmol L -1 , [Fe 2+ ] = 5.5 mmol L -1 ). Within 15 experimental runs, the adsorbent has a better and better stability with the increase of experimental runs. Finally, the mechanism of activating coal fly ash is proposed, being verified by the results of the SEM and BET test.

Immersion freezing induced by different kinds of coal fly ash: Comparing particle generation methods and measurement techniques

NASA Astrophysics Data System (ADS)

Grawe, Sarah; Augustin-Bauditz, Stefanie; Clemen, Hans-Christian; Eriksen-Hammer, Stine; Lubitz, Jasmin; Schneider, Johannes; Stratmann, Frank; Wex, Heike

2017-04-01

To date, a lot of effort has been put into the identification and characterization of atmospheric ice nucleating particles (INPs), which may influence both weather and climate. The majority of studies focuses on INPs from natural origin such as biological particles or mineral dust particles (Hoose and Möhler 2012, Murray et al. 2012). Combustion ashes, being possible sources of anthropogenic INPs, have rarely been investigated in the past. Ash particles may be emitted into the atmosphere either by the action of wind from ash deposits on the ground (bottom ash), or during the combustion process (fly ash). Two recent studies (Umo et al., 2015; Grawe et al., 2016) identified fly ash from coal combustion as the most efficient of the investigated samples (including also bottom ashes from wood and coal combustion). These results motivate the here presented study in which we investigated the immersion freezing behavior of four coal fly ash samples taken from the filters of different coal-fired power plants in Germany. A combination of two instruments was used to capture the temperature range from 0 °C to the homogeneous freezing limit at around -38 °C. Firstly, the new Leipzig Ice Nucleation Array (LINA) was used, where droplets from an ash-water suspension are pipetted onto a cooled plate. Secondly, we used the Leipzig Aerosol Cloud Interaction Simulator (LACIS; Hartmann et al., 2011), a laminar flow tube in which every droplet contains a single size-segregated ash particle. Here, it was possible to study the effect of different kinds of particle generation, i.e., atomization of an ash-water suspension, and aerosolization of dry ash material. The composition of the ash particles was investigated by means of single particle aerosol mass spectrometry and particles were sampled on filters for environmental scanning electron microscope analysis. Our measurements show that all four fly ash samples feature a similar immersion freezing behavior (ice fractions vary by a factor of 5 at most) when particles are generated via dry dispersion. Furthermore, we found that the ice nucleation ability of all samples is lowered significantly when changing from dry to wet particle generation. The aim of the study is to identify possible reasons for these observations. References: S. Grawe, S. Augustin-Bauditz, S. Hartmann, L. Hellner, J. B. C. Pettersson, A. Prager, F. Stratmann, and H. Wex, Atmos. Chem. Phys., 16, 13911-13928, 2016 S. Hartmann, D. Niedermeier, J. Voigtländer, T. Clauß, R. A. Shaw, H. Wex, A. Kiselev, and F. Stratmann, Atmos. Chem. Phys., 11, 1753-1767, 2011 C. Hoose and O. Möhler, Atmos. Chem. Phys., 12, 9817-9854, 2012 B. J. Murray, D. O'Sullivan, J. D. Atkinson, and M. E. Webb, Chem. Soc. Rev., 41, 6519-6554, 2012 N. S. Umo, B. J. Murray, M. T. Baeza-Romero, J. M. Jones, A. R. Lea-Langton, T. L. Malkin, D. O'Sullivan, L. Neve, J. M. C. Plane, and A. Williams, Atmos. Chem. Phys., 15, 5195-5210, 2015

Review of coal bottom ash and coconut shell in the production of concrete

NASA Astrophysics Data System (ADS)

Faisal, S. K.; Mazenan, P. N.; Shahidan, S.; Irwan, J. M.

2018-04-01

Concrete is the main construction material in the worldwide construction industry. High demand of sand in the concrete production have been increased which become the problems in industry. Natural sand is the most common material used in the construction industry as natural fine aggregate and it caused the availability of good quality of natural sand keep decreasing. The need for a sustainable and green construction building material is required in the construction industry. Hence, this paper presents utilization of coal bottom ash and coconut shell as partial sand replacement in production of concrete. It is able to save cost and energy other than protecting the environment. In summary, 30% usage of coal bottom ash and 25% replacement of coconut shell as aggregate replacement show the acceptable and satisfactory strength of concrete.

Leaching characteristics of fly ash from thermal power plants of Soma and Tuncbilek, Turkey.

PubMed

Baba, Alper; Kaya, Abidin

2004-02-01

Use of lignite in power generation has led to increasing environmental problems associated not only with gaseous emissions but also with the disposal of ash residues. In particular, use of low quality coal with high ash content results in huge quantities of fly ash to be disposed of. The main problem related to fly ash disposal is the heavy metal content of the residue. In this regard, experimental results of numerous studies indicate that toxic trace metals may leach when fly ash contacts water. In this study, fly ash samples obtained from thermal power plants, namely Soma and Tunçbilek, located at the west part of Turkey, were subjected to toxicity tests such as European Committee for standardization (CEN) and toxicity characteristic leaching (TCLP) procedures of the U.S. Environmental Protection Agency (U.S. EPA). The geochemical composition of the tested ash samples from the power plant show variations depending on the coal burned in the plants. Furthermore, the CEN and TCLP extraction results showed variations such that the ash samples were classified as 'toxic waste' based on TCLP result whereas they were classified as 'non-toxic' wastes based on CEN results, indicating test results are pH dependent.

Catalytic oxidation of gaseous reduced sulfur compounds using coal fly ash.

PubMed

Kastner, James R; Das, K C; Melear, Nathan D

2002-11-11

Activated carbon has been shown to oxidize reduced sulfur compounds, but in many cases it is too costly for large-scale environmental remediation applications. Alternatively, we theorized that coal fly ash, given its high metal content and the presence of carbon could act as an inexpensive catalytic oxidizer of reduced sulfur compounds for "odor" removal. Initial results indicate that coal fly ash can catalyze the oxidization of H(2)S and ethanethiol, but not dimethyl sulfide (DMS) and dimethyl disulfide (DMDS) at room temperature. In batch reactor systems, initial concentrations of 100-500 ppmv H(2)S or ethanethiol were reduced to 0-2 ppmv within 1-2 and 6-8 min, respectively. This was contrary to control systems without ash in which concentrations remained constant. Diethyl disulfide was formed from ethanethiol substantiating the claim that catalytic oxidation occurred. The presence of water increased the rate of adsorption/reaction of both H(2)S and ethanethiol for the room temperature reactions (23-25 degrees C). Additionally, in a continuous flow packed bed reactor, a gaseous stream containing an inlet H(2)S concentration of 400-500 ppmv was reduced to 200 ppmv at a 4.6s residence time. The removal efficiency remained at 50% for approximately 4.6h or 3500 reactor volumes. These results demonstrate the potential of using coal fly ash in reactors for removal of H(2)S and other reduced sulfur compounds.

²²⁶Ra, ²³²Th and ⁴⁰K radionuclides enhancement rate and dose assessment for residues of lignite-fired thermal power plants in Turkey.

PubMed

Parmaksiz, A; Arikan, P; Vural, M; Yeltepe, E; Tükenmez, I

2011-11-01

A total of 77 coal, slag and fly ash samples collected from six thermal power plants were measured by gamma-ray spectrometry. The average (226)Ra activity concentrations in coal, slag and fly ash were measured as 199.8±16.7, 380.3±21.8 and 431.5±29.0 Bq kg(-1), respectively. The average (232)Th activity concentrations in coal, slag and fly ash were measured as 32.0±2.4, 74.0±9.0 and 87.3±9.8 Bq kg(-1), respectively. The average (40)K activity concentrations in coal, slag and fly ash were found to be 152.8±12.1, 401.3±25.0 and 439.0±30.2 Bq kg(-1), respectively. The radium equivalent activities of samples varied from 147.6±8.5 to 1077.4±53.3 Bq kg(-1). The gamma and alpha index of one thermal power plant's fly ash were calculated to be 3.5 and 5 times higher than that of the reference values. The gamma absorbed dose rates were found to be higher than that of the average Earth's crust. The annual effective dose of residues measured in four thermal power plants were calculated higher than that of the permitted dose rate for public, i.e. 1 mSv y(-1).

Optimization of hydrothermal synthesis of pure phase zeolite Na-P1 from South African coal fly ashes.

PubMed

Musyoka, Nicholas M; Petrik, Leslie F; Gitari, Wilson M; Balfour, Gillian; Hums, Eric

2012-01-01

This study was aimed at optimizing the synthesis conditions for pure phase zeolite Na-P1 from three coal fly ashes obtained from power stations in the Mpumalanga province of South Africa. Synthesis variables evaluated were: hydrothermal treatment time (12-48 hours), temperature (100-160°C) and varying molar quantities of water during the hydrothermal treatment step (H(2)O:SiO(2) molar ratio ranged between 0-0.49). The optimum synthesis conditions for preparing pure phase zeolite Na-P1 were achieved when the molar regime was 1 SiO(2): 0.36 Al(2)O(3): 0.59 NaOH: 0.49 H(2)O and ageing was done at 47°C for 48 hours. The optimum hydrothermal treatment time and temperature was 48 hours and 140°C, respectively. Fly ashes sourced from two coal-fired power plants (A, B) were found to produce nearly same high purity zeolite Na-P1 under identical conditions whereas the third fly ash (C) lead to a low quality zeolite Na-P1 under these conditions. The cation exchange capacity for the high pure phase was found to be 4.11 meq/g. These results highlight the fact that adjustment of reactant composition and presynthesis or synthesis parameters, improved quality of zeolite Na-P1 can be achieved and hence an improved potential for application of zeolites prepared from coal fly ash.

Remedial Investigation Report on Chestnut Ridge Operable Unit 2 (Filled Coal Ash Pond/Upper McCoy Branch) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. Volume 1. Main Text

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1994-08-01

This document is a report on the remedial investigation (RI) of Chestnut Ridge Operable Unit (OU) 2 at the Oak Ridge Y-12 Plant. Chestnut Ridge OU 2 consists of Upper McCoy Branch (UMB), the Filled Coal Ash Pond (FCAP), and the area surrounding the Sluice Channel formerly associated with coal ash disposal in the FCAP. Chestnut Ridge OU 2 is located within the U.S. Department of Energy`s (DOE`s) Oak Ridge Reservation in Anderson County, Tennessee, approximately 24 miles west of Knoxville. The pond is an 8.5-acre area on the southern slope of Chestnut Ridge, 0.5 mile south of the mainmore » Y-12 Plant and geographically separated from the Y-12 Plant by Chestnut Ridge. The elevation of the FCAP is {approximately} 950 ft above mean sea level (msl), and it is relatively flat and largely vegetated. Two small ponds are usually present at the northeast and northwest comers of the FCAP. The Sluice Channel Area extends {approximately}1000 ft from the northern margin of the FCAP to the crest of Chestnut Ridge, which has an elevation of {approximately}1100 ft above msl. The Sluice Channel Area is largely vegetated also. McCoy Branch runs from the top of Chestnut Ridge across the FCAP into Rogers Quarry and out of the quarry where it runs a short distance into Milton Hill Lake at McCoy Embayment, termed UMB. The portion south of Rogers Quarry, within Chestnut Ridge OU 4, is termed Lower McCoy Branch. The DOE Oak Ridge Y-12 Plant disposed of coal ash from its steam plant operations as a slurry that was discharged into an ash retention impoundment; this impoundment is the FCAP. The FCAP was built in 1955 to serve as a settling basin after coal ash slurried over Chestnut Ridge from the Y-12 Plant. The FCAP was constructed by building an earthen dam across the northern tributary of McCoy Branch. The dam was designed to hold 20 years of Y-12 steam plant ash. By July 1967, ash had filled up the impoundment storage behind the dam to within 4 ft of the top.« less

INVESTIGATION OF PRIMARY FINE PARTICULATE MATTER FROM COAL COMBUSTION BY COMPUTER-CONTROLLED SCANNING ELECTRON MICROSCOPY

EPA Science Inventory

The particle size distributions, morphologies, and chemical composition distributions of 14 coal fly ash (CFA) samples produced by the combustion of four western U.S. coals (two subbituminous, one lignite, and one bituminous) and three eastern U.S. coals (all bituminous) have bee...

Coal Research

NASA Technical Reports Server (NTRS)

1986-01-01

Coal slurries are "clean" pulverized coal mixed with oil or water. Significant fuel savings can be realized when using coal slurries. Advanced Fuels Technology (AFT) utilized a COSMIC program, (Calculation of Complex Chemical Equilibrium Compositions), which provides specific capabilities for determining combustion products. The company has developed a cleaning process that removes much of the mineral sulphur and ash from the coals.

Evaluation of coalbed gas potential of the Seelyville Coal Member, Indiana, USA

USGS Publications Warehouse

Drobniak, A.; Mastalerz, Maria; Rupp, J.; Eaton, N.

2004-01-01

The Seelyville Coal Member of the Linton Formation in Indiana potentially contains 0.03 trillion m3 (1.1 TCF) of coalbed gas. The gas content determined by canister desorption technique ranges from 0.5 to 5.7 cm3/g on dry ash free basis (15.4 to 182.2 scf/ton). The controls on gas content distribution are complex, and cannot be explained by the coal rank alone. Ash content and the lithology of the overlying strata, among other factors, may influence this distribution. ?? 2004 Elsevier B.V. All rights reserved.

Effects of detrital influx in the Pennsylvanian Upper Freeport peat swamp

USGS Publications Warehouse

Ruppert, L.F.; Stanton, R.W.; Blaine, Cecil C.; Eble, C.F.; Dulong, F.T.

1991-01-01

Quartz cathodoluminescence properties and mineralogy of three sets of samples and vegetal and/ or miospore data from two sets of samples from the Upper Freeport coal bed, west-central Pennsylvania, show that detrital influence from a penecontemporaneous channel is limited to an area less than three km from the channel. The sets of samples examined include localities of the coal bed where (1) the coal is thin, split by partings, and near a penecontemporaneous fluvial channel, (2) the coal is relatively thick and located approximately three km from the channel, and (3) the coal is thick and located approximately 12 km from the channel. Samples from locality 1 (nearest the channel) have relatively high-ash yields (low-temperature ash average = 27.3% on a pyrite- and calcite-free basis) and high proportions of quartz and clay minerals. The quartz is primarily detrital, as determined by cathodoluminescent properties, and the ratio of kaolinite to illite is low. In addition, most of the plant remains and miospores indicate peat-forming plants that required low nutrient levels for growth. In contrast, samples from localities 2 and 3, from the more interior parts of the bed, contained predominantly authigenic quartz grains nd yielded low-temperature ash values of less than 14% on a pyrite- and calcite-free basis. The low-temperature ash contains low concentrations of quartz and clay minerals and the ratio of kaolinite to illite is relatively high. Although intact core was not available for paleobotanical analyses, another core collected within 1 km from locality 3 contained plant types interpreted to have required high nutrient levels for growth. These data indicate that mineral formation is dominated by authigenic processes in interior parts of the coal body. Some of the authigenic quartz may have been derived from herbaceous ferns as indicated by patterns in the palynological and paleobotanical data. In contrast, detrital processes appeared to be limited to in areas directly adjacent to the penecontemporaneous channel where the coal bed is high in ash, split by mineral-rich partings, and of little or no economic value. ?? 1991.

Relationships among macerals, minerals, miospores and paleoecology in a column of Redstone coal (Upper Pennsylvanian) from north-central West Virginia (U.S.A.)

USGS Publications Warehouse

Grady, W.C.; Eble, C.F.

1990-01-01

Two distinct paleoenvironments are represented in vertical succession in a column of Redstone coal in north-central West Virginia as indicated by a study of 37 consecutive 3-cm (0.1 ft) increments analyzed for ash yield, petrographic composition, low-temperature ash mineralogy and palynomorph abundances. Abundance profiles were constructed for ash, 12 petrographic components, 3 minerals and 5 miospore assemblages. The profiles and calculated correlation coefficients show close relationships between several constituents. Components that increased in abundance upward in the coal bed were a collinite type > 50 microns in thickness, cutinite, and miospores affiliated with calamites, herbaceous lycopods, cordaites and herbaceous ferns. Components that decreased in abundance upward were a collinite type 50 ??m in thickness, cutinite, calamite and cordaite miospores and kaolinite. Significant correlations occurred between ash yield and the collinite types > 50 and < 50 ??m in thickness but no significant correlation was found between ash yield and total vitrinite-group content. This is interpreted to show that division of vitrinite macerals by size is important in petrographic paleoenvironmental studies. Paleoecologic interpretations based upon these correlations suggest that two distinct, planar, probably topogenous paleoecologic environments are represented in this column of the Redstone coal. The lower two-thirds of the coal bed was interpreted to have accumulated in a planar swamp in which significant introduction of detrital or dissolved mineral matter, and significant anaerobic and moderate oxidative degradation of the peat occurred. The flora of this paleoenvironment was dominated by tree ferns. The paleoenvironment during accumulation of the upper one-third of the coal bed was also interpreted to have been a planar swamp, but one in which moderate to low introduction of detrital or dissolved mineral matter, and minor anaerobic and oxidative degradation of the peat occurred. The dominant flora of this paleoenvironment consisted mainly of calamites with fewer cordaites and herbaceous ferns. This study shows that valuable paleoecologic information may be obtained by sampling closely spaced vertical increments. No mixing of detrital sediments with the peat was observed in coal layers immediately adjacent to the parting or the overlying sandstone unit. ?? 1990.

Removal of Pb(II) from wastewater using Al2O3-NaA zeolite composite hollow fiber membranes synthesized from solid waste coal fly ash.

PubMed

Zhu, Li; Ji, Jiayou; Wang, Shulin; Xu, Chenxi; Yang, Kun; Xu, Man

2018-09-01

Al 2 O 3 -NaA zeolite composite hollow fiber membranes were successfully fabricated via hydrothermal synthesis by using industrial solid waste coal fly ash and porous Al 2 O 3 hollow fiber supports. The as-synthesized Al 2 O 3 -NaA zeolite composite hollow fiber membranes were then characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The hollow fiber membranes were used to remove lead ions (Pb(II), 50 mg L -1 ) from synthetic wastewater with a removal efficiency of 99.9% at 0.1 MPa after 12 h of filtration. This study showed that the Al 2 O 3 -NaA zeolite composite hollow fiber membranes (the pore size of the membrane was about 0.41 nm in diameter) synthesized from coal fly ash could be efficiently used for treating low concentration Pb(II) wastewater. It recycled solid waste coal fly ash not only to solve its environment problems, but also can produce high-value Al 2 O 3 -NaA zeolite composite hollow fiber membranes for separation application in treating wastewater containing Pb(II). Copyright © 2018 Elsevier Ltd. All rights reserved.

Greatly increased use of fly ash in hydraulic cement concrete (HCC) for pavement layers and transportation structures - volume I.

DOT National Transportation Integrated Search

2012-03-01

The purpose of this phase is to evaluate the past, current and future trends of use of fly ash in concrete and restrictions to its use. The American Coal Ash Association (ACAA) conducts an annual survey of fly ash production and use. Typically on an ...

Moist caustic leaching of coal

DOEpatents

Nowak, Michael A.

1994-01-01

A process for reducing the sulfur and ash content of coal. Particulate coal is introduced into a closed heated reaction chamber having an inert atmosphere to which is added 50 mole percent NaOH and 50 mole percent KOH moist caustic having a water content in the range of from about 15% by weight to about 35% by weight and in a caustic to coal weight ratio of about 5 to 1. The coal and moist caustic are kept at a temperature of about 300.degree. C. Then, water is added to the coal and caustic mixture to form an aqueous slurry, which is washed with water to remove caustic from the coal and to produce an aqueous caustic solution. Water is evaporated from the aqueous caustic solution until the water is in the range of from about 15% by weight to about 35% by weight and is reintroduced to the closed reaction chamber. Sufficient acid is added to the washed coal slurry to neutralize any remaining caustic present on the coal, which is thereafter dried to produce desulfurized coal having not less than about 90% by weight of the sulfur present in the coal feed removed and having an ash content of less than about 2% by weight.

Quality of Selected Hungarian Coals

USGS Publications Warehouse

Landis, E.R.; Rohrbacher, T.J.; Gluskoter, H.J.; Fodor, B.; Gombar, G.

2007-01-01

As part of a program conducted jointly by the U.S. Geological Survey and the Hungarian Geological Survey under the auspices of the United States-Hungarian Science and Technology Fund, a total of 39 samples from five coal mines in Hungary were selected for analysis. The mine areas sampled represent most of the coal mined recently in Hungary. Almost all the coal is used to generate electricity. Coals from the five mines (four underground, one surface) reflect differences in age, depositional setting, organic and inorganic components of the original sediments, and deformational history. Classified according to the ranking system of the American Society for Testing and Materials, the coals range in rank from lignite B (Pliocene[?] coals) to high volatile A bituminous (Jurassic coals). With respect to grade classification, based on seam-weighted averages of moisture, ash, and sulfur contents: (1) all contain high moisture (more than 10 percent), (2) all except the Eocene coals are high (more than 15 percent) in ash yield, and (3) two (Jurassic and Eocene coals) are high in sulfur (more than 3 percent) and three (Cretaceous, Miocene, and Pliocene coals) have medium sulfur contents (1 to 3 percent). Average heat values range from 4,000 to 8,650 British thermal units per pound.

Differentiation of volcanic ash-fall and water-borne detrital layers in the Eocene Senakin coal bed, Tanjung Formation, Indonesia

USGS Publications Warehouse

Ruppert, L.F.; Moore, T.A.

1993-01-01

The Sangsang deposit of the Eocene Senakin coal bed, Tanjung Formation, southeastern Kalimantan, Indonesia, contains 11 layers, which are thin ( 70%). These layers are characterized by their pelitic macroscopic texture. Examination of eight of the layers by scanning-electron microscopy, energy-dispersive X-ray, and X-ray diffraction analyses show that they are composed primarily of fairly well-crystallized kaolinite, much of which is vermicular. Accessory minerals include abundant Ti oxide, rare-earth element-rich Ca and A1 phosphates, quartz that luminescences in the blue color range, and euhedral to subhedral pyroxene, hornblende, zircon, and sanidine. Although this mineral suite is suggestive of volcanic ash-fall material, only the four pelitic layers in the middle of the bed are thought to be solely derived from volcanic ash-falls on the basis of diagnostic minerals, replaced glass shards, and lithostratigraphic relationships observed in core and outcrop. The three uppermost pelitic layers contain octahedral chromites, some quartz grains that luminesce in teh orange color range, and some quartz grains that contain two-phase fluid inclusions. These layers are interpreted to be derived from a combination of volcanic ash-fall material and hydrologic transport of volcaniclastic sediment. In contrast, the lowermost pelitic layer, which contains large, rounded FeMg-rich chromites, is thought to have been dominantly deposited by water. The source of the volcanic ash-fall material may have been middle Tertiary volcanism related to plate tectonic activity between Kalimantan and Sulawesi. The volcanic ash was deposited in sufficient amounts to be preserved as layers within the coal only in the northern portions of the Senakin region: the southern coal beds in the region do not contain pelitic layers. ?? 1993.

Utilization of blended fluidized bed combustion (FBC) ash and pulverized coal combustion (PCC) fly ash in geopolymer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chindaprasirt, Prinya; Rattanasak, Ubolluk, E-mail: ubolluk@buu.ac.t

2010-04-15

In this paper, synthesis of geopolymer from fluidized bed combustion (FBC) ash and pulverized coal combustion (PCC) fly ash was studied in order to effectively utilize both ashes. FBC-fly ash and bottom ash were inter-ground to three different finenesses. The ashes were mixed with as-received PCC-fly ash in various proportions and used as source material for synthesis of geopolymer. Sodium silicate (Na{sub 2}SiO{sub 3}) and 10 M sodium hydroxide (NaOH) solutions at mass ratio of Na{sub 2}SiO{sub 3}/NaOH of 1.5 and curing temperature of 65 deg. C for 48 h were used for making geopolymer. X-ray diffraction (XRD), scanning electronmore » microscopy (SEM), degree of reaction, and thermal gravimetric analysis (TGA) were performed on the geopolymer pastes. Compressive strength was also tested on geopolymer mortars. The results show that high strength geopolymer mortars of 35.0-44.0 MPa can be produced using mixture of ground FBC ash and as-received PCC-fly ash. Fine FBC ash is more reactive and results in higher degree of reaction and higher strength geopolymer as compared to the use of coarser FBC ash. Grinding increases reactivity of ash by means of increasing surface area and the amount of reactive phase of the ash. In addition, the packing effect due to fine particles also contributed to increase in strength of geopolymers.« less

Bottom ash test section evaluation Erwinville, LA.

DOT National Transportation Integrated Search

2009-02-01

Bottom ash is a by-product of the energy industry and the residual of burning coal in a kiln : firing process. Bottom ash is black and the consistency of coarse sand with gravel clinker : traces. The product is used in other states as embankment mate...

Why is Coal Ash of Concern and How to Assess Potential Impacts?

EPA Science Inventory

EPA's new test methods - the leaching environmental assessment framework (LEAF) are discussed including how they have been used to evaluate fly ash and scrubber residues. Work to evaluate high-volume encapsulated use of fly ash in cementitious material is also described.

Development of a standard operating procedure for analysis of ammonia concentrations in coal fly ash.

DOT National Transportation Integrated Search

2015-04-01

Research was performed to support the development and recommendation of a standard operating : procedure (SOP) for analyzing the ammonia content in fly ash intended for use in concrete. A review : of existing ash producers found that several differen...

Process for the recovery of alumina from fly ash

DOEpatents

Murtha, M.J.

1983-08-09

An improvement in the lime-sinter process for recovering alumina from pulverized coal fly ash is disclosed. The addition of from 2 to 10 weight percent carbon and sulfur to the fly ash-calcium carbonate mixture increase alumina recovery at lower sintering temperatures.

