WorldWideScience

Sample records for depolymerize lignite coals

  1. Enzymatic depolymerization of low-rank coal (lignite)

    Energy Technology Data Exchange (ETDEWEB)

    Hofrichter, M.; Ziegenhagen, D.; Sorge, S.; Bublitz, F.; Fritsche, W. [Jena Univ. (Germany). Inst. fuer Mikrobiologie

    1997-12-31

    Ligninolytic basidiomycetes (wood and litter decaying fungi) have the ability to degrade low-rank coal (lignite). Extracellular manganese peroxidase (MnP) is the decisive enzyme in the depolymerization process both of coal derived humic substances and native coal. The depolymerization of coal occurred via Mn{sup 3+}-ions acting as primary mediator and can be considerably enhanced by certain thiols acting as secondary mediators. The depolymerization process leads finally to complex mixtures of fulvic acid-like compounds. (orig.)

  2. Bioprocessing of lignite coals using reductive microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, D.L.

    1992-03-29

    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 coal depolymerizing enzymes.

  3. (Bioprocessing of lignite coals using reductive microorganisms)

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, D.L.

    1990-01-01

    The objectives of this report are to: (1) characterize selected aerobic bacterial strains for their abilities to depolymerize lignite coal polymers, and isolate and identify the extracellular enzymes responsible for depolymerization of the coal; (2) characterize selected strictly anaerobic bacteria, that were previously shown to reductively transform coal substructure model compounds, for the ability to similarly transform polymeric coal; and (3) isolate more strains of anaerobic bacteria by enrichment using additional coal substructure model compounds and coal as substrates.

  4. Bioprocessing of lignite coals using reductive microorganisms. Final technical report, September 30, 1988--March 29, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, D.L.

    1992-03-29

    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 coal depolymerizing enzymes.

  5. COFIRING BIOMASS WITH LIGNITE COAL

    Energy Technology Data Exchange (ETDEWEB)

    Darren D. Schmidt

    2002-01-01

    The University of North Dakota Energy & Environmental Research Center, in support of the U.S. Department of Energy's (DOE) biomass cofiring program, completed a Phase 1 feasibility study investigating aspects of cofiring lignite coal with biomass relative to utility-scale systems, specifically focusing on a small stoker system located at the North Dakota State Penitentiary (NDSP) in Bismarck, North Dakota. A complete biomass resource assessment was completed, the stoker was redesigned to accept biomass, fuel characterization and fireside modeling tests were performed, and an engineering economic analysis was completed. In general, municipal wood residue was found to be the most viable fuel choice, and the modeling showed that fireside problems would be minimal. Experimental ash deposits from firing 50% biomass were found to be weaker and more friable compared to baseline lignite coal. Experimental sulfur and NO{sub x} emissions were reduced by up to 46%. The direct costs savings to NDSP, from cogeneration and fuel saving, results in a 15- to 20-year payback on a $1,680,000 investment, while the total benefits to the greater community would include reduced landfill burden, alleviation of fees for disposal by local businesses, and additional jobs created both for the stoker system as well as from the savings spread throughout the community.

  6. NAFTA opportunities: Bituminous coal and lignite mining

    Energy Technology Data Exchange (ETDEWEB)

    1993-01-01

    The North American Free Trade Agreement (NAFTA) secures and improves market access in Mexico and Canada for the United States bituminous coal and lignite mining sector. Canada is one of the United States' largest export markets for bituminous coal and lignite, with exports of $486.7 million in 1992. Conversely, the Mexican market is one of the smallest export markets for U.S. producers with exports of $1.8 million in 1992. Together, however, Canada and Mexico represent approximately 15 percent of total U.S. coal exports. The report presents a sectoral analysis.

  7. Planning for reliable coal quality delivery considering geological variability: A case study in polish lignite mining

    NARCIS (Netherlands)

    Naworyta, W.; Sypniowski, S.; Benndorf, J.

    2015-01-01

    The aim of coal quality control in coal mines is to supply power plants daily with extracted raw material within certain coal quality constraints. On the example of a selected part of a lignite deposit, the problem of quality control for the runof-mine lignite stream is discussed. The main goal is t

  8. Planning for reliable coal quality delivery considering geological variability: A case study in polish lignite mining

    NARCIS (Netherlands)

    Naworyta, W.; Sypniowski, S.; Benndorf, J.

    2015-01-01

    The aim of coal quality control in coal mines is to supply power plants daily with extracted raw material within certain coal quality constraints. On the example of a selected part of a lignite deposit, the problem of quality control for the runof-mine lignite stream is discussed. The main goal is

  9. The hydrogasification of lignite and sub-bituminous coals

    Science.gov (United States)

    Bhatt, B.; Fallon, P. T.; Steinberg, M.

    1981-02-01

    A North Dakota lignite and a New Mexico sub-bituminous coal have been hydrogenated at up to 900°C and 2500 psi hydrogen pressure. Yields of gaseous hydrocarbons and aromatic liquids have been studied as a function of temperature, pressure, residence time, feed rates and H2/coal ratio. Coal feed rates in excess of 10 lb/hr have been achieved in the 1 in. I. D.×8 ft reactor and methane concentration as high as 55% have been observed. A four-step reaction model was developed for the production and decomposition of the hydrocarbon products. A single object function formulated from the weighted errors for the four dependent process, variables, CH4, C2H6, BTX, and oil yields, was minimized using a program containing three independent iterative techniques. The results of the nonlinear regression analysis for lignite show that a first-order chemical reaction model with respect to C conversion satisfactorily describes the dilute phase hydrogenation. The activation energy for the initial products formation was estimated to be 42,700 cal/gmole and the power of hydrogen partial pressure was found to be +0.14. The overall correlation coefficient was 0.83. The mechanism, the rate expressions, and the design curves developed can be used for scale-up and reactor design.

  10. Kinetic Study and Thermal Decomposition Behavior of Lignite Coal

    Directory of Open Access Journals (Sweden)

    Mehran Heydari

    2015-01-01

    Full Text Available A thermogravimetric analyzer was employed to investigate the thermal behavior and extract the kinetic parameters of Canadian lignite coal. The pyrolysis experiments were conducted in temperatures ranging from 298 K to 1173 K under inert atmosphere utilizing six different heating rates of 1, 6, 9, 12, 15, and 18 K min−1, respectively. There are different techniques for analyzing the kinetics of solid-state reactions that can generally be classified into two categories: model-fitting and model-free methods. Historically, model-fitting methods are broadly used in solid-state kinetics and show an excellent fit to the experimental data but produce uncertain kinetic parameters especially for nonisothermal conditions. In this work, different model-free techniques such as the Kissinger method and the isoconversional methods of Ozawa, Kissinger-Akahira-Sunose, and Friedman are employed and compared in order to analyze nonisothermal kinetic data and investigate thermal behavior of a lignite coal. Experimental results showed that the activation energy values obtained by the isoconversional methods were in good agreement, but Friedman method was considered to be the best among the model-free methods to evaluate kinetic parameters for solid-state reactions. These results can provide useful information to predict kinetic model of coal pyrolysis and optimization of the process conditions.

  11. Experimental Study of Hydrogasification of Lignite and Subbituminous Coal Chars

    Directory of Open Access Journals (Sweden)

    Stanisław Gil

    2015-01-01

    Full Text Available 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 dmn3/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.

  12. Combustion of producer gas from gasification of south Sumatera lignite coal using CFD simulation

    National Research Council Canada - National Science Library

    Fajri Vidian; Novia; Andy Suryatra

    2017-01-01

    .... The process was carried out using producer gas from lignite coal gasification of BA 59 was produced by the updraft gasifier which is located on Energy Conversion Laboratory Mechanical Engineering...

  13. REMOVAL OF TRICHLOROACETIC ACID FROM THE AQUEOUS SOLUTIONS USING NATURAL AND ACTIVATED LIGNITE COALS

    Directory of Open Access Journals (Sweden)

    Hüseyin GÜLENSOY

    1998-02-01

    Full Text Available In these studies, a typical lignite coal found near Istanbul (Yeniköy and its activated products were used to adsorb TCA from aqueous solutions. Particle sizes of coal samples and the concentrations of TCA solutions were chosen as parameters against the fixed amount of adsorbent. The maximum efficiency has been obtained for the coal having (-120 + 150 mesh size fraction activated by heating. As a result, it was shown that these kinds of lignite coals could be used as a good adsorbent. In addition, it was also proved that both the removal and recovery of TCA from some waste waters would easily be possible.

  14. Depolymerization of coal by oxidation and alkylation; Sanka bunkai to alkyl ka ni yoru sekitan kaijugo

    Energy Technology Data Exchange (ETDEWEB)

    Tomita, H.; Isoda, T.; Kusakabe, K.; Morooka, S. [Kyushu University, Fukuoka (Japan). Faculty of Engineering; Hayashi, J. [Hokkaido University, Sapporo (Japan). Center for Advanced Research of Energy Technology

    1996-10-28

    Change in depolymerization degree and coal structure was studied for depolymerization treatment of coal in various alcohol containing aqueous hydrogen peroxide. In experiment, the mixture of Yallourn coal, alcohol and aqueous hydrogen peroxide was agitated in nitrogen atmosphere of normal pressure at 70{degree}C for 12 hours. As the experimental result, the methanol solubility of only 5% of raw coal increased up to 35.2% by hydrogen peroxide treatment, while the yield of insoluble matters also decreased from 94% to 62%. Most of the gas produced during treatment was composed of inorganic gases such as CO and CO2, and its carbon loss was extremely decreased by adding alcohol. From the analytical result of carbon loss in hydrogen peroxide treatment, it was clarified that alkylation advances with introduction of alkyl group derived from alcohol into coal by hydrogen peroxide treatment under a coexistence of alcohol, and depolymerization reaction of coal itself is thus promoted by alcohol. 4 refs., 7 figs., 1 tab.

  15. Mineralogy and microstructure of sintered lignite coal fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Marina Ilic; Christopher Cheeseman; Christopher Sollars; Jonathan Knight [Faculty of Technology and Metallurgy, Belgrade (Yugoslavia)

    2003-02-01

    Lignite coal fly ash from the 'Nikola Tesla' power plant in Yugoslavia has been characterised, milled, compacted and sintered to form monolithic ceramic materials. The effect of firing at temperatures between 1130 and 1190{sup o}C on the density, water accessible porosity, mineralogy and microstructure of sintered samples is reported. This class C fly ash has an initial average particle size of 82 {mu}m and contains siliceous glass together with the crystalline phases quartz, anorthite, gehlenite, hematite and mullite. Milling the ash to an average particle size of 5.6 m, compacting and firing at 1170{sup o}C for 1 h produces materials with densities similar to clay-based ceramics that exhibit low water absorption. Sintering reduces the amount of glass, quartz, gehlenite and anhydrite, but increases formation of anorthite, mullite, hematite and cristobalite. SEM confirms the formation of a dense ceramic at 1170{sup o}C and indicates that pyroplastic effects cause pore formation and bloating at 1190{sup o}C. 23 refs., 6 figs., 2 tabs.

  16. Research on the thermal decomposition of Mongolian Baganuur lignite and Naryn sukhait bituminous coal

    Directory of Open Access Journals (Sweden)

    A. Ariunaa

    2016-03-01

    Full Text Available The technical characteristics, elemental composition of the organic and mineral matters, ash melting behaviors and carbonization and gasification reactivities of coals from Baganuur and Naryn sukhait deposits were investigated. The results of proximate and ultimate analysis confirmed that the coal from Baganuur deposit can be graded as a low rank lignite B2 mark coal and Naryn sukhait coal is a bituminous G mark one. The carbonization and gasification experiments were performed using TGA apparatus and fixed bed quartz reactor. The data obtained with two experimental reactors showed that Baganuur lignite had lower thermal stability and much higher CO2 gasification reactivity at 950°C as compared to those for Naryn sukhait bituminous coal.Mongolian Journal of Chemistry 16 (42, 2015, 22-29

  17. Acid leaching of coal: to produce clean fuels from Turkish lignite

    Energy Technology Data Exchange (ETDEWEB)

    Seferinoglu, Meryem [Mineral Research and Exploration Directorate (Turkey)], email: meryem_seferinoglu66@yahoo.com; Duzenli, Derya [Ankara Central Laboratory (Turkey)

    2011-07-01

    With the increasing concerns about the environment, energy producers and governments are looking at developing clean energy sources. However, Turkey has limited clean energy resources and is using low grade coal which has high sulphur content as an alternative energy source. The aim of this paper is to study the possibility of generating clean fuel from Edirne Lignite and to get a better understanding of chemical mechanisms involved in coal leaching with hydrofluoric acid (HF) solutions. Leaching was conducted on Edirne Lignite with HF solution at ambient temperature and the effects of parameters such as reaction time and concentration of acid solutions on the process were evaluated. The optimum conditions were found and it was shown that ash levels can be reduced from 28.9% to 10.5% and the calorific value increased by 500kcal/kg with the HF leaching method. This study demonstrated that the production of clean fuel from high sulphur lignite is possible.

  18. Purification, characterization, and coal depolymerizing activity of lignin peroxidase from Gloeophyllum sepiarium MTCC-1170

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, M.; Yadav, P.; Yadav, K.D.S. [DDU Gorakhpur University, Gorakhpur (India). Dept. of Chemistry

    2009-10-15

    Lignin peroxidase from the liquid culture filtrate of Gloeophyllum sepiarium MTCC-1170 has been purified to homogeneity. The molecular weight of the purified enzyme was 42 kDa as determined by SDS-PAGE. The K{sub m} values were 54 and 76 {mu}M for veratryl alcohol and H{sub 2}O{sub 2}, respectively. The pH and temperature optima were 2.5 and 25{sup o}C, respectively. Depolymerization of coal by the fungal strain has been demonstrated using humic acid as a model of coal. Depolymerization of humic acid by the purified lignin peroxidase has been shown by the decrease in absorbance at 450 nm and increase in absorbance at 360 nm in presence of H{sub 2}O{sub 2}. Depolymerization of humic acid by the purified enzyme has also been demonstrated by the decrease in the viscosity with time of the reaction solution containing humic acid, H{sub 2}O{sub 2}, and the purified lignin peroxidase. The influence of NaCl and NaN{sub 3} and inhibitory effects of various metal chelating agents on the lignin peroxidase activity were studied.

  19. A comparative study on the recovery of polycyclic aromatic hydrocarbons from fly ash and lignite coal.

    Science.gov (United States)

    Arditsoglou, Anastasia; Terzi, Eleni; Kalaitzoglou, Maria; Samara, Constantini

    2003-01-01

    The recovery of polycyclic aromatic hydrocarbons (PAHs) from lignite coal burnt in Greek power stations and the fly ash produced is examined comparatively using Soxhlet, ultrasonic and accelerated solvent extraction procedures with various organic solvents. Soxhlet using toluene/methanol mixture and accelerated solvent extraction/toluene were found to be the most efficient methods for fly ash PAHs, yielding average recoveries of about 80%. The accelerated solvent extraction/toluene procedure was superior for lignite PAHs, yielding 96% average recovery, whereas ultrasonic and Soxhlet extraction yielded relatively lower recoveries (75% and 67%, respectively).

  20. Planning for Reliable Coal Quality Delivery Considering Geological Variability: A Case Study in Polish Lignite Mining

    Directory of Open Access Journals (Sweden)

    Wojciech Naworyta

    2015-01-01

    Full Text Available The aim of coal quality control in coal mines is to supply power plants daily with extracted raw material within certain coal quality constraints. On the example of a selected part of a lignite deposit, the problem of quality control for the run-of-mine lignite stream is discussed. The main goal is to understand potential fluctuations and deviations from production targets dependent on design options before an investment is done. A single quality parameter of the deposit is selected for this analysis—the calorific value of raw lignite. The approach requires an integrated analysis of deposit inherent variability, the extraction sequence, and the blending option during material transportation. Based on drill-hole data models capturing of spatial variability of the attribute of consideration are generated. An analysis based on two modelling approaches, Kriging and sequential Gaussian simulation, reveals advantages and disadvantages lead to conclusions about their suitability for the control of raw material quality. In a second step, based on a production schedule, the variability of the calorific value in the lignite stream has been analysed. In a third step the effect of different design options, multiple excavators and a blending bed, was investigated.

  1. Combustion of producer gas from gasification of south Sumatera lignite coal using CFD simulation

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    Vidian Fajri

    2017-01-01

    Full Text Available The production of gasses from lignite coal gasification is one of alternative fuel for the boiler or gas turbine. The prediction of temperature distribution inside the burner is important for the application and optimization of the producer gas. This research aims to provide the information about the influence of excess air on the temperature distribution and combustion product in the non-premixed burner. The process was carried out using producer gas from lignite coal gasification of BA 59 was produced by the updraft gasifier which is located on Energy Conversion Laboratory Mechanical Engineering Department Universitas Sriwijaya. The excess air used in the combustion process were respectively 10%, 30% and 50%. CFD Simulations was performed in this work using two-dimensional model of the burner. The result of the simulation showed an increase of excess air, a reduction in the gas burner temperature and the composition of gas (carbon dioxide, nitric oxide and water vapor.

  2. THE COMPARISION OF SOMA LIGNITE COAL AN FUEL-OIL WITH GEOTHERMAL ENERGY FOR HEATING BUILDINGS

    OpenAIRE

    GÜNTÜRKÜN, Rüstü

    2008-01-01

    In this study, a house that has four storeys and one hundred square meters flat was taken sample. Because this house can be heated with three different alternatives Soma lignite coal, fuel oil and geothermal, necessary first investment and annual heating costs were investigated. In addition, at heating building of geothermal energy whether became economic was researched. Economic analysis of used fuels at heating to a flat that is one hundred square meters been done. According to result of...

  3. Annotated bibliography of coal in the Caribbean region. [Lignite

    Energy Technology Data Exchange (ETDEWEB)

    Orndorff, R.C.

    1985-01-01

    The purpose of preparing this annotated bibliography was to compile information on coal localities for the Caribbean region used for preparation of a coal map of the region. Also, it serves as a brief reference list of publications for future coal studies in the Caribbean region. It is in no way an exhaustive study or complete listing of coal literature for the Caribbean. All the material was gathered from published literature with the exception of information from Cuba which was supplied from a study by Gordon Wood of the US Geological Survey, Branch of Coal Resources. Following the classification system of the US Geological Survey (Wood and others, 1983), the term coal resources has been used in this report for reference to general estimates of coal quantities even though authors of the material being annotated may have used the term coal reserves in a similar denotation. The literature ranges from 1857 to 1981. The countries listed include Colombia, Mexico, Venezuela, Cuba, the Dominican Republic, Haiti, Jamaica, Puerto Rico, and the countries of Central America.

  4. Fixed-bed gasification research using US coals. Volume 10. Gasification of Benton lignite

    Energy Technology Data Exchange (ETDEWEB)

    Thimsen, D.; Maurer, R.E.; Pooler, A.R.; Pui, D.; Liu, B.; Kittelson, D.

    1985-05-01

    A single-staged, fixed-bed Wellman-Galusha gasifier coupled with a hot, raw gas combustion system and scrubber has been used to gasify numerous coals from throughout the United States. The gasification test program is organized as a cooperative effort by private industrial participants and governmental agencies. The consortium of participants is organized under the Mining and Industrial Fuel Gas (MIFGa) Group. This report is the tenth volume in a series of reports describing the atmospheric pressure, fixed-bed gasification of US coals. This specific report describes the gasification of Benton lignite. The period of gasification test was November 1-8, 1983. 16 refs., 22 figs., 19 tabs.

  5. Preparation of low-ash products from Slovak lignitic coals – material balance

    Directory of Open Access Journals (Sweden)

    Anton Zubrík

    2006-12-01

    Full Text Available A preparation of low-ash coal products was performed with the aim to obtain asuitable charge for the extraction following processes of organic substances. Thus, for this purpose, the coal feeds from two collieries, namely Záhorie and Nováky were washed in the water-only cyclone with a diameter of 150 mm. The vortex finder and apex diameters were 68 mm and 14.6 mm, respectively. The cone consisting of three angle sections 135°-75°-20° was applied. The products obtained on the overflow of the cyclone were decantated to remove the rests of slurries. In such a way, washed coals with the ash content in the dry matter of 5.44 was prepared from lignite of Záhorie. Similarly, as to coal from Nováky the ash content of 9.21 % was achieved.

  6. Biodepolymerization studies of low rank Indian coals

    Energy Technology Data Exchange (ETDEWEB)

    Selvi, V.A.; Banerjee, R.; Ram, L.C.; Singh, G. [FRI, Dhanbad (India). Environmental Management Division

    2009-10-15

    Biodepolymerization of some of the lower rank Indian coals by Pleurotus djamor, Pleurotus citrinopileatus and Aspergillus species were studied in a batch system. The main disadvantage in burning low rank coals is the low calorific values. To get the maximum benefit from the low rank coals, the non fuel uses of coals needs to be explored. The liquefaction of coals is the preliminary processes for such approaches. The present study is undertaken specifically to investigate the optimization of bio depolymerization of Neyveli lignite by P. djmor. The pH of the media reached a constant value of about 7.8 by microbial action. The effect of different carbon and nitrogen sources and influence of chelators and metal ions on depolymerization of lignite were also studied. Lignite was solubilized by P. djamor only to a limited extent without the addition of carbon and nitrogen sources. Sucrose was the best suitable carbon source for coal depolymerization by P. djamor and sodium nitrate followed by urea was the best nitrogen source. The Chelators like salicylic acid, TEA and metal ions Mg{sup 2+}, Fe{sup 3+}, Ca{sup 2+}, Cu{sup 2+}, Mn{sup 2+} has enhanced the lignite solubilization process. The finding of the study showed that, compared to sub-bituminous and bituminous coal, the lignite has higher rate of solubilization activity.

  7. Structural insights from boron tribromide ether cleavage into lignites and low maturity coals from the New Zealand Coal Band

    DEFF Research Database (Denmark)

    Glombitza, Clemens; Mangelsdorf, Kai; Horsfield, Brian

    2011-01-01

    structure, boron tribromide (BBr3) ether cleavage was applied to a series of lignite and coal samples of different maturity (R0 0.27–0.80%) obtained from coal mines and natural outcrops from the North and South Island of New Zealand. Terminal ether-bound alcohols rapidly decrease during diagenesis and occur...... only in low amounts during the catagenetic stage. Comparison between ester- and ether-bound terminal alcohols indicates a parallel decreasing trend during the diagenetic stage, suggesting that the stability differences between both linkages are not large enough to be observed in maturation processes...... over geological time scales. Polyether compounds were detected with chain length up to five carbon atoms. After a small decrease during the diagenetic phase these compounds occur in relatively high concentrations, even in the main catagenetic stage. This suggests that these linkage structures represent...

  8. Uncertainty estimation by Bayesian approach in thermochemical conversion of walnut hull and lignite coal blends.

    Science.gov (United States)

    Buyukada, Musa

    2017-05-01

    The main purpose of the present study was to incorporate the uncertainties in the thermal behavior of walnut hull (WH), lignite coal, and their various blends using Bayesian approach. First of all, thermal behavior of related materials were investigated under different temperatures, blend ratios, and heating rates. Results of ultimate and proximate analyses showed the main steps of oxidation mechanism of (co-)combustion process. Thermal degradation started with the (hemi-)cellulosic compounds and finished with lignin. Finally, a partial sensitivity analysis based on Bayesian approach (Markov Chain Monte Carlo simulations) were applied to data driven regression model (the best fit). The main purpose of uncertainty analysis was to point out the importance of operating conditions (explanatory variables). The other important aspect of the present work was the first performance evaluation study on various uncertainty estimation techniques in (co-)combustion literature.

  9. Emission characteristics of co-combustion of sewage sludge with olive cake and lignite coal in a circulating fluidized bed.

    Science.gov (United States)

    Toraman, Oner Yusuf; Topal, Hüseyin; Bayat, Oktay; Atimtay, Aysel T

    2004-01-01

    In this study, a circulating fluidized bed (CFB) of 125 mm diameter and 1800mm height was used to find the combustion characteristics of sewage sludge (SS) produced in Turkey. Sludge + olive cake, and sludge + lignite coal mixtures were burned separately. Various sludge-to-lignite coal and sludge-to-olive cake ratios (5/95, 10/90, 15/85, 20/80) were tried. On-line concentrations of major components (O2, SO2, CO2, CO, NOx, CmHn) were measured in the flue gas, as well as temperature and pressure distributions along the bed. Combustion efficiencies of sludge + olive cake and sludge + lignite coal mixtures were calculated, and the optimum conditions for operating parameters were discussed. The results have shown that the combustion mainly takes place in the upper regions of the main column where the temperature reaches 900 degrees C. SS + Coal burn in the CFB with an efficiency of 95.14% to 96.18%, which is considered to be quite good. When burning sludge mixed with olive cake, appreciable amounts of CO and unburned hydrocarbons are formed and the combustion efficiency drops to 92.93%. CO and CmHn emissions are lower when lignite coal is mixed with various amounts of SS than the emissions when the coal is burned alone. As the %SS is increased in the fuel mixture, the SO2 emission decreases. NOx emissions are slightly higher. When burning sludge mixed with olive cake, SO2 and NOx emissions are slightly higher. CO and CmHn emissions decrease sharply when SS is mixed with 5%wt. olive cake. With increasing sludge ratio these emissions increase due to the unburned hydrocarbons. As a result of this study, it is believed that SS can be burned effectively in a CFBC together with other fuels, especially with olive cake (OC). OC will be a good additive fuel for the combustion of lower quality fuels.

  10. Kinetics and mechanisms of hydroliquefaction and hydrogasification of lignite. [Cellulose, wood, manure, municipal waste, coal of various ranks, fuel oil and natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, A.H.; Kranich, W.L.; Geureuz, K.

    1981-01-01

    A high pressure, continuous, stirred-tank reactor system has been constructed for the study of the catalytic liquefaction of North Dakota lignite slurried in anthracene oil. The conversion of lignite using a cobalt-molybdenum on alumina catalyst and the distribution of products as preasphaltenes, asphaltenes, oils and gases has been studied at the following conditions: temperature, 375 to 440/sup 0/C; pressure, 1000 to 1600 psig; agitator speed, 800 to 1500 rpm; catalyst concentration, 0 to 10% (based on lignite); initial lignite concentration, 5 to 30%; and space time, 16 to 52 minutes. At reactor pressures above 1500 psig and agitator speeds above 1000 rpm, reaction rate was essentially independent of pressure. At catalyst concentrations above 1% (based on lignite), the conversion of lignite was essentially independent of catalyst concentration. Experiments were conducted above these limits to find the effect on lignite conversion rate, of initial lignite concentration, and space time, or degree of conversion. The results at constant temperature were correlated by an equation which is given in the report. The relationship between the rate constant, K, and temperature, and between the maximum conversion and temperature was established. The effect of reaction conditions on the distribution of products was studied. In the presence of catalyst, the oil yield was increased, even under conditions where the catalyst did not affect overall lignite conversion. Under the most favorable conditions the oil yield was a little better than that obtained by Cronauer in the uncatalyzed hydroliquefaction of subbituminous coal at similar temperature and pressure.

  11. Tertiary lignites of As Pontes (NW-Spain) - an example for the composition of bright coal layers and its implications for formation

    Energy Technology Data Exchange (ETDEWEB)

    Hagemann, H.W.; Pickel, W. [RWTH Aachen (Germany). Lehrstuhl fuer Geologie, Geochemie und Lagerstaetten des Erdoels und der Kohle; Cabrera, L.; Saez, A. [Barcelona Univ. (Spain). Dept. de Geologia Dinamica, Geofisica i Paleontologia

    1997-12-31

    The Tertiary lignite basin of As Pontes is characterized by the frequent occurrence of bright brown coal layers. These layers, macroscopically very similar to those described for example in the Weisselster Basin and various other lignite deposits were studied in detail mainly by means of organic petrography in one seam of the basin and the data were related to the brightness of the coals. The question, if the colour of lignite is mainly influenced by the original plant input or the depositional environment, is under strong controversial discussion up to now. The bright coals of the As Pontes Basin are mineral rich (especially in clay) and/or contain high amounts of lipid rich matter (liptinite), especially coalification products of cork-tissue (suberinite). The results of the study indicate that the bright coal is highly degraded in comparison to the dark coals of the same basin. The formation of bright, litinite/mineral-rich lignite layers occurred especially during early basin evolution stages influenced by water table oscillations. Sedimentological, petrographical and organic geochemical data point to the fact that, although the paleoenvironments, where peat deposition took place, did not experience drastic changes, they were affected by noticable variations in hydrochemistry and groundwater stability, related to the tectonic historical record of the basin and the paleoclimatic conditions. In summary the origin of the bright layers of the As Pontes lignite is mainly related to the depositional environment. (orig.)

  12. Mathematical analysis of physicochemical phenomena in the catalyst during hydrogenating depolymerization of coal extract benzene insoluble fraction

    Institute of Scientific and Technical Information of China (English)

    Jerzy Szczygieł; Marek Stolarski

    2015-01-01

    Efficiency and selectivity of hydrogenating depolymerization of the coal extract benzene-insoluble part over the heterogeneous Co–Mo/Al2O3 catalyst were assessed using a mathematical model. The analytical equations of the mathematical model were generated based on material balance incorporating the physico-chemical phenomena (reaction and diffusion) both in the autoclave and the catalyst grain. The equations offer the possibility for predicting changes of the reactants in the autoclave during the process and for determining the distribution of reactant concentrations in the grain as a function of its radius. The analytical equations of the model serve as the basis of the algorithm for assessing the influence of restrictive diffusion on the effectiveness and selectivity of the catalyst, and also for defining the optimal radi of the catalyst's pores to enable free transport of reactants in the grain interior.

  13. JV Task 106 - Feasibility of CO2 Capture Technologies for Existing North Dakota Lignite-Fired Pulverized Coal Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Michael L. Jones; Brandon M. Pavlish; Melanie D. Jensen

    2007-05-01

    The goal of this project is to provide a technical review and evaluation of various carbon dioxide (CO{sub 2}) capture technologies, with a focus on the applicability to lignite-fired facilities within North Dakota. The motivation for the project came from the Lignite Energy Council's (LEC's) need to identify the feasibility of CO{sub 2} capture technologies for existing North Dakota lignite-fired, pulverized coal (pc) power plants. A literature review was completed to determine the commercially available technologies as well as to identify emerging CO{sub 2} capture technologies that are currently in the research or demonstration phase. The literature review revealed few commercially available technologies for a coal-fired power plant. CO{sub 2} separation and capture using amine scrubbing have been performed for several years in industry and could be applied to an existing pc-fired power plant. Other promising technologies do exist, but many are still in the research and demonstration phases. Oxyfuel combustion, a technology that has been used in industry for several years to increase boiler efficiency, is in the process of being tailored for CO{sub 2} separation and capture. These two technologies were chosen for evaluation for CO{sub 2} separation and capture from coal-fired power plants. Although oxyfuel combustion is still in the pilot-scale demonstration phase, it was chosen to be evaluated at LEC's request because it is one of the most promising emerging technologies. As part of the evaluation of the two chosen technologies, a conceptual design, a mass and energy balance, and an economic evaluation were completed.

  14. Geochemical and Mineralogical Characteristics of Pleistocene Lignites and Associated Sediments of Marathousa Coal Field,Central Peloponnese,Greece

    Institute of Scientific and Technical Information of China (English)

    A.E.KELEPERTSIS; E.KONTIS

    1997-01-01

    The mineralogy and geochemistry data are presented for thirty-seven shales,four concretions,two carbonate sediments and seven lignites from the Marathousa coal field of the Megalopolis Basin in Greece.The argillaceous rocks consist of chlorite,illite,kaolinte,albite,quartz.opal-A,calcite and dolomite;the concretions of aragonite,gypsum and pyrite;and the carbonate rocks of calcite,quartz and illite.The mineral matter in the lignites consists of gypsum,quartz,albite,chlorite,illite,opal-A,dolomite,pyrite,and rarely calcite and kaolinite Athree-factor model explains the total variaition of major and trace elements in the argillaceous sediments.The first factor is an aluminosilicate factor and involves the following elements:Al,Si,Mg,Na,K,Ti,Mn,Nb,Y,Rb,Zn,Cu,Ni,Cr,Nband V,associated with chlorite,albite and illite.The second factor involves the elements Ca,Sr,Ba,Znand Sc and is related to carbonate lithology and mainly the carbonate concretions with gypsum.The third factor involves Fe and Ce with a weak association with Mn.The diagenesis of the Marathousa sediments and lignites was not very advanced as indicated by (a) the total thickness of the sequence (500m),(b) the presence of biogenic silica(opal-A) and (c) the age of the deposit(Pleistocene).FOr these reasons the rpresence of chlorite,illite and kaolinite in the sediments and lignite is due not to diagenetic reactions but to weathering of the flysch and metamorphic rocks at the edges of the Megalopolis Basin and transport of the weathering products(illite,chlorite,kaolinite)into the basin of deposition.The diagenetic minerals of the Marathousa sequence include pyrite,gypsum,dolomite and aragonite.

  15. The acidophilic microorganisms diversity present in lignite and pit coal from Paroseni, Halânga, Turceni mines

    Directory of Open Access Journals (Sweden)

    Carmen Madalina CISMASIU

    2009-11-01

    Full Text Available Pollution from coal combustion is the largest problem in the current use of coal and the biggest constraint on the increased use of coal. When these fossil fuels are combusted, sulphur-di-oxide is released into the atmosphere causing acid rains which dissolves buildings, kills forest. Knowing the physiological groups of microorganisms present in the coal samples has an ecological importance, completing the knowledge in the field of the microorganism’s ecology and a practical importance, being a source of new microorganisms with biotechnological potential. The microbial communities evidenced in such sites include both groups of chemolithotrophic microorganisms involved in the metals biosolubilization processes and groups of heterotrophic microorganisms involved in the processes of bioaccumulation or biofixation of metallic ions. In this context, this paper presents the study regarding the main physiological groups of microorganisms present in the pit coal and lignite samples after the industrial processing of coal. The results revealed that the microorganisms belonging to the following physiological groups: aerobic heterotrophic acidophilic bacteria, strictly anaerobic heterotrophic (sulphur-reducing, nitrifying bacteria (nitrite and nitrate bacteria, denitrifying bacteria and acidophilic chemolithotrophic bacteria on Fe2+, on S0 and on S2O3.

  16. Depolymerization of coal by O2 oxidation followed by acid hydrolysis; Sanso sanka-kasui bunkai ni yoru sekitan no teionkai jugo

    Energy Technology Data Exchange (ETDEWEB)

    Aizawa, S.; Hayashi, J.; Kumagai, H.; Chiba, T. [Hokkaido University, Sapporo (Japan). Center for Advanced Research of Energy Technology; Morooka, S. [Kyushu University, Fukuoka (Japan). Faculty of Engineering

    1996-10-28

    With an objective to elucidate characteristics of oxygen addition to coal, and characteristics of solvent extraction by means of depolymerization, experiments were performed on oxygen oxidation and acid hydrolysis of brown coals. Coals used for the experiments are Morwell (MW), Yallourn (YL) , South Banko (SB) and Wyoming (WY) coals. Test samples were suspended in weak alkaline aqueous solution, and then oxygen was blown into them with pressure kept at atmospheric pressure. After a lapse of a predetermined time, the samples were cooled, and made as acidic as pH 1.3 in hydrochloric acid, followed by acid hydrolysis. Oxygen consumption increased with the reaction time, and with the MW coal, one mol oxygen reacted to 11 mols of coal. Spectral analysis on the YL and WY coal experiments revealed that aliphatic carbon combined with aromatic carbon or ether group has turned to peroxide, whose C-C or C-O bond was broken down as a result of acid hydrolysis of the peroxide, producing oxygen containing compounds. As a result of the depolymerization, the rate of extraction by using DMF, DMSO and methanol/THF mixed solvent increased to 90% or higher. Proportion of bond and cutting-off affects largely collapse of the cross-link structure. The carbon conversion to volatiles was at most 4%. 1 ref., 10 figs.

  17. Lignite Fuel Enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Charles Bullinger; Nenad Sarunac

    2010-03-31

    Pulverized coal power plants which fire lignites and other low-rank high-moisture coals generally operate with reduced efficiencies and increased stack emissions due to the impacts of high fuel moisture on stack heat loss and pulverizer and fan power. A process that uses plant waste heat sources to evaporate a portion of the fuel moisture from the lignite feedstock in a moving bed fluidized bed dryer (FBD) was developed in the U.S. by a team led by Great River Energy (GRE). The demonstration was conducted with Department of Energy (DOE) funding under DOE Award Number DE-FC26-04NT41763. The objectives of GRE's Lignite Fuel Enhancement project were to demonstrate reduction in lignite moisture content by using heat rejected from the power plant, apply technology at full scale at Coal Creek Station (CCS), and commercialize it. The Coal Creek Project has involved several stages, beginning with lignite drying tests in a laboratory-scale FBD at the Energy Research Center (ERC) and development of theoretical models for predicting dryer performance. Using results from these early stage research efforts, GRE built a 2 ton/hour pilot-scale dryer, and a 75 ton/hour prototype drying system at Coal Creek Station. Operated over a range of drying conditions, the results from the pilot-scale and prototype-scale dryers confirmed the performance of the basic dryer design concept and provided the knowledge base needed to scale the process up to commercial size. Phase 2 of the GRE's Lignite Fuel Enhancement project included design, construction and integration of a full-scale commercial coal drying system (four FBDs per unit) with Coal Creek Units 1 and 2 heat sources and coal handling system. Two series of controlled tests were conducted at Coal Creek Unit 1 with wet and dried lignite to determine effect of dried lignite on unit performance and emissions. Wet lignite was fired during the first, wet baseline, test series conducted in September 2009. The second test series was

  18. Depolymerization of lower rank coals by low-temperature O{sub 2} oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, J.; Matsuo, Y.; Kusakabe, K.; Morooka, S. [Hokkaido University, Sapporo (Japan). Center for Advanced Research of Energy Technology

    1997-01-01

    Four lower rank coals were oxidized in 0.5 N Na{sub 2}CO{sub 3} aqueous solution, into which atmospheric oxygen gas was bubbled. The reaction was carried out at 20-85{degree}C, and, after cooling to ambient temperature, the slurry was acidified (pH 1.3) with a 5 N HCl solution. The coals oxidized at 85{degree}C for 6-24 h were extracted with methanol/tetrahydrofuran mixtures of 25/75 and 50/50 in volume ratio at 30{degree}C under ultrasonic irradiation. The O{sub 2} oxidation dramatically enhanced the extractability of the coals, and extraction yields reached 80-90 wt% daf. Dimethyl sulfoxide and a mixture of benzene and methanol gave similar extraction yields for each oxidized coal. Pyridine showed lower extraction yields in spite of its higher hydrogen-bond-breaking ability. Extractability was, thus, better correlated with the solubility parameter of solvents than with the heat of hydrogen bond complexation. Diffuse reflectance FTIR analysis revealed that the O{sub 2} oxidation introduced carboxylic, phenolic, and alcoholic hydroxyls into the coals with a decrease in alkyl groups and aryl-alkyl ethers. This structural change was due to the oxidation of aliphatic carbon-hydrogen bonds to peroxides and subsequent dissociation by acid-catalyzed hydrolysis. The O{sub 2} oxidation also converted a portion of the coals to water-soluble acids such as oxalic, formic, acetic, and malonic acids and carbon dioxide. The carbon conversion to CO{sub 2} was negligible for the O{sub 2} oxidation at 20-50{degree}C and was 5-9 wt% daf for that at 85{degree}C. 65 refs., 12 figs., 3 tabs.

  19. Qualitative and chemical characteristics of mineral matter in the selected lignite deposits in light of their suitability for clean coal technologies

    Directory of Open Access Journals (Sweden)

    Bielowicz Barbara

    2016-01-01

    Full Text Available An analysis of the variability of ash content and chemical composition of coal ash is crucial when assessing the possibility of using this raw material in clean coal technologies (CCS. The paper focuses on chemical, technological and quality characteristics of ash from the combustion of lignite from Polish deposits. Ash content on a dry ash-free basis for the samples from 9 deposits varies from 1 to 50%. The most commonly observed ash content in the studied samples of lignite is in the range between 10–20%. The measured ash melting temperatures from the collected lignite samples have shown that the sintering, softening, melting and flow temperatures, determined in an oxidizing atmosphere (air, are higher than those determined in a reducing atmosphere. In the majority of Polish lignite deposits, the dominant component of ash was SiO2, followed by CaO. When evaluating the suitability of coal in energy production, with particular emphasis on the combustion and gasification processes, it is also necessary to study the behavior of ash at high temperatures and the impact of ash on the gasification and combustion facilities. Ash fouling and slagging processes, which are heavily dependent on the ash content, composition, melting point and the content of chlorine, phosphorus and sulfur in coal, have a negative effect on the combustion process.

  20. The spatial distribution of the lignite qualitative parameters and variant estimates of coal reserves: the Czech Part of the Vienna Basin

    Science.gov (United States)

    Jelínek, Jan; Staněk, František; Vebr, Lukáš; Honěk, Josef

    2014-06-01

    The aim of this article is to inform about the spatial distribution of the lignite qualitative parameters and total lignite reserves in the Czech Part of the Vienna Basin—The South Moravian Lignite Coalfield (SMLC). The total reserves were estimated on the basis of several composed variant digital models of individual seams in four partial area of SMLC. Calculations of the reserves resulted from the identified spatial distribution of chemical-technological parameters obtained from the thousands analysis of samples taken from more than 4,000 exploration works. The basic model of the deposit was so-called geological model characterising genetic evolution of the deposit and defines the spatial positions of the coal seams. Subsequently developed variant economical models spatially define the selected areas by the quality of lignite expressed by the limits of ash yield. Based on the created models, it was found that in the past just 3-7 % (depending on the variant model) of the total lignite reserves SMLC had been extracted. The presented geological reserves are currently using the existing mining technologies only partially mineable.

  1. Liquefaction/solubilization processes of Spanish coals by microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Laborda, F.; Monistrol, I.F.; Luna, N.; Fernandez, M. [Madrid Univ. (Spain). Dept. de Microbiologia y Parasitologia

    1997-12-31

    Several fundamental aspects of microbial coal liquefaction/solubilization have been studied in this work. The first one is the mechanisms implicated on coal transformation. During coal solubilization, fungal cells produced extracellular peroxidase, esterase and some times phenol oxidase enzymes which appear to be involved in solubilization. Moreover, the analysis of liquefaction/solubilization products was done. In this regard, a reduction on the average size of humic acids derived from lignite was observed, probably due to depolymerization caused by microorganisms. Finally, microorganisms showed a specific adherence to the coal surface, that seems to promote the microbial attack to coal. (orig.)

  2. Processes of liquefaction/solubilization of Spanish coals by microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Laborda, F.; Monistrol, I.F.; Luna, N.; Fernandez, M. [Universidad de Alcala de Henares, Madrid (Spain). Dept. de Microbiologia y Parasitologia

    1999-07-01

    Several fundamental aspects of microbial coal liquefaction/solubilization were studied. The liquefied/solubilized products from coal by microorganisms were analysed. The liquid products analysed by IR titration and UV/visible spectrometry showed some alterations with regard to the original coal. Humic acids extracted from the liquefied lignite showed a reduction in the average molecular weight and a increase in the condensation index, probably due to depolymerization caused by microorganisms. The mechanisms implicated in coal biosolubilization by two fungal strains, M2 (Trichoderma sp.) and M4 (Penicillium sp.) were also studied. Extracellular peroxidase, esterase and phenoloxidase enzymes appear to be involved in coal solubilization. (orig.)

  3. Parameters determining the carbon isotopic composition of coal and fossil wood in the Early Miocene Oberdorf lignite seam (Styrian Basin, Austria)

    Energy Technology Data Exchange (ETDEWEB)

    Bechtel, A.; Sachsenhofer, R.F.; Gratzer, R.; Lucke, A.; Puttmann, W. [University of Leoben, Leoben (Austria)

    2002-07-01

    Petrographical and geochemical data of gelified and ungelified fossil wood from the Early Miocene Oberdorf lignite seam (Styrian Basin, Austria) provide evidence that the early diagenetic, aerobic degradation of wood by fungi may be followed by further decomposition under reducing conditions by the activity of anaerobic bacteria. Based on the molecular compositions of terpenoid hydrocarbons, the wood fragments in the lignite are identified as gymnosperms. The mean carbon isotope values found for gymnosperms and coals (-24.2 parts per thousand and -24.7 parts per thousand, respectively) confirm the results from biomarker analyses indicating that the peat-forming vegetation of the Oberdorf seam was dominated by gymnosperm taxa. The results obtained from the Early Miocene Oberdorf lignite indicate that the carbon isotope ratios of the coals are primarily affected by varying contributions of different parts of whole-plant tissue, due to their different isotopic and molecular compositions (e.g. epicuticular leaf waxes, resins, wood) and their different decay-resistance against the early diagenetic changes involved in organic matter decomposition. Carbon cycling during anoxic decomposition of plant-derived organic matter is assumed to affect the {delta}-{sup 13}C values of coal. {delta}-{sup 13}C Values of wood and extracted cellulose are affected only to a minor extent.

  4. Influence of floral assemblage, facies and diagenesis on petrography and organic geochemistry of the Eocene Bourgas coal and the Miocene Maritza-East lignite (Bulgaria)

    Energy Technology Data Exchange (ETDEWEB)

    Bechtel, A.; Sachsenhofer, R.F.; Zdravkov, A.; Kostova, I.; Gratzer, R. [University of Leoben, Leoben (Austria)

    2005-07-01

    Numerous differences in the petrography and organic geochemistry of two Tertiary, low rank coal deposits of Bulgaria, formed within comparable depositional environments, are outlined. Different floral assemblages are indicated as the main sources of organic matter. For the Eocene Bourgas sub-bituminous coals a warm climate plant community dominated by angiosperms is reflected in the biomarker composition, whereas a coniferous flora was the main source of the resinous organic matter of the Miocene Maritza-East lignite. The results are in agreement with palaeobotanical data. These differences in the peat forming vegetation of the Paleogene compared to the Neogene of Bulgaria are attributed to decreasing temperature during the Tertiary.

  5. Mineral composition of rock in Visonia lignite and Nograd brown coal and its influence on abradability

    Energy Technology Data Exchange (ETDEWEB)

    Szalay, Z.

    1984-01-01

    A study is made of the properties of coals when they are reprocessed in a crusher and tubular furnace at the Gagarin heat and electric power plant and the characteristics of the forming fly ash. The coals are distinguished by high percentages (15-28%) of montmorillonite and kaolinite (3-13%). DTA and x-ray structural analysis of the coals and solid residues were conducted. It is shown that the fly ash is mainly formed from clay minerals and consists of an amorphous mass and modifications of free SiO/sub 2/.

  6. Computer controlled measurement of spontaneous combustion in coal stockpiles of the Western Lignite Corporation, Turkey

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The spontaneous combustion event in coal stockpiles is inevitable when appropriate environmental conditions are available.The objective of a computerized measurement system is to measure temperature changes existing in a coal stockpile.In order to achieve this intention, the electrical signal conversion of temperatures sensed by 20 temperature sensors placed in certain points inside the coal stockpile, the transfer of these electrical signals into computer media by using analogue-digital conversion unit after applying necessary filterization and upgrading processes and the record of these information into a database in particular time intervals are provided.Afterwards, the diagrams of these time-temperature data are plotted.With the help of these graphs, the competent company will be able to examine the behavior of coal stockpiles in terms of spontaneous combustion and take necessary precautions against self-combustion beforehand.

  7. Reduction of sulfur content of brown coals and lignites by hydrothermal treatment

    Energy Technology Data Exchange (ETDEWEB)

    Takacs, P.; Wolf, G.; Bognar, T.

    1987-01-01

    The hydrothermal experiments were carried out in acid-proof autoclaves. The experimental conditions are described and the results are summarized for different coal types. The heat treatment reduces the organic sulfur content and increases the calorific value. From 300 degrees C the pyritic sulfur can be separated from the other forms of sulfur. By the hydrothermal treatment the bitumen content to be extracted by benzene-alcohol mixture also increased in thermo-coals.

  8. Biosolubilisation of Chinese lignite

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Sudong; Tan, Zhongchao [Department of Mechanical and Manufacturing Engineering, Schulich School of Engineering, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Tao, Xiuxiang; Shi, Kaiyi [School of Chemical Engineering, China University of Mining and Technology, Xuzhou 221008 (China)

    2009-06-15

    The biosolubilisation of coal is a promising coal processing technology for converting solid coal to liquid oil at ambient conditions. In this study, the biosolubilisation of Chinese lignite was studied using a fungus isolated from decaying wood. The intensity of biosolubilisation was determined by estimating the liquid formation time and by measuring the weight loss of the lignite granules gravimetrically. The biosolubilisation product (black liquid) was characterized by ultraviolet spectroscopy, infrared spectroscopy, gas chromatography-mass spectrometry, element analysis, and heating value. Results showed that this fungus isolated from the decaying wood solubilised 31.83% (by weight) of Chinese lignite to black liquid within 11 days at 27.5 C. The biosolubilisation product mainly contained aromatic acids and chain hydrocarbons, and had organic function groups of hydroxyl, cyclane, carbonyl, ether linkage and aromatic rings. The heating value of the biosolubilisation product was 14 MJ/kg. Chemical analysis of the biosolubilisation product indicated that side chains of lignite were important structures in the biosolubilisation mechanism. (author)

  9. Characterization of Coals and Lignites by Thermo-Magneto-Gravimetric Analysis.

    Science.gov (United States)

    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)

  10. JV TASK 45-MERCURY CONTROL TECHNOLOGIES FOR ELECTRIC UTILITIES BURNING LIGNITE COAL, PHASE I BENCH-AND PILOT-SCALE TESTING

    Energy Technology Data Exchange (ETDEWEB)

    John H. Pavlish; Michael J. Holmes; Steven A. Benson; Charlene R. Crocker; Edwin S. Olson; Kevin C. Galbreath; Ye Zhuang; Brandon M. Pavlish

    2003-10-01

    The Energy & Environmental Research Center has completed the first phase of a 3-year, two-phase consortium project to develop and demonstrate mercury control technologies for utilities that burn lignite coal. The overall project goal is to maintain the viability of lignite-based energy production by providing utilities with low-cost options for meeting future mercury regulations. Phase I objectives are to develop a better understanding of mercury interactions with flue gas constituents, test a range of sorbent-based technologies targeted at removing elemental mercury (Hg{sup o}) from flue gases, and demonstrate the effectiveness of the most promising technologies at the pilot scale. The Phase II objectives are to demonstrate and quantify sorbent technology effectiveness, performance, and cost at a sponsor-owned and operated power plant. Phase I results are presented in this report along with a brief overview of the Phase II plans. Bench-scale testing provided information on mercury interactions with flue gas constituents and relative performances of the various sorbents. Activated carbons were prepared from relatively high-sodium lignites by carbonization at 400 C (752 F), followed by steam activation at 750 C (1382 F) and 800 C (1472 F). Luscar char was also steam-activated at these conditions. These lignite-based activated carbons, along with commercially available DARCO FGD and an oxidized calcium silicate, were tested in a thin-film, fixed-bed, bench-scale reactor using a simulated lignitic flue gas consisting of 10 {micro}g/Nm{sup 3} Hg{sup 0}, 6% O{sub 2}, 12% CO{sub 2}, 15% H{sub 2}O, 580 ppm SO{sub 2}, 120 ppm NO, 6 ppm NO{sub 2}, and 1 ppm HCl in N{sub 2}. All of the lignite-based activated (750 C, 1382 F) carbons required a 30-45-minute conditioning period in the simulated lignite flue gas before they exhibited good mercury sorption capacities. The unactivated Luscar char and oxidized calcium silicate were ineffective in capturing mercury. Lignite

  11. REMOVAL OF ASTROZON RED FROM AQUEOUS SOLUTIONS BY THE ADSORBENTS PRODUCED FROM LIGNITE COAL

    Directory of Open Access Journals (Sweden)

    Mehmet MAHRAMANLIOĞLU

    2002-01-01

    Full Text Available The adsorption of Astrozone Red on the activated coal from aqueous solutions was studied.The adsorption process followed the Lagergren first order kinetics equation. The adsorbent concentration affected the adsorption of Astrozone Red significiantly.The equilibrium data fit well in the Langmuir model and isotherm constants were calculated. The adsorption of Astrozon Red increased with increase of the pH value in the solution.The thermodynamics of adsorption indicated spontaneous and exothermic nature of the process.

