Sample records for lignite quality variation
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Future of lignite resources: a life cycle analysis.
Wang, Qingsong; Liu, Wei; Yuan, Xueliang; Zheng, Xiaoning; Zuo, Jian
2016-12-01
Lignite is a low-quality energy source which accounts for 13 % of China's coal reserves. It is imperative to improve the quality of lignite for large-scale utilization. To further explore and analyze the influence of various key processes on the environment and economic costs, a lignite drying and compression technology is evaluated using an integrated approach of life cycle assessment and life cycle costs. Results showed that lignite mining, direct air emissions, and electricity consumption have most significant impacts on the environment. An integrated evaluation of life cycle assessment and life cycle costs showed that the most significant contributor to the environmental impacts and economic costs was the lignite mining process. The impact of transportation and wastewater treatment process on the environment and economic costs was small enough to be ignored. Critical factors were identified for reducing the environmental and economic impacts of lignite drying and compression technology. These findings provide useful inputs for both industrial practice and policy making for exploitation, processing, and utilization of lignite resources.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Yilmaz, A.O.
Total coal reserve (hard coal + lignite) in the world is 984 billion tons. While hard coal constitutes 52% of the total reserve, lignite constitutes 48% of it. Turkey has only 0.1% of world hard coal reserve and 1.5% of world lignite reserves. Turkey has 9th order in lignite reserve, 8th order in lignite production, and 12th order in total coal (hard coal and lignite) consumption. While hard coal production meets only 13% of its consumption, lignite production meets lignite consumption in Turkey. Sixty-five percent of produced hard coal and 78% of produced lignite are used for electricity generation. Lignitesmore » are generally used for electricity generation due to their low quality. As of 2003, total installed capacity of Turkey was 35,587 MW, 19% (6,774 MW) of which is produced from coal-based thermal power plants. Recently, use of natural gas in electricity generation has increased. While the share of coal in electricity generation was about 50% for 1986, it is replaced by natural gas today.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Ayers, W.B. Jr.; Lewis, A.H.
1984-04-01
Deep lignite resources (200-2000 ft; 61-610 m) were evaluated regionally using 1470 geophysical well logs to interpret lithofacies, lignite occurrence, and resistivity (water quality). The regional distribution of lithofacies indicates that in the region, the Wilcox Group is a fluvial-deltaic system. The primary fluvial system entered the Wilcox coastal plain west of Waco, Texas, trended southeast, and supplied a 75-mi (120-km) wide fluvial-deltaic system comparable in size to the Mississippi system. Lignites are most abundant in the Calvert Bluff Formation (upper Wilcox). Lower Calvert Bluff lignites are thickest and most extensive southwest of the Navasota River, whereas those of themore » upper Calvert Bluff are thickest northeast of the Brazos River. In the shallow subsurface, Calvert Bluff lignites are found in dip-elongate low-sand areas (flood plains) between channel-sand belts. Basinward, laterally continuous lignites coincide with high net sand areas comprise of distributary channel sands indicative of a delta-plain setting. The wilcox Group is a major aquifer. Maps of resistivity values show that Wilcox channel sands are conduits for ground-water flow. High values of formation resistivity (low total dissolved solids) exist in recharge areas at outcrop and around salt domes. Elongate trends of high resistivity values extend tens of miles basinward and coincide with axes of major sands. Resistivity values decrease basinward and the 20 ohm-m contour delineates the downdip limit of fresh water. Lithofacies and lignite occurrence maps are guides to exploration for deep lignite. Resistivity maps can be used to explore for ground-water resources.« less
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A review of lignite resources of western Tennessee and the Jackson Purchase area, western Kentucky
Hackley, Paul C.; Warwick, Peter D.; Thomas, Roger E.; Nichols, Douglas J.; Warwick, Peter D.; Karlsen, Alexander K.; Merrill, Matthew D.; Valentine, Brett J.
2011-01-01
This review of the lignite deposits of western Tennessee and the Jackson Purchase area in western Kentucky (Figure 1) is an updated report on part of the U.S. Geological Survey's National Coal Resource Assessment of the Gulf Coastal Plain Coal Province (see Ruppert et al., 2002; Hackley et al., 2006; Dennen, 2009; and other chapters of this publication). Lignite deposits of western Kentucky and Tennessee are an extension of the Gulf Coastal Plain Coal Province (Cushing et al., 1964), and currently are not economic to mine. These deposits have not been extensively investigated or developed as an energy resource. This review includes a description of the geology of the lignite-bearing units, a discussion of the available coal quality data, and information on organic petrology. Palynological data for lignite samples collected in Kentucky and Tennessee as part of this work are presented in Table 1. Lignite trace element data originally presented in Hackley et al. (2006) are not included in this report due to potential laboratory quality control issues during the time the samples were analyzed (U.S. Geological Survey Energy Resources Program, 2010).
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A preliminary report on a zone containing thick lignite beds, Denver Basin, Colorado
Soister, Paul E.
1973-01-01
A zone of lignite beds of Paleocene age in the Denver Formation (Upper Cretaceous and Paleocene) lies about 800-1,500 feet above the well-known and extensively mined coal beds of the Laramie Formation (Upper Cretaceous). The zone is a few hundred to as much as 500 feet thick. Where lignite beds lie within 1,000 feet of the surface, this zone underlies an area about 30 miles wide by about 75 miles long, stretching from just northeast of Denver to several miles south of Calhan. Fifteen mines were operated at various periods between 1874 and 1940 and probably produced a total of less than 100,000 tons of lignite, mostly for local use. From 1874 to 1974, several geologists have reported on this lignite zone or the enclosing beds, but no detailed reports have been written except for one by this writer. Drill holes are the main source of geologic data, owing to poor exposure. There are generally about 3 to 6 lignite beds, and they are mostly about 15 or 20 to a few tens of feet apart. Most or all beds typically contain numerous non-coal partings from a fraction of an inch to several inches thick, so that thickness of lignite beds should be stated as gross thickness and as net lignite thickness; net lignite thickness is generally from 70 to 90 percent of gross thickness. Many partings are composed of kaolin, but others are composed of other clay minerals, siltstone, and sandstone. The lignite beds range generally from 1 or 2 to several feet thick, and some are as much as 10-25 feet thick; the thickest known bed has a maximum thickness of 54.5 feet, with a net lignite thickness of 40 feet. Most lignite beds seem to have fair lateral continuity, and at least some beds are several miles in extent. The thickest known lignite bed was traced for at least 18 miles, from northwest to southeast of Watkins. The lignite is brownish-black to black, weathers, checks, and disintegrates rapidly, and even in drill cores from a few hundred feet in depth the lignite is easily broken by hand pressure. Quality of the lignite is lowered by the non-coal partings and, locally at least, by some small blebs and balls of clay in the lignite itself, especially at the base. Available analyses indicate that the following general figures, on an as-received basis, may be applied to relatively clean lignite from this zone: 6,000-7,000 Btu, 20-35 percent moisture, 8-18 percent ash, and 0.3-0.5 percent sulfur. Rank of the lignite is lignite A as calculated by the formulas of the American Society for Testing and . Materials (ASTM), although some parts, especially of deeper beds, may be as high as subbituminous C coal in rank. Best utilization of the lignite probably would be by gasification, liquefaction, or similar methods, because of the numerous non-coal partings and low quality. The thickest known lignite bed is estimated to contain at least 1.25 billion short tons of lignite. Two methods of roughly estimating the order of magnitude of lignite resources, in beds at least 4 feet thick and within 1,000 feet of the surface in this zone, indicate resources are on the order of 20 billion tons.
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Warwick, Peter D.; Crowley, Sharon S.
1995-01-01
The Jackson and Wilcox Groups of eastern Texas (fig. 1) are the major lignite producing intervals in the Gulf Region. Within these groups, the major lignite-producing formations are the Paleocene-Eocene Calvert Bluff Formation (Wilcox) and the Eocene Manning Formation (Jackson). According to the Keystone Coal Industry Manual (Maclean Hunter Publishing Company, 1994), the Gulf Coast basin produces about 57 million short tons of lignite annually. The state of Texas ranks number 6 in coal production in the United States. Most of the lignite is used for electric power generation in mine-mouth power plant facilities. In recent years, particular interest has been given to lignite quality and the distribution and concentration of about a dozen trace elements that have been identified as potential hazardous air pollutants (HAPs) by the 1990 Clean Air Act Amendments. As pointed out by Oman and Finkelman (1994), Gulf Coast lignite deposits have elevated concentrations of many of the HAPs elements (Be, Cd, Co, Cr, Hg, Mn, Se, U) on a as-received gm/mmBtu basis when compared to other United States coal deposits used for fuel in thermo-electric power plants. Although regulations have not yet been established for acceptable emissions of the HAPs elements during coal burning, considerable research effort has been given to the characterization of these elements in coal feed stocks. The general purpose of the present field trip and of the accompanying collection of papers is to investigate how various aspects of east Texas lignite geology might collectively influence the quality of the lignite fuel. We hope that this collection of papers will help future researchers understand the complex, multifaceted interrelations of coal geology, petrology, palynology and coal quality, and that this introduction to the geology of the lignite deposits of east Texas might serve as a stimulus for new ideas to be applied to other coal basins in the U.S. and abroad.
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A comparison of thermal behaviors of raw biomass, pyrolytic biochar and their blends with lignite.
Liu, Zhengang; Balasubramanian, Rajasekhar
2013-10-01
In this study, thermal characteristics of raw biomass, corresponding pyrolytic biochars and their blends with lignite were investigated. The results showed that pyrolytic biochars had better fuel qualities than their parent biomass. In comparison to raw biomass, the combustion of the biochars shifted towards higher temperature and occurred at continuous temperature zones. The biochar addition in lignite increased the reactivities of the blends. Obvious interactions were observed between biomass/biochar and lignite and resulted in increased total burnout, shortened combustion time and increased maximum weight loss rate, indicating increased combustion efficiencies than that of lignite combustion alone. Regarding ash-related problems, the tendency to form slagging and fouling increased, when pyrolytic biochars were co-combusted with coal. This present study demonstrated that the pyrolytic biochars were more suitable than raw biomass to be co-combusted with lignite for energy generation in existing coal-fired power plants. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Review of lignite resources of western Tennessee and the Jackson Purchase area, western Kentucky
Hackley, Paul C.; Warwick, Peter D.; Thomas, Roger E.; Nichols, Douglas J.
2006-01-01
Introduction: This review of the lignite deposits of western Tennessee and the Jackson Purchase area in western Kentucky (Fig. 1) is a preliminary report on part of the U.S. Geological Survey's National Coal Resource Assessment of the Gulf Coastal Plain Coal Province. Lignite deposits of western Kentucky and Tennessee are an extension of the Gulf Coastal Plain Coal Province (Cushing and others, 1964), and currently are not economic to mine. These deposits have not been extensively investigated or developed as an energy resource. This review includes a description of the geology of the lignite-bearing units, a discussion of the available coal quality data, and information on organic petrology. Palynological data for lignite samples collected in Kentucky and Tennessee as part of this work are presented in an Appendix.
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A review of the lignite resources of Arkansas
Willett, Jason C.; Hackley, Paul C.; Warwick, Peter D.; S.J. Law,; Nichols, Douglas J.; Warwick, Peter D.; Karlsen, Alexander K.; Merrill, Matthew D.; Valentine, Brett J.
2011-01-01
This review of the lignite resources of Arkansas is a part of the U.S. Geological Survey’s (USGS) National Coal Resource Assessment (NCRA) of the Gulf Coastal Plain Coal Province, which also includes coal-bearing areas in the states of Texas, Louisiana, Alabama, Mississippi, Tennessee, and Kentucky (see Ruppert et al., 2002; Dennen, 2009; and other chapters of this publication). Lignite mining is not planned in Arkansas in the immediate future, and the lignite resources of the state were not assessed in detail as part of the NCRA. This chapter includes reviews of the geology of the lignite-bearing units, historical mining, previous investigations of lignite resources, and coal quality. Palynological data for lignite samples collected in Arkansas as part of this work are presented in Table 1.The lignite-bearing stratigraphic units of Arkansas are part of the Mississippi Embayment of the Gulf Coastal Plain, a trough of Cretaceous through Quaternary sedimentary strata that plunge gently southward along an axis that generally is coincident with the course of the Mississippi River (Figure 1) (Cushing et al., 1964). The sedimentary strata of the Gulf Coastal Plain of Arkansas are, in general, flat-lying or gently dipping southeastward to eastward toward the embayment axis. Coal and lignite occur in Cretaceous through Tertiary strata of Arkansas and previously have been investigated in two principal regions within the State where units of these ages crop out: south-central Arkansas (West Gulf Coastal Plain) and Crowley’s Ridge in the northeastern part of the State (Figure 2).
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Simulation of 0.3 MWt AFBC test rig burning Turkish lignites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Selcuk, N.; Degirmenci, E.; Oymak, O.
1997-12-31
A system model coupling bed and freeboard models for continuous combustion of lignite particles of wide size distribution burning in their own ash in a fluidized bed combustor was modified to incorporate: (1) a procedure for faster computation of particle size distributions (PSDs) without any sacrifice in accuracy; (2) energy balance on char particles for the determination of variation of temperature with particle size, (3) plug flow assumption for the interstitial gas. An efficient and accurate computer code developed for the solution of the conservation equations for energy and chemical species was applied to the prediction of the behavior ofmore » a 0.3 MWt AFBC test rig burning low quality Turkish lignites. The construction and operation of the test rig was carried out within the scope of a cooperation agreement between Middle East Technical University (METU) and Babcock and Wilcox GAMA (BWG) under the auspices of Canadian International Development Agency (CIDA). Predicted concentration and temperature profiles and particle size distributions of solid streams were compared with measured data and found to be in reasonable agreement. The computer code replaces the conventional numerical integration of the analytical solution of population balance with direct integration in ODE form by using a powerful integrator LSODE (Livermore Solver for Ordinary Differential Equations) resulting in two orders of magnitude decrease in CPU (Central Processing Unit) time.« less
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Co-combustion of pellets from Soma lignite and waste dusts of furniture works
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deveci, N.D.; Yilgin, M.; Pehlivan, D.
2008-07-01
In this work, volatiles and char combustion behaviors of the fuel pellets prepared from a low quality lignite and the dusts of furniture works and their various blends were investigated in an experimental fixed bed combustion system through which air flowed by natural convection. Combustion data obtained for varied bed temperatures, mass of pellets, and blend compositions has showed that ignition times of the pellets decreased and volatiles combustion rates tended to increase with the burning temperature. It was concluded that some synergy had existed between lignite and lower ratios of furniture work dusts, which was indicated by a promptmore » effect on the volatiles combustion rates. Char combustion rates of blend pellets have depended predominantly on the amount of lignite in the blend. The amounts of combustion residues of the pellets were considerably higher than those calculated from individual ash contents of the raw materials and related to lignite ratio in the blends.« less
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Hydrologic and geochemical data for the Big Brown lignite mine area, Freestone County, Texas
Dorsey, Michael E.
1985-01-01
Lignite mining in east and east-central Texas is increasing in response to increased energy needs throughout the State. Associated with the increase in mining activities is a greater need to know the effects of mining activities on the water quantity and quality of near-surface aquifers. The near-surface lignite beds mined at the Big Brown Lignite Mine are from the Calvert Bluff Formation of the Wilcox Group of Eocene age, which is a minor aquifer generally having water suitable for all uses, in eastern Freestone County, Texas. One of the potential hydro!ogic effects of surface-coal mining is a change in the quality of ground water associated with replacement of aquifer materials by mine spoils. The purpose of this report is to compile and categorize geologic, mineralogic, geochemical, and hydrologic data for the Big Brown Lignite Mine and surrounding area in east-central Texas. Included are results of pasteextract analyses, constituent concentrations in water from batch-mixing experiments, sulfur analyses, and minerals or mineral groups detected by X-ray diffraction in 12 spoil material samples collected from 3 locations at the mine site. Also, common-constituent and trace-constituent concentrations in water from eight selected wells, located updip and downdip from the mine, are presented. Dissolved-solids concentrations in water from batch-mixing experiments vary from 12 to 908 milligrams per liter. Water from selected wells contain dissolved-solids concentrations ranging from 75 to 510 milligrams per liter.
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Stratigraphic framework and distribution of lignite on Crowleys Ridge, Arkansas
Meissner, Charles R.
1983-01-01
The purpose of this report is to establish a stratigraphic framework of lignite beds and associated strata of Crowleys Ridge, Arkansas. Drill hole data provided by the Arkansas Geological Commission is used in the synthesis and interpretation. Areas containing lignite of potential resource value are also delineated. To illustrate the regional stratigraphic framework of Crowleys Ridge, a cross section was constructed from logs of selected oil and gas test wells, along or adjacent to the north-south trending ridge over a distance of about 115 miles. This section reveals that lignite-bearing Tertiary formations dip gently southward along the ridge. The Paleocene-Eocene Wilcox Group forms the bedrock in the northern part of the ridge and successively younger bedrock of the Eocene Claiborne and Jackson Groups is identified in the central and southern part of the ridge. Crowleys Ridge is mantled with alluvium and loess of Quaternary age, and sand and gravel beds of the Lafayette Formation of Pliocene (?) age that unconformably overlie the Paleocene and Eocene rocks. The thickness of lignite-bearing sedimentary deposits ranges from 830 feet in the north to 2,480 feet in the south. The Wilcox, Claiborne, and Jackson Groups of Paleocene and Eocene age are believed to be fluvial-deltaic in origin. The detailed vertical and horizontal stratigraphic characteristics and distribution of lignite beds in the sediments were determined by constructing seven cross sections from lithologic and geophysical logs of the lignite investigations on Crowleys Ridge by the Arkansas Geological Commission and private companies. Correlation and interpretation of the lignite-bearing strata reveal ten lignite beds of resource potential. These lignite beds range from a few inches to 9.5 ft in thickness and are assigned to stratigraphic intervals that are designated as zone 1 through 7. Zone 1 is near the middle of the Wilcox Group and zone 7 is near the middle of the overlying Claiborne Group. Some of these lignite beds are correlated over distances as much as 30 miles. Other lignite beds thin to a few inches thick and disappear within short distances. Four areas are delineated on Crowleys Ridge that contain one or more lignite beds each 2.5 feet or more thick. Strippable lignite is limited to 300 feet in this area, therefore, all holes were drilled to 300 feet or less. Chemical analyses of eight lignite samples from Crowleys Ridge are on record with the U.S. Geological Survey's National Coal Resources Data System. Two of the samples are from the Wilcox Group, and six are from the Claiborne Group, but the lignite beds from which the samples were taken are unidentified. However, the analyses are believed to be representative of the lignite within the lignite-bearing sequence. The two Wilcox samples had moisture values of 36.3 and 40.1 percent; ash, 30.5 and 20.5 percent (U.S. Bureau of Mines); sulfur content, 0.3 and 1.0 percent; and Btu values, 3,910 and 4,590 on an as received basis. The six Claiborne samples had moisture values ranging from 34.7 to 43.7 percent; ash from 11.9-28.2 percent (USBM); sulfur content, 0.3-3 percent; and Btu values, 3,400 to 5,160. U.S. Geological Survey average ash content for the eight samples was 36.22 percent, and the major oxides are SiO2 (60.75 percent), Al2O3 (15.23 percent), CaO (6.96 percent), Fe2O3 (6.65 percent), and SO3 (5.64 percent). No anomalous values were recorded for the trace element content. Lignite is not currently mined on Crowleys Ridge. It has potential for use as a fuel for direct firing of boilers to generate electricity. It also has potential for gasification to produce pipeline gas, and for liquefaction to produce fuel oil. More drilling and analyses are needed to better define the quantity and quality of lignite beds within the four significant areas with resource potential and to determine the extent of lignite beds 2.5 ft or more thick that occur in several isolated areas.
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Triantafyllou, A G; Zoras, S; Evagelopoulos, V
2006-11-01
Lignite mining operations and lignite-fired power stations result in major particulate pollution (fly ash and fugitive dust) problems in the areas surrounding these activities. The problem is more complicated, especially, for urban areas located not far from these activities, due to additional contribution from the urban pollution sources. Knowledge of the distribution of airborne particulate matter into size fraction has become an increasing area of focus when examining the effects of particulate pollution. On the other hand, airborne particle concentration measurements are useful in order to assess the air pollution levels based on national and international air quality standards. These measurements are also necessary for developing air pollutants control strategies or for evaluating the effectiveness of these strategies, especially, for long periods. In this study an attempt is made in order to investigate the particle size distribution of fly ash and fugitive dust in a heavy industrialized (mining and power stations operations) area with complex terrain in the northwestern part of Greece. Parallel total suspended particulates (TSP) and particulate matter with an aerodynamic diameter less than 10 microm (PM10) concentrations are analyzed. These measurements gathered from thirteen monitoring stations located in the greater area of interest. Spatial, temporal variation and trend are analyzed over the last seven years. Furthermore, the geographical variation of PM10 - TSP correlation and PM10/TSP ratio are investigated and compared to those in the literature. The analysis has indicated that a complex system of sources and meteorological conditions modulate the particulate pollution of the examined area.
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NASA Astrophysics Data System (ADS)
Weber, M. E.; Tougiannidis, N.; Ricken, W.; Rolf, C.; Kleineder, M.; Bertram, N.; Antoniadis, P.
2009-04-01
We recently commenced a project to investigate deep drillings as well as outcrops in the Ptolemais Basin, northern Greece, for paleoenvironmental and paleoclimate change. Specific attention is paid to mining sites Achlada, Vevi, Vegora, Amynteon, North Field, South Field, and Lava. The sediment archive comprises Upper Miocene to Quaternary continental lake deposits (up to 800 m thick) with an extended Lower Pliocene section. The Upper Miocene sections are composed of diatomaceous mud and gray marls. Pliocene lake sediments commence with the Kyrio member (lignite/grey marl), followed by the Theodoxus member (beige marl/lignite), and the Notio member (marl with intercalated sand /lignite). The limnic deposits show striking rhythmic bedding of (mostly) carbonates and lignites, reflecting orbital-induced humidity and temperature changes in this small NW-SE elongated continental basin. First, we retrieved chronometric information by determining magnetic polarity changes on three sites as independent stratigraphic ground-truth in combination with palynological evidence and published data. Then we conducted a number of high-resolution (1 - 6 cm increment), non-destructive measurements to obtain paleoclimate proxies: photospectrometry (colors L, a, b), magnetic susceptibility, and natural gamma. Accordingly, we achieved a multi-proxy insight into paleoclimate and paleoenvironmental evolution at unprecedented temporal resolution (up to a few decades!) over long time series and at a number of key sites. Using the newly-developed ESALab software, we conducted spectral and evolutionary spectral analysis to evaluate the cyclo-stratigraphic development. As for orbital variability, spectral power is concentrated on precession, hemi-precession, and eccentricity, with only minor impact of orbital tilt. We used this information to increase the temporal resolution of our age models by tuning as many precession (insolation) maxima as possible to carbonate minima (lignite maxima), assuming that the lignite phase is associated with maximum temperature and humidity. The reason to apply the tuning was primarily to obtain a better temporal control on the cyclicity documented in the suborbital frequency band. These higher-frequency variations provide a significant contribution and visually resemble those that have been documented for the Greenland Ice Sheet during the last glacial cycle. Future goals of our work include the establishment of possible teleconnections to other parts of the global climate system. We would like to evaluate (i) how the aridification of the Messinian salinity crisis affected the Upper Miocene limnic record, (ii) why the lignite production was enhanced during the warm Lower Pliocene and how the link to the warm global climate might have been created, and (iii) whether the massive northern hemisphere glaciation during the Upper Pliocene might have contributed to the termination of lignite formation in the Ptolemais Basin.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Balat, M.
The objective of this study is to determine the lignite use for Turkey's energy necessity. Lignite is the most important energy resource of Turkey when compared with others according to the amount of reserves. Lignite is the dominant source of energy produced (43%) in Turkey. Lignite deposits are encountered in almost every region of Turkey. Total lignite reserves are estimated at 8,375 million tons, of which 7,340 million tons (88%) is economically feasible. Share of lignite reserves of Turkey are 2% in the world. Lignite deposits are encountered in almost every region of Turkey. Afsin-Elbistan, Mugla, Soma, Tuncbilek, Seyitomer, Beypazarimore » and Sivas basins constitutes the most important known lignite reserves. The biggest lignite deposits, 40% of the total, are in Afsin-Elbistan. Lignite extraction is expected to increase as the government feels pressure to close down unprofitable hard coal mines that are geologically difficult, increasing the cost of extraction.« less
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Horak, W.F.; Crosby, O.A.
1985-01-01
The Avoca lignite deposit in the Sentinel Butte Member of the Fort Union Formation consists of four potentially strippable lignite beds. Average bed thicknesses, in descending order, are 5, 5, 9, and 8 .feet. In the area between Stony Creek and Crazy Man Coulee, the lignite beds are unsaturated, and between Stony Creek and Little Muddy River, only the two lowest beds are saturated. Natural discharge to outcrops in the stream valleys results in low potentiometric levels in the lignite beds.Aquifers in sandstone beds in the Fox Hills Sandstone and the Hell Creek Formation probably would yield as much as 50 gallons per minute of sodium bicarbonate type water. Dissolved-solids concentrations range from 800 to 2,000 milligrams per liter. The aquifers are from 1,100 to 1,800 feet below land surface. Sandstone beds in the Ludlow and Cannonball Members of the Fort Union Formation probably could yield several gallons per minute of sodium bicarbonate water with dissolved-solids concentrations ranging from 800 to 2,000 milligrams per liter. Aquifers in the Ludlow and Cannonball Members lie between 700 and 1,300 feet below land surface. Individual sand beds in the Tongue River and Sentinel Butte Members of the Fort Union Formation are the shallowest aquifers encountered below the minable lignite beds. Properly constructed wells completed in these sand beds could yield as much as 40 gallons per minute. The water generally is a sodium bicarbonate type with dissolved-solids concentrations ranging from about 500 to 4,200 milligrams per liter. Alluvium and glacial-drift deposits constitute the Little Muddy aquifer bordering the lignite deposit on the west and south. The aquifer could yield as much as 1,200 gallons per minute of sodium bicarbonate type water with dissolved-solids concentrations ranging from 975 to 1, 730 milligrams per liter.Little Muddy Creek and Stony Creek have significant base flow. The flow is contributed partly by discharge from the lignite. Quality of water is least mineralized at high stream flows. Mining would not severely affect ground-water levels because potentiometric levels already are low. Chemically enriched leachate water from the spoils could percolate to the saturated zone and eventually reach the streams as base flow or recharge the glaciofluvial aquifers.
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NASA Astrophysics Data System (ADS)
Steenbrink, J.; Kloosterboer-van Hoeve, M. L.; Hilgen, F. J.
2003-03-01
Quaternary climate proxy records show compelling evidence for climate variability on time scales of a few thousand years. The causes for these millennial-scale or sub-Milankovitch cycles are still poorly understood, not least due to the complex feedback mechanisms of large ice sheets during the Quaternary. We present evidence of millennial-scale climate variability in Early Pliocene lacustrine sediments from the intramontane Ptolemais Basin in northwestern Greece. The sediments are well exposed in a series of open-pit lignite mines and exhibit a distinct millennial-scale sedimentary cyclicity of alternating lignites and lacustrine marl beds that resulted from precession-induced variations in climate. The higher-frequency, millennial-scale cyclicity is particularly prominent within the grey-coloured marl segment of individual cycles. A stratigraphic interval of ˜115 ka, covering five precession-induced sedimentary cycles, was studied in nine parallel sections from two open-pit lignite mines located several km apart. High-resolution colour reflectance records were used to quantify the within-cycle variability and to determine its lateral continuity. Much of the within-cycle variability could be correlated between the parallel sections, even in fine detail, which suggests that these changes reflect basin-wide variations in environmental conditions related to (regional) climate fluctuations. Interbedded volcanic ash beds demonstrate the synchronicity of these fluctuations and spectral analysis of the reflectance time series shows a significant concentration of within-cycle variability at periods of ˜11, ˜5.5 and ˜2 ka. The occurrence of variability at such time scales at times before the intensification of the Northern Hemisphere glaciation suggests that they cannot solely have resulted from internal ice-sheet dynamics. Possible candidates include harmonics or combination tones of the main orbital cycles, variations in solar output or periodic motions of the Earth and Moon.
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OXIDATION AND DEVOLATILIZATION OF NITROGEN IN COAL CHAR
The reactions of organically-bound nitrogen in coal char during combustion have been studied in a laboratory furnace using size-graded char particles prepared by the pyrolysis of a Montana lignite. The time-resolved variations of nitrogen-to-carbon ratio during char oxidation hav...
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Yen, Teh Fu
1987-03-01
Anaerobic fermentation of water soluble fraction of modified lignite was attempted. Solubilized lignite formed bioprecipitate after biodegradation. Fermentation of water solubilized lignite in enrichment media produced gases and organic acids. FT-IR spectra of solubilized lignite after biodegradation showed that the concentration of organic oxygen have decreased and that the concentration of -CH/sub 3/ terminal group have increased. Solubilized lignite may serve as sole carbon source by using selective media. Bacteria was suspected of being able to utilize fulvic-like materials from solubilized lignite. Isolation of anaerobic bacteria was achieved by surface culture, and it indicated morphological differences among isolated colonies. Alginatemore » gel entrapment, an immobilization method, was applied to T. versicolor fungal cells. Active fungal growth was observed from the immobilized spheres on sodium-alginate gel. It seems that the immobilized biocatalysts may be used to enhance the production of bioextract from lignite in a reactor system. Hydroxylation of lignite was accomplished through Fenton reaction at pH 7.5. FT-IR analysis showed that lignite treated with Fenton's reagent exhibits weaker aromatic bending and ether linkage than untreated lignite. 13 refs., 8 figs.« less
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Hoadley, A F A; Qi, Y; Nguyen, T; Hapgood, K; Desai, D; Pinches, D
2015-10-01
Dried sludge is preferred when the sludge is either to be incinerated or used as a soil amendment. This paper focuses on superheated steam drying which has many benefits, because the system is totally enclosed, thereby minimising odours and particulate emissions. This work reports on field trials at a wastewater treatment plant where anaerobically digested sludge is dried immediately after being dewatered by belt press. The trials showed that unlike previous off-site tests, the sludge could be dried without the addition of a filter aid at a low production rate. However, the trials also confirmed that the addition of the lignite (brown coal) into the anaerobically digested sludge led to a more productive drying process, improved product quality and a greater fraction of the product being in the desired product size range. It is concluded that these results were achieved because the lignite helped to control the granule size in the dryer. Furthermore neither Salmonella spp or E coli were detected in the dried samples. Tests on spontaneous combustion show that this risk is increased in proportion to the amount of lignite used as a drying aid. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.
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The distribution of trace elements in Turkish lignites in Western Anatolia and the Thrace Basin
DOE Office of Scientific and Technical Information (OSTI.GOV)
Palmer, C.A.; Tuncali, E.; Finkelman, R.
1999-07-01
The United States Geological Survey (USGS) and the General Directorate of Mineral Research and Exploration in Turkey (Maden Tetkik ve Arama:MTA) are working together to provide a more complete understanding of the chemical properties of lignites from major Turkish lignite producing areas. The project is a part of the USGS effort to produce an international coal database and is part of the ``Technological and Chemical properties of Turkish Lignite Inventory Project'' being conducted by the MTA General Directorate. The lignites in Turkey formed in several different depositional environments at different geologic times and have differing chemical properties. The Eocene lignitesmore » are limited to northern Turkey. Oligocene lignites, in the Trace Basin of northwestern Turkey, are intercalated with marine sediments. Miocene lignites are generally located in western Turkey. These coal deposits have relatively abundant reserves, with limnic characteristics. The Pliocene-Pleistocene lignites are found in the eastern part of Turkey. Most of these lignites have low calorific values, high moisture and high ash contents. The majority of the lignite extraction is worked in open-pit mines. Turkish lignite production is used mainly by power plants; small amounts are used by households and in industry. All the samples in this study were collected as channel samples of the beds. Analyses of 71 coal samples (mostly lignites) have been completed for 54 elements using various analytical techniques including inductively coupled plasma emission and mass spectrometry, instrumental neutron activation analysis and various single element techniques. Many of these lignites have elemental concentrations similar to those of US lignites. However, maximum or mean concentrations of B, Cr, Cs, Ni, As, Br, Sb, Cs and U in Turkey were higher than the corresponding maximum or mean found in either of the Fort Union or Gulf Coast basins, the two most productive lignite basins in the U.S.« less
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Zhang, Lei; Li, Bao; Xia, Yangchao; Liu, Shengyu
2017-09-01
Lignite is an important and useful fossil fuel in the world and the strong hydrophilicity of it limits its applications. Surfactant adsorption on lignite is an effective way to make it hydrophobic. In this work, aiming to examine the effect of the degree of ethoxylation on the adsorption behavior of dodecyl poly ethoxylated surfactants on lignite and the wettability modification of modified lignite by surfactant adsorption, different combined systems formed by surfactants, water and a model surface of Wender lignite have been studied using molecular dynamics simulation. The adsorption configurations vary with the degree of ethoxylation. At the same adsorption amounts, increasing the degree of ethoxylation can make the adsorption layer more compactness and bring stronger adsorption strength. The results of binding energy and its components show that the adsorption of alkyl polyoxyethylene ethers surfactant on lignite is physically adsorbed rather than electrostatically or chemisorbed. Meanwhile, van der Waals interaction plays a dominant role in the adsorption. The addition of surfactant could reduce the possibility of the interaction between water and lignite. Compared to the original lignite, the interaction between them is weakened after surfactant adsorption in water/surfactant/lignite system, thus strengthening the hydrophobicity of lignite. Similar to the adsorption strength, hydrophobicity of modified lignite increases with the increase of the degree of ethoxylation. The lignite surface properties are changed due to surfactant adsorption by analyzing the compositions of interaction energy and the change of hydrogen bonds. Copyright © 2017 Elsevier Inc. All rights reserved.
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Lignite pellets and methods of agglomerating or pelletizing
Baker, Albert F.; Blaustein, Eric W.; Deurbrouck, Albert W.; Garvin, John P.; McKeever, Robert E.
1981-01-01
The specification discloses lignite pellets which are relatively hard, dust resistant, of generally uniform size and free from spontaneous ignition and general degradation. Also disclosed are methods for making such pellets which involve crushing as mined lignite, mixing said lignite with a binder such as asphalt, forming the lignite binder mixture into pellets, and drying the pellets.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Yen, T.F.
1985-01-01
Potassium permanganate and sodium hypochlorite oxidation of lignitic coal were performed. Ion chromatography of low molecular weight carboxylic acids - oxalic acid, formic acid, and acetic acid - produced by potassium permanganate and sodium hypochlorite oxidation was executed. Oxalic acid was found to be the most predominant low molecular weight species. It was estimated that about 10% of the carbon present in the chemical structure of lignite was converted to oxalic acid by sodium hypochlorite oxidation. Ion chromatography analysis showed that about 43% of the lignite carbon was converted to carbon dioxide in all experiments. Biological degradation of lignite bymore » P. versicolor, a white-rot fungus, on lignite/agar and lignite slurry was attempted. Apparently, P. versicolor is capable of growing on lignite slurry. Acclimation of P. versicolor to lignite was proceeded. Biochemical reaction test for laccase production of P. versicolor was performed and found to be positive. 15 refs., 5 figs., 6 tabs.« less
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Tsikritzis, L I; Fotakis, M; Tzimkas, N; Kolovos, N; Tsikritzi, R
2008-02-01
The distribution and correlation of six natural nuclides in the West Macedonia Lignite Center, Northern Greece were studied. Fifty-five samples of lignite, aged from 1.8 to 5 million years, and corresponding steriles, beds of marls, clays and sands alternating with the lignite, were collected perpendicular to the mine benches and measured spectroscopically. The mean concentrations of (238)U and (226)Ra in lignites were found to be higher than that in steriles since these nuclides are associated with the organic material of lignite, whereas (238)U/(226)Ra equilibrium was not observed in either lignites or steriles. Finally, the ratio (226)Ra/(228)Ra in lignites was approximately double of that in steriles, confirming the affinity of the (238)U series with the coal matrix in contrast to the (232)Th series. No correlation was found between radionuclide concentrations and the depth of the sample, nor with the ash content of lignite.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kirhan, S.; Inaner, H.; Nakoman, E.
This study focuses on some lignite properties and calculation of lignite reserves with two classical (isopach and polygon) methods in the Aydin-Sahinali field, Turkey, which is located in the western Turkey. This field has been mined by a private coal company since 1960 by open-cast and mainly underground mining methods. The producing lignites are consumed in domestic heating and industrial factories around Aydin. The metamorphic rocks of Palaezoic age form the basement of the coal field. The lignite-bearing unit of Miocene age, from bottom to the top, consists mainly of pebblestone, lignite and clayey lignite, siltstone with sandstone lenses, whitemore » colored claystone, clayey limestone and silisified limestone lenses. This unit in the lignite field was unconformably overlain by Pliocene unconsolidated sands and gravels. Three hundred seventy-three borehole data have been evaluated, and this study shows that a relatively thick and lateral extensive lignite seam has a mineable thickness of 1.6-14.4 m. The core samples from boreholes in panels in the lignite field indicate that the coal seam, on an as-received basis, contains high moisture contents (17.95-23.45%, average), high ash yields (16.30-26.03%, average), relatively high net calorific values (3,281-3,854 kcal/kg, average), and low total sulfur contents (1.00-1.22%, average). The remaining lignite potential in the Aydin-Sahinali lignite field was calculated as a 4.7 Mt of measured and a 2.9 Mt of mineable lignite-reserves.« less
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Sustainable Mining Land Use for Lignite Based Energy Projects
NASA Astrophysics Data System (ADS)
Dudek, Michal; Krysa, Zbigniew
2017-12-01
This research aims to discuss complex lignite based energy projects economic viability and its impact on sustainable land use with respect to project risk and uncertainty, economics, optimisation (e.g. Lerchs and Grossmann) and importance of lignite as fuel that may be expressed in situ as deposit of energy. Sensitivity analysis and simulation consist of estimated variable land acquisition costs, geostatistics, 3D deposit block modelling, electricity price considered as project product price, power station efficiency and power station lignite processing unit cost, CO2 allowance costs, mining unit cost and also lignite availability treated as lignite reserves kriging estimation error. Investigated parameters have nonlinear influence on results so that economically viable amount of lignite in optimal pit varies having also nonlinear impact on land area required for mining operation.
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NASA Astrophysics Data System (ADS)
Cehlár, Michal; Rybár, Radim; Pinka, Ján; Haxhiu, Lorik; Beer, Martin
2013-06-01
This review describes the possibility of development a new lignite deposit in northern Kosovo lignite basin - Sibovc. Analysis of the initial state briefly evaluates Kosovo energy sector, geomorphological conditions and quality of lignite from Sibovc deposit. With using Dataminesoft it was created geological model and approximate calculation of lignite reserves in the deposit. The data obtained from Dataminesoft were used as starting points of the financial analysis of project. The result of the analysis is exactly describe the qualitative and quantitative characteristics of deposit Sibovc compared to other deposits in the area and creating of geological model with productive horizons deposit of lignite. Based on these data lignite deposit Sibovc was classified, according to the classification of deposits the UN, as economical. W pracy tej omówiono możliwości udostępnienia nowego obszaru wybierania złoża węgla brunatnego (lignitu) w północnej części zagłębia węgla brunatnego Sibovc w Kosowie. W analizie stanu początkowego krótko scharakteryzowano sektor energetyczny Kosowa, warunki geo-morfologiczne oraz parametry jakościowe węgla brunatnego z zagłębia Sibovc. Przy pomocy pakietu Dataminesoft stworzono model geologiczny i przeprowadzono przybliżone obliczenia zasobów węgla brunatnego w złożu. Dane uzyskane przy zastosowaniu pakietu Dataminesoft zostały następnie wykorzystane jako dane wejściowe do analizy finansowej przedsięwzięcia. Na podstawie wyników analizy uzyskuje się jakościową i ilościową charakterystykę złoża w odniesieniu do pozostałych złóż w regionie. Opracowano model geologiczny ze szczegółowym wskazaniem poziomów wybierania lignitu. W oparciu o te dane dokonano klasyfikacji złoża węgla brunatnego (lignitu) w Sibovc zgodnie z międzynarodowymi zasadami klasyfikacji wykazując, że złoże będzie ekonomiczne.
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Chemical investigations of aquifers affected by pyrite oxidation in the Bitterfeld lignite district.
Grützmacher, G; Hindel, R; Kantor, W; Wimmer, R
2001-01-01
In a large area around the former open-pit lignite mines near Bitterfeld, Germany, groundwater taken from wells was analyzed for the major cations, anions, and trace elements. Quaternary and Tertiary sediments were collected from aquifers exposed on the sides of the pits and from boreholes outside the mines and analyzed for major and trace elements, as well as for carbonate, pyritic sulfur and total organic carbon. The pH and electrical conductivity of the sediments in suspension were measured. Significant differences were determined between the Tertiary sediments of the aquifers that were exposed to atmospheric oxygen during the lowering of the groundwater table and those outside the cone of depression. The greatest differences were found in the pyrite content, the pH values, and the electrical conductivity. In order to map the degree to which the mining of the lignite has affected the quality of the groundwater in the study area, the water samples were divided into six classes on the basis of their sulfate content. The neutralization potential was calculated to estimate the potential for acidification. Prediction of future groundwater quality is based on both (i) the present composition of the groundwater, surface water, and Quaternary and Tertiary aquifer sediments and (ii) the present and future groundwater flow directions. These studies have shown which parameters are important for future groundwater monitoring.
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Goksel, Mehmet A.
1983-11-01
Lignite is formed into high strength pellets having a calorific value of at least 9,500 Btu/lb by blending a sufficient amount of an aqueous base bituminous emulsion with finely-divided raw lignite containing its inherent moisture to form a moistened green mixture containing at least 3 weight % of the bituminous material, based on the total dry weight of the solids, pelletizing the green mixture into discrete green pellets of a predetermined average diameter and drying the green pellets to a predetermined moisture content, preferrably no less than about 5 weight %. Lignite char and mixture of raw lignite and lignite char can be formed into high strength pellets in the same general manner.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Yen, T.F.
1985-01-01
Chemical oxidation of lignite by means of hydrogen peroxide - acetic acid was executed. Methanol fractionation of the oxidized product yielded 76.4% methanol solubles, 9.3% methanol insolubles and 11.2% CO/sub 2/. Biodegradation of the methanol fraction by soil bacteria was found to be positive as demonstrated by gel permeation chromatography (GPC). The shift of the average molecular weight throughout biodegradation was estimated to be from 310 g/mole, to 243 g/mole, zero day and four weeks respectively. Biodegradation of lignitic substrates, benzene - methanol fraction (A - 1), aqueous alkaline fraction (A - 2), clean lignite residue (A - 3), rawmore » lignite, and methanol soluble fraction after oxidation, by means of oil - field soil bacteria and Polyporus versicolor ATCC 12679 was attempted. All previous mentioned lignitic substrates yielded positive results for oil-field soil bacteria, while A - 2 fraction and raw lignite yielded positive results for P. versicolor. Unidentified fungi strains, N 1, L 1, and L 2 were also tested on lignitic substrates. Mild growth was observed in these cases.« less
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Biodegradation of photo-oxidized lignite and characterization of the products
NASA Astrophysics Data System (ADS)
Li, Jiantao; Liu, Xiangrong; Yue, Zilin; Zhang, Yaowen
2018-01-01
Biodegradation of photo-oxidized Inner Mongolia lignite by pseudomonas aeruginosa was studied and the degradation percentage reached 56.27%, while the corresponding degradation percentage of the strain degrading raw Inner Mongolia lignite is only 23.16%. The degradation products were characterized. Proximate and ultimate analyses show that the higher oxygen content increased by photo-oxidation pretreatment maybe promoted the degradation process. Ultraviolet spectroscopy (UV) analysis of the liquid product reveals that it contains unsaturated structures and aromatic rings are the main structure units. Gas chromatography-mass spectrometry (GC-MS) analysis indicates that the main components of the ethyl acetate extracts are low molecular weight organic compounds, such as ketones, acids, hydrocarbons, esters and alcohols. Infrared spectroscopy (IR) analysis of raw lignite, photo-oxidized lignite and residual lignite demonstrates that the absorption peaks of functional groups in residual lignite disappeared or weakened obviously. Scanning electron microscopy (SEM) analysis manifests that small holes appear in photo-oxidized lignite surface, which may be promote the degradation process and this is only from the physical morphology aspects, so it can be inferred from the tests and analyses results that the more important reason of the high degradation percentage is mostly that the photo-oxidation pretreatment changes the chemical structures of lignite.
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Degradation of Coal by the Fungi Polyporus versicolor and Poria monticola
Cohen, Martin S.; Gabriele, Peter D.
1982-01-01
We report that two species of basidiomycete fungi (Polyporus versicolor and Poria monticola) grow in minimal liquid or solid medium when supplemented with crushed lignite coal. The fungi also grow directly on crushed lignite coal. The growth of both fungi was observed qualitatively as the production and extension of hyphae. No fungal growth occurred in minimal agar medium without coal. The fungi degraded solid lignite coal to a black liquid product which never appeared in cultures unless fungi and coal were present together. Apparently, lignite coal can serve as the principal substrate for the growth of the fungi. Infrared analyses of the liquid products of lignite degradation showed both similarities to and differences from the original lignite. Images PMID:16346060
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Solubilization of Australian lignites by microorganisms
DOE Office of Scientific and Technical Information (OSTI.GOV)
Catcheside, D.E.A.; Mallett, K.J.; Cox, R.E.
1988-01-01
Australia has substantial lignite deposits, particularly in the Latrobe Valley in Victoria where 4.10/sup 10/ tons are accessible with available technologies. The authors have investigated the susceptibility of these coal to solubilization by microorganisms, including species additional to those already identified as active on North American lignites. The data presented here show that acid oxidized lignites from the Latrobe Valley are solubilized by each of seven species of microorganisms previously found to be active on Leonardite and oxidized North American lignites. These are the wood rot fungi: Trametes versicolor, Poria placenta and Phanerochaete chrysosporium, the lignin degrading prokaryote Streptomyces viridosporusmore » and three fungi isolated from lignite in Mississippi: Candida ML-13, Cunninghamelia YML-1 and Penicillium waksmanii.« less
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JV Task 98 - Controlling Mercury Emissions for Utilities Firing Lignites from North America
DOE Office of Scientific and Technical Information (OSTI.GOV)
Steven Benson
2007-06-15
This project compiled and summarized the findings and conclusions of research, development, and demonstration projects on controlling mercury from lignite coals. A significant amount of work has been conducted since 1994 on mercury in lignite, mercury measurement in flue gases, sorbent, sorbent enhancement additives, oxidation agent development, and full-scale demonstration of mercury control technologies. This report is focused on providing the lignite industry with an understanding of mercury issues associated with the combustion of lignite, as well as providing vital information on the methods to control mercury emissions in coal-fired power plants.
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Uranium-bearing lignite in southwestern North Dakota
Moore, George W.; Melin, Robert E.; Kepferle, Roy C.
1954-01-01
Uranium-bearing lignite was mapped and sampled in the Bullion Butte, Sentinel Butte, HT Butte, and Chalky Buttes areas in southwestern North Dakota. The uraniferous lignite occurs at several stratigraphic positions in the Sentinel Butte member of the Fort Union formation of Paleocene age. A total of 261 samples were collected for uranium analysis from 85 localities, Lignite contained as much as 0.045 percent uranium, 10.0 percent ash, and 0.45 percent uranium in the ash was found although the average is lower. Inferred reserves for the four areas examined are estimated to be about 27 million tons of lignite in beds about 2 feet thick and containing more than 3000 tons of uranium. The lignite in beds about 2 feet thick and containing more than 3000 tons of uranium. The lignite averages more than 30 percent ash in the surface samples. The principal factor that seems to influence the uranium content of lignite beds is their stratigraphic position below the overlying rocks of the White River group of Oligocene age. All of the uranium-bearing beds closely underlie the base of the White River group. Although this relationship seems to be the controlling factor, the relative concentration of uranium may be modified by other conditions. Beds enclosed in permeable rocks are more uraniferous than beds in impermeable rocks, and thin beds have higher content of uranium than thick beds. In addition, thick lignite beds commonly have a top=preferential distribution of uranium. These and other factors suggest that the uranium is secondary and this it was introduced by ground water which had leached uranium from volcanic ash in the overlying rocks of the White River group. It is thought that the uranium is held in the lignite as part of a metallo-organic compound.
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Microbial screening test for lignite degradation. Quarterly progress report No. 2, April-June 1985
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yen, T.F.
1985-01-01
Fractionation of lignite was performed by means of: (1) benzene-methanol followed by aqueous alkaline extraction; and (2) benzene followed by methanol-alkaline extraction. The residue obtained by the latter fractionation was oxidized by means of cupric oxide and separated into methanol soluble fraction and methanol insoluble residue. Methanol-alkaline fraction was further divided into methylene chloride extractable portion and methylene chloride non-extractable portion. Fourier Transform Infrared Spectroscopy (FT-IR) was employed to characterize functional groups present in the raw lignite sample, benzene-methanol fraction, aqueous alkaline fraction, lignite residue, and benzene fraction. FT-IR was also used for the analysis of both methylene chloride extractablemore » and non-extracted portions. The following are some functional groups identified by the spectra of the fractions mentioned above: OH, amide, aromatic, CH, CO, C=C, CH/sub 2/, C-CH/sub 3/, SiCH/sub 3/, epoxide, and C-O-C. Both, raw lignite sample and aqueous alkaline fraction produced positive results for P. versicolor growth, whereas benzene-methanol fraction and lignite residue produced negative results. Acclimation of P. versicolor to lignite was accomplished up to 80% lignite and 20% neopeptone and maltose. 10 refs., 9 figs., 6 tabs.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Ward, B.
1985-01-01
Following a month-long start-up period during which the principal investigator traveled to several sites of lignite outcrops to collect samples, efforts were begun to isolate new strains of coal-bioconverting fungal strains. Out of about thirty different organisms isolated from weathered samples of three different types of lignite, three isolates exhibited biosolubilization of the one lignite tested to date. These organisms have not yet been identified but they appear to be new strains of lignite-degrading fungi. We have observed that degree of biosolubilization varies among apparently similar samples of the same lignite. Weathered lignite is more readily solubilized than is previouslymore » unexposed lignite, but even tests on weathered coal have not been consistently repeatable. We have begun experiments designed to identify one or more factors of weathering which render coal more readily attacked by fungi. We hope to establish methods whereby consistently repeatable assays can be performed on bioconversion of coals. 2 refs., 1 fig., 1 tab.« less
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Liu, Zhengang; Balasubramanian, Rajasekhar
2014-01-01
In the present study, the conversion of fuel-N to HCN and NH3 was investigated during rapid pyrolysis of raw biomass (coconut fiber), its corresponding biochar and their blends with lignite within a temperature range of 600-900°C. The results showed that the raw biomass and the biochar showed totally different nitrogen partitioning between NH3 and HCN. HCN was the dominant nitrogen pollutant from pyrolysis of raw biomass, while for the biochar pyrolysis the yield of NH3 was slightly higher than that of HCN. Synergistic interactions occurred within both raw biomass/lignite and biochar/lignite blends, especially for the biochar/lignite blend, and resulted in reduced yields of HCN and NH3, decreased the total nitrogen percentage retained in the char and promoted harmless N2 formation. These findings suggest that biochar/lignite co-firing for energy production may have the enhanced benefit of reduced emissions of nitrogen pollutants than raw biomass/lignite. Copyright © 2013 Elsevier Ltd. All rights reserved.
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NASA Astrophysics Data System (ADS)
Maurya, A. S.
2016-12-01
FIRST REPORT OF MICROFAUNAL REMAINS FROM LIGNITIC SEQUENCES OF BHAVNAGAR LIGNITE MINE (KHADSALIYA FORMATION), GUJARAT, INDIA: IMPLICATION TO DEPOSITIONAL ENVIRONMENTS AND AGEABHAYANAND SINGH MAURYA1*, SANJAY KUMAR VERMA1, PRAGYA PANDEY11Department of Earth Sciences, Indian Institute of Technology Roorkee, Roorkee Moderately preserved fish otoliths, fish vertebra, bivalves, pteropods, ostracods and foraminifereral remains were recovered from the grey to greenish-grey clays of Khadsaliya Formation, Bhavnagar Lignite Mine (western India) and quantitatively analyzed to understand the depositional environment. The bio-facies assemblage is diverse and dominated by fauna Fishes, Bivalve, Pteropods and with rare occurrences of Ostracoda and Foraminifera. Fish fauna includes otoliths represented by Ambassidarum, Apogonidarum, Percoideorum and Gobiidarum vastani, out of which Gobiidarum vastani is possibly representing Ypresian (early Eocene). The Globanomalina ovalis a smaller planktic foraminifer is known to be a very short ranged species corresponds to Planktic Foranimiferal Zone 5 to 6 (P5-P6) i.e late Thanetian to early Yepresian. Presence of both fresh water (Lepisosteus, Osteoglossidae), fresh water (Cypridopsis) ostracods and shallow marine fauna (Enchodus, Egertonia and Stephanodus) of fish vertebra; (Cardita) bivalve, , marine water (Globanomalina, Eggrella, Pyrulinoides) foraminifer suggests that Bhavnagar lignite mine have an assemblage of admixed fauna and rocks of Khaldsiya formation at Bhavnagar Lignite mine deposited under marine transgressive-regressive cycles. Some of the microfauna from Bhavnagar lignite mine show close affinities with microfaunal assemblages of the Vastan lignite mine of Gujarat, India which is stated to be of Ypresian (early Eocene).
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Organic compounds in water extracts of coal: links to Balkan endemic nephropathy.
Maharaj, S V M; Orem, W H; Tatu, C A; Lerch, H E; Szilagyi, D N
2014-02-01
The Pliocene lignite hypothesis is an environmental hypothesis that has been proposed to explain the etiology of Balkan endemic nephropathy (BEN). Aqueous leaching experiments were conducted on a variety of coal samples in order to simulate groundwater leaching of organic compounds, and to further test the role of the Pliocene lignite hypothesis in the etiology of BEN. Experiments were performed on lignite coal samples from endemic BEN areas in Romania and Serbia, and lignite and bituminous coals from nonendemic regions in Romania and the USA. Room temperature, hot water bath, and Soxhlet aqueous extraction experiments were conducted between 25 and 80 °C, and from 5 to 128 days in duration. A greater number of organic compounds and in higher concentrations were present in all three types of leaching experiments involving endemic area Pliocene lignite samples compared to all other coals examined. A BEN causing molecule or molecules may be among phenols, PAHs, benzenes, and/or lignin degradation compounds. The proposed transport pathway of the Pliocene lignite hypothesis for organic compound exposure from endemic area Pliocene lignite coals to well and spring drinking water, is likely. Aromatic compounds leached by groundwater from Pliocene lignite deposits in the vicinity of endemic BEN areas may play a role in the etiology of the disease. A better understanding of organic compounds leached by groundwater from Pliocene lignite deposits may potentially lead to the identification and implementation of effective strategies for the prevention of exposure to the causative agent(s) for BEN, and in turn, prevention of the disease.
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Harlow C. Landphair
1979-01-01
This paper relates the evolution of an empirical model used to predict public response to scenic quality objectively. The text relates the methods used to develop the visual quality index model, explains the terms used in the equation and briefly illustrates how the model is applied and how it is tested. While the technical application of the model relies heavily on...
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USSR Report, International Affairs
1986-10-07
the comprehensive utilization of coal and devel- opment of improved methods assuring a more effective use of low-quality coals, low- calory lignites...promising trend of the joint activity in this sphere. Thus, cyclone furnaces for burning low-quality fuel and fuel wastes save up to 10-20 per cent of...structure of the developing countries should be refined and made concrete and we should move from studying particular classes and strata to a comprehensive
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Petrography and geochemistry of the San Miguel lignite, Jackson Group (Eocene), south Texas
Warwick, Peter D.; Crowley, Sharon S.; Ruppert, Leslie F.; Pontolillo, James
1996-01-01
The San Miguel lignite deposit (late Eocene, lower Jackson Group) of south Texas consists of four or more thin (generally < 1 m thick) lignite benches that are separated by claystone and mudstone partings. The partings are composed of altered volcanic air-fall ash that has been reworked by tidal or channel processes associated with a back-barrier depositional environment. The purpose of this study is to examine the relationship between the ash yield and the petrographic and geochemical characteristics of the San Miguel lignite as mined. Particular attention is given to 12 of the environmentally sensitive trace elements (As, Be, Cd, Cr, Co, Hg, Mn, Ni, Pb, Sb, Se, and U) that have been identified as possible hazardous air pollutants (HAPs) by the United States Clean Air Act Amendments of 1990. A total of 29 rock and lignite samples were collected and characterized by geochemical and petrographic methods. The major conclusions of the study are as follows: (1) The distribution of Mn is inversely related to the ash yield of the lignite samples. This indicates an organic affinity, or an association with finely disseminated minerals in the lignite that contain this element. (2) On a whole-coal basis, the concentration of the HAPs' element Pb is positively related to ash yield in lignite samples. This indicates an inorganic affinity for Pb. (3) Average whole-coal concentrations of As, Be, Sb, and U in the San Miguel samples are greater than published averages for these elements in other U.S. lignites. (4) The upper and lower lignite benches of the San Miguel deposit are both ash- and algal-rich, indicating that these intervals were probably deposited in wetter conditions than those in which the middle intervals formed. (5) The dominance of the eugelinite maceral subgroup over the huminite subgroup indicates that the San Miguel lignites were subjected to peat-forming conditions (either biogenic or chemical) that enabled degradation of wood cellular material into matrix gels, or that the plants that formed these lignite benches were less woody and more prone to formation of matrix gels. (6) An inertinite-rich layer (top of the B bed) might have formed from widespread oxidation of the San Miguel peat as a result of a volcanic ash fall which was subsequently reworked.
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Active methods of mercury removal from flue gases.
Marczak, Marta; Budzyń, Stanisław; Szczurowski, Jakub; Kogut, Krzysztof; Burmistrz, Piotr
2018-03-23
Due to its adverse impact on health, as well as its global distribution, long atmospheric lifetime and propensity for deposition in the aquatic environment and in living tissue, the US Environmental Protection Agency (US EPA) has classified mercury and its compounds as a severe air quality threat. Such widespread presence of mercury in the environment originates from both natural and anthropogenic sources. Global anthropogenic emission of mercury is evaluated at 2000 Mg year -1 . According to the National Centre for Emissions Management (Pol. KOBiZE) report for 2014, Polish annual mercury emissions amount to approximately 10 Mg. Over 90% of mercury emissions in Poland originate from combustion of coal.The purpose of this paper was to understand mercury behaviour during sub-bituminous coal and lignite combustion for flue gas purification in terms of reduction of emissions by active methods. The average mercury content in Polish sub-bituminous coal and lignite was 103.7 and 443.5 μg kg -1 . The concentration of mercury in flue gases emitted into the atmosphere was 5.3 μg m -3 for sub-bituminous coal and 17.5 μg m -3 for lignite. The study analysed six low-cost sorbents with the average achieved efficiency of mercury removal from 30.6 to 92.9% for sub-bituminous coal and 22.8 to 80.3% for lignite combustion. Also, the effect of coke dust grain size was examined for mercury sorptive properties. The fine fraction of coke dust (CD) adsorbed within 243-277 μg Hg kg -1 , while the largest fraction at only 95 μg Hg kg -1 . The CD fraction < 0.063 mm removed almost 92% of mercury during coal combustion, so the concentration of mercury in flue gas decreased from 5.3 to 0.4 μg Hg m -3 . The same fraction of CD had removed 93% of mercury from lignite flue gas by reducing the concentration of mercury in the flow from 17.6 to 1.2 μg Hg m -3 . The publication also presents the impact of photochemical oxidation of mercury on the effectiveness of Hg vapour removal during combustion of lignite. After physical oxidation of Hg in the flue gas, its effectiveness has increased twofold.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Nurten Vardar; Zehra Yumurtaci
The major gaseous emissions (e.g. sulfur dioxide, nitrogen oxides, carbon dioxide, and carbon monoxide), some various organic emissions (e.g. benzene, toluene and xylenes) and some trace metals (e.g. arsenic, cobalt, chromium, manganese and nickel) generated from lignite-fired power plants in Turkey are estimated. The estimations are made separately for each one of the thirteen plants that produced electricity in 2007, because the lignite-fired thermal plants in Turkey are installed near the regions where the lignite is mined, and characteristics and composition of lignite used in each power plant are quite different from a region to another. Emission factors methodology ismore » used for the estimations. The emission factors obtained from well-known literature are then modified depending on local moisture content of lignite. Emission rates and specific emissions (per MWh) of the pollutants from the plants without electrostatic precipitators and flue-gas desulfurization systems are found to be higher than emissions from the plants having electrostatic precipitators and flue -gas desulfurization systems. Finally a projection for the future emissions due to lignite-based power plants is given. Predicted demand for the increasing generation capacity based on the lignite-fired thermal power plant, from 2008 to 2017 is around 30%. 39 refs., 13 figs., 10 tabs.« less
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The influence of organic substances type on the properties of mineral-organic fertilizers
NASA Astrophysics Data System (ADS)
Huculak-Mä Czka, Marta; Hoffmann, Krystyna; Hoffmann, Józef
2010-05-01
In presented research the lignite coal, peat, poultry droppings and their composts were suggested as a components of mineral-organic fertilizers. Fertility of soil is conditioned by an ability to supply plants with water and nutrients essential to their growth and development. The soil is described as tri-phase system consisting of solid, liquid and gas phase. In solid phase the soil minerals and organic matter can be distinguished. The content of micro-organisms contained in the soil i.e. microfauna and microflora is indispensable for high soil fertility. Nutrients should occur in the forms available for plants in order to obtain high yields of the high quality crops. Organic fertilizing has versatile activity. Increasing contents of humus, providing mineral nutrients included in organic substance and the improvement in physical properties of the soil belong to its main purposes. Due to applying organic fertilizers heavy soils is getting loosen and in consequence become more airy what probably influences stimulation of soil micro-organisms activity. An aqueous as well as sorption capacity of light soils is also increasing, buffer range and the stabilization of the proper level of pH value of the soil, plants are provided with basic macro and micronutrients. Conventional organic fertilizers applied in an arable farms are manure, dung, green manures and composts of different kind. Within compost group the following types can be distinguished: compost from farming, urban wastes, shredded straw, poultry droppings, industrial wastes, bark of coniferous tree etc. Properly developed fertilizer formulas should contain in their composition both mineral as well as organic elements. Such fertilizer should fit its composition to the soil and plant requirements. It should contain organic substance being characterized by a high aqueous and cations sorption capacity, substance undergoing the fast mineralization with the large calcium content. Inorganic substances e.g. bentonites which are used for suspension fertilizers manufacturing meet these requirements as well. In the presented studies lignite coal was applied as a component of mineral-organic preparations. The advantages of lignite coal are positive influence on the soil heat balance and reduction of the temperature fluctuations influence as well as humic acids contents that are extracted during its decomposition improving the soil structure and enrichment with humus substances. The lignite coal used in examinations contained 50 - 60 wt. % of Corg, about 45 cmol/kg Ca, 18.5 cmol/kg Mg and P, K, N in the ppm amount. Unfortunately the fertilizer components included in the lignite coal are rather unavailable for plants. It seems, that progress of lignite coal mineralization and humification can be expressed in the increasing content of humus substances. Humus acids are of great importance for plants on account of their solubility. During examination on the selection of fertilizer components a Corg content was analyzed as a parameter determining the quality of mineral-organic preparations. As the analytical technique for Corg determination particularly a Tiurin method was applied. Apart from lignite coal and peat as the source of organic substance the poultry droppings and compost on their basis were analyzed. Poultry droppings depending on bird species as well as feeding and breeding method are characterized by variable composition. A high pH values and a large content of nitrogen are their distinctive features, sometimes too high on account of plant nutritional requirements, and toxic as well as limiting cropping. Taking environmental protection requirements into consideration as well as on account of proper plants nutrition an appropriate preparation of mineral-organic fertilizer is recommended what can be obtained by applying lignite coal and poultry droppings as components of fertilizer using appropriate proportion. Adapting composted poultry droppings is more beneficial, but requires extra financial outlays. Results obtained from examinations of organic substance and the investigations on the influence of components on plants germination allow for developing valid formulas for mineral-organic fertilizers.
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Less-costly activated carbon for sewage treatment
NASA Technical Reports Server (NTRS)
Ingham, J. D.; Kalvinskas, J. J.; Mueller, W. A.
1977-01-01
Lignite-aided sewage treatment is based on absorption of dissolved pollutants by activated carbon. Settling sludge is removed and dried into cakes that are pyrolyzed with lignites to yield activated carbon. Lignite is less expensive than activated carbon previously used to supplement pyrolysis yield.
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Parks, William Scott
1981-01-01
Lignite in western Tennessee occurs as lenses or beds at various stratigraphic horizons in the Coastal Plain sediments of Late Cretaceous and Tertiary age. The occurrence of this lignite has been known for many decades, but not until the energy crisis was it considered an important energy resource. In recent years, several energy companies have conducted extensive exploration programs in western Tennessee, and tremendous reserves of lignite have been found. From available information, Lauderdale County was selected as one of the counties where strip-mining of lignite will most likely occur. Lignite in this county occurs in the Jackson and Cockfield Formations, undivided, of Tertiary age. The hydrology of the county is known only from regional studies and the collection of some site-specific data. Therefore, in anticipation of the future mining of lignite, a plan is needed for obtaining hydrologic and geologic information to adequately define the hydrologic system before mining begins and to monitor the effects of strip-mining once it is begun. For this planning effort, available hydrologic, geologic, land use, and associated data were located and compiled; a summary description of the surface and shallow subsurface hydrologic system was prepared: the need for additional baseline hydrologic information was outlined; and plans to monitor the effects of strip-mining were proposed. This planning approach, although limited to a county area, has transferability to other Coastal Plain areas under consideration for strip-mining of lignite.
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Texas lignite mining: Groundwater and slope stability control in the nineties and beyond
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lawrence J.
As lignite mining in Texas approaches and exceeds depths of 200 feet below ground level, rising costs demand that innovative mining approaches be used in order to maintain the economic viability of lignite mining. Groundwater and slope stability problems multiply at these depths, resulting in increasing focus on how to control these costs. Dewatering costs are consistently rising for the lignite industry, as deeper mining encounters more and larger saturated sand bodies. These sands require dewatering in order to improve slope stability. Planning and analysis become more important as the number of wells grows beyond what can be managed withmore » a simple {open_quotes}cookie-cutter{close_quotes} approach. Slope stability plays an increasing role in mining concerns as deeper lignite is recovered. Slope stability causes several problems, including loss of lignite, increased rehandle, and hazards to personnel and equipment. Traditional lignite mine planning involved a fairly {open_quotes}generic{close_quotes} pit design with one design highwall angle, one design spoil angle, and little geotechnical evaluation of the deposit. This {open_quotes}one mine-one design{close_quotes} approach, while cost-effective in the past, is now being replaced by a more critical analysis of the design requirements of each area. Geotechnical evaluation plays an increasing role in the planning and operational aspects of lignite mining. Laboratory core sample test results can be used for slope stability modeling, in order to obtain more accurate design and operational information.« less
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Eocene Yegua Formation (Claiborne group) and Jackson group lignite deposits of Texas
Hook, Robert W.; Warwick, Peter D.; Swanson, Sharon M.; Hackley, Paul C.; Warwick, Peter D.; Karlsen, Alexander K.; Merrill, Matthew D.; Valentine, Brett J.
2011-01-01
The lignite deposits within the upper Eocene Yegua Formation (Claiborne Group) and the overlying Jackson Group are among the coal resources that were not quantitatively assessed as part of the U.S. Geological Survey's (USGS) National Coal Resource Assessment (NCRA) program in the Gulf Coastal Plain coal province. In the past, these lignite-bearing stratigraphic units often have been evaluated together because of their geographic and stratigraphic proximity (Fisher, 1963; Kaiser, 1974; Kaiser et al., 1980; Jackson and Garner, 1982; Kaiser, 1996) (Figures 1, 2). The term “Yegua-Jackson trend“ is used informally herein for the lignite-bearing outcrops of these Late Eocene deposits in Texas. Lignite beds in the Yegua-Jackson trend generally are higher both in ash yield and sulfur content than those of the underlying Wilcox Group (Figure 2). Recent studies (Senkayi et al., 1987; Ruppert et al., 1994; Warwick et al., 1996, 1997) have shown that some lignite beds within the Yegua-Jackson trend contain partings of volcanic ash and host elevated levels of trace elements that have been identified as potentially hazardous air pollutants (HAPs) in the United States Clean Air Amendments of 1990. Lignite beds within the Yegua Formation are thin (less than or equal to 6 ft) and laterally discontinuous in comparison with most Wilcox Group deposits (Ayers, 1989a); in contrast, the Jackson Group lignite beds range up to 12 ft in total thickness and are relatively continuous laterally, extending nearly 32 mi along strike.
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Preliminary report on near-surface lignite occurrences, Cleveland County, Arkansas
Heermann, Stephen E.
1983-01-01
Four cross sections were constructed from lithologic descriptions of 43 drill holes in Cleveland County, Ark., in order to illustrate the occurrence of lignite and to relate the lignite beds to the regional stratigraphic framework. Of 43 holes drilled, 8 contained beds of lignite, but only two had beds greater than 30 in. thick. These beds are apparently lenticular and are restricted to the upper 60 ft. of the Cockfield Formation of the Claiborne Group of Middle Eocene age. The Cockfield Formation is at or near the surface west of the Saline River.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Elbeyli, I.Y.; Palantoken, A.; Piskin, S.
2006-08-15
Microbial coal liquefaction/solubilization of three low-rank Turkish coals (Bursa-Kestelek, Kutahya-Seyitomer and Mugla-Yatagan lignite) was attempted by using a white-rot fungus (Phanerochaete chrysosporium DSM No. 6909); chemical compositions of the products were investigated. The lignite samples were oxidized by nitric acid under moderate conditions and then oxidized samples were placed on the agar medium of Phanerochaete chrysosporium. FTIR spectra of raw lignites, oxidized lignites and liquid products were recorded, and the acetone-soluble fractions of these samples were identified by GC-MS technique. Results show that the fungus affects the nitro and carboxyl/carbonyl groups in oxidized lignite sample, the liquid products obtained bymore » microbial effects are the mixture of water-soluble compounds, and show limited organic solubility.« less
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Li, Yeqing; Yan, Fang; Li, Tao; Zhou, Ying; Jiang, Hao; Qian, Mingyu; Xu, Quan
2018-02-01
In this study, an integrated process was developed to produce methane and high-quality bio-briquette (BB) using corn straw (CS) through high-solid anaerobic digestion (HS-AD). CS was anaerobic digested by using a leach bed reactor at four leachate recirculation strategies. After digesting for 28 days, highest methane yield of 179.6 mL/g-VS, which was corresponded to energy production of 5.55 MJ/kg-CS, was obtained at a higher initial recirculation rate of 32 L-leachate per day. Compared with bio-briquette manufactured from raw CS and lignite, the compressive, immersion and falling strength properties of bio-briquette made from AD-treated CS (solid digestate) and lignite were significantly improved. A preferred BB can be obtained with side compressive strength of 863.8 ± 10.8 N and calorific value of 20.21 MJ/kg-BB. The finding of this study indicated that the integrated process could be an alternative way to produce methane and high-quality BB with CS. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Numerical analysis of single and multiple particles of Belchatow lignite dried in superheated steam
NASA Astrophysics Data System (ADS)
Zakrzewski, Marcin; Sciazko, Anna; Komatsu, Yosuke; Akiyama, Taro; Hashimoto, Akira; Kaneko, Shozo; Kimijima, Shinji; Szmyd, Janusz S.; Kobayashi, Yoshinori
2018-03-01
Low production costs have contributed to the important role of lignite in the energy mixes of numerous countries worldwide. High moisture content, though, diminishes the applicability of lignite in power generation. Superheated steam drying is a prospective method of raising the calorific value of this fuel. This study describes the numerical model of superheated steam drying of lignite from the Belchatow mine in Poland in two aspects: single and multi-particle. The experimental investigation preceded the numerical analysis and provided the necessary data for the preparation and verification of the model. Spheres of 2.5 to 30 mm in diameter were exposed to the drying medium at the temperature range of 110 to 170 °C. The drying kinetics were described in the form of moisture content, drying rate and temperature profile curves against time. Basic coal properties, such as density or specific heat, as well as the mechanisms of heat and mass transfer in the particular stages of the process laid the foundations for the model construction. The model illustrated the drying behavior of a single particle in the entire range of steam temperature as well as the sample diameter. Furthermore, the numerical analyses of coal batches containing particles of various sizes were conducted to reflect the operating conditions of the dryer. They were followed by deliberation on the calorific value improvement achieved by drying, in terms of coal ingredients, power plant efficiency and dryer input composition. The initial period of drying was found crucial for upgrading the quality of coal. The accuracy of the model is capable of further improvement regarding the process parameters.
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Development and demonstration of a lignite-pelletizing process. Phase II report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1980-01-01
The current work began with scale-up of laboratory equipment to commercial size equipment. For this purpose, BCI used an existing pilot plant that had been assembled to pelletize and indurate taconite ore. BCI determined therewith that lignite pellets can be produced continuously on a pilot scale using the basic process developed in the laboratory. The resulting pellets were found to be similar to the laboratory pellets at equivalent binder compositions. Tests of product made during a 5-ton test run are reported. A 50-ton demonstration test run was made with the pilot plant. Pellet production was sustained for a two-week period.more » The lignite pelletizing process has, therefore, been developed to the point of demonstration in a 50-ton test. BCI has completed and cost estimated a conceptually designed 4000 TPD facility. BCI believes it has demonstrated a technically feasible process to agglomerate lignite by using an asphalt emulsion binder. Product quality is promising. Capital and operating costs appear acceptable to justify continuing support and development. The next step should focus on three areas: production development, process refinement, and cost reduction. For further development, BCI recommends consideration of a 5 to 10 ton/h pilot plant or a 20 to 40 ton/h module of a full sized plant, the lower first cost of the former being offset by the ability to incorporate the latter into a future production unit. Other specific recommendations are made for future study that could lead to process and cost improvements: Binder Formulation, disc Sizing, Drier Bed Depth, and Mixing Approach. Pellet use other than power plant fuel is considered.« less
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Comparison of artificial maturation of lignite in hydrous and nonhydrous conditions
Behar, F.; Lewan, M.D.; Lorant, F.; Vandenbroucke, M.