Combustion characteristics and retention-emission of selenium during co-firing of torrefied biomass and its blends with high ash coal.

PubMed

Ullah, Habib; Liu, Guijian; Yousaf, Balal; Ali, Muhammad Ubaid; Abbas, Qumber; Zhou, Chuncai

2017-12-01

The combustion characteristics, kinetic analysis and selenium retention-emission behavior during co-combustion of high ash coal (HAC) with pine wood (PW) biomass and torrefied pine wood (TPW) were investigated through a combination of thermogravimetric analysis (TGA) and laboratory-based circulating fluidized bed combustion experiment. Improved ignition behavior and thermal reactivity of HAC were observed through the addition of a suitable proportion of biomass and torrefied. During combustion of blends, higher values of relative enrichment factors in fly ash revealed the maximum content of condensing volatile selenium on fly ash particles, and depleted level in bottom ash. Selenium emission in blends decreased by the increasing ratio of both PW and TPW. Higher reductions in the total Se volatilization were found for HAC/TPW than individual HAC sample, recommending that TPW have the best potential of selenium retention. The interaction amongst selenium and fly ash particles may cause the retention of selenium. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mercury retention by fly ashes from coal combustion: Influence of the unburned carbon content

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lopez-Anton, M.A.; Diaz-Somoano, M.; Martinez-Tarazona, M.R.

2007-01-31

The objective of this study was to evaluate the effect of unburned carbon particles present in fly ashes produced by coal combustion on mercury retention. To achieve this objective, the work was divided into two parts. The aim of the first part of the study was to estimate the amount of mercury captured by the fly ashes during combustion in power stations and the relationship of this retention to the unburned carbon content. The second part was a laboratory-scale study aimed at evaluating the retention of mercury concentrations greater than those produced in power stations by fly ashes of differentmore » characteristics and by unburned carbon particles. From the results obtained it can be inferred that the unburned carbon content is not the only variable that controls mercury capture in fly ashes. The textural characteristics of these unburned particles and of other components of fly ashes also influence retention.« less

Utilization of coal fly ash as a slow-release granular medium for soil improvement.

PubMed

Yoo, Jeong Gun; Jo, Young Min

2003-01-01

This work proposes a new potential application of waste coal fly ash as a K fertilizer support. Fly ash was reacted with KOH to facilitate the impregnation of K as well as to enhance the bonding force. In particular, the applied process resulted in a significant slow-releasing characteristic of fertilizer elements. To examine the effect of K impregnation, a few detailed leaching tests were carried out in terms of process variables such as reaction time and temperature, sintering time and temperature, and KOH concentration. The current experiment presented an optimum preparation condition that is competitive with conventional commercial fertilizers. The manufactured ash fertilizers inhibited release of the K elements. It was also found through the continuous leaching test with pure water that the ash fertilizer had excellent moisture absorbability. However, the effects of some trace elements in fly ash on soil health and crop productivity as well as environmental considerations need to be established with long-term studies.

Rocky Mountain Tertiary coal-basin models and their applicability to some world basins

USGS Publications Warehouse

Flores, R.M.

1989-01-01

Tertiary intermontane basins in the Rocky Mountain region of the United States contain large amounts of coal resources. The first major type of Tertiary coal basin is closed and lake-dominated, either mud-rich (e.g., North Park Basin, Colorado) or mud plus carbonate (e.g., Medicine Lodge Basin, Montana), which are both infilled by deltas. The second major type of Tertiary coal basin is open and characterized by a preponderance of sediments that were deposited by flow-through fluvial systems (e.g., Raton Basin, Colorado and New Mexico, and Powder River Basin, Wyoming and Montana). The setting for the formation of these coals varies with the type of basin sedimentation, paleotectonism, and paleoclimate. The mud-rich lake-dominated closed basin (transpressional paleotectonism and warm, humid paleoclimate), where infilled by sandy "Gilbert-type" deltas, contains thick coals (low ash and low sulfur) formed in swamps of the prograding fluvial systems. The mud- and carbonate-rich lake-dominated closed basin is infilled by carbonate precipitates plus coarse-grained fan deltas and fine-grained deltas. Here, thin coals (high ash and high sulfur) formed in swamps of the fine-grained deltas. The coarse-clastic, open basins (compressional paleotectonism and warm, paratropical paleoclimate) associated with flow-through fluvial systems contain moderately to anomalously thick coals (high to low ash and low sulfur) formed in swamps developed in intermittently abandoned portions of the fluvial systems. These coal development patterns from the Tertiary Rocky Mountain basins, although occurring in completely different paleotectonic settings, are similar to that found in the Tertiary, Cretaceous, and Permian intermontane coal basins in China, New Zealand, and India. ?? 1989.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nelson, W.J.; DeMaris, P.J.; Bauer, R.A.

One of the largest deposits of low-sulfur coal in the Illinois Basin is in the so-called Hornsby District of Christian, Macoupin, and Montgomery Counties. An estimated resource of 1.17 billion tons of Herrin (No. 6) Coal, containing less than 2.5% sulfur, occurs here. Although the Hornsby deposit is thick, lies at moderate depth, and is close to market and labor supply, it has been barely touched by mining. The primary deterrent to mining this high-quality product has been fear of unstable roof conditions. Low-sulfur Hornsby coal contains about 1.5% less ash and 2% more moisture than does adjacent high-sulfur coal.more » The lower ash content probably reflects scarcity of pyrite. The reason for the difference in moisture content is unknown. High- and low-sulfur coal are nearly identical in heating value.« less

Characterization of feed coal and coal combustion products from power plants in Indiana and Kentucky

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brownfield, M.E.; Affolter, R.H.; Cathcart, J.D.

1999-07-01

The US Geological Survey, Kentucky Geological Survey, and the University of Kentucky Center for Applied Energy Research are collaborating with Indiana and Kentucky utilities to determine the physical and chemical properties of feed coal and coal combustion products (CCP) from three coal-fired power plants. These three plants are designated as Units K1, K2, and I1 and burn high-, moderate-, and low-sulfur coals, respectively. Over 200 samples of feed coal and CCP were analyzed by various chemical and mineralogical methods to determine mode of occurrence and distribution of trace elements in the CCP. Generally, feed coals from all 3 Units containmore » mostly well-crystallized kaolinite and quartz. Comparatively, Unit K1 feed coals have higher amounts of carbonates, pyrite and sphalerite. Unit K2 feed coals contain higher kaolinite and illite/muscovite when compared to Unit K1 coals. Unit I1 feed coals contain beta-form quartz and alumino-phosphates with minor amounts of calcite, micas, anatase, and zircon when compared to K1 and K2 feed coals. Mineralogy of feed coals indicate that the coal sources for Units K1 and K2 are highly variable, with Unit K1 displaying the greatest mineralogic variability; Unit I1 feed coal however, displayed little mineralogic variation supporting a single source. Similarly, element contents of Units K1 and K2 feed coals show more variability than those of Unit I1. Fly ash samples from Units K1 and K2 consist mostly of glass, mullite, quartz, and spines group minerals. Minor amounts of illite/muscovite, sulfates, hematite, and corundum are also present. Spinel group minerals identified include magnetite, franklinite, magnesioferrite, trevorite, jacobisite, and zincochromite. Scanning Electron Microscope analysis reveals that most of the spinel minerals are dendritic intergrowths within aluminum silicate glass. Unit I1 fly ash samples contain glass, quartz, perovskite, lime, gehlenite, and apatite with minor amounts of periclase, anhydrite, carbonates, pyroxenes, and spinels. The abundant Ca mineral phases in the Unit I1 fly ashes are attributed to the presence of carbonate, clay and phosphate minerals in the coal.« less

40 CFR 434.23 - Effluent limitations guidelines representing the degree of effluent reduction attainable by...

Code of Federal Regulations, 2011 CFR

2011-07-01

... available technology economically achievable if discharges from such point sources normally exhibit a pH of... discharges from such point sources normally exhibit a pH equal to or greater than 6.0 prior to treatment: BAT... concentration or quality of pollutants which may be discharged by any existing coal preparation plant and coal...

40 CFR 434.23 - Effluent limitations guidelines representing the degree of effluent reduction attainable by...

Code of Federal Regulations, 2010 CFR

2010-07-01

... available technology economically achievable if discharges from such point sources normally exhibit a pH of... discharges from such point sources normally exhibit a pH equal to or greater than 6.0 prior to treatment: BAT... concentration or quality of pollutants which may be discharged by any existing coal preparation plant and coal...

Block coals from Indiana: Inferences on changing depositional environment

USGS Publications Warehouse

Mastalerz, Maria; Padgett, P.L.; Eble, C.F.

2000-01-01

Significant differences in coal petrography, palynology and coal quality were found between the Lower Block and Upper Block Coal Members (Brazil Formation, Pennsylvanian) in Daviess County, Indiana. The Lower Block Coal Member ranges in thickness from 51 to 74 cm and the Upper Block Coal Member ranges from 20 to 65 cm. Average sulfur content and ash yield of the Lower Block coal (0.98%, 7.65%) are lower than in the Upper Block coal. Megascopically, the coals show distinct differences. The Lower Block is a banded coal with numerous thin fusain horizons and a thin clay parting in the lower third of the seam. The Upper Block coal has a dulling-upward trend, with a bright clarain found at the base that grades into a clarain and then into a durain in the upper portion of the seam. Vitrinite content of the Lower Block coal ranges from 63% to 78%, with the highest vitrinite content found in the middle portion of the seam. In the Upper Block coal, vitrinite content ranges from 40% to 83%, with the highest values found in the lower part of the seam. Ash yield is higher in the upper part of the Upper Block coal, reaching up to 40%. The Lower Block coal is dominated by lycopod trees and tree ferns. The Upper Block coal shows marked differences in spore assemblages between lower and upper parts of the seam. The lower half is dominated by large lycopod trees and tree ferns, similar to the Lower Block coal. The upper half is dominated by small lycopods, mainly Densosporites and Radiizonates. These differences between the Lower Block and Upper Block Coal Members are significant correlation tools applicable to mining exploration and chronostratigraphy. (C) 2000 Elsevier Science B.V. All rights reserved.Significant differences in coal petrography, palynology and coal quality were found between the Lower Block and Upper Block Coal Members (Brazil Formation, Pennsylvanian) in Daviess County, Indiana. The Lower Block Coal Member ranges in thickness from 51 to 74 cm and the Upper Block Coal Member ranges from 20 to 65 cm. Average sulfur content and ash yield of the Lower Block coal (0.98%, 7.65%) are lower than in the Upper Block coal. Megascopically, the coals show distinct differences. The Lower Block is a banded coal with numerous thin fusain horizons and a thin clay parting in the lower third of the seam. The Upper Block coal has a dulling-upward trend, with a bright clarain found at the base that grades into a clarain and then into a durain in the upper portion of the seam. Vitrinite content of the Lower Block coal ranges from 63% to 78%, with the highest vitrinite content found in the middle portion of the seam. In the Upper Block coal, vitrinite content ranges from 40% to 83%, with the highest values found in the lower part of the seam. Ash yield is higher in the upper part of the Upper Block coal, reaching up to 40%. The Lower Block coal is dominated by lycopod trees and tree ferns. The Upper Block coal shows marked differences in spore assemblages between lower and upper parts of the seam. The lower half is dominated by large lycopod trees and tree ferns, similar to the Lower Block coal. The upper half is dominated by small lycopods, mainly Densosporites and Radiizonates. These differences between the Lower Block and Upper Block Coal members are significant correlation tools applicable to mining exploration and chronostratigraphy.

Coal fly ash based carbons for SO2 removal from flue gases.

PubMed

Rubio, B; Izquierdo, M T

2010-07-01

Two different coal fly ashes coming from the burning of two coals of different rank have been used as a precursor for the preparation of steam activated carbons. The performance of these activated carbons in the SO(2) removal was evaluated at flue gas conditions (100 degrees C, 1000 ppmv SO(2), 5% O(2), 6% H(2)O). Different techniques were used to determine the physical and chemical characteristics of the samples in order to explain the differences found in their behaviour. A superior SO(2) removal capacity was shown by the activated carbon obtained using the fly ash coming from a sub-bituminous-lignite blend. Experimental results indicated that the presence of higher amount of certain metallic oxides (Ca, Fe) in the carbon-rich fraction of this fly ash probably has promoted a deeper gasification in the activation with steam. A more suitable surface chemistry and textural properties have been obtained in this case which explains the higher efficiency shown by this sample in the SO(2) removal. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Nitration of benzo[a]pyrene adsorbed on coal fly ash particles by nitrogen dioxide: role of thermal activation.

PubMed

Kristovich, Robert L; Dutta, Prabir K

2005-09-15

Nitration of benzo[a]pyrene (BaP) by nitrogen dioxide (NO2) adsorbed on the surface of thermally activated coal fly ash and model aluminosilicate particles led to the formation of nitrobenzo[a]pyrenes as verified by extraction and gas chromatography/mass spectrometry (GC/MS). In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) was utilized to follow the nitration reaction on the surface of zeolite Y. Nitrobenzo[a]pyrene formation was observed along with the formation of nitrous acid and nitrate species. The formation of the BaP radical cation was also observed on thermally activated aluminosilicate particles by electron spin resonance (ESR) spectroscopy. On the basis of GC/MS, DRIFTS, and ESR spectroscopy results, a mechanism of nitration involving intermediate BaP radical cations generated on thermally activated aluminosilicate particles is proposed. These observations have led to the hypothesis that nitration of adsorbed polyaromatic hydrocarbons on coal fly ash by reaction with nitrogen oxides can occur in the smokestack, but with the aging of the fly ash particles, the extent of the nitration reaction will be diminished.

Process for the removal of radium from acidic solutions containing same

DOEpatents

Scheitlin, F.M.

The invention is a process for the removal of radium from acidic aqueous solutions. In one aspect, the invention is a process for removing radium from an inorganic-acid solution. The process comprises contacting the solution with coal fly ash to effect adsorption of the radium on the ash. The radium-containing ash then is separated from the solution. The process is simple, comparatively inexpensive, and efficient. High radium-distribution coefficients are obtained even at room temperature. Coal fly ash is an inexpensive, acid-resistant, high-surface-area material which is available in large quantities throughout the United States. The invention is applicable, for example, to the recovery of /sup 226/Ra from nitric acid solutions which have been used to leach radium from uranium-mill tailings.

Magnetic susceptibility mapping of fly ash in soil samples near a coal-burning power plant in Pointe Coupee Parish, Louisiana.

NASA Astrophysics Data System (ADS)

Elhelou, O.; Richter, C.

2015-12-01

Atmospheric deposition of pollutants is a major health and environmental concern. In a 2010 study, the CATF attributed over 13,000 deaths each year to fly ash and other fine particles emitted by U.S. coal-burning power plants. The magnetic properties of fly ash allows for mapping an area suspect of PM pollution faster and more efficiently than by conducting chemical analysis as the former alternative. The objective of this study is to detect the presence of magnetic particles related to the migration of fly ash from a nearby coal power plant over parts of Pointe Coupee Parish, LA. This is based on the idea that the fly ash that is released into the atmosphere during the coal burning process contains heavy metals and magnetic particles in the form of ferrospheres, which can be used to trace back to the source. Maps of the top and sub soil were generated to differentiate the magnetic susceptibility values of the heavy metals potentially attributed to the migration and settling of fly ash onto the surface from any pre-existing or naturally occurring heavy metals in the sub soil. A 60 km2 area in Pointe Coupee Parish was investigated in approximately 0.5 km2 subsets. The area in Pointe Coupee Parish, LA was selected because land use is predominantly rural with the Big Cajun II power plant as the main contributor for air borne contaminants. Samples of fly ash obtained directly from the source below one of the power plant's precipitators were also analyzed to verify the field and laboratory analysis. Contour maps representing the spatial distribution of fly ash over Pointe Coupee, LA, along with histograms of magnetic susceptibility values, and chemical analysis all indicate a correlation between the proximity to the power plant and the predominant wind direction. Acquisition curves of the isothermal remnant magnetization demonstrate the presence of predominantly low coercivity minerals (magnetite) with a small amount of a high-coercivity phase. The microstructure of the magnetic fractions of the fly ash along with select top and sub soil samples were observed using a reflective light microscope for identifying and confirming the presence of ferrospheres associated with fly ash. Chemical analyses of select samples revealed their heavy metal composition and the correlation with their SIRM and low field mass susceptibility values.

Fundamental study of ash formation and deposition: Effect of reducing stoichiometry. Final report, April 1, 1993--June 30, 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bool, L.E. III; Helble, J.J.; Shah, N.

1995-09-01

The technical objectives of this project are: (1) To identify the partitioning of inorganic coal constituents among vapor, submicron fume, and fly ash products generated during the combustion of pulverized coal under a variety of combustion conditions. Fuel lean and fuel rich combustion conditions are considered. (2) To identify and quantify the fundamental processes by which the transformations of minerals and organically-associated inorganic species occur. Emphasis is placed on identifying any changes that occur as a result of combustion under sub-stoichiometric combustion conditions. (3) To incorporate the effects of combustion stoichiometry into an Engineering Model for Ash Formation.

Exploring metal detoxification and accumulation potential during vermicomposting of Tea factory coal ash: sequential extraction and fluorescence probe analysis

NASA Astrophysics Data System (ADS)

Goswami, Linee; Pratihar, Sanjay; Dasgupta, Suman; Bhattacharyya, Pradip; Mudoi, Pronab; Bora, Jayanta; Bhattacharya, Satya Sundar; Kim, Ki Hyun

2016-07-01

Metal contamination from coal ashes (CAs) is widely recognized as a significant environmental concern. To learn more about metal detoxification and accumulation potential of earthworm species, metal-rich tea factory coal ashes (TFCA) were fed to Eisenia fetida and Lampito mauritii by employing a fluorescent tag detection method. Fascinatingly, on feeding fluorescence probed Zn and Cd along with cow dung to Eisenia fetida, the detection of the gut-proteins with a molecular mass higher than 100 kDa was a distinct evidence of metal binding. Significant increases were observed in the content of humified organic C [humic acid (HAC) and fulvic acid C (FAC)] and degree of humification during vermicomposting. Concurrently, considerably large amount of toxic metals (Cr, Cd, Pb, and Zn) was transformed from exchangeable to recalcitrant (organic matter and mineral bound) fractions. Moreover, total metal concentrations were reduced with high removal efficiency upon vermicomposting.

Alkali borosilicate glass by fly ash from a coal-fired power plant.

PubMed

Park, Jong Soo; Taniguchi, Shoji; Park, Young Jun

2009-01-01

The possibility of using coal fly ash as a silica source for alkali borosilicate glass was investigated. Alkali borosilicate glasses were prepared from the coal fly ash mixed with 30 wt.% reagents composed of Na(2)O and B(2)O(3) by susceptor-induction heating. Their densities ranged from 2.24 to 2.55 g cm(-3) and decreased as the amount of B(2)O(3) addition increased. However, the Vickers microhardness showed a different tendency with the density since the glass network connectivity improved by boron anomaly, which was identified by a nuclear magnetic resonance analysis. The Vickers microhardness of the glass product, with the addition of 15 wt.% B(2)O(3) and 15 wt.% Na(2)O, was about 4030 MPa. Furthermore, the changes in microstructure were consistent with those in the chemical stability by the toxicity characteristic leaching procedure (TCLP).

Study of Experiment on Rock-like Material Consist of fly-ash, Cement and Mortar

NASA Astrophysics Data System (ADS)

Nan, Qin; Hongwei, Wang; Yongyan, Wang

2018-03-01

Study the uniaxial compression test of rock-like material consist of coal ash, cement and mortar by changing the sand cement ratio, replace of fine coal, grain diameter, water-binder ratio and height-diameter ratio. We get the law of four factors above to rock-like material’s uniaxial compression characteristics and the quantitative relation. The effect law can be sum up as below: sample’s uniaxial compressive strength and elasticity modulus tend to decrease with the increase of sand cement ratio, replace of fine coal and water-binder ratio, and it satisfies with power function relation. With high ratio increases gradually, the uniaxial compressive strength and elastic modulus is lower, and presents the inverse function curve; Specimen tensile strength decreases gradually with the increase of fly ash. By contrast, uniaxial compression failure phenomenon is consistent with the real rock common failure pattern.

Evaluating the fate of metals in air pollution control residues from coal-fired power plants

EPA Science Inventory

Changes in air pollution control at coal-fired power plants are shifting mercury (Hg) and other metals from the flue gas at electric utilities to the coal ash. This paper presents data from the characterization of73 coal combustion residues (CCRs) evaluating the composition and c...

Impact of nongray multiphase radiation in pulverized coal combustion

NASA Astrophysics Data System (ADS)

Roy, Somesh; Wu, Bifen; Modest, Michael; Zhao, Xinyu

2016-11-01

Detailed modeling of radiation is important for accurate modeling of pulverized coal combustion. Because of high temperature and optical properties, radiative heat transfer from coal particles is often more dominant than convective heat transfer. In this work a multiphase photon Monte Carlo radiation solver is used to investigate and to quantify the effect of nongray radiation in a laboratory-scale pulverized coal flame. The nongray radiative properties of carrier phase (gas) is modeled using HITEMP database. Three major species - CO, CO2, and H2O - are treated as participating gases. Two optical models are used to evaluate radiative properties of coal particles: a formulation based on the large particle limit and a size-dependent correlation. Effect of scattering due to coal particle is also investigated using both isotropic scattering and anisotropic scattering using a Henyey-Greenstein function. Lastly, since the optical properties of ash is very different from that of coal, the effect of ash content on the radiative properties of coal particle is examined. This work used Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation Grant Number ACI-1053575.

Relationships between sedimentation, depositional environments, and coal quality: upper Potomac coalfield, West Virginia and Maryland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jake, T.R.

1987-09-01

Evaluations were made of sedimentation patterns and depositional environments from approximately 450 core logs and 225 surface exposures in the Upper Potomac coalfield. The relationships between the clastic depositional facies and the distribution and quality of the Bakerstown and upper Freeport coals were also investigated. Data from 61 Bakerstown and 35 upper Freeport coal samples from selected cores indicate a change from uniform coal quality to highly variable coal quality when moving from related interchannel and bay-fill facies to channel, channel-fill, levee, and crevasse-splay facies. Areas of uniform coal quality range from 20-26% ash and 55-62% fixed carbon (weight percent,more » dry basis), whereas areas of highly variable coal quality range from 26-54% ash and 33-55% fixed carbon. The channel and related facies represent areas where increased fresh water was introduced into the topogenous swamp system, causing increased microbial degradation and the concentration of authigenic minerals within the peat material. These conditions, combined with the introduction of detrital minerals, resulted in areas of lower quality coal.« less

Elemental analyses of chars isolated from a biomass gasifier fly ash

Treesearch

Thomas L. Eberhardt; Hui Pan

2012-01-01

Processing of pine wood chips in a pilot-scale downdraft gasifier generated a carbon-rich fly ash as a byproduct. Studies on biomass-derived fly ashes have generally focused on their direct characterisation, as generated, to develop options for utilisation or disposal. Analogous to studies on coal-derived fly ashes, strategies were applied here to assess the...

Leaching properties of stabilised/solidified cement-admixtures-sewage sludges systems.

PubMed

Valls, S; Vàzquez, E

2002-01-01

One of the main objectives of this work is to present an effective alternative for the final destination of sludge from urban waste water treatment plants by its use as a component of mortar or concrete. A binding and stabilizing matrix of sludge-cement and sludge-cement-coal fly-ash was investigated and the effects of various percentages of waste and binder, on the behavior of sludge in the system are presented. Assessment of the environmental quality of the final product and the consequent guarantee of its use in the building industry demand that it meets a number of requisites, one of which is that the effluents extracted by water action should be contamination-free, or at least that the concentration of contaminants should be below certain pre-set limits. For this a number of leaching tests must be carried out, such as the Netherlands Leaching Test .

Investigation on Leaching Behaviour of Fly Ash and Bottom Ash Replacement in Self-Compacting Concrete

NASA Astrophysics Data System (ADS)

Kadir, Aeslina Abdul; Ikhmal Haqeem Hassan, Mohd; Bakri Abdullah, Mohd Mustafa Al

2016-06-01

Fly ash and bottom ash are some of the waste generated by coal-fired power plants, which contains large quantities of toxic and heavy metals. In recent years, many researchers have been interested in studying on the properties of self-compacting concrete incorporated with fly ash and bottom ash but there was very limited research from the combination of fly ash and bottom ash towards the environmental needs. Therefore, this research was focused on investigating the leachability of heavy metals of SCC incorporated with fly ash and bottom ash by using Toxicity Characteristic Leaching Procedure, Synthetic Precipitation Leaching Procedure and Static Leaching Test. The samples obtained from the coal-fired power plant located at Peninsula, Malaysia. In this study, the potential heavy metals leached out from SCC that is produced with fly ash as a replacement for Ordinary Portland Cement and bottom ash as a substitute for sand with the ratios from 10% to 30% respectively were designated and cast. There are eight heavy metals of concern such as As, Cr, Pb, Zn, Cu, Ni, Mn and Fe. The results indicated that most of the heavy metals leached below the permissible limits from the United States Environmental Protection Agency and World Health Organization limit for drinking water. As a conclusion, the minimum leaching of the heavy metals from the incorporation of fly ash and bottom ash in self-compacting concrete was found in 20% of fly ash and 20% of bottom ash replacement. The results also indicate that this incorporation could minimize the potential of environmental problems.

Coal upgrading program for Usti nad Labem, Czech Republic: Task 8.3. Topical report, October 1994--August 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Young, B.C.; Musich, M.A.