  12. Catalytic cracking of lignites

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, M.; Nowak, S.; Naegler, T.; Zimmermann, J. [Hochschule Merseburg (Germany); Welscher, J.; Schwieger, W. [Erlangen-Nuernberg Univ. (Germany); Hahn, T. [Halle-Wittenberg Univ., Halle (Germany)

    2013-11-01

    A most important factor for the chemical industry is the availability of cheap raw materials. As the oil price of crude oil is rising alternative feedstocks like coal are coming into focus. This work, the catalytic cracking of lignite is part of the alliance ibi (innovative Braunkohlenintegration) to use lignite as a raw material to produce chemicals. With this new one step process without an input of external hydrogen, mostly propylene, butenes and aromatics and char are formed. The product yield depends on manifold process parameters. The use of acid catalysts (zeolites like MFI) shows the highest amount of the desired products. Hydrogen rich lignites with a molar H/C ratio of > 1 are to be favoured. Due to primary cracking and secondary reactions the ratio between catalyst and lignite, temperature and residence time are the most important parameter to control the product distribution. Experiments at 500 C in a discontinuous rotary kiln reactor show yields up to 32 wt-% of hydrocarbons per lignite (maf - moisture and ash free) and 43 wt-% char, which can be gasified. Particularly, the yields of propylene and butenes as main products can be enhanced four times to about 8 wt-% by the use of catalysts while the tar yield decreases. In order to develop this innovative process catalyst systems fixed on beads were developed for an easy separation and regeneration of the used catalyst from the formed char. (orig.)

  13. Biodesulfurization of Cayirhan lignites

    Energy Technology Data Exchange (ETDEWEB)

    Guru, M.; Cubuk, M.; Dursun, S.; Demirbas, A. [Gazi University, Maltepe (Turkey). Dept. of Chemical Engineering

    2006-04-15

    In this study, the lignite was improved oxidizing sulfur compounds by Thiobacillus thiooxidans and Thiobacillus ferrooxidans bacteria. Experiments in the batch reactors have been carried out 20% aqueous suspension of coal samples. Sugar beet molasses was used as the bacterial substrate. The maximum removal of combustible sulfur was obtained as 78.2% under the following conditions; addition 5% of T. thiooxidans and 5% T. ferrooxidans into coal suspension, 0.2 g molasses/g coal change, pH value of 3, at shaking rate of 70 rpm and at 40{sup o}C for 5 days.

  14. Lignite oxidative desulphurization

    Institute of Scientific and Technical Information of China (English)

    Volodymyr Gunka; Serhiy Pyshyev

    2014-01-01

    The process of lignite desulphurization via its treatment by an oxidant (air or air–steam mixture) has been studied. The research objective was useful determination of steam application in oxidative lignite desulphurization. It has been proved that the water steam should be included in the oxidant composition to increase the hydrogen sulphide and combustible constituent content in the gases obtained during the processes under research. The impact of factors which affect the reactions between solid (in our case–lignite) and gaseous reagent (oxidant, i.e. air and or air–steam mixture) upon the research process has been investigated, if these reactions occur in the kinetic area. Such factors are linear rate of oxidant movement and coal grain size. The values of oxidant movement linear rate and coal grain size, which the reaction transfer from pyrite sulphur and organic content of lignite from diffusion into kinetic area occurs by, have been determined. Under these‘‘transfer’’ conditions, the values of coefficients of oxidant mass transfer (b, m/s) as well as Sherwood criteria and boiling layer differences have been calculated.

  15. New method for the simultaneous determination of pyrite content and proximate analysis in coal and lignite

    Energy Technology Data Exchange (ETDEWEB)

    Aylmer, D.M.

    1983-01-01

    The new method combines thermogravimetry and thermomagnetometry and utilizes inert, oxidizing, and reducing gases. Results by the new technique are compared to the ASTM method, one set obtained by the author on a Fisher Coal Analyzer and one set by the Coal Research Laboratory of the Pennsylvania State University. Comparison of thermo-magneto-gravimetric-analysis with the ASTM method indicates good agreement and comparable accuracy. These studies show that the thermo-magneto-gravimetric-analysis are: 1) ease of determination of both proximate analysis and pyrite, which permits use of unskilled technicians; 2) widespread availability of the apparatus; 3) cost effectiveness due to use of unskilled operators; 4) automation, presently available for proximate analysis on some commercial instruments and is easily accomplished for pyrite analysis, as well; 5) advantage over pyrite analysis by the ASTM method in two situations: first, when pyrite is totally surrounded by acid-insoluble organic-material and secondly where significant amounts of pyrite have been oxidized to FeSO/sub 4/; and 6) a permanent record of the measurements, which are continuous, is made in contrast to the ASTM method which records only initial and final conditions.

  16. Recovery of germanium from lignite by microorganism

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The recovery of Ge from lignite by microorganism includes two stages: (1) the breaking-down of Ge complex of humus in lignite into simple compounds assisted by microorganism; (2) the desorption of Ge compounds from the lignite. The recovery rate of Ge has been enhanced by 14% since the discovery of adsorption and desorption of Ge from coal. The effects of pH, leaching agents, and coal size on the recovery of Ge were experimentally investigated, and the optimized process parameters were obtained. The reaction heat of Ge adsorption and desorption in lignite was determined. It is about 23-53 kJ/mol, which reveals that the adsorption belongs to physical process. The recovery rate of Ge from lignite with direct microorganism leaching can reach about 85%, which is higher than that of 60% reported elsewhere. A potential process for leaching Ge in lignite was suggested.

  17. 基于Aspen Plus的褐煤热解过程模拟%The Lignite Coal Pyrolysis Process Simulation Based on Aspen Plus

    Institute of Scientific and Technical Information of China (English)

    王伟; 商玉坤; 武建军

    2011-01-01

    With high moisture lignite coal as an example, the method and procedure to build simplified model for coal pyrogenation process (CPD) using the chemical process simulation software Aspen Plus were introduced. Setting process of CPD model simulation parameter was given, and the Aspen Plus software was used to simulate the calculation process of coal pyrogenation, and the obtained simulation value was compared with the actual value. At the same time, the coal pyrolysis simulation process and the results were analyzed and provided basic reference to coal pyrogenation process development and optimization.%以高水分褐煤为例,介绍了利用Aspen Plus化工流程模拟软件建立煤热解过程简化模型的方法及步骤.阐述了CPD模型模拟参数的设置过程,并利用Aspen Plus软件对煤热解过程进行了模拟计算,将得出的模拟值与实际值进行了比较.同时,对煤热解模拟过程及结果进行了分析,给煤热解过程的工艺开发和工艺优化提供了参考依据.

  18. Lignite microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Bulankina, M.A.; Lysak, L.V.; Zvyagintsev, D.G. [Moscow MV Lomonosov State University, Moscow (Russian Federation). Faculty of Soil Science

    2007-03-15

    The first demonstration that samples of lignite at a depth of 10 m are considerably enriched in bacteria is reported. According to direct microscopy, the abundance of bacteria was about 10{sup 7} cells/g. About 70% of cells had intact cell membranes and small size, which points to their anabiotic state. The fungal mycelium length was no more than 1 m. Lignite inoculation onto solid glucose-yeast-peptone medium allowed us to isolate bacteria of the genera Bacillus, Rhodococcus, Arthrobacter, Micrococcus, Spirillum, and Cytophaga. Representatives of the genera Penicillium and Trichoderma were identified on Czapek medium. Moistening of lignite powder increased the microbial respiration rate and microbial and fungal abundance but did not increase their generic diversity. This finding suggests that the studied microorganisms are autochthonous to lignite.

  19. Effect of biomass-sulfur interaction on ash composition and agglomeration for the co-combustion of high-sulfur lignite coals and olive cake in a circulating fluidized bed combustor.

    Science.gov (United States)

    Varol, Murat; Atimtay, Aysel T

    2015-12-01

    This study aimed to investigate the effect of biomass-sulfur interaction on ash composition and agglomeration for the co-combustion of high-sulfur lignite coals and olive cake in a circulating fluidized bed combustor. The tests included co-combustion of 50-50% by wt. mixtures of Bursa-Orhaneli lignite+olive cake and Denizli-Kale lignite+olive cake, with and without limestone addition. Ash samples were subjected to XRF, XRD and SEM/EDS analyses. While MgO was high in the bottom ash for Bursa-Orhaneli lignite and olive cake mixture, Al2O3 was high for Denizli-Kale lignite and olive cake mixture. Due to high Al2O3 content, Muscovite was the dominant phase in the bottom ash of Denizli Kale. CaO in the bottom ash has increased for both fuel mixtures due to limestone addition. K was in Arcanite phase in the co-combustion test of Bursa/Orhaneli lignite and olive cake, however, it mostly appeared in Potassium Calcium Sulfate phase with limestone addition.

  20. THE COMBUSTION CHARACTERISTICS OF LIGNITE BLENDS

    Institute of Scientific and Technical Information of China (English)

    Cheng Jun; Zhou Junhu; Cao Xinyu; Cen Kefa

    2000-01-01

    The combustion characteristics of lignite blends were studied with a thermogravimetric analyzer (t.g.a.), at constant heating rate.The characteristic temperatures were determined from the burning profiles.It was found that the characteristic times of combustion reaction moved forward, the ignition temperature dropped and the burnout efficiency slightly changed when blending lignites.The characteristic parameters of blends could not be predicted as a linear function of the average values of the individual lignites.when blending with less reactive coal, the ignition and burnout characteristics of lignite turned worse.

  1. Solubilization of lignite and behavior of oxygen containing functional groups in coal with superacid; Chokyosan wo mochiita kattan no kayoka oyobi sanso kannoki no kyodo

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, K.; Saito, I. [National Institute for Resources and Environment, Tsukuba (Japan); Sasaki, S.; Suganuma, A. [Science University of Tokyo, Tokyo (Japan). Faculty of Science and Technology

    1996-10-28

    Solubilization of lignite including a large amount of oxygen containing functional groups was attempted using HF/BF3, and the behavior of oxygen containing functional group, one of the important factors for coal liquefaction, was studied. In experiment, the cooled slurry of Yallourn coal specimen and solvent (toluene, isopentane) was filled into a vacuum autoclave together with HF/BF3. Reaction was performed under spontaneous pressure at 50, 100 or 150{degree}C for 3 hours. The distribution of oxygen containing functional groups in each coal specimen was determined by quantification of carboxyl group, hydroxyl group and carbonyl group. As the experimental result, the superacid mixture of HF and BF3 considerably improved the solubility of coal specimens into solvent as compared with individual HF and BF3. The solubility was 68wt% into benzene, 96% into THF and 99% (nearly 100%) into pyridine. It was suggested that production of Broensted acid with strong acidity causes strong catalysis. 6 refs., 2 figs., 1 tab.

  2. Vegetation differences and diagenetic changes between two Bulgarian lignite deposits - Insights from coal petrology and biomarker composition

    Energy Technology Data Exchange (ETDEWEB)

    Zdravkov, A.; Bechtel, A.; Sachsenhofer, R.F.; Kortenski, J.; Gratzer, R. [University of Mining & Geology St Ivan Rilski, Sofia (Bulgaria)

    2011-03-15

    In this study, we review the petrographic composition and biomarker assemblage of two adjacent basins in western Bulgaria, i.e. Beli Breg and Staniantsi basins. Both contain lignite formed during late Miocene (c. 6 Ma). Despite similar tectonic settings and depositional environments, the lignite seams possess different petrographic and organic geochemical characteristics, reflecting differences in the peat forming palaeo-communities and fades variations. The peat-forming vegetation in Bell Breg Basin was dominated by decay resistant coniferous plants, as indicated by abundant fossil wood remains, very good tissue preservation and a biomarker assemblage dominated by diterpenoids. In contrast, Staniantsi lignite is poor in fossil wood and contains a significant amount of triterpenoid biomarkers, suggesting the predominance of angiosperm plants in the swamp. The results of the biomarker analyses are consistent with palaeobotanical and palynological data from the literature. The lignite seams in both basins formed under frequently changing Eh conditions, as indicated by the severe degradation of the non-gymnosperm tissues, the low gelification index values and the variations in pristane/phytane ratio, probably as a result of seasonal drying of the swamps and changes of the ground water table. Hopanoid contents in Bell Breg lignite are very low and are consistent with the abundance of decay-resistant vegetation. In contrast, bacterial activity was obviously higher in the Staniantsi swamp, however, resulting only in slightly enhanced gelification of plant tissues. The geochemical data suggest that the diagenetic changes of the organic matter were mainly governed by thermal degradation, rather than bacterial activity.

  3. Lignite; Braunkohle

    Energy Technology Data Exchange (ETDEWEB)

    Kaltenbach, Erwin; Maassen, Uwe [Debriv e.V., Berlin und Koeln (Germany)

    2015-07-01

    The domestic lignite is the most important and in the foreseeable future, the only domestic energy resource that is available in large quantities and economically. It makes an essential contribution to secure and competitive energy supply and has a high regional as macroeconomic importance. The required guarantied capacity for the development of renewable energy, the lignite provides under competition conditions. The flexibility of the lignite power plants is in addition to security of supply and competitiveness, a strategic added value for a reliable power supply. [German] Die heimische Braunkohle ist die wichtigste und in ueberschaubarer Zukunft auch die einzige heimische Energieressource, die in grossen Mengen und wirtschaftlich zur Verfuegung steht. Sie leistet einen unverzichtbaren Beitrag zur sicheren und wettbewerbsfaehigen Energieversorgung und hat eine hohe regional- wie gesamtwirtschaftliche Bedeutung. Die fuer den Ausbau der erneuerbaren Energien notwendige gesicherte Leistung stellt die Braunkohle unter Wettbewerbsbedingungen zur Verfuegung. Die Flexibilitaet des Braunkohlenkraftwerksparks ist neben Versorgungssicherheit und Wettbewerbsfaehigkeit ein strategischer Zusatznutzen fuer eine sichere Stromversorgung.

  4. Measurement of gas species, temperatures, coal burnout, and wall heat fluxes in a 200 MWe lignite-fired boiler with different overfire air damper openings

    Energy Technology Data Exchange (ETDEWEB)

    Jianping Jing; Zhengqi Li; Guangkui Liu; Zhichao Chen; Chunlong Liu [Harbin Institute of Technology, Harbin (China). School of Energy Science and Engineering

    2009-07-15

    Measurements were performed on a 200 MWe, wall-fired, lignite utility boiler. For different overfire air (OFA) damper openings, the gas temperature, gas species concentration, coal burnout, release rates of components (C, H, and N), furnace temperature, and heat flux and boiler efficiency were measured. Cold air experiments for a single burner were conducted in the laboratory. The double-swirl flow pulverized-coal burner has two ring recirculation zones starting in the secondary air region in the burner. As the secondary air flow increases, the axial velocity of air flow increases, the maxima of radial velocity, tangential velocity and turbulence intensity all increase, and the swirl intensity of air flow and the size of recirculation zones increase slightly. In the central region of the burner, as the OFA damper opening widens, the gas temperature and CO concentration increase, while the O{sub 2} concentration, NOx concentration, coal burnout, and release rates of components (C, H, and N) decrease, and coal particles ignite earlier. In the secondary air region of the burner, the O{sub 2} concentration, NOx concentration, coal burnout, and release rates of components (C, H, and N) decrease, and the gas temperature and CO concentration vary slightly. In the sidewall region, the gas temperature, O{sub 2} concentration, and NOx concentration decrease, while the CO concentration increases and the gas temperature varies slightly. The furnace temperature and heat flux in the main burning region decrease appreciably, but increase slightly in the burnout region. The NOx emission decreases from 1203.6 mg/m{sup 3} (6% O{sub 2}) for a damper opening of 0% to 511.7 mg/m{sup 3} (6% O{sub 2}) for a damper opening of 80% and the boiler efficiency decreases from 92.59 to 91.9%. 15 refs., 17 figs., 3 tabs.

  5. Separation and analysis of lignite bioconversion products

    Institute of Scientific and Technical Information of China (English)

    Yao Jinghua; Xiao Lei; Wang Liqiang

    2012-01-01

    The bioconversion of coal at ambient conditions is a promising technology for coal processing,although the mechanisms of coal degradation are still not understood fully.In this work,the bioconversion of lignite was studied using a fungus isolated from decaying wood.The lignite samples were oxidized with nitric acid under moderate conditions and then the oxidized samples were placed on a potato medium with isolated fungus for lignite bioconversion.Lignite,oxidized lignite and residual products after bioconversion of lignite were sequentially extracted with petroleum ether,CS2.methanol,acetone and tetrahydrofuran (THF),and then each extract was characterized by gas chromatography-mass spectrometry (GC/MS).The differences in composition and structure among the samples were inferred by comparing the differences between the extracts.The results show that aromatics with one or several benzene rings and their derivatives; and some long-chain alkanes containing oxygen decreased in the methanol-,acetone-,and THF-soluble fraction from residual lignite,whereas long chain or a few branched alkanes and small quantities of aromatic compounds increased in petroleum ether and CS2 soluble fractions.

  6. The phytosociological method of evaluating recultivation conditions and reforce station of lands that are unsuitable for use based on the lignite coal quarry Adamow (Poland)

    Energy Technology Data Exchange (ETDEWEB)

    Krzaklewski, W.

    1979-01-01

    The rapid elementary covering by plant growth of recently cultivated slopes on an external lignite coal quarry dump ground of Adamov was used in conducting these studies. It is located 7 kilometers from the city Turek. Our assignment was to demonstrate the possibility of using this growth to evaluate the degree of fertility of soils on slopes. The object of our study was southeastern slopes with an area of 20 hectares. The biological recultivation consisted of the initial introduction of fertilizer and sowing with seeds, planting tree seedlings and additional introduction of nitrogen fertilizer. The studies included phytosociology, taking samples of soil and leaves and measuring the seedling grove. Based on a map of the elemental growth compiled in the intial phase of the investigation we selected 14 test plots with an area of 0.01 hectares each, on which we carried out direct observations. In order to evaluate the results we used statistical analysis. In order to determine and evaluate the degree of fertility of soils in the initial stage of their growth, the most important indicators were: degree of cover of the slopes by plant matter for the recognition of localities, which promote and which do not promote the growth of plants; the predominant plants, and above all, the number of Tussilago farfara.

  7. Extraction of lignite coal fly ash for polynuclear aromatic hydrocarbons: modified and unmodified supercritical fluid extraction, enhanced-fluidity solvents, and accelerated solvent extraction.

    Science.gov (United States)

    Kenny, D V; Olesik, S V

    1998-02-01

    A comparison among modified and unmodified supercritical fluid extraction (SFE), enhanced-fluidity liquid extraction, and accelerated solvent extraction (ASE) techniques was made for the extraction of polynuclear aromatic hydrocarbons (PAHs) from an aged, spiked lignite coal fly ash. All of the attempted extraction conditions allowed the extraction of the PAHs to some degree, but no single extraction technique proved to be superior for all of the PAHs used. Three groups of PAHs with similar extraction efficiencies were identified. The group with the lowest molecular weights was best recovered using a 90% CO2-10% methanol mixture at 70 degrees C and 238 atm. The group of medium-molecular-weight PAHs was recovered equally well using any of three extraction conditions: SFE (100% CO2, 90 degrees C, and 238 atm), enhanced-fluidity liquid mixture (60% CO2-40% methanol, 70 degrees C, and 238 atm), and a methanol ASE mixture. The group of high-molecular-weight PAHs seemed to be equally well recovered with all of the attempted extraction conditions, but the enhanced-fluidity conditions (60% CO2-40% methanol, 70 degrees C, and 238 atm) had extraction recoveries (> 85%) with the lowest standard deviations (approximately 5%).

  8. Solubilization of Australian lignites by fungi and other microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Catcheside, D.E.A.; Mallett, K.J. (Flinders University, Bedford Park, SA (Australia). School of Biological Sciences)

    Lignites (brown coals) from the Latrobe Valley in Victoria are solubilized by {ital Coriolus versicolor}, {ital Phanerochaete chrysosporium}, and five other species known to be active on Leonardite and various acid-treated North America lignites. Run-of-mine coal from Morwell and Loy Yang is refractory but is soluble after pretreatment with acid. A weathered deposit at Loy Yang, like Leonardite, is susceptible to biosolubilization without pretreatment. The white rot fungi {ital Ganoderma applanatum}, {ital Perenniporia tephropora} ({ital Fomes lividus}), {ital Pleurotus ostreatus}, {ital Pycnoporus cinnabarinus}, {ital Rigidoporus ulmarius}, and {ital Xylaria hypoxylon} were found to be capable of solubilizing lignite. In contrast, brown rot fungi were weakly active or inactive under the same test conditions. Lignite-degrading fungi, actinomycetes, and other bacteria, including some active on untreated run-of-mine coal, were isolated from natural lignite exposures and mining sites. 15 refs., 5 tabs.

  9. A 90 m-thick coal seam in the Lubstow lignite deposit (Central Poland): palynological analysis and sedimentary environment

    Energy Technology Data Exchange (ETDEWEB)

    Durska, E. [University of Warsaw, Warsaw (Poland). Faculty of Geology

    2008-07-01

    A 90 m-thick brown coal seam, the result of organic matter deposition in a fault-trough, is exploited in an open cast mine at Lubstow (Central Poland). Palynological analysis was conducted in order to determine which plants were the source of organic matter forming such a thick coal bed. The pollen spectrum is dominated by the gymnosperm pollen Inaperturopollenites, produced by trees closely related to the extant genera Taxodium and Glyptostrobus, the dominant constituents of swamp forests in SE North America and SE Asia today. However the lack of xylites and preserved tissues in the coal does not support the conception of a swamp forest as the peat-producing community. There is also significant percentage of angiosperm pollen in the coal, mainly from the groups: Castaneoideapollis, Tricolporopollenites exactus and T. pseudocingulum. The plants producing these pollen were probably the main constitutent of the peat-producing community. The community shows signs of a shrub swamp with local tree islands and a low water table. Evidence for this also includes the detrital type of coal, the lack of preserved plant tissues and the presence of fungal remains. The characteristics show the existence of aerobic zones at the time of peat production. The peat was probably derived from angiosperms. Dome-shaped forms in the upper part of the deposit are the remains of tree islands. As detritus accumulation is very on the surfaces of present-day tree islands, a similar rate of deposition may have taken place during peat production at Lubstow. This, combined with subsidence in the fault-through, explains the great thickness of the coal bed.

  10. Analysis of lithofacies cyclicity in the Miocene Coal Complex of the Bełchatów lignite deposit, south-central Poland

    Directory of Open Access Journals (Sweden)

    Mastej Wojciech

    2015-12-01

    Full Text Available Markov chain analysis was applied to studies of cyclic sedimentation in the Coal Complex of the Bełchatów mining field (part of the Bełchatów lignite deposit. The majority of ambiguous results of statistical testing that were caused by weak, statistically undetectable advantage of either cyclicity over environmental barriers or vice versa, could be explained if only the above-mentioned advantages appeared in the neighbourhood. Therefore, in order to enhance the credibility of statistical tests, a new approach is proposed here in that matrices of observed transition numbers from different boreholes should be added to increase statistical reliability if they originated in a homogeneous area. A second new approach, which consists of revealing statistically undetectable cyclicity of lithofacies alternations, is proposed as well. All data were derived from the mining data base in which differentiation between lithology and sedimentary environments was rather weak. For this reason, the methodological proposals are much more important than details of the sedimentation model in the present paper. Nevertheless, they did reveal some interesting phenomena which may prove important in the reconstruction of peat/lignite environmental conditions. First of all, the presence of cyclicity in the sedimentation model, i.e., cyclic alternation of channel and overbank deposits, represents a fluvial environment. It was also confirmed that the lacustrine subenvironment was cut off from a supply of clastic material by various types of mire barriers. Additionally, our analysis revealed new facts: (i these barriers also existed between lakes in which either carbonate or clay sedimentation predominated; (ii there was no barrier between rivers and lakes in which clay sedimentation predominated; (iii barriers were less efficient in alluvial fan areas but were perfectly tight in regions of phytogenic or carbonate sedimentation; (iv groundwater, rather than surface flow

  11. 78 FR 63463 - Intent To Prepare a Regional Environmental Impact Statement for Surface Coal and Lignite Mining...

    Science.gov (United States)

    2013-10-24

    ... associated with a decision to develop and assess data and information with waters of the United States and... expansions in the state of Texas within the Fort Worth District's area of responsibility. These coal and..., Fort Worth District, P.O. Box 17300, 819 Taylor Street, Fort Worth, Texas 76102; or Darvin.Messer@usace...

  12. 电厂锅炉掺烧褐煤和印尼煤的经济性分析%Economic Analysis of Blending Lignitous Coal and Indonesia Coal for the Power Plant Boiler

    Institute of Scientific and Technical Information of China (English)

    王祝成

    2012-01-01

    由于火力发电的燃料成本约占发电成本的70%以上,且近年来煤炭价格不断上涨,火电企业利润大幅下降,出现行业性亏损。为改善火电企业经营状况,许多火电厂正在掺烧非设计的、价格相对较低的煤种,介绍了国内某电厂掺烧褐煤和印尼煤的概况和具体实施方案,研究了不同掺烧煤种方案对锅炉效率的影响,并对产生的经济效益进行分析,为同类型电厂提供有益参考。%The fuel cost accounts for over 70% the total generating cost. With the continuous roaring of the coal price, the profit of the thermal power enterprises has decreased substantially and as a result the whole thermal power industry even operates in loss. In order to improve this operation situation, some thermal power plants try to add the non-designed low price coal to the fuel. This paper introduces the general situation and actual execution schemes of blending lignitous coal and Indonesia coal in a power plant, studies the influence of different blending schemes on the boiler's efficiency, and makes an analysis on their economic benefits, which can be used as a reference for other similar power plants.

  13. 褐煤与煤直接液化残渣共热解产物半焦性能研究%Properties of semi-coke from co-pyrolysis of lignite and direct liquefaction residue of Shendong coal

    Institute of Scientific and Technical Information of China (English)

    李晓红; 马江山; 薛艳利; 李文英

    2015-01-01

    为使煤直接液化残渣得到清洁高效再利用,采用常压固定床反应器,对神东煤直接液化残渣与呼伦贝尔褐煤共热解制取的半焦进行了研究。结合扫描电镜、N2-吸附、X射线衍射、拉曼光谱以及热重分析发现,共热解过程中存在的软化熔融现象导致液化残渣与褐煤相互黏结,共热解半焦比表面积与孔体积减小,半焦结构有序化程度增加。与褐煤单独热解半焦相比,共热解半焦CO2气化反应性能低。%In order to make use of coal direct liquefaction residue efficiently, co-pyrolysis of Hulunbuir lignite and direct liquefaction residue ( DLR) of Shendong coal were conducted in a fixed bed reactor under atmospheric pressure. The physicochemical properties of co-pyrolysis semi-coke were analyzed by scanning electron microscope, nitrogen adsorption-desorption, X-ray diffraction, Raman spectroscopy and thermogravimetric analyzer. The results show that DLR semi-coke and lignite semi-coke are cohered each other, because the DLR is softened and melted during co-pyrolysis. The specific surface area and pore volume of co-pyrolysis semi-coke decrease. Characterization of both XRD and Raman spectroscopy indicate that the order degree of co-pyrolysis semi-coke increases with the addition of DLR. Compared with the lignite semi-coke, the CO2 gasification reactivity of co-pyrolysis semi-coke decreases.

  14. Development of an on-line coal quality management system in a lignite open pit mine in Serbia

    Energy Technology Data Exchange (ETDEWEB)

    Zimmer, B. [Montan Bildungs-und Entwicklungsgesellschaft mbH, Theiben, (Germany)

    2010-07-01

    This paper presented a study regarding the development of a coal quality management system (CQMS) for two open pit mines located in Serbia called Tamnava West and Veliki Crljeni. The study was based on on-line measurements, and was commissioned by the public energy corporation Elektroprivreda Srbjie. The purpose of the study was to develop a CQMS that met the quality requirements of the power plants by implementing a rigorous exploration, production planning, and production monitoring system in order to control the production according to certain quality parameters. The paper provided general information and described the initial situation. It also presented an analysis of the necessity to introduce a production monitoring and control system. The setup and layout of a production monitoring and control system based on on-line measurements were outlined, with particular reference to the determination of input parameters for every excavator for the tracking of masses; the simulation of mass tracking and summation of the masses at the transfer points towards the major conveyor; and the monitoring of the output and control of the mass flow according to determined limit values. Recommendations for implementation were also discussed. It was concluded that the newly developed CQMS at Tamnava West open pit mine could be classified as uncomplicated with regard to the quality parameters to be controlled, since currently only calorific value was being controlled. 5 refs., 8 figs.

  15. Kinetic analysis on lignite pyrolysis,combustion and gasification

    Institute of Scientific and Technical Information of China (English)

    HU Xin; WANG Zhihua; ZHOU Zhijun; YOU Zhuo; ZHOU Junhu; CEN Kefa

    2013-01-01

    Pyrolysis and combustion combined polygeneration system is a more efficient way for lignite utilization,and can also produce variety of valuable pyrolysis products.To explore the feasibility of this polygeneration system,thermo-gravimetric analysis on YM lignite and DT bituminous coal was conducted,and the characteristic parameters for pyrolysis,combustion,and gasification were obtained.Moreover,the activation energy of each reaction was calculated by Coats-Redfern method.The experimental results showed that,compared with DT bituminous coal,YM lignite pyrolysis process starts at a lower temperature,and its semi-coke reactivity during combustion and gasification was better.In addition,activation energy calculation indicated that,the apparent activation energy of gasification of both coals were much higher than that of the pyrolysis.Therefore,for lignite,pyrolysis and combustion combined polygeneration system may achieve higher efficiency and be worthy for further research.

  16. Evaluation of Kolubara lignite carbon emission characteristics

    Directory of Open Access Journals (Sweden)

    Bakić Vukman V.

    2012-01-01

    Full Text Available The revised Intergovernmental Panel on Climate Change (IPCC guidelines for national greenhouse gas (GHG inventories recommends that more comprehensive and thus more reliable characteristics of the local fossil fuels should be used for the national GHG inventory calculations. This paper deal with the carbon emission characteristics of low-calorific lignite recovered from the Kolubara open-pit mine. The samples of coal were carefully selected in order to cover the net calorific value, ash and water content of the broad spectrum of the quality of the raw lignite supplied to the Serbian thermal power plants. Correlation analysis of the laboratory analysis data gave a linear dependency of the net calorific value on the combustible content in the coal samples. Also, linear correlation between the carbon content and the net calorific value was found. The regression analysis of experimentally determined coal characteristics implies that the carbon emission factor is dependent on the net calorific value. For the subset of raw lignite samples with the net calorific value Qdr = 6 ÷ 10 MJ/kg, that is most representative for current and near future use for power generation in Serbian thermal power plants, the linear dependency CEFr (tC/TJ = 34.407 - 0.5891×Qdr (MJ/kg was proposed. Regarding the net calorific ranges of samples examined, the raw Kolubara lignite carbon emission factor is considerably higher than those recommended by IPCC Tier 1 method of 27.6 tC/TJ.

  17. Regulation of coal polymer degradation by fungi. Fifth quarterly report, July 1995--September 1995

    Energy Technology Data Exchange (ETDEWEB)

    Irvine, R.L.

    1995-10-24

    This research program investigates the solubilization and depolymerization of coal polymer degradation by Fungi. We investigate the hypothesis that solubilization and depolymerization are distinctive events.

  18. Enhanced-hydrogen gas production through underground gasification of lignite

    Institute of Scientific and Technical Information of China (English)

    LIU Shu-qin; WANG Yuan-yuan; ZHAO Ke; YANG Ning

    2009-01-01

    Underground coal gasification is one of the clean technologies of in-situ coal utilization. Hydrogen production from underground gasification of lignite was investigated in this study based on simulation experiments. Pyrolysis of lignite, gasification activity, oxygen-steam gasification and the effect of groundwater influx were studied. As well, the advantages of lignite for stable underground gasification were analyzed. The results indicate that lignite has a high activity for gasification. Coal pyrolysis is an important source of hydrogen emission. Under special heating conditions, hydrogen is released from coal seams at temperatures above 350 ℃ and reaches its maximum value between 725 and 825 ℃. Gas with a hydrogen concentration of 40% to 50% can be continuously obtained by oxygen-steam injection at an optimum ratio of steam to oxygen, while lignite properties will ensure stable gasification. Groundwater influx can be utilized for hydrogen preparation under certain geological conditions through pressure control. Therefore, enhanced-hydrogen gas production through underground gasification of lignite has experimentally been proved.

  19. JV Task 98 - Controlling Mercury Emissions for Utilities Firing Lignites from North America

    Energy Technology Data Exchange (ETDEWEB)

    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.

  20. Evolution of Çan-Etili (Çanakkale-NW Turkey) lignite basin:Sedimentology, petrology, palynology and lignite characterization

    Institute of Scientific and Technical Information of China (English)

    Mustafa Bozcu; Funda Akgün; Gülbin Gürdal; Ayşe Bozcu; Sevinç Kapan Yeşilyurt; Öznur Karaca; M. Serkan Akkiraz

    2015-01-01

    abstract This study examines the development and sedimentology of Çan-Etili lignite basin in Biga Peninsula (NW Turkey) along with the palynologic and petrographic properties of the coals in this region. The Çan-Etili lignite basin discordantly overlies Oligocene-aged Çan volcanics. The basin consists of caldera type sedimentation developed by the combined effects of volcanism and tectonics. The volcanic rocks forming the basement of the basin consist of andesitic, dacitic and basaltic lava flows as well as agglomerates, tuff and silicified tuffs, and kaolin which is their alteration product. The basement volcanic rocks cooled from high potassium and calc-alkaline magma. The trace element geochemistry of different rocks within the volcanics reveals that they are from a volcanic arc. The Çan Formation contains lignites and consists of 6 lithofacies representing alluvial, fluvial, marsh and lacustrine environments. These lithofacies are the lower volcanogenic conglomerate, the claystone, the lignite, the laminated organic claystone, the tuff intercalated sandstone–siltstone and the upper volcanogenic conglomerate. The lignite in the basin is limnic and is formed in a non-fluvial marsh and marsh-lake environment. An abundant percentage of vegetation (Engelhardia, Sapotaceae, Cyrillaceae) is compatible with temperate and subtropical climatic conditions in the basin during sedimentation of lignite.The coals of Çan-Etili basin are humic with high sulfur content (6–6.5%average) mostly containing huminite compounds belonging to the class of lignite-low bituminous (C-A) coal. Their coalification rank is between 0.38%and 0.56%Ro. The coals are formed in limnic-limnotelmatic marsh zones based on their microlithotype components. The inorganic components of the coal mostly consist of pyrite and clay. The trace elements, As, Th, U and V, are higher than international coal standards. The coal quality is adversely affected by high sulfur content and sulfur driven trace

  1. Analysis of low temperature coal tar in Inner Mongolia lignite briquette by GC-MS.%GC-MS在内蒙褐煤型煤块低温煤焦油成分分析中的应用

    Institute of Scientific and Technical Information of China (English)

    李香兰; 崔新涛; 张永发

    2012-01-01

    采用蒸馏技术和GC-MS技术,对内蒙褐煤型煤块低温炭化产品低温煤焦油馏分进行了定性定量分析,分析结果表明:内蒙褐煤型煤块的低温煤焦油中≤340℃的馏分占焦油重量的82.88%;>340℃的为沥青,占焦油重量的17.02%.从≤340℃的馏分中定性定量出139种化合物,其中,烃类占焦油的34.38%,以脂肪族烷烃为主,烯烃、环烷烃占少量;酚类占焦油的12.01%,集中在210℃前的馏分;芳烃类占焦油的16.73%,以甲基、乙基、丙基丁基等多烷基苯的取代衍生物为主,分布在各个馏分中,萘和甲基萘的衍生物以及蒽、菲芳烃主要集中在300℃前得馏分;含氧和含氮及杂环化合物分别占焦油的4.61%,0.52%,2.23%.通过研究为褐煤低温焦油的深加工利用提供了基础数据,同时提供了分析褐煤型煤块干馏产生的低温焦油的方法.%Distillation and GC-MS were employed to analysis the coal tar of low-temperature pyrolysis of Inner Mongolia lignite briquette by contrasting with standards, the results showed that the fraction below 340 C in the tar distillates of low temperature brown coal tar accounted for 82. 88% (weight percent) and the other greater than 340'C is pitch accounted for 17. 02%. 139 kinds of compounds were analyzed by qualitative and quantitative methods from the fraction below 340'C. 34. 38% of coal tar are hydrocarbons which are mainly consisted of fat aliphatic hydrocarbon and include few alkene and cycloparaffins. The content of phenolic compounds in coal tar, mainly comes from the fraction below 210"C , is 12. 01%. 16. 73% of coal tar is aromatic compounds which are mainly composed of substitutive derivative of polyalkylbenzene (methyl, ethyl, propyl and butyl etc. ) distributing in all kinds of fractions; and a small amount of aromatic compounds include anthracene, phenanthrene, naphthalene and substitutive derivative of methyl-naphthalene which concentrate in the fraction

  2. ACTIVATED CARBON FROM LIGNITE FOR WATER TREATMENT

    Energy Technology Data Exchange (ETDEWEB)

    Edwin S. Olson; Daniel J. Stepan

    2000-07-01

    High concentrations of humate in surface water result in the formation of excess amounts of chlorinated byproducts during disinfection treatment. These precursors can be removed in water treatment prior to disinfection using powdered activated carbon. In the interest of developing a more cost-effective method for removal of humates in surface water, a comparison of the activities of carbons prepared from North Dakota lignites with those of commercial carbons was conducted. Previous studies indicated that a commercial carbon prepared from Texas lignite (Darco HDB) was superior to those prepared from bituminous coals for water treatment. That the high alkali content of North Dakota lignites would result in favorable adsorptive properties for the very large humate molecules was hypothesized, owing to the formation of larger pores during activation. Since no standard humate test has been previously developed, initial adsorption testing was performed using smaller dye molecules with various types of ionic character. With the cationic dye, methylene blue, a carbon prepared from a high-sodium lignite (HSKRC) adsorbed more dye than the Darco HDB. The carbon from the low-sodium lignite was much inferior. With another cationic dye, malachite green, the Darco HDB was slightly better. With anionic dyes, methyl red and azocarmine-B, the results for the HSKRC and Darco HDB were comparable. A humate test was developed using Aldrich humic acid. The HSKRC and the Darco HDB gave equally high adsorption capacities for the humate (138 mg/g), consistent with the similarities observed in earlier tests. A carbon prepared from a high-sodium lignite from a different mine showed an outstanding improvement (201 mg/g). The carbons prepared from the low-sodium lignites from both mines showed poor adsorption capacities for humate. Adsorption isotherms were performed for the set of activated carbons in the humate system. These exhibited a complex behavior interpreted as resulting from two types

  3. Sulfur removal from Gediz lignite using aqueous sodium hydroxide solutions under mild oxidative conditions

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Kuecuekbayrak, S. [Istanbul Technical Univ. (Turkey). Chemical and Metallurgical Engineering Faculty

    1999-11-01

    Sulfur removal from a high-sulfur Turkish lignite (Gediz) using aqueous sodium hydroxide solutions having dissolved oxygen was investigated under mild oxidative conditions. Effects of the parameters such as sodium hydroxide/lignite weight ratio, temperature, and partial pressure of oxygen were investigated within the ranges of 0.05--0.8, 423--498 K, and 1--2 MPa, respectively. Optimum values of these parameters were determined regarding sulfur removal and coal recovery. Influences of dry oxidation of the lignite sample as a pretreatment at 573 K and subsequent washing of some treated lignite samples with 1 N HCl were investigated.

  4. Lignite chemical conversion in an indirect heat rotary kiln gasifier

    Directory of Open Access Journals (Sweden)

    Hatzilyberis Kostas S.

    2006-01-01

    Full Text Available The results on the gasification of Greek lignite using two indirect heat (allothermal pilot rotary kiln gasifiers are reported in the present work. The development of this new reactor-gasifier concept intended for solid fuels chemical conversion exploits data and experience gained from the following two pilot plants. The first unit A (about 100 kg/h raw lignite demonstrated the production of a medium heating value gas (12-13 MJ/Nm3 with quite high DAF (dry ash free coal conversions, in an indirect heat rotary gasifier under mild temperature and pressure conditions. The second unit B is a small pilot size unit (about 10 kg/h raw lignite comprises an electrically heated rotary kiln, is an operation flexible and exhibits effective phase mixing and enhanced heat transfer characteristics. Greek lignite pyrolysis and gasification data were produced from experiments performed with pilot plant B and the results are compared with those of a theoretical model. The model assumes a scheme of three consecutive-partly parallel processes (i. e. drying, pyrolysis, and gasification and predicts DAF lignite conversion and gas composition in relatively good agreement with the pertinent experimental data typical of the rotary kiln gasifier performance. Pilot plant B is currently being employed in lime-enhanced gasification studies aiming at the production of hydrogen enriched synthesis gas. Presented herein are two typical gas compositions obtain from lignite gasification runs in the presence or not of lime. .

  5. 神府煤和锡林浩特煤的非均相光催化氧化%Photo-catalytic oxidation of Shenfu coal and Xilinhot lignite in heterogeneous hydration system

    Institute of Scientific and Technical Information of China (English)

    解恒参; 宗志敏; 刘彤; 魏晴; 赵建军; 赵培芝; 魏贤勇

    2011-01-01

    采用悬浮式非均相体系分别对水合神府烟煤(SFC)及锡林浩特褐煤(XL)进行选择性光催化氧化、傅里叶红外光谱(FTIR)分析及气相色谱质谱联用(GS/MS)检测,获得了反应产物的分子结构信息.同时对不同条件下煤炭降解效果的研究发现:芳香度和芳环取代度较高的烟煤组分光氧化性较弱,氧化后的产物中有较多酮类生成,而芳环取代度小、含有较多亚甲基和脂肪族侧链的褐煤光氧化性能较强,生成物中烯烃的含量明显减少;催化剂二氧化钛对光催化反应的影响要大于氧化剂过氧化氢,但在仅有过氧化氢存在情况下,随着其加入量的增大光氧化效果会更显著,煤样的投加量对光催化的影响不占主导地位;光催化氧化中,煤大分子中的烷基侧链易断裂脱除,特别是甲基和亚甲基易发生光催化氧化分解,而且碳氧单键的红外吸收峰强度明显减弱,表明煤大分子的侧链和碳氧单键在紫外光辐射环境下反应活性高.%Shenfu bituminous coal (SFC) and Xilinhot lignite (XL) were oxidized selectively using hydrogen peroxide in heterogeneous hydration suspension system and analyzed with FTIR and GC/MS technologies, meanwhile the oxidation effect of different conditions were also discussed. The results indicate that the photo-catalytic oxidation activity of the bituminous coal with high aromaticity correlation and alkyl substitutions on aromatic fractions is lower than that of Xilinhot lignite with lower alkyl substitutions on aromatic fractions and large of mehtyl and methylene. In the products a number of organic ketones are enough besides biphenyls in SFC, but the relative content of the alkenes is reduced obviously in XL. And the effect factors are in the order amount of photocatalyst>dosage of H2 O2 >amount of coal. However with the increasing of H202 dosage the oxidation of coals is much more significant. In the experiment the organic maters with branched

  6. Adsorption of an anionic dispersant on lignite

    Energy Technology Data Exchange (ETDEWEB)

    Yavuz, R.; Kucukbayrak, S. [Istanbul Technical University, Istanbul (Turkey). Dept. of Chemical Engineering, Chemical & Metallurgical Engineering Faculty

    2001-12-01

    Since coal is not a homogeneous substance but a mixture of carbonaceous materials and mineral matter, it has a variety of surface properties. Therefore, it is not easy to control the properties of coal suspensions by simply adjusting variables, such as pH and/or electrolyte. A chemical agent needs to be added to control the properties of the coal suspensions. The adsorption behavior of an anionic dispersant in the presence of a wetting agent using some Turkish lignite samples was investigated. The effects of dispersant concentration, temperature and pH on the dispersant adsorption were studied systematically, and the experimental results are presented. Pellupur B69 as a dispersant, commercial mixture of formaldehyde condensate sodium salt of naphthalene sulphonic acid, and Texapon N{sub 2}5 as a wetting agent, a sodium lauryl ether sulfate, have been used.

  7. Solvent refined lignite process development. Quarterly technical progress report No. 3, January--March 1978

    Energy Technology Data Exchange (ETDEWEB)

    Severson, D.E.

    1978-07-12

    Six runs, each nominally at one week's duration, M-34 through M-39, were completed; this concludes the PDU experimental program for Project Lignite. The first three runs concluded the series to study the effects of different lignites on plant operability and product yields. Runs M-37 and M-38 were made using two Montana subbituminous coals. It was concluded that coals with the highest ash content, both lignite and subbituminous coals, gave greater overall conversion to gaseous and liquid organic products. The subbituminous coals gave lower gas yields and lower overall conversion while producing similar liquid yields when compared with lignite. Reactor solids build up rapidly during initial operations, then level off and remain constant at 29 pounds per cubic foot of reactor volume as a run proceeds. Reactor solids evidently are composed of clay minerals and large particles of pyridine insoluble organic material when processing either lignites or subbituminous coals; in addition calcium/magnesium carbonate crystals (calcite/dolomite) are present in the case of lignite. Long term, trouble-free operation of the deashing unit was not accomplished. Integration of the unit for several hours of combined operation of the process was achieved, and the product from the deashing unit contained as low as 0.6% ash and pyridine insoluble material. Solids buildup in the solids settling tower was a continuing problem.

  8. Low-temperature ashing of Bulgarian lignites

    Energy Technology Data Exchange (ETDEWEB)

    Douchanov, D.; Minkova, V.; Martinez-Alonso, A.; Palacios, J.M.; Tascon, J.M.D. [Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. of Organic Chemistry

    1993-12-01

    The characterization of mineral components of coals requires their isolation from organic matter, which would otherwise interfere with phase identification by means of physico-chemical techniques. Low-temperature ashing (LTA) using a cool oxygen plasma is a prospective method to oxidise coal organic matter at low temperatures while keeping the mineral constituents unaltered. In this work the authors used a microwave-excited plasma apparatus for the LTA treatment of lignite samples from the Maritza-Iztok (M-1-1; M-1-2) and Elhovo basins. Minerals were characterised in the LTA residues using FT-IR spectroscopy, X-ray diffraction and scanning electron microscopy combined with energy-dispersive X-ray microanalysis. The advantages and disadvantages of the LTA method are discussed. Results indicate that LTA performs well for the isolation of mineral matter, the ensuing methodology being adequate for the characterisation of Bulgarian lignites. The same mineral constituents (principally clay minerals, quartz, pyrite and carbonates) were identified in all the three studied samples, differences being mainly in their particle size, degree of crystallinity and distribution in the organic matter of coals. 43 refs., 5 figs., 3 tabs.

  9. What are cleats? Preliminary studies from the Konin lignite mine, Miocene of central Poland

    Science.gov (United States)

    Widera, Marek

    2014-03-01

    Cleats (fractures, joints) are discontinuities in coals, including lignites. They are important in mining activity because of their gas and water permeability in hard coal, and mainly because of their water permeability in lignites. As opposed to hard-coal cleats, lignite cleats have not been studied in detail before. The present contribution does so, using as an example the 1st Middle-Polish Lignite Seam (MPLS-1) in the Jóźwin IIB opencast mine in central Poland. It should be mentioned here that any remarks in the present contribution concerning MPLS-1 refer exclusively to this lignite seam in the Jóźwin IIB opencast mine. The investigated discontinuities consist of two sets, i.e. the face and butt cleats, which are roughly oriented NW-SE and NE-SW, respectively. The mean spacing of the face cleats is ~12.4 cm, while the mean spacing of the butt cleats is ~12.8 cm. The maximum average aperture is ~4.9 mm for the face cleats and ~4.1 mm for the butt cleats. The cleat spacing and aperture do not depend on the lignite thickness, but the cleat spacing increases with increasing mineral-matter and xylite content, whereas the aperture increases when the contents decrease. The regional folding and local salt diapirism tentatively explain the formation of the orthogonal system of the lignite cleats, partly because of the parallelism of the face cleats and the major tectonic directions in central Poland.

  10. Comparative study of peat and lignite on the basis of proximate and ultimate analysis

    Energy Technology Data Exchange (ETDEWEB)

    Schelkoph, G.M.; Malterer, T.J.; Steadman, E.N.

    1985-01-01

    Ultimate and proximate analytical data was used as the basis for comparisons of selected United States peats and North Dakota lignites that have formed under a variety of depositional environments, in order to better understand the transitional relationships involved in the transformation of peat to lignite. A ternary diagram of the bond-equivalents of C, O, and H can be used to represent relationships among complex chemical compounds. This method was initially developed for Australian brown coals. The rationale for adopting this method was the usefulness of the reaction trajectories in identifying the dominating chemical changes in coalification. The mass percentage of nitrogen and organic sulfur are added to the mass percentage of oxygen. The bond equivalence data implies that a relationship exists between peat and lignite by the cellulose present and the degree of decarboxylation. It has been shown elsewhere that the carboxyl content of Minnesota peat and Yalloun brown coal are greater than that of a North Dakota lignite. Collateral research at UNDERC has found virtually no cellulose in North Dakota lignite, but 5% cellulose (maf) in Minnesota peat. This relationship implies that decellulosation and decarboxylation reactions represented on the ternary diagram are occurring in the diagenesis of peat to lignite. The data further indicates that Australian brown coals are indeed intermediate in coalification between United States peat and North Dakota lignite.

  11. Co - pyrolysis of biomass and Polish lignite

    Energy Technology Data Exchange (ETDEWEB)

    Kordylewski, Wlodzimierz; Stojanowska, Grazyna [Politechnika Wroclawska, Wroclaw (Poland); Jones, Jenny [Univ. of Leeds (United Kingdom). Energy and Resources Research Inst.

    2006-01-15

    The paper presents results of studies of the chemical decomposition of coal, biomass and their blends during low rate heating gasification in atmosphere of air or nitrogen. Polish lignite (Turow), sawdust of pine and blends of these two fuels have been used in the research and it has been investigated the influence of ion exchanged calcium on their pyrolysis. The primary products of devolatilization provided important information for understanding subsequently the leading to toxic organic compounds and synergistic effects of these fuels. The influence of blending ratio and influence of calcium catalysts was discussed.