2003-01-01
The objectives of the study are to compare product compositions and yields generated from lignite artificially matured by open nonhydrous pyrolysis, closed nonhydrous pyrolysis, and hydrous pyrolysis. The pyrolysis products were fractionated into CO2, H2O, CH4, C2-C5, C8-C14, C14+ saturates, C14+ aromatics and NSOs (resins+asphaltenes). All three methods generated high and similar quantities of water during pyrolysis that ranged between 14.6 and 15.2 wt.% of the original lignite. As a result of this high water content generated by the lignite, the experiments with no added water are referred to as nonhydrous rather than anhydrous. Rock-Eval pyrolysis and elemental analyses were conducted on the recovered lignite after solvent extraction to determine their residual hydrocarbon generation potential and to plot their position in a van Krevelen diagram, respectively. Residual lignite from the closed nonhydrous and hydrous experiments showed relationships between vitrinite reflectance (%Ro) values and atomic H/C ratios that occurred within the fields observed for natural maturation of coal. Although no significant differences in the atomic H/C ratios were observed between closed nonhydrous and hydrous pyrolysis, the vitrinite reflectance values were on the average 0.2% Ro lower in the residual lignite from the nonhydrous experiments. The remaining hydrocarbon generation potential as determined by Rock-Eval pyrolysis of the residual lignite showed that the nonhydrous residuals had on the average 16 mg more hydrocarbon potential per gram of original lignite than the hydrous residuals. This suggests there is a better release of the pyrolysis products from the lignite network in the hydrous experiments once generation occurs. For gas generation, at maximum yields, open nonhydrous pyrolysis generates the most hydrocarbon gas (21.0 mg/g original lignite), which is 20% more than closed nonhydrous pyrolysis and 29% more than hydrous pyrolysis. Closed nonhydrous pyrolysis generates on the average 14% more gas than hydrous pyrolysis, but the proportionality of the generated hydrocarbon gases is essentially the same for both pyrolysis methods. At maximum yields, CO2 generation is greatest in hydrous pyrolysis (99.5 mg/g original lignite), with yields being 37 percent higher than closed nonhydrous pyrolysis and 26% higher than open nonhydrous pyrolysis. The maximum yields of C14+ products are highest and similar for open nonhydrous pyrolysis and hydrous pyrolysis (125.6 and 125.9 mg/g lignite, respectively), and are more than 70% higher than closed nonhydrous pyrolysis. This difference in the maximum yields of C14+ products can be explained by differences in the proportionality between either cracking reactions that result in liquid product and char formation or trapping of generated products within the coal network (cross-linking reactions). Maximum yields of C14+ aliphatics from hydrous experiments may not have been attained, but the maximums that were observed and their GC traces are similar for the three pyrolysis systems.
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Leaching characteristics of fly ash from thermal power plants of Soma and Tuncbilek, Turkey.
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.
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Effects of lignite application on ammonia and nitrous oxide emissions from cattle pens.
Sun, Jianlei; Bai, Mei; Shen, Jianlin; Griffith, David W T; Denmead, Owen T; Hill, Julian; Lam, Shu Kee; Mosier, Arvin R; Chen, Deli
2016-09-15
Beef cattle feedlots are a major source of ammonia (NH3) emissions from livestock industries. We investigated the effects of lignite surface applications on NH3 and nitrous oxide (N2O) emissions from beef cattle feedlot pens. Two rates of lignite, 3 and 6kgm(-2), were tested in the treatment pen. No lignite was applied in the control pen. Twenty-four Black Angus steers were fed identical commercial rations in each pen. We measured NH3 and N2O concentrations continuously from 4th Sep to 13th Nov 2014 using Quantum Cascade Laser (QCL) NH3 analysers and a closed-path Fourier Transform Infrared Spectroscopy analyser (CP-FTIR) in conjunction with the integrated horizontal flux method to calculate NH3 and N2O fluxes. During the feeding period, 16 and 26% of the excreted nitrogen (N) (240gNhead(-1)day(-1)) was lost via NH3 volatilization from the control pen, while lignite application decreased NH3 volatilization to 12 and 18% of the excreted N, for Phase 1 and Phase 2, respectively. Compared to the control pen, lignite application decreased NH3 emissions by approximately 30%. Nitrous oxide emissions from the cattle pens were small, 0.10 and 0.14gN2O-Nhead(-1)day(-1) (<0.1% of excreted N) for the control pen, for Phase 1 and Phase 2, respectively. Lignite application increased direct N2O emissions by 40 and 57%, to 0.14 and 0.22gN2O-Nhead(-1)day(-1), for Phase 1 and Phase 2, respectively. The increase in N2O emissions resulting from lignite application was counteracted by the lower indirect N2O emission due to decreased NH3 volatilization. Using 1% as a default emission factor of deposited NH3 for indirect N2O emissions, the application of lignite decreased total N2O emissions. Copyright © 2016 Elsevier B.V. All rights reserved.
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Hasani, F; Shala, F; Xhixha, G; Xhixha, M K; Hodolli, G; Kadiri, S; Bylyku, E; Cfarku, F
2014-12-01
The energy production in Kosovo depends primarily on lignite-fired power plants. During coal combustion, huge amounts of fly ash and bottom ash are generated, which may result in enriched natural radionuclides; therefore, these radionuclides need to be investigated to identify the possible processes that may lead to the radiological exposure of workers and the local population. Lignite samples and NORMs of fly ash and bottom ash generated in lignite-fired power plants in Kosovo are analyzed using a gamma-ray spectrometry method for the activity concentration of natural radionuclides. The average activity concentrations of (40)K, (226)Ra and (232)Th in lignite are found to be 36 ± 8 Bq kg(-1), 9 ± 1 Bq kg(-1) and 9 ± 3 Bq kg(-1), respectively. Indications on the occurrence and geochemical behavior of uranium in the lignite matrix are suggested. The activity concentrations of natural radionuclides in fly ash and bottom ash samples are found to be concentrated from 3 to 5 times that of the feeding lignite. The external gamma-ray absorbed dose rate and the activity concentration index are calculated to assess the radiological hazard arising from ash disposal and recycling in the cement industry. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Millennial-scale Climate Variations Recorded As Far Back As The Early Pliocene
NASA Astrophysics Data System (ADS)
Steenbrink, J.; Hilgen, F. J.; Lourens, L. J.
Quaternary climate proxy records show compelling evidence for climate variability on time scales of a few thousand years. The causes for these millennial-scale or sub- Milankovitch cycles are yet poorly understood, not in the least due to the complex feedback mechanisms of large ice-sheets during the Quaternary. We present evidence of millennial-scale climate variability in Early Pliocene lacustrine sediments from the intramontane Ptolemais Basin in northwestern Greece. The sediments are well ex- posed in a series of open-pit lignite mines and exhibit a distinct m-scale sedimentary cyclicity of alternating lignites and lacustrine marl beds that result from precession- induced variations in climate. A higher-frequency cyclicity is particular prominent within the marl segment of individual cycles. A stratigraphic interval of~115 kyr, cov- ering five precession-induced sedimentary cycles, was studied in nine parallel sections from two quarries located several km apart. Colour reflectance records were used to quantify the within-cycle variability and to determine its lateral continuity. Much of the within-cycle variability could be correlated between the parallel sections, even in fine detail, which suggests that these changes reflect basin-wide variations in environ- mental conditions related to (regional) climate fluctuations. Interbedded volcanic ash beds demonstrate the synchronicity of these fluctuations and spectral analysis of the reflectance time series shows a significant concentration of variability at periods of ~11,~5.5 and~2 kyr. Their occurrence at times before the intensification of the North- ern Hemisphere glaciation suggests that they cannot solely have resulted from internal ice-sheet dynamics. Possible candidates include harmonics or combination tones of the main orbital cycles, variations in solar output or periodic motions of the Earth and moon.
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-10-24
... Environmental Impact Statement for Surface Coal and Lignite Mining in the State of Texas AGENCY: Department of..., indirect, and cumulative effects associated with a decision to develop and assess data and information with... responsibility. These coal and lignite mining activities may eventually require authorization from the USACE...
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Ali Sinag; Melike Sungur; Muammer Canel
Copyrolysis of a Turkish lignite with low-density polyethylene (LDPE) is conducted in a tubular reactor. The effect of experimental conditions (temperature of 400-700{sup o}C, catalyst, LDPE contents of the mixture are 33, 50, and 67 wt %) on the formation of tar, gas, and char and their effects on the formation of phenol are investigated. The catalysts used are red mud (which is a waste product of an aluminum factory in Turkey), zeolite (Linde type A (LTA)), and K{sub 2}CO{sub 3}. Tar evolution is determined to be increased significantly by increasing the LDPE content of the coal-LDPE mixture during themore » pyrolysis. The effect of adding LDPE to the coal on the gas generation is not remarkable. An increase in temperature leads to increased gas yields. Phenol and phenol derivatives are the obstacles for the complete conversion of lignite to tar and gas. To investigate this negative effect of phenols on the yields, the phenols found in tar from coal pyrolysis are detected by gas chromatography-mass spectroscopy (GC-MS), and it is observed that phenolic structures detected in the tar obtained by individual pyrolysis of coal are dramatically decreased by adding polymer to the coal. The use of catalysts during the copyrolysis procedure leads to improved gas generation. The possible reasons of these variations are discussed. A remarkable synergetic effect between lignite and LDPE on the tar yields is also observed. 21 refs., 8 figs., 4 tabs.« less
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Denson, N.M.; Bachman, G.O.; Zeller, H.D.
1954-01-01
the original White River and Arikaree sediments. Individual maps showing the extent, thickness, and variations in mineral content of the important deposits in the Table Mountain, Cave Hills, Slim Buttes, Lodgepole, and Medicine Pole areas are included. Conditions controlling the concentration of uranium are described and their application as guides to finding additional reserves by the presently held concepts are explained and illustrated.
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Long term contracts, expansion, innovation and stability: North Dakota's lignite mines thrive
DOE Office of Scientific and Technical Information (OSTI.GOV)
Buchsbaum, L.
2009-08-15
North Dakota's lignite coal industry is mainly located in three countries in the central part of the state. Its large surface lignite mines are tied through long-term (20-40 years) contracts to power plants. The article talks about operations at three of the most productive mines - the Freedom mine, Falkirk mine and Center Mine. 4 figs.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
F. Karacan; T. Torul
2007-08-15
The effect of the power of ultraviolet (UV) irradiation on the tetrahydrofuran (THF) solubles yield (the total soluble product) and the soluble product distribution of the dissolution of Turkish lignites (Beypazari and Tuncbilek lignite) in tetralin at ambient temperatures has been investigated. The lignite samples were exposed to UV irradiation for 1, 2, 3, 5, and 10 days in the power of irradiation ranging from 0 to 180 W at 60 W intervals. The yields of THF solubles and oils increased with increasing irradiation power and time. The optimum irradiation power depends on the irradiation time to obtain the highestmore » degradation products. However, the yield of degradation products depends also on the lignite type. The largest fraction obtained from lignites by photochemical energy is oil. While the yields of THF solubles and oils sharply increased with irradiation power at longer reaction times, the yields of asphaltenes (AS) slightly decreased. Increasing oil yields is relatively larger when AS yields tend to decrease. These trends of AS and oil yields are ascribable to conversion of AS to oils at higher power. Small changes were observed in the PAS yields under all conditions. 27 refs., 5 figs., 1 tab.« less
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Drosos, Marios; Leenheer, Jerry A; Avgeropoulos, Apostolos; Deligiannakis, Yiannis
2014-03-01
A fractionation technique, combining dialysis removal of metal and ash components with hydrofluoric acid and pH 10 citrate buffer followed by chromatography of dialysis permeate on XAD-8 resin at decreasing pH values, has been applied to lignite humic acid (lignite-HA) and soil humic acid (soil-HA). H-binding data and non ideal competitive adsorption-Donnan model parameters were obtained for the HA fractions by theoretical analysis of H-binding data which reveal a significant increase of the carboxyl and the phenolic charge for the lignite-HA fractions vs. the parental lignite humic acid (LParentalHA). The fractionated lignite-HA material consisted mainly of permeate fractions, some of which were fulvic acid-like. The fractionated soil-HA material consisted mainly of large macromolecular structures that did not permeate the dialysis membrane during deashing. Chargeable groups had comparable concentrations in soil-HA fractions and parental soil humic acid (SParentalHA), indicating minimal interference of ash components with carboxyl and phenolic (and/or enolic) groups. Fractionation of HA, combined with theoretical analysis of H-binding, can distinguish the supramolecular vs. macromolecular nature of fractions within the same parental HA.
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Tang, Yafu; Wang, Xinying; Yang, Yuechao; Gao, Bin; Wan, Yongshan; Li, Yuncong C; Cheng, Dongdong
2017-07-26
In this work, lignite, a low-grade coal, was modified using the solid-phase activation method with the aid of a Pd/CeO 2 nanoparticle catalyst to improve its pore structure and nutrient absorption. Results indicate that the adsorption ability of the activated lignite to NO 3 - , NH 4 + , H 2 PO 4 - , and K + was significantly higher than that of raw lignite. The activated lignite was successfully combined with the polymeric slow-release fertilizer, which exhibits typical slow-release behavior, to prepare the super large granular activated lignite slow-release fertilizer (SAF). In addition to the slow-release ability, the SAF showed excellent water-retention capabilities. Soil column leaching experiments further confirmed the slow-release characteristics of the SAF with fertilizer nutrient loss greatly reduced in comparison to traditional and slow-release fertilizers. Furthermore, field tests of the SAF in an orchard showed that the novel SAF was better than other tested fertilizers in improve the growth of young apple trees. Findings from this study suggest that the newly developed SAF has great potential to be used in apple cultivation and production systems in the future.
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Drosos, Marios; Leenheer, Jerry A.; Avgeropoulos, Apostolos; Deligiannakis, Yiannis
2014-01-01
A fractionation technique, combining dialysis removal of metal and ash components with hydrofluoric acid and pH 10 citrate buffer followed by chromatography of dialysis permeate on XAD-8 resin at decreasing pH values, has been applied to lignite humic acid (lignite-HA) and soil humic acid (soil-HA). H-binding data and non ideal competitive adsorption-Donnan model parameters were obtained for the HA fractions by theoretical analysis of H-binding data which reveal a significant increase of the carboxyl and the phenolic charge for the lignite-HA fractions vs. the parental lignite humic acid (LParentalHA). The fractionated lignite-HA material consisted mainly of permeate fractions, some of which were fulvic acid-like. The fractionated soil-HA material consisted mainly of large macromolecular structures that did not permeate the dialysis membrane during deashing. Chargeable groups had comparable concentrations in soil-HA fractions and parental soil humic acid (SParentalHA), indicating minimal interference of ash components with carboxyl and phenolic (and/or enolic) groups. Fractionation of HA, combined with theoretical analysis of H-binding, can distinguish the supramolecular vs. macromolecular nature of fractions within the same parental HA.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Gennett, J.A.; Raymond, A.L.
1986-09-01
The floral composition of palynomorph assemblages of Jacksonian Texas lignites is closely linked to depositional systems. Localities on the eastern Gulf coastal plain are included in the late Eocene Fayette delta system, and lignite formation is considered to have occurred in lower deltaic environments. Samples are commonly dominated by grains of Caprifoliipites/Salixpollenites, Momites, or Nyssa, indicating dicotyledonous tree-dominated swamps. Some samples contain abundant Cicatricosspories spores, suggesting marshy, fern-dominated areas. The San Miguel lignite deposit in McMullen County is located on the eastern margin of the south Texas strand-plain/barrier-bar system. Caprifoliipites/Salixpollenites pollen is rare in the San Miguel, and most ofmore » the levels are dominated by small tricolporates such as cupuliferoipollenites and Sapotaceae. Nyssa is locally important. The lignite is considered to have been deposited in a nondeltaic freshwater swamp behind a barrier island. The Miguel Alleman deposit, across the Mexican border in Tamaulipas, is thought to have developed in a lagoonal-estuarine environment. Dinoflagellates such as Wetzeliella are common at some levels, indicating marine conditions. As with San Miguel, small tricolporates and Momipites are common. These assemblages contrast with Sabinian floras. Wilcox Group east Texas lignites were formed in fluvial environments. Betulaceous pollen is common in these coals. Sabinian south Texas lignites formed in marine environments yield dinoflagellates and Chenopodium-type pollen. Chenopods are common in present-day Gulf Coast salt marshes but seem to have been absent from Jackson-age seacoasts.« less
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Mössbauer study of Fe mineralogy with respect to rank, type and Colombian carboniferous zone
NASA Astrophysics Data System (ADS)
Caballero, F. Reyes; Martínez Ovalle, S. A.; Díaz Lagos, M.; Gómez, O. P.; Blandón, A.
2017-11-01
The transmission mode of Fe-57 Mössbauer spectroscopy was used to identify iron bearing minerals and establish relationships between and among these minerals and the ranks and types of various carboniferous zones in Colombia. Maceral and mineral compositions vary significantly among Colombian carboniferous zones. These variations determine some of the final characteristics and potential uses of coal, and therefore significantly contribute to defining coal quality. A comparison of spectroscopy results shows that the thermal maturity of the Colombian coals ranges from lignite to semianthracite. Similarities and differences exist with respect to conventional parameters. The coals of Córdoba and Cauca have higher sulfur contents > 2 % ash contents. Iron bearing minerals identified included pyrite, which was, found everywhere, and illite, ankerite, siderite, iron sulfates were found in particular areas. Coals from Valle del Cauca, Córdoba, Caldas and Santander are characterized by oxidation of pyrite and its transformation into ferrous or ferric sulfate.
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A review of Alabama lignite deposits
Aubourg, Claire E.; Warwick, Peter D.; Karlsen, Alexander K.; Merrill, Matthew D.; Valentine, Brett J.
2011-01-01
This review of Alabama lignite deposits is a part of the U.S. Geological Survey (USGS) National Coal Resource Assessment (NCRA) of the Gulf Coast region (see Ruppert et al., 2002; Dennen, 2009; and other chapters of this publication). Because lignite is not currently mined in Alabama, a detailed assessment of the state was not made, and only a review is presented in this chapter.
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Bioprocessing of lignite coals using reductive microorganisms
DOE Office of Scientific and Technical Information (OSTI.GOV)
Crawford, D.L.
In order to convert lignite coals into liquid fuels, gases or chemical feedstock, the macromolecular structure of the coal must be broken down into low molecular weight fractions prior to further modification. Our research focused on this aspect of coal bioprocessing. We isolated, characterized and studied the lignite coal-depolymerizing organisms Streptomyces viridosporus T7A, Pseudomonas sp. DLC-62, unidentified bacterial strain DLC-BB2 and Gram-positive Bacillus megaterium strain DLC-21. In this research we showed that these bacteria are able to solubilize and depolymerize lignite coals using a combination of biological mechanisms including the excretion of coal solublizing basic chemical metabolites and extracellular coalmore » depolymerizing enzymes.« less
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Crawley, Mark E.; Emerson, Douglas G.
1981-01-01
Lignite beds and abundant discontinuous sandstone beds of the Paleocene Sentinel Butte Member of the Fort Union Formation and sand and gravel beds in the Quarternary glaciofluvial deposits (Antelope Creek aquifer) are the most important aquifers for domestic and livestock water supplies in the West Branch Antelope Creek basin. In the Beulah-Zap lignite, ground water moves from highland area in the west toward the Antelope Creek aquifer. Water levels in the basal Sentinel Butte sandstone appear to be controlled by the level of Lake Sakakawea. In the glaciofluvial deposits of the Antelope Creek aquifer water moves from a ground-water divide northwestward to Lake Sakakawea and southeastward toward the Knife River. Large water-level declines in wells completed in the lignite and shallower aquifers could be expected with mining. The effects probably would be limited to within 1 to 2 miles of an active mine. Surface-runoff duration could be altered by increased infiltration and retention in the reclaimed are and possible temporal extension of base flow could occur. Shallow ground water beneath mine sites would be expected to increase in dissolved solids and locally to contain large sodium and sulfate concentrations. In some locations movement of poor quality water toward the Antelope Creek aquifer would be expected. (USGS)
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Horak, W.F.
1983-01-01
In much of western North Dakota, minable lignite beds and associated sand beds are valuable local aquifers. Strip mining disrupts the aquifers and could significantly impact the local hydrology, imposing hardships on local residents. This comprehensive water-resources study of a 147-square-mile coal area in west-central North Dakota was done to facilitate sound management decisions regarding the suitability of the site for mining. Two strippable lignite beds, identified as the D and E beds, in the lower 250 to 300 feet of the Sentinel Butte Member of the Fort Union Formation underlie much of two small stream basins. The lignites and two closely associated sand deposits are the only consistently occurring aquifers within several hundred feet of the land surface. The D lignite bed underlies nearly the entire study area, but is not water bearing where it is structurally uplifted beneath upland areas. It is, for the most part, marginally confined. The E lignite bed overlies the D bed and is extensively eroded along North Creek in the southern part of the study area. The E bed is either unsaturated or unconfined in most of its area of occurrence. Direction of ground-water flow in both lignite aquifers is largely controlled by topography. Interconnected sand beds deposited as channel fill in braided streams form aquifers between the E and D beds (E-D aquifer) and below the D bed (D-HT aquifer). Both aquifers underlie the central part of the study area and each consists of as much as 100 feet of predominantly fine to medium silty unconsolidated sand. Maximum depth to the top of the aquifers was 200 feet for the E-D aquifer and 320 feet for the D-HT aquifer. The E-D aquifer, where near land surface, is unconfined, whereas the D-HT aquifer is entirely confined. Direction of ground-water flow in the D-HT aquifer is not influenced by the local topography as in the three overlying aquifers.Aquifers also occur at much greater depth beneath the study area in strata of Late Cretaceous and early Tertiary age. The Fox Hills and Tongue River aquifers are most commonly utilized and lie at depths of about 1,700 and 750 feet, respectively. Water in all aquifers beneath the study area is a sodium bicarbonate or sodium sulfate type. Mean dissolved solids in the four aquifers in the Sentinel Butte Member ranged from 1,290 to 1,970 milligrams per liter- Most of the samples were soft water, had low dissolved iron concentration, and were slightly to moderately colored (tan to brown) by dissolved organics. Several samples from the four aquifers had a perceptible hydrogen sulfide odor.North Creek and an unnamed tributary of the Green River drain most of the study area. North Creek flows intermittently during most years, while the Green River tributary flows perennially and has base flow of about 0.2 cubic foot per second. North Creek has predominately a sodium sulfate type water and the Green River tributary has a sodium bicarbonate-sulfate type water. At high flows, the dissolved solids generally are less than 1,000 milligrams per liter, and the water contains greater percentages of calcium and magnesium than at low flow.The impacts of strip mining on the shallow ground-water flow system would be very localized due to the already low water levels and the segmented nature of the flow system. Similarly, water-quality impacts on the ground-water system would be localized. Natural geochemical processes are effective in limiting the severity and lateral spread of chemically enriched waters. Streamflow magnitudes should not be significantly affected by mining activities. Stream quality impacts should be readily manageable by ordinary routing, impoundment, and treatment techniques.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Sckefe, C.R.; Patti, A.F.; Clune, T.S.
2008-07-15
To determine how organic amendments and phosphate fertilizers interact to modify P sorption processes, three phosphate fertilizers were applied to lignite- and compost-amended acid soil and incubated for either 3 or 26 days. The fertilizers applied were potassium dihydrogen phosphate, triple superphosphate, and diammonium phosphate (DAP). After 3 days of incubation, sorption of all three P sources was decreased in the lignite-amended treatments, whereas P sorption was increased in the compost-amended treatments. Increased incubation time (26 days) resulted in significantly decreased P sorption when DAP was added to lignite-amended treatments. Addition of triple superphosphate increased P sorption in lignite- andmore » compost-amended treatments and decreased solution pH compared with DAP application. In addition to the effect of P source, differences in P sorption between the lignite- and compost-amended treatments were driven by differences in solution chemistry, predominantly solution pH and cation dynamics. Soil amendment and fertilizer addition also increased microbial activity in the incubation systems, as measured by carbon dioxide respiration. It is proposed that the combination of lignite and DAP may contribute to decreased P sorption in acid soils, with the positive effects likely caused by both chemical and biological processes, including the formation of soluble organic-metal complexes.« less
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Process Analysis of Lignite Circulating Fluidized Bed Boiler Coupled with Pyrolysis Topping
NASA Astrophysics Data System (ADS)
Wang, Baoqun; Dong, Li; Wang, Yin; Matsuzawa, Y.; Xu, Guangwen
We developed a comprehensive process model in ASPEN Plus to simulate the energy and mass balances of a lignite-fueled atmospheric circulating fluidized bed (CFB) boiler integrated with coal predrying and pyrolysis topping. In this model, it is assumed that the heat from exhausted flue gas was employed for coal predrying, and the sensible heat derived from circulated bed material was used for the pyrolysis topping (endothermic process). The simulation was conducted with respectto the Yunnan Kaiyuan CFB boiler, and two representative lignite coals from Xiao Long Tan (XLT) and Xin Shao (XS) were considered. The result shows that the predrying of coal with the sensible heat of above 363 K from flue gas, the amount of coal consumed in the boiler can be reduced by 3.5% and 5.3% for XLT lignite and XS lignite, respectively. It was also found that integration of pyrolysis topping with the boiler increased the coal consumption of the boiler, and the extent of consumption-increase varies with the yields of tar and gas in the pyrolysis topping process. For agas yield of 5.2% and a tar yield of 5-6%, the consumption of XS lignite increased by about 20% comparing to that in the case without topping.
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He, Meng; Zhang, Wei; Cao, Xiaoqiang; You, Xiaofang; Li, Lin
2018-01-01
Experimental and computational simulation methods are used to investigate the adsorption behavior of the surfactant nonylphenol ethoxylate (NPEO10), which contains 10 ethylene oxide groups, on the lignite surface. The adsorption of NPEO10 on lignite follow a Langmuir-type isotherm. The thermodynamic parameters of the adsorption process show that the whole process is spontaneous. X-ray photoelectron spectroscopic (XPS) analysis indicates that a significant fraction of the oxygen-containing functional groups on the lignitic surface were covered by NPEO10. Molecular dynamics (MD) simulations show that the NPEO10 molecules were found to adsorb at the water-coal interface. Moreover, polar interactions are the main effect in the adsorption process. The density distributions of coal, NPEO10, and water molecules along the Z axis show that the remaining hydrophobic portions of the surfactant extend into the solution, creating a more hydrophobic coal surface that repels water molecules. The negative interaction energy calculated from the density profiles of the head and tail groups along the three spatial directions between the surfactant and the lignitic surface suggest that the adsorption process is spontaneous. The self-diffusion coefficients show that the presence of NPEO10 causes higher water mobility by improving the hydrophobicity of lignite. PMID:29389899
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Ruppert, L.; Finkelman, R.; Boti, E.; Milosavljevic, M.; Tewalt, S.; Simon, N.; Dulong, F.
1996-01-01
Trace element data from 59 Pliocene lignite cores from the lignite field in the Kosovo Basin, southern Serbia, show localized enrichment of Ni and Cr (33-304 ppm and 8-176 ppm, respectively, whole-coal basis). Concentrations of both elements decrease from the western and southern boundaries of the lignite field. Low-temperature ash and polished coal pellets of selected bench and whole-coal samples were analyzed by X-ray diffraction and scanning electron microscopy with energy-dispersive X-ray analyses. These analyses show that most of the Ni and Cr are incorporated in detrital and, to a lesser degree, in authigenic minerals. The Ni- and Cr-bearing detrital minerals include oxides, chromites, serpentine-group minerals and rare mixed-layer clays. Possible authigenic minerals include Ni-Fe sulfates and sulfides. Analyses of three lignite samples by a supercritical fluid extraction technique indicate that some (1-11%) of the Ni is organically bound. Ni- and Cr-bearing oxides, mixed-layer clays, chromites and serpentine-group minerals were also identified in weathered and fresh samples of laterite developed on serpentinized Paleozoic peridotite at the nearby Glavica and C??ikatovo Ni mines. These mines are located along the western and northwestern rim, respectively, of the Kosovo Basin, where Ni contents are highest. The detrital Ni- and Cr-bearing minerals identified in lignite samples from the western part of the Kosovo Basin may have been transported into the paleoswamp by rivers that drained the two Paleocene laterites. Some Ni may have been transported directly into the paleoswamp in solution or, alternatively, Ni may have been leached from detrital minerals by acidic peat water and adsorbed onto organic matter and included into authigenic mineral phases. No minable source of Ni and Cr is known in the southern part of the lignite field; however, the mineral and chemical data from the lignite and associated rocks suggest that such a source area may exist.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Crawford, D.L.
In order to convert lignite coals into liquid fuels, gases or chemical feedstock, the macromolecular structure of the coal must be broken down into low molecular weight fractions prior to further modification. Our research focused on this aspect of coal bioprocessing. We isolated, characterized and studied the lignite coal-depolymerizing organisms Streptomyces viridosporus T7A, Pseudomonas sp. DLC-62, unidentified bacterial strain DLC-BB2 and Gram-positive Bacillus megaterium strain DLC-21. In this research we showed that these bacteria are able to solubilize and depolymerize lignite coals using a combination of biological mechanisms including the excretion of coal solublizing basic chemical metabolites and extracellular coalmore » depolymerizing enzymes.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Yen, T.F.
1985-01-01
Degradation of Beulah std No. 3 lignite was carried out by means of cupric oxidation, modified-autoclaved-cupric oxidation, sodium dichromate oxidation, and also by biological methods. Assessment of the yield of alkaline-soluble and methanol soluble products of both cupric oxidation and modified cupric oxidation (on a moisture-free and ash-free basis) was carried out by both ion chromatography and gel permeation chromatography. Fractionation of lignite for natural-uninoculated-biological growth resulted in no growth for both benzene-methanol fraction and alkaline filtrate fraction, whereas that of alkaline geletinous fraction resulted in positive growth of unidentified white-rot fungi. Acclimation of Polyporus versicolor to lignite was attempted.more » 10 refs.« less
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Bunnell, J.E.; Tatu, C.A.; Bushon, R.N.; Stoeckel, D.M.; Brady, A.M.G.; Beck, M.; Lerch, H.E.; McGee, B.; Hanson, B.C.; Shi, R.; Orem, W.H.
2006-01-01
In May and September, 2002, 14 private residential drinking water wells, one dewatering well at a lignite mine, eight surface water sites, and lignite from an active coal mine were sampled in five Parishes of northwestern Louisiana, USA. Using a geographic information system (GIS), wells were selected that were likely to draw water that had been in contact with lignite; control wells were located in areas devoid of lignite deposits. Well water samples were analyzed for pH, conductivity, organic compounds, and nutrient and anion concentrations. All samples were further tested for presence of fungi (cultures maintained for up to 28 days and colonies counted and identified microscopically) and for metal and trace element concentration by inductively-coupled plasma mass spectrometry and atomic emission spectrometry. Surface water samples were tested for dissolved oxygen and presence of pathogenic leptospiral bacteria. The Spearman correlation method was used to assess the association between the endpoints for these field/laboratory analyses and incidence of cancer of the renal pelvis (RPC) based on data obtained from the Louisiana Tumor Registry for the five Parishes included in the study. Significant associations were revealed between the cancer rate and the presence in drinking water of organic compounds, the fungi Zygomycetes, the nutrients PO4 and NH3, and 13 chemical elements. Presence of human pathogenic leptospires was detected in four out of eight (50%) of the surface water sites sampled. The present study of a stable rural population examined possible linkages between aquifers containing chemically reactive lignite deposits, hydrologic conditions favorable to the leaching and transport of toxic organic compounds from the lignite into the groundwater, possible microbial contamination, and RPC risk. ?? Springer Science+Business Media B.V. 2006.
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NASA Astrophysics Data System (ADS)
Kan, R.; Kaosol, T.; Tekasakul, P.; Tekasakul, S.
2017-09-01
Determination of particle-bound Polycyclic Aromatic Hydrocarbons (PAHs) emitted from co-pelletization combustion of lignite and rubber wood sawdust in a horizontal tube furnace is investigated using High Performance Liquid Chromatography with coupled Diode Array and Fluorescence Detection (HPLC-DAD/FLD). The particle-bound PAHs based on the mass concentration and the toxicity degree are discussed in the different size ranges of the particulate matters from 0.07-11 μm. In the present study, the particle-bound PAHs are likely abundant in the fine particles. More than 70% of toxicity degree of PAHs falls into PM1.1 while more than 80% of mass concentration of PAHs falls into PM2.5. The addition of lignite amount in the co-pelletization results in the increasing concentration of either 4-6 aromatic ring PAHs or high molecular weight PAHs. The high contribution of 4-6 aromatic ring PAHs or high molecular weight PAHs in the fine particles should be paid much more attention because of high probability of human carcinogenic. Furthermore, the rubber wood sawdust pellets emit high mass concentration of PAHs whereas the lignite pellets emit high toxicity degree of PAHs. By co-pelletized rubber wood sawdust with lignite (50% lignite pellets) has significant effect to reduce the toxicity degree of PAHs by 70%.
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Zeller, Howard D.
1953-01-01
Core drilling in the Car H area, Slim Buttes, Harding County, South Dakota, under a contract with the B. H. Mott Drilling Co., Huntington, West Virginia, was resumed June 12, 1952 after a 6-month recess during the winter and was completed July 18, 1952. The drilling was undertaken to obtain information on the distribution and extent of the uranium-bearing lignite beds along the southeast edge of the Bar H area. Eight holes totalling 885 feet were drilled and 52 feet of lignite core submitted for study and analysis. The report includes detailed lithographic descriptions of the lignite cores, Bureau of Mines coal analyses, and the results of 100 chemical analyses for uranium. The drilling showed that the thicker, more persistent lignite beds exposed in the northern part of the Bar H area were removed by erosion prior to the deposition of the overlaying White River formation in the south-eastern part of the area. The beds penetrated by drilling were not of sufficient thickness or uranium content to add to the previously known reserves.
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Cofiring lignite with hazelnut shell and cotton residue in a pilot-scale fluidized bed combustor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zuhal Gogebakan; Nevin Selcuk
In this study, cofiring of high ash and sulfur content lignite with hazelnut shell and cotton residue was investigated in 0.3 MWt METU Atmospheric Bubbling Fluidized Bed Combustion (ABFBC) Test Rig in terms of combustion and emission performance of different fuel blends. The results reveal that cofiring of hazelnut shell and cotton residue with lignite increases the combustion efficiency and freeboard temperatures compared to those of lignite firing with limestone addition only. CO{sub 2} emission is not found sensitive to increase in hazelnut shell and cotton residue share in fuel blend. Cofiring lowers SO{sub 2} emissions considerably. Cofiring of hazelnutmore » shell reduces NO and N{sub 2}O emissions; on the contrary, cofiring cotton residue results in higher NO and N{sub 2}O emissions. Higher share of biomass in the fuel blend results in coarser cyclone ash particles. Hazelnut shell and cotton residue can be cofired with high ash and sulfur-containing lignite without operational problems. 32 refs., 12 figs., 11 tabs.« less
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Gao, Yuan; Tahmasebi, Arash; Dou, Jinxiao; Yu, Jianglong
2016-05-01
Oxy-fuel combustion of solid fuels is seen as one of the key technologies for carbon capture to reduce greenhouse gas emissions. The combustion characteristics of lignite coal, Chlorella vulgaris microalgae, and their blends under O2/N2 and O2/CO2 conditions were studied using a Thermogravimetric Analyzer-Mass Spectroscopy (TG-MS). During co-combustion of blends, three distinct peaks were observed and were attributed to C. vulgaris volatiles combustion, combustion of lignite, and combustion of microalgae char. Activation energy during combustion was calculated using iso-conventional method. Increasing the microalgae content in the blend resulted in an increase in activation energy for the blends combustion. The emissions of S- and N-species during blend fuel combustion were also investigated. The addition of microalgae to lignite during air combustion resulted in lower CO2, CO, and NO2 yields but enhanced NO, COS, and SO2 formation. During oxy-fuel co-combustion, the addition of microalgae to lignite enhanced the formation of gaseous species. Copyright © 2016 Elsevier Ltd. All rights reserved.
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NASA Astrophysics Data System (ADS)
Agrawal, Shailesh; Verma, Poonam; Rao, M. R.; Garg, Rahul; Kapur, Vivesh V.; Bajpai, Sunil
2017-09-01
This study presents new results of combined palynological and stable carbon isotope (δ13C) investigations carried out in the well known lignite sequence at Panandhro, District Kutch, in the Gujarat state of western India. Dinoflagellate cysts and associated spore-pollen assemblage assign an early Eocene (Ypresian) age to the lignitic succession at Panandhro. Furthermore, a pronounced negative Carbon Isotope Excursion (CIE) of about 2.7‰, correlated to the Second Eocene Thermal Maximum (53.7 Ma), a globally recognized hyperthermal event, was discovered in the middle part of the succession, consistent with the palynological constraints. This is the first record of an Eocene hyperthermal event (ETM2) from the Kutch Basin. Our data has regional implications for the age of the lignitic sequences across western India as it demonstrates that there is no significant age difference between the lignite deposits of the Kutch and Cambay basins. Our results also support a Lutetian age for the previously described vertebrate fossils, including whales, from the Panandhro mine section.
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Humic Acid Isolations from Lignite by Ion Exchange Method
NASA Astrophysics Data System (ADS)
Kurniati, E.; Muljani, S.; Virgani, D. G.; Neno, B. P.
2018-01-01
The humic liquid is produced from lignite extraction using alkali solution. Conventional humic acid is obtained by acidifying a humic solution using HCl. The purpose of this research is the formation of solid humic acid from lignite by ion exchange method using cation resin. The results showed that the addition of cation resin was able to reduce the pH from 14 to pH 2 as well as the addition of acid (HCl), indicating the exchange of Na + ions with H + ions. The reduction of pH in the humic solution is influenced by the concentration of sodium ions in the humic solution, the weight of the cation resin, and the ion exchange time. The IR spectra results are in good agreement for humic acid from lignite characterization.
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Study on the coal mixing ratio optimization for a power plant
NASA Astrophysics Data System (ADS)
Jin, Y. A.; Cheng, J. W.; Bai, Q.; Li, W. B.
2017-12-01
For coal-fired power plants, the application of blended coal combustion has been a great issue due to the shortage and rising prices of high-rank coal. This paper describes the optimization of blending methods between Xing'an lignite coal, Shaltala lignite coal, Ura lignite coal, and Inner Mongolia bituminous coal. The multi-objective decision-making method based on fuzzy mathematics was used to determine the optimal blending ratio to improve the power plant coal-fired economy.
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2007-08-01
The backfill material shall be free of bentonite, trash, frozen or organic material including lignites, humus , sod, grass, roots or other...organic material including lignites, humus , sod, grass, roots or other vegetation. The backfill material shall not be of a size greater than 3 inches, may...lignites, humus , sod, grass, roots or other vegetation. The backfill material shall not be of a size greater than 3 inches, may not contain more than 12
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Preliminary geologic investigation of the West Glendive lignite deposits, Dawson County, Montana
Banet, Arthur C.
1979-01-01
Four major lignite beds, all in the Fort Union Formation (Paleocene), occur in the West Glendive area, Dawson County, Montana. The Newton Ranch and Poverty Flats beds are in the Lebo Member and the Peuse and Kolberg Ranch beds are in the Tongue River Member. Correlation of the lignite beds across the area shows that the Peuse bed is the thickest and most extensive. Field mapping and drill-hole data indicate that folding and faulting are more common than previously reported.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Cronauer, D.C.; Swanson, A.J.; Sajkowski, D.J.
Research under way in this project centers upon developing and evaluating catalysts and process improvements for coal liquefaction in the two-stage, close-coupled catalytic process. As discussed in the previous quarterly report, the feedstock liquefaction studies for the three feedstocks (Black Thunder subbituminous coal, Martin Lake lignite, and Illinois No. 6 coal) were completed. Both Black Thunder coal and Martin Lake lignite gave lighter products than Illinois No. 6 coal at similar process conditions. Severe catalyst deactivation in the first stage was also observed with the Martin Lake lignite run. The first stage catalyst testing program was started (Task 3.2.1). Aftermore » a successful reference run with Illinois No. 6 coal, a high-temperature run with AMOCAT{trademark} 1C was completed, where the results showed that the first stage temperature should be no higher than 820{degrees}F. In addition, several runs were made both with Illinois No. 6 and Black Thunder coals using oil-soluble catalysts, Molyvan L, and molybdenum octoate in one or both stages. Overall, the results look very promising and show that dispersed molybdenum catalysts are good alternatives for Stage 1 or both 1 and 2, especially for Illinois No. 6 coal. In the case of Black Thunder coal, the conversion and yields were good, although the product quality was poorer, however, the use of slurry catalysts is still recommended.« less
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NASA Astrophysics Data System (ADS)
Batzias, Dimitris F.; Pollalis, Yannis A.
2012-12-01
In this paper, optimal environmental policy for reclamation of land unearthed in lignite mines is defined as a strategic target. The tactics concerning the achievement of this target, includes estimation of optimal time lag between each lignite site (which is a segment of the whole lignite field) complete exploitation and its reclamation. Subsidizing of reclamation has been determined as a function of this time lag and relevant implementation is presented for parameter values valid for the Greek economy. We proved that the methodology we have developed gives reasonable quantitative results within the norms imposed by legislation. Moreover, the interconnection between strategy and tactics becomes evident, since the former causes the latter by deduction and the latter revises the former by induction in the time course of land reclamation.
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Orem, W.H.; Feder, G.L.; Finkelman, R.B.
1999-01-01
Balkan endemic nephropathy (BEN) is a fatal kidney disease that is known to occur only in clusters of villages in alluvial valleys of tributaries of the Danube River in Bulgaria, Romania, Yugoslavia, Bosnia, and Croatia. The confinement of this disease to a specific geographic area has led to speculation that an environmental factor may be involved in the etiology of BEN. Numerous environmental factors have been suggested as causative agents for producing BEN, including toxic metals in drinking water, metal deficiency in soils of BEN areas, and environmental mycotoxins to name a few. These hypotheses have either been disproved or have failed to conclusively demonstrate a connection to the etiology of BEN, or the clustering of BEN villages. In previous work, we observed a distinct geographic relationship between the distribution of Pliocene lignites in the Balkans and BEN villages. We hypothesized that the long-term consumption of well water containing toxic organic compounds derived from the leaching of nearby Pliocene lignites by groundwater was a primary factor in the etiology of BEN. In our current work, chemical analysis using 13C nuclear magnetic resonance (13CNMR) spectroscopy indicated a high degree of organic functionality in Pliocene lignite from the Balkans, and suggested that groundwater can readily leach organic matter from these coal beds. Semi-quantitative gas chromatography/mass spectroscopy analysis of solvent extracts of groundwater from shallow wells in BEN villages indicated the presence of potentially toxic aromatic compounds, such as napthalene, fluorene, phenanthrene, and pyrene at concentrations in the ppb range. Laboratory leaching of Balkan Pliocene lignites with distilled water yielded soluble organic matter (> 500 MW) containing large amounts of aromatic structures similar to the simple/discrete aromatic compounds detected in well water from BEN villages. These preliminary results are permissive of our hypothesis and suggest that further work on the possible relationship between the etiology of BEN and toxic aromatic substances leached from Pliocene lignites in well water is warranted.A distinct geographic relationship between the distribution of Pliocene lignites in the Balkans and villages where Balkan endemic nephropathy (BEN) occurs has been observed, indicating a possible link between BEN and the long-term consumption of well water containing toxic organic compounds derived from the leaching of nearby Pliocene lignites. Preliminary investigations by NMR spectroscopy, gas chromatography/mass spectroscopy and leaching experiments show a high degree of organic functionality in the Pliocene lignites, high-leachability by groundwater of organic matter from these beds, and the presence of toxic aromatic compounds.
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NASA Astrophysics Data System (ADS)
Fotakis, M.; Tsikritzis, L.; Tzimkas, N.; Kolovos, N.; Tsikritzi, R.
2008-08-01
West Macedonia Lignite Center (WMLC), located in Northwest Greece, releases into the atmosphere about 21,400 tons/year of fly ash through the stacks of four coal fired plants. The lignite ash contains naturally occurring radionuclides, which are deposited on the WMLC basin. This work investigates the natural radioactivity of twenty six ash samples, laboratory produced from combustion of lignite, which was sampled perpendicularly to the benches of the Kardia mine. The concentrations of radionuclides 40K, 235U, 238U, 226Ra, 228Ra and 232Th, were measured spectroscopically and found round one order of magnitude as high as those of lignite. Subsequently the Radionuclide Partitioning Coefficients of radionuclides were calculated and it was found that they are higher for 232Th, 228Ra and 40K, because the latter have closer affinity with the inorganic matrix of lignite. During combustion up to one third of the naturally occurring radioisotopes escape from the solid phase into the flue gases. With comparison to relative global data, the investigated ash has been found to have relatively high radioactivity, but the emissions of the WMLC radionuclides contribute only 0.03% to the mean annual absorbed dose.
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Environmental geology of the Wilcox Group Lignite Belt, east Texas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Henry, C.D.; Basciano, J.M.
This report provides a data base for decisions about lignite mining and reclamation in the Wilcox Group of East Texas. A set of environmental geologic maps, which accompanies this report, depicts the character of the land that will be affected by mining. The environmental geologic maps of the East Texas lignite belt provide an accurate inventory of land resources. The maps identify areas where mining is most likely to occur, areas of critical natural resources that could be affected by mining, such as aquifer recharge areas, and areas of natural hazards, such as floodplains. Principal areas of both active andmore » planned surface mining are also located. The seven environmental geologic maps cover the outcrop area of the Wilcox Group, the major lignite host, and adjacent geologic units from Bastrop County to Texarkana. This report begins with a discussion of various physical aspects of the lignite belt, including geology, hydrology, soils, climate, and land use, to aid in understanding the maps. The criteria and methodology used to delineate the environmental geologic units are discussed. Varied applications of the environmental geologic maps are considered. 23 references, 9 figures, 3 tables.« less
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Leaching behavior of rare earth elements in Fort Union lignite coals of North America
DOE Office of Scientific and Technical Information (OSTI.GOV)
Laudal, Daniel A.; Benson, Steven A.; Addleman, Raymond Shane
Rare earth elements are crucial materials in an incredible array of consumer goods, energy system components and military defense applications. However, the global production and entire value chain for rare earth elements is dominated by China, with the U.S. currently 100% import reliant for these critical materials. Traditional mineral ores including those previously mined in the U.S., however, have several challenges. Chief among these is that the content of the most critical and valuable of the rare earths are deficient, making mining uneconomical. Further, the supply of these most critical rare earths is nearly 100% produced in China from amore » single resource that is only projected to last another 10 to 20 years. The U.S. currently considers the rare earths market an issue of national security. It is imperative that alternative domestic sources of rare earths be identified and methods developed to produce them. Recently, coal and coal byproducts have been identified as one of these promising alternative resources. This paper details the results of a study on characterization of North Dakota lignite and lignite-related feedstocks as an assessment of their feasibility for rare earth element recovery. The abundance, distribution and modes of occurrence of the rare earth elements in the samples collected were determined in this initial study to inform the selection of appropriate extraction and concentration methods to recover the rare earth elements. Materials investigated include the lignite coals, clay-rich sediments associated with the coal seams, and materials associated with a lignite beneficiation system and power plant. The results show that high rare earth element levels exist both in lignite coals and associated sediments. The form of the rare earth elements in the clay materials is primarily as ultra-fine mineral grains. In the lignite coals, approximately 80-95% of the rare earths content is organically associated, primarily as coordination complexes.« less
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Paleocene-eocene lignite beds of southwest Alabama: Parasequence beds in highstand systems tracts
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mancini, E.A.; Tew, B.H.; Carroll, R.E.
1993-09-01
In southwest Alabama, lignite beds are present in at least four stratigraphic intervals that span approximately 8 m.y. of geologic time. Lignite is found in the Paleocene Oak Hill Member and Coal Bluff Member of the Naheola Formation of the Midway Group and the Paleocene Tuscahoma Sand and the Eocene Hatchetigbee Formation of the Wilcox Group. Lignite beds range in thickness from 0.5 to 11 ft and consist of 32-53% moisture, 13-39% volatile matter, 4-36% fixed carbon, and 5-51% ash. These Paleocene and Eocene lignite beds occur as parasequence deposits in highstand systems tracts of four distinct third-order depositional sequences.more » The lignite beds are interpreted as strata within highstand systems tract parasequences that occur in mud-dominated regressive intervals. Lignite beds were deposited in coastal marsh and low-lying swamp environments as part of deltaic systems that prograded into southwestern Alabama from the west. As sediment was progressively delivered into the basin from these deltas, the effects of relative sea level rise during an individual cycle were overwhelmed, producing a net loss of accommodation and concomitant overall basinward progradation of the shoreline (regression). Small-scale fluctuations in water depth resulting from the interaction of eustasy, sediment yield, and subsidence led to cyclical flooding of the low-lying coastal marshes and swamps followed by periods of progradational and regression. Highstand systems tract deposition within a particular depositional sequence culminated with a relative sea level fall that resulted in a lowering of base level and an abrupt basinward shift in coastal onlap. Following sea level fall and the subsequent accumulation of the lowstand deposits, significant relative sea level rise resulted in the marine inundation of the area previously occupied by coastal marshes and swamps and deposition of the transgressive systems tract of the overlying sequence.« less
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Natural desulfurization in coal-fired units using Greek lignite.
Konidaris, Dimitrios N
2010-10-01
This paper analyzes the natural desulfurization process taking place in coal-fired units using Greek lignite. The dry scrubbing capability of Greek lignite appears to be extremely high under special conditions, which can make it possible for the units to operate within the legislative limits of sulfur dioxide (SO2) emissions. According to this study on several lignite-fired power stations in northern Greece, it was found that sulfur oxide emissions depend on coal rank, sulfur content, and calorific value. On the other hand, SO2 emission is inversely proportional to the parameter gammaCO2(max), which is equal to the maximum carbon dioxide (CO2) content by volume of dry flue gas under stoichiometric combustion. The desulfurization efficiency is positively correlated to the molar ratio of decomposed calcium carbonate to sulfur and negatively correlated to the free calcium oxide content of fly ash.
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Warwick, Peter D.; Crowley, Sharon S.; Ruppert, Leslie F.; Pontolillo, James
1997-01-01
This study examined the petrographic and geochemical characteristics of two lignite beds (3500 and 4500 beds, Manning Formation, Jackson Group, Eocene) that are mined at the Gibbons Creek mine in east-central Texas. The purpose of the study was to identify the relations among sample ash yield, coal petrography, and trace-element concentrations in lignite and adjoining rock layers of the Gibbons Creek mine. Particular interest was given to the distribution of 12 environmentally sensitive trace elements (As, Be, Cd, Cr, Co, Hg, Mn, Ni, Pb, Sb, Se, and U) that have been identified as potentially hazardous air pollutants (HAPs) in the United States Clean Air Act Amendments of 1990. Eleven lignite, floor, and rock parting samples were collected from incremental channel samples of the 3500 and 4500 beds that were exposed in a highwall of pit A3 at the Gibbons Creek mine. Short proximate and ultimate and forms of sulfur analyses were performed on all lignite samples, and lignite and rock samples were analyzed for 60 major, minor and trace elements. Representative splits of all lignite samples were ground and cast into pellets, and polished for petrographic analyses in blue-light fluorescence and reflected white light to determine liptinite, inertinite, and huminite maceral group percentages. The following observations summarize our results and conclusions about the geochemistry, petrography, and sedimentology of the 3500 and 4500 beds of the Gibbons Creek lignite deposit: (1) Weighted average dry (db) ash yield for the two beds is 29.7%, average total sulfur content is 2.6%, and average calorific value is 7832 Btu (18.22 MJ/kg). Ash yields are greatest in the lower bench (59.33% db) of the 3500 bed and in the upper bench of the 4500 bed (74.61% db). (2) For lignite samples (on a whole-coal basis), the distributions of two of the HAPs (Pb and Sb) are positively related to ash yield, probably indicating an inorganic affinity for these elements. By using cluster analysis we found that Be and Cd were poorly associated with ash yield, indicating a possible organic affinity, and that Ni, Se, Hg, U, and Pb cluster with most of the rare-earth elements. (3) The dominance of the crypto-eugelinite maceral subgroup over the crypto-humotelinite subgroup suggests that all Gibbons Creek lignites were subjected to peat-forming conditions (either biogenic or chemical) conducive to the degradation of wood cellular material into matrix gels, or that original plant material was not very woody and was prone to formation of matrix gels. The latter idea is supported by pollen studies of Gibbons Creek lignite beds; results indicate that the peat was derived in part from marsh plants low in wood tissue. (4) The occurrence of siliceous sponge spicules in the lower benches of the 3500 bed suggests the original peat in this part of the bed was deposited in standing, fresh water. (5) The petrographic data indicate that the upper sample interval of the 3500 bed contains more inertinite (3%) than the other samples studied. Increases in inertinite content in the upper part of the 3500 bed may have been associated with alteration of the peat by acids derived from the volcanic ash or could have been caused by fire, oxidation and drying, or biologic alteration of the peat in the paleo-mire.
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Cao, Xiaoyan; Drosos, Marios; Leenheer, Jerry A; Mao, Jingdong
2016-02-16
A lignite humic acid (HA) was separated from inorganic and non-HA impurities (i.e., aluminosilicates, metals) and fractionated by a combination of dialysis and XAD-8 resin. Fractionation revealed a more homogeneous structure of lignite HA. New and more specific structural information on the main lignite HA fraction is obtained by solid-state nuclear magnetic resonance (NMR) spectroscopy. Quantitative (13)C multiple cross-polarization (multiCP) NMR indicated oxidized phenyl propane structures derived from lignin. MultiCP experiments, conducted on potassium HA salts titrated to pH 10 and pH 12, revealed shifts consistent with carboxylate and phenolate formation, but structural changes associated with enolate formation from aromatic beta keto acids were not detected. Two-dimensional (1)H-(13)C heteronuclear correlation (2D HETCOR) NMR indicated aryl-aliphatic ketones, aliphatic and aromatic carboxyl groups, phenol, and methoxy phenyl ethers. Acidic protons from carboxyl groups in both the lignite HA fraction and a synthetic HA-like polycondensate were found to be hydrogen-bonded with electron-rich aromatic rings. Our results coupled with published infrared spectra provide evidence for the preferential hydrogen bonding of acidic hydrogens with electron-rich aromatic rings rather than adjacent carbonyl groups. These hydrogen-bonding interactions likely result from stereochemical arrangements in primary structures and folding.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Echols, J.B.; Goddard, D.A.; Bouma, A.
The Bee Brake field area, located in township 4N/6E and 4N/7E in Concordia Parish, has been one of the more prolific oil-producing areas in east-central Louisiana. Production decline in various fields, however, has sparked interest in the economic feasibility of locating and producing the remaining bypassed oil in the lower Wilcox. For this purpose, the Angelina BBF No. 1 well was drilled, and a 500-ft conventional core and a complete suite of state-of-the-are wireline logs were recovered. Production tests were run on the Minter interval of interest. The 16-ft Minter interval (6742-6758 ft depth), bounded at its top and basemore » by lignite seams, consists of an upper 4-ft oil sand (Bee Brake) and a lower 3-ft oil sand (Angelina). The oil sands are separated by approximately 5 ft of thinly laminated silty shale and 4 ft of very fine-grained silty sandstone. Detailed sedimentologic and petrographic descriptions of the Minter interval provide accurate facies determinations of this lower delta-plain sequence. Petrophysical evaluation, combining core plug and modern electric-log data show differences between reservoir quality of the Bee Brake and Angelina sands. This data will also be useful for correlating and interpolating old electric logs. Organic geochemistry of the oil, lignites, and shales provides insight as to the source of the Minter oils and the sourcing potential of the lignites.« less
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Effects of hauling timber, lignite coal, and coke fuel on Louisiana highways and bridges.
DOT National Transportation Integrated Search
2005-03-01
This study included the development of a methodology to assess the economic impact of overweight permitted vehicles hauling timber, lignite coal, and coke fuel on Louisiana highways and bridges. Researchers identified the highway routes and bridges b...
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Hydrology of area 46, Northern Great Plains and Rocky Mountain coal provinces, North Dakota
Croft, M.G.; Crosby, Orlo A.
1987-01-01
This report is one of a series that describes the hydrology of coal provinces nationwide. The Northern Great Plains and Rocky Mountain Coal Provinces are divided into 20 separate reporting areas which are numbered 43 to 62. This report provides general hydrologic information for Area 46 using a brief text with accompanying maps, charts, or graphs. This information may be used to describe the hydrology of the general area of any existing or proposed mine. Some of the more obvious hydrologic problems of coal development that will need to be addressed before development are disruption of aquifers and potential contamination of streams, aquifers, and the atmosphere.Area 46 is in northwestern North Dakota and is composed of parts or all of 14 hydrologic units based on surface-water drainage basins. The area is drained by the Missouri and Souris Rivers.Lignite-bearing rocks of late Paleocene age underlie nearly all of Area 46. The thickest and most continuous lignite beds occur in the Sentinel Butte and Tongue River Members of the Fort Union Formation. Alluvial deposits and a veneer of glacial drift of late Pleistocene age overlie the lignite-bearing rocks. The climate of the area is semiarid. Mean annual precipitation ranges from 13.9 to 17.8 inches. Mean annual temperatures range from 37.7°F at Bowbells to 40.9°F at Williston. Mean monthly temperatures at Williston range from 8.3°F to 70°F. The growing season is about 125 days.A fairly comprehensive data base for streamflow and water quality in streams is available for Area 46. Many of the small-stream monitoring sites have been operated during the last few years to provide a data base before coal development. With the exception of the Missouri River, which is controlled by several dams, both the quantity and quality of water varies greatly in all streams. A ground-water observation network for water levels and water quality has been established through county ground-water resource investigations and other ground-water studies and provides an adequate data base. Three activities within the U.S. Geological Survey identify and provide access to hydrologic data. These are the National Water-Data Exchange (NAWDEX), the National Water-Data Storage and Retrieval System (WATSTORE), and the Office of Water-Data Coordination (OWDC).
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Adeli, Ardeshir; Read, John J; Brooks, John P; Miles, Dana; Feng, Gary; Jenkins, Johnie N
2017-03-01
The inability to incorporate broiler litter (BL) into permanent hayfields and pastures leads to nutrient accumulation near the soil surface and increases the potential transport of nutrients in runoff. This study was conducted on Marietta silt loam soil to determine the effect of flue gas desulfurization (FGD) gypsum and lignite on P, N, C, and microbial concentrations in runoff. Treatments were (i) control (unfertilized) and (ii) BL at 13.4 Mg ha alone or (iii) treated with either FGD gypsum or lignite applied at 20% (w/w) (2.68 Mg ha). Rainfall simulators were used to produce a 5.6 cm h storm event sufficient in duration to cause 15 min of continuous runoff. Repeated rains were applied at 3-d intervals to determine how long FGD gypsum and lignite are effective in reducing loss of litter-derived N, P, and C from soil. Application of BL increased N, P, and C concentrations in runoff as compared to the control. Addition of FGD gypsum reduced ( < 0.05) water-soluble P and dissolved organic C concentrations in runoff by 39 and 16%, respectively, as compared to BL alone. Lignite reduced runoff total N and NH-N concentrations by 38 and 70%, respectively, as compared to BL alone. Addition of FGD gypsum or lignite failed to significantly reduce microbial loads in runoff, although both treatments reduced microbial concentration by >20%. Thus, BL treated with FGD and lignite can be considered as cost-effective management practices in the mitigation of P, N, and C and possibly microbial concentration in runoff. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Goyen, S.; Baily, E.; Mawer, J.
1980-10-01
The objective of the work reported herein was to develop a preliminary conceptual design, capital requirements, and product cost for a lignite-to-methanol plant incorporating Winkler Gasification Technology and ICI Methanol synthesis. The lignite-to-methanol complex described herein is designed to produce 15,000 TPD of fuel grade methanol. The complex is designed to be self-sufficient with respect to all utility services, offsites, and other support facilities, including power generation. Following is a summary of the results of the study: (1) Tons per day (TPD) of Lignite Feedstock and Fuel (as received) was 47,770; (2) TPD of Fuel Grade Methanol Product was 15,000;more » (3) Thermal efficiency, % (HHV) was 47.4; (4) Plant investment expressed in terms of first quarter of 1980 was ($ Million) 1545; and (5) Applying the economic premises used by EPRI for fuel conversion plant utility type financing, the calculated levelized and first year product costs are included.« less
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Combustion behavior of different kinds of torrefied biomass and their blends with lignite.
Toptas, Asli; Yildirim, Yeliz; Duman, Gozde; Yanik, Jale
2015-02-01
In this study, the combustion behavior of different kinds of torrefied biomass (lignocellulosic and animal wastes) and their blends with lignite was investigated via non-isothermal thermogravimetric method under air atmosphere. For comparison, combustion characteristics of raw biomasses were also determined. Torrefaction process improved the reactivity of char combustion step of biomasses. Characteristic combustion parameters for blends showed non-additivity behavior. It was found that the mixture of torrefied biomasses and lignite at a ratio of 1:1 had a lower ignition and burnout temperature than the coal-only sample. Although no interactions were observed between the lignite and torrefied biomass at initial step of combustion, a certain degree of interaction between the components occurred at char combustion step. Kinetic parameters of combustion were calculated by using the Coats Redfern model. Overall, this study showed that poultry litters can be used as a substitute fuel in coal/biomass co-firing systems by blending with lignocellulosic biomass. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Li, Hao; Xia, Shuqian; Ma, Peisheng
2016-10-01
Co-combustion of lignite with distillation residue derived from rice straw pyrolysis oil was investigated by non-isothermal thermogravimetric analysis (TGA). The addition of distillation residue improved the reactivity and combustion efficiency of lignite, such as increasing the weight loss rate at peak temperature and decreasing the burnout temperature and the total burnout. With increasing distillation residue content in the blended fuels, the synergistic interactions between distillation residue and lignite firstly increased and then decreased during co-combustion stage. Results of XRF, FTIR, (13)C NMR and SEM analysis indicated that chemical structure, mineral components and morphology of samples have great influence on the synergistic interactions. The combustion mechanisms and kinetic parameters were calculated by the Coats Redfern model, suggesting that the lowest apparent activation energy (120.19kJ/mol) for the blended fuels was obtained by blending 60wt.% distillation residue during main co-combustion stage. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Petrographic Composition of Lignite from the Lake Somerville Spillway (East-central Texas)
NASA Astrophysics Data System (ADS)
Pawelec, Sandra; Bielowicz, Barbara
2017-12-01
In the presented paper, the macroscopic and microscopic composition of lignite from Lake Somerville Spillway has been examined. The study area is the upper part of the Manning Formation, located north-west of Somerville in the central-eastern part of Texas. There are three exposures: NE, SW and MC (Main Central) with visible parts of late-Eocene lignite seams belonging to the Jackson Group. The Manning section is divided into four marine dominated parasequences (P1 through P4). Lignite samples outlining the P1 parasequence from the MC and NE outcrops and the argillate sample from the lower part of the P2 parasequence, NE outcrop. Macroscopic characterization was carried out based on lithological classifications of humic coal. On this basis, it has been shown that the main lithotype occurring in the deposit is detritic (matrix) coal with a high share of mineral matter. The maceral composition of coal was determined according to the ICCP guidelines. The macerals from liptinite group were determined under fluorescent light. The maceral group content analysis was performed with use of 500-600 equally spaced points on the surface of the polished sections. It has been found that the examined coal is dominated by macerals from the huminite group, with a share ranging from 20.8 to 65.3% volume, including atrinite (9.8-22.8% volume, 17.5% volume on average). In the examined coal, macerals from the inertinite group (10.1 to 44.8%), especially semifusinite (max. 13.9%), fusinite (max. 9.3%) and funginite (max. 6.3 %) are of particularly large share. In the liptinite group, particular attention was paid to the content of alginite (max. 4.5%) and bituminite (max. 1.3 %), which indicate the paralic sedimentation environment of the examined coal. Additionally, the variability of macerals and maceral groups within the exposures and levels of the P1 parasequence was examined. The last step was to compare lignite from Lake Somerville Spillway with other lignites belonging to the Jackson Group, namely Gibbons Creek and San Miguel lignite mines.
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NASA Astrophysics Data System (ADS)
Murugappan, A.; Manoharan, A.; Senthilkumar, G.; Krishnamurthy, J.
2017-07-01
Irrigated farming depends on an ample supply of water compatible quality. Presently, a lot of irrigation projects have to depend on inferior quality and not so enviable sources of water supply. In order to prevent troubles during usage of such water supplies of poor quality, there must be meticulous preparation to ensure that the water available with such quality characteristics is put to best use. The effect of water quality upon soil and crops must be better understood in choosing fitting options to manage with impending water quality associated troubles that might decrease soil and crop productivity under existing circumstances of water use. Two tanks (small sized reservoirs) namely, Walajah Tank and Perumal Tank in Cuddalore District, used for irrigation, receive mine drainage water pumped out continuously from the open cast lignite mines of the NLC India Limited, Neyveli, Tamilnadu State. This water has been used by the farmers in the irrigated commands of both Walajah Tank and Perumal Tank for more than three decades. Recently, the beneficiaries had raised fears on the quality of mine drainage waters they had been using for raising crops in the commands of both the tanks. They opined that the coal dust laden mine water used for irrigation had affected the crop yields. This incited us to take up a study to (i) assess the status of quality of surface waters released from the two tanks for irrigation in the respective command areas and (ii) assess the likely impacts of quality of water on soil and on growth and productivity of crops cultivated in the command areas. Further to the technical evaluation of the impacts, a structured questionnaire survey was also conducted among the farmers and the common public in the study area. The findings of the survey confirmed with the outcome of the technical assessment in that the mine drainage had a poor impact in the cultivable command area of Walajah tank system while such impacts were less significant in most parts of the command area of Perumal tank system.
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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.
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NASA Astrophysics Data System (ADS)
Gontaszewska-Piekarz, Agnieszka; Mrówczyńska, Maria
2018-04-01
The paper presents the possibilities of using data obtained by airborne laser scanning for identifying areas where lignite used to be mined. The technology of airborne laser scanning presented in the paper as and its results have a vast potential in terms of identifying local terrain deformations. The paper also presents the history of lignite mining in the region of Ośno Lubuskie (the north-west of Ziemia Lubuska - western Poland). It describes underground mining in complicated geological conditions (glaciotectonic deformations). The paper is supplemented with historical maps showing the locations of the mines
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Kucera, Dan; Benesova, Pavla; Ladicky, Peter; Pekar, Miloslav; Sedlacek, Petr; Obruca, Stanislav
2017-01-01
Polyhydroxyalkanoates (PHAs) are bacterial polyesters which are considered biodegradable alternatives to petrochemical plastics. PHAs have a wide range of potential applications, however, the production cost of this bioplastic is several times higher. A major percentage of the final cost is represented by the price of the carbon source used in the fermentation. Burkholderia cepacia and Burkholderia sacchari are generally considered promising candidates for PHA production from lignocellulosic hydrolyzates. The wood waste biomass has been subjected to hydrolysis. The resulting hydrolyzate contained a sufficient amount of fermentable sugars. Growth experiments indicated a strong inhibition by the wood hydrolyzate. Over-liming and activated carbon as an adsorbent of inhibitors were employed for detoxification. All methods of detoxification had a positive influence on the growth of biomass and PHB production. Furthermore, lignite was identified as a promising alternative sorbent which can be used for detoxification of lignocellulose hydrolyzates. Detoxification using lignite instead of activated carbon had lower inhibitor removal efficiency, but greater positive impact on growth of the bacterial culture and overall PHA productivity. Moreover, lignite is a significantly less expensive adsorbent in comparison with activated charcoal and; moreover, used lignite can be simply utilized as a fuel to, at least partially, cover heat and energetic demands of fermentation, which should improve the economic feasibility of the process. PMID:28952532
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NASA Astrophysics Data System (ADS)
Jeschke, Christina; Knöller, Kay; Koschorreck, Matthias; Ussath, Maria; Hoth, Nils
2014-05-01
In Germany, a major share of the energy production is based on the burning of lignite from open cast pit mines. The remediation and re-cultivation of the former mining areas in the Lusatian and Central German lignite mining district is an enormous technical and economical challenge. After mine closures, the surrounding landscapes are threatened by acid mine drainage (AMD), i.e. the acidification and mineralization of rising groundwater with metals and inorganic contaminants. The high content of sulfur (sulfuric acid, sulfate), nitrogen (ammonium) and iron compounds (iron-hydroxides) deteriorates the groundwater quality and decelerates sustainable development of tourism in (former) mining landscapes. Natural biodegradation or attenuation (NA) processes of inorganic contaminants are considered to be a technically low impact and an economically beneficial solution. The investigations of the stable isotope compositions of compounds involved in NA processes helps clarify the dynamics of natural degradation and provides specific informations on retention processes of sulfate and nitrogen-compounds in mine dump water, mine dump sediment, and residual pit lakes. In an active mine dump we investigated zones where the process of bacterial sulfate reduction, as one very important NA process, takes place and how NA can be enhanced by injecting reactive substrates. Stable isotopes signatures of sulfur and nitrogen components were examined and evaluated in concert with hydrogeochemical data. In addition, we delineated the sources of ammonium pollution in mine dump sediments and investigated nitrification by 15N-labeling techniques to calculate the limit of the conversion of harmful ammonium to nitrate in residual mining lakes. Ultimately, we provided an isotope biogeochemical assessment of natural attenuation of sulfate and ammonium at mine dump sites and mining lakes. Also, we estimated the risk potential for water in different compartments of the hydrological system. In laboratory experiments, we tested reactive materials that may speed up the process of bacterial sulfate reduction. In in-situ experiments, we quantified nitrification rates. Based on the results, we are able to suggest promising technical measures that enhance natural attenuation processes at mine dump site and in mining lakes. The natural water cycle in lignite mining landscapes is heavily impacted by human activities. Basically, nature is capable of cleaning itself to a certain extent after mining activities stopped. However, it is our responsibility to support biogeochemical processes to make them more efficient and more sustainable. Isotopic monitoring proved to be an excellent tool for assessing the relevance and performance of different re-cultivation measures for a positive long-term development of the water quality in large-scale aquatic systems affected by the impact of lignite mining.
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Low-rank coal study : national needs for resource development. Volume 2. Resource characterization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1980-11-01
Comprehensive data are presented on the quantity, quality, and distribution of low-rank coal (subbituminous and lignite) deposits in the United States. The major lignite-bearing areas are the Fort Union Region and the Gulf Lignite Region, with the predominant strippable reserves being in the states of North Dakota, Montana, and Texas. The largest subbituminous coal deposits are in the Powder River Region of Montana and Wyoming, The San Juan Basin of New Mexico, and in Northern Alaska. For each of the low-rank coal-bearing regions, descriptions are provided of the geology; strippable reserves; active and planned mines; classification of identified resources bymore » depth, seam thickness, sulfur content, and ash content; overburden characteristics; aquifers; and coal properties and characteristics. Low-rank coals are distinguished from bituminous coals by unique chemical and physical properties that affect their behavior in extraction, utilization, or conversion processes. The most characteristic properties of the organic fraction of low-rank coals are the high inherent moisture and oxygen contents, and the correspondingly low heating value. Mineral matter (ash) contents and compositions of all coals are highly variable; however, low-rank coals tend to have a higher proportion of the alkali components CaO, MgO, and Na/sub 2/O. About 90% of the reserve base of US low-rank coal has less than one percent sulfur. Water resources in the major low-rank coal-bearing regions tend to have highly seasonal availabilities. Some areas appear to have ample water resources to support major new coal projects; in other areas such as Texas, water supplies may be constraining factor on development.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kin, B.; Dincer, S.; Kuyulu, A.
The authors report the reduction and removal of sulfur compounds from Can K{sub 4}, Keles and Agacli lignite samples, obtained from mines close to Istanbul, studied using chlorine gas. Water or mixtures of methyl chloroform-water and carbon tetrachloride-water were used as solvents. Chlorine gas was bubbled through a suspension of lignite sample in solvent for about 1 to 5 hrs. It was observed that removal of sulfur increased with increasing time. Chlorinolysis and the Meyers method were used separately to compare their effects on the reduction of sulfur from Agacli and Keles lignite samples. Chlorinolysis was found to be moremore » effective than the Meyers method in the removal of organic sulfur and thus the total sulfur.« less
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ERIC Educational Resources Information Center
Robinson, Fred
Since it became known in l979 that the Arkansas Power and Light Company was going to build a large electricity generating plant near Hampton and that there would be a lignite mining operation established there to support the power plant, the Warren public schools have been preparing to meet the impact on the schools. Because it was assumed that…
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Spectral Study of Modified Humic Acids from Lignite
NASA Astrophysics Data System (ADS)
Zherebtsov, Sergey; Malyshenko, Natalya; Bryukhovetskaya, Ludmila; Ismagilov, Zinfer
2017-11-01
The IR-Fourier, ESR and solid-state 13C NMR analysis are used for investigation of unmodified and modified humic acids obtained from Tisul lignite (the Kansko-Achinsk Basin). Treatment with Hydrogen peroxide used for modification of humic acids and it changes the functionalgroup composition of the humic acids and increases the sorptional capacity
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Survival and growth of trees and shrubs on different lignite minesoils in Louisiana
James D. Haywood; Allan E. Tiarks; James P. Barnett
1993-01-01
In 1980, an experimental opencast lignite mine was developed to compare redistributed A horizon with three minesoil mixtures as growth media for woody plants. The three minesoil mixtures contained different amounts and types of overburden materials, and normal reclamation practices were followed. Loblolly pine (Pinus taeda, L.), sawtooth oak (
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Maharaj, S V M
2014-01-01
Balkan endemic nephropathy (BEN) is a chronic, tubulointerstitial renal disease often accompanied by urothelial cancer that has a lethality of nearly 100%. One of the many factors that have been proposed to play an etiological role in BEN is exposure to organic compounds from Pliocene lignite coal deposits via the drinking water in endemic areas. The objective of this study was to systematically evaluate the role of the tenets of the Pliocene lignite hypothesis in the etiology of BEN in order to provide an improved understanding of the hypothesis for colleagues and patients alike. A comprehensive compilation of the possible limitations of the hypothesis, with each limitation addressed in turn is presented. The Pliocene lignite hypothesis can best account for, is consistent with, or has the potential to explain the evidence associated with the myriad of factors related to BEN. Residents of endemic areas are exposed to complex mixtures containing hundreds of organic compounds at varying doses and their potentially more toxic (including nephrotoxic) and/or carcinogenic metabolites; however, a multifactorial etiology of BEN appears most likely.