1995-10-01

Coal has been a major energy source in the Czech Republic given its large coal reserves, especially brown coal and lignite (almost 4000 million metric tons) and smaller reserves of hard, mainly bituminous, coal (over 800 million tons). Political changes since 1989 have led to the reassessment of the role of coal in the future economy as increasing environmental regulations affect the use of the high-sulfur and high-ash brown coal and lignite as well as the high-ash hard coal. Already, the production of brown coal has declined from 87 million metric tons per year in 1989 to 67 million metricmore » tons in 1993 and is projected to decrease further to 50 million metric tons per year of brown coal by the year 2000. As a means of effectively utilizing its indigenous coal resources, the Czech Republic is upgrading various technologies, and these are available at different stages of development, demonstration, and commercialization. The purpose of this review is to provide a database of information on applicable technologies that reduce the impact of gaseous (SO{sub 2}, NO{sub x}, volatile organic compounds) and particulate emissions from the combustion of coal in district and residential heating systems.« less

Novel two stage bio-oxidation and chlorination process for high strength hazardous coal carbonization effluent.

PubMed

Manekar, Pravin; Biswas, Rima; Karthik, Manikavasagam; Nandy, Tapas

2011-05-15

Effluent generated from coal carbonization to coke was characterized with high organic content, phenols, ammonium nitrogen, and cyanides. A full scale effluent treatment plant (ETP) working on the principle of single stage carbon-nitrogen bio-oxidation process (SSCNBP) revealed competition between heterotrophic and autotrophic bacteria in the bio-degradation and nitrification process. The effluent was pretreated in a stripper and further combined with other streams to treat in the SSCNBP. Laboratory studies were carried on process and stripped effluents in a bench scale model of ammonia stripper and a two stage bio-oxidation process. The free ammonia removal efficiency of stripper was in the range 70-89%. Bench scale studies of the two stage bio-oxidation process achieved a carbon-nitrogen reduction at 6 days hydraulic retention time (HRT) operating in an extended aeration mode. This paper addresses the studies on selection of a treatment process for removal of organic matter, phenols, cyanide and ammonia nitrogen. The treatment scheme comprising ammonia stripping (pretreatment) followed by the two stage bio-oxidation and chlorination process met the Indian Standards for discharge into Inland Surface Waters. This treatment process package offers a techno-economically viable treatment scheme to neuter hazardous effluent generated from coal carbonization process. Copyright © 2011 Elsevier B.V. All rights reserved.

KINETIC STUDY OF ADSORPTION AND TRANSFORMATION OF MERCURY ON FLY ASH PARTICLES IN AN ENTRAINED FLOW REACTOR

EPA Science Inventory

Experimental studies were performed to investigate the interactions of elemental mercury vapor with entrained fly ash particles from coal combustion in a flow reactor. The rate of transformation of elemental mercury on fly ash particles was evauated over the temperature range fro...

Effect of pond ash on pen surface properties

USDA-ARS?s Scientific Manuscript database

Maintaining adequate feedlot pen surfaces is expensive. Pond ash (PA), a coal-fired electrical generation by-product, has good support qualities. A study was conducted comparing the performance of pond ash (PA) surfaced pens with soil surface (SS) pens. Four pens of an eight pen series with dimensio...

Leaching characteristics of solid wastes from thermal power plants of western Turkey and comparison of toxicity methodologies.

PubMed

Baba, Alper; Kaya, Abidin

2004-11-01

Use of lignite in power generation has led to increasing environmental problems associated not only with gaseous emissions, but also with the disposal of ash residues. In particular, use of low quality coals with high ash content results in huge quantities of both fly and bottom ashes to be disposed of. A main problem related to coal ash disposal is the heavy metal content of the residue. In this regard, experimental results of numerous studies indicate that toxic trace metals may leach when fly and bottom ashes are in contact with water. In this study, fly and bottom ash samples obtained from thermal power plants, namely Yenikoy, Kemerkoy and Yatagan, located at the southwestern coast of Turkey, were subjected to toxicity tests such as the extraction (EP) and toxicity characteristic leaching (TCLP) procedures of the US Environmental Protection Agency (USEPA) and the so-called 'Method A' extraction procedure of the American Society of Testing and Material (ASTM). The geochemical composition of ash samples showed variations depending on the coal burned in the plants. Furthermore, the EP, TCLP and ASTM toxicity tests showed variations such that the ash samples were classified as 'toxic waste' based on EP and TCLP results whereas they were classified as 'non-toxic' based on ASTM results, indicating test results are pH dependent. When the extraction results were compared with the chemical composition of water samples obtained in the vicinity of the thermal power plants, it was found that the results obtained using the ASTM procedure cannot be used to predict subsurface contamination whereas the EP and TCLP procedures can be used.

RARE EARTH ELEMENTS IN FLY ASHES AS POTENTIAL INDICATORS OF ANTHROPOGENIC SOIL CONTAMINATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mattigod, Shas V.

2003-08-01

Studies of rare earth element (REE) content of disposed fly ashes and their potential mobility were neglected for decades because these elements were believed to be environmentally benign. A number of recent studies have now shown that REE may pose a long-term risk to the biosphere. Therefore, there is a critical need to study the REE concentrations in fly ash and their potential mobilization and dispersal upon disposal in the environment. We analyzed the REE content of bulk, size fractionated, and density separated fractions of three fly ash samples derived from combustion of sub bituminous coals from the western Unitedmore » States and found that the concentrations of these elements in bulk ashes were within the range typical of fly ashes derived from coals from the North American continent. The concentrations of light rare earth elements (LREE) such as La, Ce, and Nd, however, tended towards the higher end of the concentration range whereas, the concentrations of middle rare earth elements (MREE) (Sm and Eu) and heavy rare earth elements (HREE) (Lu) were closer to the lower end of the observed range for North American fly ashes. The concentrations of REE did not show any significant enrichment with decreasing particle size, this is typical of nonvolatile lithophilic element behavior during the combustion process. The lithophilic nature of REE was also confirmed by their concentrations in heavy density fractions of these fly ashes being on average about two times more enriched than the concentrations in the light density fractions. Shale normalized average of REE concentrations of fly ashes and coals revealed significant positive anomalies for Eu and Dy. Because of these distinctive positive anomalies of Eu and Dy, we believe that fly ash contamination of soils can be fingerprinted and distinguished from other sources of anthropogenic REE inputs in to the environment.« less

Viscosity Determination of Molten Ash from Low-Grade US Coals

DOE PAGES

Zhu, Jingxi; Nakano, Jinichiro; Kaneko, Tetsuya Kenneth; ...

2012-10-01

In entrained slagging gasifiers, the fluidity of the molten ash is a critical factor for process control since it affects slag formation, the capture of inorganic constituents, refractory wear, and slag drainage along the gasification chamber walls. The use of western coal, or mixtures of eastern and western coals as gasifier feedstock, is likely to occur as western coals become available and technological issues that hinder their use are being resolved. In the present work, the viscosity of synthetic slags with ash chemistries simulating the western U.S. coals, was experimentally measured at a Po 2 = 10 - 8 atmmore » in the temperature range of 1773–1573 K (1500–1300 °C) using a rotating-bob viscometer. Alumina spindles and containment crucibles of both alumina and zirconia were used. Crystallization studies of this slag using a confocal scanning laser microscope found that a (Mg,Fe)Al 2O 4-based spinel precipitated at temperatures below 1723 K (1450 °C), and this agreed with FactSage equilibrium phase prediction. The same spinels were observed in the post-viscometry experiment slags when ZrO 2 crucibles were used and assumed to be in equilibrium with the slag at the higher temperatures. Zirconia dissolution resulted in a slight increase in the solid fraction present in slags at lower temperatures, compared to spinel fraction. Crystal precipitation changed the apparent activation energy and required a longer stabilization times for viscosity measurements. The viscosity results were used in predictive equations based on Veytsman and Einstein's models, with critical nucleation temperatures and the solid fraction calculated with FactSage. In the simulated eastern/western coal feedstock blends based on ash compositions, the fractions of the solid precipitates were also calculated using the thermodynamic program FactSage for each blend composition, and the plastic viscosity of each eastern/western coal slag blend was predicted using Veytsman's model and compared to available experimental data.« less

Partitioning of selected trace elements in coal combustion products from two coal-burning power plants in the United States

USGS Publications Warehouse

Swanson, Sharon M.; Engle, Mark A.; Ruppert, Leslie F.; Affolter, Ronald H.; Jones, Kevin B.

2013-01-01

Samples of feed coal (FC), bottom ash (BA), economizer fly ash (EFA), and fly ash (FA) were collected from power plants in the Central Appalachian basin and Colorado Plateau to determine the partitioning of As, Cr, Hg, Pb, and Se in coal combustion products (CCPs). The Appalachian plant burns a high-sulfur (about 3.9 wt.%) bituminous coal from the Upper Pennsylvanian Pittsburgh coal bed and operates with electrostatic precipitators (ESPs), with flue gas temperatures of about 163 °C in the ESPs. At this plant, As, Pb, Hg, and Se have the greatest median concentrations in FA samples, compared to BA and EFA. A mass balance (not including the FGD process) suggests that the following percentages of trace elements are captured in FA: As (48%), Cr (58%), Pb (54%), Se (20%), and Hg (2%). The relatively high temperatures of the flue gas in the ESPs and low amounts of unburned C in FA (0.5% loss-on-ignition for FA) may have led to the low amount of Hg captured in FA. The Colorado Plateau plant burns a blend of three low-S (about 0.74 wt.%) bituminous coals from the Upper Cretaceous Fruitland Formation and operates with fabric filters (FFs). Flue gas temperatures in the baghouses are about 104 °C. The elements As, Cr, Pb, Hg, and Se have the greatest median concentrations in the fine-grained fly ash product (FAP) produced by cyclone separators, compared to the other CCPs at this plant. The median concentration of Hg in FA (0.0983 ppm) at the Colorado Plateau plant is significantly higher than that for the Appalachian plant (0.0315 ppm); this higher concentration is related to the efficiency of FFs in Hg capture, the relatively low temperatures of flue gas in the baghouses (particularly in downstream compartments), and the amount of unburned C in FA (0.29% loss-on-ignition for FA).

STUDY OF RADON, THORON EXHALATION AND NATURAL RADIOACTIVITY IN COAL AND FLY ASH SAMPLES OF KOTA SUPER THERMAL POWER PLANT, RAJASTHAN, INDIA.

PubMed

Singh, Lalit Mohan; Kumar, Mukesh; Sahoo, B K; Sapra, B K; Kumar, Rajesh

2016-10-01

Electricity generation in India is largely dependent on coal-based thermal power plants, and increasing demand of energy raised the coal consumption in the power plants. In recent years, study of natural radioactivity content and radon/thoron exhalation from combustion of coal and its by-products has given considerable attention as they have been recognised as one of the important technically enhanced naturally occurring radioactive materials. In the present study, radon, thoron exhalation rate and the radioactivity concentration of radionuclides in coal and fly ash samples collected from Kota Super Thermal Power Plant, Rajasthan, India have been measured and compared with data of natural soil samples. The results have been analysed and discussed. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Chemical Imaging Analysis of Environmental Particles Using the Focused Ion Beam/Scanning Electron Microscopy Technique. Microanalysis Insights into Atmospheric Chemistry of Fly Ash

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Haihan; Grassian, Vicki H.; Saraf, Laxmikant V.

2012-11-08

Airborne fly ash from coal combustion may represent a source of bioavailable iron (Fe) in the open ocean. However, few studies have been made focusing on Fe speciation and distribution in coal fly ash. In this study, chemical imaging of fly ash has been performed using a dual-beam FIB/SEM (focused ion beam/scanning electron microscope) system for a better understanding of how simulated atmospheric processing modify the morphology, chemical compositions and element distributions of individual particles. A novel approach has been applied for cross-sectioning of fly ash specimen with a FIB in order to explore element distribution within the interior ofmore » individual particles. Our results indicate that simulated atmospheric processing causes disintegration of aluminosilicate glass, a dominant material in fly ash particles. Aluminosilicate-phase Fe in the inner core of fly ash particles is more easily mobilized compared with oxide-phase Fe present as surface aggregates on fly ash spheres. Fe release behavior depends strongly on Fe speciation in aerosol particles. The approach for preparation of cross-sectioned specimen described here opens new opportunities for particle microanalysis, particular with respect to inorganic refractive materials like fly ash and mineral dust.« less

49 CFR 387.301 - Surety bond, certificate of insurance, or other securities.

Code of Federal Regulations, 2010 CFR

2010-10-01

... in bulk. Cement, building blocks. Charcoal. Chemical fertilizer. Cinder blocks. Cinders, coal. Coal. Coke. Commercial fertilizer. Concrete materials and added mixtures. Corn cobs. Cottonseed hulls... nitrate of soda. Anhydrous ammonia—used as a fertilizer only. Ashes, wood or coal. Bituminous concrete...

[Predicting low NOx combustion property of a coal-fired boiler].

PubMed

Zhou, Hao; Mao, Jianbo; Chi, Zuohe; Jiang, Xiao; Wang, Zhenhua; Cen, Kefa

2002-03-01

More attention was paid to the low NOx combustion property of the high capacity tangential firing boiler, but the NOx emission and unburned carbon content in fly ash of coal burned boiler were complicated, they were affected by many factors, such as coal character, boiler's load, air distribution, boiler style, burner style, furnace temperature, excess air ratio, pulverized coal fineness and the uniformity of the air and coal distribution, etc. In this paper, the NOx emission property and unburned carbon content in fly ash of a 600 MW utility tangentially firing coal burned boiler was experimentally investigated, and taking advantage of the nonlinear dynamics characteristics and self-learning characteristics of artificial neural network, an artificial neural network model on low NOx combustion property of the high capacity boiler was developed and verified. The results illustrated that such a model can predicate the NOx emission concentration and unburned carbon content under various operating conditions, if combined with the optimization algorithm, the operator can find the best operation condition of the low NOx combustion.

Co-combustion of anthracite coal and wood pellets: Thermodynamic analysis, combustion efficiency, pollutant emissions and ash slagging.

PubMed

Guo, Feihong; Zhong, Zhaoping

2018-08-01

This work presents studies on the co-combustion of anthracite coal and wood pellets in fluidized bed. Prior to the fluidized bed combustion, thermogravimetric analysis are performed to investigate the thermodynamic behavior of coal and wood pellets. The results show that the thermal decomposition of blends is divided into four stages. The co-firing of coal and wood pellets can promote the combustion reaction and reduce the emission of gaseous pollutants, such as SO 2 and NO. It is important to choose the proportion of wood pellets during co-combustion due to the low combustion efficiency caused by large pellets with poor fluidization. Wood pellets can inhibit the volatilization of trace elements, especially for Cr, Ni and V. In addition, the slagging ratio of wood pellets ash is reduced by co-firing with coal. The research on combustion of coal and wood pellets is of great significance in engineering. Copyright © 2018 Elsevier Ltd. All rights reserved.

REDUCING POWER PRODUCTION COSTS BY UTILIZING PETROLEUM COKE

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1998-09-01

A Powder River Basin subbituminous coal from the North Antelope mine and a petroleum shot coke were received from Northern States Power Company (NSP) for testing the effects of parent fuel properties on coal-coke blend grindability and evaluating the utility of petroleum coke blending as a strategy for improving electrostatic precipitator (ESP) particulate collection efficiency. Petroleum cokes are generally harder than coals, as indicated by Hardgrove grindability tests. Therefore, the weaker coal component may concentrate in the finer size fractions during the pulverizing of coal-coke blends. The possibility of a coal-coke size fractionation effect is being investigated because it maymore » adversely affect combustion performance. Although the blending of petroleum coke with coal may adversely affect combustion performance, it may enhance ESP particulate collection efficiency. Petroleum cokes contain much higher concentrations of V relative to coals. Consequently, coke blending can significantly increase the V content of fly ash resulting from coal-coke combustion. Pentavalent vanadium oxide (V{sub 2}O{sub 5}) is a known catalyst for transforming gaseous sulfur dioxide (SO{sub 2}[g]) to gaseous sulfur trioxide (SO{sub 3}[g]). The presence of SO{sub 3}(g) strongly affects fly ash resistivity and, thus, ESP performance.« less

An in situ occurrence of coal balls in the Amburgy coal bed, Pikeville Formation (Duckmantian), central Appalachian Basin, USA

USGS Publications Warehouse

Greb, S.F.; Eble, C.F.; Chesnut, D.R.; Phillips, T.L.; Hower, J.C.

1999-01-01

Carbonate concretions containing permineralized peat, commonly called coal balls, were encountered in the Amburgy coal, a generally low-ash (9.4%), but commonly high-sulfur (3.6%), Middle Pennsylvanian coal of the Eastern Kentucky Coal Field. These are the first coal balls from the Amburgy coal, and one of only a few reported occurrences from the central Appalachian Basin. The coal balls occur in the upper part of the coal, between two paleochannel cut-outs at the top of the Pikeville Formation, and immediately beneath a scour with a marine fossil lag at the base of the Kendrick Shale Member, Hyden Formation. The coal is thickest (1.3 m) in a narrow (<300 m), elongate depression between the bounding paleochannels, and thins toward the occurrence of coal balls. Total biovolume as measured from acetate peels of coal balls indicates cordaites or lycopsid (36.1% each) dominance. Vertical sampling through one coal-ball aggregate shows zoning from a lower cordaites-dominant (88.7%) assemblage, to a middle, degraded, sphenopsid-rich assemblage, to an upper lycopsid-dominant (88.6%) assemblage. Beneath the coal balls, palynologic and petrographic analyses indicate the basal and middle portions of the bed are dominated by arborescent lycopsid spores and cordaites pollen, and by vitrinite macerals. The top part of the bed, above the coal balls, contains increased intertinite macerals, increased percentages of small fern spores, and variable ash yield (5-21%). Thickening of the Amburgy coal along a structural low, in combination with basal high-ash yields, vitrinite-dominance, and heterogenous palynoflora, indicate paleotopographic control on initial peat accumulation. Abundant lycopsid spores in the basal and middle part of the coal reflect rheotrophic conditions consistent with accumulation in a paleotopographic depression. Apparent zonation preserved in one of the coal-ball masses may document plant successions in response to flooding. Similar percentages of cordaites and lycopods, respectively, in the zones above and below the degraded incursion interval reflect development of a mixed, successional pattern in response to the flooding. Coal-ball formation may have been facilitated by channeling along the Kendrick ravinement, within a paleotopographic depression, at the split margin of the Amburgy peat, either through direct transmittal of carbonates and marine waters into the peat, or through degassing of the peat beneath the scour.

Toxic airborne S, PAH, and trace element legacy of the superhigh-organic-sulphur Raša coal combustion: Cytotoxicity and genotoxicity assessment of soil and ash.

PubMed

Medunić, Gordana; Ahel, Marijan; Mihalić, Iva Božičević; Srček, Višnja Gaurina; Kopjar, Nevenka; Fiket, Željka; Bituh, Tomislav; Mikac, Iva

2016-10-01

This paper presents the levels of sulphur, polycyclic aromatic hydrocarbons (PAHs), and potentially toxic trace elements in soils surrounding the Plomin coal-fired power plant (Croatia). It used domestic superhigh-organic-sulphur Raša coal from 1970 until 2000. Raša coal was characterised by exceptionally high values of S, up to 14%, making the downwind southwest (SW) area surrounding the power plant a significant hotspot. The analytical results show that the SW soil locations are severely polluted with S (up to 4%), and PAHs (up to 13,535ng/g), while moderately with Se (up to 6.8mg/kg), and Cd (up to 4.7mg/kg). The composition and distribution pattern of PAHs in the polluted soils indicate that their main source could be airborne unburnt coal particles. The atmospheric dispersion processes of SO2 and ash particles have influenced the composition and distribution patterns of sulphur and potentially toxic trace elements in studied soils, respectively. A possible adverse impact of analysed soil on the local karstic environment was evaluated by cytotoxic and genotoxic methods. The cytotoxicity effects of soil and ash water extracts on the channel catfish ovary (CCO) cell line were found to be statistically significant in the case of the most polluted soil and ash samples. However, the primary DNA-damaging potential of the most polluted soil samples on the CCO cells was found to be within acceptable boundaries. Copyright © 2016 Elsevier B.V. All rights reserved.

Raccoons (Procyon lotor) as Sentinels of Trace Element Contamination and Physiological Effects of Exposure to Coal Fly Ash

DOE PAGES

Hernandez, Felipe; Oldenkamp, Ricki E.; Webster, Sarah; ...

2016-12-08

Anthropogenic pollutants disrupt global biodiversity, and terrestrial sentinels of pollution can provide a warning system for ecosystem-wide contamination. This study sought to assess whether raccoons (Procyon lotor) are sentinels of local exposure to trace element contaminants at a coal fly ash site and whether exposure resulted in health impairment or changes in the intestinal helminth communities. We compared trace element accumulation and the impact on health responses and intestinal helminth communities of raccoons inhabiting contaminated and reference sites of the U.S. Department of Energy’s Savannah River Site (South Carolina, USA). Data on morphometry, hematology, histopathology, helminth community and abundance, andmore » liver trace element burdens were collected from 15 raccoons captured adjacent to a coal fly ash basin and 11 raccoons from a comparable uncontaminated site nearby. Of eight trace elements analyzed, Cu, As, Se, and Pb were elevated in raccoons from the contaminated site. Raccoons from the contaminated site harbored higher helminth abundance than animals from the reference site and that abundance was positively associated with increased Cu concentrations. While we found changes in hematology associated with increased Se exposure, we did not find physiological or histological changes associated with higher levels of contaminants. Our results suggest that raccoons and their intestinal helminths act as sentinels of trace elements in the environment associated with coal fly ash contamination.« less

Raccoons (Procyon lotor) as Sentinels of Trace Element Contamination and Physiological Effects of Exposure to Coal Fly Ash

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hernandez, Felipe; Oldenkamp, Ricki E.; Webster, Sarah

Anthropogenic pollutants disrupt global biodiversity, and terrestrial sentinels of pollution can provide a warning system for ecosystem-wide contamination. This study sought to assess whether raccoons (Procyon lotor) are sentinels of local exposure to trace element contaminants at a coal fly ash site and whether exposure resulted in health impairment or changes in the intestinal helminth communities. We compared trace element accumulation and the impact on health responses and intestinal helminth communities of raccoons inhabiting contaminated and reference sites of the U.S. Department of Energy’s Savannah River Site (South Carolina, USA). Data on morphometry, hematology, histopathology, helminth community and abundance, andmore » liver trace element burdens were collected from 15 raccoons captured adjacent to a coal fly ash basin and 11 raccoons from a comparable uncontaminated site nearby. Of eight trace elements analyzed, Cu, As, Se, and Pb were elevated in raccoons from the contaminated site. Raccoons from the contaminated site harbored higher helminth abundance than animals from the reference site and that abundance was positively associated with increased Cu concentrations. While we found changes in hematology associated with increased Se exposure, we did not find physiological or histological changes associated with higher levels of contaminants. Our results suggest that raccoons and their intestinal helminths act as sentinels of trace elements in the environment associated with coal fly ash contamination.« less

Apparatus for mixing char-ash into coal stream

DOEpatents

Blaskowski, Henry J.

1982-03-16

Apparatus for obtaining complete mixing of char with coal prior to the introduction of the mixture into the combustor (30) of a coal gasifier (10). The coal is carried in one air stream (22), and the char in another air stream (54), to a riffle plate arrangement (26), where the streams of solid are intimately mixed or blended.

Comparison of coal/solid recovered fuel (SRF) with coal/refuse derived fuel (RDF) in a fluidised bed reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wagland, S.T.; Kilgallon, P.; Coveney, R.

2011-06-15

An experimental study was undertaken to compare the differences between municipal solid waste (MSW) derived solid recovered fuel (SRF) (complying with CEN standards) and refuse derived fuel (RDF). Both fuels were co-combusted with coal in a 50 kW fluidised bed combustor and the metal emissions were compared. Synthetic SRF was prepared in the laboratory by grinding major constituents of MSW such as paper, plastic, textile and wood. RDF was obtained from a local mechanical treatment plant. Heavy metal emissions in flue gas and ash samples from the (coal + 10% SRF) fuel mixture were found to be within the acceptablemore » range and were generally lower than that obtained for coal + 10% RDF fuel mixture. The relative distribution of heavy metals in ash components and the flue gas stream shows the presence of a large fraction (up to 98%) of most of the metals in the ash (except Hg and As). Thermo-gravimetric (TG) analysis of SRF constituents was performed to understand the behaviour of fuel mixtures in the absence and presence of air. The results obtained from the experimental study will enhance the confidence of fuel users towards using MSW-derived SRF as an alternative fuel.« less

Inorganic chemistry, petrography and palaeobotany of Permian coals in the Prince Charles Mountains, East Antarctica

USGS Publications Warehouse

Holdgate, G.R.; McLoughlin, S.; Drinnan, A.N.; Finkelman, R.B.; Willett, J.C.; Chiehowsky, L.A.

2005-01-01

Sampled outcrops of Permian coal seams of the Bainmedart Coal Measures in the Lambert Graben, eastern Antarctica, have been analysed for their proximates, ultimates, ash constituents and trace elements. A similar series of samples has been analysed for their principle maceral and microlithotype components and vitrinite reflectance. The coals are sub-bituminous to high volatile bituminous in rank; maturity increases markedly in southern exposures around Radok Lake where the oldest part of the succession is exposed and some strata have been intruded by mafic dykes and ultramafic sills. The coal ash is mostly silica and aluminium oxides, indicating that the mineral ash component is mostly quartz and various clay minerals. The ratio of silica to aluminium oxides appears to increase in an upward stratigraphic direction. The coal macerals include a relatively high liptinite content (mainly sporinite) that is significantly higher than for typical Gondwana coals. Greater degrees of weathering within the floodbasin/peat mire environments associated with climatic drying towards the end of the Permian might account for both preferential sporopollenin preservation and increased silica:aluminium oxide ratios up-section. Correlation of the coal maceral components to adjacent peninsula India coals indicates the closest comparative coals of similar age and rank occur within the Godavari Basin, rather then the Mahanadi Basin, which is traditionally interpreted to have been contiguous with the Lambert Graben before Gondwanan breakup. The petrological characteristics suggest that either previous interpretations of Palaeozoic basin alignments between Antarctica and India are incorrect, or that environmental settings and post-Permian burial histories of these basins were strongly independent of their tectonic juxtaposition. A permineralized peat bed within the succession reveals that the coals predominantly comprise wood- and leaf-rich debris derived from low-diversity forest-mire communities dominated by glossopterid and noeggerathiopsid gymnosperms. ?? 2005 Elsevier B.V. All rights reserved.