  12. The increase in lignite production in Southern India

    Energy Technology Data Exchange (ETDEWEB)

    Consejo Superior de Colegios de Ingenieros de Minas

    The first bucket-wheel excavator with a capacity of 50,000 cu.m per day, has just been brought into service at the Neyveli opencast lignite workings, in the state of Tamil- Nadu, Southern India. It is expected that with this machine, annual lignite production will be increased from a figure of 3.5 million to a figure of 6.5 million tons. This increase in production is a significant one in terms of meeting India's energy requirements, since of the 90% of India's commerciably workable coal reserves, some 20,000 m tons are located in the Neyveli area. (In Spanish)

  13. Synergies in co-pyrolysis of Thai lignite and corncob

    Energy Technology Data Exchange (ETDEWEB)

    Sonobe, Taro [The Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, 126 Pracha-Uthit Road, Bangmod, Tungkru, Bangkok, 10140 (Thailand); Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Worasuwannarak, Nakorn; Pipatmanomai, Suneerat [The Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, 126 Pracha-Uthit Road, Bangmod, Tungkru, Bangkok, 10140 (Thailand)

    2008-12-15

    The results from TGA experiments at the temperature range of 300-600 C evidently distinguished the different pyrolysis behaviours of lignite and corncob; however, no clear synergistic effects could be observed for the mixture. The investigation of co-pyrolysis in a fixed-bed reactor, however, found significant synergies in both pyrolysis product yields and gas product compositions. The solid yield of the 50:50 lignite/corncob blend was much lower (i.e. 9%) than expected from the calculated value based on individual materials under the range of temperatures studied, and coincided with the higher liquid and gas yield. The synergistic effect in product gas composition was highly pronouncing for CH{sub 4} formation, i.e. three times higher than the calculated value at 400 C. Possible mechanisms were described including the interaction between corncob volatiles and lignite particles, and the effect of the heat profiles of lignite and corncob pyrolysis on the temperature dependent reactions. The enhanced devolatilisation of the blend was explained by the transfer of hydrogen from biomass to coal as well as the promotion of low-temperature thermal decomposition of lignite by exothermic heat released from corncob pyrolysis. Moreover, water, which was one of the major components in corncob volatiles produced mainly at around 200-375 C, can also be expected to act as a reactive agent to promote the secondary tar cracking producing more CH{sub 4}. (author)

  14. Nonisothermal Thermogravimetric Analysis of Thai Lignite with High CaO Content

    Directory of Open Access Journals (Sweden)

    Pakamon Pintana

    2013-01-01

    Full Text Available Thermal behaviors and combustion kinetics of Thai lignite with different SO3-free CaO contents were investigated. Nonisothermal thermogravimetric method was carried out under oxygen environment at heating rates of 10, 30, and 50°C min−1 from ambient up to 1300°C. Flynn-Wall-Ozawa (FWO and Kissinger-Akahira-Sunose (KAS methods were adopted to estimate the apparent activation energy (E for the thermal decomposition of these coals. Different thermal degradation behaviors were observed in lignites with low (14% and high (42% CaO content. Activation energy of the lignite combustion was found to vary with the conversion fraction. In comparison with the KAS method, higher E values were obtained by the FWO method for all conversions considered. High CaO lignite was observed to have higher activation energy than the low CaO coal.

  15. Coal facies studies in Greece

    Energy Technology Data Exchange (ETDEWEB)

    Christanis, Kimon [Department of Geology, University of Patras, GR-265.00 Rio-Patras (Greece)

    2004-04-23

    In Greece, coal-forming conditions prevailed mainly during Neogene and Quaternary times in several intermontane and paralic basins and resulted in the formation of significant peat and lignite deposits. The economically recoverable lignite reserves are 3.9 Gt and the annual production, mainly for power generation, exceeds 65 Mt.

  16. Changes in coal structure accompanying the formation of regenerated humic acids during air oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Calemma, V.; Iwanski, P.; Rausa, R.; Girardi, E. (Eniricerche S.p.A., Milan (Italy))

    1994-05-01

    Dry-phase oxidation of two subbituminous coals and a lignite was carried out in a fluidized bed reactor at 200[degree]C, at different oxygen partial pressures and reaction times up to 4 h. The formation and evolution of various oxygenated functional groups (ester, carboxyl, ketone and hydroxyl) was investigated by FT-i.r. spectroscopy using a curve-resolving procedure and acetylation of coal samples. The development of alkali solubility of the coal as a function of reaction time was studied and the average molecular weight of regenerated humic acids (RHA) extracted from the oxidized coal was determined. The lower molecular weight of RHA extracted from highly oxidized coal samples suggests that besides the build-up of various oxygenated functional groups, the development of alkali solubility also results from concomitant 'depolymerization' of the coal network. The latter may occur through oxidation of aliphatic cross-links and formation of ester groups hydrolysable in basic solution. The FT-i.r. results were correlated with the development of alkali solubility. Some oxidation pathways are proposed. 49 refs., 11 figs., 1 tab.

  17. Oxydesulfurization of a Turkish lignite using trona solutions

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Kuecuekbayrak, S. [Istanbul Technical Univ. (Turkey). Chemical and Metallurgical Engineering Faculty

    1996-06-01

    This article investigates the possibility of using trona minerals in the oxydesulfurization of coal. The experiments were performed on a Turkish lignite having high organic and high pyritic sulfur content from the Gediz area. Oxydesulfurization of the lignite sample using trona minerals was studied at 423--473 K, under 0--1 MPa oxygen partial pressure at 0--0.3 M equivalent alkalinity of Na{sub 2}CO{sub 3} for 2.5--60 min. Almost all of the pyritic sulfur content and, depending on the working conditions, an important part of the organic sulfur content were removed. Unless the temperature reached 473 K, solid product yield was not negatively affected. Trona minerals were seen as a suitable alkaline to use in oxydesulfurization of coal.

  18. Solubilisation of lignite during oxydesulphurization in alkaline solutions

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Kuecuekbayrak, S. [Istanbul Technical Univ., Chemical Engineering Dept. (Turkey)

    1997-12-31

    Some desulphurization processes such as oxydesulphurization in which dissolved oxygen is attached to coal particles are performed usually in alkaline solutions. Therefore, these processes are resulted in not only sulphur removal but also some solubilisation of the coal matrix. In this study three different Turkish lignite samples are subjected to various oxydesulphurization processes in which dilute solutions of NaOH, Na{sub 2}CO{sub 3}, NH{sub 4}OH or Na{sub 2}B{sub 4}O{sub 7} containing dissolved oxygen under pressure were applied. The experiments were performed in a magnetically stirred and electrically heated Parr autoclave. The extent of the solubilisation is varied depending on the type and concentration of the alkaline used, the applied temperature and the rank of the lignite sample used. (orig.)

  19. Sulfur removal from lignite by oxydesulfurization using fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Kucukbayrak, S. [Istanbul Technical University, Istanbul (Turkey). Chemical Engineering Dept.

    1997-01-01

    Since fly ash contains alkaline oxides, it is possible to use its water-extractable components as a desulfurization agent. This was investigated using some high-sulfur Turkish lignites. The effects of the amount of fly ash used, temperature, partial pressure of oxygen and time were studied in the range 5-40 g, 403-498 K, 0.0-1.5 MPa and 15-90 min respectively. The extents of pyritic and organic sulfur removal and recoveries of coal and calorific value were investigated for each of these variables. Reactivity and some combustion characteristics (ignition temperature, end temperature of combustion and combustion rate) of original and desulfurzed lignite samples were compared using combustion curves obtained from thermogravimetric analysis (t.g.a) results. FT-i.r. spectroscopy was used to determine the effects of the desulfurization process on the coal structure. 5 refs., 6 figs.,4 tabs.

  20. Investigation of pre-drying lignite in an existing Greek power plant

    Directory of Open Access Journals (Sweden)

    Agraniotis Michalis

    2012-01-01

    Full Text Available The application of lignite pre-drying technologies in next generation of lignite power plants by utilizing low pressure steam as a drying medium instead of hot recirculated flue gas - combined with thermal utilization of the vaporized coal moisture - is expected to bring efficiency increase of 2-4 percentage points in future lignite power plants compared with today’s state of the art. The pre-drying concept is of particular importance in Greek boilers firing lignite with a high water and ash content. The combustion of Greek predried lignite has been investigated experimentally and via numerical simulations in our previous research. This study focuses on the potential integration of a lignite pre-drying system in an existing Greek power plant with dry lignite co-firing thermal share of up to 30%. The radiative and convective heat fluxes to the boiler and the overall boiler heat balance is calculated for reference and dry lignite co-firing conditions by an in-house calculation code. The overall plant’s thermal cycle is then simulated using commercial thermal cycle calculation software. The net plant efficiency is in this way determined for reference and dry coal co-firing conditions. According to the simulation results the integration of a pre-drying system and the implementation of dry lignite co-firing may bring an efficiency increase of about 1.5 percentage points in existing Greek boilers. It is therefore considered as an important measure towards improving plant efficiency and reducing specific CO2 emissions in existing plants.

  1. Proximate analysis of some Turkish lignites by thermogravimetry

    Energy Technology Data Exchange (ETDEWEB)

    Karatepe, N.; Kucukbayrak, S. (Istanbul Technical University, Istanbul (Turkey). Faculty of Chemistry and Meteorological Engineering)

    1993-01-14

    In this study, the moisture, ash, volatile matter and fixed carbon contents of 24 lignite samples from different coal reserves in Turkey were determined by using TGA and results were compared with those obtained by the ASTM standards. The mean differences in moisture, ash, volatile matter and fixed carbon contents between the TGA and ASTM methods are 0.38%, 0.68%, 1.53% and 1.47%, respectively.

  2. Optimize to pulverizing system control method for the Indonesian high moisture lignite coal%针对印尼高水分褐煤的制粉系统优化控制方法

    Institute of Scientific and Technical Information of China (English)

    程学安

    2012-01-01

      This paper introduces the main problem of the lignite pulverizing system of large power stations, the use of actual production experience in Indonesia, for high-moisture lignite explosive the drying capacity demand large, the optimal control method. Domestic medium-speed mill boilers fueled with high moisture lignite certain reference.%  该文介绍了现有燃用褐煤的大型电站的制粉系统出现的主要问题,并利用在印尼实际的生产经验,针对高水分褐煤易爆炸,干燥出力需求大等特点,提出了相应的优化控制方法。对国内中速磨锅炉燃用高水分褐煤有一定的借鉴作用。

  3. Depolymerization of sulfated polysaccharides under hydrothermal conditions.

    Science.gov (United States)

    Morimoto, Minoru; Takatori, Masaki; Hayashi, Tetsuya; Mori, Daiki; Takashima, Osamu; Yoshida, Shinichi; Sato, Kimihiko; Kawamoto, Hitoshi; Tamura, Jun-ichi; Izawa, Hironori; Ifuku, Shinsuke; Saimoto, Hiroyuki

    2014-01-30

    Fucoidan and chondroitin sulfate, which are well known sulfated polysaccharides, were depolymerized under hydrothermal conditions (120-180°C, 5-60min) as a method for the preparation of sulfated polysaccharides with controlled molecular weights. Fucoidan was easily depolymerized, and the change of the molecular weight values depended on the reaction temperature and time. The degree of sulfation and IR spectra of the depolymerized fucoidan did not change compared with those of untreated fucoidan at reaction temperatures below 140°C. However, fucoidan was partially degraded during depolymerization above 160°C. Nearly the same depolymerization was observed for chondroitin sulfate. These results indicate that hydrothermal treatment is applicable for the depolymerization of sulfated polysaccharides, and that low molecular weight products without desulfation and deformation of the initial glycan structures can be obtained under mild hydrothermal conditions.

  4. Biotransformation of Spanish coals by microorganisms; Biotransformacion de Carbones Espanoles por Microorganismos

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    some newly isolated microorganisms could solubilized different kinds of Spanish coals (hard coal, subbituminous coal and lignite). Certain fungi and bacteria could solubilized lignite when growing in a mineral medium. However, to solubilized higher rank coals (hard coal and subbituminous coal) microorganisms require a complete medium. Microorganisms, which showed higher capacity to solubilized coal, were incubated in the presence of coal (hard coal, subbituminous coal and lignite) at the optimal conditions to get coal liquefaction/solubilization. The resultant products were analysed by IR and UV/visible spectrometry. No major differences among the original coal, solubilized/liquefied coal and residual coal were detected. However, an increase in metallic carboxylate and a decrease in OH'- carboxylic groups were observed in the liquefied lignite. Humic acids derived from original lignite residual lignite and liquefied/solubilized lignite by microorganisms were analysed. Several differences were observed in the humic acids extracted from the liquefied lignite, such as an increase in the total acidity and in the proportion of the phenolic groups. Differences on the humic acid molecular weight were observed too. Several fungal and bacterial strains were able to grow using humic acids as sole carbon source. Microorganisms growing in humic acid were observed by Scanning Electron Microscopy. Besides, the coal solubilization capacity of several fungal strains (M2, m$ and AGI) growing in different culture media was assayed. In order to get some insight into the mechanisms of the liquefaction/solubilization of Spanish coals (hard coal, subbituminous coal and lignite) by these microorganisms, some features in the culture supernatants were studied: pH values; extracellular specific proteins; enzyme activities possibly related with coal solubilization and the presence of oxalate. M2 and M4 fungal strains grown in the presence of coal produced some specific extracellular

  5. Advanced power assessment for Czech lignite. Task 3.6, Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Sondreal, E.A.; Mann, M.D.; Weber, G.W.; Young, B.C.

    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 a 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.

  6. Petrographic composition of lignite from the Szczerców deposit, Polish Lowlands

    Science.gov (United States)

    Pawelec, Sandra; Bielowicz, Barbara

    2016-12-01

    Macroscopic and microscopic composition of lignite from the Szczerców deposit belonging to the Bełchatów Lignite Mine (Polish Lowlands) has been examined. The macroscopic composition was determined according to the newest lithological classification of humic coal. On this basis, it has been shown that the main lithotypes occurring in the Szczerców deposit are the detritic and xylodetritic lignites. The petrographic composition of the investigated lignite was determined microscopically for 11 samples. The examined lignite is predominantly composed of macerals from the huminite group. It is in the range from 75.2 to 86%, including atrinite (23.1-40.7%, averaging 28.9%) and densinite (18.2-41.4 %, averaging 24.9%). It also demonstrated that the statistical variability of the macerals content from the huminite group in the studied lignite is very weak in all samples. In addition, the random reflectance of ulminite was measured traditionally. The results, ranging from 0.247 to 0.282%, with the maximum permissible standard deviation < 0.07, were achieved for all analysed lignite samples.

  7. Study on the comparison of the pyrolysis gas release of lignite and its briquette

    Institute of Scientific and Technical Information of China (English)

    ZHU Shi-feng; CHU Mo; ZHAO Fei-xiang

    2012-01-01

    In this experiment,lignite was refined and processed through binderless briquette preparation process from low-rank coal and became briquette.Then,lignite and its briquette were pyrolysed as materials to compare the nature of their pyrolysis.In this study,the experiment was carried out through a lab tube furnace,at a heating rate of 10 ℃/min,and the gas was analyzed and compared,which was collected at different temperatures.The results show that:in the pyrolysis temperature of 550~850 ℃,the semi-coke yield of briquette is 2%~6% higher than lignite,the tar yield of briquette is 2%~3% higher than lignite and the gas yield of briquette is 4%~9% less than lignite.The time required for complete release of the briquette is about 20 min less than lignite.The components in the pyrolysis gas of lignite and its briquette are the same,and their variation with the pyrolysis temperature is similar.

  8. Redox Catalysis Facilitates Lignin Depolymerization.

    Science.gov (United States)

    Bosque, Irene; Magallanes, Gabriel; Rigoulet, Mathilde; Kärkäs, Markus D; Stephenson, Corey R J

    2017-06-28

    Lignin is a recalcitrant and underexploited natural feedstock for aromatic commodity chemicals, and its degradation generally requires the use of high temperatures and harsh reaction conditions. Herein we present an ambient temperature one-pot process for the controlled oxidation and depolymerization of this potent resource. Harnessing the potential of electrocatalytic oxidation in conjugation with our photocatalytic cleavage methodology, we have developed an operationally simple procedure for selective fragmentation of β-O-4 bonds with excellent mass recovery, which provides a unique opportunity to expand the existing lignin usage from energy source to commodity chemicals and synthetic building block source.

  9. Cheap carbon sorbents produced from lignite by catalytic pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, B.N.; Schchipko, M.L. [Inst. of Chemistry of Natural Organic Materials, Akademgorodok, Krasnoyarsk (Russian Federation)

    1995-12-01

    Some data are presented describing the new technology of carbon sorbent production from powdered lignite in the installation with fluidized bed of catalyst. It was shown the different types of char products with extended pore structure and high sorption ability can be produced from cheap and accessible lignite of Kansk-Achinsk coal pit in pilot installation with fluidized bed of Al-Cu-Cr oxide catalyst or catalytically active slag materials. In comparison with the conventional technologies of pyrolysis the catalytic pyrolysis allows to increase by 3-5 times the process productivity and to decrease significantly the formation of harmful compounds. The latter is accomplished by complete oxidation of gaseous pyrolysis products in the presence of catalysts and by avoiding the formation of pyrolysis tars - the source of cancerogenic compounds. The technology of cheap powdered sorbent production from lignites makes possible to obtain from lignite during the time of pyrolysis only a few seconds char products with porosity up to 0.6 cm{sup 3} /g, and specific surface area more than 400 m{sup 3} /g. Some methods of powdered chars molding into carbon materials with the different shape were proved for producing of firmness sorbents. Cheap carbon sorbents obtained by thermocatalytic pyrolysis can be successfully used in purification of different industrial pollutants as one-time sorbent or as adsorbents of long-term application with periodic regeneration.

  10. Crowding of molecular motors determines microtubule depolymerization

    CERN Document Server

    Reese, Louis; Frey, Erwin

    2011-01-01

    Assembly and disassembly dynamics of microtubules (MTs) is tightly controlled by MT associated proteins. Here, we investigate how plus-end-directed depolymerases of the kinesin-8 family regulate MT depolymerization dynamics. Employing an individual-based model, we reproduce experimental findings. Moreover, crowding is identified as the key regulatory mechanism of depolymerization dynamics. Our analysis gives two qualitatively distinct regimes. For motor densities above a particular threshold, a macroscopic traffic jam emerges at the plus-end and the MT dynamics become independent of the motor concentration. Below this threshold, microscopic traffic jams at the tip arise which cancel out the effect of the depolymerization kinetics such that the depolymerization speed is solely determined by the motor density. Because this density changes over the MT length, length-dependent regulation is possible. Remarkably, motor cooperativity does not affect the depolymerization speed but only the end-residence time of depo...

  11. Structure of some western Anatolia coals investigated by FTIR, Raman, C-13 solid state NMR spectroscopy and X-ray diffraction

    OpenAIRE

    Baysal, Mustafa; Yürüm, Alp; Yurum, Alp; Yıldız, Burçin; Yildiz, Burcin; YÜRÜM, YUDA; Yurum, Yuda

    2016-01-01

    Turkey has one of the largest lignite deposits in Europe but the low calorific values of Turkish lignites dictate new and environmentally safe new utilization technologies for further utilization. Research on coal chemical structures has long been of great interest as a fundamental issue for coal chemistry. Identifying the structures of organic material in lignites is important for lignite conversions to clean liquid fuels and value-added chemicals. Therefore, investigation of chemical and de...

  12. Microscopical investigation of the transformation (diagenesis) from peat to lignite

    Energy Technology Data Exchange (ETDEWEB)

    Ting, F.T.C.

    1977-01-01

    A silicified Palaeocene peat layer discovered in a lignite bed in western North Dakota, U.S.A., has proved to be excellent material for studying the transformation from peat to lignite. Detailed anatomical structures are well preserved in the peat and similar to the level of preservation of Carboniferous coal balls. A compaction of 4:1 results when the peat is converted to lignite. Loss in volume is primarily caused by the loss of cellular cavities and intergranular spaces and consequent loss of redistribution of moisture. Huminite formed from secondary xylem and phloem sclereids differs in appearance under the microscope from huminite derived from periderms and young cortical tissues. Resinites are formed from fillings of resin canals, secretory cells and sclereids of secondary phloem and may also originate from resinous materials occurring in the palisade and spongy mesophyll of leaves. Cutinite can form from either cuticles or from compressed cortical tissues of young roots. Charred leaves and charred secondary xylem and phloem comprise an important portion of the fusinitic and semifusinitic fractions of the coal. Pyrinite grains tend to occupy the cell cavities of early wood and ray cells. Differences between collinite and telinite developed during the peat stage, while progressive coalification tends to accentuate the lack of structure in the collinite.

  13. NOx and SO2 emission factors for Serbian lignite Kolubara

    Directory of Open Access Journals (Sweden)

    Jovanović Vladimir V.

    2012-01-01

    Full Text Available Emission factors are widely accepted tool for estimation of various pollutants emissions in USA and EU. Validity of emission factors is strongly related to experimental data on which they are based. This paper is a result of an effort to establish reliable NOx and SO2 emission factors for Serbian coals. The results of NOx and SO2 emissions estimations based on USA and EU emission factors from thermal power plants Nikola Tesla Obrenovac A and B utilizing the Serbian lignite Kolubara are compared with experimental data obtained during almost one decade (2000-2008 of emissions measurements. Experimental data are provided from regular annual emissions measurement along with operational parameters of the boiler and coal (lignite Kolubara ultimate and proximate analysis. Significant deviations of estimated from experimental data were observed for NOx, while the results for SO2 were satisfactory. Afterwards, the estimated and experimental data were plotted and linear regression between them established. Single parameter optimization was performed targeting the ideal slope of the regression line. Results of this optimization provided original NOx and SO2 emission factors for Kolubara lignite.

  14. The problem of enriching the Visonta lignites

    Energy Technology Data Exchange (ETDEWEB)

    Tarjan, G.

    1987-01-01

    The technology suggested by the Central Institute for Mining Development is critically analyzed. The minerals accompanying the lignite seams, especially the montmorillonite and its physical peculiarities are evaluated. The Visonta lignites contain inorganic components of about 45% in addition to about 21% clay. The investment costs are much lower in case of building a preparation system for lignite cleaning than the investment costs of the power plant planned only for raw lignite.

  15. Open-pit mining of lignite in Czechoslovakia

    Energy Technology Data Exchange (ETDEWEB)

    Hojdar, J.

    1987-06-01

    The complicated nature of the overburden in Czechoslovakian surface mines poses considerable difficulties to the construction of dumps and the stability of overburden slopes. Operations are further hindered by the extent of the investments required to sufficiently address these problems, and to access the lignite reserves. An example of this arose when it was discovered that the town of Most was situated above a huge deposit of coal. As a result, the entire town had to be demolished, and subsequently rebuilt a few kilometers away, in order to provide access to the 90 Mt of high quality lignite with a low stripping ratio (less than 1 m/sup 3//t). A particularly large expenditure was required to relocate a precious historical monument, a 12,000 t medieval gothic church, to a site 850 m from its original location, without dismantling the building.

  16. Bio-liquefaction/solubilization of low-rank Turkish lignites and characterization of the products

    Energy Technology Data Exchange (ETDEWEB)

    Yesim Basaran; Adil Denizli; Billur Sakintuna; Alpay Taralp; Yuda Yurum [Hacettepe University, Ankara (Turkey). Department of Environmental Sciences

    2003-08-01

    The effect of some white-rot fungi on the bio-liquefaction/solubilization of two low-rank Turkish coals and the chemical composition of the liquid products and the microbial mechanisms of coal conversion were investigated. Turkish Elbistan and Beypazari lignites were used in this study. The white-rot fungi received from various laboratories used in the bio-liquefaction/solubilization of the lignites were Pleurotus sajor-caju, Pleurotus sapidus, Pleurotus florida, Pleurotus ostreatus, Phanerochaete chrysosporium, and Coriolus versicolor. FT-IR spectra of raw and treated coal samples were measured, and bio-liquefied/solubilized coal samples were investigated by FT-IR and LC-MS techniques. The Coriolus versicolor fungus was determined to be most effective in bio-liquefying/solubilizing nitric acid-treated Elbistan lignite. In contrast, raw and nitric acid-treated Beypazari lignite seemed to be unaffected by the action of any kind of white-rot fungi. The liquid chromatogram of the water-soluble bio-liquefied/solubilized product contained four major peaks. Corresponding mass spectra of each peak indicated the presence of very complicated structures. 17 refs., 9 figs., 2 tabs.

  17. Distribution of various forms of organic nitrogen in a lignite macromolecule

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Proskuryakov, V.A.; Polovetskaya, O.S.; Shavyrina, O.A.; Ryl' tsova, S.V. [Lev Tolstoi State Pedalogical University, Tula (Russian Federation)

    2001-07-01

    The chemical composition of organic bases from tars of stepwise semicoking of lignite was studied. The features of distribution of organic nitrogen in a coal macromolecule and the most probable pathways of thermal degradation of the nitrogen-containing fragments were examined.

  18. Genetic relation of adamantanes from extracts and semicoking tars of lignites with the initial biological material

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Shvykin, A.Y.; Proskuryakov, V.A.; Podshibyakin, S.I. [Lev Tolstoi State Pedagogical University, Tula (Russian Federation)

    1999-11-01

    A genetic relation was revealed of adamantanes from extracts and semicoking tars of lignites with the relic terpenoid and steroid compounds. Probable pathways are suggested for transformation of the initial natural structures into adamantanes. The qualitative and quantitative compositions of adamantanes from crude oil and coal are compared.

  19. Naturally occurring radioactive materials (NORMs) generated from lignite-fired power plants in Kosovo.

    Science.gov (United States)

    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.

  20. Bio-solubilization of Chinese lignite Ⅱ: protein adsorption onto the lignite surface

    Institute of Scientific and Technical Information of China (English)

    YIN Su-dong; TAO Xiu-xiang; SHI Kai-yi

    2009-01-01

    Lignite bio-solubilization is a promising technology for converting solid lignite into oil. This study concerns the adsorption of lignite-solubilizing enzymes onto the lignite surface. Adsorption capacity, infrared spectral analysis and driving forces analysis are studied as a way to help understand the bio-solubilization mechanism. The results show that the amount of lignite bio-solubilization is proportional to the amount of adsorbed lignite-solubilizing enzymes. An increase in lignite-solubilizing enzyme adsorption of 10% leads to a 7% increase in lignite bio-solubilization. However, limited amounts of enzymes can be adsorbed by the lignite, thus resulting in low percentages of bio-solubilization. Infrared spectral analysis shows that side chains, such as hydroxyl and carbonyl, of the lignite structure are the main, and necessary, structures where lignite-solubilizing enzymes attachto the lignite. Furthermore, driving force analysis indicates that the electrostatic force between lignite and enzymes is the main adsorption mechanism. The forces are influenced by solution pH levels, the zeta potential of the lignite and the isoelectric points of the enzymes.

  1. Great Plains Coal Gasification Project: Quarterly technical progress report, April-June 1988 (Fourth fiscal quarter, 1987-1988)

    Energy Technology Data Exchange (ETDEWEB)

    1988-07-29

    This progress report describes the operation of the Great Plains Gasification Plant, including lignite coal production, SNG production, gas quality, by-products, and certain problems encountered. (LTN)

  2. Sustainable development of lignite production on open cast mines in Serbia

    Institute of Scientific and Technical Information of China (English)

    DANICIC Darko; MITROVIC Slobodan; PAVLOVIC Vladimir; KOVACEV Sava

    2009-01-01

    Energy sector represents a key industrial branch for national, environmental and economic success. With its exclusive access to domestic deposits, lignite industry represents a guarantor of reliable raw materials, offering long-term supply security based on verified reserves. Currently operated coalmines in Serbia (Kolubara and Kostolac) have production around 36 million tons of lignite, and over 108 million m3 of overburden. Consequently, sustainability of lignite production requires cost reduction and environmental protection, as well as capacity increase. In order to rationalise, and increase efficiency of Serbian lignite mines, it is necessary to focus the activities on major issues shown within the triangle of energy policy objectives (security of supply, competi-tive prices and environmental protection). Production process optimisation singled out several special programs. Equipment revi-talization and modernization is necessary taking into account that majority of the currently operated machinery has a life up to 25 years. Production process automation would enable high level of technical operation in the field of open cast mines management. Lack of coal quality uniformity is the permanent problem resulting by great amounts of coal reserves to be used uneconomically. Planning and training at all levels and finally cooperative software for business procedures and work order management. The measures suggested are a key precondition for maintaining competitive position of lignite production on international level.

  3. Pyrolysis of Indonesian coal

    Energy Technology Data Exchange (ETDEWEB)

    Rachimoellah; Endah [Institut Teknologi Sepuluh Nopemba, Surabaya (Indonesia). Department of Chemical Engineering; Karaman, N.; Kusuma, S.A. [UPN Surabaya, (Indonesia). Department of Chemical Engineering

    1997-04-01

    It has been estimated that there is 36 billion tons of coal resource potential in Indonesia. Over 21.4 billion tons is classified as low rank (lignitic) coal. The coal deposits are located mainly in Sumatra and Kalimantan. As an energy source, low rank coals are not widely used, because of their high moisture content, low calorific value and variable ash content. One of the key questions for utilizing low rank coal is whether lignite can be upgraded into another form which is more economically viable. In this study tests were carried out in a pilot plant fixed bed pyrolysis reactor unit provided with hopper, electric heater, coolers and product receivers. The yield of char, tar and gases was found to depend on temperature which also affected the composition of gas produced. Results also indicated the temperature and particle size giving maximum tar yield, gas concentration, and the atmosphere of inert nitrogen. 1 tab., 2 figs., 10 refs.

  4. Radionuclides in US coals

    Energy Technology Data Exchange (ETDEWEB)

    Bisselle, C. A.; Brown, R. D.

    1984-03-01

    The current state of knowledge with respect to radionuclide concentrations in US coals is discussed. Emphasis is placed on the levels of uranium in coal (and lignite) which are considered to represent a concern resulting from coal combustion; areas of the US where such levels have been found; and possible origins of high radionuclide levels in coal. The report reviews relevant studies and presents new data derived from a computerized search of radionuclide content in about 4000 coal samples collected throughout the coterminous US. 103 references, 5 figures, 5 tables.

  5. Corporate changes in the coal sector

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-02-20

    The article highlights major trends in the corporate structure and performance in the international coal business as recorded in the latest volume of `Coal companies worldwide` published by Sheffield Energy and Resources Information Services (SERIS). The document draws on information from 116 parent companies with coal or lignite mining operations, incorporating 400 subsidiaries, associates and joint ventures.

  6. Characterization of the mechanisms for coal solubilization by filamentous fungi

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, M.; Luna, N.; Monistrol, I.F.; Laborda, F. [Madrid Univ. (Spain). Dept. de Microbiologia y Parasitologia

    1997-12-31

    The mechanisms implicated on coal solubilization have been studied in this work. Two fungal strains (Trichoderma and Penicillium) has been isolated which were able to solubilize different kinds of Spanish coals (hard coal, subbituminous coal and lignite) when growing in liquid media in the presence of coal. Extracellular peroxidase, esterase and some times phenol oxidase enzymes were present in the culture supernatant when a high degree of coal solubilization was attained. Those enzymes could be involved in the coal attack. (orig.)

  7. Co-combustion of lignite with hazelnut shell

    Energy Technology Data Exchange (ETDEWEB)

    Haykiri-Acma, H.; Yaman, S. [Istanbul Technical University, Istanbul (Turkey). Chemical Engineering Department

    2005-07-01

    In this study, co-combustion characteristics of a Turkish lignite sample from Elbistan region, which is a low quality coal, with hazelnut shell was investigated. For this purpose, grounded samples (-250 {mu}m) were blended in the ratios of 90/10 and 80/20. Original samples and these blends were burned using a thermogravimetric analyzer from ambient to 1173 K with a heating rate of 20 K/min under dynamic dry air atmosphere of 40 cc/min. Derivative thermogravimetric analysis curves that derived from the results of the thermogravimetric analyses were compared and interpreted. 8 refs., 4 figs., 3 tabs.

  8. JV Task 90 - Activated Carbon Production from North Dakota Lignite

    Energy Technology Data Exchange (ETDEWEB)

    Steven Benson; Charlene Crocker; Rokan Zaman; Mark Musich; Edwin Olson

    2008-03-31

    The Energy & Environmental Research Center (EERC) has pursued a research program for producing activated carbon from North Dakota lignite that can be competitive with commercial-grade activated carbon. As part of this effort, small-scale production of activated carbon was produced from Fort Union lignite. A conceptual design of a commercial activated carbon production plant was drawn, and a market assessment was performed to determine likely revenue streams for the produced carbon. Activated carbon was produced from lignite coal in both laboratory-scale fixed-bed reactors and in a small pilot-scale rotary kiln. The EERC was successfully able to upgrade the laboratory-scale activated carbon production system to a pilot-scale rotary kiln system. The activated carbon produced from North Dakota lignite was superior to commercial grade DARCO{reg_sign} FGD and Rheinbraun's HOK activated coke product with respect to iodine number. The iodine number of North Dakota lignite-derived activated carbon was between 600 and 800 mg I{sub 2}/g, whereas the iodine number of DARCO FGD was between 500 and 600 mg I{sub 2}/g, and the iodine number of Rheinbraun's HOK activated coke product was around 275 mg I{sub 2}/g. The EERC performed both bench-scale and pilot-scale mercury capture tests using the activated carbon made under various optimization process conditions. For comparison, the mercury capture capability of commercial DARCO FGD was also tested. The lab-scale apparatus is a thin fixed-bed mercury-screening system, which has been used by the EERC for many mercury capture screen tests. The pilot-scale systems included two combustion units, both equipped with an electrostatic precipitator (ESP). Activated carbons were also tested in a slipstream baghouse at a Texas power plant. The results indicated that the activated carbon produced from North Dakota lignite coal is capable of removing mercury from flue gas. The tests showed that activated carbon with the greatest

  9. Stepwise demineralisation and chemical isolation of the mineral matter of Goynuk lignite

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Yavuz, R.; Kucukbayrak, S.; Taptik, Y. [Istanbul Technical University, Istanbul (Turkey). Dept. of Chemical Engineering, Chemical & Metallurgical Engineering Faculty

    2001-12-01

    The mineral matter of coal contains a number of inorganic constituents which play an important role in almost all coal utilisation systems. In this study, an alternative method was applied to separate the mineral matter content of a Turkish lignite. Goynuk lignite was treated, in sequence, with acetic acid, ammonia, hydrochloric acid, hydrofluoric acid and nitric acid at 70{sup o}C for 60 min in order to remove individual mineral species. After each stage, the lignite was treated with performic acid, the product of reaction between hydrogen peroxide and formic acid, at 50{sup o}C. The organic coal matrix was decomposed as a result of performic acid oxidation, and consequently, the recovered mineral species were isolated. Ammonia, which has the potential of chemical comminution, was used to increase the effects of the subsequent reagents and enhance the extent of separation between the organic and inorganic phases. In each mineral matter removal stage, the lignite was treated with the reagents of the previous stage, and then, a new reagent was added to investigate whether the last stage has a different effect on the mineral species. FT-IR and X-ray diffractometry techniques were used to determine the constituents of the isolated mineral matter after each stage.

  10. Supercritical Water as Nanomedium for Gasification of Lignite-Water Suspension

    Science.gov (United States)

    Korzh, Raisa; Bortyshevskyi, Valerii

    2016-05-01

    The gasification of an aqueous suspension of lignite from Alexandria coalfield (Ukraine) under the supercritical pressure was studied. The initial rates of the formation of hydrogen, carbon dioxide and methane were evaluated. The mutually stimulating interaction of the components of "brown coal-water-mineral matter" system was shown due to the influence of nanoscaled water medium on the formation of dipole-inductive, dispersive and ionic associates. In the temperature range of 300-450 °C, the oxygen source for gaseous products of the lignite supercritical gasification is mainly ion-associative nanoclustered water. The source of hydrogen at the subcritical temperature is the organic part of brown coal. For the supercritical water, the source of H is the nanoscale medium with ion associates. The last ones were responsible for the further transformation of coal.

  11. COMPLEX LONG TIME MEASUREMENTS CARRIED OUT ON LIGNITE HEAP ON SOKOLOVSKÉ UHELNÉ A.S.

    Directory of Open Access Journals (Sweden)

    Vlastimil MONI

    2013-04-01

    Full Text Available Long time in situ measurements carried out on selected lignite (brown coal heaps in the summer and winter season of 2012 and 2013 are described in this paper. The study was prepared in the frame of the research project TAČR No. TA01020351 “Research of prediction possibilities of infusion occurrence and following brown coal fuel self-ignition” supported in the programme ALFA. The main goal is to inform about the progress in the project focused on the research, development, and verifying of the complex methodology for an early identification of the start of an irreversible infusion state of lignite (brown coal mass tending to its ignition (fire.

  12. Supercritical Water as Nanomedium for Gasification of Lignite-Water Suspension.

    Science.gov (United States)

    Korzh, Raisa; Bortyshevskyi, Valerii

    2016-12-01

    The gasification of an aqueous suspension of lignite from Alexandria coalfield (Ukraine) under the supercritical pressure was studied. The initial rates of the formation of hydrogen, carbon dioxide and methane were evaluated. The mutually stimulating interaction of the components of "brown coal-water-mineral matter" system was shown due to the influence of nanoscaled water medium on the formation of dipole-inductive, dispersive and ionic associates. In the temperature range of 300-450 °C, the oxygen source for gaseous products of the lignite supercritical gasification is mainly ion-associative nanoclustered water. The source of hydrogen at the subcritical temperature is the organic part of brown coal. For the supercritical water, the source of H is the nanoscale medium with ion associates. The last ones were responsible for the further transformation of coal.

  13. Evolution lignite mesopore structure during drying. Effect of temperature and heating time

    Energy Technology Data Exchange (ETDEWEB)

    Salmas, C.E.; Tsetsekou, A.H.; Hatzilyberis, K.S.; Androutsopoulos, G.P. [National Technical University of Athens, Athens (Greece). Chemical Process Engineering Lab.

    2001-07-01

    The knowledge of the intrinsic pore structure of coals is significant in elucidating the kinetics of mass transport and chemical reaction that leads to design of more efficient coal combustion and conversion equipment. The results of pore structure studies of Greek lignite are reported in this work. Isothermal drying of Greek lignite samples, under vacuum, caused mesopore structure evolution despite the severe (similar to 50%) particle size contraction due to heating. Mesopore volume and surface area were increased as the drying temperature was raised to 200{degree}C while further drying up to 250 {degree}C caused a mesopore volume and surface area decrease. Lignite drying at 100{degree}C for up to 3 h resulted in a monotonic increase of the mesopore structure properties while heating for a longer period i.e., 6 h, despite a slight increase of weight loss, caused pore volume and surface area reduction. Nitrogen sorption (77 K) hysteresis data obtained for partially dried samples have been processed to deduce BET surface area and pore size distributions (PSD) by using both the Roberts and a new method based on a Corrugated Pore Structure Model (CPSM-nitrogen) methods. Bimodal PSD have been detected with one peak at 3 nm and the second at 20 nm while surface area varied over the range 2.98-5.30 m{sup 2}/g, Dry Greek lignite has shown a higher mesopore volume than that of several American and Canadian coals of varying rank. Mesopore volume distribution of dry Greek lignite, obtained from nitrogen sorption data, agree well with those deduced from mercury penetration data corrected for coal compressibility.

  14. Coal facies studies in Spain

    Energy Technology Data Exchange (ETDEWEB)

    Suarez-Ruiz, Isabel [INCAR (CSIC), Ap. Co., 73, 33080, Oviedo (Spain); Jimenez, Amalia [Geology, University of Oviedo, 33005, Oviedo (Spain)

    2004-04-23

    This work is a synthesis of the distribution of the main coal basins and sub-basins in Spain as well as the research carried out on their coal facies. The coal fields are distributed through the Paleozoic (mainly Pennsylvanian), Mesozoic (Cretaceous) and Cenozoic times. Peats also exist in the southeast Spain (Granada area), although these types of deposits are not included in this review. Spanish coal basins are both of a paralic and intramontane type and the coal rank is highly variable, from lignite in the case of the younger coal seams to anthracite for those of Carboniferous age.

  15. Macerals of Shengli Lignite in Inner Mongolia of China and Their Combustion Reactivity

    Directory of Open Access Journals (Sweden)

    Ying Yue Teng

    2016-01-01

    Full Text Available The macerals, including fusinitic coal containing 72.20% inertinite and xyloid coal containing 91.43% huminite, were separated from Shengli lignite using an optical microscope, and their combustion reactivity was examined by thermogravimetric analysis. Several combustion parameters, including ignition and burnout indices, were analyzed, and the combustion kinetics of the samples were calculated by regression. Fusinitic coal presented a porous structure, while xyloid coal presented a compact structure. The specific surface area of fusinitic coal was 2.5 times larger than that of xyloid coal, and the light-off temperature of the former was higher than that of the latter. However, the overall combustion reactivity of fusinitic coal was better than that of xyloid coal. The combustion processes of fusinitic and xyloid coals can be accurately described by both the homogeneous model and the shrinking core model. The features of xyloid coal agree with the shrinking core model when its conversion rate is 10%–90%. The activation energy of fusinitic coal during combustion can be divided into three phases, with the middle phase featuring the highest energy. The activation energy of xyloid coal is lower than that of fusinitic coal in the light-off phase, which may explain the low light-off temperature of this coal.

  16. Structural degradation of Thar lignite using MW1 fungal isolate: optimization studies

    Science.gov (United States)

    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.

  17. Origin and significance of high nickel and chromium concentrations in Pliocene lignite of the Kosovo Basin, Serbia

    Energy Technology Data Exchange (ETDEWEB)

    Ruppert, L.; Finkelman, R.; Boti, E.; Milosavljevic, M.; Tewalt, S.; Simon, M.; Dulong, F. [US Geological Survey, Reston, VA (United States)

    1996-03-01

    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 Palaeozoic peridotite at the nearby Glavica and Cikatovo Ni mines. 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 Palaeocene 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. 15 refs., 10 figs., 6 tabs.

  18. Coal in Bulgaria

    Energy Technology Data Exchange (ETDEWEB)

    McConville, L.; Broadbent, J.; Rousaki, K.

    1999-01-01

    Bulgaria`s national energy strategy includes plans to restructure the energy sector by introducing competition and privatisation, to promote energy efficiency and environmental protection and to prepare the country for integration into the EU energy market. Energy prices are still under government control and coal mining is heavily subsidised. Bulgaria is a major producer of coal, all of which is consumed locally. Most of the domestic production is low quality lignite used for electricity generation. Demand for hard coal is met by imports, mainly from the former USSR and the USA. Bulgaria generates almost half of its electricity needs from coal. Total reserves of lignite are estimated at 2.5 Gt. Coal production declined between 1987 and 1991 reflecting the economic disturbance following the break up of the USSR. In 1996, production was 32 Mt. The mining industry is being restructured as Bulgaria is slowly moving from a centrally-controlled economy to a market-based economy. Environmental damage as a result of coal production has been serious in Bulgaria, due to the use of low grade high sulphur content lignite. 84 refs., 10 figs., 9 tabs.

  19. Comparison of metallurgical coke and lignite coke for power generation in Thailand

    Science.gov (United States)

    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.

  20. Preliminary organic geochemical study of lignite from the Smederevsko Pomoravlje field (Kostolac basin, Serbia: Reconstruction of geological evolution and potential for rational utilization

    Directory of Open Access Journals (Sweden)

    Đoković Nataša

    2015-01-01

    Full Text Available The paper is aimed to determine the origin and geological evolution of lignites from Smederevsko Pomoravlje field (Kostolac Basin, Serbia. Possible rational utilization of coal is also considered. For this purpose numerous organic geochemical analyses have been applied to representative lignite samples. Obtained results showed that coal from the Smederevsko Pomoravlje field is typical humic coal. Peat-forming vegetation is dominated by gymnosperm plants. Coal forming plants belonged to the gymnosperm families Taxodiaceae, Cupressaceae, Phyllocladaceae and Pinaceae. Other precursors of organic matter (OM were microbial biomass, ferns and angiosperms. It is established that peatification was performed in neutral to slightly acidic, fresh water environment under anoxic to suboxic redox conditions. Maturity of OM is low in the phase of intense diagenetic processes. Biomarker compositions and values of corresponding parameters revealed that Smederevsko Pomoravlje field, Drmno field (Kostolac Basin and “A“ field (Kovin deposit represent a part of the unique lignite basin. Results of this study suggest possible rational utilization of the Smederevsko Pomoravlje lignites in thermal power plants. This is particularly related to samples from coal seam I. Significant amount of gas could be generated from lignites at higher maturities. Eight samples meet basic assumptions for effective gasification. [Projekat Ministarstva nauke Republike Srbije, br. 176006

  1. JV Task - 129 Advanced Conversion Test - Bulgarian Lignite

    Energy Technology Data Exchange (ETDEWEB)

    Michael Swanson; Everett Sondreal; Daniel Laudal; Douglas Hajicek; Ann Henderson; Brandon Pavlish

    2009-03-27

    The objectives of this Energy & Environmental Research Center (EERC) project were to evaluate Bulgarian lignite performance under both fluid-bed combustion and gasification conditions and provide a recommendation as to which technology would be the most technically feasible for the particular feedstock and also identify any potential operating issues (such as bed agglomeration, etc.) that may limit the applicability of a potential coal conversion technology. Gasification tests were run at the EERC in the 100-400-kg/hr transport reactor development unit (TRDU) on a 50-tonne sample of lignite supplied by the Bulgarian Lignite Power Project. The quality of the test sample was inferior to any coal previously tested in this unit, containing 50% ash at 26.7% moisture and having a higher heating value of 5043 kJ/kg after partial drying in preparation for testing. The tentative conclusion reached on the basis of tests in the TRDU is that oxygen-blown gasification of this high-ash Bulgarian lignite sample using the Kellogg, Brown, and Root (KBR) transport gasifier technology would not provide a syngas suitable for directly firing a gas turbine. After correcting for test conditions specific to the pilot-scale TRDU, including an unavoidably high heat loss and nitrogen dilution by transport air, the best-case heating value for oxygen-blown operation was estimated to be 3316 kJ/m{sup 3} for a commercial KRB transport gasifier. This heating value is about 80% of the minimum required for firing a gas turbine. Removing 50% of the carbon dioxide from the syngas would increase the heating value to 4583 kJ/m{sup 3}, i.e., to about 110% of the minimum requirement, and 95% removal would provide a heating value of 7080 kJ/m{sup 3}. Supplemental firing of natural gas would also allow the integrated gasification combined cycle (IGCC) technology to be utilized without having to remove CO{sub 2}. If removal of all nitrogen from the input gas streams such as the coal transport air were

  2. Coal char fragmentation during pulverized coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, L.L.

    1995-07-01

    A series of investigations of coal and char fragmentation during pulverized coal combustion is reported for a suite of coals ranging in rank from lignite to low-volatile (lv) bituminous coal under combustion conditions similar to those found in commercial-scale boilers. Experimental measurements are described that utilize identical particle sizing characteristics to determine initial and final size distributions. Mechanistic interpretation of the data suggest that coal fragmentation is an insignificant event and that char fragmentation is controlled by char structure. Chars forming cenospheres fragment more extensively than solid chars. Among the chars that fragment, large particles produce more fine material than small particles. In all cases, coal and char fragmentation are seen to be sufficiently minor as to be relatively insignificant factors influencing fly ash size distribution, particle loading, and char burnout.

  3. Petrological, geochemical and isotopic characteristics of lignite and calcified lignite from mining area Pesje, Velenje Basin, Slovenia

    Science.gov (United States)

    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

  4. Research of lignite oxidation kinetic parameters modified by CuSO4 and NaNO3 initiation additives

    Directory of Open Access Journals (Sweden)

    Larionov Kirill

    2017-01-01

    Full Text Available An experimental study and subsequent analytical assessment of activation energy change in lignite oxidation process with addition of NaNO3 and CuSO4 mineral salts were conducted. The results showed that injection of catalytic additives leads to reduction of coal activation energy and reaction initial temperature.

  5. Peat swamps at Giral lignite field of Barmer basin, Rajasthan,Western India: understanding the evolution through petrological modelling

    Institute of Scientific and Technical Information of China (English)

    Prakash K.Singh; P.K.Rajak; M.P.Singh; V.K.Singh; A.S.Naik; Alok K.Singh

    2016-01-01

    The lignite samples collected from Giral lignite field of Barmer basin have been subjected to petrological investigation.The data generated has been discussed to understand the evolution of the paleomires of these lignites.The present study reveals that these low rank C coals are chiefly composed of huminite group macerals,mainly telohuminite and detrohuminite,while liptinite and inertinite group macerals occur in subordinate amounts.Not much variation in the maceral composition from Seam-I to Seam-Ⅷ has been observed.Barmer lignites are characterized by a very high GI (>10) and moderate TPI indicating topogenous mire in the basin which was permanently flooded.The GI and TPI values and the petrography-based facies critical models indicate that these lignites originated mostly under wet forest swamp to clastic marsh having telmatic to limno-telmatic conditions with a moderate rate of subsidence and a very slow fall in ground water table.Further,the GWI and VI values are suggestive of mesotrophic to rheotrophic hydrological conditions having the dominance of herbaceous to marginal aquatic vegetation.There were spells of periodic drowning of peat especially during the formation of Seam-Ⅶ.Moderately high concentration of calcium in these lignites along with the presence of framboidal pyrite indicate enhanced sulphate-reducing bacterial activity present in carbonate and sulphate-rich waters in the basin during peat formation.

  6. Coal; Le charbon

    Energy Technology Data Exchange (ETDEWEB)

    Teissie, J.; Bourgogne, D. de; Bautin, F. [TotalFinaElf, La Defense, 92 - Courbevoie (France)

    2001-12-15

    Coal world production represents 3.5 billions of tons, plus 900 millions of tons of lignite. 50% of coal is used for power generation, 16% by steel making industry, 5% by cement plants, and 29% for space heating and by other industries like carbo-chemistry. Coal reserves are enormous, about 1000 billions of tons (i.e. 250 years of consumption with the present day rate) but their exploitation will be in competition with less costly and less polluting energy sources. This documents treats of all aspects of coal: origin, composition, calorific value, classification, resources, reserves, production, international trade, sectoral consumption, cost, retail price, safety aspects of coal mining, environmental impacts (solid and gaseous effluents), different technologies of coal-fired power plants and their relative efficiency, alternative solutions for the recovery of coal energy (fuel cells, liquefaction). (J.S.)

  7. Test results of beneficiation of lignites deriving from opencast mines

    Energy Technology Data Exchange (ETDEWEB)

    Bacskai, G.; Schmied, L.; Szabo, I.

    1987-01-01

    The possible varieties of lignite beneficiation of Hungarian lignites as well as the experiences from abroad are discussed. Improvement of the quality of lignites includes homogenization, pre-sorting, wet sorting and pre-drying. The possibilities of producing cemented lignite briquette, of the thermal benefication are outlined. The anticipated costs and length of time necessary to establish lignite briquetting plants in Hungary under different economic conditions are listed.

  8. Comparison of artificial maturation of lignite in hydrous and nonhydrous conditions

    Science.gov (United States)

    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

  9. Coal facies studies in Australia

    Energy Technology Data Exchange (ETDEWEB)

    Crosdale, Peter J. [Coalseam Gas Research Institute, School of Earth Sciences, James Cook University, Townsville, Qld 4814 (Australia)

    2004-04-23

    Despite the economic importance of coal to the Australian economy, detailed studies of controls on variation in coal type are remarkably few. However, important contributions have been made in the understanding of coal facies development. Tertiary lignite deposits of the Gippsland Basin provide key insights into the development of lithotype cyclicity and its relationship to relative sea-level changes, with individual paling-up cycles being correlated to parasequences. Studies of Permian hard coals have identified relationships between coal type and surrounding sediments. Unfortunately, these relationships have been widely over-interpreted in a manner that has diminished their real value.