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Pietrzykowski, Marcin; Woś, Bartłomiej; Pająk, Marek; Wanic, Tomasz; Krzaklewski, Wojciech; Chodak, Marcin
2018-06-01
Combustion wastes are characterised by extremely low N contents. Therefore, introduction of nitrogen-fixing species at the first stage of their biological reclamation is required. This paper presents an assessment of the growth parameters of alders (Alnus sp.) 10 years after their introduction to a disposal site of lignite combustion waste in Central Poland. Black (Alnus glutinosa) and grey alders (Alnus incana) were planted directly in the combustion waste. The soil amendment included three variants: control with pure combustion waste, admixture of lignite culm and addition of acid sand. Both alder species displayed good growth parameters comparable to those of alders in natural habitats. However, black alder had better growth parameters, such as stand density index (SDI), diameter at breast height (DBH) and height (H) than grey alder. The lignite amendment exerted a positive effect on tree growth, reflected in a higher SDI and H, whereas the acid sand amendment did not affect any of the growth parameters of the studied alder species. Despite the good growth parameters, the measured N:P and N:K ratios in the alder leaves largely differed from the optimal values indicating insufficient P and K supply at the combustion waste disposal site. This may pose a threat to further development of the introduced tree plantings. The introduction of alders along with the lignite addition into the planting holes seems to be a successful method of combustion waste revegetation.
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Torabian, Shahram; Farhangi-Abriz, Salar; Rathjen, Judith
2018-05-31
This research was conducted to evaluate effects of biochar (50 and 100 g kg -1 soil) and lignite (50 and 100 g kg -1 soil) treatments on H + -ATPase and H + -PPase activity of root tonoplast, nutrient content, and performance of mung bean under salt stress. High saline conditions increased H + -ATPase and H + -PPase activities in root tonoplast, sodium (Na) content, reactive oxygen species (H 2 O 2 and O 2 - ) generation, relative electrolyte leakage (REL) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) activity in root and leaf, but decreased relative water content (RWC), chlorophyll content index, leaf area, potassium (K), calcium (Ca), magnesium (Mg), zinc (Zn) and iron (Fe) content of plant tissues, root and shoot dry weight of mung bean. Lignite and biochar treatments decreased the H + -ATPase and H + -PPase activities of root tonoplast under salt stress. Moreover, these treatments increased the cation exchange capacity of soil and nutrient values in plant tissues. Biochar and lignite diminished the generation of reactive oxygen species and DPPH activity in root and leaf cells, and these superior effects improved chlorophyll content index, leaf area and growth of mung bean under both conditions. In general, the results of this study demonstrated that biochar and lignite decreased the entry of Na ion into the cells, enriched plant cells with nutrients, and consequently improved mung bean performance under salt toxicity. Copyright © 2018 Elsevier Masson SAS. All rights reserved.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson, C.M.; DeWall, R.A.; Ljubicic, B.R.
1994-03-01
Yugoslavia`s interest in lignite-water fuel (LWF) stems from its involvement in an unusual power project at Kovin in northern Serbia. In the early 1980s, Electric Power of Serbia (EPS) proposed constructing a 600-MW power plant that would be fueled by lignite found in deposits along and under the Danube River. Trial underwater mining at Kovin proved that the dredging operation is feasible. The dredging method produces a coal slurry containing 85% to 90% water. Plans included draining the water from the coal, drying it, and then burning it in the pulverized coal plant. In looking for alternative ways to utilizemore » the ``wet coal`` in a more efficient and economical way, a consortium of Yugoslavian companies agreed to assess the conversion of dredged lignite into a LWF using hot-water-drying (HWD) technology. HWD is a high-temperature, nonevaporative drying technique carried out under high pressure in water that permanently alters the structure of low-rank coals. Changes effected by the drying process include irreversible removal of moisture, micropore sealing by tar, and enhancement of heating value by removal of oxygen, thus, enhancement of the slurry ability of the coal with water. Physical cleaning results indicated a 51 wt % reduction in ash content with a 76 wt % yield for the lignite. In addition, physical cleaning produced a cleaned slurry that had a higher attainable solids loading than a raw uncleaned coal slurry. Combustion studies were then performed on the raw and physically cleaned samples with the resulting indicating that both samples were very reactive, making them excellent candidates for HWD. Bench-scale results showed that HWD increased energy densities of the two raw lignite samples by approximately 63% and 81%. An order-of-magnitude cost estimate was conducted to evaluate the HWD and pipeline transport of Kovin LWF to domestic and export European markets. Results are described.« less
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NASA Astrophysics Data System (ADS)
Cooper, Anne Marie
This study investigates the effect of the virgin granular activated carbon (GAC) on the properties of synthesized iron (hydr)oxide nanoparticles impregnated GAC (Fe-GAC) media and its ability to remove arsenate and organic trichloroethylene (TCE) from water. Fe-GAC media were synthesized from bituminous and lignite-based virgin GAC via three variations of a permanganate/Fe(II) synthesis method. Data obtained from an array of characterization techniques indicated that differences in pore size distribution and surface chemistry of the virgin GAC favor different reaction paths for the iron (hydr)oxide nanoparticles formation. Batch equilibrium isotherm testing (120 microg-As/L; 6 mg-TCE/L, 10 mM NaHCO3 at pH = 7.2 +/- 0.1 and pH = 8.2 +/- 0.1) showed arsenic removal capability was increased as a result of iron (nanoparticles) impregnation, while TCE removal properties were decreased in Fe-GAC media. This tradeoff was displayed by both lignite and bituminous Fe-GAC but was most pronounced in lignite-based Fe-GAC having the highest Fe content (13.4% Fe) which showed the most favorable Freundlich adsorption and intensity parameters for arsenic of Ka = 72.6 (microg-As/g-FeGAC)(L/microg-As)1/n, 1/n = 0.6; and least favorable adsorption for TCE of Ka = 0.8 (mg-TCE/g-FeGAC)(L/mg-TCE)1/n, 1/n = 4.47. It was concluded that iron content was the main factor contributing to enhanced arsenic removal and that this was affected by base GAC properties such as pore size distribution and surface functional groups. However high Fe content can result in pore blockage; reduction in available adsorption sites for organic co-contaminants; and have a significant effect on the Fe-GACs overall adsorption capacity.
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30 CFR 75.1319 - Weight of explosives permitted in boreholes in bituminous and lignite mines.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Weight of explosives permitted in boreholes in bituminous and lignite mines. 75.1319 Section 75.1319 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... 3 pounds except when blasting solid rock in its natural deposit. (b) The total weight of explosives...
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30 CFR 75.1319 - Weight of explosives permitted in boreholes in bituminous and lignite mines.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Weight of explosives permitted in boreholes in bituminous and lignite mines. 75.1319 Section 75.1319 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... 3 pounds except when blasting solid rock in its natural deposit. (b) The total weight of explosives...
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30 CFR 75.1319 - Weight of explosives permitted in boreholes in bituminous and lignite mines.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Weight of explosives permitted in boreholes in bituminous and lignite mines. 75.1319 Section 75.1319 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... 3 pounds except when blasting solid rock in its natural deposit. (b) The total weight of explosives...
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30 CFR 75.1319 - Weight of explosives permitted in boreholes in bituminous and lignite mines.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Weight of explosives permitted in boreholes in bituminous and lignite mines. 75.1319 Section 75.1319 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... 3 pounds except when blasting solid rock in its natural deposit. (b) The total weight of explosives...
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30 CFR 75.1319 - Weight of explosives permitted in boreholes in bituminous and lignite mines.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Weight of explosives permitted in boreholes in bituminous and lignite mines. 75.1319 Section 75.1319 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... 3 pounds except when blasting solid rock in its natural deposit. (b) The total weight of explosives...
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Keighin, C.W.; Flores, R.M.; Ochs, A.
In southwestern North Dakota, minable lignite beds in the Paleocene Fort Union Formation include the Harmon and Hansen beds in the Bowman-Gascoyne area. Data from more than 700 drill holes penetrating these beds was used to construct stratigraphic cross sections. The Harmon and Hansen beds are the thickest and most laterally persistent lignites found under < 150 ft of overburden. The Harmon coal bed is as much as 34 ft thick, and is often split by claystone interbeds of variable thickness. The Hansen coal bed typically occurs 10--100 ft below the Harmon coal bed; it rarely attains a thickness ofmore » 15 ft, and averages 4 ft in thickness.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Korkmaz, S.; Kara-Gulbay, R.; Turan, M.
Since Turkey is a developing country with tremendous economic growth, its energy demand is also getting increased. Of this energy, about 70% is supplied from fossil fuels and the remaining 30% is from renewable sources. Among the fossil fuels, 90% of oil, natural gas, and coal are imported, and only 10% is from domestic sources. All the lignite is supplied from domestic sources. The total share of renewable sources and lignite in the total energy production is 45%. In order for Turkey to have sufficient and reliable energy sources, first the renewable energy sources must be developed, and energy productionmore » from fossil fuels, except for lignite, must be minimized. Particularly, scarcity of fossil fuels and increasing oil prices have a strong effect on economic growth of the country.« less
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Olea, Ricardo A.; Luppens, James A.
2015-01-01
Coal is a chemically complex commodity that often contains most of the natural elements in the periodic table. Coal constituents are conventionally grouped into four components (proximate analysis): fixed carbon, ash, inherent moisture, and volatile matter. These four parts, customarily measured as weight losses and expressed as percentages, share all properties and statistical challenges of compositional data. Consequently, adequate modeling should be done in terms of a logratio transformation, a requirement that is commonly overlooked by modelers. The transformation of choice is the isometric logratio transformation because of its geometrical and statistical advantages. The modeling is done through a series of realizations prepared by applying sequential simulation for the purpose of displaying the parts in maps incorporating uncertainty. The approach makes realistic assumptions and the results honor the data and basic considerations, such as percentages between 0 and 100, all four parts adding to 100% at any location in the study area, and a style of spatial fluctuation in the realizations equal to that of the data. The realizations are used to prepare different results, including probability distributions across a deposit, E-type maps displaying average properties, and probability maps summarizing joint fluctuations of several parts. Application of these maps to a lignite bed clearly delineates the deposit boundary, reveals a channel cutting across, and shows that the most favorable coal quality is to the north and deteriorates toward the southeast.
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NASA Astrophysics Data System (ADS)
Schillem, Steffi; Schneider, Bernd-Uwe; Zeihser, Uwe; Hüttl, Reinhard F.
2017-04-01
Land degradation is recognized as the main environmental problem that adversely depletes soil organic carbon (SOC) and nitrogen (SON) stocks, which in turn directly affects the fertility and productivity of soils. Degraded soils and marginal lands are characterized by low fertility, poor physicochemical and biological properties and are almost free of soil organic matter (SOM), limiting their functional properties and, hence, their productivity. To enhance or restore the fertility of these soils, natural soil amendments such as biochar, lignite or humic acids can be added. A greenhouse experiment was carried out to investigate the effect of different application rates (5, 7.5, 11, 15, 28 t ha-1) of N-modified lignite (NL) incorporated in a nutrient-poor sandy soil from a recultivation site on plant growth, water use and nitrogen use efficiency of summer wheat. Additionally activated biochar (BC) was tested to see whether any differences exist between N-modified lignite and activated biochar at the same C-application rates. All variants with soil amendments displayed a much higher grain and straw yield and water use efficiency compared to the control sample. The differences were significant for the 28 t ha-1variant followed by the variant with 5 t ha-1 NL. With the 7.5 t ha-1 NL higher biomasses, water and nitrogen use efficiency could be achieved compared to the variant treated with BC at the same C-content. This study shows that even small amounts of N-modified lignite can increase growth, water and nitrogen use efficiency of summer wheat on marginal lands.
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Stripping-coal deposits on lower Lignite Creek, Nenana coal field, Alaska
Wahrhaftig, Clyde; Birman, Joseph H.
1954-01-01
Stripping-coal reserves in an area of about 9.4 square miles extending from the Nenana River about 6 miles up the valley of Lignite Creek are estimated to amount to about 95, 000, 000 tons. The stripping-coal reserves are located in the lower and middle members of the Tertiary coal-bearing formation. Five continuous beds in the middle member range in thickness from 5 to 30 feet, and a discontinuous bed at the base of the lower member is about 60 feet thick. Analyses of outcrop samples, as received at the laboratory, show a heating content of 7,500--8,200 Btu, an ash content of 6 to 14 percent, and a moisture content of 25 percent. The reserve estimate is based on a maximum thickness of overburden of 200 feet. Coal below the level of Lignite Creek or its major tributaries was not considered as it was assumed that stripping would be by hydraulic methods. Uncertainties regarding the position of the coal outcrops and the extent of burning of the coal beds are the basis for a recommendation that, where possible, the stripping reserves be tested by drilling. Overburden consists largely of weakly consolidated sandstone and includes some coarse gravel and a few boulders 20 feet or more in diameter. Water for hydraulic mining can be obtained from the Nenana River. Lignite Creek does not appear to be a dependable source. Disposal of debris may affect the channel of the Nenana River causing damage to railroads and structures. Landslides are common in the valley of Lignite Creek and will affect mining operations and transportation routes.
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Warwick, Peter D.; Aubourg, Claire E.; Willett, Jason C.
1999-01-01
The coal-bearing Gulf of Mexico Coastal Plain of North America contains a variety of depositional settings and coal types. The coal-bearing region extends westward from Alabama and Mississippi, across Louisiana to the northern part of the Mississippi Embayment, and then southward to eastern Arkansas, Texas and northern Mexico (fig. 1). Most of the coal currently mined in Texas is lignite from the upper part of the Wilcox Group (Paleocene-Eocene) and, in Louisiana, lignite is mined from the lower part of the Wilcox (fig. 2). Gulf Coast coal is used primarily as fuel for mine-mouth electric plants. On this field trip we will visit the only two non-Wilcox coal mining intervals in the Texas-Louisiana Coastal Plain; these include the San Pedro - Santo Tomas bituminous cannel-like coal zone of the Eocene Claiborne Group, and the San Miguel lignite coal zone of the Eocene Jackson Group (fig. 2). Other coal-mining areas in northern Mexico are currently producing bituminous coal from the Cretaceous Olmos Formation of the Navaro Group (fig. 2).
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Comparison of metallurgical coke and lignite coke for power generation in Thailand
NASA Astrophysics Data System (ADS)
Ratanakuakangwan, Sudlop; Tangjitsitcharoen, Somkiat
2017-04-01
This paper presents and compares two alternatives of cokes in power generation which are the metallurgical coke with coke oven gas and the coke from lignite under the consideration of the energy and the environment. These alternatives not only consume less fuel due to their higher heat content than conventional coal but also has less SO2 emission. The metallurgical coke and its by-product which is coke oven gas can be obtained from the carbonization process of coking coal. According to high grade coking coal, the result in the energy attitude is not profitable but its sulfur content that directly affects the emission of SO2 is considered to be very low. On the other hand, the coke produced from lignite is known as it is the lowest grade from coal and it causes the high pollution. Regarding to energy profitability, the lignite coke is considered to be much more beneficial than the metallurgical coke in contrast to the environmental concerns. However, the metallurgical coke has the highest heating value. Therefore, a decision making between those choices must be referred to the surrounding circumstances based on energy and environment as well as economic consideration in the further research.
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NASA Astrophysics Data System (ADS)
Rao, M. R.; Sahni, Ashok; Rana, R. S.; Verma, Poonam
2013-04-01
Early Eocene sedimentary successions of south Asia, are marked by the development of extensive fossil-bearing, lignite-rich sediments prior to the collision of India with Asia and provide data on contemporary equatorial faunal and vegetational assemblages. One such productive locality in western India is the Vastan Lignite Mine representing approximately a 54-52 Ma sequence dated by the presence of benthic zone marker species, Nummulites burdigalensis burdigalensis. The present study on Vastan Lignite Mine succession is based on the spore-pollen and dinoflagellate cyst assemblages and documents contemporary vegetational changes. 86 genera and 105 species belonging to algal remains (including dinoflagellate cysts), fungal remains, pteridophytic spores and angiospermous pollen grains have been recorded. On the basis of first appearance, acme and decline of palynotaxa, three cenozones have been recognized and broadly reflect changing palaeodepositional environments. These are in ascending stratigraphic order (i) Proxapertites Spp. Cenozone, (ii) Operculodinium centrocarpum Cenozone and (iii) Spinizonocolpites Spp. Cenozone. The basal sequence is lagoonal, palm-dominated and overlain by more open marine conditions with dinoflagellate cysts and at the top, mangrove elements are dominant. The succession has also provided a unique record of fish, lizards, snakes, and mammals.
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Maharaj, S V M
2014-01-01
Background: Balkan endemic nephropathy (BEN) is a chronic, tubulointerstitial renal disease often accompanied by urothelial cancer that has a lethality of nearly 100%. Introduction: One of the many factors that have been proposed to play an etiological role in BEN is exposure to organic compounds from Pliocene lignite coal deposits via the drinking water in endemic areas. Objectives: The objective of this study was to systematically evaluate the role of the tenets of the Pliocene lignite hypothesis in the etiology of BEN in order to provide an improved understanding of the hypothesis for colleagues and patients alike. Methods: A comprehensive compilation of the possible limitations of the hypothesis, with each limitation addressed in turn is presented. Results: The Pliocene lignite hypothesis can best account for, is consistent with, or has the potential to explain the evidence associated with the myriad of factors related to BEN. Conclusions: Residents of endemic areas are exposed to complex mixtures containing hundreds of organic compounds at varying doses and their potentially more toxic (including nephrotoxic) and/or carcinogenic metabolites; however, a multifactorial etiology of BEN appears most likely. PMID:24075451
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A geochemical study of macerals from a Miocene lignite and an Eocene bituminous coal, Indonesia
Stankiewicz, B.A.; Kruge, M.A.; Mastalerz, Maria
1996-01-01
Optical and chemical studies of maceral concentrates from a Miocene lignite and an Eocene high-volatile bituminous C coal from southeastern Kalimantan, Indonesia were undertaken using pyro-Lysis, optical, electron microprobe and FTIR techniques Pyrolysis products of vitrinite from bituminous coal were dominated by straight-chain aliphatics and phenols. The huminite of the Miocene lignite produced mostly phenolic compounds upon pyrolysis. Differences in the pyrolysis products between the huminite and vitrinite samples reflect both maturation related and paleobotanical differences. An undefined aliphatic source and/or bacterial biomass were the likely contributors of n-alkyl moieties to the vitrinite. The resinite fraction in the lignite yielded dammar-derived pyrolysis products, as well as aliphatics and phenols as the products of admixed huminite and other liptinites. The optically defined resinite-rich fraction of the bituminous coal from Kalimantan produced abundant n-aliphatic moieties upon pyrolysis, but only two major resin markers (cadalene and 1,6-dimethylnaphthalene). This phenomenon is likely due to the fact that Eocene resins were not dammar-related. Data from the electron microprobe and Fourier transform infrared spectrometry strongly support the results obtained by Py GC MS and microscopy.
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Survey of synfuel technology for lignite
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sondreal, E.A.
1982-01-01
The most important market for lignite will continue to be the electric utility industry, where it is used to fuel large pc-fired boilers serving major regional power grids. However, the growth of this market and thechnology is being challenged by new and more stringent environmental control requirements, including the international concern over acid rain. Environmental and economic issues could either encourage or limit the development of a synfuels market for lignite depending on the cost effectiveness of the technological solutions that are developed. Clearly the United States needs to develop its coal resources to reduce dependence on imported oil. However,more » demand for coal derived substitute petroleum will be constrained by cost for the forseeable future. Government policy initiatives and new technology will be the keys to removing these constraints in the decades ahead. A crossover point with respect to petroleum and natural gas will be reached at some point in the future, which will allow synthetic fuels to penetrate the markets now served by oil and gas. Those of us who are today concerned with the development of lignite resources can look forward to participating in the major synfuels market that will emerge when those economic conditions are realized.« less
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Beneficiation of Turkish lignites by thermal treatment and magnetic separation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Onal, G.; Renda, D.; Mustafaev, I.
1999-07-01
In this paper, the improvement of Turkish lignites by semi-coking and REMS magnetic separation, in two stages, is discussed. The oxidation and decomposition of pyrite through the thermal treatment result in the formation of iron oxide and pyrrhotite on the surface. In addition to pyrite, part of the organic sulfur is also removed. After thermal treatment of lignites at temperatures ranging from 370 to 650 C, the application of REMS magnetic separator produces a product higher in calorific value and lower in sulfur content. The product can be utilized after briquetting. The volatile gases can also be used after sulfurmore » removal. This process appears to be feasible as a clean coal manufacture from the point of energy efficiency. A short economic analysis is also presented.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Vorres, K S
The overall accomplishments of the HYGAS program to date are that it has demonstrated the key process concepts and integrated unit operations of coal gasification. It has also demonstrated several methods of hydrogen generation, including catalytic steam reforming of natural gas, electrothermal gasification, and also steam-oxygen gasification. A total of 37 tests with lignite, including a total of 5500 tons of lignite processed, demonstrated the technical feasibility of a gasification process using lignite. A total of 17 tests with bituminous coal involved a total of 3100 tons. Some specific objectives of the HYGAS program for fiscal 1977 include tests tomore » be conducted with subbituminous coal. Data will be collected for use in the design of an effluent treatment and water reuse cycles in a commercial plant. New methanation catalysts will be tested. Materials testing will continue.« less
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Study on coal char ignition by radiant heat flux.
NASA Astrophysics Data System (ADS)
Korotkikh, A. G.; Slyusarskiy, K. V.
2017-11-01
The study on coal char ignition by CO2-continuous laser was carried out. The coal char samples of T-grade bituminous coal and 2B-grade lignite were studied via CO2-laser ignition setup. Ignition delay times were determined at ambient condition in heat flux density range 90-200 W/cm2. The average ignition delay time value for lignite samples were 2 times lower while this difference is larger in high heat flux region and lower in low heat flux region. The kinetic constants for overall oxidation reaction were determined using analytic solution of simplified one-dimensional heat transfer equation with radiant heat transfer boundary condition. The activation energy for lignite char was found to be less than it is for bituminous coal char by approximately 20 %.
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This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.
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U.S. sulfur dioxide emission reductions: Shifting factors and a carbon dioxide penalty
Brown, Marilyn Ann; Li, Yufei; Massetti, Emanuele; ...
2017-01-18
For more than 20 years, the large-scale application of flue gas desulfurization technology has been a dominant cause of SO 2 emission reductions. From 1994–2004, electricity generation from coal increased, but the shift to low-sulfur coal eclipsed this. From 2004–2014, electricity generation from coal decreased, but a shift to higher-sulfur subbituminous and lignite coal overshadowed this. Here, the shift in coal quality has also created a CO 2 emissions penalty, representing 2% of the sector’s total emissions in 2014.
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Processes for liquefying carbonaceous feedstocks and related compositions
MacDonnell, Frederick M.; Dennis, Brian H.; Billo, Richard E.; Priest, John W.
2017-02-28
Methods for the conversion of lignites, subbituminous coals and other carbonaceous feedstocks into synthetic oils, including oils with properties similar to light weight sweet crude oil using a solvent derived from hydrogenating oil produced by pyrolyzing lignite are set forth herein. Such methods may be conducted, for example, under mild operating conditions with a low cost stoichiometric co-reagent and/or a disposable conversion agent.
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Enhancing Carbon Reactivity in Mercury Control in Lignite-Fired Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chad Wocken; Michael Holmes; John Pavlish
2008-06-30
This project was awarded through the U.S. Department of Energy (DOE) National Energy Technology Laboratory Program Solicitation DE-PS26-03NT41718-01. The Energy & Environmental Research Center (EERC) led a consortium-based effort to resolve mercury (Hg) control issues facing the lignite industry. The EERC team-the Electric Power Research Institute (EPRI); the URS Corporation; the Babcock & Wilcox Company; ADA-ES; Apogee; Basin Electric Power Cooperative; Otter Tail Power Company; Great River Energy; Texas Utilities; Montana-Dakota Utilities Co.; Minnkota Power Cooperative, Inc.; BNI Coal Ltd.; Dakota Westmoreland Corporation; the North American Coal Corporation; SaskPower; and the North Dakota Industrial Commission-demonstrated technologies that substantially enhanced themore » effectiveness of carbon sorbents to remove Hg from western fuel combustion gases and achieve a high level ({ge} 55% Hg removal) of cost-effective control. The results of this effort are applicable to virtually all utilities burning lignite and subbituminous coals in the United States and Canada. The enhancement processes were previously proven in pilot-scale and limited full-scale tests. Additional optimization testing continues on these enhancements. These four units included three lignite-fired units: Leland Olds Station Unit 1 (LOS1) and Stanton Station Unit 10 (SS10) near Stanton and Antelope Valley Station Unit 1 (AVS1) near Beulah and a subbituminous Powder River Basin (PRB)-fired unit: Stanton Station Unit 1 (SS1). This project was one of three conducted by the consortium under the DOE mercury program to systematically test Hg control technologies available for utilities burning lignite. The overall objective of the three projects was to field-test and verify options that may be applied cost-effectively by the lignite industry to reduce Hg emissions. The EERC, URS, and other team members tested sorbent injection technologies for plants equipped with electrostatic precipitators (ESPs) and spray dryer absorbers combined with fabric filters (SDAs-FFs). The work focused on technology commercialization by involving industry and emphasizing the communication of results to vendors and utilities throughout the project.« less
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Characteristics of Pyrolytic Topping in Fluidized Bed for Different Volatile Coals
NASA Astrophysics Data System (ADS)
Xiong, R.; Dong, L.; Xu, G. W.
Coal is generally combusted or gasified directly to destroy completely the chemical structures, such as aromatic rings containing in volatile coals including bituminite and lignite. Coal topping refers to a process that extracts chemicals with aromatic rings from such volatile coals in advance of combustion or gasification and thereby takes advantage of the value of coal as a kind of chemical structure resource. CFB boiler is the coal utilization facility that can be easily retrofitted to implement coal topping. A critical issue for performing coal topping is the choice of the pyrolytic reactor that can be different types. The present study concerns fluidized bed reactor that has rarely been tested for use in coal topping. Two different types of coals, one being Xiaolongtan (XLT) lignite and the other Shanxi (SX) bituminous, were tested to clarify the yield and composition of pyrolysis liquid and gas under conditions simulating actual operations. The results showed that XLT lignite coals had the maximum tar yield in 823-873K and SX bituminite realized its highest tar yield in 873-923K. Overall, lignite produced lower tar yield than bituminous coal. The pyrolysis gas from lignite coals contained more CO and CO2 and less CH4, H2 and C2+C3 (C2H4, C2H6, C3H6, C3H8) components comparing to that from bituminous coal. TG-FTIR analysis of tars demonstrated that for different coals there are different amounts of typical chemical species. Using coal ash of CFB boiler, instead of quartz sand, as the fluidized particles decreased the yields of both tar and gas for all the tested coals. Besides, pyrolysis in a reaction atmosphere simulating the pyrolysis gas (instead of N2) resulted also in higher production of pyrolysis liquid.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Cronauer, D.C.; Swanson, A.J.; Sajkowski, D.J.
Research under way in this project centers upon developing and evaluating catalysts and process improvements for coal liquefaction in the two-stage close-coupled catalytic process. As documented in the previous quarterly report there was little advantage for presoaking Black Thunder coal or Martin Lake lignite in a hydrogen-donor solvent, such as tetralin, at temperatures up to 600{degrees}F prior to liquefaction at higher temperatures. The amount of decarboxylation that occurred during the presoaking of Black Thunder coal or Martin Lake lignite in tetralin in the temperature range of 400 to 600{degrees}F was also relatively small. As indicated by both CO{sub 2} releasemore » and the change in oxygen-containing coal functionality, the level of decarboxylation in coal-derived solvent seems to correlate with the depth of coal dissolution. The feedstock liquefaction studies for the three feedstocks (Black Thunder subbituminous coal, Martin Lake lignite, and Illinois No. 6 coal) have been completed, and their results were compared in this report. Both Black Thunder coal and Martin Lake lignite gave lighter products than Illinois No. 6 coal at similar process conditions. Severe catalyst deactivation in the first stage was also observed with the Martin Lake lignite run. The first stage catalyst testing program was started. After a successful reference run with Illinois No. 6 coal, a high temperature run with AMOCAT{trademark} 1C was completed. In addition, a run was made with Illinois No. 6 coal using an oil-soluble catalyst, Molyvan L, in the first stage and AMOCAT{trademark} 1C in the second stage, where preliminary run results look promising.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, R.L.
A literature survey was conducted in order to determine the amount of information available to the public concerning the impact of the Resource Conservation and Recovery Act of 1976 (RCRA) on the use or disposal of solid wastes from Texas lignite-fired utility boilers. The utility power plants of ALCOA, Big Brown, Martin Lake, Monticello and San Miguel are the only facilities currently using Texas lignite as fuel. RCRA is a comprehensive federal law which provides for the management of hazardous waste from generation to ultimate disposal. Utility solid wastes such as fly ash and flue gas desulfurization (FGD) sludge aremore » currently classified as excluded wastes (wastes exempt from hazardous classification) pending further information regarding these high-volume, low risk wastes. RCRA also provides for the increased need of recovered materials in Subtitle F - Federal Procurement. The lignite deposits of Texas occur in belts that stretch diagonally across the state from Laredo to Texarkana. The sulfur content and Btu value of Texas lignite combined requires that sulfur scrubbers be installed on new power plant units. The utility solid wastes occur in large quantities and leachate from some of these wastes contained detectable amounts of chromium and selenium. However, the concentration of these elements in the leachate was not sufficient to classify any of the utility wastes in this study as hazardous per current RCRA guidelines. In general, fly ash and FGD sludge are classified as Class II wastes and disposed of in an environmentally acceptable manner. Considerable amounts of bottom ash and fly ash are utilized but, thus far, FGD sludge has been landfilled, usually in combination with fly ash.« less
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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.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Iisa, Kristiina
2016-04-06
NREL will work with Participant as a subtier partner under DE-FOA-0000240 titled "Co-Production of Power, Fuels, and Chemicals via Coal/Biomass Mixtures." The goal of the project is to determine the gasification characteristics of switchgrass and lignite mixtures and develop kinetic models. NREL will utilize a pressurized thermogravimetric analyzer to measure the reactivity of chars generated in a pressurized entrained-flow reactor at Participant's facilities and to determine the evolution of gaseous species during pyrolysis of switchgrass-lignite mixtures. Mass spectrometry and Fourier-transform infrared analysis will be used to identify and quantify the gaseous species. The results of the project will aid inmore » defining key reactive properties of mixed coal biomass fuels.« less
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The effects of pore structure on the behavior of water in lignite coal and activated carbon.
Nwaka, Daniel; Tahmasebi, Arash; Tian, Lu; Yu, Jianglong
2016-09-01
The effects of physical structure (pore structure) on behavior of water in lignite coal and activated carbon (AC) samples were investigated by using Differential Scanning Calorimetry (DSC) and low-temperature X-ray diffraction (XRD) techniques. AC samples with different pore structures were prepared at 800°C in steam and the results were compared with that of parent lignite coal. The DSC results confirmed the presence of two types of freezable water that freeze at -8°C (free water) and -42°C (freezable bound water). A shift in peak position of free water (FW) towards lower temperature was observed in AC samples compared to the lignite coal with decreasing water loading. The amount of free water (FW) increased with increasing gasification conversion. The amounts of free and freezable bound water (FBW) in AC samples were calculated and correlated to pore volume and average pore size. The amount of FW in AC samples is well correlated to the pore volume and average pore size of the samples, while an opposite trend was observed for FBW. The low-temperature XRD analysis confirmed the existence of non-freezable water (NFW) in coal and AC with the boundary between the freezable and non-freezable water (NFW) determined. Copyright © 2016 Elsevier Inc. All rights reserved.
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NASA Astrophysics Data System (ADS)
Mulder, Christian; Sakorafa, Vasiliki; Burragato, Francesco; Visscher, Henk
2000-06-01
A consensus about the development of freshwater wetlands in relation to time and space is urgently required. Our study aims to address this issue by providing additional data for a fine-scaled comparison of local depositional settings of Greek mires during the Pliocene and Pleistocene. Lignite profiles exhibit phytogenic organic components (macerals) that have been used to investigate the past peat-forming vegetation structure and their succession series. The organic petrology of lignite samples from the opencast mines of Komanos (Ptolemais) and Choremi (Megalopolis) was achieved to assess the water supply, wetland type, nutrient status and vegetation physiognomy. A holistic approach (a study of ecosystems as complete entities) was carried out for a paleoecological reconstruction of the mires. Huminite, liptinite and inertinite were traced by means of their chemical and morphological differences together with the morphogenic and taphonomic affinities. The problem of combining independent information from different approaches in a multivariate calibration setup has been considered. Linear regression, non-metric multidimensional scaling and one-way analysis of variance tested the occurrence of palynological and petrological proxies. Although the lignite formation and deposition are less related to humid periods than expected, the resulting differences occurring in the reconstructed development stages appear to be related to astronomically forced climate fluctuations.
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Kosior, Grzegorz; Samecka-Cymerman, Aleksandra; Kolon, Krzysztof; Brudzińska-Kosior, Anna; Bena, Waldemar; Kempers, Alexander J
2015-07-01
Intensive lignite and glass sand mining and industrial processing release waste which may contain elements hazardous to the aquatic ecosystem and constitute a potential risk to human health. Therefore, their levels must be carefully controlled. As a result, we examined the effects of sewage on the aquatic Fontinalis antipyretica moss in the Nysa Łużycka (lignite industry) and the Kwisa Rivers (glass sand industry). The Nysa Łużycka and the Kwisa Rivers appeared to be heavily polluted with As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn, which were reflected in the extremely high concentration of these elements in F. antipyretica along the studied watercourses. In the Nysa Łużycka, trace element composition in the moss species is affected by lignite industry with accumulation in its tissues of the highest concentrations of Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn, while samples from the Kwisa sites influenced by glass sand industry revealed the highest concentrations of As, V and Fe. The principal component and classification analysis classifies the concentration of elements in the aquatic F. antipyretica moss, thus enabling the differentiation of sources of water pollution in areas affected by mining industry.
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Effect of co-combustion on the burnout of lignite/biomass blends: a Turkish case study.
Haykiri-Acma, H; Yaman, S
2008-11-01
Co-combustion of Turkish Elbistan lignite and woody shells of hazelnut was performed in a TGA up to 1173 K with a heating rate of 20 K/min. SEM images of each fuel revealed the differences in their physical appearances. Hazelnut shell was blended with lignite in the range of 2-20 wt% to observe the co-combustion properties. Maximum burning rates (Rmax), temperatures of the maximum burning rates (T(R-max)), and the final burnout values of the parent samples and the blends were compared. The results were interpreted considering lignite properties and the major biomass ingredients such as cellulosics, hemicellulosics, and lignin. Deviations between the theoretical and experimental burnout values were evaluated at various temperatures. Burnout characteristics of the blends up to 10 wt% were concluded to have a synergistic effect so the addition of hazelnut shell up to 8 wt% provided higher burnouts than the expected theoretical ones, whereas addition of as much as 10 wt% led to a decrease in the burnout. However, the additive effects were more favorable for the blend having a biomass content of 20 wt%. Apparent activation energy, Rmax, and T(R-max), were found to follow the additive behavior for the blend samples.
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Thermal exploitation of wastes with lignite for energy production.
Grammelis, Panagiotis; Kakaras, Emmanuel; Skodras, George
2003-11-01
The thermal exploitation of wastewood with Greek lignite was investigated by performing tests in a laboratory-scale fluidized bed reactor, a 1-MW(th) semi-industrial circulating fluidized bed combustor, and an industrial boiler. Blends of natural wood, demolition wood, railroad sleepers, medium-density fiberboard residues, and power poles with lignite were used, and the co-combustion efficiency and the effect of wastewood addition on the emitted pollutants were investigated. Carbon monoxide, sulfur dioxide, and oxides of nitrogen emissions were continuously monitored, and, during the industrial-scale tests, the toxic emissions (polychlorinated dibenzodioxins and dibenzofurans and heavy metals) were determined. Ash samples were analyzed for heavy metals in an inductively coupled plasma-atomic emission spectroscopy spectrophotometer. Problems were observed during the preparation of wastewood, because species embedded with different compounds, such as railway sleepers and demolition wood, were not easily treated. All wastewood blends were proven good fuels; co-combustion proceeded smoothly and homogeneous temperature and pressure profiles were obtained. Although some fluctuations were observed, low emissions of gaseous pollutants were obtained for all fuel blends. The metal element emissions (in the flue gases and the solid residues) were lower than the legislative limits. Therefore, wastewood co-combustion with lignite can be realized, provided that the fuel handling and preparation can be practically performed in large-scale installations.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Cronauer, D.C.; Swanson, A.J.; Sajkowski, D.J.
Research under way in this project centers upon developing and evaluating catalysts and process improvements for coal liquefaction in the two-stage close-coupled catalytic process. As documented in the previous quarterly report (Task 3.1), there was little advantage for presoaking Black Thunder coal or Martin Lake lignite in a hydrogen-donor solvent, such as tetralin, at temperatures up to 600{degrees}F prior to liquefaction at higher temperatures. The amount of decarboxylation that occurred during the presoaking of Black Thunder coal or Martin Lake lignite in tetralin in the temperature range of 400 to 600{degrees}F was also relatively small. Further experimentation was undertaken inmore » a continuous flow unit with Black Thunder coal, where the primary goal was to determine the extent of decarboxylation and changes in the structure of the unconverted coal samples. The preliminary results indicated little conversion of the feed coal to THF solubles at 600{degrees}F, although the conversion did increase with increasing temperature up to 24% at 700{degrees}F. The level of decarboxylation was also low at the above reaction temperatures. Thus, presoaking in a coal-derived solvent or even tetralin does not seem to be an effective means to achieve decarboxylation. A suitable sample of Illinois No. 6 coal was received and tested for liquefaction. The batch liquefaction showed that this sample had good reactivity. The continuous liquefaction test was done in a two-stage unit with AMOCAT{trademark}-1C catalyst in both reactors. A significant amount of resid was produced throughout this three-week run. As the catalyst aged, the distillate production decreased and its product quality got worse. The feedstock liquefaction studies for the three feedstocks (Black Thunder subbituminous coal, Martin Lake lignite, and Illinois No. 6 coal) have been completed, and their results will be compared in a subsequent quarterly report.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Gueyagueler, T.; Karaman, H.
1995-12-31
In this paper fires due to spontaneous combustion in Middle Anatolian Lignite mine (OAL) which is the first fully mechanized underground lignite mine in Turkey, are studied. Since the installation of mechanization, due to spontaneous heating, four panel fires namely, AO1, AO2, AO3 and AO4 have broken out. During these fires, the concentrations of carbon monoxide, methane and the velocity of air are measured continuously by the Micro Minos Environmental monitoring system. For each fire, the environment where fire has started is examined and the possible causes of the fire are investigated. Also the precautions taken to extinguish the firemore » at different stages are described and the importance of the early detection of mine fire are discussed together with the limitations of the monitoring system the practical difficulties observed during the fire.« less
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NASA Astrophysics Data System (ADS)
Aydan, Ö.; Ito, T.
2015-11-01
It is well known that some sinkholes or subsidence take place from time to time in the areas where abandoned room and pillar type mines exist. The author has been involved with the stability of abandoned mines beneath urbanized residential areas in Tokai region and there is a great concern about the stability of these abandoned mines during large earthquakes as well as in the long term. The 2003 Miyagi Hokubu and 2011 Great East Japan earthquakes caused great damage to abandoned mines and resulted in many collapses. The author presents the effect of the depth and groundwater on the formation of sinkholes or ground subsidence associated with abandoned room and pillar lignite mines under static and dynamic conditions and discusses the implications on the areas above abandoned lignite mines in this paper.
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Production of a nitrogeneous humic fertilizer by the oxidation-ammoniation of lignite
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coca, J.
1984-12-01
Two lignite samples were oxidised with HNO/sub 3/ (20% wt) at 75 C and treated afterwards with NH/sub 3/ in a fluidised-bed reactor in a temperature range 100-375 C. The effects of temperature, NH/sub 3/ flow rate, and reaction time on the total N/sub 2/ content of the product are reported. The product contained 7-13% wt of total N/sub 2/ which increased as the ammoniation temperature increased. Soil nitrification measurements of the N/sub 2/-enriched lignites showed that the maximum conversion to nitrates and rate of nitrification are exhibited by the product obtained at the lowest ammoniation temperature, i.e. 100 C.more » Maximum conversion to nitrates at that temperature was 45%, which compares well with similar products such as ammoniated peat (35%) and ammonium nitrohumates (45%).« less
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Carbon dioxide emission factors for U.S. coal by origin and destination
Quick, J.C.
2010-01-01
This paper describes a method that uses published data to calculate locally robust CO2 emission factors for U.S. coal. The method is demonstrated by calculating CO2 emission factors by coal origin (223 counties, in 1999) and destination (479 power plants, in 2005). Locally robust CO2 emission factors should improve the accuracy and verification of greenhouse gas emission measurements from individual coal-fired power plants. Based largely on the county origin, average emission factors for U.S. lignite, subbituminous, bituminous, and anthracite coal produced during 1999 were 92.97,91.97,88.20, and 98.91 kg CO2/GJgross, respectively. However, greater variation is observed within these rank classes than between them, which limits the reliability of CO2 emission factors specified by coal rank. Emission factors calculated by destination (power plant) showed greater variation than those listed in the Emissions & Generation Resource Integrated Database (eGRID), which exhibit an unlikely uniformity that is inconsistent with the natural variation of CO2 emission factors for U.S. coal. ?? 2010 American Chemical Society.
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NASA Astrophysics Data System (ADS)
Vrabec, Mirijam; Markič, Miloš; Vrabec, Marko; Jaćimović, Radojko; Kanduč, Tjaša
2014-05-01
Lignite (organic rich) and calcified lignite (inorganic rich) samples from excavation field -50c mining area Pesje, Velenje Basin, Slovenia were investigated. During geological and structural mapping lignite and calcified lignite samples were systematically taken for determination of their petrological, geochemical and isotopic characteristics. Lignite is composed of fine detritical gelified matrix. At least five different types of calcified lignite were recognized forming laminations, calcifications after wood, petrified wood and complete replacements of lignite with carbonate. All measured parameters so far indicate geochemical processes during sedimentation of the Velenej Basin. After macroscopic description samples were split to organic and inorganic component (Ward, 1984) and powdered in an agate mortar for geochemical and isotopic analyses. Major and trace elements (As, B, Ba, Cd, Co, Cr, Cu, Hg, Mn, Mo, Sb, Se, Th, U, Zn) in these samples were determined by instrumental neutron activation analysis (INAA) using k-0 standardization method (Jaćimović et al, 2002). The isotopic composition of carbon and nitrogen was determined using a Europa 20-20 continuous flow IRMS ANCA-SL preparation module. A 1 mg amount of a sample was weighed in a tin capsule for carbon and 10 mg for nitrogen analysis. Samples for carbon analyses were pretreated with 1 M HCl to remove carbonates. Carbonate samples from carbonate-rich strata and calcified xylite were first roasted at 450 deg C (Krantz et al., 1987). Three miligrams of carbonate sample was transformed into CO2 by reaction with anhydrous H3PO4 at 55 deg C under vacuum (McCrea, 1950) and measured with GV 2003 isotope ratio mass spectrometer. Measured isotopic composition of oxygen as VPDB values was recalculated to the VSMOW reference standard to enable the comparison with data from other coal basins. SEM/EDXS of carbonate rich sediments was performed with JEOL JSM 5800 electron microanalyzer scanning electron microscope energy dispersive X-ray spectroscopy at the Department of Ceramics at the Jožef Stefan Institute. Geochemical characteristics of major and trace elements indicate that the values of major and trace elements are comparable to world average coal (Zhang et al., 2004). Isotopic composition of carbon and isotopic composition of nitrogen of investigated samples indicate values from to -29.4o to -23.7o and 1.8o to 5.9o respectively. Lower value of isotopic composition of carbon indicates higher gelification (values up to -29.4) and higher value of isotopic composition of nitrogen (values up to 5.9) indicate higher mineralization. The results of SEM/EDXS microscopy revealed that in calcified lignite chemical composition of calcite prevails. Traces of diagenetic pyrite were also found, indicating localized anoxic conditions during sedimentation. Values of isotopic composition of CCaCO3 range from -2 to +13 and indicate temperature of precipitation from 17.3 to 35 deg C, which is similar to results obtained in previous studies (Kanduč et al., 2012). References Krantz, D.E., Williams, D.F., Jones, D.S., 1987: Ecological and paleoenvironmental information using stable isotope profiles from living and fossil mollusks. Palaeogeography, Palaeoclimatology, Palaeoecology 58, 249-266. Kanduč T., Markič M., Zavšek S., McIntosh J. 2012: carbon cycling in the Pliocene Velenje Coal Basin, Slovenia, inferred from stable carbon isotopes. International Journal of Coal Geology 89, 70-83. Jaćimović, R., Lazaru, A., Mihajlović, D., Ilić, R., Stafilov, T., 2002: Determination of major and trace elements in some minerals by k0-instrumental neutron activation analysis. Journal of Radioanalytical Nuclear Chemistry, 253, 427-434. McCrea, JM., 1950. On the isotopic chemistry of carbonates and a paleotemperature scale. Journal of Chemical Physics 18, 849. Ward C.R. (Ed.), 1984: Coal Geology and Coal Technology. Black-well, Oxford, 345 pp. Zhang J.Y., Zheng C.G., Ren D.Y., Chou C.L., Zheng R.S., Wang Z.P., Zhao F. H., Ge Y.T. 2004: Distribution of potentially hazardous trace elements in coals from Shoxi provinces, China. Fuel 83: 129-135.
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Some peat deposits in Penobscot County, Maine
Cameron, Cornelia Clermont; Anderson, Walter A.
1979-01-01
Twenty of the peat deposits in Penobscot County, Maine contain an estimated 29,282,000 short tons air-dried peat. The peat is chiefly sphagnum moss and reed-sedge of high quality according to ASTM standards for agricultural and horticultural use. Analyses show that this same volume has high fuel value, low sulfur and high hydrogen contents compared with lignite and sub-bituminous coal, which may indicate that it also has potential for fuel use. On the basis of the metallic trace element content, one area within the region containing the 20 deposits has been delineated for further bedrock studies.
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Desulphurization of coal using borax
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yaman, S.; Kuecuekbayrak, S.
1996-12-31
In this study, a high sulphur Turkish lignite was mixed with various amounts of solid borax [Na{sub 2}B{sub 4}O{sub 7}10H{sub 2}O] and then these mixtures were subjected to various oxydesulphurization processes. Effects of amount of borax, temperature and partial pressure of oxygen on sulphur removal and coal recovery were investigated in the ranges of 0.625--15.000 g for 5 g lignite, 423--498 K, 0.0--1.5 MPa, respectively.
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Nicot, Jean-Philippe; Larson, Toti; Darvari, Roxana; Mickler, Patrick; Slotten, Michael; Aldridge, Jordan; Uhlman, Kristine; Costley, Ruth
2017-07-01
Understanding the source of dissolved methane in drinking-water aquifers is critical for assessing potential contributions from hydraulic fracturing in shale plays. Shallow groundwater in the Texas portion of the Haynesville Shale area (13,000 km 2 ) was sampled (70 samples) for methane and other dissolved light alkanes. Most samples were derived from the fresh water bearing Wilcox formations and show little methane except in a localized cluster of 12 water wells (17% of total) in a approximately 30 × 30 km 2 area in Southern Panola County with dissolved methane concentrations less than 10 mg/L. This zone of elevated methane is spatially associated with the termination of an active fault system affecting the entire sedimentary section, including the Haynesville Shale at a depth more than 3.5 km, and with shallow lignite seams of Lower Wilcox age at a depth of 100 to 230 m. The lignite spatial extension overlaps with the cluster. Gas wetness and methane isotope compositions suggest a mixed microbial and thermogenic origin with contribution from lignite beds and from deep thermogenic reservoirs that produce condensate in most of the cluster area. The pathway for methane from the lignite and deeper reservoirs is then provided by the fault system. © 2017, National Ground Water Association.
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Kostakis, George
2011-01-30
Slagging and fouling deposits from a pulverized lignite fired steam generating unit of the Kardia power plant (West Macedonia, Greece) were mineralogically investigated. The structure and cohesion of these deposits varied, usually depending on the level height of the boiler unit where they were formed. Some of the deposits had complex phase composition. The dominant components of the deposits of the burner zone and of the lower and intermediate boiler zones were the amorphous, anhydrite and hematite, while those of the highest levels contained amorphous, and anhydrite. Furthermore, in deposits formed in various other boiler areas gehlenite, anorthite, diopside, quartz, Ca(2)SiO(4), brownmillerite and other crystalline phases were also identified, usually in low amounts or in traces. The major part of the phases constituting the deposits were formed in the boiler, since only a minor part derived from the unreacted minerals present in lignite. Anhydrite was generated from the reaction of SO(2) with CaO formed mainly by the calcination of calcite as well as from dehydration of gypsum contained in lignite, while hematite was produced mainly from the oxidation of pyrite. The calcium-containing silicates formed in the boiler were mainly the products of reactions between CaO and minerals contained in the lignite. Copyright © 2010 Elsevier B.V. All rights reserved.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Cetincelik, M.
1979-09-01
The known occurrences of hard (bituminous) coal in Turkey are very limited. Total resources are estimated to be 1,500,000,000 metric tons of which 205,000,000 tons are considered to be technically and economically recoverable at the present time. Tertiary lignite deposits are found extensively throughout Turkey. Total resources of lignite are estimated to be about 5,140,000,000 metric tons of which 2,740,000,000 tons are considered to be recoverable. In 1978, Turkey completely nationalized its coal industry whereby the government was authorized to take over all private mines. As a result of this, a major increase in coal production is expected based onmore » a new energy policy. Turkish Coal Enterprises (TKI), a state-owned organization, is now in control of the entire coal industry. TKI was established by law in 1957 and has its headquarters in Ankara. The gradually changing structure of Turkey's national economy from agriculture to increased industrialization has been accompanied by a rise in energy requirements. However, the lack of recent industrial expansion and the decline in the national economy has been due to the shortage of energy. A new energy plan developed for the country has established that, in the future, lignite will be used in far greater proportions for electricity generation (burned in captive plants). The nationalization of Turkey's lignite mines is expected to ensure a coordinated and effective means of meeting the demand.« less
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Advanced power assessment for Czech lignite. Task 3.6, Volume 1
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sondreal, E.A.; Mann, M.D.; Weber, G.W.
1995-12-01
The US has invested heavily in research, development, and demonstration of efficient and environmentally acceptable technologies for the use of coal. The US has the opportunity to use its leadership position to market a range of advanced coal-based technologies internationally. For example, coal mining output in the Czech Republic has been decreasing. This decrease in demand can be attributed mainly to the changing structure of the Czech economy and to environmental constraints. The continued production of energy from indigenous brown coals is a major concern for the Czech Republic. The strong desire to continue to use this resource is amore » challenge. The Energy and Environmental Research Center undertook two major efforts recently. One effort involved an assessment of opportunities for commercialization of US coal technologies in the Czech Republic. This report is the result of that effort. The technology assessment focused on the utilization of Czech brown coals. These coals are high in ash and sulfur, and the information presented in this report focuses on the utilization of these brown coals in an economically and environmentally friendly manner. Sections 3--5 present options for utilizing the as-mined coal, while Sections 6 and 7 present options for upgrading and generating alternative uses for the lignite. Contents include Czech Republic national energy perspectives; powering; emissions control; advanced power generation systems; assessment of lignite-upgrading technologies; and alternative markets for lignite.« less
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Sorption of the monoterpenes α-pinene and limonene to carbonaceous geosorbents including biochar.
Hale, Sarah E; Endo, Satoshi; Arp, Hans Peter H; Zimmerman, Andrew R; Cornelissen, Gerard
2015-01-01
The sorption of two monoterpenes, α pinene and limonene to the carbonaceous geosorbents graphite, bituminous coal, lignite coke, biochar and Pahokee peat was quantified. Polyethylene (PE) passive samplers were calibrated for the first time for these compounds by determining the PE-water partitioning coefficients and used as a tool to determine sorption to the carbonaceous geosorbents. Log KPE-water values were 3.49±0.58 for α pinene and 4.08±0.27 for limonene. The sorption of limonene to all materials was stronger than that for α pinene (differences of 0.2-1.3 log units between distribution coefficients for the monoterpenes). Placing Kd values in increasing order for α pinene gave biochar≈Pahokee peat≈bituminous coal≈lignite coke
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Petaloti, Christina; Triantafyllou, Athanasios; Kouimtzis, Themistoklis; Samara, Constantini
2006-12-01
Total suspended particle (TSP) concentrations were determined in the Eordea basin (western Macedonia, Greece), an area with intensive lignite burning for power generation. The study was conducted over a one-year period (November 2000-November 2001) at 10 sites located at variable distances from the power plants. Ambient TSP samples were analyzed for 27 major, minor and trace elements. Annual means of TSP concentrations ranged between 47+/-33 microg m(-3) and 110+/-50 microg m(-3) at 9 out of the 10 sites. Only the site closest to the power stations and the lignite conveyor belts exhibited annual TSP levels (210+/-97 microg m(-3)) exceeding the European standard (150 microg m(-3), 80/779/EEC). Concentrations of TSP and almost all elemental components exhibited significant spatial variations; however, the elemental profiles of TSP were quite similar among all sites suggesting that they are affected by similar source types. At all sites, statistical analysis indicated insignificant (P<0.05) seasonal variation for TSP concentrations. Some elements (Cl, As, Pb, Br, Se, S, Cd) exhibited significantly higher concentrations at certain sites during the cold period suggesting more intense emissions from traffic, domestic heating and other combustion sources. On the contrary, concentrations significantly higher in the warm period were found at other sites mainly for crustal elements (Ti, Mn, K, P, Cr, etc.) suggesting stronger influence from soil resuspension and/or fly ash in the warm months. The most enriched elements against local soil or road dust were S, Cl, Cu, As, Se, Br, Cd and Pb, whereas negligible enrichment was found for Ti, Mn, Mg, Al, Si, P, Cr. At most sites, highest concentrations of TSP and elemental components were associated with low- to moderate-speed winds favoring accumulation of emissions from local sources. Influences from the power generation were likely at those sites located closest to the power plants and mining activities.
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Leaching behavior of rare earth elements in fort union lignite coals of North America
Laudal, Daniel A.; Benson, Steven A.; Addleman, Raymond Shane; ...
2018-03-30
Fort Union lignite coal samples were subjected to a series of aqueous leaching experiments to understand the extraction behavior of the rare earth elements (REE). This testing was aimed at understanding the modes of occurrence of the REE in the lignite coals, as well as to provide foundational data for development of rare earth extraction processes. In a first series of tests, a sequential leaching process was used to investigate modes of occurrence of the REE of select lignite coals. The tests involved sequential exposure to solvents consisting of water, ammonium acetate and dilute hydrochloric acid (HCl). The results indicatedmore » that water and ammonium acetate extracted very little of the REE, indicating the REE are not present as water soluble or ion-exchangeable forms. However, the data shows that a large percentage of the REE were extracted with the hydrochloric acid (80–95 wt%), suggesting presence in HCl-soluble mineral forms such as carbonates, and/or presence as organic complexes. A second series of tests was performed involving single-step leaching with dilute acids and various operating parameters, including acid type, acid concentration, acid/coal contact time and coal particle size. For select samples, additional tests were performed to understand the results of leaching, including float-sink density separations and humic acid extraction. The results have shown that the majority of REE in Fort Union lignites appear to be associated weakly with the organic matrix of the coals, most likely as coordination complexes of carboxylic acid groups. The light REE and heavy REE exhibit different behaviors, however. The extractable light REE appear to have association both in acid-soluble mineral forms and as organic complexes, whereas the extractable heavy REE appear to be almost solely associated with the organics. In conclusion, scandium behavior was notably different than yttrium and the lanthanides, and the data suggests the extractable content is primarily associated as acid-soluble mineral forms.« less
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Mid-latitude continental temperatures through the early Eocene in western Europe
NASA Astrophysics Data System (ADS)
Inglis, Gordon N.; Collinson, Margaret E.; Riegel, Walter; Wilde, Volker; Farnsworth, Alexander; Lunt, Daniel J.; Valdes, Paul; Robson, Brittany E.; Scott, Andrew C.; Lenz, Olaf K.; Naafs, B. David A.; Pancost, Richard D.
2017-02-01
Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are increasingly used to reconstruct mean annual air temperature (MAAT) during the early Paleogene. However, the application of this proxy in coal deposits is limited and brGDGTs have only been detected in immature coals (i.e. lignites). Using samples recovered from Schöningen, Germany (∼48°N palaeolatitude), we provide the first detailed study into the occurrence and distribution of brGDGTs through a sequence of early Eocene lignites and associated interbeds. BrGDGTs are abundant and present in every sample. In comparison to modern studies, changes in vegetation type do not appear to significantly impact brGDGT distributions; however, there are subtle differences between lignites - representing peat-forming environments - and siliciclastic nearshore marine interbed depositional environments. Using the most recent brGDGT temperature calibration (MATmr) developed for soils, we generate the first continental temperature record from central-western continental Europe through the early Eocene. Lignite-derived MAAT estimates range from 23 to 26 °C while those derived from the nearshore marine interbeds exceed 20 °C. These estimates are consistent with other mid-latitude environments and model simulations, indicating enhanced mid-latitude, early Eocene warmth. In the basal part of the section studied, warming is recorded in both the lignites (∼2 °C) and nearshore marine interbeds (∼2-3 °C). This culminates in a long-term temperature maximum, likely including the Early Eocene Climatic Optimum (EECO). Although this long-term warming trend is relatively well established in the marine realm, it has rarely been shown in terrestrial settings. Using a suite of model simulations we show that the magnitude of warming at Schöningen is broadly consistent with a doubling of CO2, in agreement with late Paleocene and early Eocene pCO2 estimates.
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Continental temperatures through the early Eocene in western central Europe
NASA Astrophysics Data System (ADS)
Inglis, G. N.; Collinson, M. E.; Riegel, W.; Wilde, V.; Farnsworth, A.; Lunt, D. J.; Robson, B.; Scott, A. C.; Lenz, O.; Pancost, R.
2016-12-01
In contrast to the marine realm, our understanding of terrestrial temperature change during greenhouse climates is poorly constrained. Recently, branched glycerol dialkyl glycerol tetraethers (brGDGTs) have been used to successfully reconstruct mean annual air temperature (MAAT) during the early Paleogene. However, despite the potential to provide new insights into terrestrial climate, the application of this proxy in lignite and coal deposits is still limited. Using samples recovered from Schöningen, Germany ( 48°N), we provide the first detailed study into the occurrence and distribution of brGDGTs through a sequence of Early Eocene lignites and associated marine interbeds. Branched GDGTs are abundant and present in every sample. In comparison to modern studies, changes in vegetation type do not appear to significantly impact brGDGT distributions; however, there are subtle differences in these distributions between lignites and siliciclastic nearshore marine interbed sediments. Using the most recent brGDGT temperature calibration, we generate the first continental temperature record from central-western continental Europe through the Early Eocene. Lignite-derived MAAT estimates range from 23 to 26°C and those derived from the nearshore marine interbeds always exceed 20°C. These estimates are consistent with other mid-latitude palaeoclimate proxy records which indicate enhanced early Eocene warmth. In the basal part of the section, warming is recorded in both the lignites ( 2°C) and nearshore marine interbeds ( 2-3°C). This culminates in a long-term temperature maximum, likely including the Early Eocene Climatic Optimum (EECO). Although this trend is relatively well established in marginal marine sediments within the SW Pacific, it has rarely been shown in other regions or terrestrial settings. Using a suite of new climate model simulations, our warming trend is consistent with a doubling of CO2 (from 560ppmv to 1120ppmv) which broadly agrees with proxy-derived CO2 estimates from the early Paleogene
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Leaching behavior of rare earth elements in fort union lignite coals of North America
DOE Office of Scientific and Technical Information (OSTI.GOV)
Laudal, Daniel A.; Benson, Steven A.; Addleman, Raymond Shane
Fort Union lignite coal samples were subjected to a series of aqueous leaching experiments to understand the extraction behavior of the rare earth elements (REE). This testing was aimed at understanding the modes of occurrence of the REE in the lignite coals, as well as to provide foundational data for development of rare earth extraction processes. In a first series of tests, a sequential leaching process was used to investigate modes of occurrence of the REE of select lignite coals. The tests involved sequential exposure to solvents consisting of water, ammonium acetate and dilute hydrochloric acid (HCl). The results indicatedmore » that water and ammonium acetate extracted very little of the REE, indicating the REE are not present as water soluble or ion-exchangeable forms. However, the data shows that a large percentage of the REE were extracted with the hydrochloric acid (80–95 wt%), suggesting presence in HCl-soluble mineral forms such as carbonates, and/or presence as organic complexes. A second series of tests was performed involving single-step leaching with dilute acids and various operating parameters, including acid type, acid concentration, acid/coal contact time and coal particle size. For select samples, additional tests were performed to understand the results of leaching, including float-sink density separations and humic acid extraction. The results have shown that the majority of REE in Fort Union lignites appear to be associated weakly with the organic matrix of the coals, most likely as coordination complexes of carboxylic acid groups. The light REE and heavy REE exhibit different behaviors, however. The extractable light REE appear to have association both in acid-soluble mineral forms and as organic complexes, whereas the extractable heavy REE appear to be almost solely associated with the organics. In conclusion, scandium behavior was notably different than yttrium and the lanthanides, and the data suggests the extractable content is primarily associated as acid-soluble mineral forms.« less
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Wyant, Donald G.; Beroni, Ernest P.
1950-01-01
The exact mode of origin of the uranium in the lignite is not known. Uranium may have accumulated in swamps at the same time as the organic debris, or it may have been introduced by ground water after the formation of lignite. In either case carbon or carbon compounds apparently caused the precipitation or fixation of uranium. Further work is needed to determine the origin of this type of uranium deposit.
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Kolak, J.J.; Burruss, R.C.
2006-01-01
Coal samples of different rank (lignite to anthracite) were extracted in the laboratory with supercritical CO2 (40 ??C; 10 MPa) to evaluate the potential for mobilizing non-methane hydrocarbons during CO2 storage (sequestration) or enhanced coal bed methane recovery from deep (???1-km depth) coal beds. The total measured alkane concentrations mobilized from the coal samples ranged from 3.0 to 64 g tonne-1 of dry coal. The highest alkane concentration was measured in the lignite sample extract; the lowest was measured in the anthracite sample extract. Substantial concentrations of polycyclic aromatic hydrocarbons (PAHs) were also mobilized from these samples: 3.1 - 91 g tonne-1 of dry coal. The greatest amounts of PAHs were mobilized from the high-volatile bituminous coal samples. The distributions of aliphatic and aromatic hydrocarbons mobilized from the coal samples also varied with rank. In general, these variations mimicked the chemical changes that occur with increasing degrees of coalification and thermal maturation. For example, the amount of PAHs mobilized from coal samples paralleled the general trend of bitumen formation with increasing coal rank. The coal samples yielded hydrocarbons during consecutive extractions with supercritical CO2, although the amount of hydrocarbons mobilized declined with each successive extraction. These results demonstrate that the potential for supercritical CO2 to mobilize non-methane hydrocarbons from coal beds, and the effect of coal rank on this process, are important to consider when evaluating deep coal beds for CO2 storage.
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Noli, Fotini; Tsamos, Panagiotis
2018-05-01
The radiological and chemical pollution of a cluster of four lakes in a lignite mining area of North-Western Greece was investigated using a variety of analytical techniques. Alpha spectrometry was applied to measure the activity concentrations of the uranium radioisotopes (U-234, U-235, and U-238) in waters. The mass activities of U-238, Th-232, and K-40 in sediments were measured by high-resolution gamma spectrometry. Furthermore, the determination of the minor and trace elements was carried out by instrumental neutron activation analysis (INAA) in both water and sediments samples, respectively. Pollution levels were also evaluated by calculating enrichment factors (EFs), contamination factors (CFs) and pollution load index (PLI). The data were discussed taking into account several parameters such as the distance from the pollution source, temperature, and location and showed that the environmental impact in this region could not be considered as negligible. The deviation of the isotopic ratio of U-234/U-238 from the equilibrium value indicated waters with intensive dissolution of uranium. The activity values in both waters and sediments found to be low in cool periods and increased in warm periods. Moreover, the concentrations of the elements U, Zn, and Fe were raised in water samples indicating possible pollution as well as the CFs and PLI denoted accumulation in the sediments and moderate to severe contamination for Zn and Cr in some cases.
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Origin of hexavalent chromium in groundwater: The example of Sarigkiol Basin, Northern Greece.
Kazakis, N; Kantiranis, N; Kalaitzidou, K; Kaprara, E; Mitrakas, M; Frei, R; Vargemezis, G; Tsourlos, P; Zouboulis, A; Filippidis, A
2017-09-01
Hexavalent chromium constitutes a serious deterioration factor for the groundwater quality of several regions around the world. High concentrations of this contaminant have been also reported in the groundwater of the Sarigkiol hydrological basin (near Kozani city, NW Greece). Specific interest was paid to this particular study area due to the co-existence here of two important factors both expected to contribute to Cr(VI) presence and groundwater pollution; namely the area's exposed ophiolitic rocks and its substantial fly ash deposits originating from the local lignite burning power plant. Accordingly, detailed geochemical, mineralogical, hydro-chemical, geophysical and hydrogeological studies were performed on the rocks, soils, sediments and water resources of this basin. Cr(VI) concentrations varied in the different aquifers, with the highest concentration (up to 120μgL -1 ) recorded in the groundwater of the unconfined porous aquifer situated near the temporary fly ash disposal site. Recharge of the porous aquifer is related mainly to precipitation infiltration and occasional surface run-off. Nevertheless, a hydraulic connection between the porous and neighboring karst aquifers could not be delineated. Therefore, the presence of Cr(VI) in the groundwater of this area is thought to originate from both the ophiolitic rock weathering products in the soils, and the local leaching of Cr(VI) from the diffused fly ash located in the area surrounding the lignite power plant. This conclusion was corroborated by factor analysis, and the strongly positively fractionated Cr isotopes (δ 53 Cr up to 0.83‰) recorded in groundwater, an ash leachate, and the bulk fly ash. An anthropogenic source of Cr(VI) that possibly influences groundwater quality is especially apparent in the eastern part of the Sarigkiol basin. Copyright © 2017 Elsevier B.V. All rights reserved.
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Management of Lignite Fly Ash for Improving Soil Fertility and Crop Productivity
NASA Astrophysics Data System (ADS)
Ram, Lal C.; Srivastava, Nishant K.; Jha, Sangeet K.; Sinha, Awadhesh K.; Masto, Reginald E.; Selvi, Vetrivel A.
2007-09-01
Lignite fly ash (LFA), being alkaline and endowed with excellent pozzolanic properties, a silt loam texture, and plant nutrients, has the potential to improve soil quality and productivity. Long-term field trials with groundnut, maize, and sun hemp were carried out to study the effect of LFA on growth and yield. Before crop I was sown, LFA was applied at various doses with and without press mud (an organic waste from the sugar industry, used as an amendment and source of nutrients). LFA with and without press mud was also applied before crops III and V were cultivated. Chemical fertilizer, along with gypsum, humic acid, and biofertilizer, was applied in all treatments, including the control. With one-time and repeat applications of LFA (with and without press mud), yield increased significantly (7.0-89.0%) in relation to the control crop. The press mud enhanced the yield (3.0-15.0%) with different LFA applications. The highest yield LFA dose was 200 t/ha for one-time and repeat applications, the maximum yield being with crop III (combination treatment). One-time and repeat application of LFA (alone and in combination with press mud) improved soil quality and the nutrient content of the produce. The highest dose of LFA (200 t/ha) with and without press mud showed the best residual effects (eco-friendly increases in the yield of succeeding crops). Some increase in trace- and heavy-metal contents and in the level of γ-emitters in soil and crop produce, but well within permissible limits, was observed. Thus, LFA can be used on a large scale to boost soil fertility and productivity with no adverse effects on the soil or crops, which may solve the problem of bulk disposal of fly ash in an eco-friendly manner.
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Jasion, Mateusz; Samecka-Cymerman, Aleksandra; Kolon, Krzysztof; Kempers, Alexander J
2013-10-01
We investigated the possibility of use of Tanacetum vulgare (tansy) as an ecological indicator of metal concentration in a naturally colonized open-pit lignite mine in Bełchatów (Poland). Tanacetum vulgare is the only species growing abundantly and spontaneously in the lignite mine waste dumps. Metal concentrations in roots, stems, leaves, flowers, and soil were measured in dump sites differing in type and time of reclamation and therefore differing in pollution levels. Tanacetum vulgare appeared to be an accumulator of chromium and iron in roots, whereas highest concentrations of manganese and zinc were found in leaves. A high bioaccumulation factor for cadmium (Cd) was observed in dumps and control sites, indicating that even small amounts of Cd in the environment may result in significant uptake by the plant. The lowest concentrations of metals were found in plants from sites situated on dumps reclaimed with argillaceous limestone.
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Altitude of the top of the Sparta Sand and Memphis Sand in three areas of Arkansas
Pugh, Aaron L.; Westerfield, Paul W.; Gonthier, Gerard; Poynter, David T.
1998-01-01
The Sparta Sand and Memphis Sand form the second most productive aquifer in Arkansas. The Sparta Sand and Memphis Sand range in thick- ness from 0 to 900 feet, consisting of fine- to medium-grained sands interbedded with layers of silt, clay, shale, and minor amounts of lignite. Within the three areas of interest, the top surface of the Sparta Sand and Memphis Sand dips regionally east and southeast towards the axis of the Mississippi Embayment syncline and Desha Basin. Local variations in the top surface may be attributed to a combination of continued development of structural features, differential compaction, localized faulting, and erosion of the surface prior to subsequent inundation and deposition of younger sediments.
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NASA Astrophysics Data System (ADS)
Sienkiewicz, Elwira; Gasiorowski, Michal
2015-04-01
In south-west Poland (central Europe) many the post-mining lakes formed so-called "the Anthropogenic Lake District". Areas, where water comes in contact with lignite beds characterized by high concentration of sulfide minerals are called Acid Mine Drainage (AMD). Pyrite oxidation and other sulfide compounds caused release sulfuric acids and heavy metal ions. These processes caused decline of water pH, sometimes to extremely low pH < 2.8. Presently, pit lakes located in south-west Poland have water pH ranged between 2.7 and 8.9. Differences of water reaction in the mine lakes depend on many factors, such as bedrock buffer capacity, geological structure of carboniferous area, exploitation technique of lignite, methods of filling and water supply of reservoirs and their age. During the evolution of lakes' ecosystems, sulfate-iron-calcium type of waters occurring in acid lakes will transform in alkaline hydrogen-carbonate-calcium type of waters. Due to the different time of the completion of lignite exploitation, lakes' age varied between forty and over one hundred years. Studies showed that younger lakes are more acidic in compare to older. To estimate impact of AMD we analyzed recent diversity of diatoms and Cladocera remains and water chemistry from extremely acidic, relatively young lakes and from alkaline, older water bodies. As we expected, flora and fauna from acidic lakes have shown very low diversity and species richness. Among diatoms, Eunotia exigua (Bréb. ex Kütz.) Rabenhorst and/or E. paludosa Grunow were dominated taxa, while fauna Cladocera did not occurred in lakes with water pH < 3. On this area, exploitation of lignite continued up to 1973. Older lakes were formed in the region where the mine started work in 1880 and lignite mining stopped in 1926. Measurements of pH value in situ point to neutral or alkaline water, but because of the possibility of hysteresis phenomenon, the studies of phyto- and zooplankton have shown if there has already been a widespread neutralization of lake ecosystems, what encompassing both recovery of water chemistry and rebuilding of biota communities. Studies have confirmed, that phyto- and zooplankton living nowadays in lakes located on this area, where exploitation of lignite ended at the beginning of 20th century, indicate completely recovery from acidification caused by coal mine activities. Presently, the lakes were dominated by planktonic diatoms and Cladocera taxa, such as Discostella pseudostelligera (Hust.) Houk & Klee and Bosmina longirostris, respectively.
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Approaches to Post-Mining Land Reclamation in Polish Open-Cast Lignite Mining
NASA Astrophysics Data System (ADS)
Kasztelewicz, Zbigniew
2014-06-01
The paper presents the situation regarding the reclamation of post-mining land in the case of particular lignite mines in Poland until 2012 against the background of the whole opencast mining. It discusses the process of land purchase for mining operations and its sales after reclamation. It presents the achievements of mines in the reclamation and regeneration of post-mining land as a result of which-after development processes carried out according to European standards-it now serves the inhabitants as a recreational area that increases the attractiveness of the regions.
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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.
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Dingman, Robert James; Gordon, Ellis D.; Swenson, H.A.