Economical and Environmentally Benign Extraction of Rare Earth Elements (REES) from Coal & Coal Byproducts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carlson, Gary

This final report provides a complete summary of the activities, results, analytical discussion, and overall evaluation of the project titled “Economical and Environmentally Benign Extraction of Rare Earth Elements (REES) from Coal & Coal Byproducts” under DOE Award Number DE-FE-0027155 that started in March 2016 and ended December 2017. Fly ash was selected as the coal-byproduct source material due to fact that it is readily available with no need for extensive methods to obtain the material, it is produced in large quantities (>50 million tons per year) and had REE concentrations similar to other coal-byproducts. The selected fly ash usedmore » throughout this project was from the Mill Creek power generating facility operated by Louisville Gas and Electric located in Louisville, KY and was subjected to a variety of physical and chemical characterization tests. Results from fusion extractions showed that the selected fly-ash had a TREE+Y concentration of 480 ppm with critical REEs concentration of 200 ppm. The fly ash had an outlook ratio of 1.25 and an estimated value of $16-$18 worth of salable REEs per 1-tonne of fly ash. Additional characterizations by optical evaluation, QEMSCAN, XRD, size fractionation, and SEM analysis showed the fly ash consisted of small glassy spherules with a size range between 1 to 110 µm (ave. diam. of 13 um), was heterogeneous in chemical composition (main crystalline phases: aluminum oxides and iron oxides) and was primarily an amorphous material (75 to 80%). A simple stepped approach was completed to estimate the total REE resource quantity. The approach included REE characterization of the representative samples, evaluation of fly-ash availability, and final determination estimated resource availability with regards to REE grade on a regional and national scale. This data represents the best available information and is based upon the assumptions that the power generating facility where the fly-ash was obtained will use the same coal sources (actual mines were identified), the coal materials will have relatively consistent REE concentrations, and the REE extraction process developed during this project can achieve 42% REE recovery (validated and confirmed). Calculations indicated that the estimated REE resource is approximately 175,000 tonnes with a current estimated value of $3,330MM. The proposed REE extraction and production process developed during this project used four fundamental steps; 1) fly-ash pretreatment to enhance REE extraction, 2) REE extraction by acid digestion, 3) REE separation/concentration by carbon adsorption and column chromatography, and 4) REE oxide production. Secondary processing steps to manage process residuals and additional processing techniques to produce value-added products were incorporated into the process during the project. These secondary steps were not only necessary to manage residuals, but also provided additional revenue streams that offset operational and capital expenditures. The process produces one value product stream (production of zeolite Na-P1), a solids waste stream, and one liquid stream that met RCRA discharge requirements. Based upon final design criteria and operational parameters, the proposed system could produce approximately 200 grams of REOs from 1-tonne of fly-ash, thereby representing a TREE+Y recovery of 42% (project target of > 25%). A detailed economic model was developed to evaluate both CAPEX and OPEX estimates for systems with varying capacities between 100 kg to 200 tonnes of fly ash processed per day. Using a standard system capacity of 10 tonne/day system, capital costs were estimated at $88/kg fly ash while operating costs were estimated at approximately $450/kg fly ash. This operating cost estimate includes a revenue of $495/tonne of fly ash processed from the value-added product produced from the system (zeolite Na-P1). Although operating cost savings due to zeolite production were significant, the capital + operating cost for a 10 tonne system was more expensive than the total dollar value of REEs present in the fly ash material. Specifically, the estimated cost per 1-tonne of fly ash treated is approximately $540 while the estimated value of REEs in the fly ash is $18-$20/tonne. This is an excessive difference showing that the proposed process is not economically feasible strictly on the basis of REE revenue compared to extraction costs. Although the current proposed system does not produce sufficient quantities of REEs or additional revenue sources to offset operational and capital costs, supplementary factors including US strategic concerns, commercial demands, and defense department requirements must be factored. At this time, the process developed during this project provides foundational information for future development of simple processes that require low capital investment and one that will extract a valuable quality and quantity of REE oxides from industrial waste.« less

Assessment of compost application to coal ash disposal sites to promote the rapid vegetation establishment

NASA Astrophysics Data System (ADS)

Repmann, F.; Slazak, A.; Babic, M.; Schneider, B. U.; Schaaf, W.; Hüttl, R. F.

2009-04-01

In the city of Tuzla, located in Bosnia and Herzegovina, a coal fired thermo electric power plant is operated by the company JP ELEKTROPRIVERDA BIH TERMOELEKTRANA "TUZLA". High amounts of ash are produced by the power plant, which are currently disposed into settlement ponds bordered by dams in natural valleys. A total of four ash disposal sites covering an area of approx. 170 ha have been established during the last decades. Due to the fact that residual ash from coal combustion was found to contain a variety of trace elements (Ni, Cr, As, B), it must be assumed that ash disposal of that magnitude constitutes an environmental problem which is investigated within the EU-FP6 / STREP project "Reintegration of Coal Ash Disposal Sites and Mitigation of Pollution in the West Balkan Area" RECOAL. The main hazards relate to soil and groundwater contamination due to leaching toxins, dust dispersion, and toxins entering the food chain as these disposal sites are used for agricultural purposes. In order to rapidly establish a vegetation cover on barren ash dumps that particularly would prevent dust erosion we assessed the applicability of compost, produced from locally available municipal and industrial organic residues as an amendment to ash to improve substrate fertility. The envisaged remediation technology was considered to be a low cost, easy applicable and rapid method capable of substantially enhancing living conditions of residents in the vicinity of the abandoned disposal sites. Various compost application rates were evaluated in the field on experimental site Divkovici I in Tuzla and additionally in the greenhouse environment at Brandenburg Technical University Cottbus. Field and laboratory tests revealed that plant growth and cover rate can substantially be improved by mixing compost into the upper ash layer to a maximum depth of approx. 20 cm. Besides direct growth observations in the field analysis of soil parameters gave evidence that the fertility of ashy substrates amended with compost produced from locally available sewage sludge and saw dust can be improved. The metal content of grass grown in the various treatments was considered to be elevated compared to normal contents. However, metal uptake in compost treatments was lower than in untreated plots. A preliminary cost assessment, comparing the remediation technology tested on site Divkovici with a standard soil covering technique revealed financial benefits for the compost method due to significant lower application rates.

FUNDAMENTALS OF MERCURY SPECIATION AND CONTROL IN COAL-FIRED BOILERS

EPA Science Inventory

The report describes the progress of an experimental investigation of the speciation of mercury in simulated coal combustion flue gasses. The effects of flue gas parameters and coal fly ash on the oxidation of elemental mercury (Hgo) in the presence of hydrogen chloride (HCl) in ...

Comparing soil and pond ash feedlot pen surfaces for environmental management

USDA-ARS?s Scientific Manuscript database

Removing manure and replacing soil to maintain pen surfaces is expensive. Pond ash (PA), a coal-fired electrical generation by-product, has good support qualities. A study was conducted comparing the performance of pond ash (PA) surfaced pens with soil surface (SS) pens. Four pens of an eight pen se...

Design and evaluation of high-volume fly ash (HVFA) concrete mixes, report E : hardened mechanical properties and durability performance of HVFA concrete.

DOT National Transportation Integrated Search

2012-10-01

A rising concern in todays construction industry is environmental responsibility. : The addition of fly ash is a leading innovation in sustainable design of concrete. Fly ash, : a waste by-product of coal burning power plants, can be used to repla...

Theoretical Investigation of the Process of Steam-Oxygen Gasification of Coke-Ash Particles in a Fluidized Bed Under Pressure

NASA Astrophysics Data System (ADS)

Rokhman, B. B.

2015-03-01

The problem on the evolution of the state of an ensemble of reacting coke-ash particles in a fluidized-bed gas generator is considered. A kinetic equation for the distribution function of particles within small ranges of carbon concentration variation for the stages of surface and bulk reaction has been constructed and integrated. Boundary conditions ("matching" conditions) at the boundaries between these ranges are formulated. The influence of the granulometric composition of the starting coal, height, porosity, and of the bed temperature on the process of steam-oxygen gasification of coke-ash particles of individual sorts of fuel and of a binary coal mixture has been investigated.

Petrology and palynology of the No. 5 block coal bed, northeastern Kentucky

USGS Publications Warehouse

Hower, J.C.; Eble, C.F.; Rathbone, R.F.

1994-01-01

The upper Middle Pennsylvanian (middle Westphalian D equivalent) No. 5 Block coal bed (Eastern Kentucky Coal Field of the Central Appalachian Basin) is a low-sulfur, compliance coal resource, dominantly comprised of dull, inertinite-rich lithotypes. Ash yields tend to be highly variable in the No. 5 Block, as does bed thickness and frequency of bed splitting. This study describes the petrographic, palynologic and geochemical characteristics of the No. 5 Block coal bed, and reports on some temporal and spatial trends among these parameters in eastern-northeastern Kentucky. Petrographically the No. 5 Block coal is predominated by dull, often high-ash lithotypes, with inertinite contents commonly exceeding 30% (mmf). The coal thins to the north-northwest where it tends to be higher in vitrinite and sulfur content. Representatives of large and small lycopsids and ferns (both tree-like and small varieties) dominate the No. 5 Block coal bed palynoflora. Calamite spores and cordaite pollen also occur but are less abundant. Small lycopsid (Densosporites spp. and related crassicingulate genera) and tree fern (e.g. Punctatisporites minutus, Laevigatosporites globosus) spore taxa are most abundant in dull lithotypes. Bright lithotypes contain higher percentages of arboreous lycopsid spores (Lycospora spp.). Regionally, the No. 5 Block coal contains abundant Torispora securis, a tree fern spore specially adapted for desiccation prevention. This, along with overall high percentages of inertinite macerals, suggest that peat accumulation may have taken place in a seasonally dry (?) paleoclimate. The No. 5 Block coal bed thickens rather dramatically in a NW-SE direction, as does the frequency of coal bed splitting. This phenomenon appears to be related to increased accomodation space in the southeastern portion of the study area, perhaps via penecontemporaneous growth faulting. Maceral and palynomorph variations within the bed correspond with these changes. Thin coal along the northwestern margin tends to be vetrinite rich and contains abundant Lycospora, perhaps reflecting relatively stable peat-forming conditions. Thicker coal to the southeast contains more inertinite, high-ash coal layers, and inorganic partings. Spore floras contain more small lycopsid and tree fern components and are temporally variable, perhaps indicating a more unstable peat-forming environment. ?? 1994.

Characterization of Transient Receptor Potential Vanilloid-1 (TRPV1) Variant Activation by Coal Fly Ash Particles and Associations with Altered Transient Receptor Potential Ankyrin-1 (TRPA1) Expression and Asthma*

PubMed Central

Stockmann, Chris; Romero, Erin G.; Lu, Zhenyu; Shapiro, Darien; Stone, Bryan L.; Fassl, Bernhard; Nkoy, Flory; Uchida, Derek A.; Ward, Robert M.; Veranth, John M.; Reilly, Christopher A.

2016-01-01

Transient receptor potential (TRP) channels are activated by environmental particulate materials. We hypothesized that polymorphic variants of transient receptor potential vanilloid-1 (TRPV1) would be uniquely responsive to insoluble coal fly ash compared with the prototypical soluble agonist capsaicin. Furthermore, these changes would manifest as differences in lung cell responses to these agonists and perhaps correlate with changes in asthma symptom control. The TRPV1-I315M and -T469I variants were more responsive to capsaicin and coal fly ash. The I585V variant was less responsive to coal fly ash particles due to reduced translation of protein and an apparent role for Ile-585 in activation by particles. In HEK-293 cells, I585V had an inhibitory effect on wild-type TRPV1 expression, activation, and internalization/agonist-induced desensitization. In normal human bronchial epithelial cells, IL-8 secretion in response to coal fly ash treatment was reduced for cells heterozygous for TRPV1-I585V. Finally, both the I315M and I585V variants were associated with worse asthma symptom control with the effects of I315M manifesting in mild asthma and those of the I585V variant manifesting in severe, steroid-insensitive individuals. This effect may be due in part to increased transient receptor potential ankyrin-1 (TRPA1) expression by lung epithelial cells expressing the TRPV1-I585V variant. These findings suggest that specific molecular interactions control TRPV1 activation by particles, differential activation, and desensitization of TRPV1 by particles and/or other agonists, and cellular changes in the expression of TRPA1 as a result of I585V expression could contribute to variations in asthma symptom control. PMID:27758864

Characterization of Transient Receptor Potential Vanilloid-1 (TRPV1) Variant Activation by Coal Fly Ash Particles and Associations with Altered Transient Receptor Potential Ankyrin-1 (TRPA1) Expression and Asthma.

PubMed

Deering-Rice, Cassandra E; Stockmann, Chris; Romero, Erin G; Lu, Zhenyu; Shapiro, Darien; Stone, Bryan L; Fassl, Bernhard; Nkoy, Flory; Uchida, Derek A; Ward, Robert M; Veranth, John M; Reilly, Christopher A

2016-11-25

Transient receptor potential (TRP) channels are activated by environmental particulate materials. We hypothesized that polymorphic variants of transient receptor potential vanilloid-1 (TRPV1) would be uniquely responsive to insoluble coal fly ash compared with the prototypical soluble agonist capsaicin. Furthermore, these changes would manifest as differences in lung cell responses to these agonists and perhaps correlate with changes in asthma symptom control. The TRPV1-I315M and -T469I variants were more responsive to capsaicin and coal fly ash. The I585V variant was less responsive to coal fly ash particles due to reduced translation of protein and an apparent role for Ile-585 in activation by particles. In HEK-293 cells, I585V had an inhibitory effect on wild-type TRPV1 expression, activation, and internalization/agonist-induced desensitization. In normal human bronchial epithelial cells, IL-8 secretion in response to coal fly ash treatment was reduced for cells heterozygous for TRPV1-I585V. Finally, both the I315M and I585V variants were associated with worse asthma symptom control with the effects of I315M manifesting in mild asthma and those of the I585V variant manifesting in severe, steroid-insensitive individuals. This effect may be due in part to increased transient receptor potential ankyrin-1 (TRPA1) expression by lung epithelial cells expressing the TRPV1-I585V variant. These findings suggest that specific molecular interactions control TRPV1 activation by particles, differential activation, and desensitization of TRPV1 by particles and/or other agonists, and cellular changes in the expression of TRPA1 as a result of I585V expression could contribute to variations in asthma symptom control. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

The Eocene Thermal Maximum 2 (ETM-2) in a terrestrial section of the High Arctic: identification by U-Pb zircon ages of volcanic ashes and carbon isotope records of coal and amber (Stenkul Fiord, Ellesmere Island, Canada)

NASA Astrophysics Data System (ADS)

Reinhardt, Lutz; von Gosen, Werner; Piepjohn, Karsten; Lückge, Andreas; Schmitz, Mark

2017-04-01

The Stenkul Fiord section on southern Ellesmere Island reveals largely fluvial clastic sediments with intercalated coal seams of the Margaret Formation of Late Paleocene/Early Eocene age according to palynology and vertebrate remains. Field studies in recent years and interpretative mapping of a high-resolution satellite image of the area southeast of Stenkul Fiord revealed that the clastic deposits consist of at least four sedimentary units (Units 1 to 4) separated by unconformities. Several centimeter-thin volcanic ash layers, recognized within coal layers and preserved as crandallite group minerals (Ca-bearing goyazite), suggest an intense volcanic ash fall activity. Based on new U-Pb zircon ages (ID-TIMS) of three ash layers, the volcanic ash fall took place at 53.7 Ma in the Early Eocene, i.e. within the Eocene Thermal Maximum 2 (ETM-2) hyperthermal. The ETM-2 is bracketed further by discrete negative excursions of carbon isotope records of both bulk coal and amber droplets collected from individual coal layers of the section. The identification of the ETM-2 hyperthermal provides a stratigraphic tie-point in the terrestrial Margaret Formation sediments enabling assignment of the lowermost sedimentary Unit 1 to the Late Paleocene-earliest Eocene, Unit 2 to the Early Eocene, whereas Unit 3 and 4 might be Early to Middle Eocene in age. Thus the timing of syn-sedimentary movements of the Eurekan deformation causal for the observed unconformities in the section can be studied and the positions of further hyperthermals like the PETM or the ETM-3 in the section can be identified in the future. The integration of structural studies, new U-Pb zircon ages, and different carbon isotope records provides a new stratigraphic framework for further examination of the unique Early Eocene flora and fauna preserved in this high-latitude outcrop.

Accumulation and depuration of trace metals in Southern Toads, Bufo Terrestris, exposed to coal combustion waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ward, C.; Hassan, S.; Mendonca, M.

2009-02-15

Accumulation and depuration of metals by an organism are underrepresented in the literature. We collected southern toads (Bufo terrestris) from coal by-product (ash)-contaminated and uncontaminated sites to examine metal concentrations over time. Toads were placed in four exposure regimes, then sacrificed periodically over a 5-month period, and whole-body metal levels were measured. Toads exposed to ash accumulated significant concentrations of metals. Metal concentrations changed throughout the experiment, and profiles of accumulation and depuration differed depending on the metal and exposure regime. Ash-exposed toads exhibited elevated levels of 11 of 18 metals measured. Increases ranged from 47.5% for Pb to moremore » than 5000% for As. Eight of 18 metals did not change in control toads, while 10 of 18 metals decreased in toads removed from ash, ranging from -25% for Co to -96% for Tl. Seven metals that decreased in toads removed from ash did not change in control toads.« less

Development of clean coal and clean soil technologies using advanced agglomeration technologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ignasiak, B.; Pawlak, W.; Szymocha, K.

1990-04-01

The specific objectives of the bituminous coal program were to explore and evaluate the application of advanced agglomeration technology for: (1)desulphurization of bituminous coals to sulphur content acceptable within the current EPA SO{sub 2} emission guidelines; (2) deashing of bituminous coals to ash content of less than 10 percent; and (3)increasing the calorific value of bituminous coals to above 13,000 Btu/lb. (VC)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kochin, I.V.; Belichenko, A.G.; Livshits, B.Ya.

Modern mechanical methods of coal processing involve crushing and the emission of coal dust in substantial amounts into the shop atmosphere, along with noise and vibration problems. Wet cleaning processes produce high humidity, while flotation involves the use of toxic reagents (alcohols, oils, kerosene). The air in flotation shops reaches humidities of 91 to 95% at 20.1 to 24.3/sup 0/C and contains 1.6 to 28.2 mg/m/sup 3/ of coal dust (with 1.4 to 7.9% SiO/sub 2/) and up to 600 mg/m/sup 3/ of kerosene vapors. The introduction of process improvements, automation, and mechanization brings about a correlated reduction in absenteeismmore » through illness. Automation in the flotation section has improved both technical and economic performance; the labor productivity index has risen by 40% and the ash of the tailings has increased by 10%, while the phenols content of the shop effluent and the concentration of kerosene vapors in the shop have decreased by factors of 6.5 and 3 respectively. The working conditions have been correspondingly improved. It is worthwhile and necessary to extend and improve the work of the medical-engineering team. This represents a novel form of collaboration between the medical services and the plant staff, to overcome health problems, control health and safety hazards and improve the health of the labor force. Reductions in man-hour losses from illness provide a major source of increased working time and labor productivity.« less

Comparison of the petrography, palynology, and paleobotany of the Little Fire Creek coal bed, southwestern Virginia, USA

USGS Publications Warehouse

Pierce, B.S.; Eble, C.F.; Stanton, R.W.

1995-01-01

The proximate, petrographic, palynologic, and plant tissue data from two sets of samples indicate a high ash, gelocollinite- and liptinite-rich coal consisting of a relatively diverse paleoflora, including lycopsid trees, small lycopsids, tree ferns, small ferns, pteridosperms, and rare calamites and cordaites. The relatively very high ash yields the relatively thin subunits and the large scale vertical variations in palynomorph floras suggest that the study area was at the edge of the paleopeat-forming environment. -from Authors

Philadelphia gas works medium-Btu coal gasification project: environmental assessment. [GKT supplied by Krupp-Koppers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1981-12-01

The coal gasification plant will occupy a 43-acre site, known as the Riverside Site, located along the Delaware River next to Port Richmond between the Betsy Ross and Benjamin Franklin Bridges. The cleared site was previously used for industrial purposes and has a G-2 industrial zoning. Adverse impacts during the construction phase of the project are not expected to be significantly different than those occurring during any major industrial construction project. During operation of the coal gasification facility, specific mitigative measures have been designed into the facility to avoid adverse environmental impacts wherever possible. In addition to these extensive engineeringmore » safeguards, elaborate monitoring and control instrumentation shall be used. The GKT entrained bed, oxygen-blown gasification process provided by Krupp/Koppers was selected because it is a commercially proven system and because of its positive environmental characteristics such as its ability to gasify many coal types and the fact that it does not produce tars, phenols, or ammonia. During gasification of the coal, pollutants such as heavy metals in the coal are concentrated into the slag and ash. None of these pollutants are found in the product gas. The facility will produce 250 tpd of non-hazardous slag and fly ash. The combined slag and fly ash will occupy 347 cubic yards per day of landfill volume. Available haulers and landfills have been identified.A sophisticated health and safety program will include appropriate monitoring instruments for CO, H/sub 2/, H/sub 2/S, polynuclear aromatic hydrocarbons, organic compounds, and coal dust. Air emissions from operation of the coal gasification plant are not considered significant. Dust control systems have been designed into the facility to minimize fugitive dust emissions.« less

TRACE METAL TRANSFORMATION MECHANISMS DURING COAL COMBUSTION

EPA Science Inventory

The article reviews mechanisms governing the fate of trace metals during coal combustion and presents new theoretical results that interpret existing data. Emphasis is on predicting the size-segregated speciation of trace metals in pulverized-coal-fired power plant effluents. Thi...

Stochastic Modelling of the Hydraulic Anisotropy of Ash Impoundment Sediment

NASA Astrophysics Data System (ADS)

Slávik, Ivan

2017-12-01

In the case reported here the impoundments of a 400 MW coal heated power plant with an annual production of about 1.5 million tons of fuel ash are of the cross-valley type, operated by the simple and cheap „upstream method”. The aim of the research was to determine overall and local values of the permeability in horizontal as well as in vertical direction and the anisotropy of the thin-layered sedimented ash. The coal ashes are hydraulically transported through pipelines in form of a slurry and periodically floated on the beach of the impoundment. The ashes are deposited in the form of a thin-layered sediment, with random alternation of layers with a coarser or finer granularity. The ash impoundment sediment is anthropogenic sediment with horizontally laminated texture. Therefore, the sediment is anisotropic from the viewpoint of water seepage. The knowledge of the permeability and the seepage anisotropy of the sediment is a basic requirement for the design of an appropriate dewatering system. The seepage anisotropy of the ash sediment has been checked by means of stochastic modelling, based on the correlation between the effective grain diameter and the coefficient of permeability of the ash: the effective grain diameter and the thickness of individual layers have been proposed to be random events.

Clean up fly ash from coal burning plants by new isolated fungi Fusarium oxysporum and Penicillium glabrum.

PubMed

Ertit Taştan, Burcu

2017-09-15

In Turkey approximately 45 million tons of coals are burned in a year and 19.3 million tons of fly ash have emerged. The bioremediation of heavy metals or different elements from fly ash makes them bio-available. However, in previous studies, requiring of long operational time and failing to show tolerance to high pulp densities of fly ash of selected fungal species makes them impractical. In this work, bioremediation of fly ash by new isolated fungi Fusarium oxysporum and Penicillium glabrum were investigated in one step and two step bioremediation process. Ca, Si, Fe and S were found to be considerable amount in studied fly ashes by ED-XRF element analysis. The bioremediation yields of Mo (100%), S (64.36%) Ni (50%) and Cu (33.33%) by F. oxysporum were high. The remediated elements by P. glabrum in fly ash were Mo (100%), S (57.43%), Ni (25%), Si (24.66%), V (12.5%), Ti (5%) and Sr (3.2%). The isolation of high fly ash resistant fungi and reduction of the bioremediation time will allow the practical applications of the bioremediation technology when it is scaled up. Copyright © 2017 Elsevier Ltd. All rights reserved.

EVALUATION OF THE EFFECTS OF COAL FLY ASH AMENDMENTS ON THE TOXICITY OF A CONTAMINATED MARINE SEDIMENT

PubMed Central

Burgess, Robert M.; Perron, Monique M.; Friedman, Carey L.; Suuberg, Eric M.; Pennell, Kelly G.; Cantwell, Mark G.; Pelletier, Marguerite C.; Ho, Kay T.; Serbst, Jonathan R.; Ryba, Stephan A.

2013-01-01

Approaches for cleaning-up contaminated sediments range from dredging to in situ treatment. In the present report, we discuss the effects of amending reference and contaminated sediments with coal fly ash to reduce the bioavailability and toxicity of a field sediment contaminated with polycyclic aromatic hydrocarbons (PAHs). Six fly ashes and a coconut charcoal were evaluated in 7 d whole sediment toxicity tests with a marine amphipod (Ampelisca abdita) and mysid (Americamysis bahia). Fly ashes with high carbon content and the coconut charcoal showed proficiency at reducing toxicity. Some of the fly ashes demonstrated toxicity in the reference treatments. It is suspected that some of this toxicity is related to the presence of ammonia associated with fly ashes as a result of post-oxidation treatment to reduce nitrous oxides emissions. Relatively simple methods exist to remove ammonia from fly ash prior to use and fly ashes with low ammonia content are available. Fly ashes were also shown to effectively reduce overlying water concentrations of several PAHs. There was no evidence of the release of the metals cadmium, copper, nickel or lead from the fly ashes. A preliminary 28 d polychaete bioaccumulation study with one of the high carbon fly ashes and a reference sediment was also performed. Although preliminary, there was no evidence of adverse effects to worm growth or lipid content, or the accumulation of PAHs or mercury from exposure to the fly ash. These data show fly ashes with high carbon contents may represent viable remedial materials for reducing the bioavailability of organic contaminants in sediments. PMID:18717615

Characterization of Coal Combustion Residues from Electric Utilities--Leaching and Characterization Data

EPA Science Inventory

This report evaluates changes in composition and constituent release by leaching that may occur to fly ash and other coal combustion residues (CCRs) in response to changes in air pollution control technology at coal-fired power plants. The addition of flue-gas desulfurization (FG...