  10. Germany's lignite industry in 2012; Die deutsche Braunkohlenindustrie im Jahr 2012

    Energy Technology Data Exchange (ETDEWEB)

    Maassen, Uwe [Bundesverband Braunkohle, Statistik der Kohlenwirtschaft e.V., Koeln (Germany); Schiffer, Hans-Wilhelm [RWE Aktiengesellschaft, Essen (Germany). CEA-W Allgemeine Wirtschaftspolitik/Wissenschaft

    2013-05-15

    From 2011 to 2012, Germany's domestic lignite output edged up to 5.1% from 176.5 mill. t to 185.4 mill. t. This figure is equivalent to a net calorific value of 57.2 mill. tce. Of the total output, 166.3 mill. t, or some 90%, was used in utility power plants for the public supply, i.e. 5.7% more than in the previous year. In addition, 15.1 mill. t was input in the factories of the lignite-mining industry to make solid products, while 3.0 mill. t was used to generate electricity in mine-mouth power plants. Other sales of raw lignite and changes in stocks accounted for 1.0 mill. t. Lignite made a 25.7% contribution toward Germany's total power generation in 2012. In 2012, lignite had a 12.1% share in primary-energy consumption balance after mineral oil (33.1%), natural gas (21.6%) and hard coal (12.2%). Renewable resources cover 11.6%, while nuclear energy accounts for 8.0% and other energy sources for 1.4%. With output of 57.2 mill. tce, lignite held a share of 38.4% in Germany's primary-energy production of some 149 mill. tce in 2012. The contributions made by other energy carriers to primary-energy production in 2012 were as follows: 11.1 mill. tce hard coal, 13.3 mill. tce gas, 3.8 mill. tce mineral oil, 54.0 mill. tce renewables, and 9.5 mill. tce other energy sources. Of the total electricity amount that Germany produced in 2012, 25.7% was accounted for by lignite. This means that lignite led the ranking of the most important input energies for electricity generation in 2012, followed by renewables with 22.1%, hard coal with 19.1%, nuclear energy with 16.1% and gas with 11.3%. Other energy sources made a 5.7% contribution to total gross power generation. The most important ratios for the contributions made by the various lignite-mining areas to Germany's energy supply are shown. CO{sub 2} emissions from lignite rose 5.1% from 173.9 mill. t in 2011 to 182.8 mill. t in 2012. In the total period from 1990 to 2012, a decline of 159.4 mill. t, or

  11. Possible linkages between lignite aquifers, pathogenic microbes, and renal pelvic cancer in northwestern Louisiana, USA

    Science.gov (United States)

    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.

  12. Possible linkages between lignite aquifers, pathogenic microbes, and renal pelvic cancer in northwestern Louisiana, USA.

    Science.gov (United States)

    Bunnell, Joseph E; Tatu, Calin A; Bushon, Rebecca N; Stoeckel, Donald M; Brady, Amie M G; Beck, Marisa; Lerch, Harry E; McGee, Benton; Hanson, Bradford C; Shi, Runhua; Orem, William H

    2006-12-01

    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 PO(4) and NH(3), 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.

  13. Coal facies studies in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Kalkreuth, Wolfgang D. [Laboratorio de Carvao e de Petrologia Organica, Instituto de Geociencias, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Goncalves, 9500, 91501-970 Porto Alegre, RS (Brazil)

    2004-04-23

    The present study is a compilation of published data on coal facies studies in Canada based on coal petrological and other methods. The geological age of the coals range from the Devonian coal deposits in Arctic Canada to coals of Tertiary age in the Western Canada Sedimentary Basin, intermontane British Columbia and Arctic Canada. In terms of rank, the coal deposits studied range from lignite to low volatile bituminous. Coal petrological methods include maceral and microlithotype analyses, frequently integrated with data from palynological and geochemical analyses. Most recently, a number of studies have applied sequence stratigraphic concepts to the coal-bearing strata including the interpretation of coal petrological data in the context of this concept.

  14. Co-pyrolysis of lignite and sugar beet pulp

    Energy Technology Data Exchange (ETDEWEB)

    Yilgin, M.; Deveci Duranay, N.; Pehlivan, D. [Firat University, Chemical Engineering Department, 23279 Elazig (Turkey)

    2010-05-15

    Today, worldwide studies have been undertaken on the biomass usage and co-conversion of biomass and coal to seek out alternative fuels for supplying energy in an environmental friendly way. The objective of this work is to study co-pyrolysis of lignite and sugar beet pulp in 50/50 (wt./wt.) ratio of blend pellets, to elucidate their thermal behaviour under pyrolysis conditions and to assess major decomposition products in terms of their yields. A special chamber, which has enabled very fast heating rates, was used in the pyrolysis experiments carried at 600 C. The results were interpreted in the light of liquid, solid and gaseous yields, resulting from thermal decomposition, and kinetics of thermogravimetric analysis. Proximate volatile matter and ash contents of the blends were different compared to those found by using individual values. Sugar beet pulp decomposed faster within a relatively narrow temperature range than lignite and underwent a significant shrinkage during pyrolysis. It was found that the chars left behind after the flash pyrolysis of these pellets at 600 C have substantial amounts of volatile matter that would evolve upon further heating. (author)

  15. Behavior study of trace elements in pulverized lignite, bottom ash, and fly ash of Amyntaio power station, Greece.

    Science.gov (United States)

    Megalovasilis, Pavlos; Papastergios, Georgios; Filippidis, Anestis

    2013-07-01

    The Kozani-Ptolemais-Amyntaio basin constitutes the principal coal field of Greece. Approximately 50% of the total power production of Greece is generated by five power stations operating in the area. Lignite samples, together with the corresponding fly ash and bottom ash were collected, over a period of 3 months, from the power plant of Amyntaio and analyzed for their content in 16 trace elements. The results indicate that Y, Nb, U, Rb, Zr, Ni, Pb, Ba, Zn, Sr, Cu, and Th demonstrate an organic affinity during the combustion of lignite, while V has an inorganic affinity. Three elements (Co, Cr, and Sc) show an intermediate affinity.

  16. JV Task - 129 Advanced Conversion Test - Bulgarian Lignite

    Energy Technology Data Exchange (ETDEWEB)

    Michael Swanson; Everett Sondreal; Daniel Laudal; Douglas Hajicek; Ann Henderson; Brandon Pavlish

    2009-03-27

    The objectives of this Energy & Environmental Research Center (EERC) project were to evaluate Bulgarian lignite performance under both fluid-bed combustion and gasification conditions and provide a recommendation as to which technology would be the most technically feasible for the particular feedstock and also identify any potential operating issues (such as bed agglomeration, etc.) that may limit the applicability of a potential coal conversion technology. Gasification tests were run at the EERC in the 100-400-kg/hr transport reactor development unit (TRDU) on a 50-tonne sample of lignite supplied by the Bulgarian Lignite Power Project. The quality of the test sample was inferior to any coal previously tested in this unit, containing 50% ash at 26.7% moisture and having a higher heating value of 5043 kJ/kg after partial drying in preparation for testing. The tentative conclusion reached on the basis of tests in the TRDU is that oxygen-blown gasification of this high-ash Bulgarian lignite sample using the Kellogg, Brown, and Root (KBR) transport gasifier technology would not provide a syngas suitable for directly firing a gas turbine. After correcting for test conditions specific to the pilot-scale TRDU, including an unavoidably high heat loss and nitrogen dilution by transport air, the best-case heating value for oxygen-blown operation was estimated to be 3316 kJ/m{sup 3} for a commercial KRB transport gasifier. This heating value is about 80% of the minimum required for firing a gas turbine. Removing 50% of the carbon dioxide from the syngas would increase the heating value to 4583 kJ/m{sup 3}, i.e., to about 110% of the minimum requirement, and 95% removal would provide a heating value of 7080 kJ/m{sup 3}. Supplemental firing of natural gas would also allow the integrated gasification combined cycle (IGCC) technology to be utilized without having to remove CO{sub 2}. If removal of all nitrogen from the input gas streams such as the coal transport air were

  17. Biogasification of low-rank coal

    Energy Technology Data Exchange (ETDEWEB)

    Harding, R.; Czarnecki, S.; Isbister, J.; Barik, S. (ARCTECH, Inc., Chantilly, VA (United States))

    1993-02-01

    ARCTECH is developing a coal biogasification technology, The MicGAS Process'' for producing clean fuel forms such as methane. The overall objective of this research project was to characterize and construct an efficient coal gasifying capable of converting Texas lignite to methane. The technical feasibility for bioconversion of Texas lignite to methane, volatile fatty acids, alcohols, and other soluble organic products has been demonstrated. Several biogasification were evaluated for their ability to degrade low-rank coals to methane, and Mic-1 a mixed culture derived from a wood-eating- Zootermopsis termite species, was identified as the most active and efficient for biogasification of Texas lignite. Parameters such as pH, temperature, redox potential, coal particle size, coal solids loadings, culture age, nutrient amendments, and biomass concentration were studied to determine the optimum conditions required for efficient biogasification of coal. Analytical methods for monitoring the production of methane, degradation intermediates, and biomass were developed. Most significant achievements were: (1) development of analytical methodology to monitor coal biogasification; (2) confirmation of biogasification efficiency of Mic-1 culture; (3) ability of Mic-1 consortium to retain coal-degrading activity when grown in the absence of coal; and (4) significantly higher (ca. 26%) methane production from micronized coal (ca. 10 gm) than from larger coal particle sizes.

  18. Coal mining situation in the Federal Republic of Germany. The 1st quarter 2017; Zur Lage des Kohlenbergbaus in der Bundesrepublik Deutschland. 1. Vierteljahr 2017

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2017-06-14

    The paper reports on the coal mining in the Federal Republic of Germany in the 1st quarter of 2017. Statistical data are presented for mining, exports and imports of hard coal and lignite and for employees.

  19. Coal mining situation in the Federal Republic of Germany. The 1st quarter 2016; Zur Lage des Kohlenbergbaus in der Bundesrepublik Deutschland. 1. Vierteljahr 2016

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-06-06

    The paper reports on the coal mining in the Federal Republic of Germany in the 1st quarter of 2016. Statistical data are presented for mining, exports and imports of hard coal and lignite and for employees.

  20. Effect of biomass on temperatures of sintering and initial deformation of lignite ash

    Energy Technology Data Exchange (ETDEWEB)

    H. Haykiri-Acma; S. Yama; S. Kucukbayrak [Istanbul Technical University, Istanbul (Turkey). Faculty of Chemical and Metallurgical Engineering

    2010-10-15

    Sintering temperatures and the initial deformation temperatures of ashes from Turkish Elbistan lignite, and biomass species such as hazelnut shell and rice husk were investigated up to 1450{sup o}C by Heating Microscope Technique. Sintering temperatures were found 1300, 1269, and 1320{sup o}C for hazelnut shell, rice husk, and lignite, respectively, while the initial deformation temperatures were >1450, 1370, and >1450{sup o}C. Lignite/biomass blends were prepared by adding of biomass into coal in the ratios of 5 or 10 wt.%, and then effects of biomass presence on sintering temperature and the initial deformation temperature were tested. It was determined that the addition of potassium-rich hazelnut shell reduced the sintering temperatures to 919 and 730{sup o}C for the blends of 5 and 10 wt.%, respectively. Also, initial deformation temperature dropped to 788{sup o}C in case of the blend of 10 wt.%. Such a big antagonistic influence of hazelnut shell on the thermal behaviour of ash is attributed to the interaction of potassium from biomass with silicon compounds found in mineral matter of lignite. In addition, concentration of CaO may be another reason for this. On the other hand, the presence of rice husk showed limited effect on the sintering temperature as well the initial deformation temperature. 20 refs., 3 figs., 5 tabs.

  1. Possible linkages between lignite aquifers, pathogenic microbes, and renal pelvic cancer in northwestern Louisiana, USA

    Energy Technology Data Exchange (ETDEWEB)

    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.H.; Orem, W.H. [USGS, Reston, VA (United States)

    2006-12-15

    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 PO{sub 4} and NH{sub 3}, and 13 chemical elements. Presence of human pathogenic leptospires was detected in four out of eight (50%) of the surface water sites sampled.

  2. Liquefaction and/or solubilization of Spanish coals by newly isolated microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Monistrol, I.F.; Laborda, F. (Universidad de Alcala de Henares, Alcala de Henares (Spain). Dept. de Microbiologia Parasitologia)

    1994-11-01

    A screening procedure has been set up for isolating microorganisms capable of liquefying coal. Spanish coals were used in the tests, namely a brown lignite from Galicia, sub-bituminous coal from Teruel and hard coal from Minas Figaredo S.A. (Asturias). Among the isolated strains several microorganisms proved capable of liquefying untreated lignite. When lignites were pretreated a more intense and rapid liquefaction was achieved, chelating agents being among the best pretreatment. None of the isolated microorganisms could satisfactorily liquefy sub-bituminous and hard coals in solid media. On the other hand, some fungi grew specifically on the untreated coals, engulfing them and in many cases a soft slurry was obtained. Several of the isolated microorganisms were able to solubilize all three untreated Spanish coals in liquid media. Coal solubilization was measured spectrophotometrically at 300, 400 and 450 nm. 5 refs., 10 figs., 3 tabs.

  3. Perspectives of the non-energetic use of lignite in Germany

    Energy Technology Data Exchange (ETDEWEB)

    Keller, D.; Sailer, B. [RWE Power AG, Essen (Germany)

    2013-11-01

    RWE Power AG as integral part of RWE Generation SE has been active in the development and commercialization of coal gasification routes for many years. RWE Generation SE is one of Europe's leading electricity producers and combines the expertise of the power plant specialists Essent (NL), RWE npower (UK) and RWE Power (D). A globally increasing freight traffic and accompanying fuel demand is anticipated in the future. This higher demand will probably result in an increase in crude oil price in the course of the next years. There will also be a disproportionately high increase in fuel prices additionally to the increase in the crude oil price due to an increasing treatment effort within refineries. Therefore the substitution of crude oil becomes more and more attractive in view of economical perspectives and security of supply. Crude oil is not only to be substituted as feedstock for fuels but also for the chemical industry. Coal has been and will be the most important feedstock for this. Especially its gasification enables various routes. In Germany there is also an interesting perspective for Coal-to-Liquids and Coal-to-Gas or CtL/CtG as the non-energetic use of coal is abbreviated. Lignite is available regardless of any market impacts and currently faces a change in its use for power generation due to the increasing use of renewable energies. Hence lignite is an attractive feedstock for CtL/CtG in Germany. The construction of a commercial size CtL/CtG plant means a billion Euro investment. So a reliable economic evaluation is inevitable. Today all CtL/CtG routes miss commercial competitiveness to the conventional production by some ten percents. In case the current upward price trend of crude oil continues CtL/CtG might become viable in the near future. The production of synthetic fuels appears most attractive in view of a substantial market potential. The further commercialization of gasification routes in Germany requires R and D activities especially

  4. Kinetics of lignite pyrolysis in fixed bed and entrained flow reactors. Technical report No. 17

    Energy Technology Data Exchange (ETDEWEB)

    Scaroni, A. W.; Walker, Jr., P. L.

    1979-08-01

    A laminar flow isothermal furnace has been constructed and used to study lignite pyrolysis in nitrogen at temperatures between 700/sup 0/ and 1000/sup 0/C. Particles of a Texas lignite (Darco Seam) between 41 and 201 microns in mean diameter, are found to flow down the furnace tube with velocities approximated by the summation of the gas plug-flow velocity and particle free-fall velocities. Some particle shrinkage and density changes occur during pyrolysis. Pyrolysis rate is particle size independent and increases with increase in temperature over the range of operating conditions. Ultimate yield of volatiles in the isothermal furnace, which is calculated from the linear relationship between weight loss and change in proximate volatile matter, is 66% of the original dry-ash-free coal and is particle size independent and relatively temperature independent. Ultimate yields of volatiles from fixed beds of pulverized coal are smaller than for dispersed particles of the same size. Proximate volatile matter for the lignite is, for example, 51% of the original dry-ash-free coal. Heating rates drop from about 10,000/sup 0/C/s in the isothermal furnace to about 20/sup 0/C/s in the proximate volatile matter test. Pyrolysis rates decrease and display particle size dependency in fixed beds. This implication of physical rate control is attributed to heat transfer limitations. It is proposed that pyrolysis rate and therefore residence time of volatiles in the fixed bed are important parameters affecting the preponderance of secondary char forming reactions.Also important is the total particle external surface area in the bed. Secondary char formation is considered responsible for yields of volatiles lower than the true volatile content of the lignite as measured in the isothermal furnace.

  5. The coal-bearing Cenozoic As Pontes Basin (northwestern Spain): geological influence on coal characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Cabrera, L.; Hagemann, H.W.; Pickel, W.; Saez, A. [Universitat de Barcelona, Barcelona (Spain). Dept. de Geologia Dinamica, Geofisica i Paleontologia

    1995-03-01

    Lignite deposits in the Cenozoic As Pontes strike-slip basin (northwestern Spain) were formed as a function of specific paleoclimatic conditions and tectonic evolution of the basin. During the early evolutionary stages, the presence of active normal faults and thrusts inside the basin resulted in two subbasins with distinct differences in sedimentary records, with respect to lignite seam occurrence, thickness, areal extent and lithotype development. In contrast, during the late evolutionary stages the basin was not split and a more homogeneous sedimentary record in terms of coal seam occurrence and lithotype characteristics developed. A total of 26 lignite samples, distributed along the basin infill, were analyzed by organic petrography and geochemistry. All are lignite B (ASTM). The lignites deposited during lower basin infill sedimentation (unit 1 and 2) are dark, matrix-rich, mainly huminitic brown coals, with minor bright, liptinitic-rich coal lithotypes. The dark huminitic coals in these units show sedimentological and paleontological evidence of lacustrine influence. Lignites in the upper basin infill (Unit 4) are almost exclusively matrix-rich, huminitic brown coals. The overall coal petrological data trend recorded from the lower to the upper basin infill units agrees with the stratigraphic and sedimentological data, which show a trend of increasingly drier conditions. Development of bright, liptinite-enriched lignite layers was widespread during the early basin evolutionary stages and was influenced by punctuated water-table oscillations. Sedimentological, petrological and organic geochemical data suggest that, although the paleoenvironments where peat deposition took place did not undergo dramatic changes, they were affected by distinguishable variations, linked mostly to the evolution of basin morphology and basin water balance. 52 refs., 8 figs., 3 tabs.

  6. Land reclamation beautifies coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Coblentz, B. [MSU Ag Communications (United States)

    2009-07-15

    The article explains how the Mississippi Agricultural and Forestry Experiments station, MAFES, has helped prepare land exploited by strip mining at North American Coal Corporation's Red Hills Mine. The 5,800 acre lignite mine is over 200 ft deep and uncovers six layers of coal. About 100 acres of land a year is mined and reclaimed, mostly as pine plantations. 5 photos.

  7. Future lignite mines of Serbia; Zukunftsbraunkohletagebaue in Serbien

    Energy Technology Data Exchange (ETDEWEB)

    Hoehna, Ullrich; Schmidt, Uwe [Vattenfall Europe Mining AG, Cottbus (Germany); Pavlovic, Vladimir [Belgrade Univ. (RS). Opencast Mining Dept.

    2010-01-15

    The Pre-feasibility Study on Selection of Limitation and Opening of Open Pit Mines Radljevo and South Field with Comparative Overview of Technical and Economic Aspects of Coal Mining for the Selection of Priority Coal Supplier of CHP Kolubara B has been prepared by Vattenfall Europe Mining Consulting (VEMC) and the University of Belgrade Faculty of Mining and Geology (UB-FMG) as subcontractor. Strategic and development plans of Electric Power Industry of Serbia anticipate the construction of new thermal power plant capacities in the Kolubara region requiring the provision of necessary coal amounts. One of the essential questions which needed to be analysed and defined more precisely by this study was the question of fuel supply to these new capacities as the precondition for finding the strategic partners in the construction of new power capacities. The RB Kolubara mining company produces around 30 Mt/a of lignite mainly from the large opencast mines Field D and Tamnava-West. It supplies most of it to the existing TPP in Kolubara and TPP Nicola Tesla A and B in Obrenovac. (orig.)

  8. 褐煤及其热解产品利用现状%Utilization status of lignite and pyrolysis products

    Institute of Scientific and Technical Information of China (English)

    刘军; 邹涛; 初茉; 畅志兵; 林益安

    2014-01-01

    为了提高褐煤利用率,介绍了国内褐煤资源的储量形态、分布。分析了目前褐煤的利用途径,包括共伴生资源的利用、直接燃烧、干燥脱水与成型、气化、液化、制水煤浆与热解。并进一步分析了褐煤热解气、液、固产品的利用方向。提出了褐煤半焦利用的新方法,即利用半焦干法气化,或将半焦和热解废水等制成水煤浆,通过湿法气化制得合成气,再通过甲烷化催化剂将合成气制成甲烷,或将合成气通过费托合成制成汽油柴油。%In order to improve the utilization rate of lignite,the lignite reserves and distribution status was introduced. The utilization ways of lignite,including associated resources utilization,lignite direct combustion,dehydration and briquetting,gasification,liquefaction,py-rolysis and coal water mixture preparation were introduced. Then the using direction of gas,liquid and solid productions of lignite pyrolysis were further investigated. The authors put forward some new utilization methods of lignitic semi-coke, including gasifying the semi-coke by the dry gasification and preparing coal water mixture ( CWM) with semi-coke and pyrolytic waste water. The CWM was gasified to pro-duce syngas by the wet gasification. Then the syngas was used to prepare methane with methanation catalysts, or compound petrol and diesel by Fischer-Tropsch synthesis.

  9. Co-firing of pine chips with Turkish lignites in 750kWth circulating fluidized bed combustion system.

    Science.gov (United States)

    Atimtay, Aysel T; Kayahan, Ufuk; Unlu, Alper; Engin, Berrin; Varol, Murat; Olgun, Hayati; Atakul, Husnu

    2017-01-01

    Two Turkish lignites which have different sulfur levels (2-2.9% dry) and ash levels (17-25% dry) were combusted with a Turkish forest red pine chips in a 750kW-thermal capacity circulating fluidized bed combustor (CFBC) system. The combustion temperature was held at 850±50°C. Flue gas emissions were measured by Gasmet DX-4000 flue gas analyzer. Two lignites were combusted alone, and then limestone was added to lignites to reduce SO2 emissions. Ca/S=3 was used. 30% percent of red pine chips were added to the lignites for co-firing experiments without limestone in order to see the biomass effects. The results showed that with limestone addition SO2 concentration was reduced below the limit values for all lignites. CO emissions are high at low excess air ratios, gets lower as the excess air ratio increases. During co-firing experiments the temperature in the freeboard was 100-150°C higher as compared to coal combustion experiments.

  10. Combustion behavior of different kinds of torrefied biomass and their blends with lignite.

    Science.gov (United States)

    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.

  11. Ultrasonic depolymerization of aqueous polyvinyl alcohol.

    Science.gov (United States)

    Grönroos, A; Pirkonen, P; Heikkinen, J; Ihalainen, J; Mursunen, H; Sekki, H

    2001-07-01

    Ultrasonication has proved to be a highly advantageous method for depolymerizing macromolecules because it reduces their molecular weight simply by splitting the most susceptible chemical bond without causing any changes in the chemical nature of the polymer. Most of the effects involved in controlling molecular weight can be attributed to the large shear gradients and shock waves generated around collapsing cavitation bubbles. In general, for any polymer degradation process to become acceptable to industry, it is necessary to be able to specify the sonication conditions which lead to a particular relative molar mass distribution. This necessitates the identification of the appropriate irradiation power, temperature, concentration and irradiation time. According to the results of this study the reactors constructed worked well in depolymerization and it was possible to degrade aqueous polyvinyl alcohol (PVA) polymer with ultrasound. The most extensive degradation took place at the lowest frequency used in this study, i.e. 23 kHz, when the input power was above the cavitation threshold and at the lowest test concentration of PVA, i.e. 1% (w/w). Thus this study confirms the general assumption that the shear forces generated by the rapid motion of the solvent following cavitational collapse are responsible for the breakage of the chemical bonds within the polymer. The effect of polymer concentration can be interpreted in terms of the increase in viscosity with concentration, causing the molecules to become less mobile in solution and the velocity gradients around the collapsing bubbles to therefore become smaller.

  12. Desulphurization of coal using borax

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Kuecuekbayrak, S. [Istanbul Technical Univ. (Turkey). Chemical and Metallurgical Engineering Faculty

    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.

  13. Health impacts of coal and coal use: Possible solutions

    Science.gov (United States)

    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.

  14. Technology and use of lignite. Proceedings of the tenth biennial lignite symposium

    Energy Technology Data Exchange (ETDEWEB)

    Kube, W. R.; Gronhovd, G. H. [comps.

    1979-01-01

    The symposium on the technology and use of lignite was sponsored by the US Department of Energy and the University of North Dakota, and held at Grand Forks, North Dakota, May 30-31, 1979. Twenty-one papers from the proceedings of this tenth biennial lignite symposium have been entered into EDB and ERA and three also into EAPA. The papers discuss lignite deposits in the USA, mining plans, gasification and in-situ gasification, and combustion in fossil-fuel power plants. (LTN)

  15. Basic properties of Japanese and foreign coals selected for liquefaction. 1. A consideration of the method for proximate analysis of coals

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, R.

    1984-10-01

    The use of thermogravimetry for the proximate analysis of coals is compared with the Japanese Standard method (JIS M8812). The thermogravimetric method was found to be applicable to a wide range of brown coals, lignites and bituminous coals providing a rapid and simple method requiring only a small sample and giving a direct determination of fixed carbon.

  16. The shell coal gasification process

    Energy Technology Data Exchange (ETDEWEB)

    Koenders, L.O.M.; Zuideveld, P.O. [Shell Internationale Petroleum Maatschappij B.V., The Hague (Netherlands)

    1995-12-01

    Future Integrated Coal Gasification Combined Cycle (ICGCC) power plants will have superior environmental performance and efficiency. The Shell Coal Gasification Process (SCGP) is a clean coal technology, which can convert a wide range of coals into clean syngas for high efficiency electricity generation in an ICGCC plant. SCGP flexibility has been demonstrated for high-rank bituminous coals to low rank lignites and petroleum coke, and the process is well suited for combined cycle power generation, resulting in efficiencies of 42 to 46% (LHV), depending on choice of coal and gas turbine efficiency. In the Netherlands, a 250 MWe coal gasification combined cycle plant based on Shell technology has been built by Demkolec, a development partnership of the Dutch Electricity Generating Board (N.V. Sep). The construction of the unit was completed end 1993 and is now followed by start-up and a 3 year demonstration period, after that the plant will be part of the Dutch electricity generating system.

  17. Metathesis depolymerization for removable surfactant templates.

    Energy Technology Data Exchange (ETDEWEB)

    Zifer, Thomas (Sandia National Laboratories, Livermore, CA); Wheeler, David Roger; Rahimian, Kamayar; McElhanon, James Ross (Sandia National Laboratories, Livermore, CA); Long, Timothy Michael; Jamison, Gregory Marks; Loy, Douglas Anson (Los Alamos National Laboratories, Los Alamos, NM); Kline, Steven R. (National Institute of Standards and Technology, Gaithersburg, MD); Simmons, Blake Alexander (Sandia National Laboratories, Livermore, CA)

    2005-03-01

    Current methodologies for the production of meso- and nanoporous materials include the use of a surfactant to produce a self-assembled template around which the material is formed. However, post-production surfactant removal often requires centrifugation, calcination, and/or solvent washing which can damage the initially formed material architecture(s). Surfactants that can be disassembled into easily removable fragments following material preparation would minimize processing damage to the material structure, facilitating formation of templated hybrid architectures. Herein, we describe the design and synthesis of novel cationic and anionic surfactants with regularly spaced unsaturation in their hydrophobic hydrocarbon tails and the first application of ring closing metathesis depolymerization to surfactant degradation resulting in the mild, facile decomposition of these new compounds to produce relatively volatile nonsurface active remnants.

  18. Thermogravimetric investigation of hydrochar-lignite co-combustion.

    Science.gov (United States)

    Liu, Zhengang; Quek, Augustine; Kent Hoekman, S; Srinivasan, M P; Balasubramanian, R

    2012-11-01

    Co-combustion of hydrochar with lignite was investigated by means of thermogravimetric analysis. Hydrochars were produced from coconut fibers and eucalyptus leaves under hydrothermal conditions at 250°C. The hydrochar was added in varying amounts to lignite for combustion. The results indicated that hydrothermal treatment decreased the volatile matter content and increased the fixed carbon content of the biomaterials. The elevated energy density and decreased ash content of the hydrochar improved its combustion behavior when co-fired with lignite for energy production. The hydrochars derived from coconut fiber and eucalyptus leaves had similar chemical compositions and showed similar influences on lignite combustion. Hydrochar addition increased the burnout and shortened the combustion range of the hydrochar-lignite blends. High combustion efficiency was observed due to the synergistic interactions between hydrochar and lignite during the co-combustion process. A kinetic study showed that the combustion process of hydrochar-lignite blends followed first-order reaction rates.

  19. Enhancing Carbon Reactivity in Mercury Control in Lignite-Fired Systems

    Energy Technology Data Exchange (ETDEWEB)

    Chad Wocken; Michael Holmes; John Pavlish; Jeffrey Thompson; Katie Brandt; Brandon Pavlish; Dennis Laudal; Kevin Galbreath; Michelle Olderbak

    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 the 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

  20. Characteristics of Pyrolytic Topping in Fluidized Bed for Different Volatile Coals

    Science.gov (United States)

    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.

  1. Origin and significance of high nickel and chromium concentrations in pliocene lignite of the Kosovo Basin, Serbia

    Science.gov (United States)

    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.

  2. Pyrolysis of phenols from lignite semicoking tar

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Ryltsova, S.V.; Proskuryakov, V.A.; Rozental, D.A.; Polovetskaya, O.S.; Martynov, V.Y.; Chilachava, K.B.

    2000-07-01

    Pyrolysis of phenols from lignite semicoking tar at 750-900 {degree}C and contact time of 0.5-6.0 s was studied. The yields of pyrocarbon, pyrolysis gas, and liquid products and the group and component composition of the liquid products and pyrolysis gas were determined. The main groups of compounds in liquid products were analysed.

  3. Inorganic constituents of some Turkish lignites

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Taptik, Y.; Yavuz, R.; Kuecuekbayrak, S. [Istanbul Technical Univ., Istanbul (Turkey). Chemical and Metallurgical Engineering Faculty

    1996-12-31

    In this study the mineral matter contents of two different Turkish lignite samples from Cayirhan and Tuncbilek regions were isolated by means of mild oxidation of organic matrix applying H{sub 2}O{sub 2}/HCOOH treatment. The isolated minerals were analyzed by XRD and FTIR techniques and constituents of the minerals were investigated qualitatively.

  4. Hydrogeological Issues Concerning the Thar Lignite Prospect

    Directory of Open Access Journals (Sweden)

    R. N. Singh

    2012-12-01

    Full Text Available The paper is concerned with the hydrogeological appraisal of the proposed mining operations in theThar lignite field in Sindh, Pakistan. The Thar coalfield covers an area of approximately 9000km2 andcontains three lignite seams lying at depth of 130m to 250 m. In the Thar lignite field, the presence ofthree main aquifers induces pore pressure in the rock mass surrounding the lignite seams and makes highwall slopes potentially unsafe. It is, therefore, necessary to dewater the rock mass before commencingmining excavations. The paper describes the proposed mine dewatering scheme to facilitatedepressurising of the rock mass surrounding the mining excavations. Inflow prediction of groundwater tothe surface mining excavation was carried out using a SEEP/W finite element software package. Thesimulation results show that the ground water inflow from the Top aquifer is 114m3/d, from theIntermediate confined aquifer is 141m3/d and from the Bottom confined aquifer is 1.28 x 105 m3 /d. Theseresults were compared with the analytical solutions which indicated that the relative error of estimation ofinflow quantities varies from 3.4 % to 6.4%.

  5. Fuel briquettes from biomass-lignite blends

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Haykiri-Acma, H.; Sesen, K.; Kuecuekbayrak, S. [Chemical Engineering Department, Chemical and Metallurgical Engineering Faculty, Istanbul Technical University, Maslak, 80626 Istanbul (Turkey)

    2001-08-01

    In this study, a western Turkish lignite (Kuetahya-Seyitoemer) was blended with some biomass samples such as molasses, pine cone, olive refuse, sawdust, paper mill waste, and cotton refuse, and these blends was used in the production of fuel briquettes. Blends were subjected to briquetting pressures between 50 and 250 MPa; the ratio of biomass to lignite was changed between 0 and 30 wt.%. The mechanical strength of obtained briquettes was investigated considering shatter index and compressive strength. Effects of the ratio of biomass to lignite and applied pressure on the strength of the briquettes were examined. This study indicated that the mechanical strength of the briquettes produced from Kuetahya-Seyitoemer lignite can be improved by adding some biomass samples. For example, the presence of paper mill waste increased the shatter index of the briquettes obtained. Similarly, sawdust and paper mill waste increased compressive strength of the briquettes. Water resistance of the briquettes can be augmented by adding olive refuse, cotton refuse, pine cone or paper mill waste.

  6. Fluid bed drying as upgrading technology for feasible treatment of Kolubara lignite

    Directory of Open Access Journals (Sweden)

    Erić Milić D.

    2016-01-01

    Full Text Available An overview of the current status of low-rank coal upgrading technologies is presented in the paper, particularly with respect to drying and dewatering procedures. In order to calculate the significant parameters of the moisture removal process, a model of convective coal drying in a fluid bed, based on the two-phase (bubbling fluidization model proposed by Kunii and Levenspiel, is developed and presented. Product-specific data (intraparticle mass transfer, gas-solid moisture equilibrium related to the particular coal variety addressed here (Kolubara lignite are obtained through preliminary investigations. Effective thermal conductivity of the packed bed as defined by Zehner/Bauer/Schlünder is used to define heat transfer mechanisms occurring in the suspension phase of the fluid bed. A completely new set of experimental data obtained has been successfully used to validate the model additionally. [Projekat Ministarstva nauke Republike Srbije, br. TR33050 i III42010

  7. Study on pyrolysis gas in thermal extraction of Bai Yinhua lignite with industrial washing oil

    Science.gov (United States)

    Cui, Y. M.; Lian, X. P.; Zhao, F. Y.; Xu, Y. Q.; Hu, Y. Q.; Yuan, Z. K.; Hao, X. R.

    2016-08-01

    Industrial washing oil as solvent, pyrolysis gas produced from Bai Yinhua lignite during thermal extraction was studied by gas chromatography. The effects of temperature and solvent coal ration on coal pyrolysis gas were investigated. The results showed that: Pyrolysis gas produced mainly in CO, CO2, O2, H2, CH4, and so on, in which the total amount of oxygen containing compounds nearly 40%, significant effects of deoxidation was achieved. The increase of heat extraction temperature can significantly increase the degree of bond breaking and the gas formation rate, the gas yield and the rate of oxygen increase significantly, while the gas yield increases with the decrease of the solvent coal ration.

  8. The hydrocarbon potential, thermal maturity, sequence stratigraphic setting and depositional palaeoenvironment of carbonaceous shale and lignite successions of Panandhro, northwestern Kutch Basin, Gujarat, Western India

    Science.gov (United States)

    Sahay, Vinay

    2011-03-01

    The objective of the present paper is to provide geochemical and palynological data to characterize lignites and carbonaceous shales from Panandhro, northwestern Kutch Basin, Gujarat, Western India, in terms of their hydrocarbon potential, thermal maturity, sequence stratigraphic settings and depositional palaeoenvironment. The samples, collected in Panandhro lignite mine, belong to Naredi Formation of Late Paleocene-Early Eocene age. The geochemical results are based on proximate analysis, ultimate analysis, X-ray diffraction and Rock-Eval py-rolysis analyses, whereas palynological data include palynofossil composition and thermal alteration index (TAI). The TOC, hydrogen index (HI), cracked hydrocarbon (S2), bitumen index (BI), quality index (QI), and the total genetic potential (S1+S2) values indicate that the studied lignites and carbonaceous shales have good source rock potential. The organic matter is predominantly of type II and type II/III kerogen, which has potential to generate oil as well as gas. Thermal maturity determined from thermal alteration index (TAI), Tmax and production index (PI) indicates that the organic matter is immature, and in the diagenesis stage of organic matter transformation. The deposition of the studied carbonaceous shales and lignites took place in palaeoenvironments varying from brackish mangrove to freshwater swamp. This study indicates that the proportion of ferns, palms, volatile matter content, S/C, H/C ratios, as well as the presence of siderite and quartz can be used as an indicator of accommodation trends in the coal depositional system. The Panandhro carbonaceous shales and lignites were deposited during the lowstand systems tract with many cycles of small magnitude trangressive-regressive phases. Thus, the geochemistry and ecological palynology are useful not only for the investigation of coal quality and origin, but also to infer accommodation space settings of the mire. This can be gainfully utilized in the coal

  9. Drmno lignite field (Kostolac basin, Serbia: Origin and palaeoenvironmental implications from petrological and organic geochemical studies

    Directory of Open Access Journals (Sweden)

    Stojanović Ksenija

    2012-01-01

    Full Text Available The objective of the study was to determine the origin and to reconstruct the geological evolution of lignites from the Drmno field (Kostolac Basin, Serbia. For this purpose petrological and organic geochemical analyses were used. Coal from the Drmno field is typical humic coal. Peat-forming vegetation dominated by decay of resistant gymnosperm (coniferous plants, followed by prokaryotic organisms and angiosperms. Coal forming plants belonged to the gymnosperm families Taxodiaceae, Podocarpaceae, Cupressaceae, Araucariaceae, Phyllocladaceae and Pinaceae. Peatification was performed in neutral to slightly acidic, fresh water environment. Considering that organic matter of Drmno lignites was deposited at the same time, in the relatively constant climate, it could be supposed that climate probably had only small impact on peatification. Therefore, variations in compositions of macerals and biomarkers indicate changes in the water level, due to seasonal drying of the mire, which caused vegetation differences in the palaeoplant communities and changes of redox conditions (from anoxic to slightly oxic during peatification. Diagenetic transformations of the organic matter were mainly governed by microbial activity, rather than thermal alteration.

  10. The role of coal consumption in the economic growth of the Polish economy in transition

    Energy Technology Data Exchange (ETDEWEB)

    Gurgul, Henryk, E-mail: henryk.gurgul@gmail.co [Department of Applications of Mathematics in Economics, Faculty of Management, AGH University of Science and Technology, Gramatyka 10 st., 30-067 Cracow (Poland); Lach, Lukasz, E-mail: lukilach1983@o2.p [Department of Applications of Mathematics in Economics, Faculty of Management, AGH University of Science and Technology, Gramatyka 10 st., 30-067 Cracow (Poland)

    2011-04-15

    The main goal of this paper is an analysis of the causal links between quarterly coal consumption in the Polish economy and GDP. For the sake of accurate computation an additional variable - employment - was also taken into account. Computations conducted for the period Q1 2000 to Q4 2009 by means of recent causality techniques confirmed the neutrality of hard coal usage with respect to economic growth. On the other hand, calculations for the pairs lignite-GDP and total coal consumption-GDP showed the existence of a significant nonlinear causality from coal usage to economic growth. This is clear evidence for claiming that lignite plays an important role in the economic growth of the Polish economy. Furthermore, each coal-related variable was found to have a nonlinear causal impact on employment. Because of the relatively short length of available time series we additionally applied bootstrap critical values. The empirical results computed by both methods did not exhibit significant differences. These results have important policy implications. In general, our findings support the hypothesis that closing hard coal mines in Poland should have no significant repercussions on economic growth. However, this does not seem to be true for lignite mines. - Research highlights: {yields} The reduction of hard coal consumption should not hamper economic growth in Poland. {yields} Lignite consumption is an important factor determining economic growth in Poland. {yields} The usage of lignite and hard coal has a causal impact on employment in Poland.

  11. Synergy in devolatilization characteristics of lignite and hazelnut shell during co-pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    H. Haykiri-Acma; S. Yaman [Istanbul Technical University, Istanbul (Turkey). Chemical and Metallurgical Engineering Faculty, Chemical Engineering Department

    2007-02-15

    Coal/biomass blends were prepared in the lignite/biomass ratios of 98:2, 96:4, 94:6, 92:8, 90:10, and 80:20 using a Turkish lignite from Elbistan region and hazelnut shell. Co-pyrolysis characteristics were investigated in a thermogravimetric analyzer (TGA) from ambient to 1173 K with a linear heating rate of 20 K/min under dynamic nitrogen flow of 40 ml/min. Char products from pyrolysis were investigated using XRD and SEM techniques. Devolatilization yields from the blends were evaluated in a synergistic manner and found that the overall yields for all the blends exceeded the expected yields which calculated from the additive behavior. As regards to devolatilization characteristics in given temperature intervals, it was concluded that there was significant synergy between 400 and 600 K, whereas additive behavior took place beyond 600 K. No evidence of synergy was observed in the activation energies. It was also concluded that the addition of hazelnut shell into lignite contributed to the sulfur fixing potential of char in the form of CaS and CaSO{sub 4}. 21 refs., 5 figs., 4 tabs.

  12. The effect of mixing ratio on co-pyrolysis of lignite and rapeseed

    Energy Technology Data Exchange (ETDEWEB)

    Onay, O [Anadolu Univ., Eskisehir (Turkey). Porsuk Vocational School; Usta, C.; Kockar, O.M. [Anadolu Univ., Eskisehir (Turkey). Dept. of Chemical Engineering

    2007-07-01

    This study was conducted to determine the influence of lignite on the yield and chemical structure of bio-oil produced from rapeseed using a fast pyrolysis technique. The rapeseed and lignite mixtures were pyrolyzed in a fixed bed reactor. Heating rates and temperatures were controlled by a PID controller. Char yield after pyrolysis was determined from the overall weight losses of the reactor tube, while the liquid phase was collected in a glass liner. Experiments were conducted using a range of blending ratios. While final pyrolysis temperatures were set at 550 degrees C. An elemental analyzer was used to characterize the rapeseed and pyrolysis bio-oils. Fourier transform infrared analysis (FTIR) was used to conduct functional group compositional analyses. The study showed that conversion degree increased with temperature increases. Yields of both conversion and oil increased with biomass concentration. However, distribution between conversion and oil was influenced by the blending ratio. A maximum yield of oil was obtained with a 5 per cent blending ratio of lignite. It was concluded that the co-pyrolysis of rapeseed and coal at a temperature of 550 degrees C increases production by more than 11 per cent. 14 refs., 3 tabs., 3 figs.

  13. The treatment of a deposited lignite pyrolysis wastewater by adsorption using activated carbon and activated coke

    Energy Technology Data Exchange (ETDEWEB)

    Wiessner, A.; Remmler, M.; Kuschk, P.; Stottmeister, U. [UFZ-Umweltforschungszentrum Leipzig-Halle GmbH, Leipzig (Germany). Dept. of Remediation Research

    1998-07-31

    This paper investigated activated carbon and activated coke adsorption for the treatment of highly contaminated discoloured industrial wastewater with a wide molecular size distribution of organic compounds. Lignite pyrolysis wastewater from a filled open-cast coal mine was used for continuous and discontinuous experiments. The investigations were performed using water samples taken from various depths of the deposits ponds. A comparison of the capacities of the adsorption materials used showed, that because of its large number of macro and mesopores, activated coke is more suitable for wastewater treatment and in addition cheaper than activated carbon.

  14. Organic compounds in water extracts of coal: links to Balkan endemic nephropathy.

    Science.gov (United States)

    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.

  15. Lignin depolymerization by fungal secretomes and a microbial sink

    Energy Technology Data Exchange (ETDEWEB)

    Salvachúa, Davinia; Katahira, Rui; Cleveland, Nicholas S.; Khanna, Payal; Resch, Michael G.; Black, Brenna A.; Purvine, Samuel O.; Zink, Erika M.; Prieto, Alicia; Martínez, María J.; Martínez, Angel T.; Simmons, Blake A.; Gladden, John M.; Beckham, Gregg T.

    2016-08-25

    In Nature, powerful oxidative enzymes secreted by white rot fungi and some bacteria catalyze lignin depolymerization and some microbes are able to catabolize the resulting aromatic compounds as carbon and energy sources. Taken together, these two processes offer a potential route for microbial valorization of lignin. However, many challenges remain in realizing this concept, including that oxidative enzymes responsible for lignin depolymerization also catalyze polymerization of low molecular weight (LMW) lignin. Here, multiple basidiomycete secretomes were screened for ligninolytic enzyme activities in the presence of a residual lignin solid stream from a corn stover biorefinery, dubbed DMR-EH (Deacetylation, Mechanical Refining, and Enzymatic Hydrolysis) lignin. Two selected fungal secretomes, with high levels of laccases and peroxidases, were utilized for DMR-EH lignin depolymerization assays. The secretome from Pleurotus eryngii, which exhibited the highest laccase activity, reduced the lignin average molecular weight by 63% and 75% at pH 7 compared to the Mw of the control treated at the same conditions and the initial DMR-EH lignin, respectively, and was applied in further depolymerization assays as a function of time. As repolymerization was observed after 3 days of incubation, an aromatic-catabolic microbe (Pseudomonas putida KT2440) was incubated with the fungal secretome and DMR-EH lignin. These experiments demonstrated that the presence of the bacterium enhances lignin depolymerization, likely due to bacterial catabolism of LMW lignin, which may partially prevent repolymerization. In addition, proteomics was also applied to the P. eryngii secretome to identify the enzymes present in the fungal cocktail utilized for the depolymerization assays, which highlighted a significant number of glucose/ methanol/choline (GMC) oxidoreductases and laccases. Overall, this study demonstrates that ligninolytic enzymes can be used to partially depolymerize a solid, high

  16. Lignin Depolymerization by Fungal Secretomes and a Microbial Sink

    Energy Technology Data Exchange (ETDEWEB)

    Salvachua, Davinia; Katahira, Rui; Cleveland, Nicholas S.; Khanna, Payal; Resch, Michael G.; Black, Brenna A.; Purvine, Samuel O.; Zink, Erika M.; Prieto, Alicia; Martinez, Maria J.; Martinez, Angel T.; Simmons, Blake A.; Gladden, John M.; Beckham, Gregg T.

    2016-11-21

    In Nature, powerful oxidative enzymes secreted by white rot fungi and some bacteria catalyze lignin depolymerization and some microbes are able to catabolize the resulting aromatic compounds as carbon and energy sources. Taken together, these two processes offer a potential route for microbial valorization of lignin. However, many challenges remain in realizing this concept, including that oxidative enzymes responsible for lignin depolymerization also catalyze polymerization of low molecular weight (LMW) lignin. Here, multiple basidiomycete secretomes were screened for ligninolytic enzyme activities in the presence of a residual lignin solid stream from a corn stover biorefinery, dubbed DMR-EH (Deacetylation, Mechanical Refining, and Enzymatic Hydrolysis) lignin. Two selected fungal secretomes, with high levels of laccases and peroxidases, were utilized for DMR-EH lignin depolymerization assays. The secretome from Pleurotus eryngii, which exhibited the highest laccase activity, reduced the lignin average molecular weight (Mw) by 63% and 75% at pH 7 compared to the Mw of the control treated at the same conditions and the initial DMR-EH lignin, respectively, and was applied in further depolymerization assays as a function of time. As repolymerization was observed after 3 days of incubation, an aromatic-catabolic microbe (Pseudomonas putida KT2440) was incubated with the fungal secretome and DMR-EH lignin. These experiments demonstrated that the presence of the bacterium enhances lignin depolymerization, likely due to bacterial catabolism of LMW lignin, which may partially prevent repolymerization. In addition, proteomics was also applied to the P. eryngii secretome to identify the enzymes present in the fungal cocktail utilized for the depolymerization assays, which highlighted a significant number of glucose/methanol/choline (GMC) oxidoreductases and laccases. Overall, this study demonstrates that ligninolytic enzymes can be used to partially depolymerize a solid

  17. Oxydesulphurization of coal using trona mineral

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Kuecuekbayrak, S. [Istanbul Technical Univ. (Turkey)

    1995-12-31

    In this study, the desulphurization of coal by oxydesulphunzation method using raw trona mineral was investigated. The experiments were carried out on a Turkish lignite sample which has both high pyritic and high organic sulphur contents. Some experimental parameters such as temperature, partial pressure of oxygen, concentration and time were investigated.

  18. Aspects of solid state 13C CPMAS NMR spectroscopy in coals from the Balkan peninsula

    Directory of Open Access Journals (Sweden)

    ANDREAS GEORGAKOPOULOS

    2003-09-01

    Full Text Available The cross-polarized magic-angle-spinning NMR (CPMAS-NMR technique was used in this work to assess the carbon distribution in coals of different rank (peat, lignite, xylite, sub-bituminous coal from important deposits in Greece and Bulgaria. The technique is assumed to be only semiquantitative, due to a number of interferences, such as spinning side bands (SSB in the spectra, paramagnetic species in the samples, and low or remote protonation of aromatic carbons. The Bulgarian sub-bituminous coal shows the greatest amounts of aromatic structures. The lignite sample from the Drama basin, Northern Greece, is relatively unaltered and largely unweathered, and shows the greatest amounts of aliphatic groups. The 13C-NMR spectra of Pliocene lignites from endemic areas in Serbia and Montenegro and Bosnia, taken from published papers, show significantly more intense resonances for methoxyl, phenolic, and polysaccharide moieties compared to the Drama lignite NMR spectrum. Xylite reveals high contents of carbohydrates.

  19. Combustion characteristics and air pollutant formation during oxy-fuel co-combustion of microalgae and lignite.

    Science.gov (United States)

    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.

  20. Flocculation of the Visonta lignite sludges by polyacrylamides

    Energy Technology Data Exchange (ETDEWEB)

    Lakatos-Szabo, J.; Lakatos, I.

    1986-01-01

    Laboratory tests on the flocculation of clay-lignite sludges by polyelectrolytes proved the strongly heterodisperse suspensions to be suitable to sedimenting and filtering after the treatment by anionic polyacrylamides. The formation of large-sized flocs of loose structure allows troublefree filtration and dewatering. The specific flocculant consumption of dewatering is 1 to 2 kg per lignite ton. In this manner the preparation costs of lignite can be lowered.

  1. Processing the Visonta lignite for utilization in power plants

    Energy Technology Data Exchange (ETDEWEB)

    Gimpl, E.

    1985-01-01

    To utilize the Visonta lignite in power plants, laboratory, semi-industrial and industrial experiments were carried out. In the enrichment process, the parameters of the mensual quality fluctuations, the expected grain size distribution of the lignite, and the average ash content are to be known. Different enrichment processes as well as their results are discussed. In harmony with the obtained results the optimal lignite processing technology is described.

  2. Pyrolysis of hydrocarbons from lignite semicoking tar

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Ryl' tsova, S.V.; Proskuryakov, V.A.; Rozental, D.A.; Polovetskaya, O.S.

    2000-07-01

    Pyrolysis of hydrocarbons from lignite semicoking tar in the range 750-900{degree}C at a contact time within 0.5-6.0 s was studied. The yields of pyrocarbons, pyrolysis gas, and liquid products and the group and component compositions of the liquid and gaseous products were determined. The optimal pyrolysis parameters from the viewpoint of obtaining the maximal yield of particular 'secondary' hydrocarbons were recommended.

  3. Pyrolysis of asphaltenes from lignite semicoking tar

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Ryl' tsova, S.V.; Rozental, D.A.; Proskuryakov, V.A.; Polovetskaya, O.S.

    2000-07-01

    Pyrolysis of asphaltenes from lignite semicoking tar in the range 750-900{degree}C at a contact time within 0.5-6.0 s was studied. The yields of pyrocarbons, pyrolysis gas, and liquid products and the group composition of the liquid products were determined. The total analysis of the major groups of compounds present in the liquid products was performed, and the optimal conditions of pyrolysis, from the viewpoint of preparation of particular compounds, were recommended.

  4. Foraminiferal biostratigraphy of lignite mines of Kutch,India:Age of lignite and fossil vertebrates

    Institute of Scientific and Technical Information of China (English)

    Pratul; Kumar; Saraswati; Sonal; Khanolkar; Dalta; Surya; Narayana; Raju; Suryendu; Dutta; Santanu; Banerjee

    2014-01-01

    The lignite deposits of Kutch, India are stratigraphically referred to the Naredi Formation and considered to be Early Eocene in age. The biostratigraphy of the older mine at Panandhro and a newly opened mine at Matanomadh has constrained the upper age limit of lignite to the early Bartonian. Its lower age may extend to the late Lutetian. Temporally the formation of lignite corresponds to the warming event of the Middle Eocene and suggests a humid climate at the onset of the warming. The previous palynological studies have already suggested dominance of tropical angiospermic pollen. A diverse assemblage of fossil whales and other vertebrates, many of them supposedly the oldest representatives, were reported from Panandhro mine. These were initially assigned to the Early Eocene and later to the Lute? tian age. The present biostratigraphic study revises their age to the Early Bartonian.