1954-01-01
The Fort Berthold Indian Reservation occupies about 1,000 square miles in west- central North Dakota. The Missouri and Little Missouri Rivers flow through the area and form part of its boundaries. Garrison Dam, which is under construction on the Missouri River 30 miles downstream from the east boundary of the reservation, will impound water in Garrison Reservoir and flood the valleys of both rivers throughout the area. The reservoir will divide the reservation into five parts, herein referred to as the eastern, northeastern, northern, western, and southern segments. Rock formations ranging in age from Paleocene to Recent are exposed. The Fort Union formation of Paleocene age underlies the entire reservation, and it crops out along the Missouri and Little Missouri Rivers. Relatively thin glacial till and outwash deposits of late Pleistocene age mantle much of the upland in all of the segments. The glacial de. posits commonly are less than 10 feet thick; in many places they consist only of scattered boulders on the bedrock surface. The major valleys have terrace deposits of Pleistocene and Recent age and alluvium of Recent age. The principal mineral resources of the reservation are lignite, sand, and gravel. The lignite beds range in thickness from a few inches to about 30 feet. At least four separate beds, which range in thickness from 4 feet to more than 7 feet, are mined locally. Although many mines will be flooded after Garrison Dam is completed, many suitable mine sites will remain above the proposed reservoir level. Sand and gravel deposits are found in glacial outwash and in stream-terrace deposits. On upland areas of the reservation ground water is available principally from the lignite and the associated fine- to medium-grained sandstone beds of the Fort Union formation. Few wells on the reservation are known to produce water from glacial material, although the recessional moraines are possible sources of shallow-water supplies. Small quantities of ground water are available from thin alluvial deposits in some places on the upland. Most wells in the valleys produce water from the alluvium or the terrace deposits. However, several wells penetrate the underlying Fort Union formation. A few flowing wells in the Missouri River valley near Elbowoods produce water from either the lower part of the Fort Union formation or from the Cannonball formation, also of Paleocene age. The chemical character of water from the Fort Union formation and the outwash and river gravels was determined from analyses of 39 samples from wells and springs. Water from bedrock may be either hard or soft, and it is moderately to highly mineralized. Water from the surficial deposits is uniformly hard, but it is less mineralized. Shallow wells in the eastern and northeastern segments produce water of good quality. Wells in these segments, and several springs in the western segment, could be used satisfactorily as domestic supplies. Spring water from lignite deposits on the reservation generally is colored and contains objectionable amounts of iron. Treatment of the water would improve its quality for domestic use. The filling of Garrison Reservoir will cause a rise of the water levels in wells that tap aquifers now discharging below the operating level of the reservoir. All the permeable strata below this level will become saturated, and ground-water bodies that are now separated will become hydraulically united. In addition to providing subsurface information, the drilling program of the U. S. Bureau of Indian Affairs provided wells for domestic and stock-water supplies. All test holes that tapped an adequate supply of potable water were reamed to a larger diameter, equipped with casing and well screen, and gravel-packed. The test-drilling program was completed in 1951; however, the drilling of domestic wells was continued under the supervision of the U. S. Geological Survey.
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Armstrong, C.A.
1985-01-01
The investigation was undertaken to define the geohydrology of the Sand Creek-Hanks area and to project probable hydrologic effects of lignite mining on the area. Aquifers occur in sandstone beds in the Fox Hills Sandstone and the Hell Creek Formation of Cretaceous age and in sandstone lenses and lignite beds in the Tongue River and Sentinel Butte Members of the Fort Union Formation of Tertiary age.The top of the Fox Hills aquifer ranges from about 1,200 to 2,000 feet below land surface. Yields of wells completed in the aquifer could be as much as 60 gallons per minute. Water in the Fox Hills aquifer is a sodium bicarbonate type and generallyDepths to the top of the Hell Creek aquifer range from about 900 to 1,600 feet. Well yields range from less than 10 to 40 gallons per minute. Water in the aquifer is a sodium bicarbonate type and generally contains between 1,000 and 2,200 milligrams per liter dissolved solids. Depths to aquifers in the Tongue River and Sentinel Butte Members of Fort Union Formation range from near land surface to about 1,000 feet below land surface. Wells completed in the aquifers may yield as much as 40 gallons per minute of sodium bicarbonate or a sodium sulfate type water that contains about 800 to 4,100 milligrams per liter dissolved solids.Glacial drift covers most of the study area. The drift thickness ranges from a veneer to about 380 feet. Well yields range from a few gallons per minute to 900 gallons per minute. Dissolved-solids concentrations in water from the glacial drift generally range from 477 to 2,050 milligrams per liter. Mining of lignite will destroy all aquifers in and above the mined lignite and will expose overburden to oxidation. Leaching will cause an increase in dissolved solids in ground water immediately beneath the mines and possibly will cause some increase in the dissolved solids in low flows in area streams.
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Design assessment of a 150 kWt CFBC Test Unit
DOE Office of Scientific and Technical Information (OSTI.GOV)
Batu, A.; Selcuk, N.; Kulah, G.
2010-04-15
For clean and efficient energy generation from coal, the most suitable technology known to date is 'Fluidized Bed Combustion' technology. Applications of circulating fluidized bed (CFB) combustion technology have been steadily increasing in both capacity and number over the past decade. Designs of these units have been based on the combustion tests carried out in pilot scale facilities to determine the combustion and desulfurization characteristics of coal and limestone reserves in CFB conditions. Similarly, utilization of Turkish lignites in CFB boilers necessitates adaptation of CFB combustion technology to these resources. However, the design of these test units are not basedmore » on firing coals with high ash, volatile matter and sulfur contents like Turkish lignites. For this purpose, a 150 kWt CFB combustor test unit is designed and constructed in Chemical Engineering Department of Middle East Technical University, based on the extensive experience acquired at the existing 0.3 MWt Bubbling Atmospheric Fluidized Bed Combustor (AFBC) Test Rig. Following the commissioning tests, a combustion test is carried out for investigation of combustion characteristics of Can lignite in CFB conditions and for assessment of the design of test unit. Comparison of the design outputs with experimental results reveals that most of the predictions and assumptions have acceptable agreement with the operating conditions. In conclusion, the performance of 150 kWt CFBC Test Unit is found to be satisfactory to be utilized for the long term research studies on combustion and desulfurization characteristics of indigenous lignite reserves in circulating fluidized bed combustors. (author)« less
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Research on a new type of additive for CWS from low temperature pyrolysis tar
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu Guoguang; Wang Zuna
1997-12-31
In this paper, coal tar from flash pyrolysis of Ping Zhuang lignite with solid heat carrier was used as raw material, which was directly synthesized a new type of additive for coal water slurry (CWS) in the laboratory. The wetting heat between the lignite and distilled water and solution of additive has been determined. It is evident that the wetting heat between the lignite and distilled water is very high, up to 44.56 J/g, which is harmful to preparing CWS. The wetting heat between the lignite and a solution of additive is reduced, which is related to its characteristics suchmore » as surface properties, oxygen functional groups and structure. The effect of coal properties on preparing CWS has also been analyzed systematically. It is suggested that the concentration of CWS is regularly changed with oxygen content of coal based on moisture and ash content. It is emphasized that when the influence of macerals on slurriability of coal is observed, inherent properties of each maceral such as pore structure, porosity, oxygen functional groups, grindability must be tightly combined to evaluate comprehensively. The structural characteristics of the additive matches well the molecular structure and surface properties of the coal. It is seen by synthetic experiments that suitable a degree of sulphonating and condensation are beneficial to preparing CWS. The rheology and stability of CWS have also been investigated. The result indicates that the stability of CWS using the new type of additive is improved, and the production cost of the additive synthesized from low temperature pyrolysis coal tar can be reduced.« less
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Shrestha, Sohan; Son, Guntae; Lee, Seung Hwan; Lee, Tae Gwan
2013-08-01
The Zn (II) adsorption capacity of lignite and coconut shell-based activated carbon fiber (ACF) was evaluated as a function of initial Zn (II) concentration, temperature and contact time in batch adsorption process in this study. Adsorption uptake increased with initial Zn (II) concentration and temperature. Optimal contact time for the adsorption of Zn (II) ions onto lignite and coconut shell-based ACF was found to be 50 min. Removal percentage decreased from 88.0% to 78.54% with the increment in initial Zn (II) concentration from 5 to 50 mg L(-1). Equilibrium data fit well with Langmuir-I isotherm indicating homogeneous monolayer coverage of Zn (II) ions on the adsorbent surface. Maximum monolayer adsorption capacity of Zn (II) ions on ACF was found to be 9.43 mg g(-1). Surface morphology and functionality of ACF prior to and after adsorption were characterized by electron microscopy and infrared spectroscopy. Various thermodynamic parameters such as standard Gibbs free energy (ΔG°), standard enthalpy (ΔH°), and standard entropy (ΔS°) were evaluated. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Skodras, G; Palladas, A; Kaldis, S P; Sakellaropoulos, G P
2007-04-01
In this paper, the co-combustion behaviour of coal with wastes and biomass and the related toxic gaseous emissions were investigated. The objective of this work is to add on towards a cleaner co-combustion of lignite-waste-biomass blends by utilizing compounds that could inhibit the formation of toxic pollutants. A series of co-combustion tests was performed in a pilot scale incinerator, and the emissions of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were measured. The co-combustion behaviour of lignite with olive kernels, MDF and sawdust was studied and the ability of additives such as urea, almond shells and municipal sewage sludge to reduce the PCDD/F emissions was examined. All blends were proven good fuels and reproducible combustion conditions were achieved. The addition of inhibitors prior to combustion showed in some cases, relatively high PCDD/F emissions reduction. Among the inhibitors tested, urea seems to achieve a reduction of PCDD/F emissions for all fuel blends, while an unstable behaviour was observed for the others.
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NASA Astrophysics Data System (ADS)
Woloszyn, Iwona; Merkel, Broder; Stanek, Klaus
2017-07-01
The management of natural resources has to follow the principles of sustainable development. Therefore, before starting new mining activities, it should be checked, whether existing deposits have been completely exploited. In this study, a three-dimensional (3D) cross-border geologic model was created to generalize the existing data of the Neogene Berzdorf-Radomierzyce basin, located in Upper Lusatia on the Polish-German border south of the city of Görlitz-Zgorzelec. The model based on boreholes and cross sections of abandoned and planned lignite fields was extended to the Bernstadt and Neisse-Ręczyn Graben, an important tectonic structure at the southern rim of the basin. The partly detailed stratigraphy of Neogene sequences was combined to five stratigraphic units, considering the lithological variations and the main tectonic structures. The model was used to check the ability of a further utilization of the Bernstadt and Neisse-Ręczyn Graben, containing lignite deposits. Moreover, it will serve as a basis for the construction of a 3D cross-border groundwater model, to investigate the groundwater flow and transport in the Miocene and Quaternary aquifer systems. The large amount of data and compatibility with other software favored the application of the 3D geo-modeling software Paradigm GOCAD. The results demonstrate a very good fit between model and real geological boundaries. This is particularly evident by matching the modeled surfaces to the implemented geological cross sections. The created model can be used for planning of full-scale mining operations in the eastern part of the basin (Radomierzyce).
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Ward, B.
We continued our tests for biosolubilization activity on lignite, subbituminous, and bituminous coals, using both surface solubilization and agar diffusion assays for selected lignite-solubilizing strains challenged with untreated and treated coals shown in earlier tests to be resistant to biosolubilization. These latter were subjected to treatments with heat or pressurized oxygen atmosphere, or to combinations of the same. We have observed biosolubilization of some weathered high-rank coals by some of the fungal isolates tested. 1 tab.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Russell, J.A.; Patel, B.B.
1987-11-03
A drilling fluid additive mixture is described consisting essentially of a sulfoalkylated tannin in admixture with a non-sulfoalkylated alkali-solubilized lignite wherein the weight ratio of the sulfoalkylated tannin to the non-sulfoalkylated lignite is in the range from about 2:1 to about 1:1. The sulfoalkylated tannin has been sulfoalkylated with at least one -(C(R-)/sub 2/-SO/sub 3/M side chain, wherein each R is selected from the group consisting of hydrogen and alkyl radicals containing from 1 to about 5 carbon atoms, and M is selected from the group consisting of ammonium and the alkali metals.
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Localized sulfate-reducing zones in a coastal plain aquifer
Brown, C.J.; Coates, J.D.; Schoonen, M.A.A.
1999-01-01
High concentrations of dissolved iron in ground water of coastal plain or alluvial aquifers contribute to the biofouling of public supply wells for which treatment and remediation is costly. Many of these aquifers, however, contain zones in which microbial sulfate reduction and the associated precipitation of iron-sulfide minerals decreases iron mobility. The principal water-bearing aquifer (Magothy Aquifer of Cretaceous age) in Suffolk County, New York, contains localized sulfate-reducing zones in and near lignite deposits, which generally are associated with clay lenses. Microbial analyses of core samples amended with [14C]-acetate indicate that microbial sulfate reduction is the predominant terminal-electron-accepting process (TEAP) in poorly permeable, lignite-rich sediments at shallow depths and near the ground water divide. The sulfate-reducing zones are characterized by abundant lignite and iron-sulfide minerals, low concentrations of Fe(III) oxyhydroxides, and by proximity to clay lenses that contain pore water with relatively high concentrations of sulfate and dissolved organic carbon. The low permeability of these zones and, hence, the long residence time of ground water within them, permit the preservation and (or) allow the formation of iron-sulfide minerals, including pyrite and marcasite. Both sulfate-reducing bacteria (SRB) and iron-reducing bacteria (IRB) are present beneath and beyond the shallow sulfate-reducing zones. A unique Fe(III)-reducing organism, MD-612, was found in core sediments from a depth of 187 m near the southern shore of Long Island. The distribution of poorly permeable, lignite-rich, sulfate-reducing zones with decreased iron concentration is varied within the principal aquifer and accounts for the observed distribution of dissolved sulfate, iron, and iron sulfides in the aquifer. Locating such zones for the placement of production wells would be difficult, however, because these zones are of limited aerial extent.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Cronauer, D.C.; Swanson, A.J.; Sajkowski, D.J.
Research under way in this project centers upon developing and evaluating catalysts and process improvements for coal liquefaction in the two-stage close-coupled catalytic process. Further experimentation was undertaken in a continuous flow unit with Black Thunder coal, where the primary goal was to determine the extent of decarboxylation and changes in the structure of the unconverted coal samples. The preliminary results indicated little conversion of the feed coal to THF solubles at 600{degrees}F, although the conversion did increase with increasing temperature up to 24% at 700{degrees}F. The level of decarboxylation was also low at the above reaction temperatures. Thus, presoakingmore » in a coal-derived solvent or even tetralin does not seem to be an effective means to achieve decarboxylation. Feedstock liquefaction studies were done with Martin Lake lignite in a two-stage continuous flow unit. Conversion to THF solubles was 82-87%. The Martin Lake lignite product was very light and no resid was produced. Sulfur levels in the product were low, although nitrogen levels were relatively high, requiring further processing by hydrotreating. An air-oxidized sample of Martin Lake lignite produced high oxygen containing resid at the expense of distillate, which clearly indicates that air oxidation of lignite is detrimental. The spent catalyst from the first stage was severely deactivated and generally, the spent catalysts from both stages were in worse condition than those from a previous run with Black Thunder coal. The completed testing results of Sandia`s NiMo/hydrous titanate oxide (NiMo/HTO) preparations are reported.« less
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Samara, Constantini; Argyropoulos, George; Grigoratos, Theodoros; Kouras, Αthanasios; Manoli, Εvangelia; Andreadou, Symela; Pavloudakis, Fragkiskos; Sahanidis, Chariton
2018-05-01
The Western Macedonian Lignite Center (WMLC) in northwestern Greece is the major lignite center in the Balkans feeding four major power plants of total power exceeding 4 GW. Concentrations of PM 10 (i.e., particulate matters with diameters ≤10 μm) are the main concern in the region, and the high levels observed are often attributed to the activities related to power generation. In this study, the contribution of fugitive dust emissions from the opencast lignite mines to the ambient levels of PM 10 in the surroundings was estimated by performing chemical mass balance (CMB) receptor modeling. For this purpose, PM 10 samples were concurrently collected at four receptor sites located in the periphery of the mine area during the cold and the warm periods of the year (November-December 2011 and August-September 2012), and analyzed for a total of 26 macro- and trace elements and ionic species (sulfate, nitrate, chloride). The robotic chemical mass balance (RCMB) model was employed for source identification/apportionment of PM 10 at each receptor site using as inputs the ambient concentrations and the chemical profiles of various sources including the major mine operations, the fly ash escaping the electrostatic filters of the power plants, and other primary and secondary sources. Mean measured PM 10 concentrations at the different sites ranged from 38 to 72 μg m -3 . The estimated total contribution of mines ranged between 9 and 22% in the cold period increasing to 36-42% in the dry warm period. Other significant sources were vehicular traffic, biomass burning, and secondary sulfate and nitrate aerosol. These results imply that more efficient measures to prevent and suppress fugitive dust emissions from the mines are needed.
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Condition-Based Conveyor Belt Replacement Strategy in Lignite Mines with Random Belt Deterioration
NASA Astrophysics Data System (ADS)
Blazej, Ryszard; Jurdziak, Leszek
2017-12-01
In Polish lignite surface mines, condition-based belt replacement strategies are applied in order to assure profitable refurbishment of worn out belts performed by external firms specializing in belt maintenance. In two of three lignite mines, staff asses belt condition subjectively during visual inspections. Only one mine applies specialized diagnostic device (HRDS) allowing objective magnetic evaluation of belt core condition in order to choose the most profitable moment for the dismantling of worn out belt segments from conveyors and sending them to the maintenance firm which provides their refurbishment. This article describes the advantages of a new diagnostic device called DiagBelt. It was developed at the Faculty of Geoengineering, Mining and Geology, Wroclaw University of Science and Technology. Economic gains from its application are calculated for the lignite mine and for the belt maintenance firm, taking into account random life (durability) of new and reconditioned belts (after the 1st and the 2nd refurbishment). Recursive calculations for following years allow the estimation of the length and costs of replaced, reconditioned and purchased belts on an annual basis, while the use of the Monte Carlo method allows the estimation of their variability caused by random deterioration of belts. Savings are obtained due to better selection of moments (times) for the replacement of belt segments and die to the possibility to qualify worn out belts for refurbishment without the need to remove their covers. In effect, increased belt durability and lowered share of waste belts (which were not qualified for reconditioning) create savings which can quickly cover expenditures on new diagnostic tools and regular belt inspections in the mine.
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Rostvall, Ande; Zhang, Wen; Dürig, Wiebke; Renman, Gunno; Wiberg, Karin; Ahrens, Lutz; Gago-Ferrero, Pablo
2018-06-15
This study evaluated the performance of five different sorbents (granular activated carbon (GAC), GAC + Polonite ® (GAC + P), Xylit, lignite and sand) for a set of 83 micropollutants (MPs) (pharmaceuticals, perfluoroalkyl substances (PFASs), personal care products, artificial sweeteners, parabens, pesticide, stimulants), together representing a wide range of physicochemical properties. Treatment with GAC and GAC + P provided the highest removal efficiencies, with average values above 97%. Removal rates were generally lower for Xylit (on average 74%) and lignite (on average 68%), although they proved to be highly efficient for a few individual MPs. The average removal efficiency for sand was only 47%. It was observed that the MPs behaved differently depending on their physicochemical properties. The physicochemical properties of PFASs (i.e. molecular weight, topological molecular surface area, log octanol water partition coefficient (K ow ) and distribution coefficient between octanol and water (log D)) were positively correlated to observed removal efficiency for the sorbents Xylit, lignite and sand (p < 0.05), indicating a strong influence of perfluorocarbon chain length and associated hydrophobic characteristics. In contrast, for the other MPs the ratio between apolar and polar surface area (SA/SP) was positively correlated with the removal efficiency, indicating that hydrophobic adsorption may be a key feature of their sorption mechanisms. GAC showed to be the most promising filter medium to improve the removal of MPs in on-site sewage treatment facilities. However, more studies are needed to evaluate the removal of MPs in field trials. Copyright © 2018 Elsevier Ltd. All rights reserved.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Sozen, A.; Arcaklioglu, E.
The main goal of this study is to develop the energy sources estimation equations in order to estimate the future projections and make correct investments in Turkey using artificial neural network (ANN) approach. It is also expected that this study will be helpful in demonstrating energy situation of Turkey in amount of EU countries. Basic energy indicators such as population, gross generation, installed capacity, net energy consumption, import, export are used in input layer of ANN. Basic energy sources such as coal, lignite, fuel-oil, natural gas and hydro are in output layer. Data from 1975 to 2003 are used tomore » train. Three years (1981, 1994 and 2003) are only used as test data to confirm this method. Also, in this study, the best approach was investigated for each energy sources by using different learning algorithms (scaled conjugate gradient (SCG) and Levenberg-Marquardt (LM)) and a logistic sigmoid transfer function in the ANN with developed software. The statistical coefficients of multiple determinations (R{sup 2}-value) for training data are equal to 0.99802, 0.99918, 0.997134, 0.998831 and 0.995681 for natural gas, lignite, coal, hydraulic, and fuel-oil, respectively. Similarly, these values for testing data are equal to 0.995623, 0.999456, 0.998545, 0.999236, and 0.99002. The best approach was found for lignite by SCG algorithm with seven neurons so mean absolute percentage error (MAPE) is equal to 1.646753 for lignite. According to the results, the future projections of energy indicators using ANN technique have been obviously predicted within acceptable errors. Apart from reducing the whole time required, the importance of the ANN approach is possible to find solutions that make energy applications more viable and thus more attractive to potential users.« less
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Extraction of organic materials from red water by metal-impregnated lignite activated carbon.
Wei, Fangfang; Zhang, Yihe; Lv, Fengzhu; Chu, Paul K; Ye, Zhengfang
2011-12-15
Extraction of organic materials from 2,4,6-trinitrotoluene (TNT) red water by lignite activated carbon (LAC) impregnated with Cu(2+), Ba(2+), Sn(2+), Fe(3+), Ca(2+) and Ag(+) was investigated. The affinity to organic materials in red water was found to follow the order: Cu/LAC>Sn/LAC>Ag/LAC>Ba/LAC>Fe/LAC>Ca/LAC, which was explained by the hard and soft acid base (HSAB) theory. Cu(2+) showed the best performance and several parameters were further studied. X-ray photoelectron spectroscopy (XPS) verified effective loading of Cu(2+) on the LAC surface. The water quality before and after treated by Cu/LAC was evaluated using high performance liquid chromatograph, Gas Chromatography/Mass Spectroscopy (GC/MS), UV-vis spectroscopy and other analyses. The extraction performances and mechanism of organic materials on Cu/LAC were investigated through static methods. The experimental results showed that Cu/LAC possessed stronger extraction ability for the sulfonated nitrotoluenes than the non-sulfonated nitrotoluenes, the kinetic data fitted the pseudo-second-order kinetic model well. In addition, the leaching out of Cu(2+) from Cu/LAC was found much lower in the 100 times diluted red water (0.074%) than in the raw water (10.201%). Column adsorptions with more concentrated red water were also studied. Finally, Cu/LAC was observed to possess excellent reusability as well. Copyright © 2011 Elsevier B.V. All rights reserved.
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Characterization of coals for circulating fluidized bed combustion by pilot scale tests
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lopez, L.A.; Cabanillas, A.C.; Becerra, J.O. de
1995-12-31
The major part of the Spanish coal supply is low range coal with both high ash (20--40%) and sulfur (1--8%) content. The use of this coal, by conventional combustion processes in power and industrial plants, implies a very high environmental impact. The Circulating Fluidized Bed Combustion process enables an efficient use of this coal. The Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas is carrying out a program with the intention of assisting companies in evaluating fuel quality impact, using atmospheric fluidized bed combustion. This paper reviews the major results of the fuel program in order to determine the fluidized bedmore » combustion performance of four fuels. Two lignites, a bituminous coal and an anthracite. The two lignites have very high sulfur content (7% and 8%) but the sulfur is organic in one case and pyritic in the other. The bituminous coal and the anthracite have 1% and 2% sulfur content respectively and the sulfur is pyritic in these cases. In order to reduce the sulfur in the flue gases, a high calcium content limestone has been used as sorbent. The combustion trials have been done in a circulating fluidized bed pilot plant with a 200 mm inside diameter and a height of 6.5 m. The influence of temperature, fluidization velocity, oxygen excess, Ca/S ratio and coal properties have been studied in relation to the combustion efficiency, sulfur retention, CO and NO{sub x} emissions.« less
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Liu, Jie; Jiang, Xiangang; Cao, Yu; Zhang, Chen; Zhao, Guangyao; Zhao, Maoshuang; Feng, Li
2018-05-07
Graphene oxide with different degrees of oxidation was prepared and selected as a model compound of lignite to study quantitatively, using both experiment and theoretical calculation methods, the effect on water-holding capacity of oxygen-containing functional groups. The experimental results showed that graphite can be oxidized, and forms epoxy groups most easily, followed by hydroxyl and carboxyl groups. The prepared graphene oxide forms a membrane-state as a single layer structure, with an irregular surface. The water-holding capacity of lignite increased with the content of oxygen-containing functional groups. The influence on the configuration of water molecule clusters and binding energy of water molecules of different oxygen-containing functional groups was calculated by density functional theory. The calculation results indicated that the configuration of water molecule clusters was totally changed by oxygen-containing functional groups. The order of binding energy produced by oxygen-containing functional groups and water molecules was as follows: carboxyl > edge phenol hydroxyl >epoxy group. Finally, it can be concluded that the potential to form more hydrogen bonds is the key factor influencing the interaction energy between model compounds and water molecules.
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NASA Astrophysics Data System (ADS)
Samara, Constantini
Total suspended particle mass concentrations (TSP) were determined in the Kozani-Ptolemais-Florina basin (western Macedonia, Greece), an area with intensive lignite burning for power generation. The study was conducted over a 1-year period (November 2000-November 2001) at 10 receptor sites located at variable distances from the power plants. Ambient TSP samples were analyzed for 27 major, minor and trace elements. Particulate emissions were also collected from a variety of sources including fly ash, lignite dust, automobile traffic, domestic heating, and open-air burning of agricultural biomass and refuse, and analyzed for the same chemical components. Ambient and source chemical profiles were used for source identification and apportionment of TSP by employing a chemical mass balance (CMB) receptor model. Diesel burning in vehicular traffic and in the power plants for generator start up was found to be the major contributor to ambient TSP levels at all 10 sites. Other sources with significant contributions were domestic coal burning, vegetative burning (wood combustion and agricultural burns) and refuse open-air burning. Fly ash escaping the electrostatic precipitators of the power plants was a minor contributor to ambient TSP.
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Land movement monitoring at the Mavropigi lignite mine using spaceborne D-InSAR
NASA Astrophysics Data System (ADS)
Papadaki, Eirini; Tripolitsiotis, Achilleas; Steiakakis, Chrysanthos; Agioutantis, Zacharias; Mertikas, Stelios; Partsinevelos, Panagiotis; Schilizzi, Pavlos
2013-08-01
This paper examines the capability of remote sensing radar interferometry to monitor land movements, as it varies with time, in areas close to open pit lignite mines. The study area is the "Mavropigi" lignite mine in Ptolemais, Northern Greece; whose continuous operation is of vital importance to the electric power supply of Greece. The mine is presently 100-120m deep while horizontal and vertical movements have been measured in the vicinity of the pit. Within the mine, ground geodetic monitoring has revealed an average rate of movement amounting to 10-20mm/day at the southeast slopes. In this work, differential interferometry (DInSAR), using 19 Synthetic Aperture Radar (SAR) images of ALOS satellite, has been applied to monitor progression of land movement caused my mining within the greater area of "Mavropigi" region. The results of this work show that DInSAR can be used effectively to capture ground movement information, well before signs of movements can be observed visually in the form of imminent fissures and tension cracks. The advantage of remote sensing interferometry is that it can be applied even in inaccessible areas where monitoring with ground equipment is either impossible or of high-cost (large areas).
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Moore, T.A.; Hilbert, R.E.
1992-01-01
Samples from two peat-forming environments of Holocene and Miocene age in Kalimantan (Borneo), Indonesia, were studied petrographically using nearly identical sample preparation and microscopic methodologies. Both deposits consist of two basic types of organic material: plant organs/tissues and fine-grained matrix. There are seven predominant types of plant organs and tissues: roots possessing only primary growth, stems possessing only primary growth, leaves, stems/roots with secondary growth, secondary xylem fragments, fragments of cork cells, and macerated tissue of undetermined origin. The fine-grained matrix consists of fragments of cell walls and cell fillings, fungal remains, spores and pollen grains, and resin. Some of the matrix material does not have distinct grain boundaries (at ??500) and this material is designated amorphous matrix. The major difference between the Holocene peat and Miocene lignite in reflected light, oil immersion is a loss of red coloration in the cell walls of tissue in the lignite, presumably due to loss of cellulosic compounds. In addition, cortex and phloem tissue (hence primary roots and stems) are difficult to recognize in the lignite, probably because these large, thin-walled tissues are more susceptible to microbial degradation and compaction. Particle size in both peat and lignite samples display a bimodal distribution when measurements are transformed to a - log2 or phi (??), scale. Most plant parts have modes of 2-3?? (0.25 - 0.125 mm), whereas the finer-grained particulate matrix has modes of 7-9?? (0.008-0.002 mm). This similarity suggest certain degradative processes. The 2-3?? range may be a "stable" size for plant parts (regardless of origin) because this is a characteristics of a substrate which is most suitable for plant growth in peat. The finer-grained matrix material (7-9??) probably results from fungal decay which causes plant material to weaken and with slight physical pressure to shatter into its component parts, i.e. fragments of cell walls and fillings. The absence of differences in particle size between the peat and lignite also indicate little compaction of organic components; rather an extreme loss in water content and pore space has occurred from between the particles of organic material. ?? 1992.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Greig, Chris; Larson, Eric; Kreutz, Thomas
We report on a 30-month design study for a first-of-a-kind (FOAK) demonstration plant that would be built at a site near Meridian, Mississippi, to coprocess lignite coal and woody biomass into jet fuel. The design uses an oxygen-blown TRIG™ gasifier developed by KBR and Southern Company. Fischer-Tropsch conversion of the syngas produces synthetic paraffinic kerosene (SPK) as the primary product, plus naphtha. Other co-products include electricity sold to the grid and CO2 sold for use in enhanced oil recovery (EOR). Previous studies have identified coprocessing of various coals and biomass with CO2 capture as promising options for cost-competitive production ofmore » low net lifecycle greenhouse gas (GHG) emissions synthetic fuels. The effort reported here goes beyond earlier studies in the level of detail in process design and cost estimation with the aim of improving the understanding of the economic prospects for lignite and woody biomass coprocessing systems. Key objectives in the design of the FOAK lignite/biomass-to-jet (LBJ) plant were to achieve net lifecycle GHG emissions for the SPK that are less than for conventional petroleum-derived jet fuel and to make process design and equipment selections such that the plant could be built and operated in the near term, e.g., before 2025. The process design was developed by researchers at Princeton University and the University of Queensland and validated by engineers at the WorleyParsons Group (WP). Commercial vendors provided design and cost estimates for several major plant components. Bare-erected capital costs and operating and maintenance costs were estimated by WP. The primary objective in building and operating the FOAK plant would be to demonstrate the technical viability of the LBJ concept as an essential first step toward launching commercial-scale plants in the longer term. With this in mind, the project team developed a set of principles to help guide the process design: the total plant cost should be less than $2 billion (to limit investment risk); the level of input biomass should be both proportionally significant to reflect biomass/lignite co-gasification and sufficient to achieve GHG emissions goals; process design decisions and vendor/equipment selections should prioritize the likelihood of technical success over minimizing the cost of jet fuel production. The resulting FOAK plant design capacity is 1,551 metric t/d (45.5% moisture) lignite and 556 t/d (43.3% moisture) biomass, for a total input of 295 MWHHV, of which 25% is biomass. The design output is 1,252 actual barrels per day of liquids, of which 80% is SPK (62.3 MWLHV) and 20% is naphtha (13.9 MWLHV). It exports 15 MWe of electricity after satisfying a 38 MWe onsite auxiliary load. Additional products are 1,326 t/d of pressurized pipeline-quality CO2 and 49 t/day of sulfuric acid (93 wt% H2SO4). With thinnings from sustainably-managed southern pine plantations as the biomass, and with captured CO2 stored underground via EOR, the net lifecycle emissions for the SPK product are estimated to be about one-quarter of those for petroleum-derived jet fuel. The bare-erected cost (BEC) estimated by WP for this plant is $588 million (2015$). The authors’ best estimate of total plant cost (TPC) is $1,230 million, arrived at by assuming engineering, procurement and construction management services (20% of BEC), process 5 contingencies (35% of BEC), and project contingencies (35% of the sum of all other costs, i.e., 35% of 1.55xBEC). Not surprisingly, an annual discounted cash flow (DCF) analysis determined that it would be impossible to generate a positive net present value (NPV) over a wide range in key input assumptions. An SPK production cost subsidy of nearly $400/bbl over a 20-year plant life would be required to achieve zero NPV under a baseline set of assumptions (including 3% real weighted average cost of capital and a levelized crude oil price of $80/bbl). Alternatively, a capital grant in excess of the TPC value would also achieve zero NPV. The poor financial results reflect the small scale of the plant, the design principle to prioritize technical success, the levels of contingencies appropriate for the relatively early stage of project development, and the first-of-a-kind nature of the plant. Technology innovations, learning via construction and operating experience, alternative plant configurations, and larger scale should improve economics of future plants. To help understand these prospects, a preliminary analysis of Nth-of-a-kind (NOAK) plants was developed, but with the limitation that plants would use only equipment components that for the most part are already commercial today: consideration of advanced, not-yet-commercial technologies and of R&D-driven improvements in existing technologies were beyond the scope of this analysis. The analysis found that a variety of NOAK plant designs that coprocess lignite and woody biomass to make jet fuel are unlikely to be economically competitive without subsidy even in the presence of a high future carbon tax or equivalent greenhouse gas mitigation policy. This conclusion applies to process configurations and input biomass/lignite ratios that result in net GHG emissions as high as those for petroleum-derived jet fuel and as low as zero. In contrast, encouraging results were found for plants processing only biomass. The economics of these “BECCS” plants (biomass energy with CCS) improve dramatically with the strength of carbon mitigation policies because of their strongly negative net GHG emissions. These findings do not imply that coal/biomass coprocessing strategies for making synfuels with CCS are not economically promising – only that, in the case of lignite, much more than a 25% biomass coprocessing rate would be needed. However, our analysis shows that all such systems are unlikely to be economic in the absence of a strong carbon mitigation policy. Future R&D driven technological innovations could modify this conclusion. Among other R&D priorities, an emphasis on better understanding and reducing plant auxiliary loads is warranted.« less
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Mastalerz, Maria; Schimmelmann, A.
2002-01-01
Hydrogen isotopic exchangeability (Hex) and ??Dn values of non-exchangeable organic hydrogen were investigated in coal kerogens ranging in rank from lignite to graphite. The relative abundance of Hex is highest in lignite with about 18% of total hydrogen being exchangeable, and decreases to around 2.5% in coals with Ro of 1.7 to ca. 5.7%. At Still higher rank (Ro > 6%), Hex increases slightly, although the abundance of total hydrogen decreases. ??Dn is influenced by original biochemical D/H ratios and by thermal maturation in contact with water. Therefore, ??Dn does not show an overall consistent trend with maturity. ?? 2002 Elsevier Science Ltd. All rights reserved.
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Trends in coal use - global, EU and Poland
NASA Astrophysics Data System (ADS)
Suwała, Wojciech; Wyrwa, Artur; Olkuski, Tadeusz
2017-11-01
That aim of this paper is to compare trends in global, European use of coal with tendencies in Poland, one of heavy coal dependent countries. Polish power generation is unique among OECD countries, the share of both hard coal and lignite in power generation reaches 81% [1]. Climate policy of European Union is to phase out intensive greenhouse gases sectors, thus to transform Polish power generation into less carbon intensive. Although such policy is generally accepted in Poland, the paste and practically proposed regulation that excludes coal generation from capacity mechanisms, is considered as threat to energy security. Coal is the base for generation for one simple reason, abundant in European scale hard coal reserves and significant capacities in lignite. Natural gas reserves allow to supply about 1/3 of consumption, but prices and supplies dependent hitherto on contracts with GAZPROM did not allow to develop significant generation capacities. Renewable resources are limited, there is not much possibilities for hydro, wind and solar. Poland is also one of the countries of poor air quality, traditional coal based space heating systems plus obsolete car fleet generate vast emissions, especially during the winter. Only recently this became top priority of environmental authorities. This situation is subject to transformation, government, managers are aware that the role of coal needs to be decreased, but there are two main questions, the paste of transformation and the future energy mix. The paper attempts to answer the question whether the expected changes in Polish energy mix are comparable or differ from the global and European tendencies.
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Structural degradation of Thar lignite using MW1 fungal isolate: optimization studies
Haider, Rizwan; Ghauri, Muhammad A.; Jones, Elizabeth J.; Orem, William H.; SanFilipo, John R.
2015-01-01
Biological degradation of low-rank coals, particularly degradation mediated by fungi, can play an important role in helping us to utilize neglected lignite resources for both fuel and non-fuel applications. Fungal degradation of low-rank coals has already been investigated for the extraction of soil-conditioning agents and the substrates, which could be subjected to subsequent processing for the generation of alternative fuel options, like methane. However, to achieve an efficient degradation process, the fungal isolates must originate from an appropriate coal environment and the degradation process must be optimized. With this in mind, a representative sample from the Thar coalfield (the largest lignite resource of Pakistan) was treated with a fungal strain, MW1, which was previously isolated from a drilled core coal sample. The treatment caused the liberation of organic fractions from the structural matrix of coal. Fungal degradation was optimized, and it showed significant release of organics, with 0.1% glucose concentration and 1% coal loading ratio after an incubation time of 7 days. Analytical investigations revealed the release of complex organic moieties, pertaining to polyaromatic hydrocarbons, and it also helped in predicting structural units present within structure of coal. Such isolates, with enhanced degradation capabilities, can definitely help in exploiting the chemical-feedstock-status of coal.
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Rehabilitation of a lignite mine-disturbed area in the Indian Desert
Sharma, K.D.; Kumar, P.; Gough, L.P.; SanFilipo, J.R.
2004-01-01
Extensive lignite mining in the Indian (Thar) Desert commenced within the past decade. Accompanying extraction of this valuable resource there have been visible, important environmental impacts. The resultant land degradation has prompted concern from both public and regulatory bodies. This research assesses the success of rehabilitation plans implemented to revegetate a lignite mine-disturbed area, near the village of Giral in western Rajasthan State. Rehabilitation success was achieved within the environmental constraints of this northwest Indian hot-desert ecosystem using a combination of: (1) backfilling (abandoned pits) with minespoil and of covering the backfilled-surfaces with fresh topsoil to a thickness of about 0??30 m; (2) use of micro-catchment rainwater harvesting (MCWH) technique; (3) soil profile modification approaches; (4) plant establishment methodologies; and (5) the selection of appropriate germplasm material (trees, shrubs and grasses). Preliminary results indicate that the resulting vegetative cover will be capable of self-perpetuation under natural conditions while at the same time meeting the land-use requirements of the local people. The minespoil is alkaline in nature and has high electrical conductance. The average content of organic carbon, N, P and K is lower than in the regional topsoil. However, the concentration of Ca, Mg, Na and total S in the minespoil is much higher than in the topsoil. Further, the spoil material has no biological activity. Enhanced plant growth was achieved in MCWH plots, compared to control plots, where minespoil moisture storage was improved by 18-43 per cent. The rehabilitation protocol used at the site appears to have been successful because, in addition to the planted species, desirable native invasive species have become established. This study developed methods for the rehabilitation of lignite mine-disturbed areas and has also resulted in an understanding of rehabilitation processes in arid regions with an emphasis on the long-term monitoring of rehabilitation success. ?? 2004 John Wiley and Sons, Ltd.
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NASA Astrophysics Data System (ADS)
Giri Babu, P. V. S.; Swaminathan, G.
2016-09-01
A comprehensive study was carried out on four different fly ashes used as a catalyst for the degradation of Acid Red 1 using ultraviolet rays. These fly ashes are collected from different thermal power stations located at various places in India and having different chemical compositions. Three fly ashes are from lignite-based thermal power plants, and one is from the coal-based power plant. One fly ash is classified as Class F, two fly ashes are classified as Class C and remaining one is not conforming to ASTM C618 classification. X-Ray Fluorescence analysis was used to identify the chemical composition of fly ashes and SiO2, Al2O3, CaO, Fe2O3 and TiO2 were found to be the major elements present in different proportions. Various analysis were carried out on all the fly ashes like Scanning Electron Microscopy to identify the microphysical properties, Energy Dispersive X-Ray spectroscopy to quantify the elements present in the catalyst and X-Ray Diffraction to identify the catalyst phase analysis. The radical generated during the reaction was identified by Electron paramagnetic resonance spectroscopy. The parameters such as initial pH of the dye solution, catalyst dosage and initial dye concentration which influence the dye degradation efficiency were studied and optimised. In 60 min duration, the dye degradation efficiency at optimum parametric values of pH 2.5, initial dye concentration of 10 mg/L and catalyst dosage of 1.0 g/L using various fly ashes, i.e., Salam Power Plant, Barmer Lignite Power Plant, Kutch Lignite Power Plant and Neyveli Lignite Thermal Power plant (NLTP) were found to be 40, 60, 67 and 95 % respectively. The contribution of adsorption alone was 18 % at the above mentioned optimum parametric values. Among the above four fly ash NLTP fly ashes proved to be most efficient.
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Zawadzki, Jarosław; Przeździecki, Karol; Miatkowski, Zygmunt
2016-01-15
Problems with lowering of water table are common all over the world. Intensive pumping of water from aquifers for consumption, irrigation, industrial or mining purposes often causes groundwater depletion and results in the formation of cone of depression. This can severely decrease water pressure, even over vast areas, and can create severe problems such as degradation of agriculture or natural environment sometimes depriving people and animals of water supply. In this paper, the authors present a method for determining the area of influence of a groundwater depression cone resulting from prolonged drainage, by means of satellite images in optical, near infrared and thermal infrared bands from TM sensor (Thematic Mapper) and ETM+ sensor (Enhanced Thematic Mapper +) placed on Landsat 5 and Landsat 7 satellites. The research area was Szczercowska Valley (Pol. Kotlina Szczercowska), Central Poland, located within a range of influence of a groundwater drainage system of the lignite coal mine in Belchatow. It is the biggest lignite coal mine in Poland and one of the largest in Europe exerting an enormous impact on the environment. The main method of satellite data analysis for determining soil moisture, was the so-called triangle method. This method, based on TVDI (Temperature Vegetation Dryness Index) was supported by additional spatial analysis including ordinary kriging used in order to combine fragmentary information obtained from areas covered by meadows. The results obtained are encouraging and confirm the usefulness of the triangle method not only for soil moisture determination but also for assessment of the temporal and spatial changes in the area influenced by the groundwater depression cone. The range of impact of the groundwater depression cone determined by means of above-described remote sensing analysis shows good agreement with that determined by ground measurements. The developed satellite method is much faster and cheaper than in-situ measurements, and allows for systematic monitoring of the vast area in the vicinity of Belchatow lignite mine. Besides, this method could be useful as a helper in in-situ measurement allowing a significant reduction of the number of in-situ measurements by performing them only within problematic areas. Hence, the triangle method can be used as an effective supplement to field measurements. Although the research area is located in Poland, in the vicinity of lignite mine, the method of observation of depression cones provided in this study is universal and effective, and therefore could also be useful to an international audience. Copyright © 2015 Elsevier Ltd. All rights reserved.
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NASA Astrophysics Data System (ADS)
Vyborova, Oxana
2010-05-01
The fertility of soil is a capacity for ensuring plants by water, nutrients, air and capacity for making optimal conditions for growth and development of plants. The result of it is a yield. The main characteristic of fertility of soil is maintenance of humus. The humus is important part of organic matter. The supporting of soil fertility is impossible by traditional methods. The amount of receiving mineral fertilizers in agriculture will not increase in future, because mineral fertilizers are very expensive. The mineral fertilizers don't influence on maintenance of total amount of humus in soil and improve the circulation of nutrients. Every hectare of fields have to receive no less than 8-10 tons of organic fertilizers, therefore we will have self-supporting balance of humus and the fertility of soils will be increasing. Consequently we are looking for new types of organic materials and we include them in modern agro technologies. One of them is an organomineral fertilizer (lignitic materials). The humic chemicals in the form of lignitic materials of natrium, potassium and ammonium are permitted for using them in agriculture at the beginning of 1984. The Department of agriculture in Russian Federation considered the problem of using humic chemicals and made a decision to use them on the fields of our country, because the lignitic materials can restore the fertility of our fields. The lignitic materials increase the amount of spore-forming bacteria, mold fungi and actinomycete. Therefore the organic decomposition occurs more strongly, the processes of humification increase the speed and the amount of humus rises in the soil. The new forming humus has a high biological activity and it improves chemical and physical soil properties. The addition of lignitic materials in soil activates different groups of microorganisms, which influence on mobilization of nutrients and transformation from potential to effective fertility. The inclusion of humic fertilizers improves physical, physicochemical properties of soils, its air, water and thermal rate. Humic acids with mineral and organomineral particles of soil form the soil absorbent complex. The inclusion of humic fertilizers promotes the process when humic substances form a very valuable water-stable clumpy-granular structure, which improves water-carrying and water-holding capacity, its air permeability by agglutination of mineral particles with each other. The soils, where humic fertilizers are carried in soils regularly, are more stable for influence of chemical polluting substances (for example, radioactive nuclides, heavy metals, pesticides) than poor soils. The inclusion of humic fertilizers is very important in period of urbanization and cropping on the plough-lands not far from a big industrial area. The lignitic materials tie together the detrimental compounds formed the insoluble complex in soil solution. The detrimental compounds don't go into plants, subsoil waters and atmosphere. The lignitic watering of soils (in concentration from 0.1 to 0.01%) increases biological activity of soil in a man-caused zones and it promotes to stability of plants to detrimental emission of enterprises. Today the problem of processing of sugar-beet industry is very important. In the result of storing sugar-beet wastes the pollution of environment is occurred, examples of this pollution are gassing, salinization of soils and ground waters by filtrational sediments. One of these wastes is defecation sludge. The defecation sludge consists of CaCO3, organic matter, nitrogen, phosphorus, potassium and microelements. The technology of receiving N-Ca fertilizer based on defecate was developed because of impossibility of using this waste in pure form. For available data, using of these fertilizers improves the soil fertility and degree of pollution by heavy metals don't exceed an acceptance limits.
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Discrimination of unique biological communities in the Mississippi lignite belt
NASA Technical Reports Server (NTRS)
Miller, W. F. (Principal Investigator); Cutler, J. D.
1981-01-01
Small scale hardcopy LANDSAT prints were manually interpreted and color infrared aerial photography was obtained in an effort to identify and map large contiguous areas of old growth hardwood stands within Mississippi's lignite belt which do not exhibit signs of recent disturbance by agriculture, grazing, timber harvesting, fire, or any natural catastrophe, and which may, therefore, contain unique or historical ecological habitat types. An information system using land cover classes derived from digital LANDSAT data and containing information on geology, hydrology, soils, and cultural activities was developed. Using computer-assisted land cover classifications, all hardwood remnants in the study area which are subject to possible disturbance from surface mining were determined. Twelve rare plants were also identified by botanists.
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Comparison of coal reactivityduring conversion into different oxidizing medium
NASA Astrophysics Data System (ADS)
Korotkikh, A. G.; Slyusarskiy, K. V.; Larionov, K. B.; Osipov, V. I.
2016-10-01
Acoal conversion process of different coal samples into three different types of oxidizing medium (argon, air and steam) were studied by means of thermogravimetry. Two coal types with different metamorphism degree (lignite and bituminous coal) were used. The experimental procedure was carried out in non-isothermal conditions in temperature range from 373 K to 1273 K with 20 K/min heating rate. Purge gas consisted of argon and oxidizer with volumetric ratio 1:24 and had 250 ml/min flow rate.The ignition and burnout indexes were calculated to evaluate sample reactivity at different oxidizing mediums. The highest reactivity coefficient values in same atmosphere were obtained for lignite. It was caused by higher particle special surface area and volatile matter content.
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NASA Astrophysics Data System (ADS)
Dedinec, A.; Jovanovski, B.; Gajduk, A.; Markovska, N.; Kocarev, L.
2016-05-01
We consider an integration of renewable energy into transport and electricity sectors through vehicle to grid (V2G) technologies for an energy system that is predominantly based on lignite. The national energy system of Macedonia is modeled using EnergyPLAN which integrates energy for electricity, transport and heat, and includes hourly fluctuations in human needs and the environment. We show that electric-vehicles can provide the necessary storage enabling a fully renewable energy profile for Macedonia that can match the country's growing demand for energy. Furthermore, a large penetration of electric vehicles leads to a dramatic reduction of 47% of small particles and other air pollutants generated by car traffic in 2050.
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Ground fissures in the area of Mavropigi Village (N. Greece): Seismotectonics or mining activity?
NASA Astrophysics Data System (ADS)
Kalogirou, Eleni; Tsapanos, Theodoros; Karakostas, Vassilios; Marinos, Vassilios; Chatzipetros, Alexandros
2014-12-01
In the beginning of July 2010, a ground fissure was observed in the field near the village of Mavropigi (Northern Greece) and specifically in its NW side. Later on (early September), a second ground fissure was perceived, close and almost parallel to the first one and very close to the limits of the lignite exploitation mine (by the Public Power Corporation, PPC). It was observed that the village of Mavropigi slides away slowly towards the PPC lignite mine. Geological, seismological, as well as geotechnical survey in the field indicated that the phenomenon is related to the coal mining exploitation in the near vicinity of the village rather than to any seismotectonic activity in the surrounding area.
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Preparation and Evaluation of Adsorbents from Coal and Irvingia gabonensis Seed Shell
NASA Astrophysics Data System (ADS)
Ezeokonkwo, Mercy A.; Ofor, Okechukwu F.; Ani, Julius U.
2017-12-01
The adsorption of Cd(II) and Pb(II) ions on adsorbents prepared from sub-bituminous coal, lignite and a blend of coal and Irvingia gabonensis seed shells was investigated. Fourier transform infrared, scanning electron microscope and X-ray fluorescence analyses implicated hydroxyl, carbonyl, Al2O3 and SiO2 as being responsible for binding the metal ions on the porous adsorbents. The optimum adsorption of carbonized lignite for the removal of Cd(II) and Pb(II) ions from aqueous media were 80.93% and 87.85%, respectively. Batch adsorption was done by effect of adsorbent dosage, pH, contact time, temperature, particle size, and initial concentration. Equilibrium for the removal of Pb(II) and Cd(II) was established within 100 and 120 min respectively. Blending the lignite-derived adsorbent with Irvingia gabonensis seed shell improved the performance significantly. More improvement was observed on modification of the blend using NaOH and H3PO4. Pb(II) was preferentially adsorbed than Cd(II) in all cases. Adsorption of Cd(II) and Pb(II) ions followed Langmuir isotherm. The kinetics of adsorption was best described by pseudo-second order model. The potential for using a blend of coal and agricultural byproduct (Irvingia gabonensis seed shell) was found to be a viable alternative for removal of toxic heavy metals from aqueous solutions.
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The solubilization of low-ranked coals by microorganisms
DOE Office of Scientific and Technical Information (OSTI.GOV)
Strandberg, G.W.
1987-07-09
Late in 1984, our Laboratory was funded by the Pittsburgh Energy Technology Center, US Department of Energy, to investigate the potential utility of microorganisms for the solubilization of low-ranked coals. Our approach has been multifacited, including studies of the types of microorganisms involved, appropriate conditions for their growth and coal-solubilization, the suceptibility of different coals to microbial action, the chemical and physical nature of the product, and potential bioprocess designs. A substantial number of fungal species have been shown to be able to solubilize coal. Cohen and Gabrielle reported that two lignin-degrading fungi, Polyporous (Trametes) versicolor and Poria monticola couldmore » solubilize lignite. Ward has isolated several diverse fungi from nature which are capable of degrading different lignites, and our Laboratory has isolated three coal-solubilizing fungi which were found growing on a sample of Texas lignite. The organisms we studied are shown in Table 1. The perceived significance of lignin degradation led us to examine two lignin-degrading strains of the genus Streptomyces. As discussed later, these bacteria were capable of solubilizing coal; but, in the case of at least one, the mechanism was non-enzymatic. The coal-solubilizing ability of other strains of Streptomyces was recently reported. Fakoussa and Trueper found evidence that a strain of Pseudomonas was capble of solubizing coal. It would thus appear that a diverse array of microorganisms possess the ability to solubilize coal. 16 refs.« less
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Patel, Mitesh J; Tipre, Devayani R; Dave, Shailesh R
2009-12-01
An extremely acidic mine drainage (AMD) water sample was collected in 1998 and 2008 from Panandhro lignite mine, Gujarat, India. The yeast isolated from this sample was identified using mini API identification system, as a member of genus Candida. The major cellular fatty acids detected by FAME from the isolate are C(16:0) and C(18:2) (cis 9,12)/C(18:0alpha) as 25.23 and 19.5%, respectively. The isolate was identified as Candida digboiensis by 18S rRNA gene sequence analysis and designated as Candida digboiensis SRDyeast1. Phylogenetic analysis using D1/D2 variable domains showed that the closest relative of this strain is Candida blankii with 3% divergence. This organism has been reported for the first time from the lignite mine AMD sample, and for cellular fatty acid analysis. This yeast is able to survive in the AMD sample preserved at 10-42 degrees C temperature since last 10 years along with iron oxidizing microorganisms. It can grow in the presence of 40% glucose, 10% NaCl and in the pH range of 1 to 10. The isolate is capable of producing enzymes like protease and lipase. This isolate differs from the type strain Candida digboiensis in as many as six physiological and metabolic characteristics.
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Valorization of lignite combustion residues and ferroalumina in the production of aggregates.
Anagnostopoulos, I M; Stivanakis, V E; Angelopoulos, G N; Papamantellos, D C
2010-02-15
The present research study investigates the synergy of industrial solid by-products from lignite combustion (fly ash and bottom ash) and aluminum production (ferroalumina) in the production of lightweight aggregates (LWA). The process consists of two stages, pelletization and sintering. Bottom ash (BA) is used as the principal raw material in mixtures while ferroalumina (FAL) is added in lower percentages (5-30 wt%). BA carbon content is used as the fuel of sintering process in high temperatures, around 1250 degrees C, and gas generation is responsible for porous structure formation. Physical properties such as porosity, water absorption and bulk density, of sintering products are measured. Increase of FAL percentage in sintering mixtures results in decrease of porosity from 61% to 35% and of water absorption from 61% to 21% and in increase of bulk density from 1.02 g/cm(3) to 1.80 g/cm(3) of the produced aggregates. Aggregates produced by FAL addition up to 20 wt% are characterized as LWA. Aggregates formed are used in the production of concrete specimens. Compressive strength of concrete increases by increasing FAL addition in aggregates from 5 wt% to 15 wt% (highest strength value), while decrease by increasing FAL addition from 20 wt% to 30 wt%. FAL addition in lignite ashes sintering mixtures (up to 15 wt%) is considered as an important parameter for enhancing aggregates strength.
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Direct comparison of XAFS spectroscopy and sequential extraction for arsenic speciation in coal
Huggins, Frank E.; Huffman, G.P.; Kolker, A.; Mroczkowski, S.; Palmer, C.A.; Finkelman, R.B.
2000-01-01
The speciation of arsenic in an Ohio bituminous coal and a North Dakota lignite has been examined by the complementary methods of arsenic XAFS spectroscopy and sequential extraction by aqueous solutions of ammonium acetate, HCl, HF, and HNO3. In order to facilitate a more direct comparison of the two methods, the arsenic XAFS spectra were obtained from aliquots of the coal prepared after each stage of the leaching procedure. For the aliquots, approximately linear correlations (r2 > 0.98 for the Ohio coal, > 0.90 for the ND lignite) were observed between the height of the edge-step in the XAFS analysis and the concentration of arsenic measured by instrumental neutron activation analysis. Results from the leaching sequence indicate that there are two major arsenic forms present in both coals; one is removed by leaching with HCl and the other by HNO3. Whereas the XAFS spectral signatures of the arsenic leached by HCl are compatible with arsenate for both coals, the arsenic leached by HNO3 is identified as arsenic associated with pyrite for the Ohio coal and as an As3+ species for the North Dakota lignite. Minor arsenate forms persist in both coals after the final leaching with nitric acid. The arsenate forms extracted in HCl are believed to be oxidation products derived from the other major arsenic forms upon exposure of the pulverized coals to air.
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Coal-Quality Information - Key to the Efficient and Environmentally Sound Use of Coal
Finkleman, Robert B.
1997-01-01
The rock that we refer to as coal is derived principally from decomposed organic matter (plants) consisting primarily of the element carbon. When coal is burned, it produces energy in the form of heat, which is used to power machines such as steam engines or to drive turbines that produce electricity. Almost 60 percent of the electricity produced in the United States is derived from coal combustion. Coal is an extraordinarily complex material. In addition to organic matter, coal contains water (up to 40 or more percent by weight for some lignitic coals), oils, gases (such as methane), waxes (used to make shoe polish), and perhaps most importantly, inorganic matter (fig. 1). The inorganic matter--minerals and trace elements--cause many of the health, environmental, and technological problems attributed to coal use (fig. 2). 'Coal quality' is the term used to refer to the properties and characteristics of coal that influence its behavior and use. Among the coal-quality characteristics that will be important for future coal use are the concentrations, distribution, and forms of the many elements contained in the coal that we intend to burn. Knowledge of these quality characteristics in U.S. coal deposits may allow us to use this essential energy resource more efficiently and effectively and with less undesirable environmental impact.
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Coal desulfurization by low temperature chlorinolysis, phase 1
NASA Technical Reports Server (NTRS)
Kalvinskas, J. J.; Hsu, G. C.; Ernest, J. B.; Andress, D. F.; Feller, D. R.
1977-01-01
The reported activity covers laboratory scale experiments on twelve bituminous, sub-bituminous and lignite coals, and preliminary design and specifications for bench-scale and mini-pilot plant equipment.
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30 CFR 75.380 - Escapeways; bituminous and lignite mines.
Code of Federal Regulations, 2010 CFR
2010-07-01
...) Underground transformer stations, battery charging stations, substations, and rectifiers except— (A) Where... rectifiers and power centers with transformers that are either dry-type or contain nonflammable liquid...
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Energy production for environmental issues in Turkey
NASA Astrophysics Data System (ADS)
Yuksel, Ibrahim; Arman, Hasan; Halil Demirel, Ibrahim
2017-11-01
Due to the diversification efforts of energy sources, use of natural gas that was newly introduced into Turkish economy, has been growing rapidly. Turkey has large reserves of coal, particularly of lignite. The proven lignite reserves are 8.0 billion tons. The estimated total possible reserves are 30 billion tons. Turkey, with its young population and growing energy demand per person, its fast growing urbanization, and its economic development, has been one of the fast growing power markets of the world for the last two decades. It is expected that the demand for electric energy in Turkey will be 580 billion kWh by the year 2020. Turkey's electric energy demand is growing about 6-8% yearly due to fast economic growing. This paper deals with energy demand and consumption for environmental issues in Turkey.
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NASA Astrophysics Data System (ADS)
Güner, Tuncay H.; Bouchal, Johannes M.; Köse, Nesibe; Denk, Thomas
2017-04-01
During the course of an ongoing palaeobotanical investigation of the lignite mines of the Yataǧan Basin, Muǧla province, Turkey, the fossil leaves of the Eskihisar lignite mine were analysed using the Climate Leaf Analysis Multivariate Program (CLAMP). The investigated fossil leaves derive from the marls and clayey limestones (Sekköy Member) overlying the exploited lignite seam (uppermost Turgut Member). The age of the studied sedimentary rocks is well constrained by vertebrate fossils occuring in the main lignite seam (MN6 → Gomphoterium angustidens Cuvier, 1817; Percrocuta miocenica Pavlov & Thenius, 1965) and at the Yenieskihisar Mammal locality (MN7/8, uppermost Sekköy Member). 719 specimens were measured and assigned to 65 leaf morphotypes. Using this data, CLAMP reconstructed the following climate parameters: mean annual temperature (MAT) 12.58 (+/-1.5)°C, warm month mean temperature (WMMT) 23.72 (+/-2.5)°C, cold month mean temperature (WMMT) 2.29 (+/-2)°C, length of growing season (LGS) 7.52 (+/-0.75) month, mean growing season precipitation (GSP) 130.1 (+/-40) cm, precipitation during the three wettest months (3-WET) 67 (+/-25) cm, precipitation during the three driest months (3-DRY) 20.4 (+/-7.5) cm. The reconstructed parameters are too cool for tropical climates (the 18˚ C winter isotherm being a threshold for tropical climates) and indicate temperate conditions; climates fitting these parameters (Cfb according to the Köppen-Geiger climate classification) can be found today in regions known as "Tertiary relict areas" (e.g. Black sea coast of Northeast Turkey, eastern China, Japan). Based on a substantial amount of rainfall during the three driest months, it is further possible to exclude markedly seasonal climates such as a summer-dry and winter-wet Mediterranean climate and a summer-wet and winter-dry monsoon climate as commonly found along the southern foothills of the Himalayas and in southwestern China. Instead, a fully humid Cf climate is proposed that has only a weak seasonality in precipitation (lower precipitation in winter). The findings of our study provide valuable information for inferring palaeoenvironments of middle Miocene rich ungulate faunas in western Turkey (e.g. Paşalar), for which seasonal tropical and subtropical forest communities have been proposed (Andrews, 1990). The fossil floras of the Tınaz and Salihpaşalar lignite mines, representing the Tınaz sub-basin and the main basin of the wider Yataǧan Basin, are investigated at the moment, and a synthesis paper combining and comparing evidence from the macro floral and palynological data is soon to be submitted. Andrews. (1990) Palaeoecology of the Miocene fauna from Paşalar, Turkey. Journal of Human evolution 19:569-582.
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Role of NSO compounds during primary cracking of a Type II kerogen and a Type III lignite
Behar, F.; Lorant, F.; Lewan, M.
2008-01-01
The aim of this work is to follow the generation of NSO compounds during the artificial maturation of an immature Type II kerogen and a Type III lignite in order to determine the different sources of the petroleum potential during primary cracking. Experiments were carried out in closed system pyrolysis in the temperature range from 225 to 350 ??C. Two types of NSOs were recovered: one is soluble in n-pentane and the second in dichloromethane. A kinetic scheme was optimised including both kerogen and NSO cracking. It was validated by complementary experiments carried out on isolated asphaltenes generated from the Type II kerogen and on the total n-pentane and DCM extracts generated from the Type III lignite. Results show that kerogen and lignite first decompose into DCM NSOs with minor generation of hydrocarbons. Then, the main source of petroleum potential originates from secondary cracking of both DCM and n-pentane NSOs through successive decomposition reactions. These results confirm the model proposed by Tissot [Tissot, B., 1969. Premie??res donne??es sur les me??canismes et la cine??tique de la formation du pe??trole dans les bassins se??dimentaires. Simulation d'un sche??ma re??actionnel sur ordinateur. Oil and Gas Science and Technology 24, 470-501] in which the main source of hydrocarbons is not the insoluble organic matter, but the NSO fraction. As secondary cracking of the NSOs largely overlaps that of the kerogen, it was demonstrated that bulk kinetics in open system is a result of both kerogen and NSO cracking. Thus, another kinetic scheme for primary cracking in open system was built as a combination of kerogen and NSO cracking. This new kinetic scheme accounts for both the rate and amounts of hydrocarbons generated in a closed pyrolysis system. Thus, the concept of successive steps for hydrocarbon generation is valid for the two types of pyrolysis system and, for the first time, a common kinetic scheme is available for extrapolating results to natural case studies. ?? 2007 Elsevier Ltd. All rights reserved.
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NASA Astrophysics Data System (ADS)
Schaaf, Wolfgang
2015-04-01
Lignite mining in Lusatia has a history of over 100 years. Open-cast mining directly affected an area of 1000 km2. Since 20 years we established an ecosystem oriented approach to evaluate the development and site characteristics of post-mining areas mainly restored for agricultural and silvicultural land use. Water and element budgets of afforested sites were studied under different geochemical settings in a chronosequence approach (Schaaf 2001), as well as the effect of soil amendments like sewage sludge or compost in restoration (Schaaf & Hüttl 2006). Since 10 years we also study the development of natural site regeneration in the constructed catchment Chicken Creek at the watershed scale (Schaaf et al. 2011, 2013). One of the striking characteristics of post-mining sites is a very large small-scale soil heterogeneity that has to be taken into account with respect to soil forming processes and element cycling. Results from these studies in combination with smaller-scale process studies enable to evaluate the long-term effect of restoration measures and adapted land use options. In addition, it is crucial to compare these results with data from undisturbed, i.e. non-mined sites. Schaaf, W., 2001: What can element budgets of false-time series tell us about ecosystem development on post-lignite mining sites? Ecological Engineering 17, 241-252. Schaaf, W. and Hüttl, R. F., 2006: Direct and indirect effects of soil pollution by lignite mining. Water, Air and Soil Pollution - Focus 6, 253-264. Schaaf, W., Bens, O., Fischer, A., Gerke, H.H., Gerwin, W., Grünewald, U., Holländer, H.M., Kögel-Knabner, I., Mutz, M., Schloter, M., Schulin, R., Veste, M., Winter, S. & Hüttl, R.F., 2011: Patterns and processes of initial terrestrial-ecosystem development. Journal of Plant Nutrition and Soil Science, 174, 229-239. Schaaf, W., Elmer, M., Fischer, A., Gerwin, W., Nenov, R., Pretsch, H. and Zaplate, M.K., 2013: Feedbacks between vegetation, surface structures and hydrology during initial development of the artificial catchment `Chicken Creek'. Procedia Environmental Sciences 19, 86-95.
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Infiltration and soil erosion modelling on Lausatian post mine sites
NASA Astrophysics Data System (ADS)
Kunth, Franziska; Schmidt, Jürgen
2013-04-01
Land management of reclaimed lignite mine sites requires long-term and safe structuring of recultivation areas. Erosion by water leads to explicit soil losses, especially on heavily endangered water repellent and non-vegetated soil surfaces. Beyond that, weathering of pyrite-containing lignite burden dumps causes sulfuric acid-formation, and hence the acidification of groundwater, seepage water and surface waters. Pyrite containing sediment is detached by precipitation and transported into worked-out open cuts by draining runoff. In addition to ground water influence, erosion processes are therefore involved in acidification of surface waters. A model-based approach for the conservation of man-made slopes of post mining sites is the objective of this ongoing study. The study shall be completed by modeling of the effectiveness of different mine site recultivation scenarios. Erosion risks on man-made slopes in recultivation areas should be determined by applying the physical, raster- and event based computer model EROSION 2D/3D (Schmidt, 1991, 1992; v. Werner, 1995). The widely used erosion model is able to predict runoff as well as detachment, transport and deposition of sediments. Lignite burden dumps contain hydrophobic substances that cover soil particles. Consequently, these soils show strong water repellency, which influences the processes of infiltration and soil erosion on non-vegetated, coal containing dump soils. The influence of water repellency had to be implemented into EROSION 2D/3D. Required input data for soil erosion modelling (e.g. physical soil parameters, infiltration rates, calibration factors, etc.) were gained by soil sampling and rainfall experiments on non-vegetated as well as recultivated reclaimed mine sites in the Lusatia lignite mining region (southeast of Berlin, Germany). The measured infiltration rates on the non-vegetated water repellent sites were extremely low. Therefore, a newly developed water repellency-factor was applied to depict infiltration and erosion processes on water repellent dump soils. For infiltration modelling with EROSION 2D calibration factors (e.g. water repellency factor, skin-factor, etc.) were determined in different steps by calibrating computer modelled infiltration, respectively volume rate of flow to the measured data.
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Microbial desulphurization of Turkish lignites by White Rot Fungi
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pinar Aytar; Mesut Sam; Ahmet Cabuk
2008-03-15
Biodesulphurization experiments were carried out with Tuncbilek lignite, characterized by high sulfur content (2.59%) by using Trametes versicolor ATCC 200801 and Phanerochaete chrysosporium ME 446. At fungal biomass studies, the effects of various parameters on fungal desulphurization of coals such as pH, temperature, pulp density, incubation time, and sterilization were investigated for both microorganisms. The maximum desulphurization (40%) was observed after 6 days of incubation at 35{sup o}C for T. versicolor. The optimum pH was measured at 6, and the agitation rate was fixed at 125 rpm. The pulp density was found as 5% (w/v) for the high extent ofmore » desulphurization. Also, calorific value did not change during this experiment. However, the ash and metal contents of coal were eliminated. 30 refs., 6 figs., 2 tabs.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
ARCTECH has developed a novel process (MicGAS) for direct, anaerobic biomethanation of coals. Biomethanation potential of coals of different ranks (Anthracite, bitumious, sub-bitumious, and lignites of different types), by various microbial consortia, was investigated. Studies on biogasification of Texas Lignite (TxL) were conducted with a proprietary microbial consortium, Mic-1, isolated from hind guts of soil eating termites (Zootermopsis and Nasutitermes sp.) and further improved at ARCTECH. Various microbial populations of the Mic-1 consortium carry out the multi-step MicGAS Process. First, the primary coal degraders, or hydrolytic microbes, degrade the coal to high molecular weight (MW) compounds. Then acedogens ferment themore » high MW compounds to low MW volatile fatty acids. The volatile fatty acids are converted to acetate by acetogens, and the methanogens complete the biomethanation by converting acetate and CO{sub 2} to methane.« less
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NASA Astrophysics Data System (ADS)
Åberg, G.; Charalampides, G.; Fosse, G.; Hjelmseth, H.
Stable lead isotopes are used to illustrate the relation source-receptor and to differentiate between sources of pollution in Greece. Air filters collected in the Kozani-Ptolemais lignite mining area, West Macedonia, point to an impact from gasoline lead as well as lead from the combustion of lignite. This is supported by lead isotope data of wheat grown on reclaimed land. Lead isotope analyses of contemporary teeth from the Lavrio sulphide mining area, southeast of Greece, show the imprint of previous mining activities as well as traffic emissions. Moreover, the Lavrio teeth can be distinguished from one tooth from Athens; the Athens tooth show a stronger impact of gasoline lead. Lead data also imply that the Greek top soil is contaminated by air pollution from earlier sulphide mining and smelting since Hellenic and Roman times.
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Preliminary report on the lignite resources of the Niobe area, Burke and Ward counties, North Dakota
Owen, Hal E.
1977-01-01
Two lignite beds, the Niobe and the Bonus, occur at strippable depths within the Niobe area. The Niobe bed averages 5 feet (1.5 meters) in thickness and the Bonus bed averages 8 feet (2.4 meters) in thickness. These beds lie in the lower part of the Sentinel Butte Member of the Fort Union Formation (Paleocene). The demonstrated resources of both beds combined is 122 million tons (110 million tonnes), all of which are under less than 120 feet (37 meters) of overburden. The overburden consists of glacial till and shale. The lateral continuity of the coal has been locally interrupted by faulting, glacial outwash channels, and erosion. Folding and/or faulting occurs parallel to the Missouri Coteau escarpment and faulting occurs roughly perpendicular to the escarpment.
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Code of Federal Regulations, 2012 CFR
2012-07-01
... old section 203(b) program (36 FR 20601, October 27, 1971), or under § 90.3 (Part 90 option; notice of... area bituminous coal, lignite, or anthracite from its natural deposits in the earth by any means or...
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Code of Federal Regulations, 2013 CFR
2013-07-01
... old section 203(b) program (36 FR 20601, October 27, 1971), or under § 90.3 (Part 90 option; notice of... area bituminous coal, lignite, or anthracite from its natural deposits in the earth by any means or...
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Code of Federal Regulations, 2011 CFR
2011-07-01
... old section 203(b) program (36 FR 20601, October 27, 1971), or under § 90.3 (Part 90 option; notice of... area bituminous coal, lignite, or anthracite from its natural deposits in the earth by any means or...
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Code of Federal Regulations, 2010 CFR
2010-07-01
... old section 203(b) program (36 FR 20601, October 27, 1971), or under § 90.3 (Part 90 option; notice of... area bituminous coal, lignite, or anthracite from its natural deposits in the earth by any means or...
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Code of Federal Regulations, 2014 CFR
2014-07-01
... old section 203(b) program (36 FR 20601, October 27, 1971), or under § 90.3 (Part 90 option; notice of... area bituminous coal, lignite, or anthracite from its natural deposits in the earth by any means or...
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The role of coal in industrialization: A case study of Nigeria
DOE Office of Scientific and Technical Information (OSTI.GOV)
Akarakiri, J.B.
1989-01-01
Coal is a mineral matter found in layers or beds in sedimentary rocks. It is a very highly variable substance. In addition to the variations from lignite to bituminous and anthracite, there are vast differences in its heating value, amount of volatiles, sulfur, moisture and so on. The chemical and physical properties of coal make it an important industrial raw material. There is proven 639 million tonnes of coal reserves in Nigeria. This paper examines the potential and current role of coal in the industrialization of Nigeria. Industries are now dependent on fuel oil as a source of fuel becausemore » of its economic and technological advantages over coal. Coal is a source of industrial energy for the future after the known oil reserves might have been exhausted. In the short term, coal can be used as a material for chemicals, iron and steel production as well as a substitute for wood energy in the process of industrialization.« less
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Evaluation of Rare Earth Element Extraction from North Dakota Coal-Related Feed Stocks
NASA Astrophysics Data System (ADS)
Laudal, Daniel A.
The rare earth elements consist of the lanthanide series of elements with atomic numbers from 57-71 and also include yttrium and scandium. Due to their unique properties, rare earth elements are crucial materials in an incredible array of consumer goods, energy system components and military defense applications. However, the global production and entire value chain for rare earth elements is dominated by China, with the U.S. currently 100% import reliant for these critical materials. Traditional mineral ores including previously mined deposits in the U.S., however, have several challenges. Chief among these is that the content of the most critical and valuable of the rare earths are deficient, making mining uneconomical. Further, the supply of these most critical rare earths is nearly 100% produced in China from a single resource that is only projected to last another 10 to 20 years. The U.S. currently considers the rare earths market an issue of national security. It is imperative that alternative domestic sources of rare earths be identified and methods developed to produce them. Recently, coal and coal byproducts have been identified as one of these promising alternative resources. This dissertation details a study on evaluation of the technical and economic feasibility of rare earth element recovery from North Dakota lignite coal and lignite-related feedstocks. There were four major goals of this study: i) identify lignite or lignite-related feedstocks with total rare earth element content above 300 parts per million, a threshold dictated by the agency who funded this research as the minimum for economic viability, ii) determine the geochemistry of the feedstocks and understand the forms and modes of occurrence of the rare earth elements, information necessary to inform the development of extraction and concentration methods, iii) identify processing methods to concentrate the rare earth elements from the feedstocks to a target of two weight percent, a value that would be sufficient to leverage existing separation and refining methods developed for the traditional mineral ore industry, and iv) develop a process that is economically viable and environmentally benign. To achieve these overall goals, and to prove or disprove the research hypotheses, the research scope was broken down into three main efforts: i) sampling and characterization of potential feedstocks, ii) laboratory-scale development and testing of rare earth element extraction and concentration methods, and iii) process design and technical and economic feasibility evaluation. In total, 174 unique samples were collected, and several locations were identified that exceeded the 300 ppm total rare earth elements target. The results showed that on a whole sample basis, the rare earths are most concentrated in the clay-rich sediments associated with the coal seams, but on an ash basis in certain locations within certain coal seams the content is significantly higher, an unexpected finding given prior research. At Falkirk Mine near Underwood, North Dakota three coal seams were found to have elevated levels of rare earths, ranging from about 300 to 600 ppm on an ash basis. Additionally, exceptionally high rare earths content was found in samples collected from an outcropping of the Harmon-Hansen coal zone in southwestern North Dakota that contained 2300 ppm on an ash basis. The results dictated that extraction and concentration methods be developed for these rare earth element-rich coals, instead of the mineral-rich sediments. This effort also found that at a commercial-scale, due to non-uniformity of the rare earths content stratigraphically in the coal seams, selective mining practices will be needed to target specific locations within the seams. The bulk mining and blending practices as Falkirk Mine result in a relatively low total rare earths content in the feed coal entering the Coal Creek Power Station adjacent to the mine. Characterization of the coal samples identified that the predominant modes of rare earths occurrence in the lignite coals are associations with the organic matter, primarily as coordination complexes and a lesser amount as ion-exchangeable cations on oxygen functional groups. Overall it appears that about 80-95% of rare earths content in North Dakota lignite is organically associated, and not present in mineral forms, which due to the weak organic bonding, presented a unique opportunity for extraction. The process developed for extraction of rare earths was applied to the raw lignite coals instead of fly ash or other byproducts being investigated extensively in the literature. Rather, the process uses a dilute acid leaching process to strip the organically associated rare earths from the lignite with very high efficiency of about 70-90% at equilibrium contact times. Although the extraction kinetics are quite fast given commercial leaching operations, there is some tradeoff between extraction efficiency and contact time. (Abstract shortened by ProQuest.).