Process for removing pyritic sulfur from bituminous coals

DOEpatents

Pawlak, Wanda; Janiak, Jerzy S.; Turak, Ali A.; Ignasiak, Boleslaw L.

1990-01-01

A process is provided for removing pyritic sulfur and lowering ash content of bituminous coals by grinding the feed coal, subjecting it to micro-agglomeration with a bridging liquid containing heavy oil, separating the microagglomerates and separating them to a water wash to remove suspended pyritic sulfur. In one embodiment the coal is subjected to a second micro-agglomeration step.

Process for converting coal into liquid fuel and metallurgical coke

DOEpatents

Wolfe, Richard A.; Im, Chang J.; Wright, Robert E.

1994-01-01

A method of recovering coal liquids and producing metallurgical coke utilizes low ash, low sulfur coal as a parent for a coal char formed by pyrolysis with a volatile content of less than 8%. The char is briquetted and heated in an inert gas over a prescribed heat history to yield a high strength briquette with less than 2% volatile content.

Reducing power production costs by utilizing petroleum coke. Annual report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Galbreath, K.C.

1998-07-01

A Powder River Basin subbituminous coal from the North Antelope mine and a petroleum shot coke were received from Northern States Power Company (NSP) for testing the effects of parent fuel properties on coal-coke blend grindability and evaluating the utility of petroleum coke blending as a strategy for improving electrostatic precipitator (ESP) particulate collection efficiency. Petroleum cokes are generally harder than coals, as indicated by Hardgrove grindability tests. Therefore, the weaker coal component may concentrate in the finer size fractions during the pulverizing of coal-coke blends. The possibility of a coal-coke size fractionation effect is being investigated because it maymore » adversely affect combustion performance, it may enhance ESP particulate collection efficiency. Petroleum cokes contain much higher concentrations of V relative to coals. Consequently, coke blending can significantly increase the V content of fly ash resulting from coal-coke combustion. Pentavalent vanadium oxide (V{sub 2}O{sub 5}) is a known catalyst for transforming gaseous sulfur dioxide (SO{sub 2}[g]) to gaseous sulfur trioxide (SO{sub 3}[g]). The presence of SO{sub 3}(g) strongly affects fly ash resistivity and, thus, ESP performance.« less

Contents and occurrence of cadmium in the coals from Guizhou province, China.

PubMed

Song, Dangyu; Wang, Mingshi; Zhang, Junying; Zheng, Chuguang

2008-10-01

Eleven raw coal samples were collected from Liuzhi, Suicheng, Zunyi, Xingren, Xingyi, and Anlong districts in Guizhou Province, Southwest China. The content of cadmium (Cd) in coal was determined using inductively coupled plasma mass-spectrometry (ICP-MS). Cd contents ranged from 0.146 to 2.74 ppm (whole coal basis), with an average of 1.09 ppm. In comparison with the arithmetic means of Cd in Chinese coal (0.25 ppm), this is much higher. In order to find its occurrence in coal, float-sink analysis and a coal flotation test by progressive release were conducted on two raw coal samples. The content of the Cd and ash yield of the flotation products were determined. The organic matter was removed by low-temperature ashing (LTA). X-ray diffraction (XRD) was used to differentiate the main, minor, and trace minerals in the LTA from different flotation subproducts. Quartz, kaolinite, pyrite, and calcite were found to dominate the mineral matters, with a proportion of anatase, muscovite, and illite. Then quantitative analysis of minerals in LTA was conducted using material analysis using diffraction (MAUD) based on the Rietveld refinement method. Results show that Cd has a strong association with kaolinite.

Trace elements by instrumental neutron activation analysis for pollution monitoring

NASA Technical Reports Server (NTRS)

Sheibley, D. W.

1975-01-01

Methods and technology were developed to analyze 1000 samples/yr of coal and other pollution-related samples. The complete trace element analysis of 20-24 samples/wk averaged 3-3.5 man-hours/sample. The computerized data reduction scheme could identify and report data on as many as 56 elements. In addition to coal, samples of fly ash, bottom ash, crude oil, fuel oil, residual oil, gasoline, jet fuel, kerosene, filtered air particulates, ore, stack scrubber water, clam tissue, crab shells, river sediment and water, and corn were analyzed. Precision of the method was plus or minus 25% based on all elements reported in coal and other sample matrices. Overall accuracy was estimated at 50%.

Complete physico-chemical treatment for coke plant effluents.

PubMed

Ghose, M K

2002-03-01

Naturally found coal is converted to coke which is suitable for metallurgical industries. Large quantities of liquid effluents produced contain a large amount of suspended solids, high COD, BOD, phenols, ammonia and other toxic substances which are causing serious pollution problem in the receiving water to which they are discharged. There are a large number of coke plants in the vicinity of Jharia Coal Field (JCF). Characteristics of the effluents have been evaluated. The present effluent treatment systems were found to be inadequate. Physico-chemical treatment has been considered as a suitable option for the treatment of coke plant effluents. Ammonia removal by synthetic zeolite, activated carbon for the removal of bacteria, viruses, refractory organics, etc. were utilized and the results are discussed. A scheme has been proposed for the complete physico-chemical treatment, which can be suitably adopted for the recycling, reuse and safe disposal of the treated effluent. Various unit process and unit operations involved in the treatment system have been discussed. The process may be useful on industrial scale at various sites.

Engineering Behavior and Characteristics of Wood Ash and Sugarcane Bagasse Ash

PubMed Central

Grau, Francisco; Choo, Hyunwook; Hu, Jong Wan; Jung, Jongwon

2015-01-01

Biomasses are organic materials that are derived from any living or recently-living structure. Plenty of biomasses are produced nationwide. Biomasses are mostly combusted and usually discarded or disposed of without treatment as biomass ashes, which include wood and sugarcane bagasse ashes. Thus, recycling or treatment of biomass ashes leads to utilizing the natural materials as an economical and environmental alternative. This study is intended to provide an environmental solution for uncontrolled disposal of biomass ashes by way of recycling the biomass ash and replacing the soils in geotechnical engineering projects. Therefore, in this study, characteristic tests of wood and sugarcane bagasse ashes that are considered the most common biomass ashes are conducted. The test of chemical compositions of biomass ashes is conducted using energy dispersive X-ray spectroscopy (EDS), and Scanning Electron Microscope (SEM), and heavy metal analysis is also conducted. Engineering behaviors including hydraulic conductivity, constrained modulus and shear modulus are examined. Also, coal fly ash Class C is used in this study for comparison with biomass ashes, and Ottawa 20/30 sands containing biomass ashes are examined to identify the soil replacement effect of biomass ashes. The results show that the particle sizes of biomass ashes are halfway between coal fly ash Class C and Ottawa 20/30 sand, and biomass ashes consist of a heterogeneous mixture of different particle sizes and shapes. Also, all heavy metal concentrations were found to be below the US Environmental Protection Agency (EPA) maximum limit. Hydraulic conductivity values of Ottawa 20/30 sand decrease significantly when replacing them with only 1%–2% of biomass ashes. While both the constrained modulus and shear modulus of biomass ashes are lower than Ottawa 20/30 sand, those of mixtures containing up to 10% biomass ashes are little affected by replacing the soils with biomass ashes. PMID:28793611

A fouling monitor alarm to prevent forced outages

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thompson, R.E.; Hickinbotham, A.; Fang, T.C.

2000-07-01

Many utilities rely on coal blending to meet emissions and boiler performance goals, but the increased variability in coal quality can adversely impact ash deposition and soot blowing requirements. Other utilities are experimenting with lower quality coals and burner zone blending of coals fired from different bunkers as part of a deregulation strategy to reduce fuel costs. However, these strategies can lead to slagging/fouling episodes, a possible outage, or a decrease in unit availability if boiler operations are not carefully monitored. This paper summarizes the development of software to monitor boiler fouling and to provide an advanced warning to themore » control operators when a fouling episode is imminent. With adequate warming, preemptive action can be taken (e.g., soot blowing, a change in coal blend, etc.) to potentially avoid a costly outage. The software utilizes a unique combination of combustion diagnostic techniques and convective section heat adsorption analyses to identify boiler operating conditions where ash deposition rates may be high and conductive to triggering a fouling episode. The paper outlines the history of the fouling problem and the implementation of the software on Wabamun Unit 4, a tangentially-fired unit with relatively narrow reheat tube spacing. The unit had a tendency to foul when burning a high alkaline (but low ash) coal seam. The paper discusses the software development, implementation, and data acquisitions activities. Preliminary test results are provided for Wabamun 4 and for Sundance Units 1 and 2 where the software was recently installed.« less

Short-Term Exposure to Coal Combustion Waste Has Little Impact on the Skin Microbiome of Adult Spring Peepers (Pseudacris crucifer)

PubMed Central

Walke, Jenifer B.; Becker, Matthew H.; Umile, Thomas P.; Burzynski, Elizabeth A.; Minbiole, Kevin P. C.; Iannetta, Anthony A.; Santiago, Celina N.; Hopkins, William A.; Belden, Lisa K.

2016-01-01

ABSTRACT Disruptions to the microbiome can impact host health as can exposure to environmental contaminants. However, few studies have addressed how environmental contaminants impact the microbiome. We explored this question for frogs that breed in wetlands contaminated with fly ash, a by-product of coal combustion that is enriched in trace elements. We found differences in the bacterial communities among a fly ash-contaminated site and several reference wetlands. We then experimentally assessed the impacts of fly ash on the skin microbiome of adult spring peepers (Pseudacris crucifer). Frogs were exposed to fly ash in the laboratory for 12 h, the duration of a typical breeding event, and the skin microbiome was assessed after 5 days (experiment 1) or after 5 and 15 days (experiment 2). We examined bacterial community structure using 16S rRNA gene amplicon sequencing and metabolite profiles using high-pressure liquid chromatography-mass spectrometry (HPLC-MS). We found little impact as the result of acute exposure to fly ash on the bacterial communities or metabolite profiles in either experiment, suggesting that the bacterial symbiont communities of adults may be relatively resistant to brief contaminant exposure. However, housing frogs in the laboratory altered bacterial community structure in the two experiments, which supports prior research suggesting that environmental source pools are important for maintaining the amphibian skin microbiome. Therefore, for contaminants like fly ash that may alter the potential source pool of symbionts, we think it may be important to explore how contaminants affect the initial assembly of the amphibian skin microbiome in larval amphibians that develop within contaminated sites. IMPORTANCE Animals are hosts to many symbiotic microorganisms, collectively called the microbiome, that play critical roles in host health. Therefore, environmental contaminants that alter the microbiome may impact hosts. Some of the most widespread contaminants, produced worldwide, are derived from the mining, storage, and combustion of coal for energy. Fly ash, for example, is a by-product of coal combustion. It contains compounds such as arsenic, selenium, cadmium, and strontium and is a recognized source of ground and surface water contamination. Here, we experimentally investigated the impacts of short-term fly ash exposure on the skin microbiome of spring peepers, one of many species of amphibian that sometimes breed in open fly ash disposal ponds. This research provides a look into the potential impacts of fly ash on an animal's microbiome and suggests important future directions for research on the effects of environmental contaminants on the microbiome. PMID:27037118

Spatial and temporal trends in contaminant concentrations in Hexagenia nymphs following a coal ash spill at the Tennessee Valley Authority's Kingston Fossil Plant

DOE PAGES

Baker, Tyler F; Jett, Robert Trent; Smith, John G.; ...

2016-02-25

A dike failure at the Tennessee Valley Authority Kingston Fossil Plant in East Tennessee, United States, in December 2008, released approximately 4.1 million m3 of coal ash into the Emory River. From 2009 through 2012, samples of mayfly nymphs ( Hexagenia bilineata) were collected each spring from sites in the Emory, Clinch, and Tennessee Rivers upstream and downstream of the spill. Samples were analyzed for 17 metals. Concentrations of metals were generally highest the first 2 miles downstream of the spill, and then decreased with increasing distance from the spill. Arsenic, B, Ba, Be, Mo, Sb, Se, Sr, and Vmore » appeared to have strong ash signatures, whereas Co, Cr, Cu, Ni, and Pb appeared to be associated with ash and other sources. Furthermore, the concentrations for most of these contaminants were modest and are unlikely to cause widespread negative ecological effects. Trends in Hg, Cd, and Zn suggested little (Hg) or no (Cd, Zn) association with ash. Temporal trends suggested that concentrations of ash-related contaminants began to subside after 2010, but because of the limited time period of that analysis (4 yr), further monitoring is needed to verify this trend. The present study provides important information on the magnitude of contaminant exposure to aquatic receptors from a major coal ash spill, as well as spatial and temporal trends for transport of the associated contaminants in a large open watershed. Environ Toxicol Chem 2016;35:1159 1171. Published 2015 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.« less

Heavy metal leaching from coal fly ash amended container substrates during Syngonium production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Q.S.; Chen, J.J.; Li, Y.C.

2008-02-15

Coal fly ash has been proposed to be an alternative to lime amendment and a nutrient source of container substrates for ornamental plant production. A great concern over this proposed beneficial use, however, is the potential contamination of surface and ground water by heavy metals. In this study, three fly ashes collected from Florida, Michigan, and North Carolina and a commercial dolomite were amended in a basal substrate. The formulated substrates were used to produce Syngonium podophyllum Schott 'Berry Allusion' in 15-cm diameter containers in a shaded greenhouse. Leachates from the containers were collected during the entire six months ofmore » plant production and analyzed for heavy metal concentrations. There were no detectable As, Cr, Hg, Pb, and Se in the leachates; Cd and Mo were only detected in few leachate samples. The metals constantly detected were Cu, Mn, Ni, and Zn. The total amounts of Cu, Mn, Ni, and Zn leached during the six-month production period were 95, 210, 44, and 337 {mu} g per container, indicating that such amounts in leachates may contribute little to contamination of surface and ground water. In addition, plant growth indices and fresh and dry weights of S. podophyllum 'Berry Allusion' produced from fly ash and dolomite-amended substrates were comparable except for the plants produced from the substrate amended with fly ash collected from Michigan which had reduced growth indices and fresh and dry weights. Thus, selected fly ashes can be alternatives to commercial dolomites as amendments to container substrates for ornamental plant production. The use of fly ashes as container substrate amendments should represent a new market for the beneficial use of this coal combustion byproduct.« less

Enhancement of mercury capture by the simultaneous addition of hydrogen bromide (HBr) and fly ashes in a slipstream facility.

PubMed

Cao, Yan; Wang, Quan-Hai; Li, Jun; Cheng, Jen-Chieh; Chan, Chia-Chun; Cohron, Marten; Pan, Wei-Ping

2009-04-15

Low halogen content in tested Powder River Basin (PRB) coals and low loss of ignition content (LOI) in PRB-derived fly ash were likely responsible for higher elemental mercury content (averaging about 75%) in the flue gas and also lower mercury capture efficiency by electrostatic precipitator (ESP) and wet-FGD. To develop a cost-effective approach to mercury capture in a full-scale coal-fired utility boiler burning PRB coal, experiments were conducted adding hydrogen bromide (HBr) or simultaneously adding HBr and selected fly ashes in a slipstream reactor (0.152 x 0.152 m) under real flue gas conditions. The residence time of the flue gas inside the reactorwas about 1.4 s. The average temperature of the slipstream reactor was controlled at about 155 degrees C. Tests were organized into two phases. In Phase 1, only HBr was added to the slipstream reactor, and in Phase 2, HBr and selected fly ash were added simultaneously. HBr injection was effective (>90%) for mercury oxidation at a low temperature (155 degrees C) with an HBr addition concentration of about 4 ppm in the flue gas. Additionally, injected HBr enhanced mercury capture by PRB fly ash in the low-temperature range. The mercury capture efficiency, attesting conditions of the slipstream reactor, reached about 50% at an HBr injection concentration of 4 ppm in the flue gas. Compared to only the addition of HBr, simultaneously adding bituminous-derived fly ash in a minimum amount (30 lb/MMacf), together with HBr injection at 4 ppm, could increase mercury capture efficiency by 30%. Injection of lignite-derived fly ash at 30 lb/MMacf could achieve even higher mercury removal efficiency (an additional 35% mercury capture efficiency compared to HBr addition alone).

The Effects of Bottom Ash on Setting Time and Compressive Strength of Fly Ash Geopolymer Paste

NASA Astrophysics Data System (ADS)

Affandhie, B. A.; Kurniasari, P. T.; Darmawan, M. S.; Subekti, S.; Wibowo, B.; Husin, N. A.; Bayuaji, R.; Irawan, S.

2017-11-01

This research is to find out the contribution of waste energy utilization of fly ash and bottom ash coal as binding agent of geopolymer concrete. This research methodology uses experimental approach in laboratory by making cylinder paste test object with dimension diameter of 2.5 cm x height 5 cm with some combination of fly ash and bottom ash mix with time setting test (ASTM C 191-04a) and compressive strength (ASTM C 39-04a). The research concludes that the effect of bottom ash on fly ash-based geopolymer paste shows good results in setting time and compressive strength.

Emissions During Co-Firing of RDF-5 with Coal in a 22 t/h Steam Bubbling Fluidized Bed Boiler

NASA Astrophysics Data System (ADS)

Wan, Hou-Peng; Chen, Jia-Yuan; Juch, Ching-I.; Chang, Ying-Hsi; Lee, Hom-Ti

The co-firing of biomass and fossil fuel in the same power plant is one of the most important issues when promoting the utilization of renewable energy in the world. Recently, the co-firing of coal together with biomass fuel, such as "densified refuse derived fuel" (d-RDF or RDF-5) or RPF (refuse paper & plastic fuel) from waste, has been considered as an environmentally sound and economical approach to both waste remediation and energy production in the world. Because of itscomplex characteristics when compared to fossil fuel, potential problems, such as combustion system stability, the corrosion of heat transfer tubes, the qualities of the ash, and the emissionof pollutants, are major concerns when co-firing the biomass fuel with fossil fuel in a traditional boiler. In this study, co-firing of coal with RDF-5 was conducted in a 22t/h bubbling fluidized bed (BFB) steam boiler to investigate the feasibility of utilizing RDF-5 as a sustainable fuels in a commercial coal-fired steam BFB boiler. The properties of the fly ash, bottom ash, and the emission of pollutants are analyzed and discussed in this study.

Coal combustion products: trash or treasure?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hansen, T.

2006-07-15

Coal combustion by-products can be a valuable resource to various industries. The American Coal Ash Association (ACAA) collects data on production and uses of coal combustion products (CCPs). 122.5 million tons of CCPs were produced in 2004. The article discusses the results of the ACCA's 2004 survey. Fly ash is predominantly used as a substitute for Portland cement; bottom ash for structural fill, embankments and paved road cases. Synthetic gypsum from the FGD process is commonly used in wallboard. Plant owners are only likely to have a buyer for a portion of their CCPs. Although sale of hot water (frommore » Antelope Valley Station) from condensers for use in a fish farm to raise tilapia proved unviable, the Great Plains Synfuels Plant which manufactures natural gas from lignite produces a wide range of products including anhydrous ammonia, phenol, krypton, carbon dioxide (for enhanced oil recovery), tar oils and liquid nitrogen. ACCA's goal is to educate people about CCPs and how to make them into useful products, and market them, in order to reduce waste disposal and enhance revenue. The article lists members of the ACCA. 2 photos., 1 tab.« less

The measurement of unburned carbon in fly ash using infrared photoacoustics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Waller, D.J.; Brown, R.C.

1995-12-31

Unburned carbon in fly ash yields valuable information on coal combustion efficiency in coal-fired boilers. The carbon content of fly ash is also an important parameters in the sale of fly ash for Portland cement. Unfortunately, a reliable and inexpensive instrument for measuring unburned carbon is not commercially available. The authors have developed an off-line instrument that detects carbon in fly ash via the photoacoustic effect. In this process, amplitude-modulated radiation is absorbed by a bulk sample of fly ash. The wavelength of the radiation is chosen such that mineral compounds and moisture in the fly ash are transparent tomore » the radiation but carbon is strongly absorbing. The modulated absorption generates a periodic pressure wave at the surface of the sample which propagates through the surrounding air as an acoustic wave. This wave is detected by a sensitive microphone, and is dependent on the carbon content of the sample. The resulting instrument has been used to measure fly ash carbon concentrations from less than 0.1% to nearly 7% by mass. The precision of these measurements is nominally within 4%, which is equivalent to the precision of the chemical analysis used to develop the calibration standards. The applicability of a theoretical model to the empirical results is discussed with respect to fly ash sample preparation.« less

Fate and aqueous transport of mercury in light of the Clean Air Mercury Rule for coal-fired electric power plants

NASA Astrophysics Data System (ADS)

Arzuman, Anry

Mercury is a hazardous air pollutant emitted to the atmosphere in large amounts. Mercury emissions from electric power generation sources were estimated to be 48 metric tons/year, constituting the single largest anthropogenic source of mercury in the U.S. Settled mercury species are highly toxic contaminants of the environment. The newly issued Federal Clean Air Mercury Rule requires that the electric power plants firing coal meet the new Maximum Achievable Mercury Control Technology limit by 2018. This signifies that all of the air-phase mercury will be concentrated in solid phase which, based on the current state of the Air Pollution Control Technology, will be fly ash. Fly ash is utilized by different industries including construction industry in concrete, its products, road bases, structural fills, monifills, for solidification, stabilization, etc. Since the increase in coal combustion in the U.S. (1.6 percent/year) is much higher than the fly ash demand, large amounts of fly ash containing mercury and other trace elements are expected to accumulate in the next decades. The amount of mercury transferred from one phase to another is not a linear function of coal combustion or ash production, depends on the future states of technology, and is unknown. The amount of aqueous mercury as a function of the future removal, mercury speciation, and coal and aquifer characteristics is also unknown. This paper makes a first attempt to relate mercury concentrations in coal, flue gas, fly ash, and fly ash leachate using a single algorithm. Mercury concentrations in all phases were examined and phase transformation algorithms were derived in a form suitable for probabilistic analyses. Such important parameters used in the transformation algorithms as Soil Cation Exchange Capacity for mercury, soil mercury selectivity sequence, mercury activity coefficient, mercury retardation factor, mercury species soil adsorption ratio, and mercury Freundlich soil adsorption isotherm coefficients were derived. Mercury air-phase removal efficiency was studied as a function of dominant mercury species vapor pressures, the amount of chlorine, sorbent injection rate and adsorption capacities, and process temperature and modifications. A mercury air phase removal algorithm was derived which defines the future removal efficiencies as a function of activated carbon injection rate. Mercury adsorption on soil was studied as a function of Mercury Mass Law incorporating the dominant aquatic mercury species, pH, chlorine and sulfur concentrations, and the amount of complexed hydroxyl groups. Aquatic mercury longitudinal plume delineation was studied using the Domenico and Robbins function. A Monte Carlo simulation was performed using random number series (5000) for all of the variables in the Domenico and Robbins and mercury retardation functions. The probability that the Maximum Contaminant Level for mercury will be exceeded was found to be equal approximately 1 percent of all soil-related fly ash applications.

COAL SULFUR MEASUREMENTS

EPA Science Inventory

The report describes a new technique for sulfur forms analysis based on low-temperature oxygen plasma ashing. The technique involves analyzing the low-temperature plasma ash by modified ASTM techniques after selectively removing the organic material. The procedure has been tested...

Carbon-enriched coal fly ash as a precursor of activated carbons for SO2 removal.

PubMed

Izquierdo, M T; Rubio, B

2008-06-30

Carbon-enriched coal fly ash was evaluated in this work as a low-cost adsorbent for SO2 removal from stack gases. The unburned carbon in coal fly ash was concentrated by mechanical sieving and vegetal oil agglomeration. The carbon concentrates were activated with steam at 900 degrees C in order to develop porosity onto the samples. The performance of these samples in the SO2 abatement was tested in the following conditions: 100 degrees C, 1000 ppmv SO2, 5% O2, 6% water vapor. A good SO2 removal capacity was shown by some of the studied samples that can be related to their textural properties. Cycles of SO2 adsorption/regeneration were carried out in order to evaluate the possibility of thermal regeneration and re-use of these carbons. Regeneration of the exhausted carbons was carried out at 400 degrees C of temperature and a flow of 25 ml/min of Ar. After each cycle, the SO2 removal capacity of the sample decreases.

Exploring metal detoxification and accumulation potential during vermicomposting of Tea factory coal ash: sequential extraction and fluorescence probe analysis

PubMed Central

Goswami, Linee; Pratihar, Sanjay; Dasgupta, Suman; Bhattacharyya, Pradip; Mudoi, Pronab; Bora, Jayanta; Bhattacharya, Satya Sundar; Kim, Ki Hyun

2016-01-01

Metal contamination from coal ashes (CAs) is widely recognized as a significant environmental concern. To learn more about metal detoxification and accumulation potential of earthworm species, metal-rich tea factory coal ashes (TFCA) were fed to Eisenia fetida and Lampito mauritii by employing a fluorescent tag detection method. Fascinatingly, on feeding fluorescence probed Zn and Cd along with cow dung to Eisenia fetida, the detection of the gut-proteins with a molecular mass higher than 100 kDa was a distinct evidence of metal binding. Significant increases were observed in the content of humified organic C [humic acid (HAC) and fulvic acid C (FAC)] and degree of humification during vermicomposting. Concurrently, considerably large amount of toxic metals (Cr, Cd, Pb, and Zn) was transformed from exchangeable to recalcitrant (organic matter and mineral bound) fractions. Moreover, total metal concentrations were reduced with high removal efficiency upon vermicomposting. PMID:27456167

Effects of pyrolysis temperature, time and leaf litter and powder coal ash addition on sludge-derived adsorbents for nitrogen oxide.