  5. Hydrogeological assessment of the Thar lignite prospect

    Energy Technology Data Exchange (ETDEWEB)

    Singh, R.N.; Stace, R. [Nottingham Centre of Geomechanics (United Kingdom). Dept. of Civil Engineering, Faculty of Engineering; Pathan, A.G. [Mehran Univ. of Engineering and Technology, Shahrood (Iran, Islamic Republic of). Faculty of Mining, Petroleum and Geophysics; Atkins, A.S. [Staffordshire Univ., Stafford (United Kingdom). Faculty of Computing, Engineering and Technology

    2010-07-01

    This paper described a hydrogeological appraisal conducted at a proposed mine site in the Thar lignite field in Pakistan. The field contains an estimate 9 billion tonnes of lignite reserves. Three aquifers surrounding the lignite seams are inducing pore pressure in the rock mass and creating hazardous conditions at the site's high wall slopes. Groundwater inflow predictions were conducted using a finite element-based software package. The study was conducted to calculate dewatering quantities in order to ensure stability during excavation activities. Pumping tests conducted in boreholes at the bottom aquifer were used to determine permeability coefficients. Pumping rates from the 3 aquifers were calculated using the equivalent well approach. Results of the simulations were used to predict groundwater inflow from the bottom aquifer to the fully penetrating pit of the mine under steady state flow conditions. Results of the study indicated that 20 pumping out wells equipped with 150 mm diameter motor pumps will be required over a period of 10 years to achieve an overall dewatering rate of 0.6 m{sup 3}/s for the top aquifer. High head borehole pumps are needed for the intermediate and bottom-confined aquifers. 6 refs., 2 tabs., 2 figs.

  6. Specific industrial medicine in lignite mining

    Energy Technology Data Exchange (ETDEWEB)

    Zerlett, G.; Toussaint, R.; Hilfert, R.; Koehne, G.

    1986-11-01

    Lignite is almost exclusively mined open-cast in West Germany. Mining is carried out at present in deep open-cast mines (with depths up to 400 m) using modern mining conveyer techniques with large-scale equipment (rotary bucket excavators and thickeners) conveyer belt and railway links as well as earth-moving equipment (accessory equipment). Specific occupational diseases are not known in lignite mining. Occupational diseases in the sense of degenerative processes of the lumbar spine and avulsion fractures of spinous processes of the lower cervical spine in drivers of earth-moving equipment as a result of whole-body vibration stress have been observed. In the context of occupational disease and industrial accident prevention, close collaboration and a division of labor between industrial physicians and safety engineers of ergonomics specialists have proved to be very efficient. Industrial medical preventive examinations based on statutory regulations and the lignite mining ordinance have a long tradition and are given a great deal of space. First aid at work is organized in a largely decentralized manner owing to the extensiveness of the mining area. The industrial medical care of the employees takes place on site in the various sections (open-cast mining, workshops, brickett factories, processing units etc.). The entire medical technical diagnostics is carried out centrally in an industrial medical center.

  7. Mutagenicity of eluent by hot water extraction of various coals: Effect of chlorination

    Energy Technology Data Exchange (ETDEWEB)

    Tsunenori Nakajima; Hiroyuki Hasegawa; Satomi Nakamata; Hirokazu Takanashi; Akira Ohki [Kagoshima University, Kagoshima (Japan). Department of Bioengineering

    2008-10-15

    Six kinds of powdery coals (two bituminous coals, two sub-bituminous coals, and two lignites) were extracted by hot water, and the eluents obtained were analyzed for total organic carbon (TOC), absorbance at 260 nm (A260), and pH. The TOC in the eluents decreased in the order, lignites > sub-bituminous coals > bituminous coals. The eluents of lignite gave high A{sub 260}/TOC values and fairly low pH compared to other coals. Chemical structure of the organic matter eluted from coals was discussed with the aid of FTIR analysis. The coal eluents were analyzed by the Ames mutagenicity assay using Salmonella typhimurium TA100 and TA98 strains, and no mutagenicity was observed for all of the six coals. However, especially for the lignites, chlorination of the eluents produced an appreciable mutagenicity, and the expression of mutagenicity was dependent upon the type of coal. The mutagenicity was extinguished when metabolic activation (rat liver homogenate, +S9) was applied. 26 refs., 6 tabs.

  8. Formation and retention of methane in coal

    Energy Technology Data Exchange (ETDEWEB)

    Hucka, V.J.; Bodily, D.M.; Huang, H.

    1992-05-15

    The formation and retention of methane in coalbeds was studied for ten Utah coal samples, one Colorado coal sample and eight coal samples from the Argonne Premium Coal Sample Bank.Methane gas content of the Utah and Colorado coals varied from zero to 9 cm{sup 3}/g. The Utah coals were all high volatile bituminous coals. The Colorado coal was a gassy medium volatile bituminous coal. The Argonne coals cover a range or rank from lignite to low volatile bituminous coal and were used to determine the effect of rank in laboratory studies. The methane content of six selected Utah coal seams and the Colorado coal seam was measured in situ using a special sample collection device and a bubble desorbometer. Coal samples were collected at each measurement site for laboratory analysis. The cleat and joint system was evaluated for the coal and surrounding rocks and geological conditions were noted. Permeability measurements were performed on selected samples and all samples were analyzed for proximate and ultimate analysis, petrographic analysis, {sup 13}C NMR dipolar-dephasing spectroscopy, and density analysis. The observed methane adsorption behavior was correlated with the chemical structure and physical properties of the coals.

  9. Activated-Lignite-Based Super Large Granular Slow-Release Fertilizers Improve Apple Tree Growth: Synthesis, Characterizations, and Laboratory and Field Evaluations.

    Science.gov (United States)

    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/CeO2 nanoparticle catalyst to improve its pore structure and nutrient absorption. Results indicate that the adsorption ability of the activated lignite to NO3(-), NH4(+), H2PO4(-), 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.

  10. Lignite Drying and Dewatering Technologies%褐煤干燥脱水技术

    Institute of Scientific and Technical Information of China (English)

    孟顺; 孙绍增; 赵广播

    2013-01-01

    With a high water content, lignite has a low efficiency for direct combustion power generation. The lignite drying and dewatering technology can effectively lower the water content of lignite- and enhance its competitive power. On this basis, the authors studied and analyzed the principles of the following technologies, namely, flue gas drying technology , steam drying technology (tube type drying and fluidized bed steam drying) , hydrothermal dewatering technology, mechanical thermal dehydration (MTE) technology and upgraded brown coal (UBC) technology. Moreover,they also contrasted and analyzed the pressure, temperature, removing state, dewatering effectiveness, pore structure and re-absorption characteristics of various drying and dewatering technologies. The mechanical thermal dehydration technology can change the pore structure of brown coal and prevent from re-absorption, thus achieving a relatively high dewatering efficiency with a low energy consumption rate. It is of major significance for China to develop novel drying and dewatering technologies with due consideration of the brown coal distribution features of China to lower the water content of coal from its source, realize an economic transportation of coal and enhance the power generation efficiency of power plants.%褐煤含水量高,直接燃烧发电效率低.褐煤干燥脱水技术能有效降低褐煤含水量,提高其竞争力.研究介绍了烟气干燥技术、蒸汽干燥(管式干燥,流化床蒸汽干燥)、水热脱水技术、机械热力脱水技术(MTE)和热油干燥技术(UBC)5种褐煤干燥脱水技术的原理;对比分析了不同干燥脱水技术的压力、温度、脱除状态、脱水效率、孔隙结构和重吸收特性;机械热力脱水技术(MTE)可以改变褐煤孔隙结构、防止重吸收、脱水效率较高和能耗低.结合我国褐煤分布特点,开发新型干燥脱水技术,在源头降低煤的水分含量,实现煤的经济运输,提高电厂的发电效率.

  11. Recent Development in Chemical Depolymerization of Lignin: A Review

    Directory of Open Access Journals (Sweden)

    Hai Wang

    2013-01-01

    Full Text Available This article reviewed recent development of chemical depolymerization of lignins. There were five types of treatment discussed, including base-catalyzed, acid-catalyzed, metallic catalyzed, ionic liquids-assisted, and supercritical fluids-assisted lignin depolymerizations. The methods employed in this research were described, and the important results were marked. Generally, base-catalyzed and acid-catalyzed methods were straightforward, but the selectivity was low. The severe reaction conditions (high pressure, high temperature, and extreme pH resulted in requirement of specially designed reactors, which led to high costs of facility and handling. Ionic liquids, and supercritical fluids-assisted lignin depolymerizations had high selectivity, but the high costs of ionic liquids recycling and supercritical fluid facility limited their applications on commercial scale biomass treatment. Metallic catalyzed depolymerization had great advantages because of its high selectivity to certain monomeric compounds and much milder reaction condition than base-catalyzed or acid-catalyzed depolymerizations. It would be a great contribution to lignin conversion if appropriate catalysts were synthesized.

  12. Effect of oxydesulphurization on the combustion characteristics of coal

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Kucukbayrak, S. [Technical University of Istanbul, Istanbul (Turkey). Dept. of Chemical Engineering

    1997-06-01

    Desulphurization of a Turkish lignite by oxydesulphurization using dilute alkaline solutions, obtained by the extraction of fly ash with water, was carried out under 0-1.5 MPa partial pressure of oxygen at temperatures between 403 and 498 K for 30-90 min time intervals. The combustion characteristics of original and desulphurized lignite samples are compared using TGA. DTG curves were derived and the effects of desulphurization conditions such as temperature, partial pressure of oxygen and time on coal reactivity were studied. Ignition temperature, maximum combustion rate, combustion period, and the end temperature of combustion were considered. Relations between coal reactivity and removals of sulphur and ash contents were also studied.

  13. An overview of Turkish lignite qualities by logistic analysis

    Institute of Scientific and Technical Information of China (English)

    Bulent TUTMEZ; Burak HOZATLI; A.Kemal CENGIZ

    2013-01-01

    As an indispensable energy source,lignite is almost exclusively used in power generation in Turkey.To assess the quality level of Turkish lignite,a multivariate statistical analysis was conducted.The relationship among the lignite quality parameters has been investigated using a response method that is the logistic regression method.The analysis determines the effect of multiple predictor variables such as moisture,ash and sulphur presented simultaneously to predict membership of the two calorific value categories.By this way,a reliable binary response regression structure was constructed considering all the lignite fields in Turkey.Both the experiments on identifying the influential measurements and the measure of goodness of fit indicated that the overall model has a big capability to exhibit the relationship among the parameters of the Turkish lignite.

  14. Ultrasound assisted enzymatic depolymerization of aqueous guar gum solution.

    Science.gov (United States)

    Prajapat, Amrutlal L; Subhedar, Preeti B; Gogate, Parag R

    2016-03-01

    The present work investigates the effectiveness of application of low intensity ultrasonic irradiation for the intensification of enzymatic depolymerization of aqueous guar gum solution. The extent of depolymerization of guar gum has been analyzed in terms of intrinsic viscosity reduction. The effect of ultrasonic irradiation on the kinetic and thermodynamic parameters related to the enzyme activity as well as the intrinsic viscosity reduction of guar gum using enzymatic approach has been evaluated. The kinetic rate constant has been found to increase with an increase in the temperature and cellulase loading. It has been observed that application of ultrasound not only enhances the extent of depolymerization but also reduces the time of depolymerization as compared to conventional enzymatic degradation technique. In the presence of cellulase enzyme, the maximum extent of depolymerization of guar gum has been observed at 60 W of ultrasonic rated power and ultrasonic treatment time of 30 min. The effect of ultrasound on the kinetic and thermodynamic parameters as well as the molecular structure of cellulase enzyme was evaluated with the help of the chemical reaction kinetics model and fluorescence spectroscopy. Application of ultrasound resulted in a reduction in the thermodynamic parameters of activation energy (Ea), enthalpy (ΔH), entropy (ΔS) and free energy (ΔG) by 47%, 50%, 65% and 1.97%, respectively. The changes in the chemical structure of guar gum treated using ultrasound assisted enzymatic approach in comparison to the native guar gum were also characterized by FTIR. The results revealed that enzymatic depolymerization of guar gum resulted in a polysaccharide with low degree of polymerization, viscosity and consistency index without any change in the core chemical structure which could make it useful for incorporation in food products.

  15. Pyrolysis and co-pyrolysis of coal and oil shale

    Energy Technology Data Exchange (ETDEWEB)

    Qiumin Zhang; Demin He; Jun Guan [Dalian University of Technology, Dalian (China). Institute of Coal Chemical Engineering

    2007-07-01

    Pyrolysis and co-pyrolysis of coal and oil shale was investigated by using Yilan oil shale, Longkou oil shale, Huolinhe lignite, Taiji gas coal and Ruqigou anthracite as raw materia1s. A fixed-bed pyrolysis and co-pyrolysis of these coal and oil shale were investigated. The results indicated that synergetic effect existed with the oil yield increased, water yield decreased, and the synergetic effect varied with the mass percentage of coal differed. The co-pyrolysis oil yield of Yilan oil shale and Ruqigou anthracite is a little higher than the linear sum of their oil yield in the pyrolysis process. But for the co-pyrolysis of Taiji gas coal and Yilan oil shale, no significant change of the oil yield was found. Huolinhe lignite and Longkou oil shale were chosen as the material for the solid heat carrier experiment. Synergetic effect analyses of both the fixed-bed pyrolysis and the retorting process with solid heat carrier were given. Huolinhe lignite is an ideal material for oil recovery by pyrolysis, with high volatile and low ash, its oil content is 8.55%. Longkou oil shale is an ideal material for oil recovery by pyrolysis, with high oil content of 14.38%. The optimum co-pyrolysis temperature for Huolinhe lignite and Longkou oil shale is 510{sup o}C. Synergetic effect was found with the oil increased 9% and water decreased 36%. 5 refs., 2 figs., 10 tabs.

  16. Coal reserves of Republic of Sakha (Yakutia) and principal lines of their use

    Energy Technology Data Exchange (ETDEWEB)

    G.S. Golovin; M.I. Bychev; T.V. Moskalenko; G.I. Petrova; V.A. Mikheev [FGUP Institute for Fossil Fuels, Science-and-Technology Center for Integrated Processing of Solid Fossil Fuels, Moscow (Russian Federation)

    2007-04-15

    The Republic of Sakha (Yakutia) has the largest reserves of lignites and coals in the Far East owing to three coal basins - Southern Yakutia, Lena, and Zyryanskii - in the republican territory and the eastern part of the Tunguska basin. Main deposits, their resources, clay type composition, and lines of use are discussed.

  17. Slurry pumping techniques for feeding high-pressure coal gasification reactors

    Science.gov (United States)

    Bair, W. G.; Tarman, P. B.

    1977-01-01

    Operating experience in pumping coal and coal char slurries at pressures up to 1500 psig is discussed. The design specifications for the mixing tanks, pumps, piping, and slurry heaters are given along with pressure drop and minimum flow velocity data on water-lignite slurries.

  18. Development of Kinetics and Mathematical Models for High-Pressure Gasification of Lignite-Switchgrass Blends: Cooperative Research and Development Final Report, CRADA Number CRD-11-447

    Energy Technology Data Exchange (ETDEWEB)

    Iisa, Kristiina [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    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 in defining key reactive properties of mixed coal biomass fuels.

  19. Relationships proximate analysis results and higher heating values of lignites

    Energy Technology Data Exchange (ETDEWEB)

    Demirbas, A. [Sila Science, Trabzon (Turkey)

    2008-07-01

    In this study, the higher heating values (HHVs) of 26 lignite samples were calculated by using the proximate and elemental analyses data. The proximate analysis results such as volatile materials (VM), fixed carbon (FC) and HHV and the elemental analysis results such as carbon, hydrogen (H), oxygen (O), nitrogen (N) and sulfur (S) were determined for 26 lignite samples from different areas of Turkey. The lignite samples have been tested with particle size of 0-0.05 mm. The HHVs of 26 lignite samples obtained from different Turkish sources were determined experimentally and calculated from both ultimate and proximate analyses. HHVs of 26 the lignite samples can be calculated from the equation based modeling. The HHVs (MJ/kg) of the lignite samples as a function of fixed carbon (FC, wt%) or volatile materials (VM, %) was calculated from the following equations: HHV = 0.300FC + 11.117 (1) HHV = -0.323VM + 42.223 (2) where the correlation coefficients for Eqs. (1) and (2) were 0.9907 and 0.9862, respectively. The combustion heats calculated from Eqs. (1) and (2) showed mean differences of +3.9% and +0.3%, respectively. The HHVs (MJ/kg) of the lignite samples as a function of C, H, O, N, and S were calculated from a given equation where the correlation coefficients for the equation was 0.9891. HHVs calculated from this equation showed a mean deviation of +0.1.

  20. Drying grain using a hydrothermally treated liquid lignite fuel

    Energy Technology Data Exchange (ETDEWEB)

    Bukurov, Z.; Cvijanovic, P.; Bukurov, M. [Univ. of Novi Sad (Yugoslavia); Ljubicic, B.R. [Univ. of North Dakota, Grand Forks, ND (United States)

    1995-12-01

    A shortage of domestic oil and natural gas resources in Yugoslavia, particularly for agricultural and industrial purposes, has motivated the authors to explore the possibility of using liquid lignite as an alternate fuel for drying grain. This paper presents a technical and economic assessment of the possibility of retrofitting grain-drying plants currently fueled by oil or natural gas to liquid lignite fuel. All estimates are based on lignite taken from the Kovin deposit. Proposed technology includes underwater mining techniques, aqueous ash removal, hydrothermal processing, solids concentration, pipeline transport up to 120 km, and liquid lignite direct combustion. For the characterization of Kovin lignite, standard ASTM procedures were used: proximate, ultimate, ash, heating value, and Theological analyses were performed. Results from an extensive economic analysis indicate a delivered cost of US$20/ton for the liquid lignite. For the 70 of the grain-drying plants in the province of Vojvodina, this would mean a total yearly saving of about US $2,500,000. The advantages of this concept are obvious: easy to transport and store, nonflammable, nonexplosive, nontoxic, 30%-40% cheaper than imported oil and gas, domestic fuel is at hand. The authors believe that liquid lignite, rather than an alternative, is becoming more and more an imperative.

  1. The depolymerization of sodium alginate by oxidative degradation.

    Science.gov (United States)

    Mao, Shirui; Zhang, Tingting; Sun, Wei; Ren, Xuhong

    2012-01-01

    Alginate has been extensively used as a carrier for macromolecules and as gene delivery vehicle. Both properties are molecular weight (Mw) dependent. Herein, we investigated factors affecting the oxidative depolymerization of alginate. The depolymerization process occurred mainly in the first 1 h. The Mw of the depolymerized alginate was influenced by the reaction temperature. At temperature 20 and 30°C, Mw of the alginate fragment kept constant and further Mw decrease was observed at 40°C. Along with the increase of hydrogen peroxide concentration, the Mw of the fragments decreased gradually. Influence of alginate initial concentration was marginal. A linear decrease of Mw was observed when the system pH was in the range of 5-7, whereas no further change was found when the system pH decreased from 7 to 8. Fourier transformed infrared spectroscopy spectra revealed that degradation undergoes by the breakage of the glycosidic bonds of polymers. No structural change was observed during the depolymerization process by UV spectroscopy. Cloud point pH increase was found for alginate 30 k. In summary, this method is an effective and convenient approach for preparing low Mw oligosaccharides from sodium alginate and may be potentially useful for the drug delivery system design with alginate.

  2. Microtubule depolymerization induces traction force increase through two distinct pathways.

    Science.gov (United States)

    Rape, Andrew; Guo, Wei-hui; Wang, Yu-li

    2011-12-15

    Traction forces increase after microtubule depolymerization; however, the signaling mechanisms underlying this, in particular the dependence upon myosin II, remain unclear. We investigated the mechanism of traction force increase after nocodazole-induced microtubule depolymerization by applying traction force microscopy to cells cultured on micropatterned polyacrylamide hydrogels to obtain samples of homogeneous shape and size. Control cells and cells treated with a focal adhesion kinase (FAK) inhibitor showed similar increases in traction forces, indicating that the response is independent of FAK. Surprisingly, pharmacological inhibition of myosin II did not prevent the increase of residual traction forces upon nocodazole treatment. This increase was abolished upon pharmacological inhibition of FAK. These results suggest two distinct pathways for the regulation of traction forces. First, microtubule depolymerization activates a myosin-II-dependent mechanism through a FAK-independent pathway. Second, microtubule depolymerization also enhances traction forces through a myosin-II-independent, FAK-regulated pathway. Traction forces are therefore regulated by a complex network of complementary signals and force-generating mechanisms.

  3. Characterization of anaerobic consortia coupled lignin depolymerization with biomethane generation.

    Science.gov (United States)

    Wu, Yi-Rui; He, Jianzhong

    2013-07-01

    Two sediment-free microbial consortia (LI3 and LP3) were established to depolymerize lignin under anaerobic conditions. During depolymerizing high molecular weight lignin to low molecular weight molecules, the two cultures produced biomethane up to 151.7 and 113.0 mL g(-1) total lignin. Furthermore, LI3 and LP3 could also utilize the biomass - oil palm empty fruit bunch fiber (OPEFB) to produce 190.6 and 195.6 mL methaneg(-1) total lignin in OPEFB, and at the same time improve the bioavailability of lignocellulosic matters for further enzymatic hydrolysis. The microbial community analysis by denature gradient gel electrophoresis (DGGE) and the high-density 16S rDNA gene microarray (PhyloChip) exhibited that Methanomethylovorans sp. (LI3) and Methanoculleus sp. (LP3) were the main methanogens present, and phylum Firmicutes and Bacteroidetes were mainly involved in the lignin depolymerization. The established microbial consortia with both lignin depolymerization and biomethane production provide profound application on the environmental friendly pretreatment of lignocellulosic materials.

  4. An investigation of washability characteristics of lignites from Yenicubuk-Gemerek districts by MGS; Yenicubuk gemerek linyit komurlerinin MGS ile yikanabilirliginin arastirilmasi

    Energy Technology Data Exchange (ETDEWEB)

    Aslan, N.; Canbazoglu, M.; Ulusoy, U. [Cumhuriyet Universitesi, Sivas (Turkey). Maden Muhendisligi Bolumu

    1999-07-01

    Washability and ash removal from Gemerek lignite in a multi gravity separator (MGS) were investigated. Experimental studies were carried out on -0.5 mm coal samples containing 37.75% ash in a laboratory C-900 type MGS. Drum speed, shake amplitude, tilt angle, shake frequency, wash water quantity and feed solid ratio were investigated. Optimum operating conditions were determined. 8 refs., 7 figs.

  5. Differential sedimentation and selective flocculation in the desulfurization of Teruel lignite. Sedimentacion diferencial y floculacion selectiva en la desulfuracion de los lignitos de Teruel

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, R.; Clemente, C.; Gomez-Limon, D. (Escuela Tecnica Superior de Ingenieros de Minas de Madrid, Madrid (Spain))

    1988-01-01

    At the time of researching the possibility to remove the sulfur of the lignites located in the Teruel area via selective flocculation, it has been proved that in the case of the sulfur on its sulfur form, there's a pronounced interference with the differential sedimentation between coal and sulfur, increased by the fact of a selective liberation. This differential sedimentation shows better results on the sulfur removal process than that obtained by selective flocculation. 8 refs., 12 tabs.

  6. New colporate pollen taxa from Neyveli lignite, South India

    Energy Technology Data Exchange (ETDEWEB)

    Singh, A.; Misra, B.K. (Birbal Sahni Institute of Palaeobotany, Lucknow (India))

    1991-02-19

    Four new pollen genera: {ital Bacuspinulopollenites} {ital Cuddaloripollis}, {ital Scrobiculatricolporites}, {ital Tamilipollenites} and seven new species from the subsurface lignite samples of the Mine III area of the Neyveli Lignite Field are described. {ital Tricolporopilites} (Kar and Saxena) Kar 1985 is amended and three new species {ital T. uniformis}, {ital T. differentialis} and {ital T. tectatus} are assigned to it. These colporate angiospermous pollen taxa provide additional information on the palynofloral composition of the main lignite seam encountered in three boreholes. 19 refs., 5 figs.

  7. Effects of coal rank on the chemical composition and toxicological activity of coal liquefaction materials

    Energy Technology Data Exchange (ETDEWEB)

    Wright, C.W.; Dauble, D.D.

    1986-05-01

    This report presents data from the chemical analysis and toxicological testing of coal liquefaction materials from the EDS and H-Coal processes operated using different ranks of coal. Samples of recycle solvent from the bottoms recycle mode of the EDS direct coal liquefaction process derived from bituminous, sub-bituminous, and lignite coals were analyzed. In addition, the H-Coal heavy fuel oils derived from bituminous and sub-bituminous coals were analyzed. Chemical methods of analysis included adsoprtion column chromatography, high-resolution gas chromatography, gas chromatography/mass spectrometry, and low-voltage probe-inlet mass spectrometry. The toxicological activity of selected samples was evaluated using the standard microbial mutagenicity assay, an initiation/promotion assay for mouse-skin tumorigenicity, and a static bioassy with Daphnia magna for aquatic toxicity of the water-soluble fractions. 22 refs., 16 figs., 14 tabs.

  8. Prediction of SO{sub 2} and NOx emissions for low-grade Turkish lignites in CFB combustors

    Energy Technology Data Exchange (ETDEWEB)

    Gungor, A. [Nigde University, Nigde (Turkey). Dept. of Mechanical Engineering

    2009-02-15

    The CFB technology is widely used for combustion of coal because of its unique ability to handle low quality, high ash, high sulphur and low heating value coals. This paper presents a modeling study of pollutant emissions such as sulphur dioxide (SO{sub 2}) and nitric oxide (NOx) resulting from coal combustion in a CFBC. Using this model, overall SO{sub 2} and NOx emissions are predicted for the combustion of three different kinds of low-grade Turkish lignites. The contents of these lignites are as follows: ash from 23.70% to 45.31%, sulphur from 1.81% to 8.40% and calorific values (LHV) from 10,283 to 15.215 kJ/kg. The data is obtained from two pilot scale CFBCs (50 and 80 kW) and an industrial scale CFBC (160 MW). The present study proves that CFB combustion demonstrated by both experimental data and model predictions produces low and acceptable level of SO{sub 2} and NOx emissions resulting from the combustion of low-grade lignites. Developed model can also investigate the effects of different operational parameters on overall SO{sub 2} and NOx emissions. As a result of this investigation, it is observed that increase of excess air decreases SO{sub 2} and NOx emissions. However, NOx emission increases with the operational bed velocity while SO{sub 2} emission decreases. A bigger inlet bed pressure value results in lower emissions of SO{sub 2} and NOx if other parameters are kept unchanged.

  9. Model Research of Gas Emissions From Lignite and Biomass Co-Combustion in a Large Scale CFB Boiler

    Directory of Open Access Journals (Sweden)

    Krzywański Jarosław

    2014-06-01

    Full Text Available The paper is focused on the idea of a combustion modelling of a large-scale circulating fluidised bed boiler (CFB during coal and biomass co-combustion. Numerical computation results for three solid biomass fuels co-combustion with lignite are presented in the paper. The results of the calculation showed that in previously established kinetics equations for coal combustion, some reactions had to be modified as the combustion conditions changed with the fuel blend composition. Obtained CO2, CO, SO2 and NOx emissions are located in borders of ± 20% in the relationship to the experimental data. Experimental data was obtained for forest biomass, sunflower husk, willow and lignite cocombustion tests carried out on the atmospheric 261 MWe COMPACT CFB boiler operated in PGE Turow Power Station in Poland. The energy fraction of biomass in fuel blend was: 7%wt, 10%wt and 15%wt. The measured emissions of CO, SO2 and NOx (i.e. NO + NO2 were also shown in the paper. For all types of biomass added to the fuel blends the emission of the gaseous pollutants was lower than that for coal combustion.

  10. Short description of the Peruvian coal basins

    Energy Technology Data Exchange (ETDEWEB)

    Carrascal-Miranda, Eitel R. [UNI, Lima (Peru); Suarez-Ruiz, Isabel [Instituto Nacional del Carbon (CSIC), Ap. Co., 73, 33080 Oviedo (Spain)

    2004-04-23

    This work synthesizes the main general characteristics of the Peruvian Coal Basins in relation to age, coal facies and coal rank. Peruvian coals are located in a series of coal basins from the Paleozoic to the Cenozoic age. Paleozoic coal seams are mainly of Mississippian age (Carboniferous). They are of continental origin and their reduced thickness and ash content are their main characteristics. Mesozoic coal seams (Upper Jurassic-Lower Cretaceous) are located in the so-called Peruvian Western Basin and in the depressions close to the 'Maranon Geoanticline'. They were originated in deltaic facies under the influence of brackish and fresh waters. Some of these coal basins (those distributed in the central and northern parts of Peru) are relatively well known because they are of economic importance. Finally, Cenozoic coal seams (Tertiary) are found in both paralic and limnic basins and their reserves are limited. All the Peruvian coals are of humic character and are vitrinite-rich. Their rank is highly variable and normally related with the different orogenic events which strongly affected this region. Thus, Paleozoic and Mesozoic coals are of bituminous to anthracite/meta-anthracite coal rank while peats, lignite and subbituminous coals are found in Cenozoic basins.

  11. Comparative Study of Coal and Biomass Co-Combustion With Coal Burning Separately Through Emissions Analysis

    Directory of Open Access Journals (Sweden)

    Mohammad Siddique

    2016-06-01

    Full Text Available Appropriate eco-friendly methods to mitigate the problem of emissions from combustion of fossil fuel are highly demanded. The current study was focused on the effect of using coal & coal-biomass co-combustion on the gaseous emissions. Different biomass' were used along with coal. The coal used was lignite coal and the biomass' were tree waste, cow dung and banana tree leaves. Various ratios of coal and biomass were used to investigate the combustion behavior of coal-biomass blends and their emissions. The study revealed that the ratio of 80:20 of coal (lignite-cow dung and 100% banana tree leaves emits less emissions of CO, CO2, NOx and SO2 as compared to 100% coal. Maximum amount of CO emissions were 1510.5 ppm for banana tree waste and minimum amount obtained for lakhra coal and cow dung manure (70:30 of 684.667 ppm. Maximum percentage of SO2 (345.33 ppm was released from blend of lakhra coal and tree leaves (90:10 and minimum amount of SO2 present in samples is in lakhra coal-banana tree waste (80:20. The maximum amount of NO obtained for banana tree waste were 68 ppm whereas maximum amount of NOx was liberated from lakhra coal-tree leaves (60:40 and minimum amount from cow dung manure (30.83 ppm. The study concludes that utilization of biomass with coal could make remedial action against environment pollution.

  12. Trace elements partitioning during co-firing biomass with lignite in a pilot-scale fluidized bed combustor

    Energy Technology Data Exchange (ETDEWEB)

    Gogebakan, Zuhal [Department of Chemical Engineering, Middle East Technical University, 06531 Ankara (Turkey)], E-mail: zuhalgogebakan@hotmail.com; Selcuk, Nevin [Department of Chemical Engineering, Middle East Technical University, 06531 Ankara (Turkey)], E-mail: selcuk@metu.edu.tr

    2009-03-15

    This study describes the partitioning of 18 trace elements (As, Ba, Cd, Co, Cr, Cu, Li, Mn, Mo, Ni, P, Pb, Sb, Se, Sn, Tl, V, Zn) and 9 major and minor elements (Al, Ca, Fe, K, Mg, Na, S, Si, Ti) during co-firing of olive residue, hazelnut shell and cotton residue with high sulfur and ash content lignite in 0.3 MW{sub t} Middle East Technical University (METU) Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) test rig with limestone addition. Concentrations of trace elements in coal, biomass, limestone, bottom ash, cyclone ash and filter ash were determined by inductively coupled plasma optical emission and mass spectroscopy (ICP-OES and ICP-MS). Partitioning of major and minor elements are influenced by the ash split between the bottom ash and fly ash and that the major proportion of most of the trace elements (As, Ba, Co, Cr, Cu, Li, Mn, Mo, Ni, Pb, Tl, V and Zn) are recovered in fly ash when firing lignite only. Co-firing lignite with biomass enhances partitioning of these elements to fly ash. Co-firing also shifts the partitioning of Cd, P, Sb and Sn from bottom to fly ash.

  13. Biosolubilization of lignite by marine soil microbes

    Energy Technology Data Exchange (ETDEWEB)

    Murugesh, S.; Manivannan, S.; Mahesh, N.; Mohanasrinivasan, V.; Devi, V.S. [Deemed University, Thanjavur (India). School of Chemical and Biotechnology

    2003-07-01

    Mangrove forest soil samples were collected from different locations. Before starting the experiment, soil pH and EC are analysed. The medium used for cultivation of fungi is Czapek Dox broth. Two different methods are used for extraction of humic acid from fungi culture medium, such as the shakeflask method and the respirometer method. Results from the microbial status production of biosolubilized product humic-acid fungi gives a high amount compared to bacteria and actinomycetes. Hence fungi gave the best result for biosolubilization of lignite to humic acid. In addition to microbial status, physico-chemical parameters, such as nitrogen, phosphorus, potassium, sodium, and organic carbon of soil were also analyzed. 12 refs., 1 fig., 11 tabs.

  14. Geochemistry of Kasnau-Matasukh lignites, Nagaur Basin,Rajasthan (India)

    Institute of Scientific and Technical Information of China (English)

    Prakash K.Singh; Pramod K.Rajak; Mahendra P.Singh; Vijay K.Singh; Amiya S.Naik

    2016-01-01

    The distribution and verticals variation of geochemical components in the Kasnau-Matasukh lignites of Nagaur Basin,Rajasthan,were investigated using microscopy,proximate and ultimate analyses,Rock-Eval Pyrolysis,X-ray diffraction and Fourier Transform Infrared analyses,and major/minor/trace element determination.The relationship of elements with ash content and with macerals have also been discussed.These lignites are stratified,black,dominantly composed of huminite group macerals with subordinated amounts of liptinite and inertinite groups.They are classified as type-Ⅲ kerogen and are mainly gas prone in nature.The concentration (in vol%) of mineral matter is seen to increase towards upper part of seam and so is the concentration (in wt%) of the volatile matter,elemental carbon and sulphur.The common minerals present in these lignitesare mixed clay layer,chlorite,and quartz as identified by X-ray diffraction study.Compared with world average in brown coal,the bulk concentration of Cu is anomalously high in most of the samples while Cd is 2-3 times high and Zn is high in one band.Based on interrelationship,different pyrite forms are noticed to have different preferential enrichment of various elements.The concentration of disseminated pyrite is more than the other pyrite forms and is followed by discrete pyrite grains and massive pyrite.

  15. Hydrologic and geochemical data for the Big Brown Lignite Mine area, Freestone County, Texas

    Energy Technology Data Exchange (ETDEWEB)

    Dorsey, M.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. One of the potential hydrologic effects of surface coal mining is a change in the quality of groundwater 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 paste-extract 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 mg/L. Water from selected wells contains dissolved solids concentrations ranging from 75 to 510 mg/L. 10 refs., 3 figs., 8 tabs.

  16. Evaluation of lignite combustion residues as cement additives

    Energy Technology Data Exchange (ETDEWEB)

    Demirbas, A.; Aslan, A.

    1999-07-01

    In this study the physical and chemical properties of lignite fly ashes obtained from electrostatic precipitator and cyclone, lignite bottom ash, cement + lignite ash mixtures, and their effects on mechanical properties of concrete were investigated. The ashes were classified into two general types based on total silica, alumina, and iron-III oxide: class A and class B. When 25% of the cement was replaced by class A lignite bottom ash (the combined three oxide contents were 30.2%), the 28-day compressive strength increased by 18.9% compared to the control mix, and when 25% of the cement was replaced by class B lignite ash (the combined three oxide contents were 78.1%), the compressive strength decreased by 3.5% compared to the control mix. The results obtained were compared with the Turkish Standards and, in general, were found to be within the limits. As a result, the lignite fly ash and bottom ash samples may be used as cementitious materials.

  17. Coal Seams in the Horna Nitra Valley – the Cigel Mining Area

    Directory of Open Access Journals (Sweden)

    Jozef Fazekaš

    2009-09-01

    Full Text Available According to the statistics data, coal will become with no doubt the most important energy source in the 21-st century. The HornaNitra Valley represents one of the main fuels – energy centre of Slovakia. Deposits of caustobioliths – brown coal and lignite presentsignificant raw material potential. The mining companies, along with run-in extraction methods of coal reserves, are giving their timeto a research of untraditional coal processing technologies. An in-situ monitoring of coal seams geo-technological propertiescontributes in a significant way to obtain some complex knowledge on interactions of certain determining factors which influencethe coal gases formation underground.

  18. Coal geology of the Paleocene-Eocene Calvert Bluff Formation (Wilcox Group) and the Eocene Manning Formation (Jackson Group) in east-central Texas; field trip guidebook for the Society for Organic Petrology, Twelfth Annual Meeting, The Woodlands, Texas, August 30, 1995

    Science.gov (United States)

    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.

  19. A possible link between Balkan endemic nephropathy and the leaching of toxic organic compounds from Pliocene lignite by groundwater: Preliminary investigation

    Science.gov (United States)

    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

  20. Large-Scale Mercury Control Technology Testing for Lignite-Fired Utilities - Oxidation Systems for Wet FGD

    Energy Technology Data Exchange (ETDEWEB)

    Steven A. Benson; Michael J. Holmes; Donald P. McCollor; Jill M. Mackenzie; Charlene R. Crocker; Lingbu Kong; Kevin C. Galbreath

    2007-03-31

    Mercury (Hg) control technologies were evaluated at Minnkota Power Cooperative's Milton R. Young (MRY) Station Unit 2, a 450-MW lignite-fired cyclone unit near Center, North Dakota, and TXU Energy's Monticello Steam Electric Station (MoSES) Unit 3, a 793-MW lignite--Powder River Basin (PRB) subbituminous coal-fired unit near Mt. Pleasant, Texas. A cold-side electrostatic precipitator (ESP) and wet flue gas desulfurization (FGD) scrubber are used at MRY and MoSES for controlling particulate and sulfur dioxide (SO{sub 2}) emissions, respectively. Several approaches for significantly and cost-effectively oxidizing elemental mercury (Hg{sup 0}) in lignite combustion flue gases, followed by capture in an ESP and/or FGD scrubber were evaluated. The project team involved in performing the technical aspects of the project included Babcock & Wilcox, the Energy & Environmental Research Center (EERC), the Electric Power Research Institute, and URS Corporation. Calcium bromide (CaBr{sub 2}), calcium chloride (CaCl{sub 2}), magnesium chloride (MgCl{sub 2}), and a proprietary sorbent enhancement additive (SEA), hereafter referred to as SEA2, were added to the lignite feeds to enhance Hg capture in the ESP and/or wet FGD. In addition, powdered activated carbon (PAC) was injected upstream of the ESP at MRY Unit 2. The work involved establishing Hg concentrations and removal rates across existing ESP and FGD units, determining costs associated with a given Hg removal efficiency, quantifying the balance-of-plant impacts of the control technologies, and facilitating technology commercialization. The primary project goal was to achieve ESP-FGD Hg removal efficiencies of {ge}55% at MRY and MoSES for about a month.

  1. Effect of application rate of commercial lignite-derived amendments on early-stage growth of Medicago sativa and soil health, in acidic soil conditions

    Science.gov (United States)

    Patti, Antonio; Little, Karen; Rose, Michael; Jackson, Roy; Cavagnaro, Tim

    2013-04-01

    Commercially available lignite-derived amendments, sold mainly as humate preparations, have been promoted as plant growth stimulants leading to higher crop yields. These products are also claimed to improve soil properties such as pH. This study investigated the effect of application rate of three lignite-derived amendments on the early-stage growth of a pasture legume, lucerne (Medicago sativa), and soil health in a soil type common to south eastern Australia, in a glasshouse setting. An organic-mineral humate product and 'run of mine' lignite coal did not improve shoot or root growth despite application at a range of rates at, and in excess of, the manufacturers recommendation. Application of soluble K-humate product at 20 kg/ha (9.5 kg/ha C equivalent) produced an observable positive effect in shoot growth. At this application rate, a significant delay in the appearance of chlorotic symptoms was observed along with an increase in soil pH concurrent with decreased availability of soil Mn and Al. Higher root dry weight was associated with lower microbial biomass carbon which may indicate an effect on allocation of resources between the microbial community and the plant. An assessment of the effectiveness of lignite-derived amendments on plant growth, as well as their potential to improve the health of an acidic soil will assist farmers in making decisions regarding the use of these products.

  2. The relation between the lithotypes of Pliocene coals from Oltenia and their main quality characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Ticleanu, N.; Scradeanu, D.; Popa, M.; Milutinovici, S.; Popa, R.; Preda, I.; Ticleanu, M.; Savu, C.; Diaconita, D.; Barus, T.; Petrescu, I.; Dinulescu, C.; Maftei, R. [University of Bucharest, Bucharest (Romania). Faculty of Geology and Geophysics

    1999-11-01

    The main Pliocene lignite lithotypes from Oltenia (detrital coal, xylite, xylite coal, weakly xylite coal, clayey coal) were formed within various coal facies named after the dominant paleophytocoenoses: the forest with Sequoia, the grassy swamp (Carex ssp.), the deciduous forest swamp, the forest swamp with Glyptostrobus, the marsh with Phragmites and the aquatic plants prairie. In each of these coals facies 1-3 lignite lithotypes were formed. Due to the fact that the chemistry of the parental vegetal material was different with regards to each community and that this parental vegetal material was accumulated within different environmental conditions, the resultant lithotypes present specific properties. This paper concentrates on ash, hygroscopic moisture, volatile matter, calorific value and combustible sulfur. Moreover, the main characteristics of the xylite lithotype are analysed. Xylite, by its properties (primary carbonificiation products, benzene-alcohol extract, pore structure, carbon content, etc.) represents a valuable lithotype as a prime matter source. 19 refs., 5 figs., 4 tabs.

  3. The relation between the lithotypes of Pliocene coals from Oltenia and their main quality characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Ticleanu, N.; Scradeanu, D.; Popa, M.; Milutinovici, S.; Popa, R.; Preda, I.; Ticleanu, M.; Savu, C.; Diaconita, D.; Barus, T.; Petrescu, I.; Dinulescu, C.; Maftei, R. (University of Bucharest, Bucharest (Romania). Faculty of Geology and Geophysics)

    1999-01-01

    The main Pliocene lignite lithotypes from Oltenia (detrital coal, xylite, xylite coal, weakly xylite coal, clayey coal) were formed within various coal facies named after the dominant paleophytocoenoses: the forest with Sequoia, the grassy swamp (Carex ssp.), the deciduous forest swamp, the forest swamp with Glyptostrobus, the marsh with Phragmites and the aquatic plants prairie. In each of these coals facies 1-3 lignite lithotypes were formed. Due to the fact that the chemistry of the parental vegetal material was different with regards to each community and that this parental vegetal material was accumulated within different environmental conditions, the resultant lithotypes present specific properties. This paper concentrates on ash, hygroscopic moisture, volatile matter, calorific value and combustible sulfur. Moreover, the main characteristics of the xylite lithotype are analysed. Xylite, by its properties (primary carbonificiation products, benzene-alcohol extract, pore structure, carbon content, etc.) represents a valuable lithotype as a prime matter source. 19 refs., 5 figs., 4 tabs.

  4. Study of ion beam induced depolymerization using positron annihilation techniques

    Energy Technology Data Exchange (ETDEWEB)

    Puglisi, O. E-mail: opuglisi@dipchi.unict.it; Fragala, M.E.; Lynn, K.G.; Petkov, M.; Weber, M.; Somoza, A.; Dupasquier, A.; Quasso, F

    2001-04-01

    Ion beam induced depolymerization of polymers is a special class of ion beam induced chemical reaction which gives rise to catastrophic 'unzipping' of macromolecules with production of large amounts of the monomer, of the order of many hundreds monomer molecules per each macromolecule. The possible modification of the density at microscopic level prompted us to undertake a study of this effect utilizing positron annihilation techniques in Poly(methylmethacrylate) (PMMA) before and after bombardment with He{sup +} 300 keV ions at 200 deg. C. Preliminary results shown here indicate that before bombardment there is a reproducible dependence of nano-hole distribution on the sample history. Moreover at 200 deg. C we do not detect formation of new cavities as a consequence of the strong depolymerization that occurs under the ion beam. The possible correlation of these findings with transport properties of PMMA at temperature higher than the glass transition temperature will be discussed.

  5. Formaldehyde stabilization facilitates lignin monomer production during biomass depolymerization.

    Science.gov (United States)

    Shuai, Li; Amiri, Masoud Talebi; Questell-Santiago, Ydna M; Héroguel, Florent; Li, Yanding; Kim, Hoon; Meilan, Richard; Chapple, Clint; Ralph, John; Luterbacher, Jeremy S

    2016-10-21

    Practical, high-yield lignin depolymerization methods could greatly increase biorefinery productivity and profitability. However, development of these methods is limited by the presence of interunit carbon-carbon bonds within native lignin, and further by formation of such linkages during lignin extraction. We report that adding formaldehyde during biomass pretreatment produces a soluble lignin fraction that can be converted to guaiacyl and syringyl monomers at near theoretical yields during subsequent hydrogenolysis (47 mole % of Klason lignin for beech and 78 mole % for a high-syringyl transgenic poplar). These yields were three to seven times those obtained without formaldehyde, which prevented lignin condensation by forming 1,3-dioxane structures with lignin side-chain hydroxyl groups. By depolymerizing cellulose, hemicelluloses, and lignin separately, monomer yields were between 76 and 90 mole % for these three major biomass fractions. Copyright © 2016, American Association for the Advancement of Science.

  6. Polar polycyclic aromatic compounds from different coal types show varying mutagenic potential, EROD induction and bioavailability depending on coal rank.

    Science.gov (United States)

    Meyer, Wiebke; Seiler, Thomas-Benjamin; Schwarzbauer, Jan; Püttmann, Wilhelm; Hollert, Henner; Achten, Christine

    2014-10-01

    Investigations of the bioavailability and toxicity of polycyclic aromatic compounds (PAC) have rarely considered the heterogeneity of coals and the impact of more polar PAC besides polycyclic aromatic hydrocarbons (PAH). Earlier, we investigated the toxicity of eight heterogeneous coals and their extracts. In the present study, the hazard potential with respect to mechanism-specific toxicity of polar fractions of dichloromethane extracts from coals was studied. Polar extract fractions of all coal types except for anthracite induced EROD activity (determined in RTL-W1 cells), independent of coal type (Bio-TEQs between 23 ± 16 and 52 ± 22 ng/g). The polar fractions of all bituminous coal extracts revealed mutagenic activity (determined using the Ames Fluctuation test). No significant mutation induction was detected for the polar extract fractions from the lignite, sub-bituminous coal and anthracite samples, which indicates a higher dependency on coal type for polar PAC here. Additionally, information on bioavailability was derived from a bioaccumulation test using the deposit-feeding oligochaete Lumbriculus variegatus which was exposed for 28 days to ground coal samples. Despite the high toxic potential of most coal extracts and a reduced biomass of Lumbriculus in bituminous coal samples, bioaccumulation of PAH and mortality after 28 days were found to be low. Limited bioaccumulation of PAH (up to 3.6 ± 3.8 mg/kg EPA-PAH) and polar PAC were observed for all coal samples. A significant reduction of Lumbriculus biomass was observed in the treatments containing bituminous coals (from 0.019 ± 0.004 g to 0.046 ± 0.011 g compared to 0.080 ± 0.025 g per replicate in control treatments). We conclude that bioavailability of native PAC from coals including polar PAC is low for all investigated coal types. In comparison to lignite, sub-bituminous coals and anthracite, the bioavailability of PAC from bituminous coals is slightly increased.

  7. Ion exchange properties of Wyodak premium coal samples

    Energy Technology Data Exchange (ETDEWEB)

    Vorres, K.S.

    1993-08-23

    Low rank coals (lignite and subbituminous) contain exchangeable cations. A sample of {minus}20+200 mesh Argonne Premium Wyodak coal was washed with nitric acid in a burette fitted with a coarse glass frit at the base of the graduations to remove the exchangeable cations from the system. The eluent was passed to a flow-through pH electrode and a titration curve was obtained on a computer file. A series of electrodes (pH, calcium, sodium and potassium) were used in separate experiments to follow the elution from the coal. Some implications for coal structure are also indicated.

  8. Environmental policy instruments towards lignite-fired power plants in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    A proposition is made that Turkey considers a pilot emission trading system for SO{sub 2}, Nox and/or PM emissions from its coal and lignite fired power plant in the efforts to comply with the EU Integrated Pollution Prevention Control (IPPC), the Large Combustion Plant (LCP) and the National Emissions Ceiling (NEC) Directives. Model calculations indicate that this could yield substantial cost savings compared to a traditional command and control approach. However, requirements in the IPPC Directive would be a major obstacle against emissions trading. The Turkish emission permitting system needs a major overhaul, including improving monitoring and enforcement practices to comply with the directives and to be able to implement and operate an emission trading system.

  9. Depolymerization-driven flow and the crawling of nematode sperm

    Science.gov (United States)

    Wolgemuth, Charles

    2008-03-01

    Cell crawling motility is integral in many biological and biomedical processes, such as wound healing, cancer metastasis, and morphogenesis. A complete understanding of the mechanisms by which cells crawl is still lacking, but it is known to entail at least three separate physical processes: (i) cytoskeletal extension at the front of the cell; (ii) adhesion to the substrate at the cell front and release at the rear; and (iii) advance of the cell body. In most cells, the cytoskeletal network is composed of actin. The mechanism by which force is generated to drive translocation of the cell body is still debated. Originally, this force was attributed to an actomyosin system similar to muscle. However, nematode sperm utilize a cytoskeleton composed of a network of Major Sperm Protein (MSP) that forms non-polar filaments for which molecular motors have not been identified. The motility of these cells still exhibits all three fundamental processes required for standard crawling motility. Experiments suggest that depolymerization of the cytoskeletal network is the force-producing mechanism for pulling up the rear. In this talk I will present a mechanical model that describes how depolymerization of the cytoskeleton can drive motility. This model accounts for both cytoskeletal displacements and cytsolic (the fluid component of the cell) flow. The model accurately fits in vitro data using nematode sperm extracts where depolymerization induces contraction of MSP polymer bundles. Application of this model to cell crawling produces testable predictions about how the size and shape of a cell affect crawling speed. Experiments using Caenorhabditis elegans sperm show good agreement with the model predictions. Interestingly, the model requires that cells are anisotropically elastic, being more stiff in the direction of motion than perpendicular to it. A simple physical picture can account for this anisotropy. The model also predicts that cell speed increases with anisotropy and

  10. [Depolymerization of chitosan by chinolytic complex from Bacillus sp. 739].

    Science.gov (United States)

    Il'ina, A V; Varlamov, V P; Melent'ev, A I; Aktuganov, G E

    2001-01-01

    Low-molecular-weight (3-6 kDa) water-soluble chitosan was obtained by enzymatic depolymerization. Hydrolysis of crab chitosan was induced by O-glycoside hydrolase (EC 3.2.1), an extracellular chitinolytic complex from Bacillus sp. 739. The optimum conditions for hydrolysis were found (sodium-acetate buffer, pH 5.2; 55 degrees C; an enzyme/substrate ratio 4 U/g chitosan; 1 h).