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Underground gas storage in the Leyden lignite mine
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meddles, R.M.
1978-01-01
Underground gas storage in the Leyden lignite mine by Public Service Co. of Colorado was preceded by careful studies of mine records with respect to geologic conditions and investigation of the gas-sealing potential of the rocks surrounding the cavern. The water level in shaft No. 3 in Sept. 1958 was about 100 ft above the coal seam at that point. Wells were drilled into the mine up-dip (east) of the structurally highest point that a mine shaft intersected the coal seams, and gas was injected into the mine, using the mine water as a seal. At least the up-dip partmore » of the mine was gas-tight, and tests were expanded to the rest of the mine, which also proved to be gas-tight. All that remained to complete the preparation of the mine for permanent gas storage was sealing of the old mine shafts.« less
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Inagaki, F; Hinrichs, K-U; Kubo, Y; Bowles, M W; Heuer, V B; Hong, W-L; Hoshino, T; Ijiri, A; Imachi, H; Ito, M; Kaneko, M; Lever, M A; Lin, Y-S; Methé, B A; Morita, S; Morono, Y; Tanikawa, W; Bihan, M; Bowden, S A; Elvert, M; Glombitza, C; Gross, D; Harrington, G J; Hori, T; Li, K; Limmer, D; Liu, C-H; Murayama, M; Ohkouchi, N; Ono, S; Park, Y-S; Phillips, S C; Prieto-Mollar, X; Purkey, M; Riedinger, N; Sanada, Y; Sauvage, J; Snyder, G; Susilawati, R; Takano, Y; Tasumi, E; Terada, T; Tomaru, H; Trembath-Reichert, E; Wang, D T; Yamada, Y
2015-07-24
Microbial life inhabits deeply buried marine sediments, but the extent of this vast ecosystem remains poorly constrained. Here we provide evidence for the existence of microbial communities in ~40° to 60°C sediment associated with lignite coal beds at ~1.5 to 2.5 km below the seafloor in the Pacific Ocean off Japan. Microbial methanogenesis was indicated by the isotopic compositions of methane and carbon dioxide, biomarkers, cultivation data, and gas compositions. Concentrations of indigenous microbial cells below 1.5 km ranged from <10 to ~10(4) cells cm(-3). Peak concentrations occurred in lignite layers, where communities differed markedly from shallower subseafloor communities and instead resembled organotrophic communities in forest soils. This suggests that terrigenous sediments retain indigenous community members tens of millions of years after burial in the seabed. Copyright © 2015, American Association for the Advancement of Science.
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Bunnell, J.E.; Tatu, C.A.; Lerch, H.E.; Orem, W.H.; Pavlovic, N.
2007-01-01
High-molecular-weight organic compounds such as humic acids and/or fulvic acids that are naturally mobilized from lignite beds into untreated drinking-water supplies were suggested as one possible cause of Balkan endemic nephropathy (BEN) and cancer of the renal pelvis. A lab investigation was undertaken in order to assess the nephrotoxic potential of such organic compounds using an in vitro tissue culture model. Because of the infeasibility of exposing kidney tissue to low concentrations of organics for years in the lab, tangential flow ultrafiltration was employed to hyperconcentrate samples suitable for discerning effects in the short time frames necessitated by tissue culture systems. Effects on HK-2 kidney cells were measured using two different cell proliferation assays (MTT and alamarBlue). Results demonstrated that exposure of kidney tissue to high-molecular-weight organics produced excess cell death or proliferation depending on concentration and duration of exposure. Copyright ?? Taylor & Francis Group, LLC.
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Experimental Study of Hydrogasification of Lignite and Subbituminous Coal Chars
Gil, Stanisław
2015-01-01
The experimental facility for pressure hydrogasification research was adapted to the pressure of 10 MPa and temperature of 1300 K, which ensured repeatability of results and hydrogen heating to the process temperature. A hydrogasification reaction of chars produced from two rank coals was investigated at temperatures up to 1173 K, pressures up to 8 MPa, and the gas flow rates of 0.5–5 dmn 3/min. Reactivity of the “Szczerców” lignite char was found to be slightly higher than that of the subbituminous “Janina” coal char produced under the same conditions. A high value of the char reactivity was observed to a certain carbon conversion degree, above which a sharp drop took place. It was shown that, to achieve proper carbon conversion, the hydrogasification reaction must proceed at a temperature above 1200 K. PMID:26065028
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Vassallo, A.M.; Wilson, M.A.; Collin, P.J.; Oades, J.M.; Waters, A.G.; Malcolm, R.L.
1987-01-01
An examination of coals, coal tars, a fulvic acid, and soil fractions by solid-state 13C NMR spectrometry has demonstrated widely differing behavior regarding quantitative representation in the spectrum. Spin counting experiments on coal tars and the fulvic acid show that almost all the sample carbon is observed in both solution and solid-state NMR spectra. Similar experiments on two coals (a lignite and a bituminous coal) show that most (70-97%) of the carbon is observed; however, when the lignite is ion exchanged with 3% (w/w) Fe3+, the fraction of carbon observed drops to below 10%. In additional experiments signal intensity from soil samples is enhanced by a simple dithionite treatment. This is illustrated by 13C, 27Al, and 29Si solid-state NMR experiments on soil fractions. ?? 1987 American Chemical Society.
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Stabilisation of bank slopes that are prone to liquefaction in ecologically sensitive areas.
Nestler, P; Stoll, R D
2001-01-01
A consequence of lignite stripping in the Lusatia mining district (East Germany) is the backfilling of dumps that mainly consist of low-compacted fine and medium-grained sands. When the ground-water table, which had been lowered while stripping the coal, is rising again, these dumps might be affected by a settlement flow due to the liquefaction of soils. Common methods for stabilisation as, for instance, blasting or vibrator-jetting deep compaction, are not very useful in ecologically sensitive areas, where dumps have been afforested and embankment areas of residual lakes have developed into highly valuable biotopes. A new so-called air-impulse method in combination with directional horizontal drilling has been developed, which does not have a considerably negative impact on the vegetation during compaction. The experience gained during the first employment of this method at the lake "Katja", a residual lake of lignite stripping, is presented in this paper.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
McKeigue, J.; Da Cunha, A.; Severino, D.
Turkey's growing power market has attracted investors and project developers for over a decade, yet their plans have been dashed by unexpected political or financial crises or, worse, obstructed by a lengthy bureaucratic approval process. Now, with a more transparent retail electricity market, government regulators and investors are bullish on Turkey. Is Turkey ready to turn the power on? This report closely examine Turkey's plans to create a power infrastructure capable of providing the reliable electricity supplies necessary for sustained economic growth. It was compiled with on-the-ground research and extensive interview with key industrial and political figures. Today, hard coalmore » and lignite account for 21% of Turkey's electricity generation and gas-fired plants account for 50%. The Alfin Elbistan-B lignite-fired plant has attracted criticism for its lack of desulfurization units and ash dam facilities that have tarnished the industry's image. A 1,100 MW hard-coal fired plant using supercritical technology is under construction. 9 figs., 1 tab.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Ali Sinag; Melike Sungur; Mustafa Gullu
This study describes the detailed hydrocarbon type characterization of the tar (liquid phase) obtained by copyrolysis of Mustafa Kemal Paa (M.K.P.) lignite (Turkey) and low density polyethylene (LDPE) and by pyrolysis of coal and LDPE individually. Various spectroscopic techniques (gas chromatography-mass spectroscopy (GC-MS), nuclear magnetic resonance spectroscopy ({sup 1}H NMR), Fourier transform infrared spectroscopy (FTIR), and gel permeation chromatography (GPC)) are used for characterization, and the effect of the experimental conditions (temperature, lignite:low density polyethylene (LDPE) ratio, and catalyst) on the hydrocarbon distributions is discussed. The results show that the tars obtained by copyrolysis have similar properties with commercial gasolinemore » (especially in the presence of Red mud). Red mud and bentonite used as catalysts make a positive effect on the production of olefins instead aromatics. Polyethylene acts as a hydrogenation medium for the coal product as revealed by FTIR results. 18 refs., 9 figs., 5 tabs.« less
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The mineral base and productive capacities of metals and non-metals of Kosovo
NASA Astrophysics Data System (ADS)
Rizaj, M.; Beqiri, E.; McBow, I.; O'Brien, E. Z.; Kongoli, F.
2008-08-01
All historical periods of Kosovo—Ilirik, Roman, Medieval, Turkish, and former Yugoslavian—are linked with the intensive development of mining and metallurgy. This activity influenced and still is influencing the overall position of Kosovo as a country. For example, according to a 2006 World Bank report as well as other studies, Kosovo has potential lignite resources (geological reserves) of about 1.5 billion tonnes, which are ranked fifth in the world in importance. Other significant Kosovan mineral resources include lead, zinc, gold, silver, bauxite, and uranium, and rare metals accompanying those minerals, including indium, cadmium, thallium, gallium, and bismuth. These rare metals are of particular importance in developing advanced industrial technologies. Kosovo also has reserves of high-quality non-metals, including magnesite, quartz grit, bentonite, argil, talc, and asbestos. No database exists for these non-metal reserves, and further research and studies are needed.
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The mineral base and productive capacities of metals and non-metals of Kosovo
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rizaj, M.; Beqiri, E.; McBow, I.
2008-08-15
All historical periods of Kosovo - Ilirik, Roman, Medieval, Turkish, and former Yugoslavian - are linked with the intensive development of mining and metallurgy. This activity influenced and still is influencing the overall position of Kosovo as a country. For example, according to a 2006 World Bank report as well as other studies, Kosovo has potential lignite resources (geological reserves) of about 1.5 billion tonnes, which are ranked fifth in the world in importance. Other significant Kosovan mineral resources include lead, zinc, gold, silver, bauxite, and uranium, and rare metals accompanying those minerals, including indium, cadmium, thallium, gallium, and bismuth.more » These rare metals are of particular importance in developing advanced industrial technologies. Kosovo also has reserves of high-quality non-metals, including magnesite, quartz grit, bentonite, argil, talc, and asbestos. No database exists for these non-metal reserves, and further research and studies are needed.« less
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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.
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Bhagavatula, Abhijit; Huffman, Gerald; Shah, Naresh; ...
2014-01-01
The thermal evolution profiles and kinetic parameters for the pyrolysis of two Montana coals (DECS-38 subbituminous coal and DECS-25 lignite coal), one biomass sample (corn stover), and their blends (10%, 20%, and 30% by weight of corn stover) have been investigated at a heating rate of 5°C/min in an inert nitrogen atmosphere, using thermogravimetric analysis. The thermal evolution profiles of subbituminous coal and lignite coal display only one major peak over a wide temperature distribution, ~152–814°C and ~175–818°C, respectively, whereas the thermal decomposition profile for corn stover falls in a much narrower band than that of the coals, ~226–608°C. Themore » nonlinearity in the evolution of volatile matter with increasing percentage of corn stover in the blends verifies the possibility of synergistic behavior in the blends with subbituminous coal where deviations from the predicted yield ranging between 2% and 7% were observed whereas very little deviations (1%–3%) from predicted yield were observed in blends with lignite indicating no significant interactions with corn stover. In addition, a single first-order reaction model using the Coats-Redfern approximation was utilized to predict the kinetic parameters of the pyrolysis reaction. The kinetic analysis indicated that each thermal evolution profile may be represented as a single first-order reaction. Three temperature regimes were identified for each of the coals while corn stover and the blends were analyzed using two and four temperature regimes, respectively.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Bhagavatula, Abhijit; Huffman, Gerald; Shah, Naresh
The thermal evolution profiles and kinetic parameters for the pyrolysis of two Montana coals (DECS-38 subbituminous coal and DECS-25 lignite coal), one biomass sample (corn stover), and their blends (10%, 20%, and 30% by weight of corn stover) have been investigated at a heating rate of 5°C/min in an inert nitrogen atmosphere, using thermogravimetric analysis. The thermal evolution profiles of subbituminous coal and lignite coal display only one major peak over a wide temperature distribution, ~152–814°C and ~175–818°C, respectively, whereas the thermal decomposition profile for corn stover falls in a much narrower band than that of the coals, ~226–608°C. Themore » nonlinearity in the evolution of volatile matter with increasing percentage of corn stover in the blends verifies the possibility of synergistic behavior in the blends with subbituminous coal where deviations from the predicted yield ranging between 2% and 7% were observed whereas very little deviations (1%–3%) from predicted yield were observed in blends with lignite indicating no significant interactions with corn stover. In addition, a single first-order reaction model using the Coats-Redfern approximation was utilized to predict the kinetic parameters of the pyrolysis reaction. The kinetic analysis indicated that each thermal evolution profile may be represented as a single first-order reaction. Three temperature regimes were identified for each of the coals while corn stover and the blends were analyzed using two and four temperature regimes, respectively.« less
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Characterizing thermogenic coalbed gas from Polish coals of different ranks by hydrous pyrolysis
Kotarba, M.J.; Lewan, M.D.
2004-01-01
To provide a better characterization of origin and volume of thermogenic gas generation from coals, hydrous pyrolysis experiments were conducted at 360??C for 72 h on Polish coals ranging in rank from lignite (0.3% R r) to semi-anthracite (2.0% Rr). Under these conditions, the lignites attained a medium-volatile bituminous rank (1.5% Rr), high-volatile bituminous coals attained a low-volatile bituminous rank (1.7% Rr), and the semi-anthracite obtained an anthracite rank (4.0% R r). Hydrous pyrolysis of a coal, irrespective of rank, provides a diagnostic ??13C value for its thermogenic hydrocarbon gases. This value can be used quantitatively to interpret mixing of indigenous thermogenic gas with microbial methane or exogenous thermogenic gas from other sources. Thermogenic methane quantities range from 20 dm3/kg of lignite (0.3% Rr) to 0.35 dm3/kg of semi-anthracite (2.0% Rr). At a vitrinite reflectance of 1.7% Rr, approximately 75% of the maximum potential for a coal to generate thermogenic methane has been expended. At a vitrinite reflectance of 1.7% Rr, more than 90% of the maximum potential for a coal to generate CO2 has been expended. Assuming that these quantities of generated CO2 remain associated with a sourcing coal bed as uplift or erosion provide conditions conducive for microbial methanogenesis, the resulting quantities of microbial methane generated by complete CO2 reduction can exceed the quantities of thermogenic methane generated from the same coal bed by a factor of 2-5. ?? 2004 Elsevier Ltd. All rights reserved.
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Regulation of coal polymer degradation by fungi. Tenth Quartery report, October 1996--December 1996
DOE Office of Scientific and Technical Information (OSTI.GOV)
Irvine, R.L.; Bumpus, J.A.
1997-01-28
It has long been known that low rank coal such as leonardite can be solubilized by strong base (>pH 12). Recent discoveries have also shown that leonardite is solubilized by Lewis bases at considerably lower pH values and by fungi that secrete certain Lewis bases (i.e., oxalate ion). During the current reporting period we have studied the ability of a strong base (sodium hydroxide, pH 12), and two fungi, Phanerochaete chrysosporium and Trametes versicolor, to solubilize Argonne Premium Coals. In general, Argonne Premium Coals were relatively resistant to base mediated solubilization. However, when these coals were preoxidized (150{degrees}C for sevenmore » days), substantial amounts of several coals were solubilized. Most affected were the Lewiston-Stockton bituminous coal, the Beulah-Zap lignite, the Wyodak-Anderson subbituminous coal and the Blind Canyon bituminous coal. Argonne Premium Coals were previously shown by us to be relatively resistant to solubilization by sodium oxalate. When preoxidized coals were treated with sodium oxalate, only the Beulah-Zap lignite was substantially solubilized. Although very small amounts of the other preoxidized coals were solubilized by treatment with oxalate, the small amount of solubilization that did take place was generally increased relative to that observed for coals that were not preoxidized. None of the Argonne Premium Coals were solubilized by P. chrysosporium or T. versicolor. Of considerable interest, however, is the observation that P. chrysosporium and T. versicolor mediated extensive solubilization of Lewiston-Stockton bituminous coal, the Beulah-Zap lignite and the Wyodak-Anderson subbituminous coal.« less
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Utilization of lignite power generation residues for the production of lightweight aggregates.
Anagnostopoulos, Iason M; Stivanakis, Victor E
2009-04-15
A novel process is proposed for the utilization of lignite combustion solid residues in the production of inflammable lightweight aggregates (LWA). The process consists of two stages, pelletization and sintering, and carbon contained in BA was used as the process fuel. The main residues bottom ash (BA) and fly ash (FA) from Megalopolis power plant were characterized, mixed in different proportions and treated through pelletization and sintering process. Sintering benefits from combustion of BA carbon content and the product is a hardened porous cake. The energy required for achievement of high temperatures, in the range of 1250 degrees C, was offered by carbon combustion and CO(2) evolution is responsible for porous structure formation. Selected physical properties of sintered material relevant to use as lightweight aggregates were determined, including bulk density, porosity and water absorption. Bulk density varies from 0.83 to 0.91 g/cm(3), porosity varies from 60% to 64% and water absorption varies from 66% to 80%. LWA formed is used for the production of lightweight aggregate concrete (LWAC). Thermal conductivity coefficient varies from 0.25 to 0.37 W/mK (lower than maximum limit 0.43 W/mK) and compressive strength varies from 19 to 23 MPa (higher than minimum limit 17 MPa). The results indicate that sintering of lignite combustion residues is an efficient method of utilization of carbon containing BA and production of LWA for structural and insulating purposes. Carbon content of BA is a key factor in LWA production. Finally, this research work comprises the first proposed application for utilization of BA in Greece.
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Pipeline transportation of upgraded Yugoslavian lignite fuels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ljubicic, B.; Anderson, C.; Bukurov, Z.
1993-12-31
Hydraulic transport and handling procedures for coal are not widely used, but when practiced, they result in a technically and economically successful operation. Potentially the most attractive way to utilize lignitic coals for power generation would be to combine hydraulic mining techniques with aqueous ash removal, hydrothermal processing, solids concentration, and coal-water fuel (CWF) combustion. Technical and economic assessment of this operation is being implemented within the Yugoslavian-American Scientific Technical Cooperation Agreement. The Energy and Environmental Research Center (EERC), Grand Forks, North Dakota, with support from the U.S. Department of Energy, has entered into a jointly sponsored research project withmore » Electric Power of Serbia (EPS), Belgrade, Yugoslavia, to investigate the application of the nonevaporative hydrothermal drying procedure, commonly called hot-water drying (HWD), developed at the EERC, to the lignite from the Kovin deposit. Advances in hydrothermal treatment of low-rank coals (LRCs) at the EERC have enabled cheaper, more reactive LRCs to be used in coal-water fuels (CWFs). HWD is a high-temperature, nonevaporative drying technique carried out at high pressure in water that permanently alters the structure of LRC. It solves the stability problems by producing a safe, easily transported, liquid fuel that can be handled and used like oil. For continued or increased success, it is necessary to evaluate carefully all aspects of slurry technology that permit further optimization. This paper discusses some aspects of low-rank coal hydraulic transport combined with hydrothermal treatment as an alternative energy solution toward less oil dependence in Yugoslavia.« less
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NASA Astrophysics Data System (ADS)
Singh, R. P.; Prasad, A. K.; Kafatos, M.
2005-12-01
The Indo-Gangetic (IG) basin is one of the largest basins in the world which is densely populated and suffers with dense fog, haze and smog during winter season. About 500 million people live in the IG basin and due to the dense fog, haze and smog day to day life suffers. India is the third largest producer of the coal in the world and a large share is used in power and industrial sector. The coal used in the power plants is of poor quality (mostly E-F grade or lignite) with high ash content (35-50%) and low calorific value. India's energy consumption has increased 208% from 4.16 quadrillion Btu (quads) in 1980 to 12.8 quads in 2001 with a coal share of ~50.9%. Recent studies using satellite (Moderate Resolution Imaging Spectroradiometer (MODIS) and Multiangle Imaging SpectroRadiometer (MISR)) and AERONET measurements show high aerosol optical depth (AOD) representing the intense air pollution over the IG basin that persists throughout the year. Such high concentrations of AOD show spatial and temporal variations which are controlled by the meteorological conditions (wind pattern, relative humidity, air temperature etc.) and topography. The high AOD observed over the IG basin is attributed to the emissions of fossil fuel SO2 and black carbon which has increased about 6 fold since 1930. The high AOD over the IG basin is attributed to the huge emission from the dense network of coal based thermal power plants in the IG basin and its surroundings that may be the probable cause for the atmospheric brown clouds (ABC). The impact of aerosol parameters on the climatic conditions will be discussed.
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Hatcher, P.G.; Lerch, H. E.; Verheyen, T.V.
1990-01-01
It is generally recognized that xylem from trees that are buried in peat swamps is transformed first to huminite macerals in brown coal and then to vitrinite macerals in bituminous coal by processes collectively known as coalification. In order to understand the chemical nature of coalification of xylem and the chemical structures that eventually evolve in coal, we examined a series of gymnospermous xylem samples coalified to varying degrees. The samples included modern fresh xylem, modern degraded xylem in peat, and xylem coalified to ranks of brown coal (lignite B), lignite A, and subbituminous coal. The organic geochemical methods used in this study included solid-state 13C nuclear magnetic resonance (NMR) and pyrolysis/gas chromatography/mass spectrometry. The NMR method provided average compositional information, and the pyrolysis provided detailed molecular information. Although the samples examined include different plants of different geologic ages, they all share a common feature in that they are gymnospermous and presumably have or had a similar kind of lignin. The data obtained in this study provide enough details to allow delineation of specific coalification pathway for the xylem is microbial degradation in peat (peatification), leading to selective removal of cellulosic components. These components constitute a large fraction of the total mass of xylem, usually greater than 50%. Although cellulosic components can survive degradation under certain conditions, their loss during microbial degradation is the rule rather than exception during peatification. As these components of xylem are degraded and lost, lignin, another major component of xylem, is selectively enriched because it is more resistant to microbial degradation than the cellulosic components. Thus, lignin survives peatification in a practically unaltered state and becomes the major precursor of coalified xylem. During its transformation to brown coal and lignite A, lignin in xylem is altered by two important processes. The first involves loss of methoxyl groups, primarily by demethylation (Fig. 1A). The end products of demethylation are catechol-like structures as shown below in Figure 1B. The second transformation process involves increased cross-linking of the aromatic rings. This cross-linking induces increased carbon substitution of the aromatic rings such that the lignin-derived structures become more highly condensed. During its conversion to coalified xylem in subbituminous coal, lignitic xylem, composed primarily of condensed catechol-like structures, is transformed to a macromolecular material primarily composed of phenol-like structures. The catechol-like structures of lignitic xylem loose a hydroxyl group, which is replaced by a hydrogen to form the phenol-like structure as shown in the example in Figure 1B. The pyrolysis data provided only a few clues as to the fate of the C3-side chain of lignin during coalification. However, the NMR data suggest that this side chain is altered, probably by loss of the hydroxyl groups that are attached in modern lignin. Interference in the NMR analysis by aliphatic components of wood, such as resins, precludes definitive determinations of the fate of the C3-side chain during coalification. ?? 1990.
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NASA Astrophysics Data System (ADS)
Weijers, J. W. H.; Steinmann, P.; Hopmans, E. C.; Basiliko, N.; Finkelstein, S. A.; Johnson, K. R.; Schouten, S.; Sinninghe Damsté, J. S.
2012-04-01
Branched glycerol dialkyl glycerol tetraether (brGDGT) membrane lipids occur ubiquitously in peat and soil. In soil, the degree of methylation and cyclisation of branched tetraethers (MBT index and CBT ratio, respectively) has shown to relate to both soil pH and annual mean air temperature (MAT). Using this relation, past annual MATs can be reconstructed by analysing brGDGTs in marine sediment records near large river outflows. More recently, the potential of this MBT/CBT proxy is also being explored in lakes. Despite being more abundant in peat than soils, however, the utility of the proxy has not yet been fully explored in peat records. Present day peat records generally extent back to the early Holocene, but if the MBT/CBT proxy were shown to be applicable in peat deposits, there is also potential to apply it to immature coal deposits like lignites, which could provide valuable snapshots of continental climate back to the early Cenozoic. Here results are presented of analyses of different peats in south eastern Canada, showing that the pH of peat along a nutrient gradient is rather well reflected by the CBT. Annual MAT reconstructions based on the MBT/CBT soil calibration, however, tend to overestimate measured MAT. This is also the case for peat analysed from the surface of Etang de la Gruère peat bog in the Swiss Jura Mountains. Along the 6m depth profile of this bog (~13ka), CBT-reconstructed pH is compared with in-situ measured pore water pH showing that the brGDGT composition does not reflect present-day in-situ conditions. Instead, it reflects a stratigraphic boundary between Carex and Sphagnum dominated peat at 4 m depth that is not present in the pore water profile, testifying to a 'fossil' nature of the brGDGTs down the peat bog. Analyses of three immature coals of the Argonne Premium Coal Series reveal that branched GDGTs are present in the most immature coal, the Beulah Zap lignite (Ro = 0.25%), and only just above detection limit in the Wyodak Anderson coal (Ro = 0.32%), both of about the same age (Late Palaeocene). In the more mature Illinois #6 coal (Ro = 0.46%), brGDGTs are completely absent. In the Denver Basin, a comparison is made between outcrop and drilled core samples of Palaeocene lignites. BrGDGTs are preserved in the core samples, although in low quantities compared to peat. Outcrop samples are clearly overprinted by modern soil derived brGDGTs, despite digging a meters deep trench, which shows the need to obtain fresh non-weathered samples by coring. Reconstructed annual MAT for both the Beulah Zap and the Denver Basin lignites are several degrees higher than estimates based on leaf margin and oxygen isotope analyses from the same sites. Both reconstructions do testify, nevertheless, to the warm continental conditions during the early Cenozoic of the central U.S.A.. Although further validation is required, potentially in the form of a specific peat calibration, these results do show potential for application of the MBT/CBT temperature proxy in peat and lignite deposits.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Hirschon, A.S.; Wilson, R.B.
We analyzed two sets of liquefaction experiments, one involved the liquefaction of Black Thunder Coal with the corresponding recycle vehicle, and the second set of liquefaction runs involved the liquefaction of Argonne North Dakota Lignite. We compared coal conversions of Black Thunder coal and recycle solvent using Fe(CO){sub 5} and carbon monoxide/hydrogen atmospheres and a MolyVanL molybdenum catalyst under a hydrogen atmosphere. We also continued our investigation of the effect of water on the conversions. We found that addition of water seemed to decrease the amount of oils; we determined the effect of water with the recycle solvent alone, (nomore » coal added) under similar conditions, and again produced a decrease in oil yields. FIMS analyses of the hexane and toluene soluble fractions seem to indicate that in the experiment when water was added, a considerable amount of light material remained behind in the toluene layer, suggesting that somehow the addition of water decreased the amount of extracted material, perhaps by increasing the amount of polarity of the product. When the conversion was conducted with the MolyVanL molybdenum catalyst a good quality product in terms of lower viscosity was produced; however, conversions to THF soluble material was not increased. We believe the molybdenum catalyst hydrogenated the recycle vehicle rather than effectively converted the coal. In order to eliminate the effect of solvent we have often conducted experiments in an inert solvent with Argonne coals. We conducted several coal conversions experiments using an Argonne North Dakota lignite. We compared several dispersed Fe catalysts and in addition, a nickel catalyst. We investigated nickel as a catalyst since we believe this metal may be more effective in decarboxylating low rank coals. Consistent with this premise we found that the nickel catalyst gave the highest conversions.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Daniel J. Stepan; Thomas A. Moe; Melanie D. Hetland
New federal drinking water regulations have been promulgated to restrict the levels of disinfection by-products (DBPs) in finished public water supplies. DBPs are suspected carcinogens and are formed when organic material is partially oxidized by disinfectants commonly used in the water treatment industry. Additional federal mandates are expected in the near future that will further affect public water suppliers with respect to DBPs. Powdered activated carbon (PAC) has traditionally been used by the water treatment industry for the removal of compounds contributing to taste and odor problems. PAC also has the potential to remove naturally occurring organic matter (NOM) frommore » raw waters prior to disinfection, thus controlling the formation of regulated DBPs. Many small water systems are currently using PAC for taste and odor control and have the potential to use PAC for controlling DBPs. This project, a cooperative effort between the Energy & Environmental Research Center (EERC), the Grand Forks Water Treatment Plant, and the University of North Dakota Department of Civil Engineering, consists of several interrelated tasks. The objective of the research was to evaluate a cost-effective PAC produced from North Dakota lignite for removing NOM from water and reducing trihalomethane formation potential. The research approach was to develop a statistically valid testing protocol that can be used to compare dose-response relationships between North Dakota lignite-derived PAC and commercially available PAC products. A statistical analysis was performed to determine whether significant correlations exist between operating conditions, water properties, PAC properties, and dose-response behavior. Pertinent physical and chemical properties were also measured for each of the waters and each of the PACs.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang, Lili; Schobert, Harold H.; Song, Chunshan
1998-01-01
The main objectives of this project were to study the effects of low-temperature pretreatments on coal structure and their impacts on subsequent liquefaction. The effects of pretreatment temperatures, catalyst type, coal rank, and influence of solvent were examined. Specific objectives were to identify the basic changes in coal structure induced by catalytic and thermal pretreatments, and to determine the reactivity of the catalytically and thermally treated coals for liquefaction. In the original project management plan it was indicated that six coals would be used for the study. These were to include two each of bituminous, subbituminous, and lignite rank. Formore » convenience in executing the experimental work, two parallel efforts were conducted. The first involved the two lignites and one subbituminous coal; and the second, the two bituminous coals and the remaining subbituminous coal. This Volume presents the results of the first portion of the work, studies on two lignites and one subbituminous coal. The remaining work accomplished under this project will be described and discussed in Volume 2 of this report. The objective of this portion of the project was to determine and compare the effects of solvents, catalysts and reaction conditions on coal liquefaction. Specifically, the improvements of reaction conversion, product distribution, as well as the structural changes in the coals and coal-derived products were examined. This study targeted at promoting hydrogenation of the coal-derived radicals, generated during thermal cleavage of chemical bonds, by using a good hydrogen donor-solvent and an effective catalyst. Attempts were also made in efforts to match the formation and hydrogenation of the free radicals and thus to prevent retrogressive reaction.« less
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EERC pilot-scale CFBC evaluation facility Project CFB test results. Topical report, Task 7.30
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mann, M.D.; Hajicek, D.R.; Henderson, A.K.
Project CFB was initiated at the University of North Dakota Energy and Environmental Research Center (EERC) in May 1988. Specific goals of the project were to (1) construct a circulating fluidized-bed combustor (CFBC) facility representative of the major boiler vendors` designs with the capability of producing scalable data, (2) develop a database for use in making future evaluations of CFBC technology, and (3) provide a facility for evaluating fuels, free of vendor bias for use in the - energy industry. Five coals were test-burned in the 1-MWth unit: North Dakota and Asian lignites, a Wyoming subbituminous, and Colorado and Pennsylvaniamore » bituminous coats. A total of 54 steady-state test periods were conducted, with the key test parameters being the average combustor temperature, excess air, superficial gas velocity, calcium-to-sulfur molar ratio, and the primary air-to-secondary air split. The capture for a coal fired in a CFBC is primarily dependent upon the total alkali-to-sulfur ratio. The required alkali-to ratio for 90% sulfur retention ranged from 1.4 to 4.9, depending upon coal type. While an alkali-to-ratio of 4.9 was required to meet 90% sulfur retention for the Salt Creek coal versus 1.4 for the Asian lignite, the total amount of sorbent addition required is much less for the Salt Creek coal, 4.2 pound sorbent per million Btu coal input, versus 62 pound/million Btu for the Asian lignite. The bituminous coals tested show optimal capture at combustor temperatures of approximately 1550{degree}F, with low-rank coals having optimal sulfur capture approximately 100{degree}F lower.« less
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EERC pilot-scale CFBC evaluation facility Project CFB test results
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mann, M.D.; Hajicek, D.R.; Henderson, A.K.
Project CFB was initiated at the University of North Dakota Energy and Environmental Research Center (EERC) in May 1988. Specific goals of the project were to (1) construct a circulating fluidized-bed combustor (CFBC) facility representative of the major boiler vendors' designs with the capability of producing scalable data, (2) develop a database for use in making future evaluations of CFBC technology, and (3) provide a facility for evaluating fuels, free of vendor bias for use in the - energy industry. Five coals were test-burned in the 1-MWth unit: North Dakota and Asian lignites, a Wyoming subbituminous, and Colorado and Pennsylvaniamore » bituminous coats. A total of 54 steady-state test periods were conducted, with the key test parameters being the average combustor temperature, excess air, superficial gas velocity, calcium-to-sulfur molar ratio, and the primary air-to-secondary air split. The capture for a coal fired in a CFBC is primarily dependent upon the total alkali-to-sulfur ratio. The required alkali-to ratio for 90% sulfur retention ranged from 1.4 to 4.9, depending upon coal type. While an alkali-to-ratio of 4.9 was required to meet 90% sulfur retention for the Salt Creek coal versus 1.4 for the Asian lignite, the total amount of sorbent addition required is much less for the Salt Creek coal, 4.2 pound sorbent per million Btu coal input, versus 62 pound/million Btu for the Asian lignite. The bituminous coals tested show optimal capture at combustor temperatures of approximately 1550[degree]F, with low-rank coals having optimal sulfur capture approximately 100[degree]F lower.« less
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Hatcher, P.G.; Breger, I.A.; Szeverenyi, N.; Maciel, G.E.
1982-01-01
Coalified logs ranging in age from Late Pennsylvania to Miocene and in rank from lignite B to bituminous coal were analyzed by 13C nuclear magnetic resonance (NMR) utilizing the cross-polarization, magic-angle spinning technique, as well as by infrared spectroscopy. The results of this study indicate that at least three major stages of coalification can be observed as wood gradually undergoes transformation to bituminous coal. The first stage involves hydrolysis and loss of cellulose from wood with retention and differential concentration of the resistant lignin. The second stage involves conversion of the lignin residues directly to coalified wood of lignitic rank, during which the oxygen content of intermediate diagenetic products remains constant as the hydrogen content and the carbon content increases. These changes are thought to involve loss of methoxyl groups, water, and C3 side chains from the lignin. In the third major stage of coalification, the coalified wood increases in rank to subbituminous and bituminous coal; during this stage the oxygen content decreases, hydrogen remains constant, and the carbon content increases. These changes are thought to result from loss of soluble humic acids that are rich in oxygen and that are mobilized during compaction and dewatering. Relatively resistant resinous substances are differentially concentrated in the coal during this stage. The hypothesis that humic acids are formed as mobile by-products of the coalification of lignin and function only as vehicles for removal of oxygen represents a dramatic departure from commonly accepted views that they are relatively low-molecular-weight intermediates formed during the degradation of lignin that then condense to form high-molecular-weight coal structures. ?? 1982.
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NASA Astrophysics Data System (ADS)
Manousakas, M.; Diapouli, E.; Papaefthymiou, H.; Migliori, A.; Karydas, A. G.; Padilla-Alvarez, R.; Bogovac, M.; Kaiser, R. B.; Jaksic, M.; Bogdanovic-Radovic, I.; Eleftheriadis, K.
2015-04-01
Particulate matter (PM) is an important constituent of atmospheric pollution especially in areas under the influence of industrial emissions. Megalopolis is a small city of 10,000 inhabitants located in central Peloponnese in close proximity to three coal opencast mines and two lignite fired power plants. 50 PM10 samples were collected in Megalopolis during the years 2009-11 for elemental and multivariate analysis. For the elemental analysis PIXE was used as one of the most effective techniques in APM analytical characterization. Altogether, the concentrations of 22 elements (Z = 11-33), whereas Black Carbon was also determined for each sample using a reflectometer. Factorization software was used (EPA PMF 3.0) for source apportionment analysis. The analysis revealed that major emission sources were soil dust 33% (7.94 ± 0.27 μg/m3), biomass burning 19% (4.43 ± 0.27 μg/m3), road dust 15% (3.63 ± 0.37 μg/m3), power plant emissions 13% (3.01 ± 0.44 μg/m3), traffic 12% (2.82 ± 0.37 μg/m3), and sea spray 8% (1.99 ± 0.41 μg/m3). Wind trajectories have suggested that metals associated with emission from the power plants came mainly from west and were connected with the locations of the lignite mines located in this area. Soil resuspension, road dust and power plant emissions increased during the warm season of the year, while traffic/secondary, sea spray and biomass burning become dominant during the cold season.
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Integrated stratigraphy of Paleocene lignite seams of the fluvial Tullock Formation, Montana (USA).
NASA Astrophysics Data System (ADS)
Noorbergen, Lars J.; Kuiper, Klaudia F.; Hilgen, Frederik J.; Krijgsman, Wout; Dekkers, Mark J.; Smit, Jan; Abels, Hemmo A.
2015-04-01
Coal-bearing fluvial sedimentation is generally thought to be dominated by autogenic processes that are processes intrinsic to the sedimentary system. Ongoing research however suggests that several fluvial processes such as floodplain inundation and avulsion, can also be controlled by external forcing such as orbital climate change. Still, the exact role of orbital climate forcing in fluvial sediments is difficult to decipher since riverine deposits are complicated by variable sedimentation rates including erosion of previously deposited material, by lateral heterogeneity of sedimentation, and by scarcity of independent dating methods. The early Paleocene lignite-bearing Tullock Formation of the Williston Basin in eastern Montana represents a record of fluvial sedimentation that is perfectly exposed and, displays a seemingly regular alternation of sandstones and lignite seams. These coal beds contain multiple volcanic ash layers. Here, we use an integrated stratigraphic approach (litho- and magnetostratigraphy, geochemical fingerprinting and radio-isotope dating of volcanic ash layers) to establish a high-resolution time frame for the early Paleocene fluvial sediments. First age estimations indicate that the Tullock Formation in Eastern Montana was deposited over a time span of ~ 1000 kyr subsequent to the Cretaceous - Paleogene boundary, dated at ~ 65.95 Ma [1]. Initial high-resolution magnetostratigraphy revealed the occurrence of the C29r/C29n polarity reversal which was stratigraphic consistent at different field locations. We investigate the regional significance of sedimentary change at multiple sites of the same age in order to provide improved insight on the role of orbital forcing in fluvial coal formation. References: [1] Kuiper, K.F., Deino, A., Hilgen, F.J., Krijgsman, W., Renne, P.R., Wijbrans, J.R. (2008). Synchronizing Rock Clocks of Earth History. Science 320, 500-504.
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NASA Astrophysics Data System (ADS)
Seserman, Diana-Maria; Veste, Maik; Freese, Dirk
2017-04-01
The profitability of reclaiming post-mining areas depends on the tree biomass productivity and the restoration of ecosystem functions, such as improving soil and water quality. Agroforestry systems, regarded as combined land-use systems of trees and crops, have the ability to facilitate soil development while reducing wind speed, soil erosion and evaporation. Achieving the maximum biomass productivity of the tree stands depends on the corresponding soil conditions and water availability, but is also influenced by stand structure and the competition between individual trees. For this purpose, black locust (Robinia pseudoacacia L.) trees were planted in a Nelder design in 2010, on a reclaimed post-mining site of the open-cast lignite mining in Welzow Süd (Brandenburg, Germany). Black locust is regarded as a drought-adapted tree species and commonly used for the reclamation of former lignite mining sites in Lower Lusatia, Germany. The Nelder design encompasses angles of arc of equal measure and with the same origin traversed by successive circumferences set at a predefined radial distance. Accordingly, a total of 1071 trees were planted in Welzow Süd at the intersection between 63 spokes and 17 circumferences and at densities ranging from 0.4 to 8.0 m2, with the aim of examining the influence of stand density on the tree growth in a timeframe of six years. In order to evaluate the biomass production of the trees and to determine an optimal planting density on a marginal land, various scenarios were assessed with the help of the Yield-SAFE model, a parameter-sparse process-based agroforestry model. The study revealed the consequences of choosing different tree densities on the tree biomass productivity and water use of trees in relation to the competition for light and water. References Keesman KJ, van der Werf W, van Keulen H, 2007. Production ecology of agroforestry systems: A minimal mechanistic model and analytical derivation of the land equivalent ratio. Mathematical Biosciences, vol. 209, pp. 608-623. Mantovani D, Veste M, Böhm C, Vignudelli M, Freese D, 2015. Drought impact on the spatial and temporal variation of growth performance and plant water status of black locust (Robinia pseudoacacia L.) in agroforestry systems in Lower Lusatia (Germany). iForest 8, 743-757. Mantovani D, Veste M, Freese D, 2014. Black locust (Robinia pseudoacacia L.) ecophysiological and morphological adaptations to drought and their consequence on biomass production and water use efficiency. New Zealand Journal of Forestry 44, 29. van der Werf W, Keesman K, Burgess PJ, Graves AR, Pilbeam D, Incoll LD, Metselaar K, Mayus M, Stappers R, van Keulen H, Palma JHN, Dupraz C, 2007. Yield-SAFE: a parameter-sparse process-based dynamic model for predicting resource capture, growth and production in agroforestry systems. Ecological Engineering, vol. 29, pp. 419-433.
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Cowdery, Timothy K.
1997-01-01
Land-use factors that increased nitrate and herbicide concentrations were greater tilled area, chemical application, irrigation, and cropland contiguity. Hydrogeological factors that increased these concentrations were a deeper watertable (higher oxygen concentration and less organic carbon), larger grain-size and degree of sorting of aquifer material (shorter time in the soil zone and aquifer), and fewer sulfur-containing minerals (lignite and pyrite) composing the aquifer. High rainfall, just before sampling of the Sheyenne Delta aquifer, contributed to the relatively low nitrate and pesticide concentrations in the shallow ground water of this aquifer by raising the water table higher into the soil zone, increasing ponded water (increasing biodegradation), preventing some chemical application (flooded fields), and leaching and then displacing nitrate-rich water downward, beneath new recharge. The shallow ground-water quality measured beneath cropland in these land-use study areas covers a large range. The land-use, hydrogeological, and rainfall factors controlling this quality also control shallow ground-water quality in other surficial aquifers in the Red River of the North Basin. Although not used for drinking water, 43% of the shallow ground water from the Otter Tail outwash aquifer was above the U.S. Environmental Protection Agency's nitrate maximum contaminant level of 10 mg/L-N, reducing its potential uses. These high nitrate concentrations do not threaten the Otter Tail outwash aquifer's surface-water bodies with eutrophication however, because significant denitrification occurs beneath riparian wetlands before ground water discharges to surface waters.
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2001-08-01
This simulated natural color ASTER image in the German state of North Rhine Westphalia covers an area of 30 by 36 km, and was acquired on August 26, 2000. On the right side of the image are 3 enormous opencast coalmines. The Hambach opencast coal mine has recently been brought to full output capacity through the addition of the No. 293 giant bucket wheel excavator. This is the largest machine in the world; it is twice as long as a soccer field and as tall as a building with 30 floors. To uncover the 2.4 billion tons of brown coal (lignite) found at Hambach, five years were required to remove a 200-m-thick layer of waste sand and to redeposit it off site. The mine currently yields 30 million tons of lignite annually, with annual capacity scheduled to increase to 40 million tons in coming years. The image is centered at 51 degrees north latitude, 6.4 degrees east longitude. http://photojournal.jpl.nasa.gov/catalog/PIA02676
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NASA Astrophysics Data System (ADS)
Greene, M. I.; Ladelfa, C. J.; Bivacca, S. J.
1980-05-01
Flash hydropyrolysis (FHP) of coal is an emerging technology for the direct production of methane, ethane and BTX in a single-stage, high throughput reactor. The FHP technique involves the short residence time (1-2 seconds), rapid heatup of coal in a dilute-phase, transport reactor. When integrated into an overall, grass-roots conversion complex, the FHP technique can be utilized to generate a product consisting of SNG, ethylene/propylene, benzene and Fischer-Tropsch-based alcohols. This paper summarizes the process engineering and economics of conceptualized facility based on an FHP reactor operation with a lignitic coal. The plant is hypothetically sited near the extensive lignite fields located in the Texas region of the United States. Utilizing utility-financing methods for the costing of SNG, and selling the chemicals cogenerated at petrochemical market prices, the 20-year average SNG cost has been computed to vary between $3-4/MM Btu, depending upon the coal costs, interest rates, debt/equity ratio, coproduct chemicals prices, etc.
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Hashim, Rohasliney; Jackson, Donald C
2009-01-01
A three-year study (July 2000 – June 2003) of fish assemblages was conducted in four tributaries of the Big Black River: Big Bywy, Little Bywy, Middle Bywy and McCurtain creeks that cross the Natchez Trace Parkway, Choctaw County, Mississippi, USA. Little Bywy and Middle Bywy creeks were within watersheds influenced by the lignite mining. Big Bywy and Middle Bywy creeks were historically impacted by channelisation. McCurtain Creek was chosen as a reference (control) stream. Fish were collected using a portable backpack electrofishing unit (Smith-Root Inc., Washington, USA). Insectivorous fish dominated all of the streams. There were no pronounced differences in relative abundances of fishes among the streams (P > 0.05) but fish assemblages fluctuated seasonally. Although there were some differences among streams with regard to individual species, channelisation and lignite mining had no discernable adverse effects on functional components of fish assemblages suggesting that fishes in these systems are euryceous fluvial generalist species adapted to the variable environments of small stream ecosystems. PMID:24575177
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Enhanced phenol removal in an innovative lignite activated coke-assisted biological process.
Zhang, Chen; Li, Jianfeng; Cheng, Fangqin; Liu, Yu
2018-07-01
In this study, a lignite activated coke (LAC)-assisted activated sludge (AS) process was developed for enhancing biodegradation of phenol, while the effects of LAC on sludge properties and microbial community structure were investigated. It was found that more than 90% of phenol was removed within 1 h in the LAC/AS, which was 3 times higher than the conventional AS process. Moreover, the floc size and settleability were also significantly improved in the LAC/AS. These results suggested that LAC could serve as the nucleating agent to promote the formation of compact floc, which was beneficial for toxicity mitigation and system stability. The microbial community analysis by 16S high-throughput pyrosequencing technology further revealed a more abundant bacterial richness and diversity in the LAC/AS process loaded with phenol, while some phenol degraders, such as Propionibacteriaceae were enriched. Engineering implications further suggests the LAC-assisted AS process is technically sound and economically viable. Copyright © 2018 Elsevier Ltd. All rights reserved.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Emine Yagmur; Taner Togrul
2005-12-01
The effects of microwave receptors to coal (receptor/coal) ratio and the period of heating by microwave energy on the solubilization of Turkish coals (Tuncbilek, Mugla-Yatagan, Beypazari lignites, and Zonguldak bituminous coal) in tetralin have been investigated. V{sub 2}O{sub 5} and TiO{sub 2} were used as microwave receptors. The changes of liquid product yield indicated that it depended significantly on the type and amount of receptor and the type of coal. A significant increase in the lignite conversions to oil fractions was observed by the addition of the V{sub 2}O{sub 5} receptor. The use of TiO{sub 2} receptor decreased the yieldmore » of THF soluble coal products. However, both V{sub 2}O{sub 5} and TiO{sub 2} receptors decreased the yield of preasphaltene (PAS) and asphaltene (AS) due to their catalytic effect on the coal liquefaction. 15 refs., 9 figs., 1 tab.« less
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Microbial methane formation in deep aquifers of a coal-bearing sedimentary basin, Germany
Gründger, Friederike; Jiménez, Núria; Thielemann, Thomas; Straaten, Nontje; Lüders, Tillmann; Richnow, Hans-Hermann; Krüger, Martin
2015-01-01
Coal-bearing sediments are major reservoirs of organic matter potentially available for methanogenic subsurface microbial communities. In this study the specific microbial community inside lignite-bearing sedimentary basin in Germany and its contribution to methanogenic hydrocarbon degradation processes was investigated. The stable isotope signature of methane measured in groundwater and coal-rich sediment samples indicated methanogenic activity. Analysis of 16S rRNA gene sequences showed the presence of methanogenic Archaea, predominantly belonging to the orders Methanosarcinales and Methanomicrobiales, capable of acetoclastic or hydrogenotrophic methanogenesis. Furthermore, we identified fermenting, sulfate-, nitrate-, and metal-reducing, or acetogenic Bacteria clustering within the phyla Proteobacteria, complemented by members of the classes Actinobacteria, and Clostridia. The indigenous microbial communities found in the groundwater as well as in the coal-rich sediments are able to degrade coal-derived organic components and to produce methane as the final product. Lignite-bearing sediments may be an important nutrient and energy source influencing larger compartments via groundwater transport. PMID:25852663
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Coal char oxidation kinetics in air medium
NASA Astrophysics Data System (ADS)
Slyusarskiy, K. V.; Jankovskiy, S. A.; Korotkikh, A. G.; Sorokin, I. V.
2017-01-01
Research on oxidation in air medium process of three different coal chars with various carbon content was presented. The anthracite, T-grade bituminous coal and 2B-grade lignite char powders with particle size less than 80 µm were studied. The coal char oxidation was studied by isothermal method using coupled TG-DSC analyzer Netzsch STA 449 Jupiter F3 in the temperature range 1000-1200 °C. Experiments were carried out at ambient pressure. Volumetric flow rate of oxidation medium into analyzer chamber was 250 ml/min and consisted of oxygen and argon with volumetric ratio 24:1. Based on experimental data, the average rate of carbon oxidation reaction values were defined at each temperature. Kinetic constants (frequency factor and activation energy) of reaction were defined as well via 1st order Arrhenius equation. Activation energy values are in good agreement with the data presented in the literature. Activation energy values for anthracite char are 1.6-1.7 times higher than those for bituminous coal and lignite chars, respectively.
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Leaching and toxicity behavior of coal-biomass waste cocombustion ashes.
Skodras, G; Prokopidou, M; Sakellaropoulos, G P
2006-08-01
Land disposal of ash residues, obtained from the cocombustion of Greek lignite with biomass wastes, is known to create problems due to the harmful constituents present. In this regard, the leachability of trace elements from lignite, biomass, and blends cocombustion ashes was investigated by using the Toxicity Characteristic Leaching Procedure (TCLP) of the US Environmental Protection Agency (US EPA). In this work, the toxicity of the aqueous leachates and the concentrations of the metals obtained from the leaching procedure were measured using the Microtox test (Vibrio fischeri) and inductive coupled plasma-atomic emission spectrometer (ICP-AES), respectively. The toxic effects of most leachates on Vibrio fischeri were found to be significantly low in both 45% and 82% screening test protocols. However, the liquid sample originating from olive kernels fly ash (FA4) caused the highest toxic effect in both protocols, which can be attributed to its relatively high concentrations of As, Cd, Co, Cu, Mn, Ni, and Zn. Copyright 2006 Wiley Periodicals, Inc.
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Yang, Xiao; Yuan, Chengyong; Xu, Jiao; Zhang, Weijiang
2015-03-01
Lignite and sewage sludge were co-pyrolyzed in a vacuum reactor with high temperature (900°C) and long contact time (more than 2h). Beneficial synergetic effect on gas yield was clearly observed. Gas yield of blend fuel was evidently higher than that of both parent fuels. The gas volume yield, gas lower heating value (LHV), fixed carbon conversion and H2/CO ratio were 1.42 Nm(3)/kg(blend fuel), 10.57 MJ/Nm(3), 96.64% and 0.88% respectively, which indicated this new method a feasible one for gas production. It was possible that sewage sludge acted as gasification agents (CO2 and H2O) and catalyst (alkali and alkaline earth metals) provider during co-pyrolysis, promoting CO2-char and H2O-char gasification which, as a result, invited the improvement of gas volume yield, gas lower heating value and fixed carbon conversion. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Review of non-traditional coal mining countries. Part I
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pettigrew, J.
1976-03-01
The coal reserves and coal production of countries in Africa and Central and South America are reviewed. About 0.5 percent of world hard coal output originates from Central and South America, but production of lignite and brown coals is negligible. Colombia, Mexico and Brazil are the largest producers, while significant amounts of coal are won in Chile. At present Argentina, Peru and Venezuela have very small coal industries. Excluding the Republic of South Africa, the African continent has only about 0.25 percent of world coal reserves. Lignite and brown coal resources are negligible. Despite the relatively small amount of coalmore » resources there is nevertheless a degree of underexploitation. Of those African countries that have reserves, most are capable of modest increases in production given the right financial and technical assistance. Africa produces about 3.0 percent of total world coal production, and all but 0.2 percent comes from South Africa. Over half of the remainder is mined in Rhodesia.« less
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Chemical vapor deposition: Stable carbons from low-rank coals
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sharma, R.K.; Kulas, R.W.; Olson, E.S.
1996-12-31
A chemical vapor deposition (CVD) technique has been used to increase the oxidative stability of activated carbons. Activated carbons prepared from Gascoyne lignite (North Dakota) by thermal or potassium hydroxide activations were subjected to BCI, in helium at 727{degrees}C with or without benzene for a limited period of time, followed by annealing in helium at 900{degrees}C for three days. Untreated and acid-washed coal samples were used to assess the magnitude of the effect of mineral matter in the coal on the boron coating. The oxidative stability of the boron-modified carbons was determined from the decomposition curves obtained from the thermogravimetricmore » analysis. Modification of the as-received, KOH-treated carbon yielded oxidatively stable carbons up to an initial temperature of 520{degrees}C, compared to about 350{degrees}C for the starting material. Similar results were obtained for the carbonized Gascoyne lignite. Sulfurous acid washing of the Gascoyne significantly enhanced the thermal stability (600{degrees}C) of the boron-modified carbon.« less
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Air protection strategy in Poland
DOE Office of Scientific and Technical Information (OSTI.GOV)
Blaszczyk, B.
Air quality is one of the basic factors determining the environmental quality and influencing the life conditions of people. There is a shortage of proper quality air in many regions of Poland. In consequence, and due to unhindered transport, air pollution is the direct cause of losses in the national economy (reduction of crops, losses in forestry, corrosion of buildings and constructions, worsening of people`s health). Poland is believed to be one of the most contaminated European countries. The reason for this, primarily, is the pollution concomitant with energy-generating fuel combustion; in our case it means the use of solidmore » fuels: hard coal and lignite. This monocultural economy of energy generation is accompanied by low efficiency of energy use (high rates of energy loss from buildings, heat transmission pipelines, energy-consuming industrial processes). This inefficiency results in the unnecessary production of energy and pollution. Among other reasons, this results from the fact that in the past Poland did not sign any international agreements concerning the reduction of the emission of pollution. The activities aimes at air protection in Poland are conducted based on the Environmental Formation and Protection Act in effect since 1980 (with many further amendments) and the The Ecological Policy of the state (1991). The goals of the Polish air pollution reduction program for the period 1994-2000 are presented.« less
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43 CFR 8224.0-5 - Definitions.
Code of Federal Regulations, 2011 CFR
2011-10-01
..., DEPARTMENT OF THE INTERIOR RECREATION PROGRAMS PROCEDURES Fossil Forest Research Natural Area § 8224.0-5... Land Management designated to perform the duties described in this subpart: (b) Fossil means the..., bitumen, lignite, asphaltum and tar sands, even though they are of biologic origin: (c) Fossil Forest or...
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43 CFR 8224.0-5 - Definitions.
Code of Federal Regulations, 2012 CFR
2012-10-01
..., DEPARTMENT OF THE INTERIOR RECREATION PROGRAMS PROCEDURES Fossil Forest Research Natural Area § 8224.0-5... Land Management designated to perform the duties described in this subpart: (b) Fossil means the..., bitumen, lignite, asphaltum and tar sands, even though they are of biologic origin: (c) Fossil Forest or...
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43 CFR 8224.0-5 - Definitions.
Code of Federal Regulations, 2013 CFR
2013-10-01
..., DEPARTMENT OF THE INTERIOR RECREATION PROGRAMS PROCEDURES Fossil Forest Research Natural Area § 8224.0-5... Land Management designated to perform the duties described in this subpart: (b) Fossil means the..., bitumen, lignite, asphaltum and tar sands, even though they are of biologic origin: (c) Fossil Forest or...
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43 CFR 8224.0-5 - Definitions.
Code of Federal Regulations, 2014 CFR
2014-10-01
..., DEPARTMENT OF THE INTERIOR RECREATION PROGRAMS PROCEDURES Fossil Forest Research Natural Area § 8224.0-5... Land Management designated to perform the duties described in this subpart: (b) Fossil means the..., bitumen, lignite, asphaltum and tar sands, even though they are of biologic origin: (c) Fossil Forest or...
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Code of Federal Regulations, 2011 CFR
2011-07-01
... is located. (g) MRE instrument means the gravimetric dust sampler with a four channel horizontal... in the earth by any means or method, and the work of preparing the coal so extracted, including... bituminous coal, lignite, or anthracite from its natural deposits underground by any means or method, and the...
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Characterization of Coals and Lignites by Thermo-Magneto-Gravimetric Analysis.
ERIC Educational Resources Information Center
Rowe, M. W.
1983-01-01
Describes an inexpensive means for determining proximate analysis of coal, and by use of this data, its energy content. Pyrite content is also obtained by utilizing magnetic properties of iron. The simple device used makes the experiment suitable for the undergraduate laboratory. (Author/JN)
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Armstrong, C.A.
1984-01-01
The investigation of the water resources of the Dickinson lignite area, an area of about 500 square miles, was undertaken to define the hydrologic system of the area and to project probable effects of coal mining on the system.Aquifers occur in sandstone beds in: the Fox Hills Sandstone and the lower Hell Creek Formation of Cretaceous age, the upper Hell Creek Formation of Cretaceous age and the lower Ludlow Member of the Fort Union Formation of Tertiary age, and the upper Ludlow and lower Tongue River Members of the Fort Union Formation of Tertiary age. Aquifers also occur in the sandstone and lignite lenses in the upper Tongue River Member and the Sentinel Butte Member of the Fort Union Formation. Depths to the Fox Hills-lower Hell Creek aquifer system range from about 1,300 to 1,710 feet. Well yields range from 18 to 100 gallons per minute. The water is soft and is a sodium bicarbonate type. Dissolvedsolids concentrations in samples collected from the aquifer system ranged from 1,230 to 1,690 milligrams per liter.Depths to the upper Hell Creek-lower Ludlow aquifer system range from about 720 to 1,040 feet. Well yields generally are less than 30 gallons per minute but may be as much as 150 gallons per minute. The water is soft and a sodium bicarbonate type. Dissolved-solids concentrations in samples collected from the aquifer system ranged from 1,010 to 1,450 milligrams per liter.Depths to the upper Ludlow-lower Tongue River aquifer system range from about 440 to 713 feet. Well yields may range from about 1 to 100 gallons per minute. The water generally is soft and a sodium bicarbonate type but may be moderately hard and a sulfate type in the southwestern part of the area. Dissolved-solids concentrations in samples collected from the aquifer system ranged from 995 to 1,990 milligrams per liter. Depths to the upper Tongue River-Sentinel Butte aquifer system range from near land surface to about 530 feet below land surface. Well yields generally range from about 1 to 185 gallons per minute. Yields from the lignite parts of the system range from about 2 to 60 gallons per minute. The water generally is a sodium bicarbonate type, but locally sulfate is the dominant anion. Dissolved-solids concentrations in samples collected from the aquifer system generally ranged from 574 to 2,720 milligrams per liter.
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Altered transport of lindane caused by the retention of natural particles in saturated porous media
NASA Astrophysics Data System (ADS)
Ngueleu, Stéphane K.; Grathwohl, Peter; Cirpka, Olaf A.
2014-07-01
Attachment and straining of colloidal particles in porous media result in their reversible and irreversible retention. The retained particles may either increase the retention of hydrophobic pollutants by sorption onto the particles, or enhance pollutant transport when particles, loaded with the pollutants, are remobilized. The present study examines the effects of retained particles on the transport of the hydrophobic pesticide lindane (gamma-hexachlorocyclohexane) in saturated porous media. The lignite particles used have median diameters of about 3 μm, 1 μm, 0.8 μm, and 0.2 μm, respectively. Laboratory column experiments were analyzed by numerical modeling in order to identify and understand the processes involved in the transport of the particles and of lindane. Four scenarios were considered in which the solution containing lindane is injected either during or after the elution of the particles. The results show that lignite particles retained in a sandy porous medium alter the transport of the invading lindane. Particle retention was high in all scenarios and increased with increasing particle size. Remobilization of particles occurred due to a change in solution chemistry, and continuous particle detachment was observed over time. Numerical modeling of particle transport suggests that both reversible attachment and irreversible straining affected the transport of the particles. Lindane was retarded in all scenarios due to the strong particle retention in conjunction with the sorption of lindane onto the sand and onto retained particles, and the limited number of mobile particles carrying lindane. Moreover, it was found that intra-particle diffusion limited adsorption/desorption of lindane onto/from both limestone fragments of the sand and lignite particles. We assume that retention of lindane is reversible even though lindane recovery was incomplete over the duration of the experiments. The analysis of the effluent concentration suggests that retained particles loaded with lindane may become a secondary source of lindane. Models describing the transport of lindane fitted the experimental data very well and indicated the specific contribution of retained particles to the retardation of lindane. Since the properties of lignite also known as brown coal are similar to those of biochar, the results of the present study could be extended to the potential effects of biochar on lindane and other contaminants in soils, which would include both their retention and their enhanced transport. However, while the transport mechanisms of lindane are similar in water-unsaturated soils and saturated porous media considered here, the behavior of particles is more complex, requiring additional studies.
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Altered transport of lindane caused by the retention of natural particles in saturated porous media.
Ngueleu, Stéphane K; Grathwohl, Peter; Cirpka, Olaf A
2014-07-01
Attachment and straining of colloidal particles in porous media result in their reversible and irreversible retention. The retained particles may either increase the retention of hydrophobic pollutants by sorption onto the particles, or enhance pollutant transport when particles, loaded with the pollutants, are remobilized. The present study examines the effects of retained particles on the transport of the hydrophobic pesticide lindane (gamma-hexachlorocyclohexane) in saturated porous media. The lignite particles used have median diameters of about 3 μm, 1 μm, 0.8 μm, and 0.2 μm, respectively. Laboratory column experiments were analyzed by numerical modeling in order to identify and understand the processes involved in the transport of the particles and of lindane. Four scenarios were considered in which the solution containing lindane is injected either during or after the elution of the particles. The results show that lignite particles retained in a sandy porous medium alter the transport of the invading lindane. Particle retention was high in all scenarios and increased with increasing particle size. Remobilization of particles occurred due to a change in solution chemistry, and continuous particle detachment was observed over time. Numerical modeling of particle transport suggests that both reversible attachment and irreversible straining affected the transport of the particles. Lindane was retarded in all scenarios due to the strong particle retention in conjunction with the sorption of lindane onto the sand and onto retained particles, and the limited number of mobile particles carrying lindane. Moreover, it was found that intra-particle diffusion limited adsorption/desorption of lindane onto/from both limestone fragments of the sand and lignite particles. We assume that retention of lindane is reversible even though lindane recovery was incomplete over the duration of the experiments. The analysis of the effluent concentration suggests that retained particles loaded with lindane may become a secondary source of lindane. Models describing the transport of lindane fitted the experimental data very well and indicated the specific contribution of retained particles to the retardation of lindane. Since the properties of lignite also known as brown coal are similar to those of biochar, the results of the present study could be extended to the potential effects of biochar on lindane and other contaminants in soils, which would include both their retention and their enhanced transport. However, while the transport mechanisms of lindane are similar in water-unsaturated soils and saturated porous media considered here, the behavior of particles is more complex, requiring additional studies. Copyright © 2014 Elsevier B.V. All rights reserved.
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Sichletidis, L; Tsiotsios, I; Chloros, D; Daskalopoulou, E; Ziomas, I; Michailidis, K; Kottakis, I; Konstantinidis, T H; Palladas, P
2004-01-01
It is not known whether working in surface lignite mines can cause x-ray lesions or disorders of respiratory function. The aim of the study was to investigate the diachronic impact of environmental pollution on the respiratory system of lignite miners at mines in Eordea, Greece. Cases of 199 workers (Group A) residing permanently in the Eordea valley and 151 (Group B) living outside the Eordea valley were studied during Phase I and then re-examined after three years (Phase II). These cases were compared to those of 71 office workers living in Eordea valley (Group C) and to 96 living in Grevena, a region without pollution (Group D). The study included the completion of the MRC questionnaire for the detection of respiratory diseases, pulmonary function tests, measurement of diffusion capacity, otorhinolaryngologic examination, rhinomanonetry as well as chest and paranasal cavity X-rays. Chronic bronchitis was reported by 26.8%, 24.8%, 17.9% and 10.6% respectively of the subjects of groups A, B, C and D according to the answers of the questionnaire (p<0.001). The spirometry and diffusion capacity findings presented no considerable differences either in the 4 groups or between phases I and II of the study. The main problems were detected in the upper airways. A very high prevalence of severe nasal obstruction (73%, 71.2%, 55.7% and 19.3% in Groups A, B, C and D respectively) was detected. Furthermore, a high percentage of atrophic rhinitis (14%) was detected both among workers (Groups A and B) and subjects living in the Eordea valley who participated as controls (Group C). From the X-rays, hypertrophy of nasal turbinates-cartilage and polyposis was observed as follows: Group A: 53.9%, Group B: 48.1%, Group C: 46.5% and Group D: 20.3% (p<0.001). The findings related to the upper respiratory system may be due to excessive pollution by airborne particles (fly ash) pollution in the region and particularly to chromium, nickel, cobalt and lead found at high concentration levels in airborne dust. A marked association between the total air-flow in the nose and the mid-expiratory flow (p<0.01) was detected. We conclude that subjects working in lignite mines under conditions of excessive pollution by airborne contaminants have a high prevalence of atrophic rhinitis and, in addition to other standard examinations, should undergo rhinomanometry testing and X-ray imaging of the paranasal cavities.
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Air impacts from three alternatives for producing JP-8 jet fuel.
Kositkanawuth, Ketwalee; Gangupomu, Roja Haritha; Sattler, Melanie L; Dennis, Brian H; MacDonnell, Frederick M; Billo, Richard; Priest, John W
2012-10-01
To increase U.S. petroleum energy independence, the University of Texas at Arlington (UT Arlington) has developed a direct coal liquefaction process which uses a hydrogenated solvent and a proprietary catalyst to convert lignite coal to crude oil. This sweet crude can be refined to form JP-8 military jet fuel, as well as other end products like gasoline and diesel. This paper presents an analysis of air pollutants resulting from using UT Arlington's liquefaction process to produce crude and then JP-8, compared with 2 alternative processes: conventional crude extraction and refining (CCER), and the Fischer-Tropsch process. For each of the 3 processes, air pollutant emissions through production of JP-8 fuel were considered, including emissions from upstream extraction/ production, transportation, and conversion/refining. Air pollutants from the direct liquefaction process were measured using a LandTEC GEM2000 Plus, Draeger color detector tubes, OhioLumex RA-915 Light Hg Analyzer, and SRI 8610 gas chromatograph with thermal conductivity detector. According to the screening analysis presented here, producing jet fuel from UT Arlington crude results in lower levels of pollutants compared to international conventional crude extraction/refining. Compared to US domestic CCER, the UTA process emits lower levels of CO2-e, NO(x), and Hg, and higher levels of CO and SO2. Emissions from the UT Arlington process for producing JP-8 are estimated to be lower than for the Fischer-Tropsch process for all pollutants, with the exception of CO2-e, which were high for the UT Arlington process due to nitrous oxide emissions from crude refining. When comparing emissions from conventional lignite combustion to produce electricity, versus UT Arlington coal liquefaction to make JP-8 and subsequent JP-8 transport, emissions from the UT Arlington process are estimated to be lower for all air pollutants, per MJ of power delivered to the end user. The United States currently imports two-thirds of its crude oil, leaving its transportation system especially vulnerable to disruptions in international crude supplies. At current use rates, U.S. coal reserves (262 billion short tons, including 23 billion short tons lignite) would last 236 years. Accordingly, the University of Texas at Arlington (UT Arlington) has developed a process that converts lignite to crude oil, at about half the cost of regular crude. According to the screening analysis presented here, producing jet fuel from UT Arlington crude generates lower levels of pollutants compared to international conventional crude extraction/refining (CCER).
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30 CFR 75.380 - Escapeways; bituminous and lignite mines.
Code of Federal Regulations, 2014 CFR
2014-07-01
..., ramps, or similar facilities where the escapeways cross over obstructions. (7) Provided with a... specific conditions, which is approved by the district manager. (2) Paragraphs (f)(3) through (f)(7) of... escapeway, except for continuous miners and as provided in paragraphs (f)(5), (f)(6), and (f)(7) of this...
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30 CFR 75.380 - Escapeways; bituminous and lignite mines.
Code of Federal Regulations, 2013 CFR
2013-07-01
..., ramps, or similar facilities where the escapeways cross over obstructions. (7) Provided with a... specific conditions, which is approved by the district manager. (2) Paragraphs (f)(3) through (f)(7) of... escapeway, except for continuous miners and as provided in paragraphs (f)(5), (f)(6), and (f)(7) of this...
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30 CFR 75.380 - Escapeways; bituminous and lignite mines.
Code of Federal Regulations, 2012 CFR
2012-07-01
..., ramps, or similar facilities where the escapeways cross over obstructions. (7) Provided with a... specific conditions, which is approved by the district manager. (2) Paragraphs (f)(3) through (f)(7) of... escapeway, except for continuous miners and as provided in paragraphs (f)(5), (f)(6), and (f)(7) of this...
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Geographic Information Systems as Applied to the Manipulation of Environmental Data.
ERIC Educational Resources Information Center
Hill, J. M.; And Others
1983-01-01
Discusses two aspects of a Geographic Information System (GIS), a computerized system for processing geographic and/or mapped data and components/implementation of a GIS and GIS demonstration in natural resources management. Demonstrations related to lignite mining permit requirements in coastal zone, and location of potential landfills/hazardous…
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ELEMENTAL MERCURY CAPTURE BY ACTIVATED CARBON IN A FLOW REACTOR
The paper gives results of bench-scale experiments in a flow reactor to simulate the entrained-flow capture of elemental mercury (Hgo) using solid sorbents. Adsorption of Hgo by a lignite-based activated carbon (Calgon FGD) was examined at different carbon/mercury (C/Hg) rat... -
30 CFR 75.380 - Escapeways; bituminous and lignite mines.
Code of Federal Regulations, 2011 CFR
2011-07-01
..., ramps, or similar facilities where the escapeways cross over obstructions. (7) Provided with a... specific conditions, which is approved by the district manager. (2) Paragraphs (f)(3) through (f)(7) of... escapeway, except for continuous miners and as provided in paragraphs (f)(5), (f)(6), and (f)(7) of this...
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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...
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Field Evaluations of Commercial Humic Products: Current Knowledge and Future Needs.
USDA-ARS?s Scientific Manuscript database
Humic products are extracts of lignite or leonardite, which are immature coals. Humic products are sold commercially; their advertisements claim they will improve plant growth when applied to plants or soil. They are bought by small proportions of row crop farmers and growers of flowers, vegetables,...
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ERIC Educational Resources Information Center
Clamp, Alice
1991-01-01
The energy policies of four emerging democratic governments in Eastern Europe are individually profiled with respect to the challenge of producing more electrical energy, while creating less pollution and cleaning up the existing environmental disorder. Highlighted is the possible change from the burning of lignite coal to use of nuclear reactors.…
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40 CFR 60.45Da - Standard for mercury (Hg).
Code of Federal Regulations, 2010 CFR
2010-07-01
...-fired electric utility steam generating unit that burns only lignite, you must not discharge into the... (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Electric Utility... for mercury (Hg). (a) For each coal-fired electric utility steam generating unit other than an IGCC...