PubMed

Ren, Xiaoli; Liang, Baohong; Liu, Min; Xu, Xiaoyuan; Cui, Meihua

2012-12-01

The objective of this research was to seek a cost effective solution to prepare adsorbents for nitrogen oxide from surplus sludge. Leaf litter and powder coal ash were used as cheap and easily available additives. An adsorbent for nitrogen oxide was prepared by pyrolysis of dried sludge mixed with zinc chloride. Under optimum pyrolysis conditions of 375°C for 90 min and a zinc chloride content of 30%, the surface area of the adsorbent with leaf litter was 514.41 m(2)/g, the surface area of the adsorbent with powder coal ash was 432.34 m(2)/g, respectively, corresponding to an increase of 90.70% and 60.27% when compared to the adsorbent without the additives. The saturated adsorption quantity of the adsorbent with leaf litter reached 271 mg/g at 20°C. The results indicated that the sludge-derived adsorbent was quite promising for nitrogen oxide removal. Copyright © 2012 Elsevier Ltd. All rights reserved.

Characterization of humidity-controlling porous ceramics produced from coal fly ash and waste catalyst by co-sintering

NASA Astrophysics Data System (ADS)

Lin, Kae-Long; Ma, Chih-Ming; Lo, Kang-Wei; Cheng, Ta-Wui

2018-04-01

In this study, the following operating conditions were applied to develop humidity-controlling porous ceramic (HCPC) products: sintering temperatures of 800-1000 °C and percentages of coal fly ash in waste catalyst of 0%-40%. The HCPC samples then underwent a flexural strength test, to determine their quality according to the Chinese National Standards (CNS 3298). Their microstructures, crystal structures, and pore volume were determined in terms of equilibrium moisture content, water vapor adsorption/desorption, and hygroscopic sorption properties over 48 h. Nitrogen adsorption/desorption isotherms showed a hydrophobic behavior (type H3 isotherm). The water vapor adsorption/desorption and hygroscopic sorption properties satisfied the JIS A1470 intensity specification for building materials (>29 g/m2). At sintering temperatures of 950-1000 °C, HCPC samples for coal fly ash containing 20%-30% waste catalyst met the JIS A1470 intensity specifications for building materials (<29 g/m2).

Environmental chamber measurements of mercury flux from coal utilization by-products

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pekney, Natalie J.; Martello, Donald; Schroeder, Karl

2009-05-01

An environmental chamber was constructed to measure the mercury flux from coal utilization by-product (CUB) samples. Samples of fly ash, FGD gypsum, and wallboard made from FGD gypsum were tested under both dark and illuminated conditions with or without the addition of water to the sample. Mercury releases varied widely, with 7- day experiment averages ranging from -6.8 to 73 ng/m(2) h for the fly ash samples and -5.2 to 335 ng/m(2) h for the FGD/wallboard samples. Initial mercury content, fly ash type, and light exposure had no observable consistent effects on the mercury flux. For the fly ash samples,more » the effect of a mercury control technology was to decrease the emission. For three of the four pairs of FGD gypsum and wallboard samples, the wallboard sample released less (or absorbed more) mercury than the gypsum.« less

Environmental chamber measurements of mercury flux from coal utilization by-products

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pekney, N.J.; Martello, D.V.; Schroeder, K.T.

2009-05-01

An environmental chamber was constructed to measure the mercury flux from coal utilization by-product (CUB) samples. Samples of fly ash, FGD gypsum, and wallboard made from FGD gypsum were tested under both dark and illuminated conditions with or without the addition of water to the sample. Mercury releases varied widely, with 7-day experiment averages ranging from -6.8 to 73 ng/m2 h for the fly ash samples and -5.2 to 335 ng/m2 h for the FGD/wallboard samples. Initial mercury content, fly ash type, and light exposure had no observable consistent effects on the mercury flux. For the fly ash samples, themore » effect of a mercury control technology was to decrease the emission. For three of the four pairs of FGD gypsum and wallboard samples, the wallboard sample released less (or absorbed more) mercury than the gypsum.« less

Bottom ash boosts poor soil

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stanley, D.

1993-04-01

This article describes agricultural uses of fluidized bed bottom ash residue from burning limestone and coal in electric power generating plants: as a limestone substitute, to increase calcium levels in both soil and plants, and as a gypsom-containing soil amendment. Apples and tomatoes are the crops used. The industrial perspective and other uses of bottom ash are also briefly described.

Characterizations of Deposited Ash During Co-Firing of White Pine and Lignite in Fluidized Bed Combustor

NASA Astrophysics Data System (ADS)

Shao, Yuanyuan; Zhu, Jesse; Preto, Fernando; Tourigny, Guy; Wang, Jinsheng; Badour, Chadi; Li, Hanning; Xu, Chunbao Charles

Characterizations of ash deposits from co-firing/co-combusting of a woody biomass (i.e., white pine) and lignite coal were investigated in a fluidized-bed combustor using a custom designed air-cooled probe installed in the freeboard region of the reactor. Ash deposition behaviors on a heat transfer surface were comprehensively investigated and discussed under different conditions including fuel type, fuel blending ratios (20-80% biomass on a thermal basis), and moisture contents. For the combustion of 100% lignite, the compositions of the deposited ash were very similar to those of the fuel ash, while in the combustion of 100% white pine pellets or sawdust the deposited ash contained a much lower contents of CaO, SO3, K2O and P2O5 compared with the fuel ash, but the deposited ash was enriched with SiO2, Al2O3 and MgO. A small addition of white pine (20% on a heat input basis) to the coal led to the highest ash deposition rates likely due to the strong interaction of the CaO and MgO (from the biomass ash) with the alumina and silica (from the lignite ash) during the co-combustion process, evidenced by the detection of high concentrations of calcium/magnesium sulfates, aluminates and silicates in the ash deposits. Interestingly, co-firing of white pine pellets and lignite at a 50% blending ratio led to the lowest ash deposition rates. Ash deposition rates in combustion of fuels as received with a higher moisture content was found to be much lower than those of oven-dried fuels.

Boiler Briquette Coal versus Raw Coal: Part II-Energy, Greenhouse Gas, and Air Quality Implications.

PubMed

Zhang, Junfeng; Ge, Su; Bai, Zhipeng

2001-04-01

The objective of this paper is to conduct an integrated analysis of the energy, greenhouse gas, and air quality impacts of a new type of boiler briquette coal (BB-coal) in contrast to those of the raw coal from which the BB-coal was formulated (R-coal). The analysis is based on the source emissions data and other relevant data collected in the present study and employs approaches including the construction of carbon, energy, and sulfur balances. The results show that replacing R-coal with BB-coal as the fuel for boilers such as the one tested would have multiple benefits, including a 37% increase in boiler thermal efficiency, a 25% reduction in fuel demand, a 26% reduction in CO 2 emission, a 17% reduction in CO emission, a 63% reduction in SO 2 emission, a 97% reduction in fly ash and fly ash carbon emission, a 22% reduction in PM 2.5 mass emission, and a 30% reduction in total emission of five toxic hazardous air pollutant (HAP) metals contained in PM 10 . These benefits can be achieved with no changes in boiler hardware and with a relatively small amount of tradeoffs: a 30% increase in PM 10 mass emission and a 9-16% increase in fuel cost.

Boiler briquette coal versus raw coal: Part II--Energy, greenhouse gas, and air quality implications.

PubMed

Zhang, J; Ge, S; Bai, Z

2001-04-01

The objective of this paper is to conduct an integrated analysis of the energy, greenhouse gas, and air quality impacts of a new type of boiler briquette coal (BB-coal) in contrast to those of the raw coal from which the BB-coal was formulated (R-coal). The analysis is based on the source emissions data and other relevant data collected in the present study and employs approaches including the construction of carbon, energy, and sulfur balances. The results show that replacing R-coal with BB-coal as the fuel for boilers such as the one tested would have multiple benefits, including a 37% increase in boiler thermal efficiency, a 25% reduction in fuel demand, a 26% reduction in CO2 emission, a 17% reduction in CO emission, a 63% reduction in SO2 emission, a 97% reduction in fly ash and fly ash carbon emission, a 22% reduction in PM2.5 mass emission, and a 30% reduction in total emission of five toxic hazardous air pollutant (HAP) metals contained in PM10. These benefits can be achieved with no changes in boiler hardware and with a relatively small amount of tradeoffs: a 30% increase in PM10 mass emission and a 9-16% increase in fuel cost.

Compositional characteristics of the Fire Clay coal bed in a portion of eastern Kentucky

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hower, J.C.; Andrews, W.M. Jr.; Rimmer, S.M.

The Fire Clay (Hazard No. 4) coal bed (Middle Pennsylvanian Breathitt Formation) is one of the most extensively mined coal in eastern Kentucky. The coal is used for metallurgical and steam end uses and, with its low sulfur content, should continue to be a prime steam coal. This study focuses on the petrology, mineralogy, ash geochemistry, and palynology of the coal in an eight 7.5-min quadrangle area of Leslie, Perry, Knott, and Letcher counties.

Effect of nutrients on Chlorella pyrenoidosa for treatment of phenolic effluent of coal gasification plant.

PubMed

Stephen, Dayana Priyadharshini; Ayalur, Bakthavatsalam Kannappan

2017-05-01

The ability of Chlorella pyrenoidosa, a freshwater microalga, to degrade phenolic effluent of coal-based producer gas plant under ambient conditions was investigated. C. pyrenoidosa was able to grow in high-strength phenolic effluent. Major contaminant present in the effluent was phenol (C 6 H 5 OH). The effluent has 1475.3 ± 68 mg/L of initial total phenolic concentration. The effect of nutrients used for algal cultivation in phenol degradation was analyzed by inoculating four different concentrations, viz.,1, 2, 3, and 4 g of wet biomass/L of raw effluent of C. pyrenoidosa mixed with effluent into two batches (with and without nutrients). C. pyrenoidosa was able to degrade more than 95% of the phenol (C 6 H 5 OH) concentration with the algal concentrations of 3 and 4 g/L when supplemented with nutrients. With effluent devoid of nutrients, the average percent reduction in total phenolic compounds was observed to a maximum of 46%. No physical changes in the C. pyrenoidosa were observed during degradation. C. pyrenoidosa was able to consume the organic carbon present in the phenolic compounds as carbon source for its growth despite the inorganic carbon supplemented externally.

From in situ coal to the final coal product: A case study of the Danville Coal Member (Indiana)

USGS Publications Warehouse

Mastalerz, Maria; Padgett, P.L.

1999-01-01

A surface coal mine operation and preparation plant in southwestern Indiana was sampled to examine variations in coal quality and coal petrography parameters for the Danville Coal Member of the Dugger Formation (Pennsylvanian-Desmoinesian, Westphalian D). Representative samples from in situ coal, preparation plant feeds, and a final coal product were collected in order to compare coal quality, coal petrography, trace element concentrations, and ash chemistry of the coal to those of the product. Coal quality parameters of the in situ samples and various feeds, coarse refuse, and final product were variable. The quality of the final coal product was best predicted by the coal quality of the clean coal feed (from the middle portions of the seam). Some trace element contents, especially lead and arsenic, varied between the coal feeds and the product. Lead contents increased in the feeds and product compared to the channel sample of the raw coal, possibly due to contamination in the handling process.A surface coal mine operation and preparation plant in southwestern Indiana was sampled to examine variations in coal quality and coal petrography parameters for the Danville Coal Member of the Dugger Formation (Pennsylvanian-Desmoinesian, Westphalian D). Representative samples from in situ coal, preparation plant feeds, and a final coal product were collected in order to compare coal quality, coal petrography, trace element concentrations, and ash chemistry of the coal to those of the product. Coal quality parameters of the in situ samples and various feeds, coarse refuse, and final product were variable. The quality of the final coal product was best predicted by the coal quality of the clean coal feed (from the middle portions of the seam). Some trace element contents, especially lead and arsenic, varied between the coal feeds and the product. Lead contents increased in the feeds and product compared to the channel sample of the raw coal, possibly due to contamination in the handling process.

Self-Scrubbing Coal -- an integrated approach to clean air

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harrison, K.E.

1997-12-31

Carefree Coal is coal cleaned in a proprietary dense-media cyclone circuit, using ultrafine magnetite slurries, to remove noncombustible material, including up to 90% of the pyritic sulfur. Deep cleaning alone, however, cannot produce a compliance fuel from coals with high organic sulfur contents. In these cases, Self-Scrubbing Coal will be produced. Self-Scrubbing Coal is produced in the same manner as Carefree Coal except that the finest fraction of product from the cleaning circuit is mixed with limestone-based additives and briquetted. The reduced ash content of the deeply-cleaned coal will permit the addition of relatively large amounts of sorbent without exceedingmore » boiler ash specifications or overloading electrostatic precipitators. This additive reacts with sulfur dioxide (SO{sub 2}) during combustion of the coal to remove most of the remaining sulfur. Overall, sulfur reductions in the range of 80--90% are achieved. After nearly 5 years of research and development of a proprietary coal cleaning technology coupled with pilot-scale validation studies of this technology and pilot-scale combustion testing of Self-Scrubbing Coal, Custom Coals Corporation organized a team of experts to prepare a proposal in response to DOE`s Round IV Program Opportunity Notice for its Clean Coal Technology Program under Public Law 101-121 and Public Law 101-512. The main objective of the demonstration project is the production of a coal fuel that will result in up to 90% reduction in sulfur emissions from coal-fired boilers at a cost competitive advantage over other technologies designed to accomplish the same sulfur emissions and over naturally occurring low sulfur coals.« less

Environmental impacts of coal mine and thermal power plant to the surroundings of Barapukuria, Dinajpur, Bangladesh.

PubMed

Hossain, Md Nazir; Paul, Shitangsu Kumar; Hasan, Md Muyeed

2015-04-01

The study was carried out to analyse the environmental impacts of coal mine and coal-based thermal power plant to the surrounding environment of Barapukuria, Dinajpur. The analyses of coal, water, soil and fly ash were carried out using standard sample testing methods. This study found that coal mining industry and coal-based thermal power plant have brought some environmental and socio-economic challenges to the adjacent areas such as soil, water and air pollution, subsidence of agricultural land and livelihood insecurity of inhabitants. The pH values, heavy metal, organic carbon and exchangeable cations of coal water treated in the farmland soil suggest that coal mining deteriorated the surrounding water and soil quality. The SO4(2-) concentration in water samples was beyond the range of World Health Organisation standard. Some physico-chemical properties such as pH, conductivity, moisture content, bulk density, unburned carbon content, specific gravity, water holding capacity, liquid and plastic limit were investigated on coal fly ash of Barapukuria thermal power plant. Air quality data provided by the Barapukuria Coal Mining Company Limited were contradictory with the result of interview with the miners and local inhabitants. However, coal potentially contributes to the development of economy of Bangladesh but coal mining deteriorates the environment by polluting air, water and soil. In general, this study includes comprehensive baseline data for decision makers to evaluate the feasibility of coal power industry at Barapukuria and the coalmine itself.

PLANNING STUDY TO MODEL AND MONITOR COAL PILE RUNOFF. PHASE I

EPA Science Inventory

The report describes a planning study for predicting and monitoring the hydrologic and chemical characteristics of effluent streams resulting from precipitation impacting on open storage of coal. It includes: a survey of utilities on storage habits and treatment systems for coal ...

Low-rank coal oil agglomeration product and process

DOEpatents

Knudson, Curtis L.; Timpe, Ronald C.; Potas, Todd A.; DeWall, Raymond A.; Musich, Mark A.

1992-01-01

A selectively-sized, raw, low-rank coal is processed to produce a low ash and relative water-free agglomerate with an enhanced heating value and a hardness sufficient to produce a non-decrepitating, shippable fuel. The low-rank coal is treated, under high shear conditions, in the first stage to cause ash reduction and subsequent surface modification which is necessary to facilitate agglomerate formation. In the second stage the treated low-rank coal is contacted with bridging and binding oils under low shear conditions to produce agglomerates of selected size. The bridging and binding oils may be coal or petroleum derived. The process incorporates a thermal deoiling step whereby the bridging oil may be completely or partially recovered from the agglomerate; whereas, partial recovery of the bridging oil functions to leave as an agglomerate binder, the heavy constituents of the bridging oil. The recovered oil is suitable for recycling to the agglomeration step or can serve as a value-added product.

Low-rank coal oil agglomeration product and process

DOEpatents

Knudson, C.L.; Timpe, R.C.; Potas, T.A.; DeWall, R.A.; Musich, M.A.

1992-11-10

A selectively-sized, raw, low-rank coal is processed to produce a low ash and relative water-free agglomerate with an enhanced heating value and a hardness sufficient to produce a non-degradable, shippable fuel. The low-rank coal is treated, under high shear conditions, in the first stage to cause ash reduction and subsequent surface modification which is necessary to facilitate agglomerate formation. In the second stage the treated low-rank coal is contacted with bridging and binding oils under low shear conditions to produce agglomerates of selected size. The bridging and binding oils may be coal or petroleum derived. The process incorporates a thermal deoiling step whereby the bridging oil may be completely or partially recovered from the agglomerate; whereas, partial recovery of the bridging oil functions to leave as an agglomerate binder, the heavy constituents of the bridging oil. The recovered oil is suitable for recycling to the agglomeration step or can serve as a value-added product.

Dual inoculation with an Aarbuscular Mycorrhizal fungus and Rhizobium to facilitate the growth of alfalfa on coal mine substrates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, F.Y.; Bi, Y.L.; Wong, M.H.

2009-07-01

A pot experiment was conducted to investigate the effects of Glomus mosseae and Rhizobium on Medicago sativa grown on three types of coal mine substrates, namely a mixture of coal wastes and sands (CS), coal wastes and fly ash (CF), and fly ash (FA). Inoculation with Rhizobium alone did not result in any growth response but G. mosseae alone displayed a significant effect on plant growth. G. mosseae markedly increased the survival rate of M. sativa in CS substrate. In CF and FA substrates the respective oven dry weights of M. sativa inoculated with G. mosseae were 1.8 and 5.1more » times higher than those without inoculation. Based on nitrogen (N), phosphorus (P) and potassium (K) uptake and legume growth, the results also show that dual inoculation in CS and CF substrates elicited a synergistic effect. This indicates that inoculation with arbuscular mycorrhizal (AM) fungi may be a promising approach for revegetation of coal mine substrates.« less

Life cycle assessment of sewage sludge co-incineration in a coal-based power station.

PubMed

Hong, Jingmin; Xu, Changqing; Hong, Jinglan; Tan, Xianfeng; Chen, Wei

2013-09-01

A life cycle assessment was conducted to evaluate the environmental and economic effects of sewage sludge co-incineration in a coal-fired power plant. The general approach employed by a coal-fired power plant was also assessed as control. Sewage sludge co-incineration technology causes greater environmental burden than does coal-based energy production technology because of the additional electricity consumption and wastewater treatment required for the pretreatment of sewage sludge, direct emissions from sludge incineration, and incinerated ash disposal processes. However, sewage sludge co-incineration presents higher economic benefits because of electricity subsidies and the income generating potential of sludge. Environmental assessment results indicate that sewage sludge co-incineration is unsuitable for mitigating the increasing pressure brought on by sewage sludge pollution. Reducing the overall environmental effect of sludge co-incineration power stations necessitates increasing net coal consumption efficiency, incinerated ash reuse rate, dedust system efficiency, and sludge water content rate. Copyright © 2013 Elsevier Ltd. All rights reserved.

Improved Supercritical-Solvent Extraction of Coal

NASA Technical Reports Server (NTRS)

Compton, L.

1982-01-01

Raw coal upgraded by supercritical-solvent extraction system that uses two materials instead of one. System achieved extraction yields of 20 to 49 weight percent. Single-solvent yields are about 25 weight percent. Experimental results show extraction yields may be timedependent. Observed decreases in weight of coal agreed well with increases in ash content of residue.

Characterization of Coal Combustion Residues from Electric Utilities Using Wet Scrubbers for Multi-Pollutant Control

EPA Science Inventory

This report evaluates changes that may occur to coal combustion residues (CCRs) in response to changes in air pollution control technology at coal-fired power plants, which will reduce emissions from the flue gas stack by transferring pollutants to fly ash and other air pollution...

Coal liquefaction process

DOEpatents

Carr, Norman L.; Moon, William G.; Prudich, Michael E.

1983-01-01

A C.sub.5 -900.degree. F. (C.sub.5 -482.degree. C.) liquid yield greater than 50 weight percent MAF feed coal is obtained in a coal liquefaction process wherein a selected combination of higher hydrogen partial pressure, longer slurry residence time and increased recycle ash content of the feed slurry are controlled within defined ranges.

Co-combustion of bituminous coal and biomass fuel blends: Thermochemical characterization, potential utilization and environmental advantage.

PubMed

Zhou, Chuncai; Liu, Guijian; Wang, Xudong; Qi, Cuicui

2016-10-01

The thermochemical characteristics and gaseous trace pollutant behaviors during co-combustion medium-to-low ash bituminous coal with typical biomass residues (corn stalk and sawdust) were investigated. Lowering of ignition index, burnout temperature and activation energy in the major combustion stage are observed in the coal/biomass blends. The blending proportion of 20% and 30% are regarded as the optimum blends for corn stalk and sawdust, respectively, in according the limitations of heating value, activation energy, flame stability and base/acid ratio. The reductions of gaseous As, Cd, Cu, Pb, Zn and polycyclic aromatic hydrocarbon (PAHs) were 4.5%, 7.8%, 6.3%, 9.8%, 9.4% and 17.4%, respectively, when co-combustion coal with 20% corn stalk. The elevated capture of trace elements were found in coal/corn stalk blend, while the coal/sawdust blend has the better PAHs control potential. The reduction mechanisms of gaseous trace pollutants were attributed to the fuel property, ash composition and relative residence time during combustion. Copyright © 2016 Elsevier Ltd. All rights reserved.

Investigation of flow behaviour of coal particles in a pilot-scale fluidized bed gasifier (FBG) using radiotracer technique.

PubMed

Pant, H J; Sharma, V K; Kamudu, M Vidya; Prakash, S G; Krishanamoorthy, S; Anandam, G; Rao, P Seshubabu; Ramani, N V S; Singh, Gursharan; Sonde, R R

2009-09-01

Knowledge of residence time distribution (RTD), mean residence time (MRT) and degree of axial mixing of solid phase is required for efficient operation of coal gasification process. Radiotracer technique was used to measure the RTD of coal particles in a pilot-scale fluidized bed gasifier (FBG). Two different radiotracers i.e. lanthanum-140 and gold-198 labeled coal particles (100 gm) were independently used as radiotracers. The radiotracer was instantaneously injected into the coal feed line and monitored at the ash extraction line at the bottom and gas outlet at the top of the gasifier using collimated scintillation detectors. The measured RTD data were treated and MRTs of coal/ash particles were determined. The treated data were simulated using tanks-in-series model. The simulation of RTD data indicated good degree of mixing with small fraction of the feed material bypassing/short-circuiting from the bottom of the gasifier. The results of the investigation were found useful for optimizing the design and operation of the FBG, and scale-up of the gasification process.

78 FR 18629 - Notice of Lodging of Proposed Consent Decree Under the Clean Water Act

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-27

... ash discharges after BADGER's 2014 operating system, perform other injunctive relief, and pay a $25... with the defendant's discharge of ash from BADGER, a coal- fired, stream-driven ferry that operates...

40 CFR 434.23 - Effluent limitations guidelines representing the degree of effluent reduction attainable by...

Code of Federal Regulations, 2013 CFR

2013-07-01

... economically achievable (BAT). 434.23 Section 434.23 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) COAL MINING POINT SOURCE CATEGORY BPT, BAT, BCT... by application of the best available technology economically achievable (BAT). (a) Except as provided...

40 CFR 434.23 - Effluent limitations guidelines representing the degree of effluent reduction attainable by...

Code of Federal Regulations, 2014 CFR

2014-07-01

... economically achievable (BAT). 434.23 Section 434.23 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) COAL MINING POINT SOURCE CATEGORY BPT, BAT, BCT... by application of the best available technology economically achievable (BAT). (a) Except as provided...

40 CFR 434.53 - Effluent limitations guidelines representing the degree of effluent reduction attainable by...

Code of Federal Regulations, 2013 CFR

2013-07-01

... economically achievable (BAT). 434.53 Section 434.53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) COAL MINING POINT SOURCE CATEGORY BPT, BAT, BCT... economically achievable (BAT). (a) Reclamation areas. The limitations of this subsection apply to discharges...

40 CFR 434.74 - Effluent limitations attainable by application of the best conventional pollutant control...

Code of Federal Regulations, 2010 CFR

2010-07-01

... application of the best conventional pollutant control technology (BCT). 434.74 Section 434.74 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS COAL MINING POINT... Effluent limitations attainable by application of the best conventional pollutant control technology (BCT...

Removal of Procion Red dye from colored effluents using H2SO4-/HNO3-treated avocado shells (Persea americana) as adsorbent.

PubMed

Georgin, Jordana; da Silva Marques, Bianca; da Silveira Salla, Julia; Foletto, Edson Luiz; Allasia, Daniel; Dotto, Guilherme Luiz

2018-03-01

The treatment of colored effluents containing Procion Red dye (PR) was investigated using H 2 SO 4 and HNO 3 modified avocado shells (Persea americana) as adsorbents. The adsorbent materials (AS-H 2 SO 4 and AS-HNO 3 ) were properly characterized. The adsorption study was carried out considering the effects of adsorbent dosage and pH. Kinetic, equilibrium, and thermodynamic aspects were also evaluated. Finally, the adsorbents were tested to treat simulated dye house effluents. For both materials, the adsorption was favored using 0.300 g L -1 of adsorbent at pH 6.5, where, more than 90% of PR was removed from the solution. General order model was able to explain the adsorption kinetics for both adsorbents. The Sips model was adequate to represent the isotherm data, being the maximum adsorption capacities of 167.0 and 212.6 mg g -1 for AS-H 2 SO 4 and AS-HNO 3 , respectively. The adsorption processes were thermodynamically spontaneous, favorable (- 17.0 < ΔG 0  < - 13.2 kJ mol -1 ), and exothermic (ΔH 0 values of - 29 and - 55 kJ mol -1 ). AS-H 2 SO 4 and AS-HNO 3 were adequate to treat dye house effluents, attaining color removal percentages of 82 and 75%. Avocado shells, after a simple acid treatment, can be a low-cost option to treat colored effluents.