  11. Formic-acid-induced depolymerization of oxidized lignin to aromatics.

    Science.gov (United States)

    Rahimi, Alireza; Ulbrich, Arne; Coon, Joshua J; Stahl, Shannon S

    2014-11-13

    Lignin is a heterogeneous aromatic biopolymer that accounts for nearly 30% of the organic carbon on Earth and is one of the few renewable sources of aromatic chemicals. As the most recalcitrant of the three components of lignocellulosic biomass (cellulose, hemicellulose and lignin), lignin has been treated as a waste product in the pulp and paper industry, where it is burned to supply energy and recover pulping chemicals in the operation of paper mills. Extraction of higher value from lignin is increasingly recognized as being crucial to the economic viability of integrated biorefineries. Depolymerization is an important starting point for many lignin valorization strategies, because it could generate valuable aromatic chemicals and/or provide a source of low-molecular-mass feedstocks suitable for downstream processing. Commercial precedents show that certain types of lignin (lignosulphonates) may be converted into vanillin and other marketable products, but new technologies are needed to enhance the lignin value chain. The complex, irregular structure of lignin complicates chemical conversion efforts, and known depolymerization methods typically afford ill-defined products in low yields (that is, less than 10-20wt%). Here we describe a method for the depolymerization of oxidized lignin under mild conditions in aqueous formic acid that results in more than 60wt% yield of low-molecular-mass aromatics. We present the discovery of this facile C-O cleavage method, its application to aspen lignin depolymerization, and mechanistic insights into the reaction. The broader implications of these results for lignin conversion and biomass refining are also considered.

  12. Formic-acid-induced depolymerization of oxidized lignin to aromatics

    Science.gov (United States)

    Rahimi, Alireza; Ulbrich, Arne; Coon, Joshua J.; Stahl, Shannon S.

    2014-11-01

    Lignin is a heterogeneous aromatic biopolymer that accounts for nearly 30% of the organic carbon on Earth and is one of the few renewable sources of aromatic chemicals. As the most recalcitrant of the three components of lignocellulosic biomass (cellulose, hemicellulose and lignin), lignin has been treated as a waste product in the pulp and paper industry, where it is burned to supply energy and recover pulping chemicals in the operation of paper mills. Extraction of higher value from lignin is increasingly recognized as being crucial to the economic viability of integrated biorefineries. Depolymerization is an important starting point for many lignin valorization strategies, because it could generate valuable aromatic chemicals and/or provide a source of low-molecular-mass feedstocks suitable for downstream processing. Commercial precedents show that certain types of lignin (lignosulphonates) may be converted into vanillin and other marketable products, but new technologies are needed to enhance the lignin value chain. The complex, irregular structure of lignin complicates chemical conversion efforts, and known depolymerization methods typically afford ill-defined products in low yields (that is, less than 10-20wt%). Here we describe a method for the depolymerization of oxidized lignin under mild conditions in aqueous formic acid that results in more than 60wt% yield of low-molecular-mass aromatics. We present the discovery of this facile C-O cleavage method, its application to aspen lignin depolymerization, and mechanistic insights into the reaction. The broader implications of these results for lignin conversion and biomass refining are also considered.

  13. Comprehensive Fractal Description of Porosity of Coal of Different Ranks

    Directory of Open Access Journals (Sweden)

    Jiangang Ren

    2014-01-01

    Full Text Available 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.

  14. Comprehensive fractal description of porosity of coal of different ranks.

    Science.gov (United States)

    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.

  15. Development of Energy Efficient Technologies for Burning Coal in Modern Thermal Power Plants and Efficiency Assessment Tools

    Directory of Open Access Journals (Sweden)

    Dubrovskiy Vitali

    2016-01-01

    Full Text Available Universal ecological energy-efficient burner was described. The burner allows to burn different types of coal and lignite without the use of fuel oil for kindling the boiler. Efficiency assessment tools of the introduction of the burner for combustion of coal in modern thermal power plants were given.

  16. Development of Energy Efficient Technologies for Burning Coal in Modern Thermal Power Plants and Efficiency Assessment Tools

    Science.gov (United States)

    Dubrovskiy, Vitali; Zubova, Marina; Sedelnikov, Nikolai; Dihnova, Anna

    2016-02-01

    Universal ecological energy-efficient burner was described. The burner allows to burn different types of coal and lignite without the use of fuel oil for kindling the boiler. Efficiency assessment tools of the introduction of the burner for combustion of coal in modern thermal power plants were given.

  17. Depositional conditions of the coal-bearing Hirka Formation beneath late Miocene explosive volcanic products in NW central Anatolia, Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Sener, M. [Nigde University, Nigde (Turkey). Dept. of Geology

    2007-04-15

    This work focuses on the relationship between the coal deposition and explosive volcanism of the Miocene basin, NW central Anatolia, Turkey. The coal-bearing Hirka Formation was deposited over the Galatian Andesitic Complex and/or massive lagoonal environments during the Miocene. The investigated lignite is a high ash (from 32 to 58%) and sulphur (from 1.43 to 3.03%) lignite which is petrographically characterised by a high humunite content. The mineral matter of the studied lignite samples is made up of mainly clay minerals (illite-smectite and kaolinite), plagioclase and quartz in Bolu coal field, clay minerals (illite-smectite, smectite and illite), quartz, calcite, plagioclase and gypsum in Seben coal field, quartz, K-feldspar, plagioclase and clay minerals (kaolinite and illite) in Kibriscik, and dolomite, quartz, clinoptilolite, opal CT and gypsum in Camhdere coal field. The differences in these four types of lignite with specific mineralogical patterns may be due to the explosive volcanic events and depositional conditions which changed from one coal field to the others. There is a zonation from SW to SE in the studied area for zeolites. Carbonate minerals are commonly calcite in Seben and Kibriscik coal fields. In Bolu, coal samples are devoid of calcite and dolomite. These analyses show that there is an increase in the amount of Mg and a decrease in the amount of Na from the northwestern part to the southern part in the study area.

  18. Filament depolymerization can pull a chromosome during bacterial mitosis

    Science.gov (United States)

    Banigan, Edward; Gelbart, Michael; Gitai, Zemer; Liu, Andrea; Wingreen, Ned

    2011-03-01

    Chromosome segregation is fundamental to all cells, but the force-generating mechanisms underlying chromosome translocation in bacteria remain mysterious. Caulobacter crescentus utilizes a depolymerization-driven process in which a ParA protein structure elongates from the new cell pole and binds to a ParB-decorated chromosome, and then retracts via disassembly, thus pulling the chromosome across the cell. This poses the question of how a depolymerizing structure can robustly pull the chromosome that is disassembling it. We perform Brownian dynamics simulations with a simple and physically consistent model of the ParABS system. The simulations suggest that the mechanism of translocation is ``self-diffusiophoretic'': by disassembling ParA, ParB generates a ParA concentration gradient so that the concentration of ParA is higher in front of the chromosome than behind it. Since the chromosome is attracted to ParA via ParB, it moves up the ParA gradient and across the cell. We find that translocation is controlled by the product of an effective relaxation time for the chromosome and the rate of ParA disassembly. Our results provide a physical explanation of the mechanism of depolymerization-driven translocation and suggest physical explanations for recent experimental observations.

  19. Studies on the solubilization of German coal by fungi

    Energy Technology Data Exchange (ETDEWEB)

    Reiss, J. (Grahamhaus Stadt kg, Bad Kreuznach (Germany))

    1992-09-01

    The capability of seven basidiomycetes (Trametes versicolor, Poria placenta, Pleurotus florida, P. ostreatus, P. sajor-caju, P. eryngii, Stropharia sp.), one ascomycete (Chaetomium globosum) and five hyphomycetes and moulds (Humicola grisea, Trichoderma viride, Aspergillus terreus, Paecilomyces varioti, Papulaspora immersa) to solubilize medium and high volatile bituminous coals (types A and B) as well as four types of lignite B from Germany was tested in surface cultures. The intensity of bioliquefaction was determined by estimating the rate of droplet formation and by measuring the loss of weight of the coal granules gravimetrically. The bituminous coals with a relative high degree of coalification were only moderately converted by Trametes versicolor, Pleurotus florida, P. ostreatus and P. sajor-caju. The three species of Pleurotus caused the greatest rate of biosolubilization of lignite, yielding a loss of weight of the coal granules of more than 5.8% with a maximum of 7.6% with P. florida. The non-basidiomycetes proved to be less active with a liquefaction rate of up to 3.5% with Trichoderma viride. In general, the geologically younger lignite coals were more effectively solubilized than the older hard coals. The volatile matter and the oxygen content proved to be the principal factors influencing the intensity of bioconversion.

  20. An overview of lithotype associations of Miocene lignite seams exploited in Poland

    Science.gov (United States)

    Widera, Marek

    2016-09-01

    Currently, three stratigraphically distinct lignite seams of Early to Middle Miocene age are exploited in Poland, namely the third Ścinawa lignite seam (ŚLS-3), the second Lusatian lignite seam (LLS-2) and the first Mid-Polish lignite seam (MPLS-1). All of these are composed of numerous macroscopically distinguishable layers defined as lignite lithotypes. In the present paper, the lithotypes of Polish lignites are grouped into seven major lithotype associations that originated in various types of mire. Therefore, an approximate reconstruction of mire type can be based on lignite lithotypes. Within the Polish lignite seams examined, the commonest in order of importance are: xylodetritic (XDL), detroxylitic (DXL), detritic (DL) and xylitic (XL) lithotype associations, mostly with a massive (m) or horizontal (h) structure. They are particularly dominant in lignite opencasts belonging to the Konin and Adamów mines. However, in the lowermost seams at the Turów and Bełchatów mines, a substantial part of the seams comprises the bitumen-rich (BL) lithotype association. These seams also lignite lithotypes that in large quantities have a gelified (g) and/or nodular (n) structure. In contrast, lignites from the Sieniawa mine are characterised by an admixture of the best-developed lithotype associations of both fusitic (FL) and weathered (WL) lignites. Moreover, the vast majority of these lignites have a folded (fo) and/or faulted (fa) structure, because they were completely deformed by glaciotectonics.

  1. An overview of lithotype associations of Miocene lignite seams exploited in Poland

    Directory of Open Access Journals (Sweden)

    Widera Marek

    2016-09-01

    Full Text Available Currently, three stratigraphically distinct lignite seams of Early to Middle Miocene age are exploited in Poland, namely the third Ścinawa lignite seam (ŚLS-3, the second Lusatian lignite seam (LLS-2 and the first Mid-Polish lignite seam (MPLS-1. All of these are composed of numerous macroscopically distinguishable layers defined as lignite lithotypes. In the present paper, the lithotypes of Polish lignites are grouped into seven major lithotype associations that originated in various types of mire. Therefore, an approximate reconstruction of mire type can be based on lignite lithotypes. Within the Polish lignite seams examined, the commonest in order of importance are: xylodetritic (XDL, detroxylitic (DXL, detritic (DL and xylitic (XL lithotype associations, mostly with a massive (m or horizontal (h structure. They are particularly dominant in lignite opencasts belonging to the Konin and Adamów mines. However, in the lowermost seams at the Turów and Bełchatów mines, a substantial part of the seams comprises the bitumen-rich (BL lithotype association. These seams also lignite lithotypes that in large quantities have a gelified (g and/or nodular (n structure. In contrast, lignites from the Sieniawa mine are characterised by an admixture of the best-developed lithotype associations of both fusitic (FL and weathered (WL lignites. Moreover, the vast majority of these lignites have a folded (fo and/or faulted (fa structure, because they were completely deformed by glaciotectonics.

  2. Chemometric Study of the Ex Situ Underground Coal Gasification Wastewater Experimental Data.

    Science.gov (United States)

    Smoliński, Adam; Stańczyk, Krzysztof; Kapusta, Krzysztof; Howaniec, Natalia

    2012-11-01

    The main goal of the study was the analysis of the parameters of wastewater generated during the ex situ underground coal gasification (UCG) experiments on lignite from Belchatow, and hard coal from Ziemowit and Bobrek coal mines, simulated in the ex situ reactor. The UCG wastewater may pose a potential threat to the groundwater since it contains high concentrations of inorganic (i.e., ammonia nitrogen, nitrites, chlorides, free and bound cyanides, sulfates and trace elements: As, B, Cr, Zn, Al, Cd, Co, Mn, Cu, Mo, Ni, Pb, Hg, Se, Ti, Fe) and organic (i.e., phenolics, benzene and their alkyl derivatives, and polycyclic aromatic hydrocarbons) contaminants. The principal component analysis and hierarchical clustering analysis enabled to effectively explore the similarities and dissimilarities between the samples generated in lignite and hard coal oxygen gasification process in terms of the amounts and concentrations of particular components. The total amount of wastewater produced in lignite gasification process was higher than the amount generated in hard coal gasification experiments. The lignite gasification wastewater was also characterized by the highest contents of acenaphthene, phenanthrene, anthracene, fluoranthene, and pyrene, whereas hard coal gasification wastewater was characterized by relatively higher concentrations of nitrites, As, Cr, Cu, benzene, toluene, xylene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, and benzo(a)pyrene.

  3. Formation and retention of methane in coal. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hucka, V.J.; Bodily, D.M.; Huang, H.

    1992-05-15

    The formation and retention of methane in coalbeds was studied for ten Utah coal samples, one Colorado coal sample and eight coal samples from the Argonne Premium Coal Sample Bank.Methane gas content of the Utah and Colorado coals varied from zero to 9 cm{sup 3}/g. The Utah coals were all high volatile bituminous coals. The Colorado coal was a gassy medium volatile bituminous coal. The Argonne coals cover a range or rank from lignite to low volatile bituminous coal and were used to determine the effect of rank in laboratory studies. The methane content of six selected Utah coal seams and the Colorado coal seam was measured in situ using a special sample collection device and a bubble desorbometer. Coal samples were collected at each measurement site for laboratory analysis. The cleat and joint system was evaluated for the coal and surrounding rocks and geological conditions were noted. Permeability measurements were performed on selected samples and all samples were analyzed for proximate and ultimate analysis, petrographic analysis, {sup 13}C NMR dipolar-dephasing spectroscopy, and density analysis. The observed methane adsorption behavior was correlated with the chemical structure and physical properties of the coals.

  4. Investigation of pollutant formation of Sweet Sorghum-lignite (Orhaneli) mixtures in fluidised beds

    Energy Technology Data Exchange (ETDEWEB)

    Cubuk, M.H.; Heperkan, H.A. [Yildiz Technical University, Istanbul (Turkey)

    2004-07-01

    Most of the Turkish lignites have undesired fuel properties and they are extremely polluting. In this study, Sweet Sorghum was chosen as the energy plant. Combustion experiments of lignite and lignite-Sweet Sorghum mixtures were carried out in a fluidised bed system. The fuel-feeding ratio was set such that the thermal output of the system remained constant. Addition of Sweet Sorghum to the lignite reduces the pollutant concentration. The results were supported by experimental results.

  5. Experimental forward and reverse in situ combustion gasification of lignite with production of hydrogen-rich syngas

    Institute of Scientific and Technical Information of China (English)

    Yong Cui; Jie Liang; Zhangqing Wang; Xiaochun Zhang; Chenzi Fan; Xuan Wang

    2014-01-01

    This research focused on the feasibility of applying the forward and reverse combustion approach to the in situ gasification of lignite with the production of hydrogen-rich syngas (H2 and CO). The so-called forward combustion gasification (FCG) and reverse combustion gasification (RCG) approach in which oxygen and steam are simultaneously fed to the simulated system of underground coal gasification (UCG) was studied. A simulated system of UCG was designed and established. The underground conditions of the coal seam and strata were simulated in the system. The combustion gasification of lignite has been carried out experimentally for almost 6.5 days. The average effective content (H2 ? CO) of syngas during the FCG phase was 62.31%and the maximum content was 70.92%. For the RCG phase the corresponding figures are 61.33%and 67.91%. Thus, the feasibility of using RCG way for UCG has been demonstrated. The temperature profiles have been provided by using of 85 thermocouples during the model experiment, which portrayed the several nephograms of thermal data in the gasifier were of significance for the prospective gasification processes.

  6. Experimental Attempts to Investigate the Influence of Petrographic Properties on Drying Characteristics of Lignite in Superheated Steam Atmosphere

    Directory of Open Access Journals (Sweden)

    Anna Sciazko

    2016-05-01

    Full Text Available A superheated steam fluidized bed dryer (SSFBD in a self-heat recuperative configuration has a great potential of improving thermal efficiency of a lignite-fired power plant by recovering both of latent heat of vaporization of water kept in the fuel and part of sensible heat during the fuel processing. However, the optimal design of the dryer requires the fundamental knowledge of drying characteristics in respect to the individual properties of the utilized fuel. Experimental investigation to determine the correlation between a specific coal properties originated from geological background and its drying characteristics is thus the major concern in this paper. The investigated lignite is a representative of Turoszow deposit in Poland. Experimental attempts unveiling drying kinetics were carried out for 5 mm and 10 mm diameter spherical samples in the superheated steam atmosphere in the temperature range of 110 °C–170 °C. Simultaneous and continuous measurements of changes in weight, surface and interior temperatures and appearance on each tested sample were carried out for describing drying behavior. Analytical investigation was applied to explain the drying characteristics, which are strongly affected by the individual properties of coal and the inherent ash composition.

  7. Co-gasification of solid waste and lignite - a case study for Western Macedonia.

    Science.gov (United States)

    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

  8. The need for verification of the Polish lignite deposits owing to development and nature conservation protection on land at the surface

    Directory of Open Access Journals (Sweden)

    Naworyta Wojciech

    2016-12-01

    Full Text Available Poland is a country rich in lignite. The area where the lignite occurs occupies approx. 22% of the total surface area of the country. Geological resources of Polish lignite deposits are estimated at 23.5 billion Mg, but in the majority (69% the accuracy of their identification is poor. Nevertheless the amount of coal in Polish deposits allows - at least in theory - for mining and energy production at the current level for hundreds of years to come. It is an important raw material for the energy security of the country both currently and in the future. Because the vast majority of Polish and foreign mines use an open pit method for lignite extraction the actual amount of mineral available for the extraction depends not only on the properties of the deposit but to a large extent on the method of development of the surface land above the deposit, as well as on the sensitivity of the environment in the vicinity of any future mines. After careful analysis it can be stated that only a few of the lignite deposits may be subject to cost-effective mining operations. These deposits should be subjected to special protection as a future resource base which will ensure the energy security of the country. Some examples of domestic deposits have been presented where due to the conflict resulting from the development of the area should be deleted from the Balance Sheet of Mineral Deposits because their exploitation is irrational and uneconomic. Keeping such deposits in the Balance Sheet, and the use of large numbers in the context of their resource base leads to an unwarranted sense of wealth which consequently does not encourage the protection of these deposits which may actually be subject to rational exploitation in the near future. In summary there is a need to find a compromise in order to adequately protect all natural resources including mineral deposits.

  9. USE OF COAL DRYING TO REDUCE WATER CONSUMED IN PULVERIZED COAL POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Edward Levy

    2005-10-01

    Low rank fuels such as subbituminous coals and lignites contain significant amounts of moisture compared to higher rank coals. Typically, the moisture content of subbituminous coals ranges from 15 to 30 percent, while that for lignites is between 25 and 40 percent, where both are expressed on a wet coal basis. High fuel moisture has several adverse impacts on the operation of a pulverized coal generating unit. High fuel moisture results in fuel handling problems, and it affects heat rate, mass rate (tonnage) of emissions, and the consumption of water needed for evaporative cooling. This project deals with lignite and subbituminous coal-fired pulverized coal power plants, which are cooled by evaporative cooling towers. In particular, the project involves use of power plant waste heat to partially dry the coal before it is fed to the pulverizers. Done in a proper way, coal drying will reduce cooling tower makeup water requirements and also provide heat rate and emissions benefits. The technology addressed in this project makes use of the hot circulating cooling water leaving the condenser to heat the air used for drying the coal (Figure 1). The temperature of the circulating water leaving the condenser is usually about 49 C (120 F), and this can be used to produce an air stream at approximately 43 C (110 F). Figure 2 shows a variation of this approach, in which coal drying would be accomplished by both warm air, passing through the dryer, and a flow of hot circulating cooling water, passing through a heat exchanger located in the dryer. Higher temperature drying can be accomplished if hot flue gas from the boiler or extracted steam from the turbine cycle is used to supplement the thermal energy obtained from the circulating cooling water. Various options such as these are being examined in this investigation. This is the eleventh Quarterly Report for this project. The background and technical justification for the project are described, including potential benefits

  10. Direct comparison of XAFS spectroscopy and sequential extraction for arsenic speciation in coal

    Science.gov (United States)

    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.

  11. Alaska coal geology, resources, and coalbed methane potential

    Science.gov (United States)

    Flores, Romeo M.; Stricker, Gary D.; Kinney, Scott A.

    2004-01-01

    Estimated Alaska coal resources are largely in Cretaceous and Tertiary rocks distributed in three major provinces. Northern Alaska-Slope, Central Alaska-Nenana, and Southern Alaska-Cook Inlet. Cretaceous resources, predominantly bituminous coal and lignite, are in the Northern Alaska-Slope coal province. Most of the Tertiary resources, mainly lignite to subbituminous coal with minor amounts of bituminous and semianthracite coals, are in the other two provinces. The combined measured, indicated, inferred, and hypothetical coal resources in the three areas are estimated to be 5,526 billion short tons (5,012 billion metric tons), which constitutes about 87 percent of Alaska's coal and surpasses the total coal resources of the conterminous United States by 40 percent. Coal mining has been intermittent in the Central Alaskan-Nenana and Southern Alaska-Cook Inlet coal provinces, with only a small fraction of the identified coal resource having been produced from some dozen underground and strip mines in these two provinces. Alaskan coal resources have a lower sulfur content (averaging 0.3 percent) than most coals in the conterminous United States are within or below the minimum sulfur value mandated by the 1990 Clean Air Act amendments. The identified resources are near existing and planned infrastructure to promote development, transportation, and marketing of this low-sulfur coal. The relatively short distances to countries in the west Pacific Rim make them more exportable to these countries than to the lower 48 States of the United States. Another untapped but potential resource of large magnitude is coalbed methane, which has been estimated to total 1,000 trillion cubic feet (28 trillion cubic meters) by T.N. Smith 1995, Coalbed methane potential for Alaska and drilling results for the upper Cook Inlet Basin: Intergas, May 15 - 19, 1995, Tuscaloosa, University of Alabama, p. 1 - 21.

  12. THERMODYNAMIC ANALYSIS OF CARBON SEQUESTRATION METHODS IN LIGNITE POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Koroneos J. Christopher; Sakiltzis Christos; Rovas C. Dimitrios [Laboratory of Heat Transfer and Environmental Engineering, Department of Mechanical Engineering, Aristotle University of Thessaloniki, Thessaloniki (Greece)

    2008-09-30

    The green house effect is a very pressing issue of our times due to the big impact it will have in the future of life in our planet. The temperature increase of the earth which is the major impact of the greenhouse effect may change forever the climate and the way of life in many countries. It may lead to the reduction of agricultural production and at the end to famine, in several nations. The minimization of CO2 emissions and the introduction of new energy sources is the only solution to the catastrophe that is coming if inaction prevails. The objective of this work is to analyze the methods of the CO2 removal from the flue gases of power plants that use solid fuels. It is especially fit to the Greek conditions where the main fuel used is lignite. Three methods have been examined and compared thermodynamically. These are: (a) Removal of CO2 from the flue gas stream by absorption, (b) The combustion of lignite with pure oxygen and (c) The gasification of lignite. The lignite used in the analysis is the Greek lignite, produced at the Western Macedonia mines. The power plant, before carbon sequestration, has an efficiency of 39%, producing 330MW of electric power. After sequestration, the CO2 is compressed to pressures between 80-110 atm, before its final disposal. In the first method, the sequestration of CO2 is done utilizing a catalyst. The operation requires electricity and high thermal load which is received from low pressure steam extracted from the turbines. Additionally, electricity is required for the compression of the CO2 to 100 bars. This leads to a lower efficiency of the power plant by by 13%. In the second method, the lignite combustion is done with pure O2 produced at an air separation unit. The flue gasses are made up of CO2 and water vapor. This method requires electricity for carbon dioxide compression and the Air Separation unit, thus, the power plant efficiency is lowered by 26%. In the lignite gasification method, the products are a mixture of

  13. Coal char oxidation kinetics in air medium

    Directory of Open Access Journals (Sweden)

    Korotkikh Alexander G.

    2017-01-01

    Full Text Available Study of oxidation kinetics for three types of coal char with different carbon content in air is presented. The coal char powders of anthracite, bituminous T-grade coal and 2B-grade lignite with particle size less than 80 μm were tested. The coal char oxidation was researched by isothermal method via simultaneous TG-DSC analyzer Netzsch STA 449 Jupiter F3 in the temperature range of 1000–1200 °C. Measurements were carried out at ambient pressure. Volumetric flow rate of oxidizing medium into analyser chamber was 250 ml/min. Flow consisted of air and argon with volumetric ratio 24/1. Carbon average rate of oxidation reaction at each temperature were defined based on experimental results. Kinetic constants (the frequency factor and activation energy were defined for Arrhenius equation modified with three submodels: volumetric model, shrinking core model and random pore model. The activation energy values for anthracite are 1,6-1,7 times higher than for chars of bituminous coal and lignite.

  14. USE OF COAL DRYING TO REDUCE WATER CONSUMED IN PULVERIZED COAL POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Edward K. Levy; Nenad Sarunac; Harun Bilirgen; Hugo Caram

    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 emissions 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.

  15. Upgrading low-rank coals using the liquids from coal (LFC) process

    Energy Technology Data Exchange (ETDEWEB)

    Nickell, R.E.; Hoften, S.A. van

    1993-12-31

    Three unmistakable trends characterize national and international coal markets today that help to explain coal`s continuing and, in some cases, increasing share of the world`s energy mix: the downward trend in coal prices is primarily influenced by an excess of increasing supply relative to increasing demand. Associated with this trend are the availability of capital to expand coal supplies when prices become firm and the role of coal exports in international trade, especially for developing nations; the global trend toward reducing the transportation cost component relative to the market, preserves or enhances the producer`s profit margins in the face of lower prices. The strong influence of transportation costs is due to the geographic relationships between coal producers and coal users. The trend toward upgrading low grade coals, including subbituminous and lignite coals, that have favorable environmental characteristics, such as low sulfur, compensates in some measure for decreasing coal prices and helps to reduce transportation costs. The upgrading of low grade coal includes a variety of precombustion clean coal technologies, such as deep coal cleaning. Also included in this grouping are the coal drying and mild pyrolysis (or mild gasification) technologies that remove most of the moisture and a substantial portion of the volatile matter, including organic sulfur, while producing two or more saleable coproducts with considerable added value. SGI International`s Liquids From Coal (LFC) process falls into this category. In the following sections, the LFC process is described and the coproducts of the mild pyrolysis are characterized. Since the process can be applied widely to low rank coals all around the world, the characteristics of coproducts from three different regions around the Pacific Rim-the Powder River Basin of Wyoming, the Beluga Field in Alaska near the Cook Inlet, and the Bukit Asam region in south Sumatra, Indonesia - are compared.

  16. 26 CFR 1.631-3 - Gain or loss upon the disposal of coal or domestic iron ore with a retained economic interest.

    Science.gov (United States)

    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...

  17. Base-catalyzed depolymerization of lignin : separation of monomers

    Energy Technology Data Exchange (ETDEWEB)

    Vigneault, A. [Sherbrooke Univ., PQ (Canada). Dept. of Chemical Engineering; Johnson, D.K. [National Renewable Energy Laboratory, Golden, CO (United States); Chornet, E. [Sherbrooke Univ., PQ (Canada). Dept. of Chemical Engineering; National Renewable Energy Laboratory, Golden, CO (United States)

    2007-12-15

    Biofuels produced from residual lignocellulosic biomass range from ethanol to biodiesel. The use of lignin for the production of alternate biofuels and green chemicals has been studied with particular emphasis on the structure of lignin and its oxyaromatic nature. In an effort to fractionate lignocellulosic biomass and valorize specific constitutive fractions, the authors developed a strategy for the separation of 12 added value monomers produced during the hydrolytic base catalyzed depolymerization (BCD) of a Steam Exploded Aspen Lignin. The separation strategy was similar to vanillin purification to obtain pure monomers, but combining more steps after the lignin depolymerization such as acidification, batch liquid-liquid-extraction (LLE), followed by vacuum distillation, liquid chromatography (LC) and crystallization. The purpose was to develop basic data for an industrial size process flow diagram, and to evaluate both the monomer losses during the separation and the energy requirements. Experimentally testing of LLE, vacuum distillation and flash LC in the laboratory showed that batch vacuum distillation produced up to 4 fractions. Process simulation revealed that a series of 4 vacuum distillation columns could produce 5 distinct monomer streams, of which 3 require further chromatography and crystallization operations for purification. 22 refs., 4 tabs., 8 figs.

  18. Influence of oxidation in aqueous medium on the structure and properties of lignites

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Kucukbayrak, S. [Istanbul Technical University, Istanbul (Turkey). Chemical and Metallurgical Engineering Faculty

    2000-05-01

    In this paper, the effect of oxygen uptake on the structure and properties of lignites was investigated using five different Turkish lignites. Lignite samples were oxidised in aqueous medium at 423 K under 1.5 MPa partial pressure of oxygen for 60 min. Relations between the oxygen uptake and the elemental compositions of the lignite samples were investigated. FT-i.r. technique was applied to the original and oxidised lignite samples to investigate functional group analyses. Mercury porosimetry analyses of the samples were carried out up to about 220 MPa. Effect of oxygen uptake on the bulk density, apparent density, porosity, and pore radius of the lignite samples were compared. Differential Thermogravimetry (DTG) technique was performed to compare the thermal reactivity of the original and oxidised lignite samples. 20 refs., 8 figs., 7 tabs.

  19. Regional Studies Program. Extraction of North Dakota lignite: environmental and reclamation issues

    Energy Technology Data Exchange (ETDEWEB)

    LaFevers, J.R.; Johnson, D.O.; Dvorak, A.J.

    1976-12-01

    This study, sponsored by the U.S. Energy Research and Development Administration, addresses the environmental implications of extraction of coal in North Dakota. These implications are supported by details of the geologic and historical background of the area of focus, the lignite resources in the Fort Union coalfield portion. The particular concentration is on the four-county area of Mercer, Dunn, McLean, and Oliver where substantial coal reserves exist and a potential gasification plant site has been identified. The purposes of this extensive study are to identify the land use and environmental problems and issues associated with extraction; to provide a base of information for assessing the impacts of various levels of extraction; to examine the economics and feasibility of reclamation; and to identify research that needs to be undertaken to evaluate and to improve reclamation practices. The study also includes a description of the physical and chemical soil characteristics and hydrological and climatic factors entailed in extraction, revegetation, and reclamation procedures.

  20. Geochemical investigation of the potential for mobilizing non-methane hydrocarbons during carbon dioxide storage in deep coal beds

    Science.gov (United States)

    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.

  1. Geology and coal potential of Somaliland

    Energy Technology Data Exchange (ETDEWEB)

    M.Y. Ali [Petroleum Institute, Abu Dhabi (United Arab Emirates)

    2009-07-01

    Geological field mapping along with available geological and drilling data suggest that Somaliland (Northwestern Somalia) has favourable stratigraphy and structure for coal deposits. Lignitic to sub-bituminous coal deposits with ages from Jurassic to Oligocene-Miocene occur in various locations across the country including Hed-Hed valley south of Onkhor, Guveneh hills north of Las Dureh and Daban Basin southeast of Berbera. However, the coal occurrence at Hed-Hed has both the greatest thickness and highest quality. These deposits have the potential to provide an important alternative fuel resource which could alleviate the growing shortage of traditional fuels and assist in reducing the country's dependence on imported energy. However, further investigation, including drilling and laboratory analyses, still needs to be carried out, particularly on the Upper Cretaceous coal seams to evaluate the quality and resource potential of the deposits.

  2. Thermal properties of different rank coals

    Energy Technology Data Exchange (ETDEWEB)

    Serdar Yaman; Hanzade Haykiri-Acma [Istanbul Technical University, Istanbul (Turkey). Dept. of Chemical Engineering

    2007-07-01

    Thermal properties of various coal samples which have different rank and petrography were investigated under both inert and oxidizing conditions up to 900{sup o}C in a thermal analysis system. Peat, anthracite, and bituminous coal samples from different countries and various lignites from Turkey such as Askale, Soma, and Elbistan were used. DTA (Differential Thermal Analysis) and TGA (Thermogravimetric Analysis) techniques were applied. DTG (Derivative Thermogravimetric) curves were derived and interpreted considering the physical and chemical properties, and the rank of coals. Pyrolytic chars obtained from the inert atmosphere experiments were examined applying SEM (Scanning Electron Microscopy) and XRD (X-ray Diffractometry) techniques. It was found that the thermal reactivity and the apparent thermal properties of different rank coals differ considerably under both conditions. 6 refs., 4 figs., 3 tabs.

  3. More efficient cleaning concepts for stepping up availability of lignite-fired power plants (Ligpower)

    Energy Technology Data Exchange (ETDEWEB)

    G. Wiechers; B. Wessel; S. Goudanis; F. Kluger; G. Riley [RWE Power AG, Koeln (Germany)

    2009-07-01

    The quality of lignite extracted in various deposits differs considerably in part. The impact of changed major coal quality parameters on steam generator operation became evident in the form of increased deposit formation on the boiler's heating surfaces. Successful countermeasures were launched, but the bottleneck of the problem continues to be the cleaning of the first convection heating surfaces downstream of the furnace. As the cleaning facilities available so far (soot blowers) have not proved sufficient for these areas of application despite all optimisation efforts made, new processes have to be developed. In contrast to the methods applied so far, these processes do not use the common cleaning medium steam but work on the basis of alternative cleaning media. Within the scope of the Ligpower project, such alternative cleaning methods were selected and subjected to extensive testing on commercial utility boilers. Since a more intensive cleaning of superheater tubes involves increased stress of the tube material, we developed new, more resistant, superheater designs and installed these in a 600 MW unit. The transferability of the findings made was ensured by a comparison of the lignites used. To permit the cleaning device to be controlled as needed, we developed a programme that analyses the degree of fouling of the boiler and generates suggestions for its cleaning. In addition, a tube-fin superheater design was calculated and optimised in terms of fluid dynamics. The extensive tests showed which cleaning methods have suitable approaches to cleaning. By testing them over several years, we gained important information about equipment design. The superheater design could be tested only to a limited degree. Thus, we obtained additional findings in tests using a test heating surface that was mounted on a 300 MW boiler. 77 figs., 5 tabs., 3 apps.

  4. Advanced power assessment for Czech lignite task 3.6. Topical report

    Energy Technology Data Exchange (ETDEWEB)

    Sondreal, E.A.; Mann, M.D.; Weber, G.W.; Young, B.C.

    1995-12-01

    Major reforms in the Czech energy sector have been initiated to reverse 40 years of central planning, subsidized energy pricing, unchecked pollution from coal-fired plants, concerns over nuclear safety and fuel cycle management, and dependence on the former U.S.S.R. for oil, gas, and nuclear fuel processing. Prices for electricity, heat, and natural gas paid by industry are close to western levels, but subsidized prices for households are as much as 40% lower and below economic cost. State control of major energy enterprises is being reduced by moving toward government-regulated, investor-owned companies to raise needed capital, but with a strategic stake retained by the state. Foreign firms will participate in privatization, but they are not expected to acquire a controlling interest in Czech energy companies. Economic conditions in the Czech Republic are now improving after the disruptions caused by restructuring since 1989 and separation of the former Czech and Slovak Federal Republics in January 1993. The downturn in the economy after 1989 was concentrated in energy-intensive heavy industry, and recovery is paced by consumer trade, services, light industry and construction. Energy use in relation to gross domestic product (GDP) has declined, but it is still significantly higher than in OECD (Organization for Economic Cooperation and Development) countries. The GDP increased by 2% in 1994 after dropping 22% between 1989 and 1993. A positive balance of payments has been achieved, with foreign investment offsetting a small trade deficit. The government`s external debt is only 4% of GDP. This report studies the application of lignite resources within the newly formulated energy policies of the republic, in light of a move toward privatization and stronger air pollution regulations. Lignite has represented the major energy source for the country.

  5. Impact of 80% F-76/20% Hydrotreated Depolymerized Cellulosic Diesel (HDCD-76) on Coalescence

    Science.gov (United States)

    2014-02-25

    Impact of 80% F-76/20% Hydrotreated Depolymerized Cellulosic Diesel (HDCD-76) on Coalescence NF&LCFT REPORT 441/14-008 25 February 2014... Hydrotreated Depolymerized Cellulosic Diesel IAW...than existing petroleum sourced fuels. One such fuel that is undergoing qualification testing is an 80% petroleum F-76 and 20% Hydrotreated

  6. The Depolymerization of Poly(Ethylene Terephthalate) (PET) Using N-Heterocyclic Carbenes from Ionic Liquids

    Science.gov (United States)

    Kamber, Nahrain E.; Tsujii, Yasuhito; Keets, Kate; Waymouth, Robert M.; Pratt, Russell C.; Nyce, Gregory W.; Hedrick, James L.

    2010-01-01

    The depolymerization of the plastic polyethylene terephthalate (PET or PETE) is described in this laboratory procedure. The transesterification reaction used to depolymerize PET employs a highly efficient N-heterocyclic carbene catalyst derived from a commercially available imidazolium ionic liquid. N-heterocyclic carbenes are potent nucleophilic…

  7. Mineralogy and geochemistry of density-separated Greek lignite fractions

    NARCIS (Netherlands)

    Iordanidis, A.; Doesburg, van J.D.J.

    2006-01-01

    In this study, lignite samples were collected from the Ptolemais region, northern Greece, homogenized, crushed to less than I nun, and separated in three density fractions using heavy media. The mineralogical investigation of the density fractions showed a predominance of pyrite in the light fractio

  8. Influences of different substrates on simulated lignite biogas production

    Institute of Scientific and Technical Information of China (English)

    Wang Aikuan; Qin Yong; Shao Pei

    2015-01-01

    Using lignite samples, selected from Zhaotong basin, Yunnan province, China, as the parent source, sim-ulating experiments of lignite biogas were conducted with 0.1% methanol, 5 mg/L yeast extract and 0.2 mol/L sodium acetate solutions as the exogenous substance respectively. Variation characteristics of gas production, gas composition, VFA content and activity of coenzyme F420 in the simulated process were analyzed to discuss the influence of different substrates on lignite biogas generation. The results show that 0.1%methanol and 5 mg/L yeast extract solutions increase VFA contents in the biogas gener-ation system (p <0.05) and inhibit coenzyme F420 and methanogen activities significantly, so they decrease both gas amounts (p<0.05) and CH4 contents (p<0.05). 0.2 mol/L sodium acetate solution acti-vates coenzyme F420 and methanogen activities and improves the efficiency of enzymatic reaction, so the gas quantity (p<0.05) and the CH4 content (p<0.01) increase significantly. Therefore, sodium acetate can be one kind of good exogenous substance for the generation of lignite biogenic gas.

  9. Kinetic features of pyrolysis of asphaltenes from lignite semicoking tar

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Ryl' tsova, S.V.; Rozental, D.A.; Proskuryakov, V.A.; Polovetskaya, O.S.

    2000-07-01

    The kinetic features of accumulation of the main gaseous and some liquid products in pyrolysis of asphaltenes from lignite semicoking tar at 750-900{degree}C (contact time 0.5-6.0 s) were studied. The overall reaction order of accumulation of certain compounds was determined, and possible pathways for their formation were suggested.

  10. Sulfate Reduction at a Lignite Seam: Microbial Abundance and Activity.

    Science.gov (United States)

    Detmers, J.; Schulte, U.; Strauss, H.; Kuever, J.

    2001-10-01

    In a combined isotope geochemical and microbiological investigation, a setting of multiple aquifers was characterized. Biologically mediated redox processes were observed in the aquifers situated in marine sands of Tertiary age and overlying Quaternary gravel deposits. Intercalated lignite seams define the aquitards, which separate the aquifers. Bacterial oxidation of organic matter is evident from dissolved inorganic carbon characterized by average carbon isotope values between ?18.4 per thousand and ?15.7 per thousand (PDB). Strongly positive sulfur isotope values of up to +50 per thousand (CTD) for residual sulfate indicate sulfate reduction under closed system conditions with respect to sulfate availability. Both, hydrochemical and isotope data are thus consistent with the recent activity of sulfate-reducing bacteria (SRB). Microbiological investigations revealed the presence of an anaerobic food chain in the aquifers. Most-probable-number (MPN) determinations for SRB and fermenting microorganisms reached highest values at the interface between aquifer and lignite seam (1.5 x 103 cells/g sediment dry mass). Five strains of SRB were isolated from highest MPN dilutions. Spore-forming bacteria appeared to dominate the SRB population. Sulfate reduction rates were determined by the 35S-radiotracer method. A detailed assessment indicates an increase in the reduction rate in proximity to the lignite seam, with a maximum turnover of 8.4 mM sulfate/a, suggesting that lignite-drived compounds represent the substrate for sulfate reduction.

  11. Mineralogy and geochemistry of density-separated Greek lignite fractions

    NARCIS (Netherlands)

    Iordanidis, A.; Doesburg, van J.D.J.

    2006-01-01

    In this study, lignite samples were collected from the Ptolemais region, northern Greece, homogenized, crushed to less than I nun, and separated in three density fractions using heavy media. The mineralogical investigation of the density fractions showed a predominance of pyrite in the light fractio

  12. Pyrolysis kinetics of phenols from lignite semicoking tar

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Polovetskaya, O.S.; Proskuryakov, V.A.; Shavyrina, O.A. [Leo Tolstoy Tula State Pedag University, Tula (Russian Federation)

    2002-11-01

    The features of pyrolysis of phenols from lignite semicoking tar were studied. The activation energy and order of the reactions of accumulation of methane, hydrogen, carbon monoxide and dioxide, naphthalene and its methyl homologs, phenols, and isomeric cresols and dimethylphenols were determined.

  13. Petrographic compositions of Paleozoic coals of Mongolia

    Science.gov (United States)

    Jargal, Luvsanchultem; Erdenetsogt, Bat-Orshikh

    2016-04-01

    In Mongolia, the deposition of coal bearing strata commenced in Pennsylvanian, and continued in Upper Permian, in Lower-Middle Jurassic and finally in Lower Cretaceous time. Pennsylvanian coal seams were deposited in Western Mongolia, where peat formation was initially developed in the southernmost part and later gradually shifted to northward. By the Late Permian, the locus of coal formation had changed and main peat accumulation took place in southern Mongolia. Lower-Middle Jurassic coal was accumulated in western, northern and eastern Mongolia. During this time, peat forming condition was comparatively stable in entire Mongolia. In the Early Cretaceous, thick and extensive coal was formed in the Eastern Mongolia. Due to this general trend of peat accumulation, coal rank decreases from west (bituminous) to east (lignite). The significant portion of Pennsylvanian and Upper Permian coal reserves, existed in western and southern Mongolia, are coking coal. Thus, petrographical studies of the coals are notably important. However, previous studies of Paleozoic coals have been sparse, and only few deposits have been conducted. The maceral compositions of Western Mongolian Pennsylvanian coals such as Khushuut, Maanit, Khurengol, Zeegt, Tsagaangol, Nuurstkhotgor, Khartarvagatai and Olonbulag were studied. The results show that the coals are dominated by vitrinite (45 vol.% to 71 vol.%) and inertinite (28 vol.% to 53vol.%) macerals. Liptinite contents are low, less than 4 vol.%. In addition, vitrinite reflectance values (Rmax in oil) of Khushuut (1.85%), Maanit (0.92%), Khurengol (1.4%), Zeegt (0.86%), Tsagaangol (3.6%), Nuurstkhotgor (0.9%), Khartarvagatai (1.1%) and Olonbulag (1.7%) were determined. Upper Permian coals in southern Mongolia (Tavantolgoi, Nariinsukhait, Jargalant, Tsagaantolgoi, Buduuniikhyar) are dominated by vitrinite (55 vol.% to 78 vol.%) and inertinite macerals (19 vol.% to 44 vol.%). Liptinite contents range from 1 vol.% to 7 vol.%. The vitrinite

  14. Irradiation depolymerized guar gum as partial replacement of gum Arabic for microencapsulation of mint oil.

    Science.gov (United States)

    Sarkar, Shatabhisa; Gupta, Sumit; Variyar, Prasad S; Sharma, Arun; Singhal, Rekha S

    2012-11-06

    Spray dried microcapsules of mint oil were prepared using gum Arabic alone and its blends with radiation or enzymatically depolymerized guar gum as wall materials. Microcapsules were evaluated for retention of mint oil during 8-week storage during which qualitative changes in encapsulated mint oil was monitored using principal component analysis. The microcapsules with radiation depolymerized guar gum as wall material component could better retain major mint oil compounds such as menthol and isomenthol. The t(1/2) calculated for mint oil in microcapsules of gum Arabic, gum Arabic:radiation depolymerized guar gum (90:10), gum Arabic:enzyme depolymerized guar gum (90:10) was 25.66, 38.50, and 17.11 weeks, respectively. The results suggested a combination of radiation depolymerized guar gum and gum Arabic to show better retention of encapsulated flavour than gum Arabic alone as wall material.

  15. Interaction between biomass and different rank coals during co-pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Haykiri-Acma, H.; Yaman, S. [Istanbul Technical University, Chemical and Metallurgical Engineering Faculty, Chemical Engineering Department, 34469 Maslak, Istanbul (Turkey)

    2010-01-15

    Effects of biomass on the pyrolytic decomposition of different rank coals were investigated by non-isothermal Thermogravimetric Analysis (TGA) method from ambient to 900 C with a heating rate of 40 C/min under nitrogen. Hazelnut shell (HS) which is a woody biomass species was added as much as 10 wt% to coals such as peat, lignite, bituminous coal, and anthracite to obtain coal/biomass blends for co-pyrolysis runs. Effects of HS present in the blends were evaluated regarding the apparent decomposition rates and the char yields. It was found that the addition of thermally reactive HS led to some increases in the volatilization rates of coals especially at temperatures below 500 C. Besides, the char yields revealed unexpected variations in case of low rank coals. Although, HS addition did not play significant role on the char yields of bituminous coal and anthracite, considerable deviations from the theoretical char yields were detected in the case of peat and lignites. The presence of HS led to increasing char weight for peat, while the char weights for lignites decreased seriously. These variations were interpreted, and it can be concluded that these variations cannot be explained by simple additive behavior, and the existence of synergistic interactions should be taken into account. (author)

  16. CO2 Emission Factors for Coals

    Directory of Open Access Journals (Sweden)

    P. Orlović-Leko

    2015-03-01

    Full Text Available Emission factors are used in greenhouse gas inventories to estimate emissions from coal combustion. In the absence of direct measures, emissions factors are frequently used as a quick, low cost way to estimate emissions values. Coal combustion has been a major contributor to the CO2 flux into the atmosphere. Nearly all of the fuel carbon (99 % in coal is converted to CO2 during the combustion process. The carbon content is the most important coal parameter which is the measure of the degree of coalification (coal rank. Coalification is the alteration of vegetation to form peat, succeeded by the transformation of peat through lignite, sub-bituminous, bituminous to anthracite coal. During the geochemical or metamorphic stage, the progressive changes that occur within the coal are an increase in the carbon content and a decrease in the hydrogen and oxygen content resulting in a loss of volatiles. Heterogeneous composition of coal causes variation in CO2 emission from different coals. The IPCC (Intergovernmental Panel on Climate Change has produced guidelines on how to produce emission inventories which includes emission factors. Although 2006 IPCC Guidelines provided the default values specified according to the rank of the coal, the application of country-specific emission factors was recommended when estimating the national greenhouse gas emissions. This paper discusses the differences between country-specific emission factors and default IPCC CO2 emission factors, EF(CO2, for coals. Also, this study estimated EF(CO2 for two different types of coals and peat from B&H, on the basis fuel analyses. Carbon emission factors for coal mainly depend on the carbon content of the fuel and vary with both rank and geographic origin, which supports the idea of provincial variation of carbon emission factors. Also, various other factors, such as content of sulphur, minerals and macerals play an important role and influence EF(CO2 from coal. Carbonate minerals

  17. Inorganic geochemical characterisation of the Velenje lignite in the representative P-9k/92 borehole profile (Slovenia

    Directory of Open Access Journals (Sweden)

    Miloš Markič

    2006-12-01

    Full Text Available The study is based on 30 lignite, 6 footwall and 3 hanging-wall interval samples. Lignite seam of the Pliocene age is 101 m thick in the treated profile.Minorelementgeochemistryis evaluated by the contents of 11 standard oxides, among which SiO2, Al2O3, Fe2O3 and CaO form the bulk composition. Trace-element characterization is based on contents of 46 elements. Stot., Ctot., Corg. and loss on ignition (LOI at 1000 ˚C were analysed in addition. All analyses (by ICP-AES, ICP-MS, Leco were carried out on the “whole lignite”/“whole rock” samples in the Acme Analytical Laboratories (Canada. Recalculation to the “pure inorganic matter” basis was carried out in order to obtain realistic relations between contentsof minor element oxides. Contents of the minor element oxides in the inorganic matter are dependant on the ash content, and, an ash content of 20-25 % was found out as an important “geochemical threshold”. SiO2 + Al2O3, together with positively corelated K2O and TiO2, increase with increasing ash content. On the contrary, CaO, MgO and Fe2O3, they increase with decreasing ash content. Affinity of organic binding of Ca,Mg,and(probablyof Fe is ascertained by negligible contents of Cinorg. Abundances of the great majority of trace elements are mostly lower and/or normal in comparison to the world coals. However, As, U, and Mo are typomorphic for the treated lignite. In spite of that, they are not critical. Widespread areas of different lithologies with higher contents of these elements are known throughout the world as well as in Slovenia.

  18. Coal in Asia-Pacific. Vo1 7, No. 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    In China, there are bottle-necks of the coal transportation capacity in the major inter-regional routes. The Chinese Government`s eighth and ninth five-year plans intend to increase the capacity. In the 9% growth case, the planned railway transport capacity will be critical. Measures are considered, as to promotion of coal dressing, transport as electric power, construction of nuclear power plants and hydraulic power plants, and construction of coal water slurry pipe lines. Japan`s coal policy includes the structural adjustment of coal mining industry, and a new policy for coal in the total energy policy. To secure the stable overseas coal supply, NEDO has a leading part in overseas coal resources development. Coal demand and supply, mining technology, mine safety, coal preparation and processing technology, and comprehensive coal utilization technology including clean coal technology in Japan are described. At present, Thailand is progressing with the seventh plan, and the development of domestic energy emphasize lignite, natural gas, and oil. Thai import demand for high-quality coal is to be increasing. Japan`s cooperation is considered to be effective for the environmental problems. 12 figs., 40 tabs.

  19. Structural Snapshots of Heparin Depolymerization by Heparin Lyase I

    Energy Technology Data Exchange (ETDEWEB)

    Han, Young-Hyun; Garron, Marie-Line; Kim, Hye-Yeon; Kim, Wan-Seok; Zhang, Zhenqing; Ryu, Kyeong-Seok; Shaya, David; Xiao, Zhongping; Cheong, Chaejoon; Kim, Yeong Shik; Linhardt, Robert J.; Jeon, Young Ho; Cygler, Miroslaw; (SNU); (Korea BSI); (McGill); (UST-Korea); (Rensselaer)

    2010-01-12

    Heparin lyase I (heparinase I) specifically depolymerizes heparin, cleaving the glycosidic linkage next to iduronic acid. Here, we show the crystal structures of heparinase I from Bacteroides thetaiotaomicron at various stages of the reaction with heparin oligosaccharides before and just after cleavage and product disaccharide. The heparinase I structure is comprised of a {beta}-jellyroll domain harboring a long and deep substrate binding groove and an unusual thumb-resembling extension. This thumb, decorated with many basic residues, is of particular importance in activity especially on short heparin oligosaccharides. Unexpected structural similarity of the active site to that of heparinase II with an ({alpha}/{alpha}){sub 6} fold is observed. Mutational studies and kinetic analysis of this enzyme provide insights into the catalytic mechanism, the substrate recognition, and processivity.