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Sucharova, Julie; Suchara, Ivan; Hola, Marie; Reimann, Clemens; Boyd, Rognvald; Filzmoser, Peter; Englmaier, Peter
2011-05-01
While terrestrial moss and other plants are frequently used for environmental mapping and monitoring projects, data on the regional geochemistry of humus are scarce. Humus, however, has a much larger life span than any plant material. It can be seen as the "environmental memory" of an area for at least the last 60-100 years. Here concentrations of 39 elements determined by ICP-MS and ICP AES, pH and ash content are presented for 259 samples of forest floor humus collected at an average sample density of 1 site/300 km2 in the Czech Republic. The scale of anomalies linked to known contamination sources (e.g., lignite mining and burning, metallurgical industry, coal fired power plants, metal smelters) is documented and discussed versus natural processes influencing humus quality. Most maps indicate a local impact from individual contamination sources: often more detailed sampling than used here would be needed to differentiate between likely sources. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Datasets for Ostrava PMF paper
These data support a published journal paper described as follows:A 14-week investigation during a warm and cold seasons was conducted to improve understanding of airpollution sources that might be impacting air quality in Ostrava, the Czech Republic. Fine particulatematter (PM2.5) samples were collected in consecutive 12-h day and night increments during spring andfall 2012 sampling campaigns. Sampling sites were strategically located to evaluate conditions in closeproximity of a large steel works industrial complex, as well as away from direct influence of theindustrial complex. These samples were analyzed for metals and other elements, organic and elemental(black) carbon, and polycyclic aromatic hydrocarbons (PAHs). The PM2.5 samples were supplementedwith pollutant gases and meteorological parameters. We applied the EPA PMF v5.1 model with uncertainty estimate features to the Ostrava data set. Using the model's bootstrapping procedure and other considerations, six factors were determined to provide the optimum solution. Each model run consisted of 100 iterations to ensure that the solution represents a global minimum. The resulting factors were identified as representing coal (power plants), mixed Cl, crustal, industrial 1 (alkali metals and PAHs), industrial 2 (transition metals), and home heat/transportation. The home heating source is thought to be largely domestic boilers burning low quality fuels such as lignite, wood, and domestic waste.Transportation-r
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NASA Astrophysics Data System (ADS)
Seyedbagheri, Mir
2017-04-01
In continuation of over 35 years of on-farm studies on soil organic matter from different humates (functional carbon) and compost, I have documented quantitative improvements in soil health and water-use efficiency. The ability of soil organic matter to bind water has become an important theme for research in past years. Research trials were established to evaluate the efficacy of different commercial functional carbon products derived from Leonardite (highly oxidized lignite) in crop production. In each of these trials, functional carbon (Humic and Fulvic acids) products were used in a randomized complete block design. The use of humic substances creates strong organo-mineral complexes (aggregation), chelation, as well as enhanced buffering capacities. We evaluated data from 3 fields and compared the results. Our observation and field demonstrations indicated there was a marked increase in water retention. Data from humic acid (HA) trials showed that different cropping systems responded differently to different products in relation to yield and quality. The functional carbon products used in the study seemed to enhance fertilizer and water-use efficiency by increasing complexation, chelation and buffering. The consistent use of good quality functional carbons in our replicated plots resulted in a yield increase from 6% to 30% over several decades.
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76 FR 14058 - Notice of Inventory Completion: Fremont County Coroner, Riverton, WY
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-15
... associated funerary objects are 2 fragments of freshwater clam shells, 32 dentalia shell beads, 2 bird bone beads, 8 chokecherry seed beads, 162 bone heishi-style beads, 158 lignite heishi-style beads, 5 fragmentary bone heishi-style beads, 1 shell bead, and 3 chert microflakes. The Sinks Canyon site is located...
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Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Air quantity. 75.325 Section 75.325 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.325 Air quantity. (a)(1) In bituminous and lignite mines the quantity of air shall be at least 3,000 cubic feet per minute reaching each working face...
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Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Air quantity. 75.325 Section 75.325 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.325 Air quantity. (a)(1) In bituminous and lignite mines the quantity of air shall be at least 3,000 cubic feet per minute reaching each working face...
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Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Air quantity. 75.325 Section 75.325 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.325 Air quantity. (a)(1) In bituminous and lignite mines the quantity of air shall be at least 3,000 cubic feet per minute reaching each working face...
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20 CFR 725.101 - Definition and use of terms.
Code of Federal Regulations, 2011 CFR
2011-04-01
... the surface of such land by any person, used in, or to be used in, or resulting from, the work of... means or method, and in the work of preparing the coal so extracted, and includes custom coal..., mixing, storing and loading of bituminous coal, lignite or anthracite, and such other work of preparing...
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Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Air quantity. 75.325 Section 75.325 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.325 Air quantity. (a)(1) In bituminous and lignite mines the quantity of air shall be at least 3,000 cubic feet per minute reaching each working face...
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Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Air quantity. 75.325 Section 75.325 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.325 Air quantity. (a)(1) In bituminous and lignite mines the quantity of air shall be at least 3,000 cubic feet per minute reaching each working face...
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20 CFR 410.110 - General definitions and use of terms.
Code of Federal Regulations, 2010 CFR
2010-04-01
... Section 410.110 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE HEALTH AND SAFETY ACT... Health and Safety Act of 1969 (Pub. L. 91-173), enacted December 30, 1969, as amended by the Black Lung... be used in, or resulting from, the work of extracting in such area bituminous coal, lignite, or...
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Coal Gasification Processes for Retrofitting Military Central Heating Plants: Overview
1992-11-01
the water runoff has minimum contamination. The coal pile is located on a waterproof base to prevent water seepage into the ground. All runoff water...United Arab Naphtha Republic Chemical Fertili - Lignite Dust 1 217,000 Ammonia 1963 zer Company Ltd. Synthesis of Thailand, Ferti- lizer Plant in Mae Moh
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Hatcher, P.G.
1988-01-01
A series of decomposed and coalified gymnosperm woods was examined by conventional solid-state 13C nuclear magnetic resonance (NMR) and by dipolar-dephasing NMR techniques. The results of these NMR studies for a histologically related series of samples provide clues as to the nature of codification reactions that lead to the defunctionalization of lignin-derived aromatic structures. These reactions sequentially involve the following: (1) loss of methoxyl carbons from guaiacyl structural units with replacement by hydroxyls and increased condensation; (2) loss of hydroxyls or aryl ethers with replacement by hydrogen as rank increases from lignin to high-volatile bituminous coal; (3) loss of alkyl groups with continued replacement by hydrogen. The dipolar-dephasing data show that the early stages of coalification in samples examined (lignin to lignite) involve a decreasing degree of protonation on aromatic rings and suggest that condensation is significant during coalification at this early stage. An increasing degree of protonation on aromatic rings is observed as the rank of the sample increases from lignite to anthracite.
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Olea, Ricardo A.; Luppens, James A.
2012-01-01
There are multiple ways to characterize uncertainty in the assessment of coal resources, but not all of them are equally satisfactory. Increasingly, the tendency is toward borrowing from the statistical tools developed in the last 50 years for the quantitative assessment of other mineral commodities. Here, we briefly review the most recent of such methods and formulate a procedure for the systematic assessment of multi-seam coal deposits taking into account several geological factors, such as fluctuations in thickness, erosion, oxidation, and bed boundaries. A lignite deposit explored in three stages is used for validating models based on comparing a first set of drill holes against data from infill and development drilling. Results were fully consistent with reality, providing a variety of maps, histograms, and scatterplots characterizing the deposit and associated uncertainty in the assessments. The geostatistical approach was particularly informative in providing a probability distribution modeling deposit wide uncertainty about total resources and a cumulative distribution of coal tonnage as a function of local uncertainty.
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Green synthesis of carbon quantum dots from lignite coal and the application in Fe3+ detection
NASA Astrophysics Data System (ADS)
Liu, Xuexia; Hao, Juanyuan; Liu, Jianhui; Tao, Hongcai
2018-02-01
Carbon quantum dots (CQDs) had attracted much attention due to their unique structures and excellent properties. Their green preparation was one of the research frontiers. However, most of the CQDs were prepared by strong acid oxidation, the way of which was not friendly to the environment. In this study, CQDs were prepared by green ozone oxidation of lignite coal, which is abundant and inexpensive. The CQDs were well dispersed, the size distribution of the obtained CQDs centralized from 2 to 4 nm with the average diameter of about 2.8 nm. In addition, the as-prepared CQDs containing rich oxygen functional groups exhibited good water-solubility and optical properties with yield reached 35%. The CQDs showed a highly sensitive and selective quenching effect to Fe3+ with desirable anti-interference performance. Moreover, the fluorescence intensity of CQDs had a good linear response to the Fe3+ concentration ranging from 10 to 150 µmol/L with the detection limit of 0.26 µmol/L. This green and facile synthesis method had the prospect of large-scale preparation of CQDs.
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Keighin, C.W.M.; Flores, R.M.; Rowland, T.
1996-01-01
Carbonate concretionary bodies were encountered during mining of the Beulah-Zap lignite seam in the Coteau Properties' Freedom mine, Mercer County, North Dakota. Preliminary studies show that areal and vertical distribution of the concretions are variable. All concretions examined are composed almost entirely of calcite. They occur as thin tabular bodies, as more or less elliptical forms, or as tear shaped bodies, and may occur individually or as clusters of buff-colored, poorly consolidated to solidly crystalline material. The carbonate masses vary in size from a few millimeters to tens of centimeters. Bedding in the lignite may display some compactional folding over dense spheroidal to elliptical concretions, indicating formation of the concretions prior to compaction. Internal morphology of the concretions is complex, and includes cone-in-cone structure, cross-cutting calcite veinlets, and multiple generations of calcite. Carbon isotope values suggest the concretions are composed of biogenic carbonate, probably related to early diagenesis and decomposition of organic matter (peat); oxygen isotope values are light, and consistent with a freshwater origin.
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Organic emissions from coal pyrolysis: mutagenic effects.
Braun, A G; Wornat, M J; Mitra, A; Sarofim, A F
1987-01-01
Four different types of coal have been pyrolyzed in a laminar flow, drop tube furnace in order to establish a relationship between polycyclic aromatic compound (PAC) evolution and mutagenicity. Temperatures of 900K to 1700K and particle residence times up to 0.3 sec were chosen to best simulate conditions of rapid rate pyrolysis in pulverized (44-53 microns) coal combustion. The specific mutagenic activity (i.e., the activity per unit sample weight) of extracts from particulates and volatiles captured on XAD-2 resin varied with coal type according to the order: subbituminous greater than high volatile bituminous greater than lignite greater than anthracite. Total mutagenic activity (the activity per gram of coal pyrolyzed), however, varied with coal type according to the order: high volatile bituminous much greater than subbituminous = lignite much greater than anthracite, due primarily to high organic yield during high volatile bituminous coal pyrolysis. Specific mutagenic activity peaked in a temperature range of 1300K to 1500K and generally appeared at higher temperatures and longer residence times than peak PAC production. PMID:3311724
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Mu, Lin; Chen, Jianbiao; Yao, Pikai; Zhou, Dapeng; Zhao, Liang; Yin, Hongchao
2016-12-01
Co-pyrolysis characteristics of petrochemical wastewater sludge and Huolinhe lignite were investigated using thermogravimetric analyzer and packed-bed reactor coupled with Fourier transform infrared spectrometer and gas chromatography. The pyrolysis characteristics of the blends at various sludge blending ratios were compared with those of the individual materials. Thermogravimetric experiments showed that the interactions between the blends were beneficial to generate more residues. In packed-bed reactor, synergetic effects promoted the release of gas products and left less liquid and solid products than those calculated by additive manner. Fourier transform infrared spectrometer analysis showed that main functional groups in chars gradually disappeared with pyrolysis temperatures increasing, and H 2 O, CH 4 , CO, and CO 2 appeared in volatiles during pyrolysis. Gas compositions analysis indicated that, the yields of H 2 and CO clearly increased as the pyrolysis temperature and sludge blending ratio increasing, while the changes of CH 4 and CO 2 yields were relatively complex. Copyright © 2016 Elsevier Ltd. All rights reserved.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Young, B.C.; Musich, M.A.
A fixed-bed reactor system with continuous Hg{sup 0} analysis capabilities was used to evaluate commercial carbon sorbents for the removal of elemental mercury from simulated flue gas. The objectives of the program were to compare the sorbent effectiveness under identical test conditions and to identify the effects of various flue gas components on elemental mercury sorption. Sorbents tested included steam-activated lignite, chemically activated hardwood, chemically activated bituminous coal, iodated steam-activated coconut shell, and sulfur-impregnated steam-activated bituminous coal. The iodated carbon was the most effective sorbent, showing over 99% mercury removal according to U.S. Environmental Protection Agency (EPA) Method 101A. Datamore » indicate that adding O{sub 2} at 4 vol% reduced the effectiveness of the steam-activated lignite, chemically activated hardwood, and sulfur- impregnated steam-activated bituminous coal. Adding SO{sub 2} at 500 ppm improved the mercury removal of the sulfur-impregnated carbon. Further, the presence of HCl gas (at 50 ppm) produced an order of magnitude increase in mercury removal with the chemically activated and sulfur-impregnated bituminous coal-based carbons.« less
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NASA Technical Reports Server (NTRS)
Des Marais, D. J.; Stallard, M. L.; Nehring, N. L.; Truesdell, A. H.
1988-01-01
Hydrocarbon abundances and stable-isotopic compositions were measured in wells M5, M26, M35 and M102, which represent a range of depths (1270-2000 m) and temperatures (275-330 degrees C) in the field. In order to simulate the production of the geothermal hydrocarbons, gases were collected from the pyrolysis of lignite in the laboratory. This lignite was obtained from a well which sampled rock strata which are identical to those occurring in the field, but which have experienced much lower subsurface temperatures. In both the well and the laboratory observations, high-temperature environments favored higher relative concentrations of methane, ethane and benzene and generally higher delta 13C-values in the individual hydrocarbons. The best correlation between the laboratory and well data is obtained when laboratory-produced gases from experiments conducted at lower (400 degrees C) and higher (600 degrees C) temperatures are mixed. This improved correlation suggests that the wells are sampling hydrocarbons produced from a spectrum of depths and temperatures in the sediments.
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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
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Kalkhoff, S.J.
1985-01-01
The U.S. Geological Survey, in cooperation with the Mississippi Department of Natural Resources, Bureau of Geology, is conducting a hydrologic data collection program in potential lignite-producing areas in Mississippi. During the last two weeks of August 1984, hydrologic data were collected at 15 stream sites that drain potential lignite mining areas in Lafayette, Calhoun, and Yalobusha Counties. Main channel widths ranged from approximately 60 feet at three streams (Coon Creek near Toccopula, Muckaloon Creek near Tula, and Hurricane Creek near Velma) to approximately 120 feet at two streams (Potlockney Creek near Tula, and Savannah Creek near Bruce). Maximum water depths ranged from less than 1.0 foot at most streams to over 5.0 feet at sites on Potlockney Creek near Tula and McGill Creek near Sarepta. Stream discharge ranged from 0.32 cubic feet per second in Persimmon Creek near Bruce to 18.5 cubic feet per second in Puskus Creek near Etta. The specific conductance of stream water ranged from 25 to 160 microsiemens and dissolved solids concentrations ranged from 22 to 91 mg/L (milligrams per liter). Most major ion concentrations were less than 10 mg/L with the exception of calcium (11 mg/L), sodium (12 mg/L) and sulfate (18 mg/L) in the water of Persimmon Creek near Bruce. Dissolved oxygen concentrations were greater than 5.0 mg/L at all but one site. Turbidity values were generally less than 50 units. Nitrate plus nitrite concentrations were equal to or less than 0.10 mg/L in all streams except in Potlockney Creek near Tula where the concentration was 0.11 mg/L. Copper and selenium concentrations in the water at all sampling sites ranged from below the detection limits (1 microgram/g) to 4 micrograms/g (micrograms per gram) and mercury concentrations in bottom material samples ranged from less than 0.01 microgram/g to 0.15 microgram/g. (USGS)
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NASA Astrophysics Data System (ADS)
Pękala, Agnieszka
2017-10-01
As part of an integrated system of environmental protection at every stage of the product life cycle such as: raw material extraction, its transportation and processing as well the subsequent use and development is required to carry out actions towards reducing or completely eliminating products that contain harmful substances to the environment. The purpose of the presented paper is an analysis of the toxic element concentrations in the extracted siliceous minerals at the initial stage of the raw material recognition. The research material is constituted by rocks collected from the Mesozoic bedrock from the Bełchatów lignite deposit. A group of the studied rocks is represented by diatomites, gaizes, opoka-rocks and light opoka-rocks, enriched with minerals from the group of SiO2. Most of the recognized petrographic sediments have a real possibility of potential applications in the building material industry, but it needs to carry out a detailed and thorough research. The studies of the chemical composition were determined by atomic absorption spectroscopy (AAS) using Philips PU 9100Xi Camera SX-100 spectrometer and an atomic emission spectroscopy with inductively coupled plasma (ICP AES) using PLASMA 40 spectrometer. There were carried out a chemical analyses and determined the content of some toxic elements: Pb, Cr, Cd, Ni, Zn, Cu, Co, As, Sr, Ba, Zr. in the studied sedimentary rocks. The analysis of the results draws attention to the high content of cadmium in the case of the studied sediments. The concentration of this element in the described rocks is an average of 0.22 mg/kg -the diatomites, 0.05 mg/kg -the gaizes, 0.4 mg/kg -the opoka-rocks, 2.23 mg/kg -the light opoka-rocks. It was moreover registered varied concentration of arsenic in diatomites, that is formed in the range of 0.05 - 9.6 mg/kg, an average of 6.3 mg/kg. The content of the other designated elements with toxic properties in the analysed groups of rocks does not exceed the limit values. An increased concentration of cadmium and arsenic should be considered as an important information in resource research of the studied rocks. The both elements belong to the easily soluble elements as a result of weathering processes. Cadmium is one of the most dangerous toxicological environmental elements. It is easily absorbed and relatively long stopped in humans and animal’s organism. It also seems that the increased concentration in the siliceous rocks results from the nature of the lignite from the Bełchatów lignite deposit, outstanding higher cadmium content in relation to the observed lignite of the world.
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NASA Astrophysics Data System (ADS)
Karaca, Hüseyin; Koyunoglu, Cemil
2017-12-01
Most coal hydrogenation processes require a large quantity of hydrogen. In general, a coal derived liquid such as anthracene oil was used as a hydrogen donor solvent. Tetralin, partially hydrogenated pyrene, phenantrene and coal-derived solvents, which contain hydroaromatic compounds, are efficient solvents to donate hydrogen. In an attempt to reduce the high cost of hydrogen, part of the hydrogen was replaced by a low cost hydrogen donor solvent. This must be hydrogenated during or before the process and recycled. To reduce the cost of hydrogen donor vehicles instead of liquids recycled from the liquefaction process or several biomass types, industrial by products, liquid fractions derived from oil sands bitumen were successfully used to solubilize a coal from the past. In an attempt to reduce the high cost of hydrogen, part of the hydrogen was replaced by a low cost hydrogen donor solvent. However, when hydrogen is supplied from the hydroaromatic structures present in the solvent, the activity of coal minerals is too low to rehydrogenate the solvent in-situ. Nevertheless, a decrease of using oxygen, in addition to enhanced usage of the hydrogen supply by using various waste materials might lead to a decrease of the cost of the liquefaction procedure. So instead of using tetralin another feeding material such as biomass is becoming another solution improving hydrogen donor substances. Most of the liquefaction process were carried out in a batch reactor, in which the residence time of the liquefaction products is long enough to favour the retrogressive reactions, early studies which are related to liquefaction of coal with biomass generally focus on the synergetic effects of coal while biomass added. Early studies which are related to liquefaction of coal with biomass generally focus on the synergetic effects of coal while biomass added. Alternatively, to understand the hydrogen transfer from biomass to coal, in this study, Elbistan Lignite (EL) with manure, tea pulp and waste plastic liquefied and to understand hydrogen quantity change after liquefaction, (H/C)atomic ratio of products obtained. Due to the highest oil conversion of manure biomass and highest (H/C)atomic ratio results show manure is the favourable biomass for EL amongst the other biomass used. And liquid/solid ratio optimized. About high total conversion of oil products the optimum ratio obtained as 3/1. And also EL with manure liquefied with the w/EL ratio between 0:1 to 1:1. As a result, by thinking about the yield values obtained, the optimum waste to lignite ratio found to be 1:1.
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Justification of rational parameters of briquetting using mechanic activation techniques
NASA Astrophysics Data System (ADS)
Nikolaeva, L. A.; Burenina, O. N.
2017-12-01
The paper illustrates results of development of technology and compositions of briquetting substandard lignite waste with the use of tar as a binder, modified with mechanically activated organic-mineral fillers. The influence of highly disperse additives and technological briquetting regimes on the structure formation and the qualitative characteristics of fuel brown coal briquettes is considered.
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Knudson, Curtis L.
1993-01-01
A process of preparing lignite (low rank) coal filter material, suitable for use in lieu of more expensive activated carbon filter materials, is disclosed. The process comprises size reducing Leonardite coal material to a suitable filtering effective size, and thereafter heating the size reduced Leonardite preferably to at least 750.degree. C. in the presence of a flow of an inert gas.
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Knudson, C.L.
1993-10-19
A process of preparing lignite (low rank) coal filter material, suitable for use in lieu of more expensive activated carbon filter materials, is disclosed. The process comprises size reducing Leonardite coal material to a suitable filtering effective size, and thereafter heating the size reduced Leonardite preferably to at least 750 C in the presence of a flow of an inert gas. 1 figure.
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Application of LANDSAT data and digital image processing. [Ruhr Valley, Germany
NASA Technical Reports Server (NTRS)
Bodechtel, J. (Principal Investigator)
1978-01-01
The author has identified the following significant results. Based on LANDSAT 1 and 2 data, applications in the fields of coal mining, lignite exploration, and thematic mapping in geology are demonstrated. The hybrid image processing system, its software, and its utilization for educational purposes is described. A pre-operational European satellite is proposed.
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Rouse, William A.; Houseknecht, David W.
2012-01-01
The Cook Inlet-Susitna region of south-central Alaska contains large quantities of gas-bearing coal of Tertiary age. The U.S. Geological Survey in 2011 completed an assessment of undiscovered, technically recoverable coal-bed gas resources underlying the Cook Inlet-Susitna region based on the total petroleum system (TPS) concept. The Cook Inlet Coal-Bed Gas TPS covers about 9,600,000 acres and comprises the Cook Inlet basin, Matanuska Valley, and Susitna lowland. The TPS contains one assessment unit (AU) that was evaluated for coal-bed gas resources between 1,000 and 6,000 feet in depth over an area of about 8,500,000 acres. Coal beds, which serve as both the source and reservoir for natural gas in the AU, were deposited during Paleocene-Pliocene time in mires associated with a large trunk-tributary fluvial system. Thickness of individual coal beds ranges from a few inches to more than 50 feet, with cumulative coal thickness of more than 800 feet in the western part of the basin. Coal rank ranges from lignite to subbituminous, with vitrinite reflectance values less than 0.6 percent throughout much of the AU. The AU is considered hypothetical because only a few wells in the Matanuska Valley have tested the coal-bed reservoirs, so the use of analog coal-bed gas production data was necessary for this assessment. In order to estimate reserves that might be added in the next 30 years, coal beds of the Upper Fort Union Formation in the Powder River Basin of Wyoming and Montana were selected as the production analog for Tertiary coal beds in the Cook Inlet-Susitna region. Upper Fort Union coal beds have similar rank (lignite to subbituminous), range of thickness, and coal-quality characteristics as coal beds of the Tertiary Kenai Group. By use of this analog, the mean total estimate of undiscovered coal-bed gas in the Tertiary Coal-Bed Gas AU is 4.674 trillion cubic feet (TCF) of gas.
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Stankiewicz, B.A.; Kruge, M.A.; Crelling, J.C.; Salmon, G.L.
1994-01-01
Samples of organic matter from nine well-known geological units (Green River Fm., Tasmanian Tasmanite, Lower Toarcian Sh. of the Paris Basin, Duwi Fm., New Albany Sh., Monterey Fm., Herrin No. 6 coal, Eocene coal, and Miocene lignite from Kalimantan) were processed by density gradient centrifugation (DGC) to isolate the constituent macerals. Optimal separation, as well as the liberation of microcrystalline pyrite from the organic matter, was obtained by particle size minimization prior to DGC by treatment with liquid N2 and micronization in a fluid energy mill. The resulting small particle size limits the use of optical microscopy, thus microfluorimetry and analytical pyrolysis were also employed to assess the quality and purity of the fractions. Each of the samples exhibits one dominant DGC peak (corresponding to alginite in the Green River Fm., amorphinite in the Lower Toarcian Sh., vitrinite in the Herrin No. 6, etc.) which shifts from 1.05 g mL-1 for the Type I kerogens to between 1.18 and 1.23 g mL-1 for Type II and II-S. The characteristic densities for Type III organic matter are greater still, being 1.27 g mL-1 for the hydrogen-rich Eocene coal, 1.29 g mL-1 for the Carboniferous coal and 1.43 g mL-1 for the oxygen-rich Miocene lignite. Among Type II kerogens, the DGC profile represents a compositional continuum from undegraded alginite through (bacterial) degraded amorphinite; therefore chemical and optical properties change gradually with increasing density. The separation of useful quantities of macerals that occur in only minor amounts is difficult. Such separations require large amounts of starting material and require multiple processing steps. Complete maceral separation for some samples using present methods seems remote. Samples containing macerals with significant density differences due to heteroatom diversity (e.g., preferential sulfur or oxygen concentration in the one maceral), on the other hand, may be successfully separated (e.g., coals and Monterey kerogen). ?? 1994 American Chemical Society.
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Recovery of solid fuel from municipal solid waste by hydrothermal treatment using subcritical water
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hwang, In-Hee, E-mail: hwang@eng.hokudai.ac.jp; Aoyama, Hiroya; Matsuto, Toshihiko
2012-03-15
Highlights: Black-Right-Pointing-Pointer Hydrothermal treatment using subcritical water was studied to recover solid fuel from MSW. Black-Right-Pointing-Pointer More than 75% of carbon in MSW was recovered as char. Black-Right-Pointing-Pointer Heating value of char was comparable to that of brown coal and lignite. Black-Right-Pointing-Pointer Polyvinyl chloride was decomposed at 295 Degree-Sign C and 8 MPa and was removed by washing. - Abstract: Hydrothermal treatments using subcritical water (HTSW) such as that at 234 Degree-Sign C and 3 MPa (LT condition) and 295 Degree-Sign C and 8 MPa (HT condition) were investigated to recover solid fuel from municipal solid waste (MSW). Printing paper,more » dog food (DF), wooden chopsticks, and mixed plastic film and sheets of polyethylene, polypropylene, and polystyrene were prepared as model MSW components, in which polyvinylchloride (PVC) powder and sodium chloride were used to simulate Cl sources. While more than 75% of carbon in paper, DF, and wood was recovered as char under both LT and HT conditions, plastics did not degrade under either LT or HT conditions. The heating value (HV) of obtained char was 13,886-27,544 kJ/kg and was comparable to that of brown coal and lignite. Higher formation of fixed carbon and greater oxygen dissociation during HTSW were thought to improve the HV of char. Cl atoms added as PVC powder and sodium chloride to raw material remained in char after HTSW. However, most Cl originating from PVC was found to converse into soluble Cl compounds during HTSW under the HT condition and could be removed by washing. From these results, the merit of HTSW as a method of recovering solid fuel from MSW is considered to produce char with minimal carbon loss without a drying process prior to HTSW. In addition, Cl originating from PVC decomposes into soluble Cl compound under the HT condition. The combination of HTSW under the HT condition and char washing might improve the quality of char as alternative fuel.« less
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Delgado-Martin, J; Juncosa-Rivera, R; Falcón-Suárez, I; Canal-Vila, J
2013-11-01
Following the technical closure of the brown lignite Meirama mine (NW Spain) in April 2008, the reclamation of the mined area is being accomplished with the controlled flooding of its large pit. During the first 7 months of flooding, the sequential arrest of the ground water dewatering system led to the growth of an acidic water body of about 2 hm3. Since October 2008, the surface waters from some local streams have been diverted towards the pit so that these have become the major water input in the flooding process. Surface water has promoted a major change in the chemical composition of the lake water so that, at present, its surface has a circum neutral pH, net alkalinity, and low conductivity. At present, the lake has slightly more than one half of its final volume, and it is expected the overflow in 3 to 3.5 years. The lake is meromictic, with a sharp chemocline separating the acidic monimolimnion (pH≈3.2, acidity≈150 mg CaCO3/L, κ 25≈2.4 mS/cm) from the main water body (pH≈6.5, alkalinity≈15 mg CaCO3/L, κ 25≈0.3 mS/cm). Oxygen is being depleted at the bottom of the lake so that the monimolimnion became anoxic in January 2011. Above the chemocline, the composition of the lake is similar, but not identical, to that of the flooding stream waters. Close to the surface, some constituents (pH, metals) show strong seasonal variations in coincidence with the phytoplankton growing periods. Those parameters whose limits are legally prescribed comply with the corresponding water quality standards, and they are also consistent with the forecasting results obtained in early modeling. At present, a project considering the construction of an uptake tunnel to exploit the lake is being developed for the emergency water supply of the metropolitan area of A Coruña.
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Biogeochemical processes controlling density stratification in an iron-meromictic lake
NASA Astrophysics Data System (ADS)
Nixdorf, E.; Boehrer, B.
2015-06-01
Biogeochemical processes and mixing regime of a lake can control each other mutually. The prominent case of iron meromixis is investigated in Waldsee near Doebern, a small lake that originated from surface mining of lignite. From a four years data set of monthly measured electrical conductivity profiles, we calculated summed conductivity as a quantitative variable reflecting the amount of electro-active substances in the entire lake. Seasonal variations followed changing chemocline height. Coinciding changes of electrical conductivities in the monimolimnion indicated that a considerable share of substances, precipitated by the advancing oxygenated epilimnion, re-dissolved in the remaining anoxic deep waters and contributed considerably to the density stratification. In addition, we constructed a lab experiment, in which aeration of monimolimnetic waters removed iron compounds and organic material. Precipitates could be identified by visual inspection. Introduced air bubbles ascended through the water column and formed a water mass similar to the mixolimnetic Waldsee water. The remaining less dense water remained floating on the nearly unchanged monimolimnetic water. In conclusion, iron meromixis as seen in Waldsee did not require two different sources of incoming waters, but the inflow of iron rich deep groundwater and the aeration through the lake surface were fully sufficient.
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Reuse of thermosetting plastic waste for lightweight concrete.
Panyakapo, Phaiboon; Panyakapo, Mallika
2008-01-01
This paper presents the utilization of thermosetting plastic as an admixture in the mix proportion of lightweight concrete. Since this type of plastic cannot be melted in the recycling process, its waste is expected to be more valuable by using as an admixture for the production of non-structural lightweight concrete. Experimental tests for the variation of mix proportion were carried out to determine the suitable proportion to achieve the required properties of lightweight concrete, which are: low dry density and acceptable compressive strength. The mix design in this research is the proportion of plastic, sand, water-cement ratio, aluminum powder, and lignite fly ash. The experimental results show that the plastic not only leads to a low dry density concrete, but also a low strength. It was found that the ratio of cement, sand, fly ash, and plastic equal to 1.0:0.8:0.3:0.9 is an appropriate mix proportion. The results of compressive strength and dry density are 4.14N/mm2 and 1395 kg/m3, respectively. This type of concrete meets most of the requirements for non-load-bearing lightweight concrete according to ASTM C129 Type II standard.
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20 CFR 410.110 - General definitions and use of terms.
Code of Federal Regulations, 2011 CFR
2011-04-01
... be used in, or resulting from, the work of extracting in such area bituminous coal, lignite, or anthracite from its natural deposits in the earth by any means or method, and the work of preparing the coal... who performs the services, not only as to the result to be accomplished by the work but also as to the...
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Schmidt, Axel; Schubert, Michael
2007-12-01
Groundwater discharge into an open pit lignite mining lake was investigated using radon-222 as a naturally occurring environmental tracer. The chosen study site was a meromictic lake, i.e., a water body that is divided horizontally into two separate layers--the upper mixolimnion (with seasonal mixing) and the lower monimolimnion (without seasonal mixing). For the estimation of groundwater discharge rates into the lake, a simple box model including all radon sinks and sources related to each layer was applied. Two field investigations were performed. During the October campaign, the total groundwater discharge into the lake was found to be 18.9 and 0.7 m(3) d(-1) for the mixolimnion and monimolimnion, respectively. During the December campaign, the groundwater discharge into the mixolimnion was 15.0 m(3) d(-1), whereas no discharge at all was observed into the monimolimnion. Based on the given water volumes, the residence time of lake water was 5.3 years for the monimolimnion and varies between 0.9 and 1.1 years for the mixolimnion. The investigation confirmed radon to be a useful environmental tracer for groundwater and surface water interactions in meromictic lake environments.
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Ecology, physiology, and phylogeny of deep subsurface Sphingomonas sp.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fredrickson, Jim K.; Balkwill, David L.; Romine, Margaret F.
Several new species of the genus Sphingomonas including S. aromaticivorans, S. stygia, and S. subterranea that have the capacity for degrading a broad range of aromatic compounds including toluene, naphthalene, xylenes, p-cresol, fluorene, biphenyl, and dibenzothiophene, were isolated from deeply-buried (>200 m) sediments of the US Atlantic coastal plain (ACP). In S. aromaticivorans F199, many of the genes involved in the catabolism of these aromatic compounds are encoded on a 184-kb conjugative plasmid; some of the genes involved in aromatic catabolism are plasmid-encoded in the other strains as well. Members of the genus Sphingomonas were common among aerobic heterotrophic bacteriamore » cultured from ACP sediments and have been detected in deep subsurface environments elsewhere. The major source of organic carbon for heterotrophic metabolism in ACP deep aquifers is lignite that originated from plant material buried with the sediments. We speculate that the ability of the subsurface Sphingomonas strains to degrade a wide array of aromatic compounds represents an adaptation for utilization of sedimentary lignite. These and related subsurface Sphingomonas spp may play an important role in the transformation of sedimentary organic carbon in the aerobic and microaerobic regions of the deep aquifers of the ACP.« less
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Toxic emissions during co-combustion of biomass-waste wood-lignite blends in an industrial boiler.
Samaras, P; Skodras, G; Sakellaropoulos, G P; Blumenstock, M; Schramm, K W; Kettrup, A
2001-01-01
The objectives of this work were to study the PCDD/F emissions during the co-combustion of waste wood/coal co-combustion in an industrial boiler and to determine the relation of the toxic emissions to the fuel properties. Co-combustion experiments were performed in a 13.8 MWthermal industrial moving grate combustor. The fuels which were examined in this study included Greek lignite, natural uncontaminated wood, power poles and medium density fibers (MDFs) which were by-products of the plant production process. Fuel blends were prepared by mixing single components in various concentrations. PCDD/F emissions were collected during experimental runs and were analyzed according to standard methods. Low PCDD/F emissions were obtained during the co-combustion tests, lower than the limit value of 0.1 ng TEQ/Nm3. The lowest values were observed during the combustion of fuel blends containing MDF, possibly due to the inhibitory action of some of the N-containing MDF ingredients, such as urea. No direct correlation was found between the PCDD/F and the copper emissions, while examination of the PCDD/F homologue patterns revealed the predominance of the lower chlorinated isomers over the higher ones.
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Adsorption isotherms and kinetics of activated carbons produced from coals of different ranks.
Purevsuren, B; Lin, Chin-Jung; Davaajav, Y; Ariunaa, A; Batbileg, S; Avid, B; Jargalmaa, S; Huang, Yu; Liou, Sofia Ya-Hsuan
2015-01-01
Activated carbons (ACs) from six coals, ranging from low-rank lignite brown coal to high-rank stone coal, were utilized as adsorbents to remove basic methylene blue (MB) from an aqueous solution. The surface properties of the obtained ACs were characterized via thermal analysis, N2 isothermal sorption, scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and Boehm titration. As coal rank decreased, an increase in the heterogeneity of the pore structures and abundance of oxygen-containing functional groups increased MB coverage on its surface. The equilibrium data fitted well with the Langmuir model, and adsorption capacity of MB ranged from 51.8 to 344.8 mg g⁻¹. Good correlation coefficients were obtained using the intra-particle diffusion model, indicating that the adsorption of MB onto ACs is diffusion controlled. The values of the effective diffusion coefficient ranged from 0.61 × 10⁻¹⁰ to 7.1 × 10⁻¹⁰ m² s⁻¹, indicating that ACs from lower-rank coals have higher effective diffusivities. Among all the ACs obtained from selected coals, the AC from low-rank lignite brown coal was the most effective in removing MB from an aqueous solution.
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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.
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Ecology, physiology, and phylogeny of deep subsurface Sphingomonas sp.
Fredrickson, J K; Balkwill, D L; Romine, M F; Shi, T
1999-10-01
Several new species of the genus Sphingomonas including S. aromaticivorans, S. stygia, and S. subterranea that have the capacity for degrading a broad range of aromatic compounds including toluene, naphthalene, xylenes, p-cresol, fluorene, biphenyl, and dibenzothiophene, were isolated from deeply-buried (>200 m) sediments of the US Atlantic coastal plain (ACP). In S. aromaticivorans F199, many of the genes involved in the catabolism of these aromatic compounds are encoded on a 184-kb conjugative plasmid; some of the genes involved in aromatic catabolism are plasmid-encoded in the other strains as well. Members of the genus Sphingomonas were common among aerobic heterotrophic bacteria cultured from ACP sediments and have been detected in deep subsurface environments elsewhere. The major source of organic carbon for heterotrophic metabolism in ACP deep aquifers is lignite that originated from plant material buried with the sediments. We speculate that the ability of the subsurface Sphingomonas strains to degrade a wide array of aromatic compounds represents an adaptation for utilization of sedimentary lignite. These and related subsurface Sphingomonas spp may play an important role in the transformation of sedimentary organic carbon in the aerobic and microaerobic regions of the deep aquifers of the ACP.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Bozkurt, Y.; Misirlioglu, Z.; Sinag, A.
The reactivities of chars obtained by pyrolysis of Bursa Mustafa Kemal Pasa Alpagut lignite and Balkesir Dursunbey Cakiirca lignite (Turkey) at different temperatures were determined by CO{sub 2} gasification and by combustion with O{sub 2}. Catalytic effect of Na{sub 2}CO{sub 3} on the CO{sub 2} and O{sub 2} gasification reactivity of chars was investigated. Gasification tests were performed in the fixed bed reactors operating at ambient pressure. Reactivity of chars during the CO{sub 2} gasification reactions was determined by calculating the reaction rate constants and reactivity of chars during the O{sub 2} gasification was determined by using ignition temperatures ofmore » the samples. Activation energies and Arrhenius constants of the chars on the CO{sub 2} gasification reactions were also calculated by the help of Arrhenius curves. The activation energy for CO{sub 2} gasification was generally decreased with pyrolysis temperature, due to the different surface characteristics and different nature of carbon atoms gasified as the gasification reactions proceed. Generally, the increase in pyrolysis temperature leads to an increase in gasification reactivity with CO{sub 2}. The reactivity of chars in catalytic gasification was higher than the corresponding non-catalytic reactivity of the same chars. Ignition temperature increased with increasing pyrolysis temperature.« less
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Govindaraju, M; Ganeshkumar, R S; Muthukumaran, V R; Visvanathan, P
2012-05-01
Thermal power plants emit various gaseous and particulate pollutants into the atmosphere. It is well known that trees help to reduce air pollution. Development of a greenbelt with suitable plant species around the source of emission will mitigate the air pollution. Selection of suitable plant species for a greenbelt is very important. Present study evaluates different plant species around Neyveli thermal power plant by calculating the Air Pollution Tolerance Index (APTI) which is based on their significant biochemical parameters. Also Anticipated Performance Index (API) was calculated for these plant species by combining APTI values with other socio-economic and biological parameters. Based on these indices, the most appropriate plant species were identified for the development of a greenbelt around the thermal power plant to mitigate air pollution. Among the 30 different plant species evaluated, Mangifere indica L. was identified as keystone species which is coming under the excellent category. Ambient air quality parameters were correlated with the biochemical characteristics of plant leaves and significant changes were observed in the plants biochemical characteristics due to the air pollution stress.
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A novel way to upgrade the coarse part of a high calcium fly ash for reuse into cement systems.
Antiohos, S K; Tsimas, S
2007-01-01
Reject fly ash (rFA) represents a significant portion of the fly ashes produced from coal-fired power plants. Due to the high carbon content and large particle mean diameter, rFA is not utilized in the construction sector (for example, as supplementary cementing material) and is currently dumped into landfills, thus representing an additional environmental burden. Recently, the feasibility of using rFA in a relatively small number of applications, like solidification/stabilization of other wastes, has been investigated by different researchers. However, as the overall amount of fly ash utilized in such applications is still limited, there is a need to investigate other possibilities for rFA utilization starting from a deeper understanding of its properties. In the work presented herein, mechanical and hydration properties of cementitious materials prepared by blending the coarse fraction of a lignite high-calcium fly ash with ordinary cement were monitored and compared with the respective ones of a good quality fly ash-cement mixture. The results of this work reveal that a relatively cheap, bilateral classification-grinding method is able to promote the pozzolanic behavior of the rFAs, so that the overall performances of rFA containing cements are drastically improved. The evaluation of these results supports the belief that appropriate utilization of non-standardized materials may lead to new environmental-friendly products of superior quality.
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Coal-oil coprocessing at HTI - development and improvement of the technology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stalzer, R.H.; Lee, L.K.; Hu, J.
1995-12-31
Co-Processing refers to the combined processing of coal and petroleum-derived heavy oil feedstocks. The coal feedstocks used are those typically utilized in direct coal liquefaction: bituminous, subbituminous, and lignites. Petroleum-derived oil, is typically a petroleum residuum, containing at least 70 W% material boiling above 525{degrees}C. The combined coal and oil feedstocks are processed simultaneously with the dual objective of liquefying the coal and upgrading the petroleum-derived residuum to lower boiling (<525{degrees}C) premium products. HTI`s investigation of the Co-Processing technology has included work performed in laboratory, bench and PDU scale operations. The concept of co-processing technology is quite simple and amore » natural outgrowth of the work done with direct coal liquefaction. A 36 month program to evaluate new process concepts in coal-oil coprocessing at the bench-scale was begun in September 1994 and runs until September 1997. Included in this continuous bench-scale program are provisions to examine new improvements in areas such as: interstage product separation, feedstock concentrations (coal/oil), improved supported/dispersed catalysts, optimization of reactor temperature sequencing, and in-line hydrotreating. This does not preclude other ideas from DOE contracts and other sources that can lead to improved product quality and economics. This research work has led to important findings which significantly increased liquid yields, improved product quality, and improved process economics.« less
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Crowley, Sharon S.; Warwick, Peter D.; Ruppert, Leslie F.; Pontolillo, James
1997-01-01
The origin and distribution of twelve potentially Hazardous Air Pollutants (HAPs; As, Be, Cd, Cr, Co, Hg, Mn, Ni, Pb, Sb, Se, and U) identified in the 1990 Clean Air Act Amendments were examined in relation to the maceral composition of the A1 bed (Paleocene, Calvert Bluff Formation, Wilcox Group) of the Calvert mine in east-central Texas. The 3.2 m-thick A1 bed was divided into nine incremental channel samples (7 lignite samples and 2 shaley coal samples) on the basis of megascopic characteristics. Results indicate that As, Cd, Cr, Ni, Pb, Sb, and U are strongly correlated with ash yield and are enriched in the shaley coal samples. We infer that these elements are associated with inorganic constituents in the coal bed and may be derived from a penecontemporaneous stream channel located several kilometers southeast of the mining block. Of the HAPs elements studied, Mn and Hg are the most poorly correlated to ash yield. We infer an organic association for Mn; Hg may be associated with pyrite. The rest of the trace elements (Be, Co, and Se) are weakly correlated with ash yield. Further analytical work is necessary to determine the mode of occurrence for these elements. Overall, concentrations of the HAPs elements are generally similar to or less than those reported in previous studies of lignites of the Wilcox Group, east-central region, Texas. Petrographic analysis indicates the following ranges in composition for the seven lignite samples: liptinites (5–8%), huminites (88–95%), and inertinites (trace amounts to 7%). Samples from the middle portion of the A1 bed contain abundant crypto-eugelinite compared to the rest of the samples; this relationship suggests that the degradation of plant material was an important process during the development of the peat mire. With the exception of Hg and Mn, relatively low levels of the HAPs elements studied are found in the samples containing abundant crypto-eugelinite. We infer that the peat-forming environment for this portion of the coal bed was very wet with minimal detrital input. Relatively high concentrations of crypto-humotelinite were found in samples from the top and base of the coal bed. The presence of abundant crypto-humotefinite in this part of the coal bed suggests the accumulation of wood-rich peat under conditions conducive to a high degree of tissue preservation in the peat mire. Although several of the trace elements (Be, Co, Ni, and Sb) exhibit enrichment in these samples, they are not necessarily chemically associated with humotelinite. We infer that these elements, with the exception of Be, are possibly associated with deposition of the roof and floor rock of the coal bed; however, further analytical work would be necessary to confirm this hypothesis. Beryllium may have an organic origin.
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Zabala, Jabi; Zuberogoitia, Iñigo
2014-01-01
Evolution by natural selection depends on the relationship between individual traits and fitness. Variation in individual fitness can result from habitat (territory) quality and individual variation. Individual quality and specialization can have a deep impact on fitness, yet in most studies on territorial species the quality of territory and individuals are confused. We aimed to determine if variation in breeding success is better explained by territories, individual quality or a combination of both. We analysed the number of fledglings and the breeding quality index (the difference between the number of fledglings of an individual/breeding pair and the average number of fledglings of the monitored territories in the same year) as part of a long term (16 years) peregrine falcon (Falco peregrinus) monitoring program with identification of individuals. Using individual and territory identities as correlates of quality, we built Generalised Linear Models with Mixed effects, in which random factors depicted different hypotheses for sources of variation (territory/individual quality) in the reproductive success of unique breeding pairs, males and females, and assessed their performance. Most evidence supported the hypothesis that variation in breeding success is explained by individual identity, particularly male identity, rather than territory. There is also some evidence for inter year variations in the breeding success of females and a territory effect in the case of males. We argue that, in territorial species, individual quality is a major source of variation in breeding success, often masked by territory. Future ecological and conservation studies on habitat use should consider and include the effect of individuals, in order to avoid misleading results. PMID:24599280
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Nordey, Thibault; Léchaudel, Mathieu; Génard, Michel; Joas, Jacques
2014-11-01
Managing fruit quality is complex because many different attributes have to be taken into account, which are themselves subjected to spatial and temporal variations. Heterogeneous fruit quality has been assumed to be partly related to temperature and maturity gradients within the fruit. To test this assumption, we measured the spatial variability of certain mango fruit quality traits: colour of the peel and of the flesh, and sourness and sweetness, at different stages of fruit maturity using destructive methods as well as vis-NIR reflectance. The spatial variability of mango quality traits was compared to internal variations in thermal time, simulated by a physical model, and to internal variations in maturity, using ethylene content as an indicator. All the fruit quality indicators analysed showed significant spatial and temporal variations, regardless of the measurement method used. The heterogeneity of internal fruit quality traits was not correlated with the marked internal temperature gradient we modelled. However, variations in ethylene content revealed a strong internal maturity gradient which was correlated with the spatial variations in measured mango quality traits. Nonetheless, alone, the internal maturity gradient did not explain the variability of fruit quality traits, suggesting that other factors, such as gas, abscisic acid and water gradients, are also involved. Copyright © 2014 Elsevier GmbH. All rights reserved.
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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.
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40 CFR 74.23 - 1985 Allowable SO 2 emissions rate.
Code of Federal Regulations, 2013 CFR
2013-07-01
....00 1.00 Coal Unit with Federal Limit, but Averaging Time Not Specified 0.93 0.89 (2) Calendar year... Bituminous coal Subbituminous coal Lignite coal Oil lbs Sulfur/mmBtu 2.0 2.0 2.0 2.0 % Sulfur in fuel 1.66 2... year as defined under § 74.23(a)(2). (ii) Citation of statute, regulations, and any other authority...
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40 CFR 74.23 - 1985 Allowable SO 2 emissions rate.
Code of Federal Regulations, 2014 CFR
2014-07-01
....00 1.00 Coal Unit with Federal Limit, but Averaging Time Not Specified 0.93 0.89 (2) Calendar year... Bituminous coal Subbituminous coal Lignite coal Oil lbs Sulfur/mmBtu 2.0 2.0 2.0 2.0 % Sulfur in fuel 1.66 2... year as defined under § 74.23(a)(2). (ii) Citation of statute, regulations, and any other authority...
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Polish plant beats the odds to become model EU generator
DOE Office of Scientific and Technical Information (OSTI.GOV)
Neville, A.
2009-03-15
Once a Soviet satellite, Poland is now transforming into a thoroughly modern nation. To support its growing economy, this recent European Union member country is modernizing its power industry. Exemplifying the advances in the Polish electricity generation market is the 460 MW Patnow II power plant - the largest, most efficient (supercritical cycle) and environmentally cleanest lignite-fired unit in the country. 3 photos.
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NASA Astrophysics Data System (ADS)
Popescu, S.-M.; Suc, J.-P.; Loutre, M. F.
High-resolution pollen analyses on the lignite-clay Lupoaia section (from 4.9 to 4.3 Ma) in southwestern Romania provide an accurate record of the Lower Pliocene veg- etation changes in the Danube paleodelta environment close to the Carpathians. Many major fluctuations concern thermophilous trees vs. altitudinal trees (chiefly in agree- ment with lignite-clay alternations) and have been referred to changes in temperature. Thanks to a reliable magnetostratigraphic calibration of the section, such changes are to be linked to eccentricity cycles, that provides a more precise chronologic control to the section (Popescu, in press). In addition, regular secondary fluctuations occur which oppose swamp trees (such as most of the Taxodiaceae) to marsh herbs (such as Cyperaceae). They evoke the present-day landscape of the Mississippi delta where swamp forests (constituted by Taxodium distichum mainly) are in competition with herbaceous marshes (made of Cyperaceae such as Mariscus jamaicensis in addition to some Cyrillaceae and Myrica). The latest require significantly more water than the swamps (Roberts, 1986). These plant environments cause two kinds of lignite deposition that have been also identified in the Lupoaia section (Ticleanu and Dia- conita, 1997). According to the chronologic frame previously defined, it is possible to evidence a precession forcing for these alternations. Minima in precession probably caused increasing rainfall over the region and expansion of marshes. So, it is sug- gested that during Lower Pliocene the West Asian monsoon influenced climate of the northeastern Mediterranean region. References. Popescu, S.-M., in press. Repetitive changes in Lower Pliocene vegetation revealed by high-resolution pollen analysis: revised cyclostratigraphy of Southwest- ern Romania. Rev. Palaeobot. Palynol. Roberts, H.H., 1986. Selected depositional en- vironments of the Mississippi River deltaic plain. Geol. Sc. America Centennial Field Guide-Southeastern Section, 98, 435-440. Ticleanu, N. and Diaconita, D., 1997. The main coal facies and lithotypes of the Pliocene coal basin, Oltenia, Romania. In SEuro- & cedil;pean Coal Geology and TechnologyT, Gayer, R. and Peek, J. eds., Geological Society Special Publ., 125, 131-139.
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NASA Astrophysics Data System (ADS)
Ijiri, A.; Inagaki, F.
2015-12-01
During the Integrated Ocean Drilling Program (IODP) Expedition 337 in 2012, the riser-drilling vessel Chikyu extended the previous world depth record of scientific ocean drilling and made one of the deepest scientific borehole down to 2466 m below the seafloor (mbsf) at Site C0020 Hole A off the Shimokita Peninsula, Japan. The sedimentary sequence consists of 17 lignite layers below 1.5 km bellow the seafloor. Microbiological and geochemical data consistently showed evidence for the existence of microbial communities associated with lignite coal beds in the coal-bearing sediments (Inagaki and Hinrichs et al., Science, 2015). Since lignite coals produce substantial dissolved organic compounds during the burial alternation process, volatile fatty acids may play important roles for microbial life and its activity in the deep sedimentary environment. To address this hypothesis, we measured methanogenic and acetate-oxidation activities by radiotracer incubation experiments using 14C-labelled substrate ([2-14C]-acetate) immediately after core recovery. Activity of aceticlastic methanogenesis was observed in the sediment above the coal-baring layers (>1990 mbsf), ranging from 0.2 to 1.2 pmol cm-3 d-1. The highest activity was observed in a coal-bed horizon at 1990 mbsf. However, aceticlastic methanogenesis was below the detection limit in sediment samples below the 2 km-coal layers. Activity of acetate oxidation to CO2 was measured by 14CO2 production rate from [2-14C]-acetate. Interestingly, the acetate-oxidation activity was observed in sediments above the coal beds, which values were generally higher than those of methanogenesis with the maximum value of 33 pmol cm-3 d-1 at 1800 mbsf. The rates gradually decreased with increasing depth from 1800 mbsf and reached below the detection limit (i.e., 0.05 pmol cm-3 d-1) in 2 km-deep coal-bed samples. The occurrence of relatively high acetate oxidation at ~1800 mbsf above the coal formation suggests that microbes respire acetate with available electron acceptors such as glauconitic iron oxides in the deep sedimentary environment.
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NASA Astrophysics Data System (ADS)
Bouchal, Johannes Martin; Güner, Tuncay H.; Denk, Thomas
2015-04-01
The subject of this study is the palynology (biostratigraphic and taxonomic) and the plant remains of the lignite strip mines of Eskihisar, Salihpasalar, and Tinaz (Muğla province, western Turkey). In the Yatağan basin two Miocene to Pliocene formations are present, the Eskihisar Formation (early to middle Miocene) and the Yatağan Formation (late Miocene to early Pliocene). Both formations represent river and lake deposits consisting mainly of conglomerate, sandstone, claystone, limestone, tuffite, and intercalated lignite; the thickest, actively mined lignite seams occur in the Sekköy member of the Eskihisar Formation. Previous palynological studies of the palynoflora of the Yatağan basin mainly focussed on its biostratigraphic and palaeoclimatic significance, using conventional morphological nomenclature and light microscopy (LM). In this study the "single grain method" is applied. Using this method, the same individual pollen grains are investigated by using both LM and scanning electron microscopy (SEM). The resulting high-resolution pictographs enable a much higher taxonomic resolution. The studied palynoflora is very rich and taxonomically diverse. Cryptogams are represented by more than ten spore morphotypes of at least three families (Osmundaceae, Pteridaceae, Polypodiaceae). Gymnosperm pollen is dominated by Cupressaceae, Gnetales (Ephedra), and Pinaceae (Cathaya, Keteleeria, Pinus). Angiosperm pollen can be assigned to 57 different genera belonging to Poaceae, Typhaceae, Altingiaceae, Amaranthaceae (Chenopodieae), Anacardiaceae, Apiaceae (three types), Asteraceae (Asteroideae, Cichoriodeae), Betulaceae (Alnus, Betula, Carpinus, Ostrya) Buxaceae, Campanulaceae, Caprifoliaceae (Lonicera), Caryophyllaceae, Dipsacaceae, Eucommiaceae, Euphorbiaceae, Fabaceae, Fagaceae (Fagus, Quercus, Trigonobalanopsis) Geraniaceae, Juglandaceae, Linaceae, Malvaceae (Tilia), Myricaceae, Oleaceae (four different types), Plumbaginaceae, Polygonaceae (Rumex), Rosaceae, Sapindaceae (Acer), Ulmaceae (Cedrelospermum, Ulmus, Zelkova), and Zingiberales (Spirematospermum). In addition, more than two thousand plant macrofossils were collected in the course of repeated field trips, including remains of Pinaceae, Berberidiaceae (Mahonia), Betulaceae (Alnus, Carpinus), Buxaceae (Buxus), Fagaceae (Fagus, Quercus), Lauraceae, Malvaceae (Tilia), Myricaceae (Myrica), Rosaceae, Salicaceae (Populus, Salix), Sapindaceae (Acer), Smilacaceae (Smilax), Typhaceae (Typha), Ulmaceae (Zelkova). A combined analysis integrating these rich and diverse plant macro- and microfossil records will lead to a better understanding and refined reconstruction of the vegetation in the Yatağan basin during the middle to late Miocene.
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Alvarez, Juan B; Guzmán, Carlos
2018-02-01
The hybridization events with wild relatives and old varieties are an alternative source for enlarging the wheat quality variability. This review describes these process and their effects on the technological and nutritional quality. Wheat quality and its end-uses are mainly based on variation in three traits: grain hardness, gluten quality and starch. In recent times, the importance of nutritional quality and health-related aspects has increased the range of these traits with the inclusion of other grain components such as vitamins, fibre and micronutrients. One option to enlarge the genetic variability in wheat for all these components has been the use of wild relatives, together with underutilised or neglected wheat varieties or species. In the current review, we summarise the role of each grain component in relation to grain quality, their variation in modern wheat and the alternative sources in which wheat breeders have found novel variation.
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Comprehensive Fractal Description of Porosity of Coal of Different Ranks
Ren, Jiangang; Zhang, Guocheng; Song, Zhimin; Liu, Gaofeng; Li, Bing
2014-01-01
We selected, as the objects of our research, lignite from the Beizao Mine, gas coal from the Caiyuan Mine, coking coal from the Xiqu Mine, and anthracite from the Guhanshan Mine. We used the mercury intrusion method and the low-temperature liquid nitrogen adsorption method to analyze the structure and shape of the coal pores and calculated the fractal dimensions of different aperture segments in the coal. The experimental results show that the fractal dimension of the aperture segment of lignite, gas coal, and coking coal with an aperture of greater than or equal to 10 nm, as well as the fractal dimension of the aperture segment of anthracite with an aperture of greater than or equal to 100 nm, can be calculated using the mercury intrusion method; the fractal dimension of the coal pore, with an aperture range between 2.03 nm and 361.14 nm, can be calculated using the liquid nitrogen adsorption method, of which the fractal dimensions bounded by apertures of 10 nm and 100 nm are different. Based on these findings, we defined and calculated the comprehensive fractal dimensions of the coal pores and achieved the unity of fractal dimensions for full apertures of coal pores, thereby facilitating, overall characterization for the heterogeneity of the coal pore structure. PMID:24955407
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NASA Astrophysics Data System (ADS)
Ciesłik, Tobiasz; Górniak-Zimroz, Justyna
2018-01-01
Opencast mining of large-area lignite deposits impacts the environment, and the health and life of people living in the vicinity of the conducted mining activity. Therefore, the attempt was made to develop a methodology for identification of environmental and social changes in the Bogatynia municipality (south-western Poland), resulting from functioning of Turow lignite mine within its area. During the study of changes occurring over the years, the development of mining pit was noticed, as well as the transformations of this area and impact of the mining plant on the selected elements of environment and surrounding areas. Analogue and digital data were used for the preparation of cartographic compilations, the usefulness of which was analyzed in accordance with the guidelines contained in the standard [1]. The conducted cartographic studies allowed to learn the history of the mine together with identification of changes taking place in the municipality Bogatynia. The obtained results show the form and condition of the objects in the analyzed year, allowing for the interpretation of changes that occurred in the surrounding areas of the Turow mine. Due to the conducted activity of the mine and Turow power plant, both negative and positive aspects were noted in connection with the carrying out of mining activity in the Bogatynia municipality.
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Sod-seeding to modify coastal bermuda grass on reclaimed lignite overburden in Texas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Skousen, J.G.
1986-01-01
This study was conducted to investigate the ability of nine low-maintenance species to establish and persist with Coastal bermuda grass (Cynodon dactylon (L.) Pers.) established on reclaimed lignite overburden; to evaluate the establishment and persistence of seventeen low-maintenance species seeded in overburden with no vegetation cover; and to examine seeding mixtures and rates for establishing low-maintenance species into three cover types (bermuda grass, oats, (Avena fatua L.) and no cover). Seventeen low-maintenance species established and persisted in overburden without fertilization during years of low precipitation. Several seeded grasses showed sufficient stand development in monoculture for erosion control. Most of themore » other seeded species were slower in establishment, yet persisted on the site and promoted multiple use of the reclaimed area. Recommended seeding rates were generally adequate for seedling establishment in oat, bermuda grass, and no vegetation cover types. Sod-seeding into bermuda grass resulted in higher seedling densities than those in oats and no cover because of stored moisture beneath the sod during bermuda grass dormancy. Using /sup 15/N-labelled fertilizer, Coastal bermuda grass demonstrated the ability to rapidly recovery applied N. Maximilian sunflower (Helianthus maximiliani Schrad.) was suppressed by Coastal bermuda grass in mixture at all fertilizer N rates.« less
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Samouhos, Michail; Taxiarchou, Maria; Tsakiridis, Petros E; Potiriadis, Konstantinos
2013-06-15
The present research work is focused on the development of an alternative microwave reductive roasting process of red mud using lignite (30.15 wt.%Cfix), followed by wet magnetic separation, in order to produce a raw material suitable for sponge or cast iron production. The reduction degree of iron was controlled by both the reductive agent content and the microwave heating time. The reduction followed the Fe₂O₃ → Fe₃O₄ → FeO → Fe sequence. The dielectric constants [real (ε') and imaginary (ε″) permittivities] of red mud-lignite mixture were determined at 2.45 GHz, in the temperature range of 25-1100 °C. The effect of parameters such as temperature, intensity of reducing conditions, intensity of magnetic field and dispersing agent addition rate on the result of both processes was investigated. The phase's transformations in reduction process with microwave heating were determined by X-ray diffraction analysis (XRD) in combination with thermogravimetric/differential thermal analysis (TGA/DTA). The microstructural and morphological characterization of the produced calcines was carried out by scanning electron microscopy (SEM). At the optimum conditions a magnetic concentrate with total iron concentration of 35.15 and 69.3 wt.% metallization degree was obtained. Copyright © 2013 Elsevier B.V. All rights reserved.
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Coal deposits of the United States
John, Nelson W.
1987-01-01
The coal fields of the Unites States can be divided into six major provinces. The Appalachian and Interior Provinces contain dominantly bituminous coal in strata of Pennsylvanian age. The coal seams are relatively thin and are mined both by surface and underground methods. Sulfyur content is low to moderate in the Appalachian Province, generally high in the Interior province. The Gulf Coastal Plain Province, in Texas and neighboring states, contains lignite of Eocene age. The seams are 3-25 ft (0.9-7.5 m) thick and are minded in large open pits. The Northern Great Plains Province has lignite and subbituminous coal of Cretaceous, Paleocene and Eocene age. The coal, largely very low in sulfur, occurs in beds up to 100 ft (30 m) thick and is strip-mined. The Rocky Mountain Province contains a great variety of coal deposits in numerous separate intermontane basins. Most of it is low-sulfur subbituminous to bituminous coal iof Creatceous and early Tertiary age. The seams range from a few feet to over 100 ft (30 m) thick. Strip-mining dominates but underground mines are important in Utah and Colorado. The Pacific Coast Province, which includes Alaska, contains enormous cola resources but has seen little mining. The coal is highly diverse in physical character and geologic setting. ?? 1987.
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Bucket wheel rehabilitation of ERC 1400-30/7 high-capacity excavators from lignite quarries
NASA Astrophysics Data System (ADS)
Vîlceanu, Fl; Iancu, C.
2016-11-01
The existence of bucket wheel equipment type ERC 1400-30/7 in lignite quarries with lifetime expired, or in the ultimate life period, together with high cost investments for their replacement, makes rational the efforts made to rehabilitation in order to extend their life. Rehabilitation involves checking operational safety based on relevant expertise of metal structures supporting effective resistance but also the replacement (or modernization) of subassemblies that can increase excavation process productivity, lowering energy consumption, reducing mechanical stresses. This paper proposes an analysis of constructive solution of using a part of the classical bucket wheel, on which are located 9 cutting cups and 9 chargers cups and adding a new part so that the new redesigned bucket-wheel will contain 18 cutting-chargers cups, compared to the classical model. On the CAD model of bucket wheel was performed a static and a dynamic FEA, the results being compared with the yield strength of the material of the entire structure, were checked mechanical stresses in the overall distribution map, and were verified the first 4 vibrating modes the structure compared to real loads. Thus was verified that the redesigned bucket-wheel can accomplish the proposed goals respectively increase excavation process productivity, lowering energy consumption and reducing mechanical stresses.
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Lead isotope ratios in tree bark pockets: an indicator of past air pollution in the Czech Republic.
Conkova, M; Kubiznakova, J
2008-10-15
Tree bark pockets were collected at four sites in the Czech Republic with differing levels of lead (Pb) pollution. The samples, spanning 1923-2005, were separated from beech (Fagus sylvatica) and spruce (Picea abies). Elevated Pb content (0.1-42.4 microg g(-1)) reflected air pollution in the city of Prague. The lowest Pb content (0.3-2.6 microg g(-1)) was found at the Kosetice EMEP "background pollution" site. Changes in (206)Pb/(207)Pb and (208)Pb/(206)Pb isotope ratios were in agreement with operation times of the Czech main anthropogenic Pb sources. Shortly after the Second World War, the (206)Pb/(207)Pb isotope ratio in bark pockets decreased from 1.17 to 1.14 and the (208)Pb/(206)Pb isotope ratio increased from 2.12 to 2.16. Two dominant emission sources responsible for these changes, lignite and leaded petrol combustion, contributed to the shifts in Pb isotope ratios. Low-radiogenic petrol Pb ((206)Pb/(207)Pb of 1.11) lead to lower (206)Pb/(207)Pb in bark pockets over time. High-radiogenic lignite-derived Pb ((206)Pb/(207)Pb of 1.18 to 1.19) was detected in areas affected by coal combustion rather than by traffic.
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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
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Beroni, E.P.; McKeown, F.A.
1952-01-01
Previous discoveries and studies of radioactive lignites of Tertiary age in North Dakota, South Dakota, Montana, and Wyoming led the Geological Survey in 1950 to do reconnaissance in the Green River and Uinta Basin of Wyoming and Utah, where similar lignites were believed to be present. Because of the common association of uranium with copper deposits and the presence of such deposits in the Uinta Basin, several areas containing copper-uranium minerals were also examined. No deposits commercially exploitable under present conditions were found. Samples of coal from the Bear River formation at Sage, Wyo., assayed 0.004 to 0.013 percent uranium in the ash; in the old Uteland copper mine in Uinta County, Utah, 0.007 to 0.017 percent uranium; in a freshwater limestone, Duchesne County, Utah, as much as 0.019 percent uranium; and in the Mesaverde formation at the Snow and Bonniebell claims near Jensen, Uintah County, Utah, 0.003 to 0.090 percent uranium. Maps were made and samples were taken at the Skull Creek carnotite deposits in Moffat County, Colo. (0.006 to 0.16 percent uranium); at the Fair-U claims in Routt County, Colo. (0.002 to 0.040 percent uranium); and at the Lucky Strike claims near Kremmling in Grand County, Colo. (0.006 to 0.018 percent uranium).
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Reactivity of alkaline lignite fly ashes towards CO{sub 2} in water
DOE Office of Scientific and Technical Information (OSTI.GOV)
Martin Back; Michael Kuehn; Helge Stanjek
2008-06-15
The reaction kinetics between alkaline lignite fly ashes and CO{sub 2} (pCO{sub 2} = 0.01-0.03 MPa) were studied in a laboratory CO{sub 2} flow-through reactor at 25-75{sup o}C. The reaction is characterized by three phases that can be separated according to the predominating buffering systems and the rates of CO{sub 2} uptake. Phase I (pH > 12, < 30 min) is characterized by the dissolution of lime, the onset of calcite precipitation and a maximum uptake, the rate of which seems to be limited by dissolution of CO{sub 2}. Phase II (pH < 10.5, 10-60 min) is dominated by themore » carbonation reaction. CO{sub 2} uptake in phase III (pH < 8.3) is controlled by the dissolution of periclase (MgO) leading to the formation of dissolved magnesium-bicarbonate. Phase I could be significantly extended by increasing the solid-liquid ratios and temperature, respectively. At 75{sup o}C the rate of calcite precipitation was doubled leading to the neutralization of approximately 0.23 kg CO{sub 2} per kg fly ash within 4.5 h, which corresponds to nearly 90% of the total acid neutralizing capacity. 21 refs., 5 figs., 1 tab.« less
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Olea, R.A.; Luppens, J.A.; Tewalt, S.J.
2011-01-01
A common practice for characterizing uncertainty in coal resource assessments has been the itemization of tonnage at the mining unit level and the classification of such units according to distance to drilling holes. Distance criteria, such as those used in U.S. Geological Survey Circular 891, are still widely used for public disclosure. A major deficiency of distance methods is that they do not provide a quantitative measure of uncertainty. Additionally, relying on distance between data points alone does not take into consideration other factors known to have an influence on uncertainty, such as spatial correlation, type of probability distribution followed by the data, geological discontinuities, and boundary of the deposit. Several geostatistical methods have been combined to formulate a quantitative characterization for appraising uncertainty. Drill hole datasets ranging from widespread exploration drilling to detailed development drilling from a lignite deposit in Texas were used to illustrate the modeling. The results show that distance to the nearest drill hole is almost completely unrelated to uncertainty, which confirms the inadequacy of characterizing uncertainty based solely on a simple classification of resources by distance classes. The more complex statistical methods used in this study quantify uncertainty and show good agreement between confidence intervals in the uncertainty predictions and data from additional drilling. ?? 2010.
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Methodology of selecting dozers for lignite open pit mines in Serbia
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stojanovic, D.; Ignjatovic, D.; Kovacevic, S.
1996-12-31
Apart from the main production processes (coal and overburden mining, rail conveyors transportation and storage of excavated masses) performed by great-capacity mechanization at open pit mines, numerous and different auxiliary works, that often have crucial influence on both the work efficiency of main equipment and the maintenance of optimum technical conditions of machines and plants covering technological system of open pit, are present. Successful realization of work indispensably requires a proper and adequate selection of auxiliary machines according to their type quantity, capacity, power etc. thus highly respecting specific conditions existing at each and every open pit mine. A dozermore » is certainly the most important and representative auxiliary machine at single open pit mine. It is widely used in numerous works that, in fact, are preconditions for successful work of the main mechanization and consequently the very selection of a dozer ranges among the most important operations when selecting mechanization. This paper presents the methodology of dozers selection when lignite open pit mines are concerned. A mathematical model defining the volume of work required for dozers to perform at open pit mines and consequently the number of necessary dozers was designed. The model underwent testing in practice at big open pit mines and can be used in design of future open pits mines.« less
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Multi-isotope tracing of CO2 leakage and water-rock interaction in a natural CCS analogue.
NASA Astrophysics Data System (ADS)
Kloppmann, Wolfram; Gemeni, Vasiliki; Lions, Julie; Koukouzas, Nikolaos; Humez, Pauline; Vasilatos, Charalampos; Millot, Romain; Pauwels, Hélène
2015-04-01
Natural analogues of CO2 accumulation and, potentially, leakage, provide a highly valuable opportunity to study (1) geochemical processes within a CO2-reservoir and the overlying aquifers or aquicludes, i.e. gas-water-rock interactions, (2) geology and tightness of reservoirs over geological timescales, (3) potential or real leakage pathways, (3) impact of leakage on shallow groundwater resources quality, and (4) direct and indirect geochemical indicators of gas leakage (Lions et al., 2014, Humez et al., 2014). The Florina Basin in NW Macedonia, Greece, contains a deep CO2-rich aquifer within a graben structure. The graben filling consists of highly heterogeneous Neogene clastic sediments constituted by components from the adjacent massifs including carbonates, schists, gneiss as well as some ultramafic volcanic rocks. Clay layers are observed that isolate hydraulically the deep, partly artesian aquifer. Organic matter, in form of lignite accumulations, is abundant in the Neogene series. The underlying bedrocks are metamorphic carbonates and silicate rocks. The origin of the CO2 accumulation is controversial (deep, partially mantle-derived D'Allessandro et al., 2008 or resulting from thermal decomposition of carbonates, Hatziyannis and Arvanitis, 2011). Groundwaters have been sampled from springs and borewells over 3 years at different depths. First results on major, minor and trace elements give evidence of water-rock interaction, mainly with carbonates but also with ultramafic components but do not indicate that CO2-seepage is the principal driver of those processes (Gemeni et al., submitted). Here we present isotope data on a selection of groundwaters (δ2H , δ18O, δ13CTDIC, 87Sr/86Sr, δ11B, δ7Li). Stable isotopes of water indicate paleo-recharge for some of the groundwaters, limited exchange with gaseous CO2 and, in one case, possibly thermal exchange processes with silicates. Sr isotope ratios vary between marine ratios and radiogenic values indicating interaction with carbonates and silicates. Both δ11B and δ7Li show a very large range of variation and fairly good correlation, between -29.7 o and +24o vs. NBS951 for boron and -11o and +20.4o vs. L-SVEC for lithium. The negative δ11B and δ7Li values are among the lowest reported in literature for groundwaters, comparable only to values observed for boron in case of geothermal fluids interaction with clay minerals (Pennisi et al., 2009) or in some amphiboles (e.g. Gillis et al., 2003) or lithium in ultramafic rocks (Nishio et al., 2004). Those variations reflect water-rock interaction with the silicate fraction of the highly heterogeneous graben filling but no clear indication of enhanced reactions due to CO2 intrusion has been found. The δ13C values of TDIC are also strongly variable (-10.5 to +15 o vs. PDB), reflecting biogenic inputs (e.g. from lignite layers), dissolution of carbonates and, potentially, methanogenesis through CO2 reduction. D' Alessandro W., Bellomo S., Brusca L., Karakazanis S., Kyriakopoulos K., and Liotta M. (2011) The impact on water quality of the high carbon dioxide contents of the groundwater in the area of Florina (N. Greece), Advances in the Research of Aquatic Environment. Springer. Gillis K. M., Coogan L. A., and Chaussidon M. (2003) Volatile element (B, Cl, F) behaviour in the roof of an axial magma chamber from the East Pacific Rise. Earth and Planetary Science Letters 213, 447-462. Hatziyannis G. and Arvanitits A. (2011) Natural analogues of CO2 leakage in Florina area, N. Greece., 2nd CGS Europe Knowledge Sharing Workshop Natural Analogues, Maria Laach, Germany, October 17-19, 2011, pp. Humez P., Negrel P., Lagneau V., Lions J., Kloppmann W., Gal F., Millot R., Guerrot C., Flehoc C., Widory D., and Girard J. F. (2014) CO2-water-mineral reactions during CO2 leakage: Geochemical and isotopic monitoring of a CO2 injection field test. Chem. Geol. 368, 11-30. Lions J., Humez P., Pauwels H., Kloppmann W., and Czernichowski-Lauriol I. (2014) Tracking leakage from a natural CO2 reservoir (Montmiral, France) through the chemistry and isotope signatures of shallow groundwater. Greenhouse Gases-Science and Technology 4, 225-243. Pennisi M., Bianchini G., Kloppmann W., and Muti A. (2009) Chemical and isotopic (B, Sr) composition of alluvial sediments as archive of a past hydrothermal outflow. Chem. Geol. 266, 123-134. Gemeni V., Vasilatos C., Koukouzas N., Kanellopoulos C. (submitted) Factors controlling the chemistry of the groundwater in a CO2 natural field: The case of Florina Basin, W. Macedonia, Greece. Submitted to Appl. Geochem.