POLISHING INDUSTRIAL WASTE STREAM EFFLUENTS USING FLY ASH - NATURAL CLAY SORBENT COMBINATION

EPA Science Inventory

A laboratory evaluation of the use of acidic and basic fly ashes, bentonite, bauxite, illite, kaolinite, zeolite, vermiculite, and activated alumina is presented for polishing a 3.8 x 10 to the 6th power liters per day waste stream from the feldspar mining and processing industry...

Characterization of coal fly ash components by laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Ctvrtnickova, Tereza; Mateo, Mari-Paz; Yañez, Armando; Nicolas, Gines

2009-10-01

The high sensitivity of laser-induced breakdown spectroscopy (LIBS) for the detection of most of the fly ash components enables the analysis of these residues produced during the combustion of coal. Fly ash consists of oxides (SiO 2, Al 2O 3, Fe 2O 3, CaO…) and unburnt carbon which is the major determinant of combustion efficiency in coal fired boilers. For example, an excessive amount of residual carbon dispersed in the fly ash means a significant loss of energy (Styszko et al., 2004 [1]). Standard methods employed for the analysis of fly ash make not possible a control of boiler in real time. LIBS technique can significantly reduce the time of analysis, in some cases even an online detection can be performed. For this reason, some studies have been addressed in order to demonstrate the capability of the laser-induced breakdown spectroscopy technique for the detection of carbon content in high pressure conditions typical of thermal power plants (Noda et al., 2002 [2]) and for the monitoring of unburnt carbon for the boiler control in real time (Kurihara et al., 2003 [3]). In particular, the content of unburnt carbon is a valuable indicator for the control of fly ash quality and for the boiler combustion. Depending on this unburnt carbon content, fly ash can be disposed as an industrial waste or as a raw material for the production of concrete in the construction sector. In this study, analyses were performed on specimens of various forms of preparation. Pressed pellets were prepared with two different binders. Presented results concern the nature and amount of the binder used to pelletize the powder, and the laser-induced breakdown spectroscopy parameters and procedure required to draw calibration curves of elements from the fly ash. Analysis "on tape" was performed in order to establish the experimental conditions for the future "online analysis".

Study of Natural Radioactivity in Coal Samples of Baganuur Coal Mine, Mongolia

NASA Astrophysics Data System (ADS)

Altangerel, M.; Norov, N.; Altangerel, D.

2009-03-01

Coal and soil samples from Baganuur Coal Mine (BCM) of Mongolia have been investigated. The activities of 226Ra, 232Th and 40K have been measured by gamma-ray spectrometry using shielded HPGe detector. Contents of natural radionuclide elements (U, Th and K) have been determined. Also the activities and contents of radionuclide of ashes were determined which generated in Thermal Power Plant ♯3 of Ulaanbaatar from coal supplied from BCM.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scott, A.N.; Thomas, M.D.A.

An investigation of fly ash (FA) produced from various blends of coal and petroleum coke (pet coke) fired at Belledune Generating Station, New Brunswick, Canada, was conducted to establish its performance relative to FA derived from coal-only combustion and its compliance with CSA A3000. The FA samples were beneficiated by an electrostatic separation process to produce samples for testing with a range of loss-on-ignition (LOI) values. The results of these studies indicate that the combustion of pet coke results in very little inorganic residue (for example, typically less than 0.5% ash) and the main impact on FA resulting from themore » co-combustion of coal and up to 25% pet coke is an increase in the unburned carbon content and LOI values. The testing of FA after beneficiation indicates that FA produced from fuels with up to 25% pet coke performs as good as FA produced from the same coal without pet coke.« less

Desulfurization of Coal in Fluidized Beds

NASA Technical Reports Server (NTRS)

Maddury, R.; Kalvinskas, J.

1985-01-01

Experimental dry chemical process for removing sulfur from coal-and thereby reducing harmful sulfur emissions from coal-fired electric powerplants-promises more economical and effective than older wet chemical processes. New process faster, requires smaller amounts of chemical reagents, and produces no liquid effluents, which poses disposal problem.

Energy recycling by co-combustion of coal and recovered paint solids from automobile paint operations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Achariya Suriyawong; Rogan Magee; Ken Peebles

2009-05-15

This paper presents the results of an experimental study of particulate emission and the fate of 13 trace elements (arsenic (As), barium (Ba), cadmium (Cd), chromium (Cr), copper (Cu), cobalt (Co), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), mercury (Hg), vanadium (V), and zinc (Zn)) during combustion tests of recovered paint solids (RPS) and coal. The emissions from combustions of coal or RPS alone were compared with those of co-combustion of RPS with subbituminous coal. The distribution/partitioning of these toxic elements between a coarse-mode ash (particle diameter (d{sub p}) > 0.5 {mu}m), a submicrometer-mode ash (d{sub p} < 0.5more » {mu}m), and flue gases was also evaluated. Submicrometer particles generated by combustion of RPS alone were lower in concentration and smaller in size than that from combustion of coal. However, co-combustion of RPS and coal increased the formation of submicrometer-sized particles because of the higher reducing environment in the vicinity of burning particles and the higher volatile chlorine species. Hg was completely volatilized in all cases; however, the fraction in the oxidized state increased with co-combustion. Most trace elements, except Zn, were retained in ash during combustion of RPS alone. Mo was mostly retained in all samples. The behavior of elements, except Mn and Mo, varied depending on the fuel samples. As, Ba, Cr, Co, Cu, and Pb were vaporized to a greater extent from cocombustion of RPS and coal than from combustion of either fuel. Evidence of the enrichment of certain toxic elements in submicrometer particles has also been observed for As, Cd, Cr, Cu, and Ni during co-combustion. 27 refs., 6 figs., 5 tabs.« less

Small, modular, low-cost coal-fired power plants for the international market

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zauderer, B.; Frain, B.; Borck, B.

1997-12-31

This paper presents recent operating results of Coal Tech`s second generation, air cooled, slagging coal combustor, and its application to power plants in the 1 to 20 MW range. This 20 MMBtu/hour combustor was installed in a new demonstration plant in Philadelphia, PA in 1995. It contains the combustion components of a 1 MWe coal fired power plant, a 17,500 lb/hour steam boiler, coal storage and feed components, and stack gas cleanup components. The plant`s design incorporates improvements resulting from 2,000 hours of testing between 1987 and 1993 on a first generation, commercial scale, air cooled combustor of equal thermalmore » rating. Since operations began in early 1996, a total of 51 days of testing have been successfully completed. Major results include durability of the combustor`s refractory wall, excellent combustion with high ash concentration in the fuel, removal of 95% to 100% of the slag in the combustor, very little ash deposition in the boiler, major reduction of in-plant parasitic power, and simplified power system control through the use of modular designs of sub-systems and computer control. Rapid fuel switching between oil, gas, and coal and turndown of up to a factor of three was accomplished. All these features have been incorporated in advanced coal fired plant designs in the 1 to 20 MWe range. Incremental capital costs are only $100 to $200/kW higher than comparable rated gas or oil fired steam generating systems. Most of its components and subsystems can be factory assembled for very rapid field installation. The low capital, low operating costs, fuel flexibility, and compatibility with very high ash fuels, make this power system very attractive in regions of the world having domestic supplies of these fuels.« less

Mercury emission and speciation of coal-fired power plants in China

NASA Astrophysics Data System (ADS)

Wang, S. X.; Zhang, L.; Li, G. H.; Wu, Y.; Hao, J. M.; Pirrone, N.; Sprovieri, F.; Ancora, M. P.

2010-02-01

Comprehensive field measurements are needed to understand the mercury emissions from Chinese power plants and to improve the accuracy of emission inventories. Characterization of mercury emissions and their behavior were measured in six typical coal-fired power plants in China. During the tests, the flue gas was sampled simultaneously at inlet and outlet of Selective Catalytic Reduction (SCR), electrostatic precipitators (ESP), and flue gas desulfurization (FGD) using the Ontario Hydro Method (OHM). The pulverized coal, bottom ash, fly ash and gypsum were also sampled in the field. Mercury concentrations in coal burned in the measured power plants ranged from 17 to 385 μg/kg. The mercury mass balances for the six power plants varied from 87 to 116% of the input coal mercury for the whole system. The total mercury concentrations in the flue gas from boilers were at the range of 1.92-27.15 μg/m3, which were significantly related to the mercury contents in burned coal. The mercury speciation in flue gas right after the boiler is influenced by the contents of halogen, mercury, and ash in the burned coal. The average mercury removal efficiencies of ESP, ESP plus wet FGD, and ESP plus dry FGD-FF systems were 24%, 73% and 66%, respectively, which were similar to the average removal efficiencies of pollution control device systems in other countries such as US, Japan and South Korea. The SCR system oxidized 16% elemental mercury and reduced about 32% of total mercury. Elemental mercury, accounting for 66-94% of total mercury, was the dominant species emitted to the atmosphere. The mercury emission factor was also calculated for each power plant.

Mercury emission and speciation of coal-fired power plants in China

NASA Astrophysics Data System (ADS)

Wang, S.; Zhang, L.; Li, G.; Wu, Y.; Hao, J.; Pirrone, N.; Sprovieri, F.; Ancora, M. P.

2009-11-01

Comprehensive field measurements are needed to understand the mercury emissions from Chinese power plants and to improve the accuracy of emission inventories. Characterization of mercury emissions and their behavior were measured in six typical coal-fired power plants in China. During the tests, the flue gas was sampled simultaneously at inlet and outlet of selective catalyst reduction (SCR), electrostatic precipitators (ESP), and flue gas desulfurization (FGD) using the Ontario Hydro Method (OHM). The pulverized coal, bottom ash, fly ash and gypsum were also sampled in the field. Mercury concentrations in coal burned in the measured power plants ranged from 17 to 385 μg/kg. The mercury mass balances for the six power plants varied from 87 to 116% of the input coal mercury for the whole system. The total mercury concentrations in the flue gas from boilers were at the range of 1.92-27.15 μg/m3, which were significantly related to the mercury contents in burned coal. The mercury speciation in flue gas right after the boiler is influenced by the contents of halogen, mercury, and ash in the burned coal. The average mercury removal efficiencies of ESP, ESP plus wet FGD, and ESP plus dry FGD-FF systems were 24%, 73% and 66%, respectively, which were similar to the average removal efficiencies of pollution control device systems in other countries such as US, Japan and South Korea. The SCR system oxidized 16% elemental mercury and reduced about 32% of total mercury. Elemental mercury, accounting for 66-94% of total mercury, was the dominant species emitted to the atmosphere. The mercury emission factor was also calculated for each power plant.

Direct liquefaction Proof-of-Concept facility. Final technical progress report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Comolli, A.G.; Lee, L.K.; Pradhan, V.R.

1995-08-01

This report presents the results of work which included extensive modifications to HRI`s existing 3 ton per day Process Development Unit (PDU) and completion of the first PDU run. The 58-day Run 1 demonstrated scale-up of the Catalytic Two-Stage Liquefaction (CTSL Process) on Illinois No. 6 coal to produce distillate liquid products at a rate of up to 5 barrels per to of moisture-ash-free coal. The Kerr McGee Rose-SR unit from Wilsonville was redesigned and installed next to the US Filter installation to allow a comparison of the two solids removal systems. Also included was a new enclosed reactor tower,more » upgraded computer controls and a data acquisition system, an alternate power supply, a newly refurbished reactor, an in-line hydrotreater, interstage sampling system, coal handling unit, a new ebullating pump, load cells and improved controls and remodeled preheaters. Distillate liquid yields of 5 barrels/ton of moisture ash free coal were achieved. Coal slurry recycle rates were reduced from the 2--2.5 to 1 ratio demonstrated at Wilsonville to as low as 0.9 to 1. Coal feed rates were increased during the test by 50% while maintaining process performance at a marginally higher reactor severity. Sulfur in the coal was reduced from 4 wt% to ca. 0.02 wt% sulfur in the clean distillate fuel product. More than 3,500 gallons of distillate fuels were collected for evaluation and upgrading studies. The ROSE-SR Process was operated for the first time with a pentane solvent in a steady-state model. The energy rejection of the ash concentrate was consistently below prior data, being as low as 12%, allowing improved liquid yields and recovery.« less

Remedial investigation report on Chestnut Ridge Operable Unit 2 (filled coal ash pond/Upper McCoy Branch) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. Volume 2: Appendixes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1994-08-01

This report comprises appendices A--J which support the Y-12 Plant`s remedial action report involving Chestnut Ridge Operable Unit 2 (filled coal ash pond/Upper McCoy Branch). The appendices cover the following: Sampling fish from McCoy Branch; well and piezometer logs; ecological effects of contaminants in McCoy Branch 1989-1990; heavy metal bioaccumulation data; microbes in polluted sediments; and baseline human health risk assessment data.

Formulation of low solids coal water slurry from advanced coal cleaning waste fines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Battista, J.J.; Morrison, J.L.; Lambert, A.

1997-07-01

GPU Genco, the New York State Electric and Gas Corporation (NYSEG), Penn State University and the Homer City Coal Processing Corporation are conducting characterization and formulation tests to determine the suitability of using minus 325 mesh coal waste fines as a low solids coal water slurry (CWS) co-firing fuel. The fine coal is contained in a centrifuge effluent stream at the recently modified Homer City Coal Preparation Plant. Recovering, thickening and then co-firing this material with pulverized coal is one means of alleviating a disposal problem and increasing the Btu recovery for the adjacent power plant. The project team ismore » currently proceeding with the design of a pilot scale system to formulate the effluent into a satisfactory co-firing fuel on a continuous basis for combustion testing at Seward Station. The ultimate goal is to burn the fuel at the pulverized coal units at the Homer City Generating Station. This paper presents the success to date of the slurry characterization and pilot scale design work. In addition, the paper will update GPU Genco`s current status for the low solids coal water slurry co-firing technology and will outline the company`s future plans for the technology.« less

Using simulated maps to interpret the geochemistry, formation and quality of the Blue Gem Coal Bed, Kentucky, USA

USGS Publications Warehouse

Geboy, Nicholas J.; Olea, Ricardo A.; Engle, Mark A.; Martin-Fernandez, Jose Antonio

2013-01-01

This study presents geostatistical simulations of coal-quality parameters, major oxides and trace metals for an area covering roughly 812 km2 of the Blue Gem coal bed in southeastern Kentucky, USA. The Blue Gem, characterized by low ash yield and low sulfur content, is an important economic resource. Past studies have characterized the Blue Gem's geochemistry, palynology and petrography and inferred a depositional setting of a planar peat deposit that transitioned to slightly domed later in its development. These studies have focused primarily on vertical geochemical trends within the coal bed. Simulated maps of chemical elements derived from 45 measured sample locations across the study area provide an opportunity to observe changes in the horizontal direction within the coal bed. As the Blue Gem coal bed shows significant vertical chemical trends, care was taken in this study to try to select samples from a single, middle portion of the coal. By revealing spatial distribution patterns of elements across the middle of the bed, associations between different components of the coal can be seen. The maps therefore help to provide a picture of the coal-forming peat bog at an instant in geologic time and allow interpretation of a depositional setting in the horizontal direction. Results from this middle portion of the coal suggest an association of SiO2 with both K2O and TiO2 in different parts of the study area. Further, a pocket in the southeast of the study area shows elevated concentrations of elements attributable to observed carbonate-phase minerals (MgO, CaO, Ba and Sr) as well as elements commonly associated with sulfide-phase minerals (Cu, Mo and Ni). Areas of relatively high ash yield are observed in the north and south of the mapped area, in contrast to the low ash yields seen towards the east. Additionally, we present joint probability maps where multiple coal-quality parameters are plotted simultaneously on one figure. This application allows researchers to investigate associations of more than two components in a straight-forward manner useful in guiding resource exploration.

Fuel Characterization of Newly Discovered Nigerian Coals

NASA Astrophysics Data System (ADS)

Bevan Nyakuma, Bemgba; Oladokun, Olagoke; Jauro, Aliyu; Damian Nyakuma, Denen

2017-07-01

This study seeks to characterize and highlight the fuel properties, rank, and classification of coals from Ihioma (IHM) and Ogboligbo (OGB) in Imo and Kogi states of Nigeria, respectively. The fuel properties were examined based on ultimate, proximate, and bomb calorific analyses. The results indicated that IHM coal contains comparatively higher C and H but lower O, N, and S content than OGB. In addition, the nitrogen (N) and sulphur (S) content for both coal samples were above 0.7 wt.% and 1.5 wt.%, respectively, which indicates high potential for pollutant emissions. Furthermore, the coal proximate properties were below 5 wt.% for Moisture; Volatiles (70 wt.%); Fixed Carbon (45 wt.%) and Ash (2.5 wt.%) on average. IHM coal has an HHV of 19.40 MJ/kg whereas OGB is 15.55 MJ/kg. This is due to the low carbon (C), hydrogen (H) and high oxygen (O) content in OGB whereas IHM contains higher VM and HHV. Furthermore, OGB presents better handling, storage, and transport potential. Furthermore, OGB has a higher fuel ratio and value index due to lower moisture, ash content, and volatiles. Based on the ASTM D388 standard, the coals were classified as Lignite (Brown) Low-Rank Coals (LRCs) with potential for energy recovery.

Production of a bioflocculant from Pseudomonas veronii L918 using the hydrolyzate of peanut hull and its application in the treatment of ash-flushing wastewater generated from coal fired power plant.

PubMed

Liu, Weijie; Hao, Yan; Jiang, Jihong; Zhu, Aihua; Zhu, Jingrong; Dong, Zhen

2016-10-01

In this study, bioflocculant produced by Pseudomonas veronii L918 was applied to treat ash-flushing wastewater. The strain L918 could convert the hydrolyzate of peanut hull into bioflocculant, which can effectively reduce the production cost of bioflocculant. The yield of 3.39g/L bioflocculant MBF-L918 was achieved when 300mL/L peanut hull hydrolyzate was used as carbon source. The bioflocculant MBF-L918 contains 77.14% polysaccharides and 4.84% proteins, and the molecular weight (MW) of MBF-L918 is 24.77kDa. Furthermore, MBF-L918 showed good flocculating efficiency of 92.51% to ash-flushing wastewater when 2.83mg/L MBF-L918 was added, and thus achieved the recycling of ash-flushing wastewater. This study reported for the first time that the bioflocculant was produced using peanut hull hydrolyzate and effectively applied in the treatment of coal ash-flushing wastewater. Copyright © 2016 Elsevier Ltd. All rights reserved.

Flotation of oil-agglomerated coal for ash and pyrite removal -- Simultaneous grinding and agglomeration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, S.; Perkson, A.; Trass, O.

1996-12-31

Oil agglomeration is an excellent technique for the beneficiation of fine coal. For separation of the spherical agglomerates by screening, a high level of oil must be used, however. When the subsequent separation is done by flotation, this disadvantage is eliminated. Better pyrite removal is also possible. In this paper, such a fine coal beneficiation process, also called hydrophobic flocculation-flotation (HFF), is described. It features low non-polar oil consumption, intensive mechanical energy input, and smaller agglomerates or looser flocs. This process can be simplified by grinding the coal in water with small amounts of oil added. The excess grinding energymore » is then used for agglomerating the coal. The Prince coal from Nova Scotia contained 13.3% ash and 3.3% total sulfur, 1.4% pyritic. After four stages of flotation, ash and pyrite removal were 93% and 66% respectively, with 87% combustibles recovery. The parameters affecting the HFF process, such as particle size, dosage of non-polar oil, pH value of the slurry and duration of agitation, were investigated. Simultaneous grinding and agglomeration (SGA) utilizing the Szego Mill was also explored at the very low oil levels used. The intensive agitation/preconditioning step prior to flotation was eliminated. When the other parameters established from the sequential process were used with the SGA process, virtually identical beneficiation results were obtained, but with slightly lower combustibles recovery. While further testing is required to properly optimize the SGA process conditions, significant equipment simplification and energy savings are possible.« less

Distinctive features of high-ash bituminuos coals combution with low milling fineness in furnace chambers with bottom blowing

NASA Astrophysics Data System (ADS)

Zroychikov, N. A.; Kaverin, A. A.; Biryukov, Ya A.

2017-11-01

Nowadays the problem of improvement of pulverized coal combustion schemes is an actual one for national power engineering, especially for combustion of coals with low milling fineness with significant portion of moisture or mineral impurities. In this case a big portion of inert material in the fuel may cause impairment of its ignition and combustion. In addition there are a lot of boiler installations on which nitrogen oxides emission exceeds standard values significantly. Decreasing of milling fineness is not without interest as a way of lowering an electric energy consumption for pulverization, which can reach 30% of power plant’s auxiliary consumption of electricity. Development of a combustion scheme meeting the requirements both for effective coal burning and environmental measures (related to NOx emission) is a complex task and demands compromising between these two factors, because implementation of NOx control by combustion very often leads to rising of carbon-in-ash loss. However widespread occurrence of such modern research technique as computer modeling allows to conduct big amount of variants calculations of combustion schemes with low cost and find an optimum. This paper presents results of numerical research of combined schemes of coal combustion with high portion of inert material based on straight-flow burners and nozzles. Several distinctive features of furnace aerodynamics, heat transfer and combustion has been found. The combined scheme of high-ash bituminouos coals combustion with low milling fineness, which allows effective combustion of pointed type of fuels with nitrogen oxides emission reduction has been proposed.

Evaluation of interactions between soil and coal fly ash leachates using column percolation tests.

PubMed

Tsiridis, V; Petala, M; Samaras, P; Sakellaropoulos, G P

2015-09-01

The aim of this work was the assessment of the environmental impact of different origin fly ashes with regard to their final disposal. The experimental procedure included the performance of single column tests and column tests of fly ash and soil in series. The appraisal of the potential environmental hazards was implemented using physicochemical analyses and bioassays. Two different fly ash samples were examined, one fly ash produced from the combustion of sub-bituminous coal (CFA) and one fly ash produced from the combustion of lignite (LFA). Single column percolation tests were performed according to NEN 7343 protocol, while fly ash/soil experiments were conducted incorporating slight modifications to this protocol. The study focused on the release of metals Ba, Cr, Cu, Mo, Se and Zn and the ecotoxic behavior of leachates on crustacean Daphnia magna and bacteria Vibrio fischeri. The infiltration of the leachates of both fly ashes through soil affected considerably their leaching profile. The transport of Cu and Zn was facilitated by the dynamic leaching conditions and influenced by the pH of the leachates. Moreover, the release and bioavailability of Cr, Cu and Zn was probably altered during the infiltration experiments and organisms' response was not always correlated with the concentration of metals. Nevertheless, the results are signalling that possible manipulations and final disposal of fly ash should be considered when environmental threats are investigated. Copyright © 2015 Elsevier Ltd. All rights reserved.

Controlled short residence time coal liquefaction process

DOEpatents

Anderson, Raymond P.; Schmalzer, David K.; Wright, Charles H.

1982-05-04

Normally solid dissolved coal product and a distillate liquid product are produced by continuously passing a feed slurry comprising raw feed coal and a recycle solvent oil and/or slurry together with hydrogen to a preheating-reaction zone (26, alone, or 26 together with 42), the hydrogen pressure in the preheating-reaction zone being at least 1500 psig (105 kg/cm.sup.2), reacting the slurry in the preheating-reaction zone (26, or 26 with 42) at a temperature in the range of between about 455.degree. and about 500.degree. C. to dissolve the coal to form normally liquid coal and normally solid dissolved coal. A total slurry residence time is maintained in the reaction zone ranging from a finite value from about 0 to about 0.2 hour, and reaction effluent is continuously and directly contacted with a quenching fluid (40, 68) to substantially immediately reduce the temperature of the reaction effluent to below 425.degree. C. to substantially inhibit polymerization so that the yield of insoluble organic matter comprises less than 9 weight percent of said feed coal on a moisture-free basis. The reaction is performed under conditions of temperature, hydrogen pressure and residence time such that the quantity of distillate liquid boiling within the range C.sub.5 -455.degree. C. is an amount at least equal to that obtainable by performing the process under the same conditions except for a longer total slurry residence time, e.g., 0.3 hour. Solvent boiling range liquid is separated from the reaction effluent and recycled as process solvent.

The Next Generation of leaching Tests

EPA Science Inventory

Coal ash and other industrial by-products are used in building, construction, engineering and even agricultural applications. Changes in multi-pollutant control technology at coal-fired power plants and other combustion sources are shifting mercury (Hg) and other constituents of...

Trace element geochemistry of altered volcanic ash layers (tonsteins) in late Permian coal-bearing formations of eastern Yunnan and western Guizhou Provinces, China

USGS Publications Warehouse

Zhou, Y.; Bohor, B.F.; Ren, Y.