  20. Oxy-fuel combustion of millimeter-sized coal char: Particle temperatures and NO formation

    DEFF Research Database (Denmark)

    Brix, Jacob; Navascués, Leyre Gómez; Nielsen, Joachim Bachmann;

    2013-01-01

    In this work, differences in particle temperature and NO yield during char oxidation in O2/N2 and O2/CO2 atmospheres, respectively, have been examined. A laboratory scale fixed bed reactor, operated isothermally at 1073 K, was used for combustion of millimeter-sized lignite and bituminous coal ch...

  1. Filament depolymerization can explain chromosome pulling during bacterial mitosis.

    Science.gov (United States)

    Banigan, Edward J; Gelbart, Michael A; Gitai, Zemer; Wingreen, Ned S; Liu, Andrea J

    2011-09-01

    Chromosome segregation is fundamental to all cells, but the force-generating mechanisms underlying chromosome translocation in bacteria remain mysterious. Caulobacter crescentus utilizes a depolymerization-driven process in which a ParA protein structure elongates from the new cell pole, binds to a ParB-decorated chromosome, and then retracts via disassembly, pulling the chromosome across the cell. This poses the question of how a depolymerizing structure can robustly pull the chromosome that disassembles it. We perform Brownian dynamics simulations with a simple, physically consistent model of the ParABS system. The simulations suggest that the mechanism of translocation is "self-diffusiophoretic": by disassembling ParA, ParB generates a ParA concentration gradient so that the ParA concentration is higher in front of the chromosome than behind it. Since the chromosome is attracted to ParA via ParB, it moves up the ParA gradient and across the cell. We find that translocation is most robust when ParB binds side-on to ParA filaments. In this case, robust translocation occurs over a wide parameter range and is controlled by a single dimensionless quantity: the product of the rate of ParA disassembly and a characteristic relaxation time of the chromosome. This time scale measures the time it takes for the chromosome to recover its average shape after it is has been pulled. Our results suggest explanations for observed phenomena such as segregation failure, filament-length-dependent translocation velocity, and chromosomal compaction.

  2. Filament depolymerization can explain chromosome pulling during bacterial mitosis.

    Directory of Open Access Journals (Sweden)

    Edward J Banigan

    2011-09-01

    Full Text Available Chromosome segregation is fundamental to all cells, but the force-generating mechanisms underlying chromosome translocation in bacteria remain mysterious. Caulobacter crescentus utilizes a depolymerization-driven process in which a ParA protein structure elongates from the new cell pole, binds to a ParB-decorated chromosome, and then retracts via disassembly, pulling the chromosome across the cell. This poses the question of how a depolymerizing structure can robustly pull the chromosome that disassembles it. We perform Brownian dynamics simulations with a simple, physically consistent model of the ParABS system. The simulations suggest that the mechanism of translocation is "self-diffusiophoretic": by disassembling ParA, ParB generates a ParA concentration gradient so that the ParA concentration is higher in front of the chromosome than behind it. Since the chromosome is attracted to ParA via ParB, it moves up the ParA gradient and across the cell. We find that translocation is most robust when ParB binds side-on to ParA filaments. In this case, robust translocation occurs over a wide parameter range and is controlled by a single dimensionless quantity: the product of the rate of ParA disassembly and a characteristic relaxation time of the chromosome. This time scale measures the time it takes for the chromosome to recover its average shape after it is has been pulled. Our results suggest explanations for observed phenomena such as segregation failure, filament-length-dependent translocation velocity, and chromosomal compaction.

  3. The second International Energy Agency coal conference (Hong Kong)

    Energy Technology Data Exchange (ETDEWEB)

    1994-05-01

    The official name of the meeting was the IEA Second International Conference On the Clean and Efficient Use of Coal and Lignite. Co-sponsored by the International Energy Agency (IEA), Australia, Japan, the United States and the United Nations, it was held on Dec. 1-3, 1993 at the JW Marriot Hotel in Hong Kong. As summarized in the subtitle of the conference, 'Its role in energy, environmental and life' the reports and debate ranged beyond the technical, to social ramifications of coal and lignite use. The participants in the conference numbered 176, from 26 countries in Asia, Oceania, North America, Europe and Africa. Topics included: a report on the recent WE Commission findings on coal until 2020; the Chinese coal industry; the economics of coal technology; SO[sub 2] emissions and abatement; Asia Pacific coal use strategies, needs, plans and opportunities; the role of the World Bank; Indonesia's power situation; the situation in Asian states; new technologies; South Korea and coal and the environment. 2 figs., 1 tab., 1 plate.

  4. Relations of petrographical and geochemical parameters in the middle Miocene Lavanttal lignite (Austria)

    Energy Technology Data Exchange (ETDEWEB)

    Bechtel, A. [Department Angewandte Geowissenschaften und Geophysik, Montanuniversitaet Leoben, Peter-Tunner-Str. 5, A-8700 Leoben (Austria); Mineralogisch-Petrologisches Institut, Universitaet Bonn, Poppelsdorfer Schloss, D-53115 Bonn (Germany); Reischenbacher, D.; Sachsenhofer, R.F.; Gratzer, R. [Department Angewandte Geowissenschaften und Geophysik, Montanuniversitaet Leoben, Peter-Tunner-Str. 5, A-8700 Leoben (Austria); Luecke, A. [Institut fuer Chemie und Dynamik der Geosphaere V: Sedimentaere Systeme (ICG V), Forschungszentrum Juelich, D-52425 Juelich (Germany); Puettmann, W. [Institute of Atmospheric and Environmental Sciences, Department of Environmental Chemistry, J. W. Goethe-Universitaet, Georg-Voigt-Str. 14, D-60054 Frankfurt a.M. (Germany)

    2007-05-01

    Samples from two lignite seams (Lower Seam, Upper Seam) of the Lavanttal basin (Austria) and additional xylite were investigated for variations in maceral composition, petrography-based facies indicators, bulk geochemical parameters, and molecular composition of hydrocarbons. Both seams originated in a topogenous mire and evolved within a transgressive setting. The final drowning of the mire is indicated by sapropelic shales. Whereas the sapropelic shale overlying the Lower Seam was deposited in a freshwater lake, the sapropelic shale above the Upper Seam represents a brackish lake. Numerous relationships are found between petrography-based facies indicators and the geochemical composition of organic matter. The contents of macerals of the liptinite group are positively correlated with soluble organic matter (SOM) yields and hydrogen index (HI). Consistent with maceral composition and high HI values, enhanced proportions of short-chain n-alkanes, which are predominantly found in algae and microorganisms, are obtained from samples of the sapropelic shales. The final drowning of the mire is reflected by decreasing pristane/phytane ratios, due to the rise in (ground)water table and the establishment of anaerobic conditions, as well as by decreasing ratios of diasterenes/sterenes, indicating increasing pH values in the mire. The degree of gelification of plant tissue (gelification index) is governed by the microbial activity in the mire, as indicated by the hopanes concentration. The differences in floral assemblage during the formation of the Lavanttal lignite seams are reflected by major differences in tissue preservation. Preservation of plant tissue (TPI) in the Lavanttal lignite is obviously controlled by the presence/absence of decay-resistant gymnosperms in the peat-forming vegetation, and additionally influenced by the relative contribution of wood to coal formation. The results provide evidence that valuable information for coal facies characterization could

  5. Low-rank coal study : national needs for resource development. Volume 2. Resource characterization

    Energy Technology Data Exchange (ETDEWEB)

    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 by 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.

  6. Baseline risk assessment of ground water contamination at the inactive uraniferous lignite ashing site near Bowman, North Dakota

    Energy Technology Data Exchange (ETDEWEB)

    1994-11-01

    This baseline risk assessment of ground water contamination at the inactive uraniferous lignite ashing site near Bowman, North Dakota, evaluates the potential impacts to public health or the environment from contaminated ground water at this site. This contamination is a result of the uraniferous lignite ashing process, when coal containing uranium was burned to produce uranium. Potential risk is quantified only for constituents introduced by the processing activities and not for the constituents naturally occurring in background ground water in the site vicinity. Background ground water, separate from any site-related contamination, imposes a percentage of the overall risk from ground water ingestion in the Bowman site vicinity. The US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project is developing plans to address soil and ground water contamination at the site. The UMTRA Surface Project involves the determination of the extent of soil contamination and design of an engineered disposal cell for long-term storage of contaminated materials. The UMTRA Ground Water Project evaluates ground water contamination. Based on results from future site monitoring activities as defined in the site observational work plan and results from this risk assessment, the DOE will propose an approach for managing contaminated ground water at the Bowman site.

  7. Thermogravimetric analysis and pyrolytic kinetic study on coal/biomass blends

    Energy Technology Data Exchange (ETDEWEB)

    Wu Hong-xiang; Li Hai-bin; Zhao Zeng-li [Chinese Academy of Sciences, Guangzhou (China). Guangzhou Institute of Energy Conversion

    2009-07-01

    Three biomass and one lignite were co-pyrolyzed in a thermo gravimetric analyzer to investigate the pyrolysis performance of each material, as well as their mixtures. The lignite was blended with biomass at the percentage of 10%, 20%, 35% and 50% respectively. The results show that the initial volatile releasing temperature and the first maximum peak temperature of co-pyrolysis increase with increasing amount of lignite in blends. The position of the second maximum peak is shifted to lower temperature as the percentage of biomass is raised. Co-pyrolysis of coal/biomass blends produces more char than the summation of individual lignite and biomass pyrolysis. The pyrolysis of demineralization and devolatilization rice straw show that the alkali and alkaline earth metals promote pyrolysis of the blends at lower temperature, while Si inhibits the pyrolysis rate. Both volatile and mineral matter in biomass interact with lignite in co-pyrolysis. The synergistic effects in the co-pyrolysis of biomass and coal are suggested. 22 refs., 6 figs., 6 tabs.

  8. Coordination of the works of overburden removal and coal production at Thorez mine

    Energy Technology Data Exchange (ETDEWEB)

    Szabo, I.

    1987-01-01

    The last 10 years are examined from the point of view of the evaluation of the relationships among lignite production, overburden removal, exposed coal reserves and coal quality, as a function of production costs. The most economic solution would be not to use external capacities and to operate own high-duty machineries in an optimal manner. External capacities should be applied only when the overburden removal cannot be solved by large-machine technology.

  9. Biochemically enhanced methane production from coal

    Science.gov (United States)

    Opara, Aleksandra

    For many years, biogas was connected mostly with the organic matter decomposition in shallow sediments (e.g., wetlands, landfill gas, etc.). Recently, it has been realized that biogenic methane production is ongoing in many hydrocarbon reservoirs. This research examined microbial methane and carbon dioxide generation from coal. As original contributions methane production from various coal materials was examined in classical and electro-biochemical bench-scale reactors using unique, developed facultative microbial consortia that generate methane under anaerobic conditions. Facultative methanogenic populations are important as all known methanogens are strict anaerobes and their application outside laboratory would be problematic. Additional testing examined the influence of environmental conditions, such as pH, salinity, and nutrient amendments on methane and carbon dioxide generation. In 44-day ex-situ bench-scale batch bioreactor tests, up to 300,000 and 250,000 ppm methane was generated from bituminous coal and bituminous coal waste respectively, a significant improvement over 20-40 ppm methane generated from control samples. Chemical degradation of complex hydrocarbons using environmentally benign reagents, prior to microbial biodegradation and methanogenesis, resulted in dissolution of up to 5% bituminous coal and bituminous coal waste and up to 25% lignite in samples tested. Research results confirm that coal waste may be a significant underutilized resource that could be converted to useful fuel. Rapid acidification of lignite samples resulted in low pH (below 4.0), regardless of chemical pretreatment applied, and did not generate significant methane amounts. These results confirmed the importance of monitoring and adjusting in situ and ex situ environmental conditions during methane production. A patented Electro-Biochemical Reactor technology was used to supply electrons and electron acceptor environments, but appeared to influence methane generation in a

  10. Perspectives of the German lignite industry in 2008; Perspektiven der deutschen Braunkohlenindustrie 2008

    Energy Technology Data Exchange (ETDEWEB)

    Hartung, M. [RWE Power AG, Koeln (Germany). Ressort Braunkohlengewinnung, -stromerzeugung und -veredlung; Milojcic, G. [Bundesverband Braunkohle (DEBRIV), Koeln (Germany)

    2008-05-15

    Lignite companies, specifically Vattenfall and RWE, have been setting out on this route, but there is still a long way to go. We intend to make the necessary efforts, and the lignite companies have a special motivation. Lignite is an increasingly valuable resource. This is shown by developments on raw-material markets. Our task is to further develop power plant engineering in order to help ensure that this remains the case tomorrow as well. So, the lignite industry's avowal of CCS is underpinned by a very tangible interest. The value of domestic lignite should be retained for the longer term. Happily, lignite extraction in all mining areas enjoys the wide acceptance of the population and regional politicians. (orig.)

  11. Study of the mechanisms by which microorganisms solubilize and/or liquefy Spanish coals

    Energy Technology Data Exchange (ETDEWEB)

    Laborda, F.; Fernandez, M.; Luna, N.; Monistrol, I.F. [Campus Universitario Alcala de Henares (Spain). Dept. de Microbiologia y Parasitologia

    1997-11-01

    Cell-free culture filtrates of fungi were tested on their capacity to solubilize different Spanish coals. Two kinds of cell-free culture filtrates were used: a non-coal induced cell-free culture filtrate (NCI) and a coal induced cell-free culture filtrate (CI). Either of them was able to solubilize hard coal, subbituminous coal and most efficiently lignite. In most of the culture filtrates the measured pH values were approximately neutral, even acidic in some cases. The agent(s) for coal solubilization that was present in NCI was heat stable (100{degree}C) but the active substance(s) in CI was thermosensitive. Microorganisms were observed by electron microscopy to grow on the coal surface and cover it. A fibrilar extracelluar polymer which could facilitate not only the adhesion to the coal particle but microbial attack too, was produced by the microorganisms. 11 refs., 8 figs., 3 tabs.

  12. Diterpanes, triterpanes, steranes, and aromatic hydrocarbons in natural bitumens and pyrolysates from different humic coals

    Science.gov (United States)

    Lu, Shan-Tan; Kaplan, Isaac R.

    1992-01-01

    Data are presented on the distribution of diterpanes, triterpanes, steranes, and aromatic hydrocarbons in the natural bitumens extracted from unheated coals identified as Rocky Mountain coal (RMC), Australian Gippsland Latrobe Eocene coal (GEC), Australian Gippsland Latrobe Cretaceous coal (GCC), and Texas Wilcox lignite (WL), as well as from pyrolysates obtained from heating of these coals. It was found that pentacyclic triterpanes are dominant in GEC, GCC, and WL, whereas diterpanes strongly predominate in the bitumen of RMC, indicating that resin is a more important constituent of RMC than of the other coals and that it releases the diterpenoids at an early stage of diagenesis. It was also found that the composition of diterpanes is different among these coals and that the distributions of sterane and triterpane in the natural bitumen of coals are very different from those of pyrolysates.

  13. Abundances of polycyclic aromatic hydrocarbons (PAHs) in 14 chinese and american coals and their relation to coal rank and weathering

    Science.gov (United States)

    Wang, R.; Liu, Gaisheng; Zhang, Jiahua; Chou, C.-L.; Liu, J.

    2010-01-01

    The abundances of 16 polycyclic aromatic hydrocarbons (PAHs) on the priority list of the United States Environmental Protection Agency (U.S. EPA) have been determined in 14 Chinese and American coals. The ranks of the samples range from lignite, bituminous coal, anthracite, to natural coke. Soxhlet extraction was conducted on each coal for 48 h. The extract was analyzed on a gas chromatograph-mass spectrometer (GC-MS). The results show that the total PAH content ranged from 0.31 to 57.6 ??g/g of coal (on a dry basis). It varied with coal rank and is highest in the maturity range of bituminous coal rank. High-molecular-weight (HMW) PAHs are predominant in low-rank coals, but low-molecular-weight (LMW) PAHs are predominant in high-rank coals. The low-sulfur coals have a higher PAH content than high-sulfur coals. It may be explained by an increasing connection between disulfide bonds and PAHs in high-sulfur coal. In addition, it leads us to conclude that the PAH content of coals may be related to the depositional environment. ?? 2010 American Chemical Society.

  14. The role of coal consumption in the economic growth of the Polish economy in transition

    Energy Technology Data Exchange (ETDEWEB)

    Henryk Gurgul; Lukasz Lach [AGH University of Science and Technology, Cracow (Poland). Department of Applications of Mathematics in Economics

    2011-04-15

    The main goal of this paper is an analysis of the causal links between quarterly coal consumption in the Polish economy and GDP. For the sake of accurate computation an additional variable - employment - was also taken into account. Computations conducted for the period Q1 2000 to Q4 2009 by means of recent causality techniques confirmed the neutrality of hard coal usage with respect to economic growth. On the other hand, calculations for the pairs lignite-GDP and total coal consumption-GDP showed the existence of a significant nonlinear causality from coal usage to economic growth. This is clear evidence for claiming that lignite plays an important role in the economic growth of the Polish economy. Furthermore, each coal-related variable was found to have a nonlinear causal impact on employment. Because of the relatively short length of available time series we additionally applied bootstrap critical values. The empirical results computed by both methods did not exhibit significant differences. These results have important policy implications. In general, our findings support the hypothesis that closing hard coal mines in Poland should have no significant repercussions on economic growth. However, this does not seem to be true for lignite mines. 42 refs., 1 fig., 11 tabs.

  15. Genetic relationship of flavenoids from extracts and semicoking tars of lignite with the initial vegetable matter

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Shrykin, A.Y.; Podshibyakin, S.I.; Proskuryakov, V.A.; Shavyrina, O.A. [Lev Tolstoi State Pedagogical University, Tula (Russian Federation)

    1999-06-01

    A genetic relationship of flavonoids from extracts and semi-coking tars of lignites mined at the near-Moscow and Kansk-Achinsk fields with flavenoids of vegetable origin has been found. Paleoreconstruction of the possible species of the initial vegetable matter from which the organic matter of these lignites had originated was performed. Possible schemes of transformations of the initial natural flavonoids under conditions of lignite formation and in the course of semicoking are presented.

  16. Chemical and toxicological evaluation of underground coal gasification (UCG) effluents. The coal rank effect.

    Science.gov (United States)

    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.

  17. STUDY ON DRYING UPGRADING AND FLOW CHARACTERISTIC OF LIGNITE IN VERTICAL PIPE DRYER%褐煤煤粉干燥立管提质干燥的流动特性研究

    Institute of Scientific and Technical Information of China (English)

    齐庆杰; 黄声和; 杨硕; 郭仁宁; 董子文

    2013-01-01

    Study on lignite coal powder in the drying process to mention the quality by which factors and how the factors are affected. Experimental data is used for the numerical simulation of the temperature, velocity and pressure fields by FLUENT6. 3. 26. It showed that lignite coal particles humidity changes when the brown one was upgrading and dry in low solid-gas ratio, and the results of upgrading and dry of the lignite is perfect; the drying effect of the pulverized coal had greatly improved when the inlet flue gas temperature was raised in the drying process, the flue gas velocity has little effect on the humidity of lignite powder particles.%通过实验研究褐煤煤粉在提质干燥过程受哪些因素的影响,利用FLUENT6.3.26对实验得到的数据进行温度、速度和压力场的数值模拟(气固两相流).对实验得到的数据和FLUENT6.3.26的数值模拟情况进行分析可知,褐煤煤粉在低气固比(体积比)进行提质干燥时,褐煤煤粉微粒的湿度有很大变化,提质干燥效果理想;在褐煤煤粉提质干燥过程中提高入口烟气温度,煤粉的干燥效果有很大提高;褐煤煤粉在提质干燥过程中烟气速度对褐煤粉颗粒湿度的影响很小.

  18. Petrology of Panandhro Lignite deposit, Gujarat in relation to palaeodepositional condition

    Energy Technology Data Exchange (ETDEWEB)

    Singh, A.; Singh, B.D. [Birbal Sahni Institute for Paleobotany, Lucknow (India)

    2005-09-01

    Petrological investigations on Early Eocene lignite from two mine sections of Block-1 in Panandhro Lignite field, under both normal incident (white) and fluorescence (blue light excitation) modes, reveal that deposit is rich in maceral huminite content with sub-ordinate amount of liptinite and low inertinite contents. The maceral composition indicates that sub-bituminous C lignites in both the mine sections are more or less similar with minor differences. Gelification and Tissue Preservation Indices suggest the deposition of lignite in lower delta plain environment in lagoonal conditions.

  19. Effect of biomass on burnouts of Turkish lignites during co-firing

    Energy Technology Data Exchange (ETDEWEB)

    Haykiri-Acma, H.; Yaman, S. [Istanbul Technical Univ., Chemical and Metallurgical Engineering Faculty, Chemical Engineering Dept., 34469 Maslak, Istanbul (Turkey)

    2009-09-15

    Co-firing of some low quality Turkish lignites with woody shells of sunflower seed was investigated via non-isothermal thermogravimetric analysis method. For this purpose, Yozgat-Sorgun, Erzurum-Askale, Tuncbilek, Gediz, and Afsin-Elbistan lignites were selected, and burnouts of these lignites were compared with those of their blends. Biomass was blended as much as 10 and 20 wt.% of the lignites, and heating was performed up to 900 C at a heating rate of 40 C/min under dry air flow of 40 mL/min. This study revealed that the same biomass species may have different influences on the burnout yields of the lignites. Burnouts of Erzurum-Askale lignite increased at any temperature with the increasing ratio of biomass in the blend, whereas burnout yields of other lignites decreased to some extent. Nevertheless, the blends of Turkish lignites with sunflower seed shell did not behave in very different way, and it can be concluded that they are compatible in terms of burnouts for co-combustion in a combustion system. Although the presence of biomass in the lignite blends caused to some decreases in the final burnouts, the carbon dioxide neutral nature of biomass should be taken into account, and co-combustion is preferable for waste-to-energy-management. (author)

  20. Radon concentrations in three underground lignite mines in Turkey.

    Science.gov (United States)

    Cile, S; Altinsoy, N; Celebi, N

    2010-01-01

    Monitoring of radon in underground mines is important in order to assess the radiological hazards to occupational workers. Radon concentration levels in three underground lignite mines (Tunçbilek, Omerler and Eynez) of Turkey were obtained in this study. For this reason, atmospheric radon level measurements were carried out in mines using CR-39 track detectors. Chemical etching of the detector tracks and subsequent counting were performed at Cekmece Nuclear Research and Training Center. The obtained results were evaluated according to the International Commission of Radiation Protection and the Turkish Atomic Energy Authority whose radon action levels for workplaces are 500-1500 and 1000 Bq(-3), respectively. The radon gas concentrations in the lignite mines were determined to be between 50 +/- 7 and 587 +/- 16 Bq m(-3). The results obtained in these experiments are far under the action levels. The computed radon doses for the mine workers of Tunçbilek, Omerler and Eynez lignite mines are 1.23, 2.44 and 1.47 mSv y(-1), respectively.

  1. Radon concentrations in three underground lignite mines in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Cile, S.; Altinsoy, N.; Celebi, N. [Istanbul Technical University, Istanbul (Turkey). Inst. of Energy

    2010-01-15

    Monitoring of radon in underground mines is important in order to assess the radiological hazards to occupational workers. Radon concentration levels in three underground lignite mines (Tuncbilek, Omerler and Eynez) of Turkey were obtained in this study. For this reason, atmospheric radon level measurements were carried out in mines using CR-39 track detectors. Chemical etching of the detector tracks and subsequent counting were performed at Cekmece Nuclear Research and Training Center. The obtained results were evaluated according to the International Commission of Radiation Protection and the Turkish Atomic Energy Authority whose radon action levels for workplaces are 500-1500 and 1000 Bq{sup -3}, respectively. The radon gas concentrations in the lignite mines were determined to be between 50 {+-} 7 and 587 {+-} 16 Bq m{sup -3}. The results obtained in these experiments are far under the action levels. The computed radon doses for the mine workers of Tuncbilek, Omerler and Eynez lignite mines are 1.23, 2.44 and 1.47 mSv y{sup -1}, respectively.

  2. Effects of low-temperature catalytic pretreatments on coal structure and reactivity in liquefaction. Final technical report, Volume 1 - effects of solvents, catalysts and temperature conditions on conversion and structural changes of low-rank coals

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Lili [Pennsylvania State Univ., University Park, PA (United States); Schobert, Harold H. [Pennsylvania State Univ., University Park, PA (United States); Song, Chunshan [Pennsylvania State Univ., University Park, PA (United States)

    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. For 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.

  3. Microbial conversion of coals to clean fuel forms

    Energy Technology Data Exchange (ETDEWEB)

    Barik, S.; Isbister, J.; Hawley, B.; Forgacs, T.; Reed, L.; Anspach, G.; Middaugh, T.

    1988-01-01

    Anaerobic cultures have been used for the production of methane and alcohols from coal. Cultures were adapted from natural inocula collected from sources such as sewage sludge and horse manure. A 1% (w/v) slurry of leonardite, lignite, or subbituminous coal was used in the incubations. Methane was produced from all cultures, including some untreated coals, to a greater extent than in control cultures. Over several months of adaptation, methane production capacity increased considerably. Volatile fatty acids (VFAs) were identified as intermediates in the conversion of coal to methane. A proposed scheme for the conversion is breakdown of the coal polymer by a series of organisms and metabolism of the fragments to methane precursors such as VFAs. A mixture of short chain alcohols was produced by cultures grown in the presence of methane inhibitors. These cultures after prolonged adaptation show potential for use in larger scale bioreactors for the production of gaseous and liquid fuels.

  4. Physical Cleaning of Lakhra Coal by Dense Medium Separation Method

    Directory of Open Access Journals (Sweden)

    Sikandar Ali Channa

    2015-07-01

    Full Text Available This research is an attempt to upgrade Lakhra Lignite Coal using ?Dense Medium Separation? technique, to make it techno-environmentally acceptable product for different industries. The air-dried samples of ROM (Run of Mine coal were crushed, screened, ground and subjected to initial analysis and specific gravity based sink-float tests. The initial analysis of air-dried samples shows the average values of moisture 19%, volatile matter 22.33%, ash 27.41%, fixed carbon 31.26% and sulphur 4.98%. The investigational results of sink-float analysis indicate that physical cleaning at particle size range from -5.6 to +0.3 mm and 75% clean coal recovery can potentially reduce the ash yield and sulphur content of Lakhra coal up to 41 and 42.4% respectively. This washed coal is techno-environmentally acceptable yield and simultaneously qualifies the quality parameters set by various industries of Pakistan

  5. Experimental study on pollution emission from combustion of blended coals

    Energy Technology Data Exchange (ETDEWEB)

    Li Yonghua; Chen Hongwei; Zhen Zhi; Liu Jizhen; Feng Zhaoxing; Dong Jianxun [North China Electric Power University, Baoding (China)

    2003-07-01

    The pollution brought by NOx and SOx produced by coal combustion is getting recognition by each country in the world. This paper adopts an experimental method, selects four kinds of lignite and three kinds of soft coal that are mainly used by some power plant and reports a study of the pollution emission characteristics of component and blended coals. The test rig is introduced from Canada with a capacity of 640 MJ/h with a complete milling system and flue gas online analysis system. The study focuses on the influence of oxygen concentration, pulverized coal fineness and pulverized coal nitrogen content on the pollution emission. The study is useful for achieving clean combustion in large power plants. 5 refs., 4 figs., 7 tabs.

  6. Co-pyrolysis of different type coals with hybrid poplar

    Energy Technology Data Exchange (ETDEWEB)

    Hanzade Haykiri-Acma; Serdar Yaman [Istanbul Technical University, Istanbul (Turkey). Dept. of Chemical Engineering

    2007-07-01

    The aim of this study is to investigate the co-pyrolysis characteristics of different rank coals such as peat, lignite, and anthracite in the presence of hybrid poplar. For this purpose, non-isothermal thermogravimetry technique was applied up to 900{sup o}C with a heating rate of 40{sup o}C/min under dynamic nitrogen flow of 40 mL/min. Hybrid poplar was added into each coal as much as 10 wt % of the coal sample and the experiments were repeated. Pyrolytic properties such as the char yields, gasification rates, and reactivity of the original samples and the blends were compared from the thermal analysis data, and interpreted. Addition of hybrid poplar to coal had some influences on the pyrolytic properties of coals that might be explained by the synergistic interaction approach. 15 refs., 3 figs., 4 tabs.

  7. Enteric virus removal inactivation by coal-based media

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, A.; Chaudhuri, M. [Indian Institute of Technology, Kanpur (India). Dept. of Civil Engineering

    1995-02-01

    Four coal-based media, viz. alum-pretreated or ferric hydroxide-impregnated Giridih bituminous coal and lignite (alum-GBC, Fe-GBC; alum-lignite and Fe-Lignite) were laboratory tested to assess their potential in removing/inactivating enteric viruses in water. Batch-sorption screening tests, employing a poliovirus-spiked canal water, indicated high poliovirus sorption by Fe-GBC and alum-GBC in a short contact time of 5 min. Based on the results of further batch-sorption tests, using silver incorporated media (alum/Ag-GBC, alum-GBC-Ag and Fe-GBC-Ag), as well as aesthetic water quality consideration and previous findings on removal of coliforms and turbidity, alum/Ag-GBC, alum-GBC and alum-GBC-AG were included in downflow column studies employing poliovirus-spiked canal water. All three media showed potential in removing/inactivating enteric viruses. In a separate column study employing a joint challenge of poliovirus and rotavirus, alum/Ag-GBC removed 59.3-86.5% of the viruses along with more than 99% reduction in indigenous heterotrophic bacteria. Alum/silver-pretreated bituminous coal medium appears promising for use in household water filters in rural areas of the developing world. However, improved medium preparation to further enhance its efficiency is needed; also, its efficacy in removing/inactivating indigenous enteric bacteria, viruses and protozoa has to be ensured and practicalities or economics of application need to be considered.

  8. Non-enzymatic depolymerization of cotton cellulose by fungal mimicking metabolites

    DEFF Research Database (Denmark)

    Hastrup, Anne Christine Steenkjær; Howell, Caitlin; Jensen, Bo

    2011-01-01

    peroxide, iron, and oxalic acid. The former two are involved in the Fenton reaction in which they react to form hydroxyl radicals, which cause an accelerated depolymerization in cotton cellulose. We found the same reaction to be caused by both iron Fe3+ and Fe2+. A 10 mM oxalic acid solution showed...... significant depolymerization effect on cotton cellulose. An oxalic acid/sodium oxalate buffered pH gradient had an inhibitory effect on the reduction of cellulose polymers at increased pH values. The organic iron chelator, EDTA, was found to promote depolymerization of cellulose in combination with Fenton......’s reagents, but inhibited the effect of oxalic acid in the absence of iron and hydrogen peroxide. Manganese was tested to see if metals other than iron could generate a significant impact on the degree of polymerization (DP) in cotton cellulose. Depolymerizing properties comparable to iron were seen...

  9. Depolymerization of Poly(bisphenol A carbonate) in Subcritical and Supercritical Toluene

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The depolymerization of poly(bisphenol A carbonate)(PC) in subcritical and supercritical toluene was studied. The experimental parameters, which influence the depolymerization reaction such as temperature (570-633 K), pressure (4.0-7.0 MPa), reaction time (5-60 min), and toluene to PC weight ratio (3.0-11.0), were investigated, and the reaction products were determined by GC, GC/MS and FT-IR spectrometer. It was found that the main product of the depolymerization reaction was bisphenol A(BPA). BPA accounted for over 55.7% of the depolymerization products at reaction temperature 613 K, pressure 5.0-6.0 MPa, reaction time 15 min and toluene/PC weight ratio of around 7.0.

  10. Analysis of the liquefied and solubilized coals by the action of microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Luna, N.; Fernandez, M.; Monistrol, I.F.; Laborda, F. [Madrid Univ. (Spain). Dept. de Microbiologia y Parasitologia

    1997-12-31

    The analysis of liquefied/solubilized products from lignite by microorganisms showed some alterations in the chemical composition with regard to the original coal. Noteworthy, a reduction in the average molecular weight and an increase in the condensation index of humic acids derived from the liquid lignite were observed. These results could indicate that microorganisms degrade the humic acids to rend them more suitable as microbial nutrients. The observation that microorganisms could use humic acids as the only carbon source supported this supposition. (orig.)

  11. Geochemical characteristics of different maceral groups in the Huangxian Coal,China

    Institute of Scientific and Technical Information of China (English)

    CAI Zhen-yu; WANG Jin-xi; JIN Yu-jie; ZHANG Hong-jian; JIN Kan-kun

    2004-01-01

    In order to research how lignite is utilized, two coal samples of seams 2 and 4were taken from the Huangxian Basin, China. The samples were separated into vitrinite,sporinite, and resinite. Geo-chemical and pyrolysis methods were used to analyse three maceral groups and two seam samples. The results indicate that the resinite and sporinite groups have higher extract yields, S1, S2, HI values, and pyrolysis compounds.These differences may shed light on the usage of the Huangxian lignite. Seam 2 produces more gas and oil than seam 4 does because seam 2 contains more resinite and sporinite macerals.

  12. Nitrogen release during coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, L.L.; Mitchell, R.E.; Fletcher, T.H.; Hurt, R.H.

    1995-02-01

    Experiments in entrained flow reactors at combustion temperatures are performed to resolve the rank dependence of nitrogen release on an elemental basis for a suite of 15 U.S. coals ranging from lignite to low-volatile bituminous. Data were obtained as a function of particle conversion, with overall mass loss up to 99% on a dry, ash-free basis. Nitrogen release rates are presented relative to both carbon loss and overall mass loss. During devolatilization, fractional nitrogen release from low-rank coals is much slower than fractional mass release and noticeably slower than fractional carbon release. As coal rank increases, fractional nitrogen release rate relative to that of carbon and mass increases, with fractional nitrogen release rates exceeding fractional mass and fractional carbon release rates during devolatilization for high-rank (low-volatile bituminous) coals. At the onset of combustion, nitrogen release rates increase significantly. For all coals investigated, cumulative fractional nitrogen loss rates relative to those of mass and carbon passes through a maximum during the earliest stages of oxidation. The mechanism for generating this maximum is postulated to involve nascent thermal rupture of nitrogen-containing compounds and possible preferential oxidation of nitrogen sites. During later stages of oxidation, the cumulative fractional loss of nitrogen approaches that of carbon for all coals. Changes in the relative release rates of nitrogen compared to those of both overall mass and carbon during all stages of combustion are attributed to a combination of the chemical structure of coals, temperature histories during combustion, and char chemistry.

  13. Thermal depolymerization of plastics - PDU testing. Task 15. Topical report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-01-01

    The process development unit (PDU) test program is part of an ongoing effort at the Energy & Environmental Research Center (EERC) to expand the base of knowledge for the thermal depolymerization of plastics process. This phase of the development effort, initiated after successful completion of a bench-scale program, has concentrated on maximizing liquid yield. The purposes of the PDU program were (1) to demonstrate the process on a commercially scalable unit, (2) to produce quantities of product that could be used to initiate discussions with potential end users, and (3) to gather engineering and yield data. Experimentation consisted of eleven test points on the PDU and seven on the continuous fluid-bed reactor (CFBR) bench-scale unit. Initial PDU tests (PO35-PO39) were carried out using a base blend, which consists of 60% high-density polyethylene (HDPE), 20% polypropylene (PP), and 20% polystyrene (PS) virgin resin pellets. Test PO39 used base blend with 5% polyvinyl chloride (PVC). The base blend decomposed to produce a flowable liquid, with liquid yields ranging from 33% to 45%. The next series of tests, PO40-PO44, used a postconsumer plastics feed. This material did not decompose as readily as the base blend and formed a very waxy, heavy liquid, with {open_quotes}liquid{close_quotes} yields ranging from 18% to 63% (low liquid yields are the result of using excess air in the natural gas burner in some tests in an attempt to increase gas residence time).

  14. Material balance in coal. 2. Oxygen determination and stoichiometry of 33 coals

    Energy Technology Data Exchange (ETDEWEB)

    Volborth, A.; Miller, G. E.; Garner, C. K.; Jerabek, P. A.

    1977-07-20

    The chemical analysis of coal can be supplemented by the determination of oxygen in high and low temperature ash, in coal as received and in coal dried at 105/sup 0/C. The rapid method utilizes fast-neutron activation. The reaction /sup 16/O(n,p)/sup 16/N and counting of the 6.1 and 7.1 MeV gammas of 7.3 second half-life are used. A specially designed dual transfer and simultaneous counting system gives very accurate results. Oxygen in 33 coals ranging from lignite to low volatile bituminous coal is determined and compared with ''oxygen by difference.'' Considerable discrepancies are observed. Better stoichiometric results are obtained if oxygen in coal ash, in wet coal and in the dried coal is determined. This permits the estimation of the true material balances using data of the ultimate and the proximate coal analysis. The oxygen determination provides the coal chemist with an accurate basis and can be used to rank coal. The summation of the percent of carbon, nitrogen, hydrogen, sulfur, and oxygen becomes more meaningful and some errors can be detected and the state of completeness of coal analysis thus evaluated. Total sulfur can be estimated and oxidation effects during drying can be detected. These affect the moisture determination. It appears that after more data are collected, the interpretation of solid fuel analyses may be facilitated and will be stoichiometrically more meaningful. It is shown that it may be possible to simplify the present time-consuming methods of coal analysis.

  15. Coking coals of Mongolia: Distribution and resources

    Science.gov (United States)

    Erdenetsogt, Bat-Orshikh; Jargal, Luvsanchultem

    2016-04-01

    The coal deposits of Mongolia tend to become younger from west to east and can be subdivided into two provinces, twelve basins, and three areas. Main controlling factor of coal rank is the age of coal bearing sequences. Western Mongolian coal-bearing province contains mostly high rank bituminous coal in strata from Late Carboniferous. The basins in southern Mongolia and the western part of central Mongolia have low rank bituminous coal in strata from the Permian. The northern and central Mongolian basins contain mainly Jurassic subbituminous coal, whereas the Eastern Mongolian province has Lower Cretaceous lignite. Mongolian known coking coal reserves are located in western, southern and northern Mongolia and related to Carboniferous, Permian and Jurassic sequences, respectively. Pennsylvanian Nuurstkhotgor coal deposit is located in northwestern Mongolia (in Western Mongolian coal-bearing province). The coals have 1-7.5 crucible swelling number (CSN) and 0-86 G-index. Vitrinite reflectance value (Rmax in oil) varies from 0.7% to 1.2% and sulfur content is low, ranging from 0.3% to 0.6% with an average of 0.4%. Coal reserve is estimated to be 1.0 billion ton, of which half is coking coal. Upper Permian Khurengol deposit is situated in western Mongolia (in Western Mongolian coal-bearing province). CSN and G-index of coal are 8-9 and 54-99, respectively. The coals have Rmax of 1.1 to 1.7% (average 1.4%) and sulfur content of 0.2 to 0.6% (average 0.4%). Coking coal reserve of the deposit is estimated to be 340 million ton. Upper Permian Tavantolgoi, the largest coking coal deposit, lies in southern Mongolia (in South Gobi coal-bearing basin). The coals have CSN of 1 to 7.5 and Rmax of 0.7% to 1.2%. Sulfur content is low, ranging from 0.5% to 0.9%. Coal reserve is estimated to be 6.0 billion ton, of which 2.0 billion ton is accounted as coking coal. Lower-Middle Jurassic Ovoot coal is located in northern Mongolia (in Orkhon-Selenge coal-bearing area). This is one of

  16. Basic problems which are being solved at the mining and power producting economic association im. G. Dimitrov, increasing coal reserves and implementing measures to prevent a deterioration in the quality of the coal

    Energy Technology Data Exchange (ETDEWEB)

    Stoimenov, St.; Gonev, Iv.

    1984-01-01

    The mining and power producing economic association im. G. Dimitrov delivers 17.5 percent of all the coal extracted in Bulgaria (NRB). 57.68 percent brown coal, 7.2 percent lignite and 100 percent of the anthracite for the entire country are extracted here. The quality of the coal is low. According to the cited data, the reserves of coal in the basin are 143 million tons, which, with a mean annual extraction of 6 million tons, will support operation of the mines to and after the year 2010. The ash content of the coals is high and is 58.6; 42 and 40 percent, respectively, for the brown coal, the lignite and the anthracites. An increase in the reserves of the Perishkiy basin was accomplished as a result of a number of measures: deblocking of the coal reserves located under major structures and buildings; expansion of open pit mining in depth and strike; reevaluation of the thin and high ash content strata in the reserves for extraction, additional explorations and so on. There are constantly ongoing measures to maintain and increase the quality of the extracted coal due to the continuous reduction in the quality of the coal reserves. The existing weaknesses and deficiencies are listed, along with measures to overcome them. The ash content in the commercial coal was reduced by 0.85 percent for 1983 as compared to the previous year, and by 1 percent for the brown coals as a result of these measures.

  17. Acidification - neutralization processes in a lignite mine spoil amended with fly ash or limestone

    Energy Technology Data Exchange (ETDEWEB)

    Seoane, S.; Leiros, M.C. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain). Dept. de Edafologia y Quimica Agricola

    2001-08-01

    A laboratory experiment was conducted to investigate the long-term effects of amending sulfide-rich lignite mine spoil with fly ash (originating from a coal-fired power station and largely comprised of aluminosilicates) and/or agricultural limestone. The experiment was carried out with soil moisture maintained at field capacity or alternate cycles of wetting and drying. Results obtained suggest that the principal acidification processes were oxidation of sulfide and formation of hydroxysulfate (FeOHSO{sub 4}), whereas the main neutralization processes were weathering of aluminosilicates in fly ash-treated samples. The highest dose of limestone rapidly raised the pH of the spoil, but this increase was not maintained throughout the one-year experiment. In contrast, fly ash-treated samples showed a more sustained increase in pH, attributable to the gradual weathering of aluminosilicates. The best results (i.e., good short- and long-term neutralization) were obtained in samples treated with both fly ash and limestone. The low liming capacity of the fly ash (47.85 cmol kg{sup -1}) means that it must be used in large quantities, an advantage in achieving the further aim of disposing of the fly ash. 33 refs., 5 figs., 4 tabs.

  18. Conversion of solvent refined lignite into premium liquid fuels. Annual report, January-December, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Baltisberger, R.J.; Stenberg, V.I.; Klabunde, K.J.; Woolsey, N.F.

    1981-04-01

    Comparison of three preasphaltene samples separated from three lignite derived samples obtained from GFETC prepared at 404, 460 and 480/sup 0/C shows that increased temperature tends to produce higher molecular weight preasphaltene fractions containing more aromatic carbons with fewer acid (phenolic) sites per molecule. Ether cleavage studies of the model compounds; diphenyl ether, bibenzothiophene, dibenzofuran and anisole, show that partial or complete ether cleavage was obtained with sodium in hexamethyl phosphoramide solvent. Thus a careful consideration of acidity before and after cleavage can now give a measure of the diaryl ether content of a mixture. This reaction may be useful in coal liquid analysis. Denitrification of N,N-Dimethylamine without aromatic ring reduction occurs with CO-H/sub 2/O and H/sub 2/ at 425/sup 0/C in about 13% conversion. The optimum of 21 conditions gave a 19% conversion which occurs at 150 psi H/sub 2/S and 750 psi H/sub 2/. Thus, H/sub 2/S enhances nitrogen removal from this model compound. Using ESR dispersion techniques we have shown the presence of a second CO radical species on MgO, probably CO-.. observed by ESR, treatment of carbon monoxide radical species on both CO and MgO with CO/sub 2/ or H/sub 2/O causes a destruction of one of the radical species at a rate greater than that of the other.

  19. Lignitic Humic Acids as Environmentally-Friendly Adsorbent for Heavy Metals

    Directory of Open Access Journals (Sweden)

    Martina Klučáková

    2017-01-01

    Full Text Available Humic acids are a part of humus material, are abundant in nature, and form a substantial pool of natural organic matter. They participate in the transport of both beneficial and harmful species. Due to their structure and properties, they can interact with metal ions and, with them, form relatively stable complexes. These substances are thus responsible for the so-called self-cleaning ability of soils. Lignite as a young coal type contains a relatively high amount of humic acids which can be used as an environmentally-friendly adsorbent for heavy metals. In this work, we compared the adsorption of single Cu2+ ions with the simultaneous adsorption of several different metal ions (Cd2+, Cu2+, Pb2+, and Zn2+. The adsorption efficiency of humic acids was very high, almost 100% in the case of the single adsorption of Cu2+ ions and more than 90% for the adsorption from the mixture of metal ions. The stability of formed complexes, considered on the basis of the leaching in different extraction agents, was higher than 80%; only 9–18% was in the mobile phase. After adsorption, metal ions are contained in humic acids after adsorption in mainly strongly bonded form (60–73% and can be liberated from their structure only in low amounts.

  20. Genetic relationship of organic bases of the quinoline and isoquinoline series from lignite semicoking tars with the initial biological material

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Proskuryakov, V.A.; Podshibyakin, S.I.; Domogatskii, V.V.; Shvykin, A.Y.; Shavyrina, O.A.; Chilachava, K.B. [Leo Tolstoy State Pedagog University, Tula (Russian Federation)

    2002-07-01

    The genetic relationship of quinoline and isoquinoline compounds present in semicoking tars of Kimovsk lignites (near-Moscow fields) with the initial vegetable material is discussed. Transformation pathways of the native compounds in the course of lignite formation are suggested.

  1. XRD and FT–IR investigations of sub-bituminous Assam coals

    Indian Academy of Sciences (India)

    Binoy K Saikia; R K Boruah; P K Gogoi

    2007-08-01

    Two coal samples collected from Makum coal field, Assam, India were studied by XRD and FT–IR techniques. The X-ray diffractogram shows the existence of some crystalline carbons in Assam coals as proven by the appearance of peaks. The radial distribution functional (RDF) method was applied for the determination of structural aspects of the coals. The study indicates that the coals are lignite in type and there is no evidence of graphite-like structures. The maximum in the () plots of function of radial distribution of atoms (FRDA) relates to different distances between carbon atoms of aliphatic chains. The first significant maximum relates to the C–C bond (type C–CH=CH–C), the second maximum relates to the distance between carbon atoms of aliphatic chains that are located across one carbon atom. The curve intensity profiles obtained from FRDA show quite regular molecular packets for this coal. The coals were found to be lignite in nature. FT–IR study shows the presence of aliphatic carbon, C=O and C–O stretching associated with –OH and –NH stretching vibrations. Kaolinite and quartz were also found to be major minerals in Assam coals by FTIR spectroscopy. The difference in intensities of carbonyl groups of the coal samples is likely to relate with the rank.

  2. XRD and FT-IR investigations of sub-bituminous Assam coals

    Energy Technology Data Exchange (ETDEWEB)

    Saikia, B.K.; Boruah, R.K.; Gogoi, P.K. [Tezpur University, Tezpur (India). Dept. of Chemical Science

    2007-08-15

    Two coal samples collected from Makum coal field, Assam, India were studied by XRD and FT-IR techniques. The X-ray diffractogram shows the existence of some crystalline carbons in Assam coals as proven by the appearance of peaks. The radial distribution functional (RDF) method was applied for the determination of structural aspects of the coals. The study indicates that the coals are lignite in type and there is no evidence of graphite-like structures. The maximum in the Gr) plots of function of radial distribution of atoms (FRDA) relates to different distances between carbon atoms of aliphatic chains. The first significant maximum relates to the C-C bond (type C-CH=CH-C), the second maximum relates to the distance between carbon atoms of aliphatic chains that are located across one carbon atom. The curve intensity profiles obtained from FRDA show quite regular molecular packets for this coal. The coals were found to be lignite in nature. FT-IR study shows the presence of aliphatic carbon, C=O and C-O stretching associated with -OH and -NH stretching vibrations. Kaolinite and quartz were also found to be major minerals in Assam coals by FTIR spectroscopy. The difference in intensities of carbonyl groups of the coal samples is likely to relate with the rank.

  3. Simultaneous quantification of depolymerization and mineralization rates by a novel 15N tracing model

    Science.gov (United States)

    Andresen, Louise C.; Björsne, Anna-Karin; Bodé, Samuel; Klemedtsson, Leif; Boeckx, Pascal; Rütting, Tobias

    2016-09-01

    The depolymerization of soil organic matter, such as proteins and (oligo-)peptides, into monomers (e.g. amino acids) is currently considered to be the rate-limiting step for nitrogen (N) availability in terrestrial ecosystems. The mineralization of free amino acids (FAAs), liberated by the depolymerization of peptides, is an important fraction of the total mineralization of organic N. Hence, the accurate assessment of peptide depolymerization and FAA mineralization rates is important in order to gain a better process-based understanding of the soil N cycle. In this paper, we present an extended numerical 15N tracing model Ntrace, which incorporates the FAA pool and related N processes in order to provide a more robust and simultaneous quantification of depolymerization and gross mineralization rates of FAAs and soil organic N. We discuss analytical and numerical approaches for two forest soils, suggest improvements of the experimental work for future studies, and conclude that (i) when about half of all depolymerized peptide N is directly mineralized, FAA mineralization can be as important a rate-limiting step for total gross N mineralization as peptide depolymerization rate; (ii) gross FAA mineralization and FAA immobilization rates can be used to develop FAA use efficiency (NUEFAA), which can reveal microbial N or carbon (C) limitation.

  4. Amination of biorefinery technical lignins using Mannich reaction synergy with subcritical ethanol depolymerization.

    Science.gov (United States)

    Wang, Bing; Chen, Tian-Ying; Wang, Han-Min; Li, Han-Yin; Liu, Chuan-Fu; Wen, Jia-Long

    2017-09-06

    The alcoholic depolymerization and Mannich reaction were conducted to improve the chemical activity of biorefinery technical lignins and introduce amino groups into lignins, respectively. To understand the chemical structural transformations and examine the reaction mechanism, GPC and solution-state NMR techniques were performed. Element analysis was also used to quantify the amount of amine groups. The NMR characterization the depolymerized lignins indicated of the depolymerization, demethoxylation, and bond cleavage of linkages occurred during the depolymerization process. Results showed that the depolymerization temperature instead of the addition of capping reagents was the main factor for improving the reactivity of lignin under the given conditions. The Mannich reaction was very selective, primarily occurred at H3,5 and G5 positions, and the H units present a higher chemical reactivity. It is believed that the understanding of the fundamental chemistry of lignin during depolymerization and Mannich reaction process will contribute to the extension of high value-added applications of biorefinery lignin. Copyright © 2017. Published by Elsevier B.V.

  5. New directions in the work of the Institute on Industrial Chemistry in the coal-tar chemical industry

    Energy Technology Data Exchange (ETDEWEB)

    Lisicki, Z.

    1983-01-01

    This is a survey of works by the Institute on Industrial Chemistry (Warsaw) in the area of new coal treatment processes (particularly lignite) in chemical raw material by extraction in supercritical conditions and by hydrocracking of extracts. A number of new methods for the chemical use of the coke resin and its components are described.

  6. Development of biological coal gasification (MicGAS process). Final report, May 1, 1990--May 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-31

    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 the 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.

  7. Organic geochemistry of Amynteo lignite deposit, northern Greece: a Multi-analytical approach

    NARCIS (Netherlands)

    Iordanidis, A.; Schwarzbauer, J.; Georgakopoulos, A.; Lagen, van B.