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Make no mistake—errors can be controlled*
Hinckley, C
2003-01-01
Traditional quality control methods identify "variation" as the enemy. However, the control of variation by itself can never achieve the remarkably low non-conformance rates of world class quality leaders. Because the control of variation does not achieve the highest levels of quality, an inordinate focus on these techniques obscures key quality improvement opportunities and results in unnecessary pain and suffering for patients, and embarrassment, litigation, and loss of revenue for healthcare providers. Recent experience has shown that mistakes are the most common cause of problems in health care as well as in other industrial environments. Excessive product and process complexity contributes to both excessive variation and unnecessary mistakes. The best methods for controlling variation, mistakes, and complexity are each a form of mistake proofing. Using these mistake proofing techniques, virtually every mistake and non-conformance can be controlled at a fraction of the cost of traditional quality control methods. PMID:14532368
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Bray, Benjamin D; Cloud, Geoffrey C; James, Martin A; Hemingway, Harry; Paley, Lizz; Stewart, Kevin; Tyrrell, Pippa J; Wolfe, Charles D A; Rudd, Anthony G
2016-07-09
Studies in many health systems have shown evidence of poorer quality health care for patients admitted on weekends or overnight than for those admitted during the week (the so-called weekend effect). We postulated that variation in quality was dependent on not only day, but also time, of admission, and aimed to describe the pattern and magnitude of variation in the quality of acute stroke care across the entire week. We did this nationwide, registry-based, prospective cohort study using data from the Sentinel Stroke National Audit Programme. We included all adult patients (aged >16 years) admitted to hospital with acute stroke (ischaemic or primary intracerebral haemorrhage) in England and Wales between April 1, 2013, and March 31, 2014. Our outcome measure was 30 day post-admission survival. We estimated adjusted odds ratios for 13 indicators of acute stroke-care quality by fitting multilevel multivariable regression models across 42 4-h time periods per week. The study cohort comprised 74,307 patients with acute stroke admitted to 199 hospitals. Care quality varied across the entire week, not only between weekends and weekdays, with different quality measures showing different patterns and magnitudes of temporal variation. We identified four patterns of variation: a diurnal pattern (thrombolysis, brain scan within 12 h, brain scan within 1 h, dysphagia screening), a day of the week pattern (stroke physician assessment, nurse assessment, physiotherapy, occupational therapy, and assessment of communication and swallowing by a speech and language therapist), an off-hours pattern (door-to-needle time for thrombolysis), and a flow pattern whereby quality changed sequentially across days (stroke-unit admission within 4 h). The largest magnitude of variation was for door-to-needle time within 60 min (range in quality 35-66% [16/46-232/350]; coefficient of variation 18·2). There was no difference in 30 day survival between weekends and weekdays (adjusted odds ratio 1·03, 95% CI 0·95-1·13), but patients admitted overnight on weekdays had lower odds of survival (0·90, 0·82-0·99). The weekend effect is a simplification, and just one of several patterns of weekly variation occurring in the quality of stroke care. Weekly variation should be further investigated in other health-care settings, and quality improvement should focus on reducing temporal variation in quality and not only the weekend effect. None. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Method for Location of An External Dump in Surface Mining Using the A-Star Algorithm
NASA Astrophysics Data System (ADS)
Zajączkowski, Maciej; Kasztelewicz, Zbigniew; Sikora, Mateusz
2014-10-01
The construction of a surface mine always involves the necessity of accessing deposits through the removal of the residual overburden above. In the beginning phase of exploitation, the masses of overburden are located outside the perimeters of the excavation site, on the external dump, until the moment of internal dumping. In the case of lignite surface mines, these dumps can cover a ground surface of several dozen to a few thousand hectares. This results from a high concentration of lignite extraction, counted in millions of Mg per year, and the relatively large depth of its residual deposits. Determining the best place for the location of an external dump requires a detailed analysis of existing options, followed by a choice of the most favorable one. This article, using the case study of an open-cast lignite mine, presents the selection method for an external dump location based on graph theory and the A-star algorithm. This algorithm, based on the spatial distribution of individual intersections on the graph, seeks specified graph states, continually expanding them with additional elementary fields until the required surface area for the external dump - defined by the lowest value of the occupied site - is achieved. To do this, it is necessary to accurately identify the factors affecting the choice of dump location. On such a basis, it is then possible to specify the target function, which reflects the individual costs of dump construction on a given site. This is discussed further in chapter 3. The area of potential dump location has been divided into elementary fields, each represented by a corresponding geometrical locus. Ascribed to this locus, in addition to its geodesic coordinates, are the appropriate attributes reflecting the degree of development of its elementary field. These tasks can be carried out automatically thanks to the integration of the method with the system of geospatial data management for the given area. The collection of loci, together with geodesic coordinates, constitutes the points on the graph used during exploration. This is done using the A-star algorithm, which uses a heuristic function, allowing it to identify the optimal solution; therefore, the collection of elementary fields, which occupy the potential construction area of a dump, characterized by the lowest value representing the cost of occupation and dumping of overburden in the area. The precision of the boundary, generated by the algorithm, is dependent on the established size of the elementary field, and should be refined each time by the designer of the surface mine. This article presents the application of the above method of dump location using the example of "Tomisławice," a lignite surface mine owned by PAK KWB Konin S. A. The method made it possible to identify the most favorable dump location on the northeast side of the initial pit, within 2 kilometers of its surrounding area (discussed further in chapter 3). This method is universal in nature and, after certain modifications, can be implemented for other surface mines as well.
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Argyropoulos, G; Grigoratos, Th; Voutsinas, M; Samara, C
2013-10-01
Ambient concentrations of PM10 and associated elemental and ionic species were measured over the cold and the warm months of 2010 at an urban and two rural sites located in the lignite-fired power generation area of Megalopolis in Peloponnese, southern Greece. The PM10 concentrations at the urban site (44.2 ± 33.6 μg m(-3)) were significantly higher than those at the rural sites (23.7 ± 20.4 and 22.7 ± 26.9 μg m(-3)). Source apportionment of PM10 and associated components was accomplished by an advanced computational procedure, the robotic chemical mass balance model (RCMB), using chemical profiles for a variety of local fugitive dust sources (power plant fly ash, flue gas desulfurization wet ash, feeding lignite, infertile material from the opencast mines, paved and unpaved road dusts, soil), which were resuspended and sampled through a PM10 inlet onto filters and then chemically analyzed, as well as of other common sources such as vehicular traffic, residential oil combustion, biomass burning, uncontrolled waste burning, marine aerosol, and secondary aerosol formation. Geological dusts (road/soil dust) were found to be major PM10 contributors in both the cold and warm periods of the year, with average annual contribution of 32.6 % at the urban site vs. 22.0 and 29.0 % at the rural sites. Secondary aerosol also appeared to be a significant source, contributing 22.1 % at the urban site in comparison to 30.6 and 28.7 % at the rural sites. At all sites, the contribution of biomass burning was most significant in winter (28.2 % at the urban site vs. 14.6 and 24.6 % at the rural sites), whereas vehicular exhaust contribution appeared to be important mostly in the summer (21.9 % at the urban site vs. 11.5 and 10.5 % at the rural sites). The highest contribution of fly ash (33.2 %) was found at the rural site located to the north of the power plants during wintertime, when winds are favorable. In the warm period, the highest contribution of fly ash was found at the rural site located to the south of the power plants, although it was less important (7.2 %). Moderate contributions of fly ash were found at the urban site (5.4 and 2.7 % in the cold and the warm period, respectively). Finally, the mine field was identified as a minor PM10 source, occasionally contributing with lignite dust and/or deposited wet ash dust under dry summer conditions, with the summertime contributions ranging between 3.1 and 11.0 % among the three sites. The non-parametric bootstrapped potential source contribution function analysis was further applied to localize the regions of sources apportioned by the RCMB. For the majority of sources, source regions appeared as being located within short distances from the sampling sites (within the Peloponnesse Peninsula). More distant Greek areas of the NNE sector also appeared to be source regions for traffic emissions and secondary calcium sulfate dust.
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NASA Astrophysics Data System (ADS)
Khatami Firoozabadi, Seyed Reza
This work studied the ignition and combustion of burning pulverized coals and biomasses particles under either conventional combustion in air or oxy-fuel combustion conditions. Oxy-fuel combustion is a 'clean-coal' process that takes place in O2/CO2 environments, which are achieved by removing nitrogen from the intake gases and recirculating large amounts of flue gases to the boiler. Removal of nitrogen from the combustion gases generates a high CO2-content, sequestration-ready gas at the boiler effluent. Flue gas recirculation moderates the high temperatures caused by the elevated oxygen partial pressure in the boiler. In this study, combustion of the fuels took place in a laboratory laminar-flow drop-tube furnace (DTF), electrically-heated to 1400 K, in environments containing various mole fractions of oxygen in either nitrogen or carbon-dioxide background gases. The experiments were conducted at two different gas conditions inside the furnace: (a) quiescent gas condition (i.e., no flow or inactive flow) and, (b) an active gas flow condition in both the injector and furnace. Eight coals from different ranks (anthracite, semi-snthracite, three bituminous, subbituminous and two lignites) and four biomasses from different sources were utilized in this work to study the ignition and combustion characteristics of solid fuels in O2/N2 or O2/CO2 environments. The main objective is to study the effect of replacing background N2 with CO2, increasing O2 mole fraction and fuel type and rank on a number of qualitative and quantitative parameters such as ignition/combustion mode, ignition temperature, ignition delay time, combustion temperatures, burnout times and envelope flame soot volume fractions. Regarding ignition, in the quiescent gas condition, bituminous and sub-bituminous coal particles experienced homogeneous ignition in both O2/N 2 and O2/CO2 atmospheres, while in the active gas flow condition, heterogeneous ignition was evident in O2/CO 2. Anthracite, semi-anthracite and lignites mostly experienced heterogeneous ignition in either O2/N2 or O2/CO2 atmospheres in both flow conditions. Replacing the N2 by CO 2 slightly increased the ignition temperature (30--40K). Ignition temperatures increased with the enhancement of coal rank in either air or oxy-fuel combustion conditions. However, increasing oxygen mole fraction decreased the ignition temperature for all coals. The ignition delay of coal particles was prolonged in the slow-heating O2/CO2 atmospheres, relative to the faster-heating O2/N2 atmospheres, particularly at high-diluent mole fractions. At higher O2 mole fractions, ignition delays decreased in both environments. Higher rank fuels such as anthracite and semi-anthracite experienced higher ignition delays while lower rank fuels such as lignite and biomasses experienced lower igniton delay times. In combustion, fuel particles were observed to burn in different modes, such as two-mode, or in one-mode combustion, depending on their rank and the furnace conditions. Strong tendencies were observed for all fuels to burn in one-mode when N2 was replaced by CO2, and when O 2 mole fraction increased in both environments. Moreover, increasing the coal rank, from lignite to bituminous, enhanced the tendency of coal particles to exhibit a two-mode combustion behavior. Particle luminosity, fragmentation and deduced temperatures were higher in O2/N2 than in O2/CO2 atmospheres, and corresponding burnout times were shorter, at the same O2 mole fractions. Particle luminosity and temperatures increased with increasing O2 mole fractions in both N2 and in CO2 background gases, and corresponding burnout times decreased with increasing O2 mole fractions. Bituminous coal particles swelled, whereas sub-bituminous coal particles exhibited limited fragmentation prior to and during the early stages of combustion. Lignite coal particles fragmented extensively and burned in one-mode regardless of the O2 mole fraction and the background gas. The timing of fragmentation (prior or after ignition) and the number of fragments depended on the type of the lignite and on the particle shape. Temperatures and burnout times of particles were also affected by the combustion mode. In nearly all bituminous and biomass particles combustion, sooty envelope flames were formed around the particles. Replacement of background N 2 by CO2 gas decreased the average soot volume fraction, fv, whereas increasing O2 from 20% to 30--40% increased the fv and then further increasing O2 to 100% decreased the soot volume fraction drastically. bituminous coal particle flames generated lower soot volume fractions in the range 2x10 -5--9x10-5, depending on O2 mole fraction. Moreover, biomass particle flames were optically thin and of equal-sized at all O2 mole fractions. (Abstract shortened by UMI.).
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USDA-ARS?s Scientific Manuscript database
Genetic improvement of fiber quality is necessary to meet the requirements of processors and users of cotton fiber. To foster genetic improvement of cotton fiber quality, adequate genetic variation for the quantitatively inherited physical properties of cotton is required. Additionally, knowledge of...
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Revised Geochronology and Magnetostratigraphy of Northwest Iceland
NASA Astrophysics Data System (ADS)
Riishuus, M. S.; Duncan, R. A.; Kristjansson, L.
2013-12-01
The lava pile of the NW peninsula of Iceland is largely composed of tholeiites, with less abundant olivine basalts and plagioclase porphyritic basalts, with a modest regional dip toward the southeast. The peninsula attracted the attention of scientists already in the eighteenth century, especially its occurrences of fossiliferous sediment layers of variable volcaniclastic character containing lignite. Fieldwork in a large stratigraphic mapping project was initiated in 1975 (McDougall et al., 1984). This project involved sampling of 1261 lava flows for paleomagnetic studies of ~50 correlated profiles in the western and eastern coastal areas of the peninsula, and K-Ar dating of >70 lava flows in the profiles. On the western side the average rate of buildup of the lava pile was found to be ~1800 m/Myr, corresponding to a mean time interval between successive lava flows of about 5000 yrs, and contrasting with a much lower rate of ~700 m/Myr for the younger eastern sequence. Only a few radiometric ages have been obtained from the Northwest peninsula after 1984 without adding much to the previous knowledge of the buildup of the peninsula. The effort by McDougall et al. (1984) has however been followed by three smaller but sizable projects on the stratigraphy and paleomagnetism of the peninsula. In one of these studies, altogether 307 lavas were sampled in 12 profiles in the tributary fjords south of Ísafjardardjúp. Using paleomagnetic polarities, lava petrography, and the ~12 Ma sediment horizon, a 2.6 km composite section was correlated with a central 2.8 km segment of the 4.1 km thick western section of McDougall et al. (1984). Here we present >50 new Ar-Ar ages on basaltic lava flows from magnetostratigraphic profiles across the peninsula. The results show that the preserved lavas below the oldest sediment horizon were erupted between ~17 and ~16 Ma at a low growth rate for the lava pile of 350m/Myr. The onset of volcanism above the unconformity occurred by 14.5-15.0 Ma - and at a significantly higher growth rate. This suggests that the period of volcanic quiescence, during which the lignite-bearing laterites were deposited, was long-lived (1-1.5 Myr). Our results also reveal significant variations in growth rates SW-NE along strike of the lava pile, presumably reflecting differences in the volcanic productivity along the rift zone, as well as higher resolution of temporal growth rate variations from 17 to 8 Ma (~350 m/Myr @ 17-15 Ma, ~2200m/Myr @ 14.5-13.8 Ma, ~700m/Myr @ 13.8-11.6 Ma, ~1500m/Myr @ 11.6-10.6 Ma, ~800m/Myr @ 10.5-8 Ma) than hitherto thought. At several stratigraphic levels the new absolute ages are significantly older than the recalculated age data from earlier studies. This requires reassessment of the correlation of the observed polarity patterns with the Geomagnetic Polarity Time Scale. McDougall, I., Kristjansson, L. and Saemundsson, K., 1984. Magnetostratigraphy and geochronology of Northwest Iceland. Journal of Geophysical Research 89, 7029-7060.
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Application of remote sensing to state and regional problems
NASA Technical Reports Server (NTRS)
Miller, W. F.; Clark, J. R.; Solomon, J. L.; Duffy, B.; Minchew, K.; Wright, L. H. (Principal Investigator)
1981-01-01
The objectives, accomplishments, and future plans of several LANDSAT applications projects in Mississippi are discussed. The applications include land use planning in Lowandes County, strip mine inventory and reclamation, white tailed deer habitat evaluation, data analysis support systems, discrimination of forest habitats in potential lignite areas, changes in gravel operations, and determination of freshwater wetlands for inventory and monitoring. In addition, a conceptual design for a LANDSAT based information system is discussed.
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The History of the Coal Mining Industry and Mining Accidents in the World and Turkey
Atalay, Figen
2015-01-01
Three per thousand of the world’s coal reserves and 2% of lignite reserves exist in Turkey. Coal mining is the highest ranking industry for accidents and deaths per capita. For this reason, continuous monitoring and more attention should be gıven to the mining industry. In this review, the basic statistical data related to Turkey’s mining and mining disasters are summarized. PMID:29404107
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Benomyl-resistant mutant strain of Trichoderma sp. with increased mycoparasitic activity.
Olejníková, P; Ondrusová, Z; Krystofová, S; Hudecová, D
2010-01-01
Application of UV radiation to the strain Trichoderma sp. T-bt (isolated from lignite) resulted in the T-brm mutant which was resistant to the systemic fungicide benomyl. The tub2 gene sequence in the T-brm mutant differed from the parent as well as the collection strain (replacing tyrosine with histidine in the TUB2 protein). Under in vitro conditions this mutant exhibited a higher mycoparasitic activity toward phytopathogenic fungi.
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Code of Federal Regulations, 2010 CFR
2010-04-01
... domestic iron ore with a retained economic interest. 1.631-3 Section 1.631-3 Internal Revenue INTERNAL...) Sales and Exchanges § 1.631-3 Gain or loss upon the disposal of coal or domestic iron ore with a... disposes of coal (including lignite), or iron ore mined in the United States, held for more than 1 year (6...
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Code of Federal Regulations, 2012 CFR
2012-04-01
... domestic iron ore with a retained economic interest. 1.631-3 Section 1.631-3 Internal Revenue INTERNAL...) Sales and Exchanges § 1.631-3 Gain or loss upon the disposal of coal or domestic iron ore with a... disposes of coal (including lignite), or iron ore mined in the United States, held for more than 1 year (6...
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Code of Federal Regulations, 2011 CFR
2011-04-01
... domestic iron ore with a retained economic interest. 1.631-3 Section 1.631-3 Internal Revenue INTERNAL...) Sales and Exchanges § 1.631-3 Gain or loss upon the disposal of coal or domestic iron ore with a... disposes of coal (including lignite), or iron ore mined in the United States, held for more than 1 year (6...
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Code of Federal Regulations, 2013 CFR
2013-04-01
... domestic iron ore with a retained economic interest. 1.631-3 Section 1.631-3 Internal Revenue INTERNAL...) Sales and Exchanges § 1.631-3 Gain or loss upon the disposal of coal or domestic iron ore with a... disposes of coal (including lignite), or iron ore mined in the United States, held for more than 1 year (6...
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Code of Federal Regulations, 2014 CFR
2014-04-01
... domestic iron ore with a retained economic interest. 1.631-3 Section 1.631-3 Internal Revenue INTERNAL...) Sales and Exchanges § 1.631-3 Gain or loss upon the disposal of coal or domestic iron ore with a... disposes of coal (including lignite), or iron ore mined in the United States, held for more than 1 year (6...
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NASA Astrophysics Data System (ADS)
Ginsburg, Léonard; Durrani, Khadim Hussain; Kassi, Akhtar Mohammad; Welcomme, Jean-Loup
1999-02-01
This paper deals with the discovery and the description of a new Anthracobunidae, Nakusia shahrigensis gen. et sp. nov., from the Ghazij Formation, Early Eocene, of the Kach area, west of Quetta in Pakistan. Discussion and comparison are made with the other anthracobunids, species and genera, the validity of which is discussed. Position of the Anthracobunidae in the Classification is discussed.
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Variation in cooking and eating quality traits in Japanese rice germplasm accessions
Hori, Kiyosumi; Suzuki, Keitaro; Iijima, Ken; Ebana, Kaworu
2016-01-01
The eating quality of cooked rice is important and determines its market price and consumer acceptance. To comprehensively describe the variation of eating quality in 183 rice germplasm accessions, we evaluated 33 eating-quality traits including amylose and protein contents, pasting properties of rice flour, and texture of cooked rice grains. All eating-quality traits varied widely in the germplasm accessions. Principal-components analysis (PCA) revealed that allelic differences in the Wx gene explained the largest proportion of phenotypic variation of the eating-quality traits. In 146 accessions of non-glutinous temperate japonica rice, PCA revealed that protein content and surface texture of the cooked rice grains significantly explained phenotypic variations of the eating-quality traits. An allelic difference based on simple sequence repeats, which was located near a quantitative trait locus (QTL) on the short arm of chromosome 3, was associated with differences in the eating quality of non-glutinous temperate japonica rice. These results suggest that eating quality is controlled by genetic factors, including the Wx gene and the QTL on chromosome 3, in Japanese rice accessions. These genetic factors have been consciously selected for eating quality during rice breeding programs in Japan. PMID:27162502
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Variation in cooking and eating quality traits in Japanese rice germplasm accessions.
Hori, Kiyosumi; Suzuki, Keitaro; Iijima, Ken; Ebana, Kaworu
2016-03-01
The eating quality of cooked rice is important and determines its market price and consumer acceptance. To comprehensively describe the variation of eating quality in 183 rice germplasm accessions, we evaluated 33 eating-quality traits including amylose and protein contents, pasting properties of rice flour, and texture of cooked rice grains. All eating-quality traits varied widely in the germplasm accessions. Principal-components analysis (PCA) revealed that allelic differences in the Wx gene explained the largest proportion of phenotypic variation of the eating-quality traits. In 146 accessions of non-glutinous temperate japonica rice, PCA revealed that protein content and surface texture of the cooked rice grains significantly explained phenotypic variations of the eating-quality traits. An allelic difference based on simple sequence repeats, which was located near a quantitative trait locus (QTL) on the short arm of chromosome 3, was associated with differences in the eating quality of non-glutinous temperate japonica rice. These results suggest that eating quality is controlled by genetic factors, including the Wx gene and the QTL on chromosome 3, in Japanese rice accessions. These genetic factors have been consciously selected for eating quality during rice breeding programs in Japan.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Warwick, P.D.
This collection of papers provides an introduction to the concept of coal systems analysis and contains examples of how coal systems analysis can be used to understand, characterize, and evaluate coal and coal gas resources. Chapter are: Coal systems analysis: A new approach to the understanding of coal formation, coal quality and environmental considerations, and coal as a source rock for hydrocarbons by Peter D. Warwick. Appalachian coal assessment: Defining the coal systems of the Appalachian Basin by Robert C. Milici. Subtle structural influences on coal thickness and distribution: Examples from the Lower Broas-Stockton coal (Middle Pennsylvanian), Eastern Kentucky Coalmore » Field, USA by Stephen F. Greb, Cortland F. Eble, and J.C. Hower. Palynology in coal systems analysis The key to floras, climate, and stratigraphy of coal-forming environments by Douglas J. Nichols. A comparison of late Paleocene and late Eocene lignite depositional systems using palynology, upper Wilcox and upper Jackson Groups, east-central Texas by Jennifer M.K. O'Keefe, Recep H. Sancay, Anne L. Raymond, and Thomas E. Yancey. New insights on the hydrocarbon system of the Fruitland Formation coal beds, northern San Juan Basin, Colorado and New Mexico, USA by W.C. Riese, William L. Pelzmann, and Glen T. Snyder.« less
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Quality of Selected Hungarian Coals
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.
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Flores, Romeo M.; Stricker, Gary D.; Papasin, Ramon F.; Pendon, Ronaldo R.; del Rosario, Rogelio A.; Malapitan, Ruel T.; Pastor, Michael S.; Altomea, Elmer A.; Cuaresma, Federico; Malapitan, Armando S.; Mortos, Benjamin R.; Tilos, Elizabeth N.
2006-01-01
Introduction: The Republic of the Philippines has some 19 coal districts that contain coal deposits ranging from Eocene to Pleistocene in age. These coal districts include: (1) Catanduanes (Eocene); (2) Cebu, Zamboanga Sibuguey, Bukidnon, Maguindanao, Sarangani, and Surigao (Oligocene to Miocene); (3) Batan Island, Masbate, Semirara (including Mindoro), and Quezon-Polilio (lower-upper Miocene); (4) Davao, Negros, and Sorsogon (middle-upper Miocene); (5) Cotabato (lower Miocene-lower Pliocene), Cagayan-Isabella, and Quirino (upper Miocene-Pliocene); (6) Sultan Kudarat (upper Miocene-Pleistocene); and (7) Samar-Leyte (lower Pliocene-Pleistocene). In general, coal rank is directly related to the age of the deposits - for example, the Eocene coal is semi-anthracite and the Pliocene-Pleistocene coal is lignite. Total coal resources in these 19 coal districts, which are compiled by the Geothermal and Coal Resources Development Division (GCRDD) of the Department of Energy of the Philippines, are estimated at a minimum of 2,268.4 million metric tonnes (MMT) (approximately 2.3 billion metric tones). The largest resource (550 MMT) is the subbituminous coal in the Semirara (including Mindoro) coal district, and the smallest (0.7 MMT) is the lignite-subbituminous coal in the Quirino coal district. The combined lignite and subbituminous coal resources, using the classification by GCRDD and including Semirara and Surigao coal districts, are about 1,899.2 MMT, which make up about 84 percent of the total coal resources of the Philippines. The remaining resources are composed of bituminous and semi-anthracite coal. The subbituminous coal of Semirara Island in the Mindoro- Semirara coal district (fig. 2) is known to contain coalbed methane (CBM), with the coal being comparable in gas content and adsorption isotherms to the coal of the Paleocene Fort Union Formation in the Powder River Basin in Wyoming, USA (Flores and others, 2005). As a consequence, the presence of CBM in the Semirara coal led to the present study of determining the adsorption isotherms, or gas (CBM) holding or storage capacity, of coal beds of various ages from selected coal districts in the Philippines. Samples for the study were collected from the Batan Island, Catanduanes, Cagayan-Isabella, Cebu, Negros, Samar, Semirara, Cotabato, Surigao, and Malangas coalfield of the Zamboanga Sibuguey coal districts by five field geology teams from the GCRDD.
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NASA Astrophysics Data System (ADS)
Dimitrakopoulos, D.; Grigorakou, E.; Koumantakis, J.
2003-04-01
Vegoritis Lake, which is located at Vegoritis closed Basin in West Macedonia, Greece, is the biggest lake in Greece. In 1994 the area of the lake was 35 Km2 with maximum depth 42 m at the northwestern part of the lake. It is the final receiving body of the surface runoff of the hydrological basin. Moreover, it is the surficial appearance of an enormous and not well-known karstic aquifer. Being a closed hydrological basin any interference in surface or groundwater conditions in every part of its area affects the level of the lake. The level of the lake in 1900 was 525 masl, in 1942 was 542 masl reaching the higher level of 543 masl in 1956. The increase of the level of the lake was due to the drainage of Ptolemais (Sarigiol) swamp through Soulou drain ditches that transfer the water in the lake. Since then, a continuous drawdown took place with small periods of rising of water level. Today, the level of the lake is declined in a smaller rate having reached the level of 510 masl. Water coming from the lake has been used in the past, and in some cases still does, for agricultural, industrial and domestic use, for hydropower generation and for the cooling system of power plants. Moreover, P.P.C. (Public Power Corporation of Greece) develops an intense activity in the area with the exploitation of the lignite deposits of the basin and power generation in several Power Plants. Few years ago significant quantities from Vegoritis Lake were used for hydro power of Agras Power Plant. With the elaboration of the existent data (water level measurements, recharge, discharge) the connection between the lowering of the surface of the lake and the subtracted quantities through the Arnissa Tunel the first years of its use, is obvious. The last twenty years the condition has change. Outflow through the Arnissa Tunnel for hydropower has stopped. The continued lowering of the level of the lake is caused, mainly, by overexploitation due to the intense increase of the irrigating land. The dewatering of the aquifers for the protection of the lignite mine seems to have an insignificant influence on the aquatic balance, as the water is discharged again into the streams and rivers of the closed basin.
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Co-gasification of solid waste and lignite - a case study for Western Macedonia.
Koukouzas, N; Katsiadakis, A; Karlopoulos, E; Kakaras, E
2008-01-01
Co-gasification of solid waste and coal is a very attractive and efficient way of generating power, but also an alternative way, apart from conventional technologies such as incineration and landfill, of treating waste materials. The technology of co-gasification can result in very clean power plants using a wide range of solid fuels but there are considerable economic and environmental challenges. The aim of this study is to present the available existing co-gasification techniques and projects for coal and solid wastes and to investigate the techno-economic feasibility, concerning the installation and operation of a 30MW(e) co-gasification power plant based on integrated gasification combined cycle (IGCC) technology, using lignite and refuse derived fuel (RDF), in the region of Western Macedonia prefecture (WMP), Greece. The gasification block was based on the British Gas-Lurgi (BGL) gasifier, while the gas clean-up block was based on cold gas purification. The competitive advantages of co-gasification systems can be defined both by the fuel feedstock and production flexibility but also by their environmentally sound operation. It also offers the benefit of commercial application of the process by-products, gasification slag and elemental sulphur. Co-gasification of coal and waste can be performed through parallel or direct gasification. Direct gasification constitutes a viable choice for installations with capacities of more than 350MW(e). Parallel gasification, without extensive treatment of produced gas, is recommended for gasifiers of small to medium size installed in regions where coal-fired power plants operate. The preliminary cost estimation indicated that the establishment of an IGCC RDF/lignite plant in the region of WMP is not profitable, due to high specific capital investment and in spite of the lower fuel supply cost. The technology of co-gasification is not mature enough and therefore high capital requirements are needed in order to set up a direct co-gasification plant. The cost of electricity estimated was not competitive, compared to the prices dominating the Greek electricity market and thus further economic evaluation is required. The project would be acceptable if modular construction of the unit was first adopted near operating power plants, based on parallel co-gasification, and gradually incorporating the remaining process steps (gas purification, power generation) with the aim of eventually establishing a true direct co-gasification plant.
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Riparian plant litter quality increases with latitude.
Boyero, Luz; Graça, Manuel A S; Tonin, Alan M; Pérez, Javier; J Swafford, Andrew; Ferreira, Verónica; Landeira-Dabarca, Andrea; A Alexandrou, Markos; Gessner, Mark O; McKie, Brendan G; Albariño, Ricardo J; Barmuta, Leon A; Callisto, Marcos; Chará, Julián; Chauvet, Eric; Colón-Gaud, Checo; Dudgeon, David; Encalada, Andrea C; Figueroa, Ricardo; Flecker, Alexander S; Fleituch, Tadeusz; Frainer, André; Gonçalves, José F; Helson, Julie E; Iwata, Tomoya; Mathooko, Jude; M'Erimba, Charles; Pringle, Catherine M; Ramírez, Alonso; Swan, Christopher M; Yule, Catherine M; Pearson, Richard G
2017-09-05
Plant litter represents a major basal resource in streams, where its decomposition is partly regulated by litter traits. Litter-trait variation may determine the latitudinal gradient in decomposition in streams, which is mainly microbial in the tropics and detritivore-mediated at high latitudes. However, this hypothesis remains untested, as we lack information on large-scale trait variation for riparian litter. Variation cannot easily be inferred from existing leaf-trait databases, since nutrient resorption can cause traits of litter and green leaves to diverge. Here we present the first global-scale assessment of riparian litter quality by determining latitudinal variation (spanning 107°) in litter traits (nutrient concentrations; physical and chemical defences) of 151 species from 24 regions and their relationships with environmental factors and phylogeny. We hypothesized that litter quality would increase with latitude (despite variation within regions) and traits would be correlated to produce 'syndromes' resulting from phylogeny and environmental variation. We found lower litter quality and higher nitrogen:phosphorus ratios in the tropics. Traits were linked but showed no phylogenetic signal, suggesting that syndromes were environmentally determined. Poorer litter quality and greater phosphorus limitation towards the equator may restrict detritivore-mediated decomposition, contributing to the predominance of microbial decomposers in tropical streams.
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Partington, Andrew; Chew, Derek P; Ben-Tovim, David; Horsfall, Matthew; Hakendorf, Paul; Karnon, Jonathan
2017-03-01
Objective Unwarranted variation in clinical practice is a target for quality improvement in health care, but there is no consensus on how to identify such variation or to assess the potential value of initiatives to improve quality in these areas. This study illustrates the use of a triple test, namely the comparative analysis of processes of care, costs and outcomes, to identify and assess the burden of unwarranted variation in clinical practice. Methods Routinely collected hospital and mortality data were linked for patients presenting with symptoms suggestive of acute coronary syndromes at the emergency departments of four public hospitals in South Australia. Multiple regression models analysed variation in re-admissions and mortality at 30 days and 12 months, patient costs and multiple process indicators. Results After casemix adjustment, an outlier hospital with statistically significantly poorer outcomes and higher costs was identified. Key process indicators included admission patterns, use of invasive diagnostic procedures and length of stay. Performance varied according to patients' presenting characteristics and time of presentation. Conclusions The joint analysis of processes, outcomes and costs as alternative measures of performance inform the importance of reducing variation in clinical practice, as well as identifying specific targets for quality improvement along clinical pathways. Such analyses could be undertaken across a wide range of clinical areas to inform the potential value and prioritisation of quality improvement initiatives. What is known about the topic? Variation in clinical practice is a long-standing issue that has been analysed from many different perspectives. It is neither possible nor desirable to address all forms of variation in clinical practice: the focus should be on identifying important unwarranted variation to inform actions to reduce variation and improve quality. What does this paper add? This paper proposes the comparative analysis of processes of care, costs and outcomes for patients with similar diagnoses presenting at alternative hospitals, using linked, routinely collected data. This triple test of performance indicators extracts maximum value from routine data to identify priority areas for quality improvement to reduce important and unwarranted variations in clinical practice. What are the implications for practitioners? The proposed analyses need to be applied to other clinical areas to demonstrate the general application of the methods. The outputs can then be validated through the application of quality improvement initiatives in clinical areas with identified important and unwarranted variation. Validated frameworks for the comparative analysis of clinical practice provide an efficient approach to valuing and prioritising actions to improve health service quality.
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Huang, Jinliang; Huang, Yaling; Zhang, Zhenyu
2014-01-01
Surface water samples of baseflow were collected from 20 headwater sub-watersheds which were classified into three types of watersheds (natural, urban and agricultural) in the flood, dry and transition seasons during three consecutive years (2010–2012) within a coastal watershed of Southeast China. Integrating spatial statistics with multivariate statistical techniques, river water quality variations and their interactions with natural and anthropogenic controls were examined to identify the causal factors and underlying mechanisms governing spatiotemporal patterns of water quality. Anthropogenic input related to industrial effluents and domestic wastewater, agricultural activities associated with the precipitation-induced surface runoff, and natural weathering process were identified as the potential important factors to drive the seasonal variations in stream water quality for the transition, flood and dry seasons, respectively. All water quality indicators except SRP had the highest mean concentrations in the dry and transition seasons. Anthropogenic activities and watershed characteristics led to the spatial variations in stream water quality in three types of watersheds. Concentrations of NH4 +-N, SRP, K+, CODMn, and Cl− were generally highest in urban watersheds. NO3 –N Concentration was generally highest in agricultural watersheds. Mg2+ concentration in natural watersheds was significantly higher than that in agricultural watersheds. Spatial autocorrelations analysis showed similar levels of water pollution between the neighboring sub-watersheds exhibited in the dry and transition seasons while non-point source pollution contributed to the significant variations in water quality between neighboring sub-watersheds. Spatial regression analysis showed anthropogenic controls played critical roles in variations of water quality in the JRW. Management implications were further discussed for water resource management. This research demonstrates that the coupled effects of natural and anthropogenic controls involved in watershed processes, contribute to the seasonal and spatial variation of headwater stream water quality in a coastal watershed with high spatial variability and intensive anthropogenic activities. PMID:24618771
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Water based drilling mud additive
DOE Office of Scientific and Technical Information (OSTI.GOV)
McCrary, J.L.
1983-12-13
A water based fluid additive useful in drilling mud used during drilling of an oil or gas well is disclosed, produced by reacting water at temperatures between 210/sup 0/-280/sup 0/ F. with a mixture comprising in percent by weight: gilsonite 25-30%, tannin 7-15%, lignite 25-35%, sulfonating compound 15-25%, water soluble base compound 5-15%, methylene-yielding compound 1-5%, and then removing substantially all of the remaining water to produce a dried product.
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Simulation of one-dimensional heat transfer system based on the blended coal combustion
NASA Astrophysics Data System (ADS)
Jin, Y. G.; Li, W. B.; Cheng, Z. S.; Cheng, J. W.; liu, Y.
2017-12-01
In this paper, the supercritical boiler thermodynamic calculation model is studied. Three types of heat exchangers are proposed, namely furnace (total radiation type), semi-radiation and convection, and discussed. Two cases were simulated - mixing of two bituminous coals and mixing of a bituminous coal and lignite- order to analyze the performance on the flue gas side. The study shows that the influence of flue air leakage and gas distribution coefficient on the system.
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1989-06-01
FLUE GAS DESULFURIZATION EVALUATION A-1/A-2 3-1. 3 BOILER STACK EMISSION CONTROL WITH...Appendices A - BACT Flue Gas Desulfurization Evaluation B - BACT Off- Gas Refrigeration Evaluation v LIST OF FIGURES Figure Page 1. Material Balance for...2. Desulfurize the flue gases from the Riley boilers when firing with high sulfur oils or lignite. Options in this category include commercial wet
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Characterization of airborne particles at a high-btu coal-gasification pilot plant.
Davidson, C I; Santhanam, S; Stetter, J R; Flotard, R D; Gebert, E
1982-12-01
Airborne particles in fugitive emissions have been measured at a slagging fixed-bed coal-gasification pilot plant using lignite. Sampling was conducted during shutdown operations and opening of the gasifier following an aborted startup. Aerosol collected with a Sierra high-volume impactor was subjected to analysis by gas chromatography, mass spectrometry, and scanning electron microscopy; aerosol collected with an Andersen low-volume impactor was subjected to flameless atomic absorption analysis. The data show that the bulk of the trace organic material is associated with small particles: these data are similar to data on ambient air reported in the literature. Particle morphologies resemble those of fly ash from coal combustion, including smooth spheres, vesicular spheres, and crystalline material. Trace element size distributions are bimodal and resemble data for ambient air. Pb-containing particles are generally submicron, while particles containing Al, Fe, and other crustal species are mostly of supermicron size. Aluminum-based aerosol enrichment factors calculated from the lignite composition show that the composition of the aerosol resembles that of the coal, with the exception of modest enrichments of Mg, Na, As, and Pb in the submicron size range. Aerosol enrichment factors based on the earth's crustal composition are somewhat greater than those based on coal composition for several elements, suggesting potential errors in using crustal enrichment data to investigate chemical fractionation during aerosol formation.
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Appalachian coal assessment: Defining the coal systems of the Appalachian basin
Milici, R.C.
2005-01-01
The coal systems concept may be used to organize the geologic data for a relatively large, complex area, such as the Appalachian basin, in order to facilitate coal assessments in the area. The concept is especially valuable in subjective assessments of future coal production, which would require a detailed understanding of the coal geology and coal chemistry of the region. In addition, subjective assessments of future coal production would be enhanced by a geographical information system that contains the geologic and geochemical data commonly prepared for conventional coal assessments. Coal systems are generally defined as one or more coal beds or groups of coal beds that have had the same or similar genetic history from their inception as peat deposits, through their burial, diagenesis, and epigenesis to their ultimate preservation as lignite, bituminous coal, or anthracite. The central and northern parts of the Appalachian basin contain seven coal systems (Coal Systems A-G). These systems may be defined generally on the following criteria: (1) on the primary characteristics of their paleopeat deposits, (2) on the stratigraphic framework of the Paleozoic coal measures, (3) on the relative abundance of coal beds within the major stratigraphic groupings, (4) on the amount of sulfur related to the geologic and climatic conditions under which paleopeat deposits accumulated, and (5) on the rank of the coal (lignite to anthracite). ??2005 Geological Society of America.
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Tong, Kun; Lin, Aiguo; Ji, Guodong; Wang, Dong; Wang, Xinghui
2016-05-05
The adsorption of organic pollutants from super heavy oil wastewater (SHOW) by lignite activated coke (LAC) was investigated. Specifically, the effects of LAC adsorption on pH, BOD5/COD(Cr)(B/C), and the main pollutants before and after adsorption were examined. The removed organic pollutants were characterized by Fourier transform infrared spectroscopy (FTIR), Boehm titrations, gas chromatography-mass spectrometry (GC-MS), and liquid chromatography with organic carbon detection (LC-OCD). FTIR spectra indicated that organic pollutants containing -COOH and -NH2 functional groups were adsorbed from the SHOW. Boehm titrations further demonstrated that carboxyl, phenolic hydroxyl, and lactonic groups on the surface of the LAC increased. GC-MS showed that the removed main organic compounds are difficult to be degraded or extremely toxics to aquatic organisms. According to the results of LC-OCD, 30.37 mg/L of dissolved organic carbons were removed by LAC adsorption. Among these, hydrophobic organic contaminants accounted for 25.03 mg/L. Furthermore, LAC adsorption was found to increase pH and B/C ratio of the SHOW. The mechanisms of adsorption were found to involve between the hydrogen bonding and the functional groups of carboxylic, phenolic, and lactonic on the LAC surface. In summary, all these results demonstrated that LAC adsorption can remove bio-refractory DOCs, which is beneficial for biodegradation. Copyright © 2016. Published by Elsevier B.V.
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Bacteria in deep coastal plain sediments of Maryland: A possible source of CO2 to groundwater
NASA Astrophysics Data System (ADS)
Chapelle, Francis H.; Zelibor, Joseph L., Jr.; Grimes, D. Jay; Knobel, Leroy L.
1987-08-01
Nineteen cores of unconsolidated Coastal Plain sediments obtained from depths of 14 to 182 m below land surface near Waldorf, Maryland, were collected and examined for metabolically active bacteria. The age of the sediments cored range from Miocene to Early Cretaceous. Acridine orange direct counts of total (viable and nonviable) bacteria in core subsamples ranged from 108 to 104 bacteria/g of dry sediment. Direct counts of viable bacteria ranged from 106 to 103 bacteria/g of dry sediment. Three cores contained viable methanogenic bacteria, and seven cores contained viable sulfate-reducing bacteria. The observed presence of bacteria in these sediments suggest that heterotrophic bacterial metabolism, with lignitic organic material as the primary substrate, is a plausible source of CO2 to groundwater. However, the possibility that abiotic processes also produce CO2 cannot be ruled out. Estimated rates of CO2 production in the noncalcareous Magothy/Upper Patapsco and Lower Patapsco aquifers based on mass balance of dissolved inorganic carbon, groundwater flow rates, and flow path segment lengths are in the range 10-3 to 10-5 mmol L-1 yr-1. Isotope balance calculations suggest that aquifer-generated CO2 is much heavier isotopically (˜—10 to + 5 per mil) than lignite (˜-24 per mil) present in these sediments. This may reflect isotopic fractionation during methanogenesis and possibly other bacterially mediated processes.
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Bourliva, Anna; Papadopoulou, Lambrini; Aidona, Elina; Simeonidis, Konstantinos; Vourlias, George; Devlin, Eamonn; Sanakis, Yiannis
2017-01-01
The mineralogy, morphology, and chemical composition of magnetic fractions separated from fly ashes (FAs) originating from Greek lignite-burning power plants was investigated. The oral bioaccessibility of potentially harmful elements (PHEs) from the fly ash magnetic fractions (FAMFs) was also assessed using in vitro gastrointestinal extraction (BARGE Unified Bioaccessibility Method, UBM). The FAMFs isolated were in the range 4.6-18.4%, and their mass specific magnetic susceptibility ranged from 1138 × 10 -8 to 1682 × 10 -8 m 3 /kg. XRD analysis and Mossbauer spectroscopy indicated that the dominant iron species were Fe-rich aluminosilicate glass along with magnetite, hematite, and maghemite (in decreasing order). The raw FAs exhibited differences in their chemical composition, indicating the particularity of every lignite basin. The elemental contents of FAMFs presented trends with fly ash type; thus, the FAMFs of high-Ca FAs were enriched in siderophile (Cr, Co, Ni) and lithophile (Cs, Li, Rb) elements and those separated from low-Ca FAs were presented depleted in chalcophile elements. Based on UBM extraction tests, the PHEs were more bioaccessible from the non-magnetic components of the FAs compared to the magnetic ones; however, the bioaccessible fractions estimated for the FAMFs were exceeding 40 % in many cases. Arsenic was found to be significantly bioaccessible (median ~ 80 %) from FAMFs despite the lower As contents in the magnetic fraction.
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Ash from thermal power plants as secondary raw material.
Cudić, Vladica; Kisić, Dragica; Stojiljković, Dragoslava; Jovović, Aleksandar
2007-06-01
The basic characteristic of thermal power plants in the Republic of Serbia is that they use low-grade brown coal (lignite) as a fuel. Depending on the location of coal mines, lignite may have different properties such as heating value, moisture, and mineral content, resulting in different residue upon combustion. Because of several million tonnes of ash and slag generated every year, their granularmetric particle size distribution, and transport and disposal methods, these plants have a negative impact on the environment. According to the waste classification system in the Republic of Serbia, ash and slag from thermal power plants are classified as hazardous waste, but with an option of usability. The proposed revision of waste legislation in Serbia brings a number of simple and modern solutions. A procedure is introduced which allows for end-of-waste criteria to be set, clarifying the point where waste ceases to be waste, and thereby introducing regulatory relief for recycled products or materials that represent low risk for the environment. The new proposal refocuses waste legislation on the environmental impacts of the generation and management of waste, taking into account the life cycle of resources, and develops new waste prevention programmes. Stakeholders, as well as the general public, should have the opportunity to participate in the drawing up of the programmes, and should have access to them.
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Thermo-optical properties of residential coals and combustion aerosols
NASA Astrophysics Data System (ADS)
Pintér, Máté; Ajtai, Tibor; Kiss-Albert, Gergely; Kiss, Diána; Utry, Noémi; Janovszky, Patrik; Palásti, Dávid; Smausz, Tomi; Kohut, Attila; Hopp, Béla; Galbács, Gábor; Kukovecz, Ákos; Kónya, Zoltán; Szabó, Gábor; Bozóki, Zoltán
2018-04-01
In this study, we present the inherent optical properties of carbonaceous aerosols generated from various coals (hard through bituminous to lignite) and their correlation with the thermochemical and energetic properties of the bulk coal samples. The nanoablation method provided a unique opportunity for the comprehensive investigation of the generated particles under well controlled laboratory circumstances. First, the wavelength dependent radiative features (optical absorption and scattering) and the size distribution (SD) of the generated particulate matter were measured in-situ in aerosol phase using in-house developed and customised state-of-the-art instrumentation. We also investigated the morphology and microstructure of the generated particles using Transmission Electron Microscopy (TEM) and Electron Diffraction (ED). The absorption spectra of the measured samples (quantified by Absorption Angström Exponent (AAE)) were observed to be distinctive. The correlation between the thermochemical features of bulk coal samples (fixed carbon (FC) to volatile matter (VM) ratio and calorific value (CV)) and the AAE of aerosol assembly were found to be (r2 = 0.97 and r2 = 0.97) respectively. Lignite was off the fitted curves in both cases most probably due to its high optically inactive volatile material content. Although more samples are necessary to be investigated to draw statistically relevant conclusion, the revealed correlation between CV and Single Scattering Albedo (SSA) implies that climatic impact of coal combusted aerosol could depend on the thermal and energetic properties of the bulk material.
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Co-Liquefaction of Elbistan Lignite with Manure Biomass; Part 1. Effect of Catalyst Concentration
NASA Astrophysics Data System (ADS)
Koyunoglu, Cemil; Karaca, Hüseyin
2017-12-01
The hydrogenation of coal by molecular hydrogen has not been appreciable unless a catalyst has been used, especially at temperatures below 500 °C. Conversion under these conditions is essentially the result of the pyrolysis of coal, although hydrogen increases the yield of conversion due to the stabilization of radicals and other reactive species. Curtis and his co-workers has shown that highly effective and accessible catalyst are required to achieve high levels of oil production from the coprocessing of coal and heavy residua. In their work, powdered hydrotreating catalyst at high loadings an oil-soluble metal salts of organic acids as catalyst precursors achieved the highest levels of activity for coal conversion and oil production. Red mud which is iron-based catalysed has been used in several co-processing studies. It was used as an inexpensive sulphur sink for the H2S evolved to convert Fe into pyrrohotite during coal liquefaction. In this study, Elbistan Lignite (EL) processed with manure using red mud as a catalyst with the range of concentration from 3% to 12%. The main point of using red mud catalyst is to enhance oil products yield of coal liquefaction, which deals with its catalytic activity. On the other hand, red mud acts on EL liquefaction with manure as a catalyst and represents an environmental option to produce lower sulphur content oil products as well.
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Coal-bed methane potential in Montana
DOE Office of Scientific and Technical Information (OSTI.GOV)
Campen, E.
1991-06-01
Montana's coal resources are the second largest of the US, with coal underlying approximately 35% of the state. These resources are estimated at 478 billion tons. Associated coal-bed methane resources are estimated to be 14 tcf. The coals of Montana range from Jurassic to early Tertiary in age and from lignite to low-volatile bituminous in rank. Thickness, rank, maceral composition, and proximate and ultimate analyses all vary vertically and laterally. The state contains eight major coal resource areas. A large percentage of Montana's coal consists of the Paleocene Fort Union lignites of eastern Montana, generally considered of too low amore » rank to contain significant methane resources. Most of the state's other coal deposits are higher in rank and contain many recorded methane shows. During Cretaceous and Tertiary times, regressive-transgressive cycles resulted in numerous coal-bearing sequences. Major marine regressions allowed the formation of large peat swamps followed by transgressions which covered the swamps with impervious marine shales, preventing the already forming methane from escaping. About 75% of Montana's coal is less than 1,000 ft below the ground's surface, making it ideal for methane production. Associated water appears to be fresh, eliminating environmental problems. Pipelines are near to most of the major coal deposits. Exploration for coal-bed methane in Montana is still in its infancy but at this time shows commercial promise.« less
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Overcoming Murphy`s Law to gain ERP - a case study at Gibbons Creek Lignite Mine, Texas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lancaster, E.M.; Horbaczewski, J.K.
1997-12-31
As of January 1997, there are 2,586 acres of reclaimed land in the Extended Responsibility Period (ERP) at Gibbons Creek Lignite Mine, Texas. This achievement has taken approximately five years to accomplish - from 1991 to 1996. During this period, there were a number of issues, some of which appeared to follow Murphy`s Law (whatever can go wrong, will go wrong!). For example, the ERP candidate areas were split among three permit areas, which first had to be consolidated to facilitate the ERP process. Minesoil issues, identified as ERP prerequisites, became entangled in an overall renewal/revision of the newly-consolidated Permitmore » 26B. Special-purpose vegetation studies were performed to investigate the effects of different minesoil textures. In the meantime, small depressional areas, wetland/wildlife enhancement areas, reclamation ponds and restored drainages became the subjects of attention from landowners and regulatory agencies. Some of these structures and features were subsequently reclaimed; others were approved via the permitting process. In some cases, the only way out of the impasse was through land acquisition. Finally, after all these issues had been resolved, an unforeseen oil-well drilling program crisscrossed the proposed ERP areas with a network of oil well pads and service roads, requiring a post-mining land use change. Eventually, whatever could go wrong, went right, and entry of lands into ERP was accomplished.« less
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NASA Technical Reports Server (NTRS)
Rhoades, Dawna L.; Waguespack, Blaise, Jr.
2000-01-01
This study examined the service quality of 25 U.S. airlines (1987-1996) using data from the Department of Transportation's Air Travel Consumer Report. After a total quality and total complaint rate was calculated for these airlines, a 95 percent confidence interval was placed around the yearly and company means calculated to examine those cases that were significantly different from the mean. Results indicate that while the major carriers are converging toward a higher level of quality, there continues to be significant yearly variation. The service quality of regional carriers was much lower than major carriers and showed much greater variation.
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Characterization of variability in pork carcass composition and primal quality
USDA-ARS?s Scientific Manuscript database
The objective was to characterize the factors and production practices that contribute to variation in pork composition and quality. It is possible the variation in pork quality traits, such as color, marbling, and tenderness, contributes to reduced customer confidence in the predictability of finis...
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Time-dependent phosphate dynamics in reclaimed lignite-mine soils under Robinia pseudoacacia L.
NASA Astrophysics Data System (ADS)
Freese, Dirk; Slazak, Anna
2017-04-01
As a consequence of the opencast lignite mining activities in Lusatia/Germany, the cultivation of Short Rotation Coppice plantations (SRC) has been considered as a viable option for reclamation purposes. In this region an area of about 1000 km2 has been degraded. Owing to the unfavourable biotic and abiotic properties of the overburden mining substrate, the biogeochemical processes associated with the soil ecosystem development are in the initial phase. The substrate contains very low amount of nutrients, mainly very low total Phosphate (P) content nearly equal to zero. The lack of P is one of the main issues in reclamation of this marginal site. Therefore, the cultivation of perennial SRC with Robinia pseudoacacia L. is considered as a supporting measurement for effective soil reclamation. In this context, it is important to understand the dynamics of P in this "initial substrate" to describe the P availability and P sorption/desorption.. Iron/aluminium oxides and organic matter are the soil constituents most strongly affecting the reactions and rate of P sorption and desorption, also in post-mining soils. Therefore the interaction of these oxides and organic matter with P is essential with regard to developing effective nutrient management strategies for marginal sites. The study focused on P sorption and desorption with regard to different development stages of R. pseudoacacia L. established in a short rotation coppices on the post mining soils. to describe the P availability (Pav) in relation to total P mobility. The hypothesis is that SRC would cause significant changes in soil P dynamics over time in post lignite mining soils. The trees has been planted in between 1995 and 2007, which means that R. pseudoacacia L. was in a range of 2 to 20 years old at different sampling times. Soil was sampled in 2008 and 2015 at three depths of: 0-3cm, 3-10 cm and 10-30 cm. To characterize the P dynamics different P forms and P sorption/desorption kinetics were analysed. With increasing age of trees the ratio of available P to total P decreased in tendency for all soil layers. The total P content increased slightly over time in all soil layers. But the amount of Fe and Al oxides increased also over time and therefore the overall P sorption capacity increased, too. Hence, the ratio between available P and total P shifted more to the less available forms of P in soil. Within a period of 20 years, R. pseudoacacia L. cultivation on post mining sites increased the contents of available P and total P, repectively. The P sorption increased with time of soil development showing the maximum at the oldest site. Nevertheless, P sorption of these initial post mining soils is still rather low. The results suggest, that the SRC of R. pseudoacacia L. on post mining sites have a positive influence on the P dynamics. References Freese, D., Van Riemsdijk, W.H., Van Der Zee, S.E.A.T.M., 1995. Modelling phosphate-sorption kinetics in acid soils. European Journal of Soil Science 46(2), 239-245. Matos, E.S., Freese, D., Böhm, C., Quinkenstein, A., Hüttl, R.F., 2012. Organic Matter Dynamics in Reclaimed Lignite Mine Soils under Robinia pseudoacacia L. Plantations of Different Ages in Germany. Communications in Soil Science and Plant Analysis 43(5), 745-755.
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Ali, Arshad; Mattsson, Eskil
2017-01-01
Individual tree size variation, which is generally quantified by variances in tree diameter at breast height (DBH) and height in isolation or conjunction, plays a central role in ecosystem functioning in both controlled and natural environments, including forests. However, none of the studies have been conducted in homegarden agroforestry systems. In this study, aboveground biomass, stand quality, cation exchange capacity (CEC), DBH variation, and species diversity were determined across 45 homegardens in the dry zone of Sri Lanka. We employed structural equation modeling (SEM) to test for the direct and indirect effects of stand quality and CEC, via tree size inequality and species diversity, on aboveground biomass. The SEM accounted for 26, 8, and 1% of the variation in aboveground biomass, species diversity and DBH variation, respectively. DBH variation had the strongest positive direct effect on aboveground biomass (β=0.49), followed by the non-significant direct effect of species diversity (β=0.17), stand quality (β=0.17) and CEC (β=-0.05). There were non-significant direct effects of CEC and stand quality on DBH variation and species diversity. Stand quality and CEC had also non-significant indirect effects, via DBH variation and species diversity, on aboveground biomass. Our study revealed that aboveground biomass substantially increased with individual tree size variation only, which supports the niche complementarity mechanism. However, aboveground biomass was not considerably increased with species diversity, stand quality and soil fertility, which might be attributable to the adaptation of certain productive species to the local site conditions. Stand structure shaped by few productive species or independent of species diversity is a main determinant for the variation in aboveground biomass in the studied homegardens. Maintaining stand structure through management practices could be an effective approach for enhancing aboveground biomass in these dry zone homegarden agroforestry systems. Copyright © 2016 Elsevier B.V. All rights reserved.
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Binny, Diana; Mezzenga, Emilio; Lancaster, Craig M; Trapp, Jamie V; Kairn, Tanya; Crowe, Scott B
2017-06-01
The aims of this study were to investigate machine beam parameters using the TomoTherapy quality assurance (TQA) tool, establish a correlation to patient delivery quality assurance results and to evaluate the relationship between energy variations detected using different TQA modules. TQA daily measurement results from two treatment machines for periods of up to 4years were acquired. Analyses of beam quality, helical and static output variations were made. Variations from planned dose were also analysed using Statistical Process Control (SPC) technique and their relationship to output trends were studied. Energy variations appeared to be one of the contributing factors to delivery output dose seen in the analysis. Ion chamber measurements were reliable indicators of energy and output variations and were linear with patient dose verifications. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.
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Regional differences in prescribing quality among elder veterans and the impact of rural residence
Lund, BC; Charlton, ME; Steinman, MA; Kaboli, PJ
2014-01-01
Purpose Medication safety is a critical concern for older adults. Regional variation in potentially inappropriate prescribing practices may reflect important differences in health care quality. Therefore, the objectives of this study were to characterize prescribing quality variation among older adults across geographic region, and to compare prescribing quality across rural versus urban residence. Methods Cross-sectional study of 1,549,824 older adult veterans with regular Veterans Affairs (VA) primary care and medication use during fiscal year 2007. Prescribing quality was measured by 4 indicators of potentially inappropriate prescribing: Zhan criteria drugs to avoid, Fick criteria drugs to avoid, therapeutic duplication, and drug-drug interactions. Frequency differences across region and rural-urban residence were compared using adjusted odds-ratios. Findings Significant regional variation was observed for all indicators. Zhan criteria frequencies ranged from 13.2% in the Northeast to 21.2% in the South. Nationally, rural veterans had a significantly increased risk for inappropriate prescribing according to all quality indicators. However, regional analyses revealed this effect was limited to the South and Northeast, whereas rural residence was neutral in the Midwest and protective in the West. Conclusions Significant regional variation in prescribing quality was observed among older adult veterans, mirroring recent findings among Medicare beneficiaries. The association between rurality and prescribing quality is heterogeneous, and relying solely on national estimates may yield misleading conclusions. While we documented important variations in prescribing quality, the underlying factors driving these trends remain unknown, and they are a vital area for future research affecting older adults in both VA and non-VA health systems. PMID:23551647
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Advancing the Big Five of user-oriented care and accounting for its variations.
Kajonius, Petri; Kazemi, Ali
2016-01-01
Care process quality (i.e. how care is enacted by a care worker toward a client at the interpersonal level) is a strong predictor of satisfaction in a wide range of health care services. The purpose of this paper is to describe the basic elements of care process quality as user-oriented care. Specifically, the questions of how and why quality in user-oriented care varies were investigated in the context of elderly care. Two municipalities were selected for in-depth field studies. First, in each municipality, the authors interviewed and observed care workers' interactions with the older persons in both home care and nursing homes during two weeks (Study 1). Second, in an attempt to gain a deeper understanding of why process quality in terms of user-oriented care varies, the authors conducted interviews with care workers and care unit managers (Study 2). A new taxonomy for categorizing process quality variation, the Big Five of user-oriented care (task-focus, person-focus, affect, cooperation, and time-use), is proposed. In addition, the perceived reasons for process quality variation are reported in our own developed Quality Agents Model, suggesting that variations in care process evaluations may be explained from different perspectives at multiple levels (i.e., older person, care worker-, unit-, department-, and municipality level). The proposed taxonomy and model are useful for describing user-oriented care quality and the reasons for its variations. These findings are of relevance for future quality developments of elderly care services, but also may be adapted to applications in any other enterprise employing a user-oriented approach.
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Lee, Sang Myeon; Park, Kwang Hyun; Jung, Seungon; Park, Hyesung; Yang, Changduk
2018-05-14
For a given π-conjugated polymer, the batch-to-batch variations in molecular weight (M w ) and polydispersity index (Ð) can lead to inconsistent process-dependent material properties and consequent performance variations in the device application. Using a stepwise-heating protocol in the Stille polycondensation in conjunction with optimized processing, we obtained an ultrahigh-quality PTB7 polymer having high M w and very narrow Ð. The resulting ultrahigh-quality polymer-based solar cells demonstrate up to 9.97% power conversion efficiencies (PCEs), which is over 24% enhancement from the control devices fabricated with commercially available PTB7. Moreover, we observe almost negligible batch-to-batch variations in the overall PCE values from ultrahigh-quality polymer-based devices. The proposed stepwise polymerization demonstrates a facile and effective strategy for synthesizing high-quality semiconducting polymers that can significantly improve device yield in polymer-based solar cells, an important factor for the commercialization of organic solar cells, by mitigating device-to-device variations.
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1981-07-01
266 The Blast-Noise Environment of Recoilless Rifles. AD-POOO 267 Shock-Excited hission Spectrum of Tungsten Oxide . AD-POO0 268 Rotational...Absorption Measurements of Atom Concentrations in Reacting Gas Mixtures. 9. Measurements of 0 Atoms in Oxidation of H2 and D2. AD-POOO 283 Direct Measurements...PuIverized Lignite in a Single-Pulse Shock-Tube. AD-POOO 306 Short Residence-Time Pyrolysis and Oxidative Pyrolysis of Bituminous Coals. AD-POOO 307 Shock
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Application of remote sensing to state and regional problems. [Mississippi
NASA Technical Reports Server (NTRS)
Miller, W. F.; Carter, B. D.; Solomon, J. L.; Williams, S. G.; Powers, J. S.; Clark, J. R. (Principal Investigator)
1980-01-01
Progress is reported in the following areas: remote sensing applications to land use planning Lowndes County, applications of LANDSAT data to strip mine inventory and reclamation, white tailed deer habitat evaluation using LANDSAT data, remote sensing data analysis support system, and discrimination of unique forest habitats in potential lignite areas of Mississippi. Other projects discussed include LANDSAT change discrimination in gravel operations, environmental impact modeling for highway corridors, and discrimination of fresh water wetlands for inventory and monitoring.
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NASA Astrophysics Data System (ADS)
Zagibalov, A. V.; Okhotin, A. L.; Volokhov, A. V.
2017-10-01
The paper deals with the problems of initiation and consequences of landslide processes registered in the internal dumps at Mugunsky lignite opencast mine. Water cutting at the internal dump base, availability of clay rocks in the dump bottom, and the bottom incline towards the working face are revealed to be the sources of the landslide process. Some measures are recommended to prevent deformation processes that are possible to take place in the run of mine development.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Spackman, W.; Davis, A.; Walker, P. L.
1979-05-01
Certain important aspects of the chemical and physical composition of American lignite coals are being characterized. Differential scanning calorimetry and thermogravimetric analysis were used to study the interaction between oxygen and seventeen coal chars (40 x 100 mesh) at 100/sup 0/C. The same techniques were used to investigate briefly the interaction between air and a highly caking coal at selected isothermal temperatures in the range 100 to 275/sup 0/C.
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NASA Astrophysics Data System (ADS)
Girolamo, Paolo Di; Scoccione, Andrea; Cacciani, Marco; Summa, Donato; Schween, Jan H.
2018-04-01
This paper illustrates measurements carried out by the Raman lidar BASIL in the frame of HOPE, revealing the presence of a clear-air dark band phenomenon (i.e. the appearance of a minimum in lidar backscatter echoes) in the upper portion of the convective boundary layer. The phenomenon is clearly distinguishable in the lidar backscatter echoes at 1064 nm. This phenomenon is attributed to the presence of lignite aerosol particles advected from the surrounding open pit mines in the vicinity of the measuring site.
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NASA Astrophysics Data System (ADS)
Manocha, S.; Manocha, L. M.; Joshi, Parth; Patel, Bhavesh; Dangi, Gaurav; Verma, Narendra
2013-06-01
Activated carbon are unique and versatile adsorbents having extended surface area, micro porous structure, universal adsorption effect, high adsorption capacity and high degree of surface reactivity. Activated carbons are synthesized from variety of materials. Most commonly used on a commercial scale are cellulosic based precursors such as peat, coal, lignite wood and coconut shell. Variation occurs in precursors in terms of structure and carbon content. Coir having very low bulk density and porous structure is found to be one of the valuable raw materials for the production of highly porous activated carbon and other important factor is its high carbon content. Exploration of good low cost and non conventional adsorbent may contribute to the sustainability of the environment and offer promising benefits for the commercial purpose in future. Carbonization of biomass was carried out in a horizontal muffle furnace. Both carbonization and activation were performed in inert nitrogen atmosphere in one step to enhance the surface area and to develop interconnecting porosity. The types of biomass as well as the activation conditions determine the properties and the yield of activated carbon. Activated carbon produced from biomass is cost effective as it is easily available as a waste biomass. Activated carbon produced by combination of chemical and physical activation has higher surface area of 2442 m2/gm compared to that produced by physical activation (1365 m2/gm).
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Gonzalez, X.I.; Aboal, J.R.; Fernandez, J.A.
2008-11-15
In the present study, we determined the concentrations of Cu, Fe, Mn, and Zn in soil and several trophic compartments at a total of 16 sampling stations. The trophic compartments studied were primary producers, represented by two species of terrestrial mosses (Pseudoescleropodium purum and Hypnum cupressiforme) and oak trees (Quercus robur or Q. pyrenaica); primary consumers, represented by the wood mouse (Apodemus sylvaticus) and the yellow necked mouse (A. flavicollis); secondary consumers, represented by the shrew (Sorex granarius); and finally, detritivores, represented by slugs (Arion ater). Thirteen of the sampling stations were located in mature oak woodlands (Quercus sp.); twomore » of the sampling stations were located in the area surrounding a restored lignite mine dump, and the other in an ultrabasic area. The analytical determinations revealed a lack of significant correlations among trophic compartments, possibly caused by effective regulation of metals by organisms and/or spatial variation in availability of metals from soil or food. Furthermore, the only element that showed a clear pattern of biomagnification was Cu; as for the other elements, there was always some divergence from such a pattern. Finally, the patterns of bioaccumulation in contaminated and woodland sampling stations were very similar, although there was enrichment of the concentrations of Cu, Mn, and Zn in the mice viscera, which, except for Mn, were related to higher edaphic concentrations.« less
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Jassam, Nuthar; Yundt-Pacheco, John; Jansen, Rob; Thomas, Annette; Barth, Julian H
2013-08-01
The implementation of national and international guidelines is beginning to standardise clinical practice. However, since many guidelines have decision limits based on laboratory tests, there is an urgent need to ensure that different laboratories obtain the same analytical result on any sample. A scientifically-based quality control process will be a pre-requisite to provide this level of analytical performance which will support evidence-based guidelines and movement of patients across boundaries while maintaining standardised outcomes. We discuss the finding of a pilot study performed to assess UK clinical laboratories readiness to work to a higher grade quality specifications such as biological variation-based quality specifications. Internal quality control (IQC) data for HbA1c, glucose, creatinine, cholesterol and high density lipoprotein (HDL)-cholesterol were collected from UK laboratories participating in the Bio-Rad Unity QC programme. The median of the coefficient of variation (CV%) of the participating laboratories was evaluated against the CV% based on biological variation. Except creatinine, the other four analytes had a variable degree of compliance with the biological variation-based quality specifications. More than 75% of the laboratories met the biological variation-based quality specifications for glucose, cholesterol and HDL-cholesterol. Slightly over 50% of the laboratories met the analytical goal for HBA1c. Only one analyte (cholesterol) had a performance achieving the higher quality specifications consistent with 5σ. Our data from IQC do not consistently demonstrate that the results from clinical laboratories meet evidence-based quality specifications. Therefore, we propose that a graded scale of quality specifications may be needed at this stage.
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Quality indicators in inflammatory bowel disease.
Berry, Sameer K; Melmed, Gil Y
2018-01-01
Inflammatory bowel disease (IBD), which includes Crohn's disease and ulcerative colitis, is a chronic, debilitating, and expensive condition affecting millions of people globally. There is significant variation in the quality of care for patients with IBD across North America, Europe, and Asia; this variation suggests poor quality of care due to overuse, underuse, or misuse of health services and disparity of outcomes. Several initiatives have been developed to reduce variation in care delivery and improve processes of care, patient outcomes, and reduced healthcare costs. These initiatives include the development of quality indicator sets to standardize care across organizations, and learning health systems to enable data sharing between doctors and patients, and sharing of best practices among providers. These programs have been variably successful in improving patient outcomes and reducing healthcare utilization. Further studies are needed to demonstrate the long-term impact and applicability of these efforts in different geographic areas around the world, as regional variations in patient populations, societal preferences, and costs should inform local quality improvement efforts.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Landis, E.R.; Rohrbacher, T.J.; Gluskoter, H.
1999-07-01
As part of the activities conducted under the U.S. Hungarian Science and Technology Fund, a total of 39 samples from five coal mines in Hungary were selected for standard coal analyses and major, minor and trace elements analysis. The mine areas sampled were selected to provide a spectrum of coal quality information for comparison with other coal areas in central Europe and worldwide. All of the areas are of major importance in the energy budget of Hungary. The five sample sites contain coal in rocks of Jurassic, Cretaceous, Eocene, Miocene, and Pliocene age. The coals, from four underground and onemore » surface mine, range in rank from high volatile bituminous to lignite B. Most of the coal produced from the mines sampled is used to generate electricity. Some of the power plants that utilize the coals also provide heat for domestic and process usage. The standard coal analysis program is based on tests performed in accordance with standards of the American Society for Testing and Materials (ASTM). Proximate and ultimate analyses were supplemented by determinations of the heating value, equilibrium moisture, forms of sulfur, free-swelling index, ash fusion temperatures (both reducing and oxidizing), apparent specific gravity and Hardgrove Grindability index. The major, minor and trace element analyses were performed in accordance with standardized procedures of the U.S. Geological Survey. The analytical results will be available in the International Coal Quality Data Base of the USGS. The results of the program provide data for comparison with test data from Europe and information of value to potential investors or cooperators in the coal industry of Hungary and Central Europe.« less
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Weaver, Kimberly N; Kappelman, Michael D; Sandler, Robert S; Martin, Christopher F; Chen, Wenli; Anton, Kristen; Long, Millie D
2016-11-01
As variation in care has previously been linked to quality, we aimed to describe variations in inflammatory bowel diseases care by gastroenterology (GI) practice setting. We performed a cross-sectional study within the Crohn's and Colitis Foundation of America Partners and used bivariate analyses to compare patient characteristics by GI practice setting (GI-academic [GIA], GI-private, or GI-other). Regression models were used to describe the effects of provider type on steroid use, disease activity, and the quality of life. The study included 12,083 patients with inflammatory bowel diseases (7576 with Crohn's disease [CD] and 4507 with ulcerative colitis [UC]). Nearly 95% reported visiting a GI provider annually. Also, CD patients seen by GIA were younger, better educated, used less 5-aminosalicylate agents, and had higher biologic and immunomodulator use (P < 0.001 for all). On multivariate analysis of CD patients, GIA used less steroids when compared with GI-private (odds ratio, 0.84; 95% confidence interval, 0.67-1.06) or GI-other (odds ratio, 0.66; 95% confidence interval, 0.49-0.89). GIA patients were more likely to be in remission, have flu vaccine, and have better quality of life. UC patients seen by GIA were younger, had more hospitalizations, and previous surgery (P < 0.001 for all). No differences existed for steroid use, remission, flu vaccine, or quality of life for UC care on bivariate or multivariate analyses. Significant variations in care patterns and quality measures exist for CD across GI provider types, without similar variation in UC care. Interventions to reduce variations in care could improve the quality of care in CD.
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Litter quality versus soil microbial community controls over decomposition: a quantitative analysis
Cleveland, Cory C.; Reed, Sasha C.; Keller, Adrienne B.; Nemergut, Diana R.; O'Neill, Sean P.; Ostertag, Rebecca; Vitousek, Peter M.
2014-01-01
The possible effects of soil microbial community structure on organic matter decomposition rates have been widely acknowledged, but are poorly understood. Understanding these relationships is complicated by the fact that microbial community structure and function are likely to both affect and be affected by organic matter quality and chemistry, thus it is difficult to draw mechanistic conclusions from field studies. We conducted a reciprocal soil inoculum × litter transplant laboratory incubation experiment using samples collected from a set of sites that have similar climate and plant species composition but vary significantly in bacterial community structure and litter quality. The results showed that litter quality explained the majority of variation in decomposition rates under controlled laboratory conditions: over the course of the 162-day incubation, litter quality explained nearly two-thirds (64 %) of variation in decomposition rates, and a smaller proportion (25 %) was explained by variation in the inoculum type. In addition, the relative importance of inoculum type on soil respiration increased over the course of the experiment, and was significantly higher in microcosms with lower litter quality relative to those with higher quality litter. We also used molecular phylogenetics to examine the relationships between bacterial community composition and soil respiration in samples through time. Pyrosequencing revealed that bacterial community composition explained 32 % of the variation in respiration rates. However, equal portions (i.e., 16 %) of the variation in bacterial community composition were explained by inoculum type and litter quality, reflecting the importance of both the meta-community and the environment in bacterial assembly. Taken together, these results indicate that the effects of changing microbial community composition on decomposition are likely to be smaller than the potential effects of climate change and/or litter quality changes in response to increasing atmospheric CO2 concentrations or atmospheric nutrient deposition.
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Variations in the service quality of medical practices.
Ly, Dan P; Glied, Sherry A
2013-11-01
To examine regional variation in the service quality of physician practices and to assess the association of this variation with the supply and organization of physicians. Secondary analyses of the Community Tracking Study (CTS) household and physician surveys. A total of 40,339 individuals who had seen a primary care physician because of an illness or injury and 17,345 generalist physicians across 4 survey time periods in 60 CTS sites were included. Service quality measures used were lag between making an appointment and seeing a physician, and wait time at the physician's office. Our supply measure was the physician-to-population ratio. Our organizational measure was the percentage of physicians in group practices. Multivariate regressions were performed to examine the relationship between service quality and the supply and organization of physicians. There was substantial variation in the service quality of physician visits across the country. For example, in 2003, the average wait time to see a doctor was 16 minutes in Milwaukee but more than 41 minutes in Miami; the average appointment lag for a sick visit in 2003 was 1.2 days in west-central Alabama but almost 6 days in Northwestern Washington. Service quality was not associated with the primary care physician-to-population ratio and had varying associations with the organization of practices. Cross-site variation in service quality of care in primary care has been large, persistent, and associated with the organization of practices. Areas with higher primary care physician-to-population ratios had longer, not shorter, appointment lags.