2000-01-01

Trace element compositions were determined (by instrumental neutron activation analysis; INAA) in 30 samples of synsedimentary volcanic ash-derived tonsteins and detrital claystones from coal seams within the late Permian coal-bearing formation of eastern Yunnan and western Guizhou Provinces, China. The characteristics of trace-element geochemistry in the tonsteins can be distinguished from those of detrital claystones because of the former's unique volcanic-ash origin. The detrital claystones are characterized by their relatively high content of V, Ti, Sc, Cr, Co and Ni, relatively low content of Th and U, Th/U ratio, and small negative Eu anomaly (Eu/Eu* 0.63-0.93). Overall, these trace element characteristics are consistent with a mafic source similar to the composition of basalt rocks in the erosional region on the western edge of the study area. In contrast, the tonsteins are low in V, Ti, Sc, Cr, Co and Ni contents and have a high Th/U ratio with a distinct negative Eu anomaly (Eu/Eu* normally in the range of 0.2-0.4), consistent with a silicic magmatic source. Within the group of tonsteins, those from the lower section (P2.1) of the coal-bearing formation are relatively high in Ti, Zr, Hf, Nb, Ta and rare earth elements (REE), as compared to those from the middle and upper sections (P2.2+3). In trace-element discrimination diagrams (scatter plots) of Hf-Ta, Ti-Ta, Ti-V, Hf-Sc, Lu-Hf and Lu-Th, tonsteins from the P2.1 horizon always fall in isolated distribution areas, separate from the tonsteins of the P2.2+3 horizon. These results suggest that the source materials of tonsteins from the two separate horizons were probably derived from volcanic ash falls of two distinctly different natures. Based on a comparison of the concentrations and assemblages of trace elements between various magmatic rocks, the source materials of tonsteins from P2.1 horizon were mostly composed of calc-alkalic, silica-poor volcanic ash (similar to rhyodacitic magma), whereas those from P2.+3 were apparently more siliceous and K-rich (rhyolitic magma). Thus, tonsteins from the two different horizons are characterized by unique geochemical properties, which remain constant over a wide lateral extent. Integration of trace-elemental compositions with mineralogical and textural observations makes possible the establishment of tonstein stratigraphy, thus, facilitating more precise and reliable coal-seam correlations. (C) 2000 Elsevier Science B.V. All rights reserved.Trace element compositions were determined in 30 samples of synsedimentary volcanic ash-derived tonsteins and detrital claystones from coal seams within the late Permian coal-bearing formation of eastern Yunnan and western Guizhou Provinces, China. The characteristics of trace-element geochemistry in the tonsteins can be distinguished from those of detrital claystones because of the former's unique volcanic-ash origin. The detrital claystones are characterized by their relatively high content of V, Ti, Sc, CR, Co and Ni, relatively low content of Th and U, Th/U ratio, and small negative Eu anomaly.

Colorado Springs dedicates zero-discharge coal plant. [Ray D. Nixon plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hennessy, M.; Zeien, C.T.

1980-12-01

The zero-discharge Ray D. Nixon coal-fired power plant was designed to treat and recycle effluents in a region with limited water supplies. The site purchase included groundwater rights and some diversion rights, but a properly-managed local aquifer was determined to be adequate. The closed-loop design recovers 95 percent of the water for reuse. The overall water-management system produces adequate water and treats effluents at less cost and with higher water-quality protection than alternate systems. (DCK)

Leaching behavior of coal combustion products and the environmental implication in road construction.

DOT National Transportation Integrated Search

2011-10-01

This project assessed the physical and chemical characteristics of fly ashes produced from trona injection plants (used for SO2 : emission control), and investigated the leaching of a group of concerned inorganic contaminants from these fly ashes. A ...

Quarterly technical progress report, April-June 1982

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1984-04-01

Progress reports are presented for the following tasks: (1) preparation of low-rank coals; application of liquefaction processes to low-rank coals; (2) slagging fixed-bed gasification; (3) atmospheric fluidized-bed combustion of low-rank coal; (4) ash fouling and combustion modification for low-rank coal; (5) combined flue gas cleanup/simultaneous SO/sub x/-NO/sub x/ control; (6) particulate control and hydrocarbons and trace element emissions from low-rank coals; (7) waste characterization and disposal; and (9) exploratory research.

Determination of ash in coals unusually high in calcite and pyrite

USGS Publications Warehouse

Rees, O.W.; Selvig, W.A.

1942-01-01

The preliminary hearth heating method (A and E) gave results within the A. S. T. M. tolerances for all duplicates obtained in the same laboratory. Checks between different laboratories within A. S. T. M. tolerances were obtained for coals containing up to about 3.6 per cent mineral carbon dioxide, but these ashes contained larger amounts of retained sulfur. The determination of ash by the cold furnace method (B and F) gave duplicate results within A. S. T. M. tolerances for all samples in the U. S. Bureau of Mines laboratory and for samples up to about 1.6 per cent mineral carbon dioxide content in the Illinois Geological Survey laboratory. Checks between average values from the two laboratories were within A. S. T. M. tolerances for all samples.

Flue gas conditioning today

DOE Office of Scientific and Technical Information (OSTI.GOV)

Southam, B.J.; Coe, E.L. Jr.

1995-12-01

Many relatively small electrostatic precipitators (ESP`s) exist which collect fly ash at remarkably high efficiencies and have been tested consistently at correspondingly high migration velocities. But the majority of the world`s coal supplies produce ashes which are collected at much lower migration velocities for a given efficiency and therefore require correspondingly large specific collection areas to achieve acceptable results. Early trials of flue gas conditioning (FGC) showed benefits in maximizing ESP performance and minimizing expense which justified continued experimentation. Trials of several dozen ways of doing it wrong eventually developed a set of reliable rules for doing it right. Onemore » result is that the use of sulfur trioxide (SO{sub 3}) for adjustment of the resistivity of fly ash from low sulfur coal has been widely applied and has become an automatically accepted part of the option of burning low sulfur coal for compliance with the Clean Air Act of l990 in the U.S.A. Currently, over 100,000 MW of generating capacity is using FGC, and it is estimated that approximately 45,800 MW will utilize coal-switching with FGC for Clean Air Act emission compliance. Guarantees that this equipment will be available to operate at least 98 percent of the time it is called upon are routinely fulfilled.« less

Combustion performance characteristics of fine grind fuels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chow, O.K.; Levasseur, A.A.

1996-12-31

The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of Beneficiated Coal-Based Fuels (BCFs) influencing combustion, ash deposition, ash erosion, particulate collection, and emissions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs. To date, twelve beneficiated coal-based fuels have been acquired through PETC and tested at ABB Power Plant Laboratories Fireside Performance Test Facility (FPTF). The results from these fuels indicate that firing the BCFs improved furnace heat transfer andmore » fly ash erosion compared to their respective feed coals. This paper presents the results from a series of combustion test runs recently conducted in the FPTF to address the effect of fuel fineness on performance. A conventionally cleaned at the mine Pittsburgh No. 8 (Emerald mine, Green County, Pennsylvania, Cyprus Coal Company) was acquired and prepared at three grinds (standard, fine and ultra-fine grinds) to evaluate the effect of fuel fineness on combustion performance. The three fuels were tested at firing rates ranging from 3.0 {times} 10{sup 6} Btu/h to 4.0 {times} 10{sup 6} Btu/h, at standard (no staging) and two staged firing conditions.« less

Ash formation, deposition, corrosion, and erosion in conventional boilers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benson, S.A.; Jones, M.L.

1995-12-01

The inorganic components (ash-forming species) associated with coals significantly affect boiler design, efficiency of operation, and lifetimes of boiler parts. During combustion in conventional pulverized fuel boilers, the inorganic components are transformed into inorganic gases, liquids, and solids. This partitioning depends upon the association of the inorganic components in the coal and combustion conditions. The inorganic components are associated as mineral grains and as organically associated elements, and these associations of inorganic components in the fuel directly influence their fate upon combustion. Combustion conditions, such as temperature and atmosphere, influence the volatility and the interaction of inorganic components during combustionmore » and gas cooling, which influences the state and size composition distribution of the particulate and condensed ash species. The intermediate species are transported with the bulk gas flow through the combustion systems, during which time the gases and entrained ash are cooled. Deposition, corrosion, and erosion occur when the ash intermediate species are transported to the heat-transfer surface, react with the surface, accumulate, sinter, and develop strength. Research over the past decade has significantly advanced understanding of ash formation, deposition, corrosion, and erosion mechanisms. Many of the advances in understanding and predicting ash-related issues can be attributed to advanced analytical methods to determine the inorganic composition of fuels and the resulting ash materials. These new analytical techniques have been the key to elucidation of the mechanisms of ash formation and deposition. This information has been used to develop algorithms and computer models to predict the effects of ash on combustion system performance.« less

Coal fly ash interaction with environmental fluids: Geochemical and strontium isotope results from combined column and batch leaching experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brubaker, Tonya M; Stewart, Brian W; Capo, Rosemary C

2013-05-01

The major element and Sr isotope systematics and geochemistry of coal fly ash and its interactions with environmental waters were investigated using laboratory flow-through column leaching experiments (sodium carbonate, acetic acid, nitric acid) and sequential batch leaching experiments (water, acetic acid, hydrochloric acid). Column leaching of Class F fly ash samples shows rapid release of most major elements early in the leaching procedure, suggesting an association of these elements with soluble and surface bound phases. Delayed release of certain elements (e.g., Al, Fe, Si) signals gradual dissolution of more resistant silicate or glass phases as leaching continues. Strontium isotope resultsmore » from both column and batch leaching experiments show a marked increase in {sup 87}Sr/{sup 86}Sr ratio with continued leaching, yielding a total range of values from 0.7107 to 0.7138. For comparison, the isotopic composition of fluid output from a fly ash impoundment in West Virginia falls in a narrow range around 0.7124. The experimental data suggest the presence of a more resistant, highly radiogenic silicate phase that survives the combustion process and is leached after the more soluble minerals are removed. Strontium isotopic homogenization of minerals in coal does not always occur during the combustion process, despite the high temperatures encountered in the boiler. Early-released Sr tends to be isotopically uniform; thus the Sr isotopic composition of fly ash could be distinguishable from other sources and is a useful tool for quantifying the possible contribution of fly ash leaching to the total dissolved load in natural surface and ground waters.« less

Interlaboratory comparison of mutagenesis testing of coal fly ash derived from differenct coal conversion technologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chrisp, C.; Hobbs, C.; Clark, R.

1979-01-01

This experiment showed that mutagenicity of fly ash derived from different coal conversion technologies, as determined by the Ames plate incorporation test, was similar in all three laboratories. The differences in mutagenic activity of each fly ash between laboratories with different solvent extraction methods were no greater than one order of magnitude. In addition, there were much smaller, but still significant differences in mutagenic activity between laboratories when the same solvent extract of a particular fly ash was tested in each laboratory. There were also significant differences in mutagenicity of the positive control mutagen (maximum of fivefold) between laboratories. Becausemore » of this difference in Ames test sensitivity between laboratories, the influence of the solvent extraction methods on differences in mutagenicity was not clear. However, the data suggested that either there were significant differences in the degree of sensitivity of Ames tests for different complex mixtures within each laboratory, or else there were differences in mutagen extraction efficiency between different solvent extraction methods. Both Ames test sensitivity and solvent extraction may be important. Further work would be necessary to separate the contribution of these two factors. An important aspect of further work would be to separate the contribution of the innate sensitivity of substrains of Ames tester strains in each laboratory from the possible effects of differences in Ames testing methodology. This could be done by testing the same extracts of fly ash and positive control mutagens with substrains of tester strains exchanged between laboratories. This work also implies that caution should be exercised in assuming that the same solvent would have the same efficiency for extraction of mutagens from different fly ashes even within the same laboratory.« less

Carbonaceous material production from vegetable residue and their use in the removal of textile dyes present in wastewater

NASA Astrophysics Data System (ADS)

Peláez-Cid, A. A.; Tlalpa-Galán, M. A.; Herrera-González, A. M.

2013-06-01

This paper presents the adsorption results of acid, basic, direct, vat, and reactive-type dyes on carbonaceous adsorbent materials prepared starting off vegetable residue such as Opuntia ficus indica and Casimiroa edulis fruit wastes. The adsorbents prepared from Opuntia ficus indica waste were designated: TunaAsh, CarTunaT, and CarTunaQ. The materials obtained from Casimiroa edulis waste were named: CenZAP, CarZAPT, and CarZAPQ. TunaAsh and CenZAP consist of ashes obtained at 550 °C CarTunaT and CarZAPT consist of the materials carbonized at 400 °C lastly, CarTunaQ and CarZAPQ consist of chemically activated carbons using H3PO4 at 400 °C. Only the chemically activated materials were washed with distilled water until a neutral pH was obtained after their carbonization. All materials were ground and sieved to obtain a particle size ranging from 0.25 to 0.84 mm. The static adsorption results showed that both ashes and chemically activated carbon are more efficient at dye removal for both vegetable residues. For TunaAsh and CarTunaQ, removal rates of up to 100% in the cases of basic, acid, and direct dyes were achieved. Regarding wastewater containing reactive dyes, the efficiency ranged from 60 to 100%. For vat effluents, it ranged from 42 to 52%. In the case of CenZAP and CarZAPQ, it was possible to treat reactive effluents with rates ranging between 63 and 91%. Regarding vat effluents, it ranged from 57 to 68%. The process of characterization for all materials was done using scanning electron microscopy and infrared spectroscopy.

Geochemistry of rare earth elements in Permian coals from the Huaibei Coalfield, China

USGS Publications Warehouse

Zheng, Lingyun; Liu, Gaisheng; Chou, C.-L.; Qi, C.; Zhang, Y.

2007-01-01

The rare earth elements (REEs) in coals are important because of: (a) REE patterns can be an indicator of the nature of source rocks of the mineral matter as well as sedimentary environments; (b) REEs abundance in coal may have industrial-significance. In this study, a total of thirty-four samples of Permian coal, partings, roof, and floor were collected from the Huaibei Coalfield, Anhui Province, China. Abundances of rare earth elements (REEs) and other elements in the samples were determined by inductively coupled-plasma mass spectrometry (ICP-MS) and inductively coupled-plasma atomic emission spectrometry (ICP-AES). The results show that the REEs are enriched in coals in the Huaibei Coalfield as compared with Chinese and U.S. coals and the world coal average. Coals in the Lower Shihezi Formation (No. 7, 5, and 4 Coals) and Upper Shihezi Formation (No. 3) have higher REE abundances than the coals in Shanxi Formation (No. 10). Magmatic intrusion resulted in high enrichment of REEs concentrations in No. 5 and 7 Coals. The REE abundances are positively correlated with the ash content. The mineral matter in these coals is mainly made up of clay minerals and carbonates. The REEs are positively correlated with lithophile elements including Si, Al, Ti, Fe, and Na, which are mainly distributed in clay minerals, indicating that REEs are contained mainly in clay minerals. The REE abundances in coals normalized by the ash are higher than that in partings. REEs abundances of coals cannot be accounted for by the REE content in the mineral matter, and some REEs associated with organic matter in coals. ?? 2007 Elsevier Ltd. All rights reserved.

Method of extracting coal from a coal refuse pile

DOEpatents

Yavorsky, Paul M.

1991-01-01

A method of extracting coal from a coal refuse pile comprises soaking the coal refuse pile with an aqueous alkali solution and distributing an oxygen-containing gas throughout the coal refuse pile for a time period sufficient to effect oxidation of coal contained in the coal refuse pile. The method further comprises leaching the coal refuse pile with an aqueous alkali solution to solubilize and extract the oxidized coal as alkali salts of humic acids and collecting the resulting solution containing the alkali salts of humic acids. Calcium hydroxide may be added to the solution of alkali salts of humic acid to form precipitated humates useable as a low-ash, low-sulfur solid fuel.

Mining geology of the Pond Creek seam, Pikeville Formation, Middle Pennsylvanian, in part of the Eastern Kentucky Coal Field, USA

USGS Publications Warehouse

Greb, S.F.; Popp, J.T.

1999-01-01

The Pond Creek seam is one of the leading producers of coal in the Eastern Kentucky Coal Field. The geologic factors that affect mining were investigated in several underground mines and categorized in terms of coal thickness, coal quality, and roof control. The limits of mining and thick coal are defined by splitting along the margin of the coal body. Within the coal body, local thickness variation occurs because of (1) leader coal benches filling narrow, elongated depressions, (2) rider coal benches coming near to or merging with the main bench, (3) overthrust coal benches being included along paleochannel margins, (4) cutouts occuring beneath paleochannels, and (5) very hard and unusual rock partings occuring along narrow, elongated trends. In the study area, the coal is mostly mined as a compliance product: sulfur contents are less than 1% and ash yields are less than 10%. Local increases in sulfur occur beneath sandstones, and are inferred to represent post-depositional migration of fluids through porous sands into the coal. Run-of-mine quality is also affected by several mine-roof conditions and trends of densely concentrated rock partings, which lead to increased in- and out-of-seam dilution and overall ash content of the mined coal. Roof control is largely a function of a heterolithic facies mosaic of coastal-estuarine origin, regional fracture trends, and unloading stress related to varying mine depth beneath the surface. Lateral variability of roof facies is the rule in most mines. The largest falls occur beneath modern valleys and parallel fractures, along paleochannel margins, within tidally affected 'stackrock,' and beneath rider coals. Shale spalling, kettlebottoms, and falls within other more isolated facies also occur. Many of the lithofacies, and falls related to bedding weaknesses within or between lithofacies, occur along northeast-southwest trends, which can be projected in advance of mining. Fracture-related falls occur independently of lithofacies trends along northwest-southeast trends, especially beneath modern valleys where overburden thickness decreases sharply. Differentiating roof falls related to these trends can aid in predicting roof quality in advance of mining.The Pond Creek-Lower Elkhorn seam has been an important exploration target because it typically has very low sulfur contents and ash yields. Geologic research in several large Pond Creek mines suggested variability in roof quality and coal thickness. Due to mine access, geologic problems encountered during mining are documented and described.

Effect of Trona on the leaching of trace elements from coal fly ash.

DOT National Transportation Integrated Search

2013-07-01

Fly ashes were sampled from the ESPs by on-site contractors during air emission control tests. The injection tests were short-term, : lasting approximately three hours per test condition. EPRI received three batches of samples since November 2011, re...

PREFERENTIAL PARTITIONING OF PAHS AND PCBS TO COAL FLY ASH

EPA Science Inventory

It has long been known that fly ash has a significant capacity for the adsorption of several classes of anthropogenic pollutants, including toxic metals, nutrients and organic compounds. This adsorption capacity has been utilized by wastewater treatment plants for the removal of ...

Identification of potential concerns associated with FDOT use of ammoniated coal fly ash.

DOT National Transportation Integrated Search

2012-12-01

The objectives of this project include a careful examination of the issues surrounding high ammonia content in cement due to the use of ammoniated fly ash. The researchers will gather information from published material and consider policies and prac...

Unburnt carbon from coal fly ashes as a precursor of activated carbon for nitric oxide removal.

PubMed

Rubio, Begoña; Izquierdo, M Teresa; Mayoral, M Carmen; Bona, M Teresa; Andres, Jose M

2007-05-08

The aim of this work is to evaluate the characteristics of an activated carbon obtained from unburnt carbon in coal fly ashes to be used in the removal of NO. Carbon-rich fraction was obtained by mechanical sieving of fly ashes. The mineral matter was removed by conventional HCl and HF demineralization procedure. Activation was carried out with steam at 900 degrees C in order to develop porosity onto the sample. Characterization of samples was performed by several techniques with a main objective: to follow the mineral matter content, composition and distribution on the samples in order to better understand how to remove it from unburnt carbon in fly ashes. To study the use of this unburnt carbon as a precursor for the preparation of activated carbons for gas cleaning, the NO removal by ammonia using activated carbon as a catalyst at low temperature was performed. Results show a good performance of activated carbon in this reaction that is in relationship with BET surface area.

Co-firing of oil sludge with coal-water slurry in an industrial internal circulating fluidized bed boiler.

PubMed

Liu, Jianguo; Jiang, Xiumin; Zhou, Lingsheng; Wang, Hui; Han, Xiangxin

2009-08-15

Incineration has been proven to be an alternative for disposal of sludge with its unique characteristics to minimize the volume and recover energy. In this paper, a new fluidized bed (FB) incineration system for treating oil sludge is presented. Co-firing of oil sludge with coal-water slurry (CWS) was investigated in the new incineration system to study combustion characteristics, gaseous pollutant emissions and ash management. The study results show the co-firing of oil sludge with CWS in FB has good operating characteristic. CWS as an auxiliary fuel can flexibly control the dense bed temperatures by adjusting its feeding rate. All emissions met the local environmental requirements. The CO emission was less than 1 ppm or essentially zero; the emissions of SO(2) and NO(x) were 120-220 and 120-160 mg/Nm(3), respectively. The heavy metal analyses of the bottom ash and the fly ash by ICP/AES show that the combustion ashes could be recycled as soil for farming.

Belite cement clinker from coal fly ash of high Ca content. Optimization of synthesis parameters.

PubMed

Guerrero, A; Goñi, S; Campillo, I; Moragues, A

2004-06-01

The optimization of parameters of synthesis of belite cement clinker from coal fly ash of high Ca content is presented in this paper. The synthesis process is based on the hydrothermal-calcination-route of the fly ash without extra additions. The hydrothermal treatment was carried out in demineralized water and a 1 M NaOH solution for 4 h at the temperatures of 100 degrees C, 150 degrees C, and 200 degrees C. The precursors obtained during the hydrothermal treatmentwere heated at temperatures of 700 degrees C, 800 degrees C, 900 degrees C, and 1000 degrees C. The changes of fly ash composition after the different treatments were characterized by X-ray diffraction (XRD), FT infrared (FTIR) spectroscopy, surface area (BET-N2), and thermal analyses. From the results obtained we concluded that the optimum temperature of the hydrothermal treatment was 200 degrees C, and the optimum temperature for obtaining the belite cement clinker was 800 degrees C.

Trace element geochemistry and mineralogy of coal from Samaleswari open cast coal block (S-OCB), Eastern India

NASA Astrophysics Data System (ADS)

Saha, Debasree; Chatterjee, Debashis; Chakravarty, Sanchita; Mazumder, Madhurina

2018-04-01

Coal samples of Samaleswari open cast coal block (S-OCB) are high ash (Aad, mean value 35.43%) and low sulphur content (St, on dry basis, mean value 0.91% < 1%) in quality. The stratigraphic variation of volatile matter and fixed carbon (dry ash-free) reflect a progress of coal metamorphism with depth that accordance to the coal rank variation from lignite to high volatile bituminous in the studied borehole. The younger coal seams have greater detrital minerals (quartz, illite, rutile) influence whereas older coal seams have greater authigenic mineral (kaolinite, dolomite, siderite, apatite) contribution that are possibly due to subsidence and sediment transportation. In S-OCB coal trace elements affinities in-between mineral and organic fraction are identified with statistical hierarchical cluster analysis. The work is further supported by the use of chemical fractionation experiment that reveals the multi mode of occurrence of several environmentally concern and interested trace elements (Sb, As, Be, Cd, Cr, Co, Cu, Pb, Mn, Ni, Zn). Among the analysed trace elements Co, Mn and Zn have major silicate association along with significant carbonate/oxide/monosulfide association. Whereas As, Cd, Cu, Pb and Ni have dominant pyritic association with notable silicate and carbonate/oxide/monosulfide association. The rest three elements (Sb, Be, Cr) have principally organic association with minor silicate and carbonate/oxide/monosulfide association. The stratigraphic variation of organo-mineral matrix content and detrital-authigenic mineral ratio are primarily related to coal rank. Geochemical character of coal also reflects a light towards proper utilisation of S-OCB coal from technical and environmental view point.

Soil amendments promote vegetation establishment and control acidity in coal combustion waste

Treesearch

R.M. Danker; D.C. Adriano; Bon-Jun Koo; C.D. Barton

2003-01-01

The effects of adding various soil amendments and a pyrite oxidation inhibitor to aid in the establishment of vegetation and to reduce acid drainage (AD) from coal fly ash and coal reject (FA + CR*) were assessed in an outdoor mesocosm study. Preliminary greenhouse experiments and field observations at the U.S. Department of Energy's Savannah River Site (SRS)...

Palaeoenvironmental reconstruction of Hüsamlar coal seam, SW Turkey

NASA Astrophysics Data System (ADS)

Büçkün, Zeynep; İnaner, Hülya; Oskay, Riza Görkem; Christanis, Kimon

2015-06-01

The Ören and Yatağan Basins in SW Turkey host several Miocene coal deposits currently under exploitation for power generation. The present study aims to provide insight into the palaeoenvironmental conditions, which controlled the formation of the Hüsamlar coal seam located in Ören Basin. The coal seam displays many sharp alternations of matrix lignite beds and inorganic, lacustrine sediment layers. The coal is a medium-to-high ash lignite (10.47-31.16 wt%, on dry basis) with high total sulphur content (up to 10 wt%, on dry, ash-free basis), which makes it prone to self-combustion. The maceral composition indicates that the peat-forming vegetation consisted of both arboreal and herbaceous plants, with the latter being predominant in the upper part of the seam. Mica and feldspars contribute to the low part of the seam; carbonates are dominant in the upper part, whereas quartz and pyrite are present along the entire coal profile. The sudden transitions of the telmatic to the lacustrine regime and reverse is attributed to tectonic movements that controlled water table levels in the palaeomire, which affected surface runoff and hence, clastic deposition.

Synfuels and the energy transition

NASA Astrophysics Data System (ADS)

Balzhiser, R. E.

1981-08-01

Various synfuel options and their impact on the electric utility industry are discussed. The energy transition for the U.S.A. is seen as moving from natural fluid fuels to solid fuels and renewable energy resources. The key to this transition is electrification, which can encompass both nuclear and renewable resources, centralized and dispersed technologies. It is shown that the fraction of total energy converted to electricity has risen steadily for the past 30 years, reaching 33% last year. The abundance and cost of production of the various fossil energy resources, including natural gas, heavy oil, oil shale, and coal are considered. EPRI analyses indicate that an integrated-combined-cycle power plant could be competitive with conventional coal plant technology. These plants would use only half the water of current coal-fired plants, would meet tighter sulfur emission standards, and would produce a vitreous ash that is less leachable than the ash from today's coal plants. Solvent-refined coal processes, currently being developed in the U.S.A. are a second approach to converting coal to liquid fuels. It is pointed out, however, that synfuels will complement, not replace, other sources of energy in the continued electrification of the U.S.A.