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Eliminating Undesirable Variation in Neonatal Practice: Balancing Standardization and Customization.
Balakrishnan, Maya; Raghavan, Aarti; Suresh, Gautham K
2017-09-01
Consistency of care and elimination of unnecessary and harmful variation are underemphasized aspects of health care quality. This article describes the prevalence and patterns of practice variation in health care and neonatology; discusses the potential role of standardization as a solution to eliminating wasteful and harmful practice variation, particularly when it is founded on principles of evidence-based medicine; and proposes ways to balance standardization and customization of practice to ultimately improve the quality of neonatal care. Copyright © 2017 Elsevier Inc. All rights reserved.
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Leslie, Andrew B; Glasspool, Ian; Herendeen, Patrick S; Ichinnorov, Niiden; Knopf, Patrick; Takahashi, Masamichi; Crane, Peter R
2013-12-01
Seed cone scales assigned to the genus Schizolepidopsis are widespread in Late Triassic to Cretaceous Eurasian deposits. They have been linked to the conifer family Pinaceae based on associated vegetative remains, but their exact affinities are uncertain. Recently discovered material from the Early Cretaceous of Mongolia reveals important new information concerning Schizolepidopsis cone scales and seeds, and provides support for a relationship between the genus and extant Pinaceae. Specimens were collected from Early Cretaceous (probable Aptian-Albian) lignite deposits in central Mongolia. Lignite samples were disaggregated, cleaned in hydrofluoric acid, and washed in water. Specimens were selected for further study using light and electron microscopy. Schizolepidopsis canicularis seed cones consist of loosely arranged, bilobed ovulate scales subtended by a small bract. A single inverted seed with an elongate micropyle is borne on each lobe of the ovulate scale. Each seed has a wing formed by the separation of the adaxial surface of the ovulate scale. Schizolepidopsis canicularis produced winged seeds that formed in a manner that is unique to Pinaceae among extant conifers. We do not definitively place this species in Pinaceae pending more complete information concerning its pollen cones and vegetative remains. Nevertheless, this material suggests that Schizolepidopsis may be important for understanding the early evolution of Pinaceae, and may potentially help reconcile the appearance of the family in the fossil record with results based on phylogenetic analyses of molecular data.
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USE OF COAL DRYING TO REDUCE WATER CONSUMED IN PULVERIZED COAL POWER PLANTS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Edward K. Levy; Nenad Sarunac; Harun Bilirgen
2006-03-01
U.S. low rank coals contain relatively large amounts of moisture, with the moisture content of subbituminous coals typically ranging from 15 to 30 percent and that for lignites from 25 and 40 percent. High fuel moisture has several adverse impacts on the operation of a pulverized coal generating unit, for it can result in fuel handling problems and it affects heat rate, stack emissions and maintenance costs. Theoretical analyses and coal test burns performed at a lignite fired power plant show that by reducing the fuel moisture, it is possible to improve boiler performance and unit heat rate, reduce emissionsmore » and reduce water consumption by the evaporative cooling tower. The economic viability of the approach and the actual impact of the drying system on water consumption, unit heat rate and stack emissions will depend critically on the design and operating conditions of the drying system. The present project evaluated the low temperature drying of high moisture coals using power plant waste heat to provide the energy required for drying. Coal drying studies were performed in a laboratory scale fluidized bed dryer to gather data and develop models on drying kinetics. In addition, analyses were carried out to determine the relative costs and performance impacts (in terms of heat rate, cooling tower water consumption and emissions) of drying along with the development of optimized drying system designs and recommended operating conditions.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Chapelle, F.H.; Zelibor, J.L. Jr.; Grimes, D.J.
Nineteen cores of unconsolidated Coastal Plain sediments obtained from depths of 14 to 182 m below land surface near Waldorf, Maryland, were collected and examined for metabolically active bacteria. The age of the sediments cored range from Miocene to Early Cretaceous. Acridine orange direct counts of total (viable and nonviable) bacteria in core subsamples ranged from 10/sup 8/ to 10/sup 4/ bacteria/g of dry sediment. Direct counts of viable bacteria ranged from 10/sup 6/ to 10/sup 3/ bacteria/g of dry sediment. Three cores contained viable methanogenic bacteria, and seven cores contained viable sulfate-reducing bacteria. The observed presence of bacteria inmore » these sediments suggest that hetrotrophic bacterial metabolism, with lignitic organic material as the primary substrate, is a plausible source of CO/sub 2/ to ground water. However, the possibility that abiotic processes also produce CO/sub 2/ cannot be rules out. Estimated rates of CO/sub 2/ production in the noncalcareous Magothy/Upper Patapsco and Lower Patapsco aquifers based on mass balance of dissolved inorganic carbon, ground water flow rates, and flow path segment lengths are in the range 10/sup -3/ to 10/sup -5/ mmol L/sup -1/ yr/sup -1/. Isotope balance calculations suggest that aquifer-generated CO/sub 2/ is much heavier isotopically ( approx. - 10 to + 5 per mil) than lignite ( approx. - 24 per mil) present in these sediments. This may reflect isotopic fractionation during methanogenesis and possibly other bacterially mediated processes.« less
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Characteristics and synergistic effects of co-combustion of carbonaceous wastes with coal.
Onenc, Sermin; Retschitzegger, Stefan; Evic, Nikola; Kienzl, Norbert; Yanik, Jale
2018-01-01
This study presents combustion behavior and emission results obtained for different fuels: poultry litter (PL) and its char (PLC), scrap tires (ST) and its char (STC) and blends of char/lignite (PLC/LIG and STC/LIG). The combustion parameters and emissions were investigated via a non-isothermal thermogravimetric method and experiments in a lab-scale reactor. Fuel indexes were used for the prediction of high temperature corrosion risks and slagging potentials of the fuels used. The addition of chars to lignite caused a lowering of the combustion reactivity (anti-synergistic effect). There was a linear correlation between the NO x emissions and the N content of the fuel. The form of S and the concentrations of alkali metals in the fuel had a strong effect on the extent of SO 2 emissions. The use of PL and PLC in blends reduced SO 2 emissions and sulphur compounds in the fly ash. The 2S/Cl ratio in the fuel showed that only PLC and STC/PLC would show a risk of corrosion during combustion. The ratio of basic to acidic oxides in fuel indicated that ST, STC and STC/LIG have low slagging potential. The molar (Si+P+K)/(Ca+Mg) ratio, which was used for PL, PLC and PLC containing blends, showed that the ash melting temperatures of these fuels would be higher than 1000 °C. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Cooper, Anne Marie; Hristovski, Kiril D; Möller, Teresia; Westerhoff, Paul; Sylvester, Paul
2010-11-15
This study investigates the impact of the type of virgin granular activated carbon (GAC) media used to synthesize iron (hydr)oxide nanoparticle-impregnated granular activated carbon (Fe-GAC) on its properties and its ability to remove arsenate and organic trichloroethylene (TCE) from water. Two Fe-GAC media were synthesized via a permanganate/ferrous ion synthesis method using bituminous and lignite-based virgin GAC. Data obtained from an array of characterization techniques (pore size distribution, surface charge, etc.) in correlation with batch equilibrium tests, and continuous flow modeling suggested that GAC type and pore size distribution control the iron (nanoparticle) contents, Fe-GAC synthesis mechanisms, and contaminant removal performances. Pore surface diffusion model calculations predicted that lignite Fe-GAC could remove ∼6.3 L g(-1) dry media and ∼4 L g(-1) dry media of water contaminated with 30 μg L(-1) TCE and arsenic, respectively. In contrast, the bituminous Fe-GAC could remove only ∼0.2 L/g dry media for TCE and ∼2.8 L/g dry media for As of the same contaminated water. The results show that arsenic removal capability is increased while TCE removal is decreased as a result of Fe nanoparticle impregnation. This tradeoff is related to several factors, of which changes in surface properties and pore size distributions appeared to be the most dominant. Copyright © 2010 Elsevier B.V. All rights reserved.
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Health impacts of coal and coal use: Possible solutions
Finkelman, R.B.; Orem, W.; Castranova, V.; Tatu, C.A.; Belkin, H.E.; Zheng, B.; Lerch, H.E.; Maharaj, S.V.; Bates, A.L.
2002-01-01
Coal will be a dominant energy source in both developed and developing countries for at least the first half of the 21st century. Environmental problems associated with coal, before mining, during mining, in storage, during combustion, and postcombustion waste products are well known and are being addressed by ongoing research. The connection between potential environmental problems with human health is a fairly new field and requires the cooperation of both the geoscience and medical disciplines. Three research programs that illustrate this collaboration are described and used to present a range of human health problems that are potentially caused by coal. Domestic combustion of coal in China has, in some cases, severely affected human health. Both on a local and regional scale, human health has been adversely affected by coals containing arsenic, fluorine, selenium, and possibly, mercury. Balkan endemic nephropathy (BEN), an irreversible kidney disease of unknown origin, has been related to the proximity of Pliocene lignite deposits. The working hypothesis is that groundwater is leaching toxic organic compounds as it passes through the lignites and that these organics are then ingested by the local population contributing to this health problem. Human disease associated with coal mining mainly results from inhalation of particulate matter during the mining process. The disease is Coal Worker's Pneumoconiosis characterized by coal dust-induced lesions in the gas exchange regions of the lung; the coal worker's "black lung disease". ?? 2002 Elsevier Science B.V. All rights reserved.
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Filter materials for metal removal from mine drainage--a review.
Westholm, Lena Johansson; Repo, Eveliina; Sillanpää, Mika
2014-01-01
A large number of filter materials, organic and inorganic, for removal of heavy metals in mine drainage have been reviewed. Bark, chitin, chitosan, commercial ion exchangers, dairy manure compost, lignite, peat, rice husks, vegetal compost, and yeast are examples of organic materials, while bio-carbons, calcareous shale, dolomite, fly ash, limestone, olivine, steel slag materials and zeolites are examples of inorganic materials. The majority of these filter materials have been investigated in laboratory studies, based on various experimental set-ups (batch and/or column tests) and different conditions. A few materials, for instance steel slag materials, have also been subjects to field investigations under real-life conditions. The results from these investigations show that steel slag materials have the potential to remove heavy metals under different conditions. Ion exchange has been suggested as the major metal removal mechanisms not only for steel slag but also for lignite. Other suggested removal mechanisms have also been identified. Adsorption has been suggested important for activated carbon, precipitation for chitosan and sulphate reduction for olivine. General findings indicate that the results with regard to metal removal vary due to experimental set ups, composition of mine drainage and properties of filter materials and the discrepancies between studies renders normalisation of data difficult. However, the literature reveals that Fe, Zn, Pb, Hg and Al are removed to a large extent. Further investigations, especially under real-life conditions, are however necessary in order to find suitable filter materials for treatment of mine drainage.
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Human Variome Project Quality Assessment Criteria for Variation Databases.
Vihinen, Mauno; Hancock, John M; Maglott, Donna R; Landrum, Melissa J; Schaafsma, Gerard C P; Taschner, Peter
2016-06-01
Numerous databases containing information about DNA, RNA, and protein variations are available. Gene-specific variant databases (locus-specific variation databases, LSDBs) are typically curated and maintained for single genes or groups of genes for a certain disease(s). These databases are widely considered as the most reliable information source for a particular gene/protein/disease, but it should also be made clear they may have widely varying contents, infrastructure, and quality. Quality is very important to evaluate because these databases may affect health decision-making, research, and clinical practice. The Human Variome Project (HVP) established a Working Group for Variant Database Quality Assessment. The basic principle was to develop a simple system that nevertheless provides a good overview of the quality of a database. The HVP quality evaluation criteria that resulted are divided into four main components: data quality, technical quality, accessibility, and timeliness. This report elaborates on the developed quality criteria and how implementation of the quality scheme can be achieved. Examples are provided for the current status of the quality items in two different databases, BTKbase, an LSDB, and ClinVar, a central archive of submissions about variants and their clinical significance. © 2016 WILEY PERIODICALS, INC.
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Hosogaya, Shigemi; Ozaki, Yukio
2005-06-01
Many external quality assessment schemes (EQAS) are performed to support quality improvement of the services provided by participating laboratories for the benefits of patients. The EQAS organizer shall be responsible for ensuring that the method of evaluation is appropriate for maintenance of the credibility of the schemes. Procedures to evaluate each participating laboratory are gradually being standardized. In most cases of EQAS, the peer group mean is used as a target of accuracy, and the peer group standard deviation is used as a criterion for inter-laboratory variation. On the other hand, Fraser CG, et al. proposed desirable quality specifications for any imprecision and inaccuracies, which were derived from inter- and intra-biologic variations. We also proposed allowable limits of analytical error, being less than one-half of the average intra-individual variation for evaluation of imprecision, and less than one-quarter of the inter- plus intra-individual variation for evaluation of inaccuracy. When expressed in coefficient of variation terms, these allowable limits may be applied at a wide range of levels of quantity.
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Downing, Nicholas S; Wang, Yongfei; Dharmarajan, Kumar; Nuti, Sudhakar V; Murugiah, Karthik; Du, Xue; Zheng, Xin; Li, Xi; Li, Jing; Masoudi, Frederick A; Spertus, John A; Jiang, Lixin; Krumholz, Harlan M
2017-06-23
China has gaps in the quality of care provided to patients with ST-elevation myocardial infarction, but little is known about how quality varies between hospitals. Using nationally representative data from the China PEACE-Retrospective AMI Study, we characterized the quality of care for ST-elevation myocardial infarction at the hospital level and examined variation between hospitals. Two summary measures were used to describe the overall quality of care at each hospital and to characterize variations in quality between hospitals in 2001, 2006, and 2011. The composite rate measured the proportion of opportunities a hospital had to deliver 6 guideline-recommended treatments for ST-elevation myocardial infarction that were successfully met, while the defect-free rate measured the proportion of patients at each hospital receiving all guideline-recommended treatments for which they were eligible. Risk-standardized mortality rates were calculated. Our analysis included 12 108 patients treated for ST-elevation myocardial infarction at 162 hospitals. The median composite rate increased from 56.8% (interquartile range [IQR], 45.9-72.0) in 2001 to 80.5% (IQR, 74.7-84.8) in 2011; however, substantial variation remained in 2011 with defect-free rates ranging from 0.0% to 76.9%. The median risk-standardized mortality rate increased from 9.9% (IQR, 9.1-11.7) in 2001 to 12.6% (IQR, 10.9-14.6) in 2006 before falling to 10.4% (IQR, 9.1-12.4) in 2011. Higher rates of guideline-recommended care and a decline in variation between hospitals are indicative of an improvement in quality. Although some variation persisted in 2011, very top-performing hospitals missed few opportunities to provide guideline-recommended care. Quality improvement initiatives should focus on eliminating residual variation as well as measuring and improving outcomes. URL: https://www.clinicaltrials.gov. Unique identifier: NCT01624883. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.
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Quality variations in black musli (curculigo orchioides gaertn.).
Mathew, P P Joy Samuel; Savithri, K E; Skaria, Baby P; Kurien, Kochurani
2004-07-01
Black musli (Curculigo orchioides Gaertn.) one of the ayurvedic dasapushpa and a rejuvenating and aphrodisiac drug. Is on the verge of extinction and needs to be conserved and cultivated. Large variations are also observed in the quality of the crude drug available in the market. Study on the quality of C. orchioides in natural habitat, under cultivation and in trade in south India showed that there was considerable variation with biotypes and habitats. Drugs collected form the natural habitat was superior in quality to that produced by cultivation. Among the market samples collected from the various Zones of kerala, those from the High Ranges were superior in most of the quality parameters, which indicated its superiority for high quality drug formulation. Among the southern states, Tamil Nadu samples ranked next to High Range samples in this respect. There exists large variability in the market samples and there is felt-need for proper standardization of the crude drug for ensuring quality in the drug formulations.
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Seasonal variations on sugarcane trash quantity and quality that directly concern refiners
USDA-ARS?s Scientific Manuscript database
There is a trend in the U.S. and world-wide to produce very high pol (VHP) and very low color (VLC) raw sugars for vertical integration from the field to the refinery. Great variations in the color and quality of raw and VHP/VLC sugars exist mostly because of the range in quality of the cane supply...
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Organic pollutants removal from 2,4,6-trinitrotoluene (TNT) red water using low cost activated coke.
Zhang, Mohe; Zhao, Quanlin; Ye, Zhengfang
2011-01-01
We treated 2,4,6-trinitrotoluene (TNT) red water from the Chinese explosive industry with activated coke (AC) from lignite. Since the composition of TNT red water was very complicated, chemical oxygen demand (COD) was used as the index for evaluating treatment efficiency. This study focused on sorption kinetics and equilibrium sorption isotherms of AC for the removal of COD from TNT red water, and the changes of water quality before and after adsorption were evaluated using high performance liquid chromatography, UV-Vis spectra and gas chromatography/mass spectroscopy. The results showed that the sorption kinetics of COD removal from TNT red water onto AC fitted well with the pseudo second-order model. The adsorption process was an exothermic and physical process. The sorption isotherm was in good agreement with Redlich-Peterson isotherm. At the conditions of initial pH = 6.28, 20 degrees C and 3 hr of agitation, under 160 g/L AC, 64.8% of COD was removed. The removal efficiencies of 2,4-dinitrotoluene-3-sulfonate (2,4-DNT-3-SO3-) and 2,4-dinitrotoluene-5-sulfonate (2,4-DNT-5-SO3-) were 80.5% and 84.3%, respectively. After adsorption, the acute toxicity of TNT red water reduced greatly, compared with that of unprocessed TNT red water.
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NASA Astrophysics Data System (ADS)
Wang, Haixia; Suo, Tongchuan; Wu, Xiaolin; Zhang, Yue; Wang, Chunhua; Yu, Heshui; Li, Zheng
2018-03-01
The control of batch-to-batch quality variations remains a challenging task for pharmaceutical industries, e.g., traditional Chinese medicine (TCM) manufacturing. One difficult problem is to produce pharmaceutical products with consistent quality from raw material of large quality variations. In this paper, an integrated methodology combining the near infrared spectroscopy (NIRS) and dynamic predictive modeling is developed for the monitoring and control of the batch extraction process of licorice. With the spectra data in hand, the initial state of the process is firstly estimated with a state-space model to construct a process monitoring strategy for the early detection of variations induced by the initial process inputs such as raw materials. Secondly, the quality property of the end product is predicted at the mid-course during the extraction process with a partial least squares (PLS) model. The batch-end-time (BET) is then adjusted accordingly to minimize the quality variations. In conclusion, our study shows that with the help of the dynamic predictive modeling, NIRS can offer the past and future information of the process, which enables more accurate monitoring and control of process performance and product quality.
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Designing a system for measuring the flow of material transported on belts using ultrasonic sensors
NASA Astrophysics Data System (ADS)
Mihuţ, N. M.
2015-11-01
Excavation tailings (scraping) and extracting the useful (lignite) in surface mine pits in Mining Basin Oltenia is achieved with technological lines of excavation - transport - dump of high productivity. A correlation of working capacity of the main components of technological lines (motor rotor, high capacity transport, car dumps) is necessary for economic reasons on electricity consumption. To achieve experience in the process was chosen excavator SRS 1400 from South Jilt career in the CET Turceni. The question of coal excavated volume has a great importance in the mine pits. At the excavation is desired a density estimate for each machine production tracking, cost estimation and tracking product unit profitability of each band on various sections zones. Permanent display size excavated volume snapshots in the excavator's cabin permits to track tape loading, eliminating unproductive times and information management to determine profitability. Another important requirement is closing the loop of the machine drive system of an excavator for a uniform deposition of carbon on the strip, thus achieving automatic control of the loading belt. Such equipment is important for the system dispatching in surface mine pits. Through a system of three ultrasound transducers to determine the smart instant of coal excavated section which, coupled with the tape speed, integrated over time will determine the amount of excavated coal. The basis of the system developed is a device for determining the volume and quantity of coal excavated acting on the march and optimize the system speed excavator working order. The device is designed primarily following the careers of lignite production: rotor excavators, rubber conveyor belts and dump facilities. Newly developed system aims to achieve the following determines: the optimum energy excavation depending on the nature of excavated material - lignite, shale, clay, etc., economic times to use the excavator bucket teeth rotor, energy optical regime to rubber belt conveyors, eliminate damage to the plant by conveyor belt breakage detection or tread and eliminating time and energy losses by limiting reproductive idle, monitoring the amount of coal excavated, control power consumption. Systems in general and particularly automated systems cannot be designed without taking into account their degree of effectiveness, compliance with minimum consumption of time, energy and materials, insofar as they are requested and used all the resources it has, at minimum cost production, etc. For this reason any matter of calculation, design, analysis and operation of transport systems continuously subordinate requirements optimality.
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Field Testing of a Wet FGD Additive for Enhanced Mercury Control - Pilot-Scale Test Results
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gary M. Blythe
2006-03-01
This Topical Report summarizes progress on Cooperative Agreement DE-FC26-04NT42309, ''Field Testing of a Wet FGD Additive.'' The objective of the project is to demonstrate the use of a flue gas desulfurization (FGD) additive, Degussa Corporation's TMT-15, to prevent the reemissions of elemental mercury (Hg{sup 0}) in flue gas exiting wet FGD systems on coal-fired boilers. Furthermore, the project intends to demonstrate that the additive can be used to precipitate most of the mercury (Hg) removed in the wet FGD system as a fine TMT salt that can be separated from the FGD liquor and bulk solid byproducts for separate disposal.more » The project will conduct pilot and full-scale tests of the TMT-15 additive in wet FGD absorbers. The tests are intended to determine required additive dosage requirements to prevent Hg{sup 0} reemissions and to separate mercury from the normal FGD byproducts for three coal types: Texas lignite/Power River Basin (PRB) coal blend, high-sulfur Eastern bituminous coal, and low-sulfur Eastern bituminous coal. The project team consists of URS Group, Inc., EPRI, TXU Generation Company LP, Southern Company, and Degussa Corporation. TXU Generation has provided the Texas lignite/PRB co-fired test site for pilot FGD tests, Monticello Steam Electric Station Unit 3. Southern Company is providing the low-sulfur Eastern bituminous coal host site for wet scrubbing tests, as well as the pilot and full-scale jet bubbling reactor (JBR) FGD systems to be tested. A third utility, to be named later, will provide the high-sulfur Eastern bituminous coal full-scale FGD test site. Degussa Corporation is providing the TMT-15 additive and technical support to the test program. The project is being conducted in six tasks. Of the six project tasks, Task 1 involves project planning and Task 6 involves management and reporting. The other four tasks involve field testing on FGD systems, either at pilot or full scale. The four tasks include: Task 2 - Pilot Additive Testing in Texas Lignite Flue Gas; Task 3 - Full-scale FGD Additive Testing in High Sulfur Eastern Bituminous Flue Gas; Task 4 - Pilot Wet Scrubber Additive Tests at Yates; and Task 5 - Full-scale Additive Tests at Plant Yates. This topical report presents the results from the Task 2 and Task 4 pilot-scale additive tests. The Task 3 and Task 5 full-scale additive tests will be conducted later in calendar year 2006.« less
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Thorium and Uranium in the Rock Raw Materials Used For the Production of Building Materials
NASA Astrophysics Data System (ADS)
Pękala, Agnieszka
2017-10-01
Thorium and uranium are constant components of all soils and most minerals thereby rock raw materials. They belong to the particularly dangerous elements because of their natural radioactivity. Evaluation of the content of the radioactive elements in the rock raw materials seems to be necessary in the early stage of the raw material evaluation. The rock formations operated from deposits often are accumulated in landfills and slag heaps where the concentration of the radioactive elements can be many times higher than under natural conditions. In addition, this phenomenon may refer to buildings where rock raw materials are often the main components of the construction materials. The global control system of construction products draws particular attention to the elimination of used construction products containing excessive quantities of the natural radioactive elements. In the presented study were determined the content of thorium and uranium in rock raw materials coming from the Bełachatów lignite deposit. The Bełchatów lignite deposit extracts mainly lignite and secondary numerous accompanying minerals with the raw material importance. In the course of the field works within the framework of the carried out work has been tested 92 samples of rocks of varied petrographic composition. There were carried out analyses of the content of the radioactive elements for 50 samples of limestone of the Jurassic age, 18 samples of kaolinite clays, and 24 samples of siliceous raw materials, represented by opoka-rocks, diatomites, gaizes and clastic rocks. The measurement of content of the natural radioactive elements thorium and uranium based on measuring the frequency counts of gamma quantum, recorded separately in measuring channels. At the same time performed measurements on volume patterns radioactive: thorium and uranium. The studies were carried out in Mazar spectrometer on the powdered material. Standardly performed ten measuring cycles, after which were calculated the concentration of radioactive elements in the sample. The highest concentration of thorium and uranium has been found in the clayey raw material. Their value was respectively from 8 to 12 mg/kg for thorium and from 2.3 to 3.5 mg/kg for uranium. In carbonate sediments the content of thorium was at the level from 0.5 to 2.1 mg/kg and uranium from 0.5-2.2 mg/kg. From a group of the siliceous raw materials the diatomite had a highest concentrations of radioactive elements where the content of thorium was from 1.5 to 1.8 mg/kg and uranium from 1.3 to 1.7 mg/kg.
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Health System Perspective: Variation, Costs, and Physician Behavior.
Jevsevar, David S
2015-01-01
With the generalized rise in cost of US health care, renewed emphasis has been placed on defining the relationship between costs and outcome. The quality of health care delivery has been uneven, as measured by existing quality and performance measures, significant variation in the delivery of care, lack of standardization of care leading to avoidable error, lack of meaningful outcomes measurement, and apparent disconnect with cost. Orthopaedic surgeons are at the nexus of implementing change, as we are the primary decision makers regarding care of our patients. This summary will review efforts that address quality, cost, outcome, safety, and variation in care.
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Withered on the stem: is bamboo a seasonally limiting resource for giant pandas?
Li, Youxu; Swaisgood, Ronald R; Wei, Wei; Nie, Yonggang; Hu, Yibo; Yang, Xuyu; Gu, Xiaodong; Zhang, Zejun
2017-04-01
In response to seasonal variation in quality and quantity of available plant biomass, herbivorous foragers may alternate among different plant resources to meet nutritional requirements. Giant pandas (Ailuropoda melanoleuca) are reliant almost exclusively on bamboo which appears omnipresent in most occupied habitat, but subtle temporal variation in bamboo quality may still govern foraging strategies, with population-level effects. In this paper, we investigated the possibility that temporal variation in the quality of this resource is involved in population regulation and examined pandas' adaptive foraging strategies in response to temporal variation in bamboo quality. Giant pandas in late winter and early spring consumed a less optimal diet in Foping Nature Reserve, as the availability of the most nutritious and preferred components and age classes of Bashania fargesii declined, suggesting that bamboo may be a seasonally limiting resource. Most panda mortalities and rescues occurred during the same period of seasonal food limitation. Our findings raised the possibility that while total bamboo biomass may not be a limiting factor, carrying capacity may be influenced by subtle seasonal variation in bamboo quality. We recommend that managers and policy-makers should consider more than just the quantity of bamboo in the understory and that carrying capacity estimates should be revised downward to reflect the fact that all bamboos are not equal.
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NASA Astrophysics Data System (ADS)
Sinha, Amit Kumar; Kim, Duck Young; Ceglarek, Darek
2013-10-01
Many advantages of laser welding technology such as high speed and non-contact welding make the use of the technology more attractive in the automotive industry. Many studies have been conducted to search the optimal welding condition experimentally that ensure the joining quality of laser welding that relies both on welding system configuration and welding parameter specification. Both non-destructive and destructive techniques, for example, ultrasonic inspection and tensile test are widely used in practice for estimating the joining quality. Non-destructive techniques are attractive as a rapid quality testing method despite relatively low accuracy. In this paper, we examine the relationship between the variation of weld seam and tensile shear strength in the laser welding of galvanized steel in a lap joint configuration in order to investigate the potential of the variation of weld seam as a joining quality estimator. From the experimental analysis, we identify a trend in between maximum tensile shear strength and the variation of weld seam that clearly supports the fact that laser welded parts having larger variation in the weld seam usually have lower tensile strength. The discovered relationship leads us to conclude that the variation of weld seam can be used as an indirect non-destructive testing method for estimating the tensile strength of the welded parts.
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Groundwater Quality: Analysis of Its Temporal and Spatial Variability in a Karst Aquifer.
Pacheco Castro, Roger; Pacheco Ávila, Julia; Ye, Ming; Cabrera Sansores, Armando
2018-01-01
This study develops an approach based on hierarchical cluster analysis for investigating the spatial and temporal variation of water quality governing processes. The water quality data used in this study were collected in the karst aquifer of Yucatan, Mexico, the only source of drinking water for a population of nearly two million people. Hierarchical cluster analysis was applied to the quality data of all the sampling periods lumped together. This was motivated by the observation that, if water quality does not vary significantly in time, two samples from the same sampling site will belong to the same cluster. The resulting distribution maps of clusters and box-plots of the major chemical components reveal the spatial and temporal variability of groundwater quality. Principal component analysis was used to verify the results of cluster analysis and to derive the variables that explained most of the variation of the groundwater quality data. Results of this work increase the knowledge about how precipitation and human contamination impact groundwater quality in Yucatan. Spatial variability of groundwater quality in the study area is caused by: a) seawater intrusion and groundwater rich in sulfates at the west and in the coast, b) water rock interactions and the average annual precipitation at the middle and east zones respectively, and c) human contamination present in two localized zones. Changes in the amount and distribution of precipitation cause temporal variation by diluting groundwater in the aquifer. This approach allows to analyze the variation of groundwater quality controlling processes efficiently and simultaneously. © 2017, National Ground Water Association.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
The report presents the results of a study prepared by Burns and Roe for the Electricity Generating Authority of Thailand to examine the technical feasibility and economic attractiveness for building a 50 MW Atmospheric Fluidized Bed Combustion lignite fired power plant at Krabi, southern Thailand. The study is divided into seven main sections, plus an executive summary and appendices: (1) Introduction; (2) Atmospheric Fluidized Bed Combustion Technology Overview; (3) Fuel and Limestone Tests; (4) Site Evaluation; (5) Station Design and Arrangements; (6) Environmental Considerations; (7) Economic Analysis.
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Electric Pulse Discharge Activated Carbon Supercapacitors for Transportation Application
NASA Astrophysics Data System (ADS)
Nayak, Subhadarshi; Agrawal, Jyoti
2012-03-01
ScienceTomorrow is developing a high-speed, low-cost process for synthesizing high-porosity electrodes for electrochemical double-layer capacitors. Four types of coal (lignite, subbituminous, bituminous, and anthracite) were used as precursor materials for spark discharge activation with multiscale porous structure. The final porosity and pore distribution depended, among other factors, on precursor type. The high gas content in low-grade carbon resulted in mechanical disintegration, whereas high capacitance was attained in higher-grade coal. The properties, including capacitance, mechanical robustness, and internal conductivity, were excellent when the cost is taken into consideration.
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Rettman, Paul
1981-01-01
The delineation of the water table in the alluvium of the Colorado River is fairly well defined, and 10-feet contour intervals may be interpreted with confidence in the area called ' potential lignite-mining area. ' The water table in the bedrock aquifers is more difficult to delineate with the available data; therefore, the contours are only estimates of the position of the water table in the hilly bedrock area adjacent to the Colorado River alluvium.
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DeBarr, Joseph A.; Lizzio, Anthony A.; Daley, Michael A.
1996-01-01
Carbon-based materials are used commercially to remove SO2 from coal combustion flue gases. Historically, these materials have consisted of granular activated carbons prepared from lignite or bituminous coal. Recent studies have reported that activated carbon fibers (ACFs) may have potential in this application due to their relatively high SO2 adsorption capacity. In this paper, a comparison of SO2 adsorption for both coal-based carbons and ACFs is presented, as well as ideas on carbon properties that may influence SO2 adsorption
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Waterborne Commerce of the United States, Calendar Year 1985. Part 5. National Summaries.
1987-05-01
raomts the perfomsac* of the water carrier industry in toerm of con-miles on a typo of service basis a"d provides detailed data on typos of traffic and...Group 24-Lumber and Wood Products 1Ml Coal and lignite Except furniture Group 13-Crude Petroleum 2411 Logs 2412 Rafted logs 1311 Crude petroleum 2413...7.8 percent in 1985. 19 5 amonted to 1,788.4 million tons. a decrease of Export. to Candian Great Lakes ports decreased 4.617.6 million tone
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Yilmaz, A.O.; Aydiner, K.
Lignite and hard coal are the major sources of domestic energy sources of Turkey. Hard coal is produced at only one district in the country. Zonguldak Hard Coal Basin is the major power for development of the Turkish steel-making industry. It is the only hard coal basin in the country and it has, to date, supplied approximately 400 million tons of run-of-mine hard coal. This article investigates the potential of hard coal as an energy source and discusses the measures to activate the region for the future energy supply objectives of the country.
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Samuels, Mary H; Kaimal, Rajani; Waring, Avantika; Fink, Howard A; Yaffe, Kristine; Hoffman, Andrew R; Orwoll, Eric; Bauer, Douglas
2016-09-01
Variations in thyroid function within the laboratory reference range have been associated with a number of clinical outcomes. However, quality of life, mood, and cognitive function have not been extensively studied, and it is not clear whether mild variations in thyroid function have major effects on these neurocognitive outcomes. Data were analyzed from the Osteoporotic Fractures in Men (MrOS) Study, a cohort of community-dwelling men aged 65 years and older in the United States. A total of 539 participants who were not taking thyroid medications and had age-adjusted TSH levels within the reference range underwent detailed testing of quality of life, mood, and cognitive function at baseline. The same quality of life, mood, and cognitive outcomes were measured again in 193 of the men after a mean follow-up of 6 years. Outcomes were analyzed using thyrotropin (TSH) and free thyroxine (FT4) levels as continuous independent variables, adjusting for relevant covariates. At baseline, there were no associations between TSH or FT4 levels and measures of quality of life, mood, or cognition in the 539 euthyroid men. Baseline thyroid function did not predict changes in these outcomes over a mean of 6 years in the 193 men in the longitudinal analysis. Variations in thyroid function within the age-adjusted laboratory reference range are not associated with variations in quality of life, mood, or cognitive function in community-dwelling older men.
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Freeman, Kathleen P; Baral, Randolph M; Dhand, Navneet K; Nielsen, Søren Saxmose; Jensen, Asger L
2017-06-01
The recent creation of a veterinary clinical pathology biologic variation website has highlighted the need to provide recommendations for future studies of biologic variation in animals in order to help standardize and improve the quality of published information and to facilitate review and selection of publications as standard references. The following recommendations are provided in the format and order commonly found in veterinary publications. A checklist is provided to aid in planning, implementing, and evaluating veterinary studies on biologic variation (Appendix S1). These recommendations provide a valuable resource for clinicians, laboratorians, and researchers interested in conducting studies of biologic variation and in determining the quality of studies of biologic variation in veterinary laboratory testing. © 2017 American Society for Veterinary Clinical Pathology.
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[Comparative quality measurements part 3: funnel plots].
Kottner, Jan; Lahmann, Nils
2014-02-01
Comparative quality measurements between organisations or institutions are common. Quality measures need to be standardised and risk adjusted. Random error must also be taken adequately into account. Rankings without consideration of the precision lead to flawed interpretations and enhances "gaming". Application of confidence intervals is one possibility to take chance variation into account. Funnel plots are modified control charts based on Statistical Process Control (SPC) theory. The quality measures are plotted against their sample size. Warning and control limits that are 2 or 3 standard deviations from the center line are added. With increasing group size the precision increases and so the control limits are forming a funnel. Data points within the control limits are considered to show common cause variation; data points outside special cause variation without the focus of spurious rankings. Funnel plots offer data based information about how to evaluate institutional performance within quality management contexts.
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Karlsson, Maria A; Langton, Maud; Innings, Fredrik; Wikström, Malin; Lundh, Åse Sternesjö
2017-04-01
The composition and properties of raw milk are of great importance for the quality and shelf life of the final dairy product, especially in products with a long shelf life [e.g., ultra-high-temperature (UHT)-treated milk]. The objective of this study was to investigate the compositional variation in raw milk samples before processing at the dairy plant. Moreover, we wanted to investigate the effect of the UHT process on this variation (i.e., if the same variation could be observed in the corresponding UHT milk). The quality traits analyzed included detailed milk composition, counts of total and psychrotrophic bacteria, proteolytic activity, and color, as well as predictive measures of stability (i.e., ethanol stability and heat coagulating time). Samples of raw milk and the corresponding produced UHT milk were collected and analyzed on a monthly basis during 1 yr. Principal component analysis was used to identify months showing similarities and differences with respect to total variation. In contrast to previous studies, we observed only small variations between months and no clear effect of season for the raw milk. For the UHT milk, July and the winter months (December, January, and February) tended to separate from the other months. Quality traits showing significant variation were only to some extent identical in raw milk and UHT-processed milk. A better understanding of the natural variation in raw milk quality will provide opportunities to improve the shelf life of UHT-treated milk products. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
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Investigation of priorities in water quality management based on correlations and variations.
Boyacıoğlu, Hülya; Gündogdu, Vildan; Boyacıoğlu, Hayal
2013-04-15
The development of water quality assessment strategies investigating spatial and temporal changes caused by natural and anthropogenic phenomena is an important tool in management practices. This paper used cluster analysis, water quality index method, sensitivity analysis and canonical correlation analysis to investigate priorities in pollution control activities. Data sets representing 22 surface water quality parameters were subject to analysis. Results revealed that organic pollution was serious threat for overall water quality in the region. Besides, oil and grease, lead and mercury were the critical variables violating the standard. In contrast to inorganic variables, organic and physical-inorganic chemical parameters were influenced by variations in physical conditions (discharge, temperature). This study showed that information produced based on the variations and correlations in water quality data sets can be helpful to investigate priorities in water management activities. Moreover statistical techniques and index methods are useful tools in data - information transformation process. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Birditt, Kira S.; Hartnett, Caroline Sten; Fingerman, Karen L.; Zarit, Steven; Antonucci, Toni C.
2015-01-01
The intergenerational stake hypothesis suggests that parents are more invested in their children and experience better quality parent–child ties than do their children. In this study the authors examined variation in reports of relationship quality regarding parents and children intraindividually (do people report better quality ties with their children than with their parents?) and whether within-person variations have implications for well-being. Participants age 40–60 (N = 633) reported on their relationship quality (importance, positive and negative quality) with their parents and adult children. Individuals reported their relationships with children were more important and more negative than relationships with parents. Individuals with feelings that were in the opposite direction of the intergenerational stake hypothesis (i.e., greater investment in parents than children) reported poorer well-being. The findings provide support for the intergenerational stake hypothesis with regard to within-person variations in investment and show that negative relationship quality may coincide with greater feelings of investment. PMID:26339103
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Chen, Ming-Shu; Wu, Ming-Hsun; Lin, Chih-Ming
2014-04-30
The traditional criteria for acceptability of analytic quality may not be objective in clinical laboratories. To establish quality control procedures intended to enhance Westgard multi-rules for improving the quality of clinical biochemistry tests, we applied the Cp and Cpk quality-control indices to monitor tolerance fitting and systematic variation of clinical biochemistry test results. Daily quality-control data of a large Taiwanese hospital in 2009 were analyzed. The test items were selected based on an Olympus biochemistry machine and included serum albumin, aspartate aminotransferase, cholesterol, glucose and potassium levels. Cp and Cpk values were calculated for normal and abnormal levels, respectively. The tolerance range was estimated with data from 50 laboratories using the same instruments and reagents. The results showed a monthly trend of variation for the five items under investigation. The index values of glucose were lower than those of the other items, and their values were usually <2. In contrast to the Cp value for cholesterol, Cpk of cholesterol was lower than 2, indicating a systematic error that should be further investigated. This finding suggests a degree of variation or failure to meet specifications that should be corrected. The study indicated that Cp and Cpk could be applied not only for monitoring variations in quality control, but also for revealing inter-laboratory qualitycontrol capability differences.
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The offspring quantity–quality trade-off and human fertility variation
Lawson, David W.; Borgerhoff Mulder, Monique
2016-01-01
The idea that trade-offs between offspring quantity and quality shape reproductive behaviour has long been central to economic perspectives on fertility. It also has a parallel and richer theoretical foundation in evolutionary ecology. We review the application of the quantity–quality trade-off concept to human reproduction, emphasizing distinctions between clutch size and lifetime fertility, and the wider set of forces contributing to fertility variation in iteroparous and sexually reproducing species like our own. We then argue that in settings approximating human evolutionary history, several factors limit costly sibling competition. Consequently, while the optimization of quantity–quality trade-offs undoubtedly shaped the evolution of human physiology setting the upper limits of reproduction, we argue it plays a modest role in accounting for socio-ecological and individual variation in fertility. Only upon entering the demographic transition can fertility limitation be clearly interpreted as strategically orientated to advancing offspring quality via increased parental investment per child, with low fertility increasing descendant socio-economic success, although not reproductive success. We conclude that existing economic and evolutionary literature has often overemphasized the centrality of quantity–quality trade-offs to human fertility variation and advocate for the development of more holistic frameworks encompassing alternative life-history trade-offs and the evolved mechanisms guiding their resolution. PMID:27022072
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River water quality assessment using environmentric techniques: case study of Jakara River Basin.
Mustapha, Adamu; Aris, Ahmad Zaharin; Juahir, Hafizan; Ramli, Mohammad Firuz; Kura, Nura Umar
2013-08-01
Jakara River Basin has been extensively studied to assess the overall water quality and to identify the major variables responsible for water quality variations in the basin. A total of 27 sampling points were selected in the riverine network of the Upper Jakara River Basin. Water samples were collected in triplicate and analyzed for physicochemical variables. Pearson product-moment correlation analysis was conducted to evaluate the relationship of water quality parameters and revealed a significant relationship between salinity, conductivity with dissolved solids (DS) and 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), and nitrogen in form of ammonia (NH4). Partial correlation analysis (r p) results showed that there is a strong relationship between salinity and turbidity (r p=0.930, p=0.001) and BOD5 and COD (r p=0.839, p=0.001) controlling for the linear effects of conductivity and NH4, respectively. Principal component analysis and or factor analysis was used to investigate the origin of each water quality parameter in the Jakara Basin and identified three major factors explaining 68.11 % of the total variance in water quality. The major variations are related to anthropogenic activities (irrigation agricultural, construction activities, clearing of land, and domestic waste disposal) and natural processes (erosion of river bank and runoff). Discriminant analysis (DA) was applied on the dataset to maximize the similarities between group relative to within-group variance of the parameters. DA provided better results with great discriminatory ability using eight variables (DO, BOD5, COD, SS, NH4, conductivity, salinity, and DS) as the most statistically significantly responsible for surface water quality variation in the area. The present study, however, makes several noteworthy contributions to the existing knowledge on the spatial variations of surface water quality and is believed to serve as a baseline data for further studies. Future research should therefore concentrate on the investigation of temporal variations of water quality in the basin.
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MEASURING AND MODELING VARIATIONS IN DISTRIBUTION SYSTEM WATER QUALITY
The authors describe a field study that examined the effects of hydraulic mixing on water quality variations in a distribution system. Conducted at the North Penn Water Authority (average production of 5 mgd and 225 mi of distribution pipe), the study incorporated a field samplin...
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Evaluation of functional variation in candidate genes for pork quality
USDA-ARS?s Scientific Manuscript database
Considerable variation exists in pork quality traits and consumer perception of pork eating satisfaction is largely driven by tenderness and sensory juiciness scores, which are related to shear force, cooking loss and ultimate pH. Water loss from meat during postmortem storage reduces profitability ...
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Improvement of the quality of work in a biochemistry laboratory via measurement system analysis.
Chen, Ming-Shu; Liao, Chen-Mao; Wu, Ming-Hsun; Lin, Chih-Ming
2016-10-31
An adequate and continuous monitoring of operational variations can effectively reduce the uncertainty and enhance the quality of laboratory reports. This study applied the evaluation rule of the measurement system analysis (MSA) method to estimate the quality of work conducted in a biochemistry laboratory. Using the gauge repeatability & reproducibility (GR&R) approach, variations in quality control (QC) data among medical technicians in conducting measurements of five biochemical items, namely, serum glucose (GLU), aspartate aminotransferase (AST), uric acid (UA), sodium (Na) and chloride (Cl), were evaluated. The measurements of the five biochemical items showed different levels of variance among the different technicians, with the variances in GLU measurements being higher than those for the other four items. The ratios of precision-to-tolerance (P/T) for Na, Cl and GLU were all above 0.5, implying inadequate gauge capability. The product variation contribution of Na was large (75.45% and 31.24% in normal and abnormal QC levels, respectively), which showed that the impact of insufficient usage of reagents could not be excluded. With regard to reproducibility, high contributions (of more than 30%) of variation for the selected items were found. These high operator variation levels implied that the possibility of inadequate gauge capacity could not be excluded. The analysis of variance (ANOVA) of GR&R showed that the operator variations in GLU measurements were significant (F=5.296, P=0.001 in the normal level and F=3.399, P=0.015 in the abnormal level, respectively). In addition to operator variations, product variations of Na were also significant for both QC levels. The heterogeneity of variance for the five technicians showed significant differences for the Na and Cl measurements in the normal QC level. The accuracy of QC for five technicians was identified for further operational improvement. This study revealed that MSA can be used to evaluate product and personnel errors and to improve the quality of work in a biochemical laboratory through proper corrective actions.
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Yucel, Deniz Sanliyuksel; Baba, Alper
2013-04-01
Mining activity generates a large quantity of mine waste. The potential hazard of mine waste depends on the host mineral. The tendency of mine waste to produce acid mine drainage (AMD) containing potentially toxic metals depends on the amounts of sulfide, carbonate minerals, and trace-element concentrations found in ore deposits. The acid mine process is one of the most significant environmental challenges and a major source of water pollution worldwide. AMD and its effects were studied in northwest Turkey where there are several sedimentary and hydrothermal mineral deposits that have been economically extracted. The study area is located in Can county of Canakkale province. Canakkale contains marine, lagoon, and lake sediments precipitated with volcanoclastics that occurred as a result of volcanism, which was active during various periods from the Upper Eocene to Plio-Quaternary. Can county is rich in coal with a total lignite reserve >100 million tons and contains numerous mines that were operated by private companies and later abandoned without any remediation. As a result, human intervention in the natural structure and topography has resulted in large open pits and deterioration in these areas. Abandoned open pit mines typically fill with water from runoff and groundwater discharge, producing artificial lakes. Acid drainage waters from these mines have resulted in the degradation of surface-water quality around Can County. The average pH and electrical conductivity of acid mine lakes (AMLs) in this study were found to be 3.03 and 3831.33 μS cm(-1), respectively. Total iron (Fe) and aluminum (Al) levels were also found to be high (329.77 and 360.67 mg L(-1), respectively). The results show that the concentration of most elements, such as Fe and Al in particular, exceed national and international water-quality standards.
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Lenz, Bernard N.; Rheaume, S.J.
2000-01-01
This report describes the variability in family-level benthic-invertebrate population data and the reliability of the data as a water-quality indicator for 11 fixed surface-water sites in the Western Lake Michigan Drainages study area of the National Water-Quality Assessment Program. Benthic-invertebrate-community measures were computed for the following: number of individuals, Hilsenhoff’s Family-Level Biotic Index, number and percent EPT (Ephemeroptera, Plecoptera, and Tricoptera), Margalef’s Diversity Index, and mean tolerance value. Relations between these measures and environmental setting, habitat, and of chemical water quality are examined. Benthic-invertebrate communities varied greatly among fixed sites and within individual streams among multiple-reach and multiple-year sampling. The variations between multiple reaches and years were sometimes larger than those found between different fixed sites. Factors affecting benthic invertebrates included both habitat and chemical quality. Generally, fixed-site streams with the highest diversity, greatest number of benthic invertebrates, and those at which community measures indicated the best water quality also had the best habitat and chemical quality. Variations among reaches are most likely related to differences in habitat. Variations among years are most likely related to climatic changes, which create variations in flow and/or chemical quality. The variability in the data analyzed in this study shows how benthic invertebrates are affected by differences in both habitat and water quality, making them useful indicators of stream health; however, a single benthic-invertebrate sample alone cannot be relied upon to accurately describe water quality of the streams in this study. Benthic-invertebrate data contributed valuable information on the biological health of the 11 fixed sites when used as one of several data sources for assessing water quality.
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Rapid Assessment Of The Fundamental Property Variation Of Wood
Chi-Leung So; Leslie H. Groom; Timothy G. Rials; Rebecca Snell; Stephen S. Kelley; Robert Meglen
2002-01-01
Abstract - Genetic variation, site conditions, silvicultural treatments, seasonal effects, and their complex interaction are all vitally-important factors accounting for the variability and quality of the raw material produced - wood. Quality can be measured in several ways that generally influence the end use. The most desirable measure is the...
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Predictors of Between-Family and Within-Family Variation in Parent-Child Relationships
ERIC Educational Resources Information Center
O'Connor, Thomas G.; Dunn, Judy; Jenkins, Jennifer M.; Rasbash, Jon
2006-01-01
Background: Previous studies have found that multiple factors are associated with parent-child relationship quality, but have not distinguished potential sources of between-family and within-family variation in parent-child relationship quality. Methods: Approximately equal numbers of biological (non-stepfamilies), single-mother, stepfather, and…
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Individual differences, density dependence and offspring birth traits in a population of red deer
Stopher, Katie V; Pemberton, Josephine M; Clutton-Brock, Tim H; Coulson, Tim
2008-01-01
Variation between individuals is an essential component of natural selection and evolutionary change, but it is only recently that the consequences of persistent differences between individuals on population dynamics have been considered. In particular, few authors have addressed whether interactions exist between individual quality and environmental variation. In part, this is due to the difficulties of collecting sufficient data, but also the challenge of defining individual quality. Using a long-established study population of red deer, Cervus elaphus, inhabiting the North Block of the Isle of Rum, and three quality measures, this paper investigates how differences in maternal quality affect variation in birth body mass and date, as population density varies, and how this differs depending on the sex of the offspring and the maternal quality measure used. Significant interactions between maternal quality, measured as a hind's total contribution to population growth, and population density are reported for birth mass, but only for male calves. Analyses using dominance or age at primiparity to define maternal quality showed no significant interactions with population density, highlighting the difficulties of defining a consistent measure of individual quality. PMID:18522909
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Variations in the Availability of Pollen Resources Affect Honey Bee Health
Di Pasquale, Garance; Alaux, Cédric; Le Conte, Yves; Odoux, Jean-François; Pioz, Maryline; Vaissière, Bernard E.; Belzunces, Luc P.; Decourtye, Axel
2016-01-01
Intensive agricultural systems often expose honey bees (Apis mellifera L.) to large temporal variations in the availability (quantity, quality and diversity) of nutritional resources. Such nutritional irregularity is expected to affect honey bee health. We therefore tested under laboratory conditions the effect of such variation in pollen availability on honey bee health (survival and nursing physiology—hypopharyngeal gland development and vitellogenin expression). We fed honey bees with different diets composed of pollen pellets collected by honey bees in an agricultural landscape of western France. Slight drops (5–10%) in the availability of oilseed rape (Brassica napus L.) pollen resulted in significant reductions of all tested variables. Despite some variations in taxonomic diversity and nutritional quality, the pollen mixes harvested over the season had a similar positive influence on honey bee health, except for the one collected in late July that induced poor survival and nursing physiology. This period coincided with the mass-flowering of maize (Zea mays L.), an anemophilous crop which produces poor-quality pollen. Therefore, changes in bee health were not connected to variations in pollen diversity but rather to variations in pollen depletion and quality, such as can be encountered in an intensive agricultural system of western France. Finally, even though pollen can be available ad libitum during the mass-flowering of some crops (e.g. maize), it can fail to provide bees with diet adequate for their development. PMID:27631605
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Bitumoids in the crystalline rocks of the Kola superdeep drillhole
DOE Office of Scientific and Technical Information (OSTI.GOV)
Belokon, V.G.
1987-04-01
The genetic regularities in the distribution of organic fuels of various elemental compositions and molecular structures and their relationship to the processes of formation of regional structures present some of the most pressing and complicated problems of modern fossil-fuel geology. Regardless of the difference in molecular structure of the final products of these reactions and the phase state in nature (gases, petroleums, bitumens, lignite, bituminous coal or anthracite), fossil fuels manifest the property of carbon and hydrogen to yield a vast number of compounds with different extents of ordering of the structure, from simple linear compounds (methane and its homologs)more » to cyclic compounds of the graphite series. Karavayev worked out a classification diagram for solid fuels, based on calculation of the variation in the elemental composition of the organic matter. The ratio of hydrogen to carbon atoms, as a reflection of the extent of aromatization of the structure, is taken as a classification criterion. In investigating the earth's crust in the Baltic shield, the Kola superdeep drillhole found organic matter in the form of bitumoids, in the extractable part of which a broad spectrum of compounds was identified. Bitumoids are similar to humites in molecular structure, only somewhat more ordered. This paper applies Karavayev's principle to this type of compound. It was found that the elemental compositions of the organic matter from basement depths down to 10 km show patterns analogous to those from sedimentary basins. 9 references.« less
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Phenols as chemical fossils in coals. [Book chapter
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bimer, J.; Given, P.H.; Raj, S.
It is generally considered that vitrinite, the principal maceral in most coals, represents coalified, partly decayed wood. Hence lignin should be one of the important precursors to the vitrinites in coals. Accordingly, it would be interesting to know whether any chemical fossils related to lignin could be found in coals. The purpose of this paper is to report what we believe to be a successful search for such fossils. The experimental approach exploited a degradation reaction developed in a study of soil humic acids by Burges et al. This reaction involves a reductive degradation with sodium amalgam and hot water.more » Thin layer chromatography of the ether soluble part of the product (yield, about 20%) showed the presence of a number of phenols and phenolic acids, most of whose structures bore obvious relationships to known microbial and chemical degradation products of lignin but some to the A ring of flavonoids. Humic acids can be extracted from peats and lignites but not from bituminous coals. However, oxidation of bituminous coals with aqueous performic acid generates in high yield (80 to 110% by weight) materials that closely resemble humic acids. The Burges reductive degradation was applied to humic acids extracted from some peats and lignites, and produced by oxidation of a number of bituminous coals. A number of identifications of products were made originally by gas chromatography with co-injection of standards. In this preliminary publication the experimental procedures are described and a sufficient selection of the data are given to show what was found by co-injection and later confirmed by mass spectrometry.« less
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Kapusta, Krzysztof; Stańczyk, Krzysztof
2015-02-01
The effect of coal rank on the composition and toxicity of water effluents resulting from two underground coal gasification experiments with distinct coal samples (lignite and hard coal) was investigated. A broad range of organic and inorganic parameters was determined in the sampled condensates. The physicochemical tests were supplemented by toxicity bioassays based on the luminescent bacteria Vibrio fischeri as the test organism. The principal component analysis and Pearson correlation analysis were adopted to assist in the interpretation of the raw experimental data, and the multiple regression statistical method was subsequently employed to enable predictions of the toxicity based on the values of the selected parameters. Significant differences in the qualitative and quantitative description of the contamination profiles were identified for both types of coal under study. Independent of the coal rank, the most characteristic organic components of the studied condensates were phenols, naphthalene and benzene. In the inorganic array, ammonia, sulphates and selected heavy metals and metalloids were identified as the dominant constituents. Except for benzene with its alkyl homologues (BTEX), selected polycyclic aromatic hydrocarbons (PAHs), zinc and selenium, the values of the remaining parameters were considerably greater for the hard coal condensates. The studies revealed that all of the tested UCG condensates were extremely toxic to V. fischeri; however, the average toxicity level for the hard coal condensates was approximately 56% higher than that obtained for the lignite. The statistical analysis provided results supporting that the toxicity of the condensates was most positively correlated with the concentrations of free ammonia, phenols and certain heavy metals. Copyright © 2014 Elsevier Inc. All rights reserved.
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Adsorption of lignite-derived humic acids on coal-based mesoporous activated carbons.
Lorenc-Grabowska, Ewa; Gryglewicz, Grazyna
2005-04-15
The adsorption by a coal-based mesoporous activated carbon of humic acids (HAs) isolated from two Polish lignites was studied. For comparison, a commercial Aldrich humic acid was also included into this study. The differences in chemical structure and functional groups of HAs were determined by elemental analysis and infrared spectroscopy DRIFT. Two activated carbons used differed in terms of mesopore volume, mesopore size distribution, and chemical properties of the surface. The kinetics of adsorption of HAs have been discussed using three kinetic models, i.e., the first-order Lagergren model, the pseudo-second-order model, and the intraparticle diffusion model. It was found that the adsorption of HAs from alkaline solution on mesoporous activated carbon proceeds according to the pseudo-second-order model. The correlation coefficients were close to 1. The intraparticle diffusion of HA molecules within the carbon particle was identified to be the rate-limiting step. Comparing the two activated carbons, the carbon with a higher volume of pores with widths of 10-50 nm showed a greater removal efficiency of HA. An increase in the Freundlich adsorption capacity with decreasing carbon content of HA was observed. Among the HAs studied, S-HA shows characteristics indicating the highest contribution of small-size fraction. The S-HA was removed by both activated carbons to the highest extent. The effect of pH solution on the adsorption of HA was examined over the range pH 5.4-12.2. It was found that the extent of adsorption decreased with decreasing pH of the solution.
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NASA Astrophysics Data System (ADS)
Sarp, Gulcan; Duzgun, Sebnem
2015-11-01
A morphometric analysis of river network, basins and relief using geomorphic indices and geostatistical analyses of Digital Elevation Model (DEM) are useful tools for discussing the morphometric evolution of the basin area. In this study, three different indices including valley floor width to height ratio (Vf), stream gradient (SL), and stream sinuosity were applied to Afşin-Elbistan lignite basin to test the imprints of tectonic activity. Perturbations of these indices are usually indicative of differences in the resistance of outcropping lithological units to erosion and active faulting. To map the clusters of high and low indices values, the Kernel density estimation (K) and the Getis-Ord Gi∗ statistics were applied to the DEM-derived indices. The K method and Gi∗ statistic highlighting hot spots and cold spots of the SL index, the stream sinuosity and the Vf index values helped to identify the relative tectonic activity of the basin area. The results indicated that the estimation by the K and Gi∗ including three conceptualization of spatial relationships (CSR) for hot spots (percent volume contours 50 and 95 categorized as high and low respectively) yielded almost similar results in regions of high tectonic activity and low tectonic activity. According to the K and Getis-Ord Gi∗ statistics, the northern, northwestern and southern parts of the basin indicates a high tectonic activity. On the other hand, low elevation plain in the central part of the basin area shows a relatively low tectonic activity.
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Uptake of Cr3+ from aqueous solution by lignite-based humic acids.
Arslan, G; Pehlivan, E
2008-11-01
Humic acid (HA) produced from brown coal, a relatively abundant and inexpensive material is currently being investigated as an adsorbent to remove toxic metals from aqueous solution. The influence of five parameters (contact time, solution pH, initial metal concentration, temperature and amount of adsorbent) on the removal at 20+/-1 degrees C was studied. HAs were prepared from lignites by using alkaline extraction, sedimentation and acidic precipitation. Adsorption equilibrium was achieved in about 60 min for Cr3+ ion. The Langmuir adsorption isotherm was used to describe observed sorption phenomena. The maximum adsorption capacity of 0.17 mmol for Ilgin (HA1), 0.29 mmol for Beysehir (HA2) and 0.18 mmol Ermenek (HA3) and 0.17 mmol of Cr3+/g for activated carbon (AC) was achieved, respectively at pH of 4.1. More than 84% of Cr3+ was removed by HA2, 54% by HA3 and 51% by HA1 and 50% by AC from aqueous solution. The adsorption was strongly dependent on pH but independent of ionic strength and metal ions. The adsorption of Cr3+ was higher between pH 4.1 and 5.1 for all HAs and maximum sorption was observed at pH 4.1. The rise in temperature caused a slight decrease in the value of the equilibrium constant (Kc) for the sorption of Cr3+ ion. Complex mechanisms including ion exchange, complexation and adsorption and size exclusion are possible for sorption of Cr3+ ion on HAs.
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Effects of drilling fluids on soils and plants: I. Individual fluid components
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miller, R.W.; Honarvar, S.; Hunsaker, B.
1980-01-01
The effects of 31 drilling fluid (drilling mud) components on the growth of green beans (Phaseolus vulgaris L., Tendergreen) and sweet corn (Zea may var. saccharata (Sturtev.) Bailey, Northrup King 199) were evaluated in greenhouse studies. Plants grew well in fertile Dagor silt loam soil (Cumulic Haploxeroll) when the soil was mixed with most soil-component mixtures at disposal proportions normally expected. Vinyl acetate and maleic acid polymer (VAMA) addition caused significantly increased growth at the 95% confidence level. No statistically significant depression of plant growth occurred at normal rates with asbestos, asphalt, barite, bentonite, calcium lignosulfonate, sodium polyacrylate, a modifiedmore » tannin, ethoxylated nonylphenol, a filming amine, gilsonite, a Xanthan gum, paraformaldehyde, a pipe dope, hydrolized polyacrylamide, sodium acid pyrophosphate, sodium carboxymethyl cellulose, sodium hydroxide added as pellets, and a sulfonated tall oil. Statistically significant reductions in plant yields (at the 95% confidence level) occurred at normal disposal rates with a long-chained aliphatic alcohol, sodium dichromate, diesel oil, guar gum, an iron chromelignosulfonate, lignite, a modified asphalt, a plant fibersynthetic fiber mixture, lignite, a nonfermenting starch, potassium chloride, pregelatinized starch, and sulfated triglyceride. Thirteen drilling fluid components added individually to a fluid base (water, bentonite, and barite) and then to soil were also tested for their effect on plant growth. Only the sulfated triglyceride (Torq-Trim) and the long-chain (high molecular weight) alcohol (Drillaid 405) caused no plant growth reductions at either rate added. The modified tannin (Desco) caused minimal reduction in bean growth only when added to soil in excess levels.« less
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Activation of inoculum microorganism from dairy cattle feces
NASA Astrophysics Data System (ADS)
Ayuningtyas, Widya D.; Ridwan, Roni; Joni, I. M.; Marlina, E. T.; Harlia, Ellin
2018-02-01
Coal produces Coal Bed Methane (CBM) which is formed both biogenically and thermogenically. Lignite is not utilized optimally because it has low heat content and productivity time limit that decreases CBM production. In order to utilize lignite waste, adding inoculum consortium microorganism from dairy cattle waste as starter for biogas process can be a solution. This study aimed to produce inoculum consortium microorganism as biogas starter from dairy cattle feces through in vitro activation process by Theoudorou modification method. The research used complete randomized design with 3 replications. The treatments were blank (R0), 100% concentrate (R1), 70% concentrate+30% grass (R2), 70% grass+30% concentrate (R3) and 100% grass (R4). All treatments were added by buffer solution and feces with ratio of 2:1 into 100 ml serum injection bottle with anaerobic conditions. The parameters observed were gas production, pH and gas kinetics (orskov's equation) for 2, 4, 6, 8, 10, 12, 24 and 48 hours. The results showed that the treatment had significant effect (P <0.05) on the observed parameters. The highest total gas production was for R2 and R3 treatments with total production of 91.17 ml and 101.17 ml, pH (6.62 and 6.57), maximum gas production (94.03 and 97.62 ml), speed of gas production (0.066 and 0.084 ml/hour). There is not a significant difference for both the treatments. The source of inoculum consortium microorganisms for biogas starter selected based on the observed parameters and potential availability of proteolytic and fibrocytic microorganisms is R2 (70% concentrate +30% grass).
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Cronauer, D.C.; Swanson, A.J.; Sajkowski, D.J.
1992-12-31
Research in this project centered upon developing and evaluating catalysts and process improvements for coal liquefaction in the two-stage, close-coupled catalytic process. The major results are summarized here and they are described in more detail under each Task. In tasks for coal pretreatment and beneficiation, it was shown for coal handling that drying of both lignite or subbituminous coals using warm air, vacuum oven or exposing to air for long time was detrimental to subsequent liquefaction. Both laboratory and bench-scale beneficiations indicated that in order to achieve increased liquefaction yield for Illinois No. 6 bituminous coal, size separation with inmore » sink-float technique should be used. For subbituminous coal, the best beneficiation was aqueous SO{sub 2} treatment, which reduced mineral matter. In the case of lignite, the fines should be rejected prior to aqueous SO{sub 2} treatment and sink-float gravity separation. In liquefying coals with supported catalysts in both first and second stages, coal conversion was highest (93%) with Illinois No. 6 coal, which also had the highest total liquid yield of 80%, however, the product contained unacceptably high level of resid (30%). Both low rank coals gave lower conversion (85--87%) and liquid yields (57--59%), but lighter products (no resid). The analysis of spent first stage catalysts indicated significant sodium and calcium deposits causing severe deactivation. The second stage catalysts were in better condition showing high surface areas and low coke and metal deposits. The use of dispersed catalyst in the first stage would combat the severe deactivation.« less
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Visualizing the Quality of Vectur Features - a Proposal for Cadastral Maps
NASA Astrophysics Data System (ADS)
Navratil, G.; Leopoldseder, V.
2017-09-01
A well-known problem of geographical information is the communication of the quality level. It can be either done verbally / numerically or it can be done graphically. The graphical form is especially useful if the quality has a spatial variation because the spatial distribution is visualized as well. The problem of spatial variation of quality is an issue for cadastral maps. Non-experts cannot determine the quality at a specific location. Therefore a visual representation was tested for the Austrian cadastre. A map sheet was redesigned to give some indication of cadastral quality and presented to both experts and non-experts. The paper presents the result of the interviews.
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The Quality of the Head Start Planned Variation Data. Volume I.
ERIC Educational Resources Information Center
Walker, Debbie Klein; And Others
This publication, the first of two volumes, describes the cognitive, psychomotor, and socioemotional measures used in all years of the Head Start Planned Variation Evaluation. Part I discusses generally the issues involved in evaluating the quality of the data, and summarizes findings. Part II contains technical reports on 12 of the individual…
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USDA-ARS?s Scientific Manuscript database
This research was performed to determine variation of protein molecular weight distribution (MWD) parameters using size exclusion HPLC and their associations with quality characteristics and free asparagine concentration (FAC) using eleven hard red spring (HRS) wheat genotypes grown at three locatio...
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Li, Manjie; Liu, Zhaowei; Chen, Yongcan; Hai, Yang
2016-12-01
Interaction between old, corroded iron pipe surfaces and bulk water is crucial to the water quality protection in drinking water distribution systems (WDS). Iron released from corrosion products will deteriorate water quality and lead to red water. This study attempted to understand the effects of pipe materials on corrosion scale characteristics and water quality variations in WDS. A more than 20-year-old hybrid pipe section assembled of unlined cast iron pipe (UCIP) and galvanized iron pipe (GIP) was selected to investigate physico-chemical characteristics of corrosion scales and their effects on water quality variations. Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Inductively Coupled Plasma (ICP) and X-ray Diffraction (XRD) were used to analyze micromorphology and chemical composition of corrosion scales. In bench testing, water quality parameters, such as pH, dissolved oxygen (DO), oxidation reduction potential (ORP), alkalinity, conductivity, turbidity, color, Fe 2+ , Fe 3+ and Zn 2+ , were determined. Scale analysis and bench-scale testing results demonstrated a significant effect of pipe materials on scale characteristics and thereby water quality variations in WDS. Characteristics of corrosion scales sampled from different pipe segments show obvious differences, both in physical and chemical aspects. Corrosion scales were found highly amorphous. Thanks to the protection of zinc coatings, GIP system was identified as the best water quality stability, in spite of high zinc release potential. It is deduced that the complicated composition of corrosion scales and structural break by the weld result in the diminished water quality stability in HP system. Measurement results showed that iron is released mainly in ferric particulate form. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Alonso, Conchita; Navarro-Fernández, Carmen M; Arceo-Gómez, Gerardo; Meindl, George A; Parra-Tabla, Víctor; Ashman, Tia-Lynn
2013-11-01
Insufficient pollination is a function of quantity and quality of pollen receipt, and the relative contribution of each to pollen limitation may vary with intrinsic plant traits and extrinsic ecological properties. Community-level studies are essential to evaluate variation across species in quality limitation under common ecological conditions. This study examined whether endemic species are more limited by pollen quantity or quality than non-endemic co-flowering species in three endemic-rich plant communities located in biodiversity hotspots of different continents (Andalusia, California and Yucatan). Natural variations in pollen receipt and pollen tube formation were analysed for 20 insect-pollinated plants. Endemic and non-endemic species that co-flowered were paired in order to estimate and compare the quantity and quality components of pre-zygotic pollination success, obtained through piecewise regression analysis of the relationship between pollen grains and pollen tubes of naturally pollinated wilted flowers. Pollen tubes did not frequently exceed the number of ovules per flower. Only the combination of abundant and good quality pollen and a low number of ovules per flower conferred relief from pre-zygotic pollen limitation in the three stochastic pollination environments studied. Quality of pollen receipt was found to be as variable as quantity among study species. The relative pollination success of endemic and non-endemic species, and its quantity and quality components, was community dependent. Assessing both quality and quantity of pollen receipt is key to determining the ovule fertilization potential of both endemic and widespread plants in biodiverse hotspot regions. Large natural variation among flowers of the same species in the two components and pollen tube formation deserves further analysis in order to estimate the environmental, phenotypic and intraindividual sources of variation that may affect how plants evolve to overcome this limitation in different communities worldwide.
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Animal breeding strategies can improve meat quality attributes within entire populations.
Berry, D P; Conroy, S; Pabiou, T; Cromie, A R
2017-10-01
The contribution of animal breeding to changes in animal performance is well documented across a range of species. Once genetic variation in a trait exists, then breeding to improve the characteristics of that trait is possible, if so desired. Considerable genetic variation exists in a range of meat quality attributes across a range of species. The genetic variation that exists for meat quality is as large as observed for most performance traits; thus, within a well-structured breeding program, rapid genetic gain for meat quality could be possible. The rate of genetic gain can be augmented through the integration of DNA-based technologies into the breeding program; such DNA-based technologies should, however, be based on thousands of DNA markers dispersed across the entire genome. Genetic and genomic technologies can also have beneficial impact outside the farm gate as a tool to segregate carcasses or meat cuts based on expected meat quality features. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Quality improvement in neonatal care - a new paradigm for developing countries.
Chawla, Deepak; Suresh, Gautham K
2014-12-01
Infrastructure for facility-based neonatal care has rapidly grown in India over last few years. Experience from developed countries indicates that different health facilities have varying clinical outcomes despite accounting for differences in illness severity of admitted neonates and random variation. Variation in quality of care provided at different neonatal units may account for variable clinical outcomes. Monitoring quality of care, comparing outcomes across different centers and conducting collaborative quality improvement projects can improve outcome of neonates in health facilities. Top priority should be given to establishing quality monitoring and improvement procedures at special care neonatal units and neonatal intensive care units of the country. This article presents an overview of methods of quality improvement. Literature reports of successful collaborative quality improvement projects in neonatal health are also reviewed.
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NASA Astrophysics Data System (ADS)
Jenerette, D.; Wang, J.; Chandler, M.; Ripplinger, J.; Koutzoukis, S.; Ge, C.; Castro Garcia, L.; Kucera, D.; Liu, X.
2017-12-01
Large uncertainties remain in identifying the distribution of urban air quality and temperature risks across neighborhood to regional scales. Nevertheless, many cities are actively expanding vegetation with an expectation to moderate both climate and air quality risks. We address these uncertainties through an integrated analysis of satellite data, atmospheric modeling, and in-situ environmental sensor networks maintained by citizen scientists. During the summer of 2017 we deployed neighborhood-scale networks of air temperature and ozone sensors through three campaigns across urbanized southern California. During each five-week campaign we deployed six sensor nodes that included an EPA federal equivalent method ozone sensor and a suite of meteorological sensors. Each node was further embedded in a network of 100 air temperature sensors that combined a randomized design developed by the research team and a design co-created by citizen scientists. Between 20 and 60 citizen scientists were recruited for each campaign, with local partners supporting outreach and training to ensure consistent deployment and data gathering. We observed substantial variation in both temperature and ozone concentrations at scales less than 4km, whole city, and the broader southern California region. At the whole city scale the average spatial variation with our ozone sensor network just for city of Long Beach was 26% of the mean, while corresponding variation in air temperature was only 7% of the mean. These findings contrast with atmospheric model estimates of variation at the regional scale of 11% and 1%. Our results show the magnitude of fine-scale variation underestimated by current models and may also suggest scaling functions that can connect neighborhood and regional variation in both ozone and temperature risks in southern California. By engaging citizen science with high quality sensors, satellite data, and real-time forecasting, our results help identify magnitudes of climate and air quality risk variation across scales and can guide individual decisions and urban policies surrounding vegetation to moderate these risks.
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Bayesian denoising in digital radiography: a comparison in the dental field.
Frosio, I; Olivieri, C; Lucchese, M; Borghese, N A; Boccacci, P
2013-01-01
We compared two Bayesian denoising algorithms for digital radiographs, based on Total Variation regularization and wavelet decomposition. The comparison was performed on simulated radiographs with different photon counts and frequency content and on real dental radiographs. Four different quality indices were considered to quantify the quality of the filtered radiographs. The experimental results suggested that Total Variation is more suited to preserve fine anatomical details, whereas wavelets produce images of higher quality at global scale; they also highlighted the need for more reliable image quality indices. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Correction of stream quality trends for the effects of laboratory measurement bias
Alexander, Richard B.; Smith, Richard A.; Schwarz, Gregory E.
1993-01-01
We present a statistical model relating measurements of water quality to associated errors in laboratory methods. Estimation of the model allows us to correct trends in water quality for long-term and short-term variations in laboratory measurement errors. An illustration of the bias correction method for a large national set of stream water quality and quality assurance data shows that reductions in the bias of estimates of water quality trend slopes are achieved at the expense of increases in the variance of these estimates. Slight improvements occur in the precision of estimates of trend in bias by using correlative information on bias and water quality to estimate random variations in measurement bias. The results of this investigation stress the need for reliable, long-term quality assurance data and efficient statistical methods to assess the effects of measurement errors on the detection of water quality trends.