    2012-01-01

    Several lignite samples were collected from boreholes of the Amynteo opencast lignite mine, northern Greece. Organic geochemical characteristics were investigated with the help of various analytical techniques, comprising Gas Chromatography (GC) and Gas-chromatography-Mass Spectrometry (GC-MS), Four

  8. Thermocatalytical processing of coal and shales

    Directory of Open Access Journals (Sweden)

    Zhaksyntay Kairbekov

    2012-12-01

    Full Text Available The article investigates the questions of thermocatalytical conversion of organic mass of coal (OMC, it is shown that in the absence of a catalyst process is carried out by a radical process. Accumulated data on the properties for radicals of different structure and therefore different reaction capacity enables us to understand and interpret the conversion of OMC. Thermal conversion of OMC regarded as a kind of depolymerization, accompanied by decomposition of the functional groups with the formation of radicals, competing for hydrogen atom. Catalyst can change the direction and conditions of the process. Modern catalysts can reduce the process pressure up to 50 atm., with a high degree of coal conversion. We consider examples of simultaneous conversion of coal and shale, shale and masut, shale and tar.

  9. TOXIC SUBSTANCES FROM COAL COMBUSTION

    Energy Technology Data Exchange (ETDEWEB)

    A KOLKER; AF SAROFIM; CL SENIOR; FE HUGGINS; GP HUFFMAN; I OLMEZ; J LIGHTY; JOL WENDT; JOSEPH J HELBLE; MR AMES; N YAP; R FINKELMAN; T PANAGIOTOU; W SEAMES

    1998-12-08

    The Clean Air Act Amendments of 1990 identify a number of hazardous air pollutants (HAPs) as candidates for regulation. Should regulations be imposed on HAP emissions from coal-fired power plants, a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion will be needed. With support from the Federal Energy Technology Center (FETC), the Electric Power Research Institute, the Lignite Research Council, and VTT (Finland), Physical Sciences Inc. (PSI) has teamed with researchers from USGS, MIT, the University of Arizona (UA), the University of Kentucky (UK), the University of Connecticut (UC), the University of Utah (UU) and the University of North Dakota Energy and Environmental Research Center (EERC) to develop a broadly applicable emissions model useful to regulators and utility planners. The new Toxics Partitioning Engineering Model (ToPEM) will be applicable to all combustion conditions including new fuels and coal blends, low-NO combustion systems, and new power generation x plants. Development of ToPEM will be based on PSI's existing Engineering Model for Ash Formation (EMAF). This report covers the reporting period from 1 July 1998 through 30 September 1998. During this period distribution of all three Phase II coals was completed. Standard analyses for the whole coal samples were also completed. Mössbauer analysis of all project coals and fractions received to date has been completed in order to obtain details of the iron mineralogy. The analyses of arsenic XAFS data for two of the project coals and for some high arsenic coals have been completed. Duplicate splits of the Ohio 5,6,7 and North Dakota lignite samples were taken through all four steps of the selective leaching procedure. Leaching analysis of the Wyodak coal has recently commenced. Preparation of polished coal/epoxy pellets for probe/SEM studies is underway. Some exploratory mercury LIII XAFS work was

  10. Cooperative research in coal liquefaction infratechnology and generic technology development: Final report, October 1, 1985 to December 31, 1986

    Energy Technology Data Exchange (ETDEWEB)

    Sendlein, L.V.A.

    1987-06-29

    During the first year of its research program, the Consortium for Fossil Fuel Liquefaction Science has made significant progress in many areas of coal liquefaction and coal structure research. Research topics for which substantial progress has been made include integrated coal structure and liquefaction studies, investigation of differential liquefaction processes, development and application of sophisticated techniques for structural analysis, computer analysis of multivariate data, biodesulfurization of coal, catalysis studies, co-processing of coal and crude oil, coal dissolution and extraction processes, coal depolymerization, determination of the liquefaction characteristics of many US coals for use in a liquefaction database, and completion of a retrospective technology assessment for direct coal liquefaction. These and related topics are discussed in considerably more detail in the remainder of this report. Individual projects are processed separately for the data base.

  11. Depositional conditions of the coal-bearing Hirka Formation beneath Late Miocene explosive volcanic products in NW central Anatolia, Turkey

    Indian Academy of Sciences (India)

    Mehmet Şener

    2007-04-01

    This work focuses on the relationship between the coal deposition and explosive volcanism of the Miocene basin, NW central Anatolia, Turkey. The coal-bearing Hirka Formation was deposited over the Galatian Andesitic Complex and/or massive lagoonal environments during the Miocene. The investigated lignite is a high ash (from 32 to 58%) and sulphur (from 1.43 to 3.03%) lignite which is petrographically characterised by a high humunite content. The mineral matter of the studied lignite samples is made up of mainly clay minerals (illite–smectite and kaolinite), plagioclase and quartz in Bolu coal field, clay minerals (illite–smectite, smectite and illite), quartz, calcite, plagioclase and gypsum in Seben coal field, quartz, K-feldspar, plagioclase and clay minerals (kaolinite and illite) in Kıbrıscık, and dolomite, quartz, clinoptilolite, opal CT and gypsum in C¸ amlıdere coal field. The differences in these four types of lignite with specific mineralogical patterns may be due to the explosive volcanic events and depositional conditions which changed from one coal field to the others. There is a zonation from SW to SE in the studied area for zeolites such as Opal CT+smectite-clinoptilolite-analcime-K-feldspar. Carbonate minerals are commonly calcite in Seben and Kıbrıscık coal fields. In Bolu, coal samples are devoid of calcite and dolomite. These analyses show that there is an increase in the amount of Mg and a decrease in the amount of Na from the northwestern part to the southern part in the study area.

  12. Growth response of container-grown plants in potting media amended with lignite

    Energy Technology Data Exchange (ETDEWEB)

    Kamp, M.

    1983-01-01

    A peat-vermiculite (50/50 v/v) potting medium was amended with 25 or 33% lignite by volume to determine if this could be used as a major media component for the culture of several greenhouse crops. Lignite-amended media did not alter the growth parameters of Pelargonium at 25 and 33% lignite. With 25% lignite Philodendron selloum grew as well as controls but at 33% growth was reduced and the leaves exhibited some phytotoxocity. Ficus benjamina, Ardisia humilis, poinsettias and Chrysanthemum morifolium responded poorly to lignite-amended media and leaf phytotoxicity was observed on plants with reduced growth. Leaf phytotoxicity in Chrysanthemum and Philodendron was not related to an excess of minor element content in the leaves. 3 references.

  13. Palaeoenvironmental reconstruction of Hüsamlar coal seam, SW Turkey

    Indian Academy of Sciences (India)

    Zeynep Büçkün; HüLya İnaner; Riza Görkem Oskay; Kimon Christanis

    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.

  14. Iron mineralogy across the oxycline of a lignite mine lake

    OpenAIRE

    Miot, Jennyfer; Lu, Shipeng; Morin, Guillaume; Adra, Areej,; Benzerara, Karim; Küsel, Kirsten

    2016-01-01

    International audience; Iron-rich pelagic aggregates of microbial origin named “iron snow” are formed in the water column of some acidic lignite mine lakes. We investigated the evolution of Fe mineralogy across the oxycline of the Lusatian lake 77, Germany at two sampling sites differing by their pH and mixing profiles. The central basin (CB) of this lake shows a dimictic water regime with a non-permanent anoxic deep layer and a homogeneous acidic pH all over the water column (pH 3). In contr...

  15. Co-pyrolysis of lignite with hazelnut shell

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Haykiri-Acma, H. [Istanbul Technical University, Istanbul (Turkey). Chemical Engineering Department

    2005-07-01

    In this study, the formation rates of the apparent pyrolytic products of Elbistan lignite sample from Turkey and Turkish hazelnut shell were investigated. For this purpose, original samples and their blends were subjected to pyrolysis process using a thermogravimetric analyzer under a dynamic nitrogen atmosphere of 40 cc/min. Temperature was increased from ambient to 1173 K with a heating rate of 20 K/min. Derivative thermogravimetric analysis curves were obtained, by which the rates of pyrolysis process at different temperatures were evaluated. 8 refs., 3 figs., 2 tabs.

  16. Oxydesulfurization of a Turkish hard lignite with ammonia solutions

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Kuecuekbayrak, S. [Istanbul Technical Univ. (Turkey). Chemical and Metallurgical Engineering Faculty

    1996-09-01

    In this study the desulfurization of a high pyritic and high organic sulfur lignite taken from the Gediz area (western Turkey) was investigated by the oxydesulfurization method using ammonia solutions. The influence of such parameters as the concentration of ammonia solution, partial pressure of oxygen, temperature, and reaction time were studied. The ranges of these parameters were selected as 0--10 M concentration of ammonia solution, 0--1.5 MPa partial pressure of oxygen, 403--473 K temperature, and 10--60 min reaction time. It was concluded that the use of ammonia solution as an extraction solution increased the efficiency of the oxydesulfurization process.

  17. A comparison between alkaline and decomplexing reagents to extract humic acids from low rank coals

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, D.; Cegarra, J.; Abad, M. [CSIC, Madrid (Spain). Centro de Edafologia y Biologia Aplicada del Segura

    1996-07-01

    Humic acids (HAs) were obtained from two low rank coals (lignite and leonardite) by using either alkali extractants (0.1 M NaOH, 0.1 M KOH or 0.25 M KOH) or solutions containing Na{sub 4}P{sub 2}O{sub 7} (0.1 M Na{sub 4}P{sub 2}O{sub 7} or 0.1 M NaOH/Na{sub 4}P{sub 2}O{sub 7}). In both coals, the greatest yields were obtained with 0.25 M KOH and the lowest with the 0.1 M alkalis, whereas the extractions based on Na{sub 4}P{sub 2}O{sub 7} yielded intermediate values and were more effective on the lignite. Chemical analysis showed that the leonardite HAs consisted of molecules that were less oxidized and had fewer functional groups than the HAs released form the lignite. Moreover, the HAs extracted by reagents containing Na{sub 4}P{sub 2}O{sub 7} exhibited more functional groups than those extracted with alkali, this effect being more apparent in lignite because of its greater cation exchange capacity. Gel permeation chromatography indicated that the leonardite HAs contained a greater proportion of higher molecular size compounds than the lignite HAs, and that both solutions containing Na{sub 4}P{sub 2}O{sub 7} released HAs with a greater proportion of smaller molecular compounds from the lignite than did the alkali extractants. 16 refs., 3 figs., 2 tabs.

  18. Temperatures of coal particle during devolatilization in fluidized bed combustion reactor

    Energy Technology Data Exchange (ETDEWEB)

    Komatina, M.; Manovic, V.; Saljnikov, A. [University of Belgrade, Belgrade (Serbia). Faculty of Mechanical Engineering

    2006-11-15

    The purpose of this study was to investigate the thermal behavior of coal during devolatilization in fluidized bed. Temperatures in the center of single coal particle were measured by thermocouple. Two coals were tested (brown coal Bogovina and lignite Kosovo), using dry coal particle, shaped into spherical form of diameters 7 and 10 mm, in temperature range from 300 to 850{sup o}C. Unsteady behavior of coal particle during heating and devolatilization in fluidized bed was described by a model that takes into account heat transfer between bed and particle surface, heat transfer through particle and an endothermic chemical reaction of first-order. Based on the mathematical model analysis and compared with experimental results, values of heat conductivity {lambda}{sub C} and heat capacity (C-p) of coal were determined. The best agreement was obtained for constant thermal properties, for brown coal {lambda}{sub C} = 0.20 W/mK and C{sub p} = 1200 J/kgK and for lignite {lambda}{sub C} = 0.17 W/mK and C-p = 1100 J/kgK.

  19. Mercury Control for Plants Firing Texas Lignite and Equipped with ESP-wet FGD

    Energy Technology Data Exchange (ETDEWEB)

    Katherine Dombrowski

    2009-12-31

    This report presents the results of a multi-year test program conducted as part of Cooperative Agreement DE-FC26-06NT42779, 'Mercury Control for Plants Firing Texas Lignite and Equipped with ESP-wet FGD.' The objective of this program was to determine the level of mercury removal achievable using sorbent injection for a plant firing Texas lignite fuel and equipped with an ESP and wet FGD. The project was primarily funded by the U.S. DOE National Energy Technology Laboratory. EPRI, NRG Texas, Luminant (formerly TXU), and AEP were project co-funders. URS Group was the prime contractor, and Apogee Scientific and ADA-ES were subcontractors. The host site for this program was NRG Texas Limestone Electric Generating Station (LMS) Units 1 and 2, located in Jewett, Texas. The plant fires a blend of Texas lignite and Powder River Basin (PRB) coal. Full-scale tests were conducted to evaluate the mercury removal performance of powdered sorbents injected into the flue gas upstream of the ESP (traditional configuration), upstream of the air preheater, and/or between electric fields within the ESP (Toxecon{trademark} II configuration). Phases I through III of the test program, conducted on Unit 1 in 2006-2007, consisted of three short-term parametric test phases followed by a 60-day continuous operation test. Selected mercury sorbents were injected to treat one quarter of the flue gas (e.g., approximately 225 MW equivalence) produced by Limestone Unit 1. Six sorbents and three injection configurations were evaluated and results were used to select the best combination of sorbent (Norit Americas DARCO Hg-LH at 2 lb/Macf) and injection location (upstream of the ESP) for a two-month performance evaluation. A mercury removal rate of 50-70% was targeted for the long-term test. During this continuous-injection test, mercury removal performance and variability were evaluated as the plant operated under normal conditions. Additional evaluations were made to determine any

  20. Refining the art of coal upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Nickell, R.

    1993-10-01

    SGI International's Liquids from coal (LFC) Process converts low-rank coals into condensable hydrocarbons, or coal-derived liquid (CDL), a solid product, called process-derived fuels (PDF), non-condensable gases and pyrolysis water. This paper describes the process, which consists of three basic steps (drying, pyrolysis, and finishing or conditioning), the process control system and the characteristics of and markets for the two main coproducts, CDF and PDF. It also describes, the technical feasibility study that SGT International carries out when it wants to determine the applicability of the LFC Process to a particular sub-bituminous or lignite coal. The paper discusses the economics of coal upgrading in general and of the LFC Process in particular. A 1000 short ton-per-day demonstration plant has been completed at the Buckskin Mine in the Powder River Basin, Wyoming. The cost of construction (which was completed in late Spring 1992) and the first two years of operation are being partly funded through the USDOE's Clean Coal Technology Program. 9 refs., 11 figs., 6 tabs.

  1. Effect of temperature and stress on molecular structure and carbon monoxide generation of lignite from Kailuan mining area

    Institute of Scientific and Technical Information of China (English)

    Xiao Cangyan; Wei Chongtao; Guo Li Wen; Shen Jian

    2016-01-01

    In order to analyze the origin of carbon monoxide (CO) in coal seams, stress–strain experiments under temperature of 50, 150 and 250 °C were conducted using lignite from Kailuan mining area. Fourier trans-form infrared spectroscopy and elemental analysis were carried out before and after deformation of the samples. The results indicated that CO generated at 150 and 250 °C;the gas component was mostly oxy-gen (O2), with small amount of carbon dioxide (CO2), methane (CH4) and hydrogen (H2). At 50 °C, O2 and a little CO2 were observed and no CO was found. The carbon content of the coal samples increased slightly after deformation, and the oxygen content, H/C ratio, and O/C ratio decreased. The molecular structure of coal displayed different evolution characteristics at various temperatures. At 50 and 150 °C, the falling off of side chains, broken of ether bond and directional realignment of the aliphatic chains resulting in the formation of long chains were the main performance of coal molecular structure evolution. While at 250 °C, the side chains fell off and short chains formed. Furthermore, at both 150 and 250 °C, condensed degree of aromatic ring increased. Under the action of temperature and pressure, CO forms in two ways. The first is that ether bond breaks, oxygen and carbon atoms combine together and forms CO, or O2 form-ing in the broken of ether–oxygen bond leads to the oxidation of free radicals and resulting in the forma-tion of CO. And the second is that CO derives from falling off of C=O group.

  2. Sumpor u ugljenu (Sulphur in Coal

    Directory of Open Access Journals (Sweden)

    Rađenović, A.

    2004-12-01

    Full Text Available The presence of sulphur in coal possesses important environmetal problems in its usage. The sulphur dioxide (S02 emissions produced during coal combustion account for a significant proportion of the total global output of anthropogenic SO2. The extent of sulphur separation depends on several variables such as the form of sulphur in coal, intimacy of contact between minerals and the products of devolatilization. The total sulphur in coal varies in the range of 0.2 - 11 wt %, although in most cases it is beetwen 1 and 3 wt %. Sulphur occurs in a variety of both inorganic and organic forms. Inorganic sulphur is found mainly as iron pyrite, marcasite, pyrrhotite, sphalerite, galena, chalcopirite and as sulphates (rarely exceeds w = 0,1 %. Organic sulphur is found in aromatic rings and aliphatic functionalities usually as mercaptans, aliphatic and aryl sulfides, disulfides and thiophenes. Organic and pyritic sulphur quantities depend on coal rank. Higher rank coals tend to have a high proportion of labile sulphur. All the organic sulphur is bivalent and it is spread throughout the organic coal matrix. Sulphur occurs in all the macerals and most minerals. Vitrinite contains the major part of organic sulphur and metals. Elemental sulphur is produced during coal weathering. The depolymerization methods as pyrolysis and hydrogenation are very drastic methods wich change the structure of the coal and the sulphur groups. In the case of pyrolysis, high levels of desulphurization, in chars and additional production of liquid hydrocarbon can be achieved. Thiophenes and sulphides were the major sulphur components of tars from coal pyrolysis. Hyrdogen sulphide and the lower mercaptans and sulphides were found in the volatile matters. Hydrogen sulphide and thiophenes are practically the only sulphur products of coal hydrogenation. H2S is produced in char hydrodesulphurization. A number of options are available for reducing sulphur emissions including the

  3. Determining the area of influence of depression cone in the vicinity of lignite mine by means of triangle method and LANDSAT TM/ETM+ satellite images.

    Science.gov (United States)

    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

  4. Controlling the excess heat from oxy-combustion of coal by blending with biomass

    Energy Technology Data Exchange (ETDEWEB)

    Haykiri-Acma, H.; Turan, A.Z.; Yaman, S.; Kucukbayrak, S. [Istanbul Technical University, Chemical and Metallurgical Engineering Faculty, Chemical Engineering Department, 34469, Maslak, Istanbul (Turkey)

    2010-11-15

    Two different biomass species such as sunflower seed shell and hazelnut shell were blended with Soma-Denis lignite to determine the effects of co-combustion on the thermal reactivity and the burnout of the lignite sample. For this purpose, Thermogravimetric Analysis and Differential Scanning Calorimetry techniques were applied from ambient to 900 C with a heating rate of 40 C/min under dry air and pure oxygen conditions. It was found that the thermal reactivities of the biomass materials and the lignite are highly different from each other under each oxidizing medium. On the other hand, the presence of biomass in the burning medium led to important influences not only on the burnout levels but also on the heat flows. The heat flow from the burning of lignite increased fivefold when the oxidizing medium was altered from dry air to pure oxygen. But, in case of co-combustion under oxygen, the excess heat arising from combustion of lignite could be reduced and this may be helpful to control the temperature of the combustion chamber. Based on this, co-combustion of coal/biomass blends under oxygen may be suggested as an alternative method to the ''Carbon Dioxide Recycle Method'' encountered in the oxyfuel combustion systems. (author)

  5. Adsorption of SO2 on bituminous coal char and activated carbon fiber prepared from phenol formaldehyde

    Science.gov (United States)

    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

  6. Distributions of rare-earth elements in two Chinese coals and their burnt products

    Institute of Scientific and Technical Information of China (English)

    YAO Duo-xi; ZHI Xia-chen

    2005-01-01

    The concentrations of two fresh Chinese coals (lignitie and fatty coal ) from different geological origin and the corresponding fly and bottom ashes were determined using inductively coupled plasma mass spectrometry(ICP-MS). The ranges and means of concentrations of these elemennts were given. Based on the combustion simulating experiment in the one-dismensional boiler, the contents of REE (rare-earth element) of 18samples in lignite, fatty coal and their fly and bottom ashes in different combustion condition were determined, and geochemical feature of REE were analyzed.

  7. Investigation of the combustion characteristics of Zonguldak bituminous coal using DTA and DTG

    Energy Technology Data Exchange (ETDEWEB)

    Haykiri-Acma, H.; Yaman, S.; Kucukbayrak, S.; Okutan, H. [Istanbul Technical University, Istanbul (Turkey). Dept. of Chemical Engineering

    2006-06-21

    Combustion characteristics of coking, semicoking, and noncoking Turkish bituminous coal samples from Zonguldak basin were investigated applying differential thermal analysis (DTA) and differential thermogravimetry (DTG) techniques. Results were compared with that of the coke from Zonguldak bituminous coal, a Turkish lignite sample from Soma, and a Siberian bituminous coal sample. The thermal data from both techniques showed some differences depending on the proximate analyses of the samples. Noncombustible components of the volatile matter led to important changes in thermal behavior. The data front both methods were, evaluated jointly, and some thermal properties were interpreted considering these methods in a complementary combination.

  8. Ash transformation during co-firing coal and straw

    DEFF Research Database (Denmark)

    Zheng, Yuanjing; Jensen, Peter Arendt; Jensen, Anker Degn;

    2007-01-01

    Co-firing straw with coal in pulverized fuel boilers can cause problems related to fly ash utilization, deposit formation, corrosion and SCR catalyst deactivation due to the high contents of Cl and K in the ash. To investigate the interaction between coal and straw ash and the effect of coal...... quality on fly ash and deposit properties, straw was co-fired with three kinds of coal in an entrained flow reactor. The compositions of the produced ashes were compared to the available literature data to find suitable scaling parameters that can be used to predict the composition of ash from straw...... importantly, by reaction with Al and Si in the fly ash. About 70-80% K in the fly ash appears as alumina silicates while the remainder K is mainly present as sulphate. Lignite/straw co-firing produces fly ash with relatively high Cl content. This is probably because of the high content of calcium...

  9. Influence of coal properties on mercury uptake from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Lakatos, J.; Brown, S.D.; Snape, C.E. [Miskolc University, Miskolc-Egyetemvaros (Hungary). Research Inst. of Applied Chemistry

    1999-10-01

    The uptake of mercury (II) from aqueous solution by a range of coals has been studied and the results have been compared to those for a number of other sorbents, including commercial active carbons and cation-exchange resins. At pH 5 in a buffer medium, the capacities for mercury removal of the low-rank coals and the oxidized bituminous coals investigated are comparable to those of the other sorbents tested. For the lignites investigated, a high content of organic sulfur does not markedly affect the capacity for mercury uptake in relatively neutral and low chloride media, owing to redox reactions being the most likely mechanism involved. However, in highly acidic solutions, the capacities for mercury uptake are considerably greater for the high-sulfur coals investigated than for their low-sulfur counterparts due to chelation being the major sorption process involved. 36 refs., 4 figs., 7 tabs.

  10. JV Task 117 - Impact of Lignite Properties on Powerspan's NOx Oxidation System

    Energy Technology Data Exchange (ETDEWEB)

    Scott Tolbert; Steven Benson

    2008-02-29

    Powerspan's multipollutant control process called electrocatalytic oxidation (ECO) technology is designed to simultaneously remove SO{sub 2}, NO{sub x}, PM{sub 2.5}, acid gases (such as hydrogen fluoride [HF], hydrochloric acid [HCl], and sulfur trioxide [SO{sub 3}]), Hg, and other metals from the flue gas of coal-fired power plants. The core of this technology is a dielectric barrier discharge reactor composed of cylindrical quartz electrodes residing in metal tubes. Electrical discharge through the flue gas, passing between the electrode and the tube, produces reactive O and OH radicals. The O and OH radicals react with flue gas components to oxidize NO to NO{sub 2} and HNO{sub 3} and a small portion of the SO{sub 2} to SO{sub 3} and H{sub 2}SO{sub 4}. The oxidized compounds are subsequently removed in a downstream scrubber and wet electrostatic precipitator. A challenging characteristic of selected North Dakota lignites is their high sodium content. During high-sodium lignite combustion and gas cooling, the sodium vaporizes and condenses to produce sodium- and sulfur-rich aerosols. Based on past work, it was hypothesized that the sodium aerosols would deposit on and react with the silica electrodes and react with the silica electrodes, resulting in the formation of sodium silicate. The deposit and reacted surface layer would then electrically alter the electrode, thus impacting its dielectric properties and NO{sub x} conversion capability. The purpose of this project was to determine the impact of lignite-derived flue gas containing sodium aerosols on Powerspan's dielectric barrier discharge (DBD) reactor with specific focus on the interaction with the quartz electrodes. Partners in the project were Minnkota Power Cooperative; Basin Electric Power Cooperative; Montana Dakota Utilities Co.; Minnesota Power; the North Dakota Industrial Commission, the Lignite Energy Council, and the Lignite Research Council; the Energy & Environmental Research Center

  11. Measurement and modeling of advanced coal conversion processes, Volume III

    Energy Technology Data Exchange (ETDEWEB)

    Ghani, M.U.; Hobbs, M.L.; Hamblen, D.G. [and others

    1993-08-01

    A generalized one-dimensional, heterogeneous, steady-state, fixed-bed model for coal gasification and combustion is presented. The model, FBED-1, is a design and analysis tool that can be used to simulate a variety of gasification, devolatilization, and combustion processes. The model considers separate gas and solid temperatures, axially variable solid and gas flow rates, variable bed void fraction, coal drying, devolatilization based on chemical functional group composition, depolymerization, vaporization and crosslinking, oxidation, and gasification of char, and partial equilibrium in the gas phase.

  12. Improving the effectiveness of wells for lignite mine dewatering

    Energy Technology Data Exchange (ETDEWEB)

    Rude, T.R.; Banning, A. [Aachen Univ. (Germany). Inst. of Hydrogeology; Klauder, W.; Roger, S. [Aachen Univ. (Germany). Inst. of Hydraulic Engineering and Water Resources Management; Vinzelberg, G. [RWE Power AG, Bergheim (Germany). Dept. of Water Resources Management

    2010-07-01

    Mine dewatering is an important factor in determining the economic feasibility of lignite open cast mining projects. Ochre formation is accelerated in open pit dewatering, as the wells have long filter lengths that allow for high oxygen flux into well screens, gravel packs, and the surrounding aquifer. Ochre formation can reduce the productivity of wells by an estimated 20 percent. This experimental study investigated the formation of ochre in different environments using well screens from the Rhenish lignite mining district in Germany. The influence of oxygen, iron (Fe{sup 2+}), pH, flow velocity, water composition, and microorganisms were considered. Samples from the mine were passed through an apparatus that supplied Fe{sup 2+} and filtered the formed Fe{sup 3+} oxide colloids. The oxygen- and iron-free water was then conditioned and treated with ultraviolet (UV) radiation. Results of the study showed that Fe{sup 3+} hydroxides quickly formed in the screen due to high Fe{sup 2+} concentrations. Results indicated that pH must be kept high in the deoxygenation unit in order to facilitate rapid oxygen consumption. The experimental study will be used to investigate abiotic conditions created by variations in flow velocity, Fe{sup 2+} concentrations, sulfate content and alkalinity. 7 refs., 3 figs.

  13. Exergy Analysis of Operating Lignite Fired Thermal Power Plant

    Directory of Open Access Journals (Sweden)

    K. Murugesan

    2009-01-01

    Full Text Available The energy assessment must be made through the energy quantity as well as the quality. But the usual energy analysisevaluates the energy generally on its quantity only. However, the exergy analysis assesses the energy on quantity as well asthe quality. The aim of the exergy analysis is to identify the magnitudes and the locations of real energy losses, in order toimprove the existing systems, processes or components. The present paper deals with an exergy analysis performed on anoperating 50MWe unit of lignite fired steam power plant at Thermal Power Station-I, Neyveli Lignite Corporation Limited,Neyveli, Tamil Nadu, India. The exergy losses occurred in the various subsystems of the plant and their components havebeen calculated using the mass, energy and exergy balance equations. The distribution of the exergy losses in several plantcomponents during the real time plant running conditions has been assessed to locate the process irreversibility. The Firstlaw efficiency (energy efficiency and the Second law efficiency (exergy efficiency of the plant have also been calculated.The comparison between the energy losses and the exergy losses of the individual components of the plant shows that themaximum energy losses of 39% occur in the condenser, whereas the maximum exergy losses of 42.73% occur in the combustor.The real losses of energy which has a scope for the improvement are given as maximum exergy losses that occurredin the combustor.

  14. Mercury in coal. A review. Part 1

    Energy Technology Data Exchange (ETDEWEB)

    Yudovich, Ya. E.; Ketris, M.P. [Institute of Geology, Komi Scientific Center, Ural Division of the Russian Academy of Sciences, Morozova St., 100, ap. 49, 167023 Syktyvkar (Russian Federation)

    2005-05-11

    This is the first of two papers that review approximately 200 publications on mercury (Hg) in coal; topics reviewed in this paper include: (a) analytical and historical introduction; (b) some peculiarities of Hg environmental geochemistry; (c) estimation of the Hg coal Clarke value; (d) occurrence of high-Hg coals; (e) mode of Hg occurrence in coal; (f) factors influencing the distribution of Hg in coal; and (g) origins of Hg in coal. Aspects of the environmental impact of Hg due to coal combustion and coking are noted throughout the review, and are more fully examined in second and final paper of this review. The Clarke value for Hg in coal (world-wide average Hg content) is 0.10 (+/-0.01) ppm Hg, regardless of coal rank. However, if the Hg content is expressed on an ash basis, bituminous rank coals average 0.87 (+/-0.08 ppm) Hg, and lower rank coals average 0.62 (+/-0.06) ppm. In general, Hg is a very 'coalphile' element; that is, it has a strong affinity for organic and inorganic coal matter, but is obligatory authigenic. There are some coals that are enriched in Hg by 1 to 2 orders of magnitude above the Clarke value. Such coals are located in the Donbas (Ukraine), Appalachian basin and Texas (USA), Russian Far East, and Southern China. Mercury in these coals is usually accompanied by other chalcophile trace elements. In low-sulfur coals, which are generally poor in Hg, only two Hg sites dominate: Hg{sub org} and Hg{sub sulfide} (commonly pyritic mercury, Hg{sub pyr}). High-sulfur coals usually contain higher amounts of Hg, which is typically in the Hg{sub pyr} form. In the unique Hg-enriched Donbas coals, both HgS and metallic mercury (Hg{sup o}) also occur. Because of the extremely strong affinity of Hg{sup 2+} for humic matter, it is theoretically possible for syngenetic (or early epigenetic) Hg to accumulate in peats and lignites. Indeed, the amount of Hg in some tropic and moderate zone peats is greater than or equal to the Hg content of typical

  15. The release of iron during coal combustion. Milestone report

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, L.L. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility

    1995-06-01

    Iron plays an important role in the formation of both fly ash and deposits in many pulverized-coal-fired boilers. Several authors indicate that iron content is a significant indicator of the slagging propensity of a majority of US bituminous coals, in particular eastern bituminous coals. The pyritic iron content of these coals is shown to be a particularly relevant consideration. A series of investigations of iron release during combustion is reported for a suite of coals ranging in rank from lignite to low-volatile bituminous coal under combustion conditions ranging from oxidizing to inert. Experimental measurements are described in which, under selected conditions, major fractions of the iron in the coal are released within a 25 ms period immediately following coal devolatilization. Mechanistic interpretation of the data suggest that the iron is released as a consequence of oxygen attack on porous pyrrhotite particles. Experimental testing of the proposed mechanism reveals that the release is dependent on the presence of both pyrite in the raw coal and oxygen in the gas phase, that slow preoxidation (weathering) of the pyrite significantly inhibits the iron release, and that iron loss increases as oxygen penetration of the particle increases. Each observation is consistent with the postulated mechanism.

  16. Fungal degradation of coal as a pretreatment for methane production

    Science.gov (United States)

    Haider, Rizwan; Ghauri, Muhammad A.; SanFilipo, John R.; Jones, Elizabeth J.; Orem, William H.; Tatu, Calin A.; Akhtar, Kalsoom; Akhtar, Nasrin

    2013-01-01

    Coal conversion technologies can help in taking advantage of huge low rank coal reserves by converting those into alternative fuels like methane. In this regard, fungal degradation of coal can serve as a pretreatment step in order to make coal a suitable substrate for biological beneficiation. A fungal isolate MW1, identified as Penicillium chrysogenum on the basis of fungal ITS sequences, was isolated from a core sample of coal, taken from a well drilled by the US. Geological Survey in Montana, USA. The low rank coal samples, from major coal fields of Pakistan, were treated with MW1 for 7 days in the presence of 0.1% ammonium sulfate as nitrogen source and 0.1% glucose as a supplemental carbon source. Liquid extracts were analyzed through Excitation–Emission Matrix Spectroscopy (EEMS) to obtain qualitative estimates of solubilized coal; these analyses indicated the release of complex organic functionalities. In addition, GC–MS analysis of these extracts confirmed the presence of single ring aromatics, polyaromatic hydrocarbons (PAHs), aromatic nitrogen compounds and aliphatics. Subsequently, the released organics were subjected to a bioassay for the generation of methane which conferred the potential application of fungal degradation as pretreatment. Additionally, fungal-mediated degradation was also prospected for extracting some other chemical entities like humic acids from brown coals with high huminite content especially from Thar, the largest lignite reserve of Pakistan.

  17. Eocene lignites from Cambay basin, Western India: An excellent source of hydrocarbon

    Directory of Open Access Journals (Sweden)

    P.K. Singh

    2016-09-01

    Full Text Available In the present paper lignites from the Cambay basin have been studied for their hydrocarbon potential. The samples were collected from three lignite fields–Vastan, Rajpardi and Tadkeshwar, and were investigated by petrography, chemical analyses and Rock-Eval pyrolysis. The results are well comparable with the empirically derived values. The study reveals that these ‘low rank C’ lignites are exceedingly rich in reactive macerals (huminite + liptinite while inertinite occurs in low concentration. These high volatile lignites generally have low ash yield except in few sections. The Rock-Eval data indicates the dominance of kerogen type-III with a little bit of type-II. The study reveals that the lignites of Vastan (lower and upper seams and Tadkeshwar upper seam are more gas-prone while Rajpardi and Tadkeshwar lower seams are oil-prone. Further, the fixed hydrocarbons are several times higher than the free hydrocarbons. The relation between TOC and fixed hydrocarbon indicates that these lignites are excellent source rock for hydrocarbon which could be obtained mainly through thermal cracking. The empirically derived values reveal a high conversion (94–96% and high oil yield (64–66% for these lignites.

  18. Eocene lignites from Cambay basin, Western India:An excellent source of hydrocarbon

    Institute of Scientific and Technical Information of China (English)

    P.K. Singh; V.K. Singh; P.K. Rajak; M.P. Singh; A.S. Naik; S.V. Raju; D. Mohanty

    2016-01-01

    In the present paper lignites from the Cambay basin have been studied for their hydrocarbon potential. The samples were collected from three lignite fieldseVastan, Rajpardi and Tadkeshwar, and were investigated by petrography, chemical analyses and Rock-Eval pyrolysis. The results are well comparable with the empirically derived values. The study reveals that these‘low rank C’ lignites are exceedingly rich in reactive macerals (huminite þ liptinite) while inertinite occurs in low concentration. These high volatile lignites generally have low ash yield except in few sections. The Rock-Eval data indicates the dominance of kerogen type-III with a little bit of type-II. The study reveals that the lignites of Vastan (lower and upper seams) and Tadkeshwar upper seam are more gas-prone while Rajpardi and Tad-keshwar lower seams are oil-prone. Further, the fixed hydrocarbons are several times higher than the free hydrocarbons. The relation between TOC and fixed hydrocarbon indicates that these lignites are excellent source rock for hydrocarbon which could be obtained mainly through thermal cracking. The empirically derived values reveal a high conversion (94e96%) and high oil yield (64e66%) for these lignites.

  19. Analysis of organic sulfur and nitrogen in coal via tandem degradation methods. Technical report, 1 December 1991--29 February 1992

    Energy Technology Data Exchange (ETDEWEB)

    Kruge, M.A.; Palmer, S.R.; Baudet, N.

    1992-08-01

    With the recent increase in concern for environmental issues and the implication of sulfur and nitrogen in coal combustion products as prime causes of acid rain, it has become clear that there is an urgent need for alternative methods for determining the nature of organic sulfur and nitrogen compounds in coal. The present study couples mild oxidative and reductive procedures to enhance the depolymerization of coal and its constituent macerals and the quantities of products amenable to analysis. The study also seeks to apply the degradative techniques to coal asphaltenes, since they are believed to be polymeric structures similar to the whole coal, but smaller and more readily analyzed.

  20. Effect of enzymatic depolymerization on physicochemical and rheological properties of guar gum.

    Science.gov (United States)

    Mudgil, Deepak; Barak, Sheweta; Khatkar, B S

    2012-09-01

    Depolymerization of guar gum using enzymatic hydrolysis was performed to obtain depolymerized guar gum having functional application as soluble dietary fiber. Enzymatic hydrolysis of guar gum significantly affected the physicochemical and rheological characteristics of guar gum. The depolymerized guar gum showed a significant increase in crystallinity index from 3.86% to 13.2% and flow behavior index from 0.31 to 1.7 as compared to native guar gum. Remarkable decrease in intrinsic viscosity and consistency index was also observed from 9 to 0.28 and 4.04 to 0.07, respectively. Results revealed that enzymatic hydrolysis of guar gum resulted in a polysaccharide with low degree of polymerization, viscosity and consistency which could make it useful for incorporation in food products as dietary fiber without affecting the rheology, consistency and texture of the products.

  1. The contribution of glutenin macropolymer depolymerization to the deterioration of frozen steamed bread dough quality.

    Science.gov (United States)

    Wang, Pei; Lee, Tung-Ching; Xu, Xueming; Jin, Zhengyu

    2016-11-15

    Depolymerization of glutenin macropolymers (GMP) widely exists in the frozen dough with little effort in elucidating its effects on steamed bread quality. To clarify this, GMP was fractionated from wheat flour and reconstituted to yeast and chemical leavened dough (YLD/CLD). Results showed that with supplementary GMP fraction, depolymerization degree was alleviated in frozen dough. The bread quality loss from freezing was partially counteracted along with better preserved GMP content. Both of dough elasticity and gas retention capability were enhanced in GMP-enriched frozen dough. Gassing power in frozen YLD decreased while remained constant in CLD. Addition of GMP did not affect the gassing power, which allowed interpreting the improved bread qualities from the enhanced dough elasticity and gas retention capability. Based on the improved facts of frozen steamed bread dough quality with additional GMP fractions, this study revealed the pivotal role of GMP depolymerization on the frozen steamed bread dough quality. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. 移动床中褐煤直接热解特性%In-situ pyrolysis behavior of lignite in a moving bed reactor

    Institute of Scientific and Technical Information of China (English)

    高豪杰; 朱跃钊; 杜杨; 吴昊; 陈海军; 范红途

    2016-01-01

    coal particle, and it can strengthen the semi-coke gasification reaction and the volatiles reforming reaction. Furthermore, the rise of particle size increases the mass transfer resistance of the pore in lignite particles, leading to the strengthened secondary reaction. The optimum lignite particle size for its in-situ pyrolysis is 1.6−3.2 mm.

  3. Sixteenth Quarterly Report Regulation of Coal Polymer Degradation by Fungi

    Energy Technology Data Exchange (ETDEWEB)

    John A. Bumpus

    1998-07-31

    Three phenomena which concern coal solubilization and depolymerization were studied during this reporting period. Previous investigations have shown that lignin peroxidases mediate the oxidation of soluble coal macromolecule. Because it appears to be a substrate, soluble coal macromolecule is also an inhibitor of veratryl alcohol oxidation, a reaction that is mediated by these enzymes. The mechanism of inhibition is complex in that oxidation (as assayed by decolorization) of soluble coal macromolecule requires the presence of veratryl alcohol and veratryl alcohol oxidation occurs only after a substantial lag period during which the soluble coal macromolecule is oxidized. In a previous quarterly report we proposed a reaction mechanism by which this may occur. During the present reporting period we showed that our proposed reaction mechanism is consistent with classical enzyme kinetic theory describing enzyme activity in the presence of a potent inhibitor (i.e., an inhibitor with a very low KI ). The oxidative decolorization and depolymerization of soluble coal macromolecule was also studied. Because wood rotting fungi produce hydrogen peroxide via a variety of reactions, we studied the effect of hydrogen peroxide on soluble coal macromolecule decolorization and depolymerization. Results showed that substantial decolorization occurred only at hydrogen peroxide concentrations that are clearly non-physiological (i.e., 50 mM or greater). It was noted, however, that when grown on solid lignocellulosic substrates, wood rotting fungi, overtime, cumulatively could produce amounts of hydrogen peroxide that might cause significant oxidative degradation of soluble coal macromolecule. Thirdly, we have shown that during oxalate mediated solubilization of low rank coal, a pH increase is observed. During this reporting period we have shown that the pH of solutions containing only sodium oxalate also undergo an increase in pH, but to a lesser extent than that observed in mixtures

  4. Flash hydropyrolysis of coal. Quarterly report No. 9, April 1-June 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-10-01

    Both the North Dakota lignite and New Mexico sub-bituminous coal have been hydrogasified in the Flash Hydropyrolysis unit with yields ranging up to about 85 to 90% conversion of the available carbon at 2500 psi and 875 to 900/sup 0/C. The lignite appears to be less reactive at lower pressure than the sub-bituminous coal, producing an average of 40% gaseous yield at 1000 psi and 900/sup 0/C while the sub-bituminous produced over 50%. The reactivity of both coals is dependent on the hydrogen partial pressure but does not appear to be affected by H/sub 2//coal feed ratio. When the H/sub 2//coal ratio was reduced to 0.05 and sub-bituminous coal was run at 2500 psi and 875/sup 0/C, a high methane concentration of 57% was achieved. However, the yield or conversion of carbon to gas was limited to 30% which may be attributed to the reduction in hydrogen partial pressure during the run. Further work is being planned to obtain additional data at the lower pressure and H/sub 2//coal feed ratios. Illinois No. 6 coal, a caking bituminous, has been successfully run in the experimental equipment both treated with calcium and untreated. A reaction model, previously developed, has been modified and is being fitted to all the lignite data to produce one consistent set of pre-exponential factors and activation energies for the reaction rate equations. The experimental equipment is being modified to allow varying feed composition and especially introduction of steam into the feed gas.

  5. Arsenic and copper stabilisation in a contaminated soil by coal fly ash and green waste compost.

    Science.gov (United States)

    Tsang, Daniel C W; Yip, Alex C K; Olds, William E; Weber, Paul A

    2014-09-01

    In situ metal stabilisation by amendments has been demonstrated as an appealing low-cost remediation strategy for contaminated soil. This study investigated the short-term leaching behaviour and long-term stability of As and Cu in soil amended with coal fly ash and/or green waste compost. Locally abundant inorganic (limestone and bentonite) and carbonaceous (lignite) resources were also studied for comparison. Column leaching experiments revealed that coal fly ash outperformed limestone and bentonite amendments for As stabilisation. It also maintained the As stability under continuous leaching of acidic solution, which was potentially attributed to high-affinity adsorption, co-precipitation, and pozzolanic reaction of coal fly ash. However, Cu leaching in the column experiments could not be mitigated by any of these inorganic amendments, suggesting the need for co-addition of carbonaceous materials that provides strong chelation with oxygen-containing functional groups for Cu stabilisation. Green waste compost suppressed the Cu leaching more effectively than lignite due to the difference in chemical composition and dissolved organic matter. After 9-month soil incubation, coal fly ash was able to minimise the concentrations of As and Cu in the soil solution without the addition of carbonaceous materials. Nevertheless, leachability tests suggested that the provision of green waste compost and lignite augmented the simultaneous reduction of As and Cu leachability in a fairly aggressive leaching environment. These results highlight the importance of assessing stability and remobilisation of sequestered metals under varying environmental conditions for ensuring a plausible and enduring soil stabilisation.

  6. Cooperation, competition, and coalitions in enzyme-producing microbes: Social evolution and nutrient depolymerization rates

    Directory of Open Access Journals (Sweden)

    Henry Joseph Folse

    2012-09-01

    Full Text Available Extracellular enzymes represent a public good for microbial communities, as they break down complex molecules into simple molecules that microbes can take up. These communities are vulnerable to cheating by microbes that do not produce enzymes, but benefit from those produced by others. However, extracellular enzymes are ubiquitous and play an important role in the depolymerization of nutrients. We developed a multi-genotype, multi-nutrient model of a community of exoenzyme-producing microbes, in order to investigate the relationship between diversity, social interactions, and nutrient depolymerization. We focused on coalitions between complementary types of microbes and their implications for spatial pattern formation and nutrient depolymerization. The model included polymers containing carbon, nitrogen, or phosphorus, and eight genotypes of bacteria, which produced different subsets of the three enzymes responsible for hydrolyzing these polymers. We allowed social dynamics to emerge from a mechanistic model of enzyme production, action, and diffusion. We found that diversity was maximized at high rates of either diffusion or enzyme production (but not both. Conditions favoring cheating also favored the emergence of coalitions. We characterized the spatial patterns formed by different interactions, showing that same-type cooperation leads to aggregation, but between-type cooperation leads to an interwoven, filamentous pattern. Contrary to expectations based on niche complementarity, we found that nutrient depolymerization declined with increasing diversity due to a negative competitive effect of coalitions on generalist producers, leading to less overall enzyme production. This decline in depolymerization was stronger for non-limiting nutrients in the system. This study shows that social interactions among microbes foraging for complementary resources can influence microbial diversity, microbial spatial distributions, and rates of nutrient

  7. Cooperation, competition, and coalitions in enzyme-producing microbes: social evolution and nutrient depolymerization rates.

    Science.gov (United States)

    Folse, Henry J; Allison, Steven D

    2012-01-01

    Extracellular enzymes represent a public good for microbial communities, as they break down complex molecules into simple molecules that microbes can take up. These communities are vulnerable to cheating by microbes that do not produce enzymes, but benefit from those produced by others. However, extracellular enzymes are ubiquitous and play an important role in the depolymerization of nutrients. We developed a multi-genotype, multi-nutrient model of a community of exoenzyme-producing microbes, in order to investigate the relationship between diversity, social interactions, and nutrient depolymerization. We focused on coalitions between complementary types of microbes and their implications for spatial pattern formation and nutrient depolymerization. The model included polymers containing carbon, nitrogen, or phosphorus, and eight genotypes of bacteria, which produced different subsets of the three enzymes responsible for hydrolyzing these polymers. We allowed social dynamics to emerge from a mechanistic model of enzyme production, action, and diffusion. We found that diversity was maximized at high rates of either diffusion or enzyme production (but not both). Conditions favoring cheating also favored the emergence of coalitions. We characterized the spatial patterns formed by different interactions, showing that same-type cooperation leads to aggregation, but between-type cooperation leads to an interwoven, filamentous pattern. Contrary to expectations based on niche complementarity, we found that nutrient depolymerization declined with increasing diversity due to a negative competitive effect of coalitions on generalist producers, leading to less overall enzyme production. This decline in depolymerization was stronger for non-limiting nutrients in the system. This study shows that social interactions among microbes foraging for complementary resources can influence microbial diversity, microbial spatial distributions, and rates of nutrient depolymerization.

  8. Alternating Sulfone Copolymers Depolymerize in Response to Both Chemical and Mechanical Stimuli.

    Science.gov (United States)

    Kumar, Kaushlendra; Goodwin, Andrew P

    2015-09-15

    This work describes the depolymerization of poly(vinyl acetate-alt-sulfur dioxide) (PVAS) as initiated by chemical and mechanical stimuli. In recent years, macromolecules that are able to depolymerize in response to specific stimuli have been highly sought because of their ability to amplify signal for sensing and drug delivery. Examples include self-immolative polymers from alkoxyphenol derivatives and polyaldehydes. We show here that alternating copolymers of sulfur dioxide and vinyl acetate are able to undergo similar depolymerization into their monomer components in response to various chemical and mechanical stimuli. Certain vinyl monomers such as vinyl acetate are able to polymerize with sulfur dioxide in a perfectly alternating manner, and the resulting copolymer possesses a low ceiling temperature. We show that this polymer is able to break down into its monomer components when subjected to UV/acetone, various Reactive Oxygen Species (ROS), and ultrasonication. In the case of UV, the acetone reacted via a Norrish reaction to produce free radicals that caused clean monomer production. For ROS, the polymer showed reactivity to both oxidizing and radical-containing ROS. Through kinetic studies, these polymers were shown to proceed via a two-part, first-order kinetic model with a fast initiation phase and a slow depolymerization phase. Finally, the polymers were subjected to probe ultrasonication, and depolymerization occurred as well. Most tellingly, the polymer again showed a fast initiation step and continued to depolymerize even after ultrasonication stopped. This class of polymers shows potential for drug delivery in response to both endogenous chemical and externally-applied mechanical cues.

  9. Large scale solubilization of coal and bioconversion to utilizable energy. Quarterly report, October 1--December 31, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, N.C.

    1996-12-22

    In order to develop a system for a large scale coal solubilization and its bioconversion to utilizable fuel, the author plans to clone the genes encoding Neurospora protein that facilitate depolymerization of coal. He also plans to use desulfurizing bacteria to remove the sulfur in situ and use other microorganisms to convert biosolubilized coal into utilizable energy following an approach utilizing several microorganisms. In addition the product of coal solubilized by fungus will be characterized to determine their chemical nature and the mechanism of reaction catalyzed by fungal product during in vivo and in vitro solubilization by the fungus or purified fungal protein.

  10. Large scale solubilization of coal and bioconversion to utilizable energy. Fifth quarterly technical report, January 1, 1995--March 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, N.C.

    1995-12-01

    In order to develop a system for a large scale coal solubilization and its bioconversion to utilizable fuel, we plan to clone the genes encoding Neurospora protein that facilitate depolymerization of coal. We also plan to use desulfurizing bacteria to remove the sulfur in situ and use other microorganisms to convert biosolubilized coal into utilizable energy following an approach utilizing several microorganisms. In addition the product of coal solubilized by fungus will be characterized to determine their chemical nature and the mechanism of reaction catalyzed by fungal product during in vivo and in vitro solubilization by the fungus or purified fungal protein.

  11. Sulfomethylated lignite salt as a sacrifical agent in oil recovery processes

    Energy Technology Data Exchange (ETDEWEB)

    Kudchadker, M.V.; Weiss, W.J.

    1978-02-07

    A process is described for recovering petroleum from oil reservoirs by secondary recovery methods. The process involves injecting via an injection well into the reservoir an aqueous solution of sulfomethylated lignite salt as a sacrificial agent to inhibit the deposition of surfactant and polymer on the reservoir matrix. The process is conducted by first injecting the lignite salt into the formation through the injection well and following it with either a polymer or a surfactant solution, which also may contain the lignite salt. The polymer or surfactant would then be followed by a drive fluid, such as water, to push the chemicals and oil to the production well. (18 claims)

  12. Innovative approach to ash radioactivitiy and health impacts of lignite power plants

    Energy Technology Data Exchange (ETDEWEB)

    Bosevski, T.; Pop-Jordanova, N. [Macedonian Academy of Sciences and Arts, Skopje (Macedonia)

    1998-12-31

    In Macedonia nearly 90% of the present electricity production utilizes domestic low-calorie lignite, and this is likely to continue for the next few decades. Local and global environmental impacts of fossil fuel utilization are considered. Some innovative extensions to standard methodologies of environmental risk assessment and management are considered. They involve ash radioactivity and psychosomatic health impacts from lignite power plants. Two extensions are proposed: one comprising complete radioactive chains when determining committed effective dose from lignite ash; the other by including the psychosomatic diseases, such as peptic ulcer and arterial hypertension, due to chronic stress induced by power plants during normal operation. 7 refs., 2 figs., 3 tabs.

  13. Effects of pyrolysis on the proximate and ultimate analysis of lignite

    Energy Technology Data Exchange (ETDEWEB)

    Kucukbayrak, S.; Kadioglu, E. (Istanbul Technical University, Istanbul (Turkey). Dept. of Chemical Engineering)

    1989-12-10

    The effect of pyrolysis over the temperature range 300-1000{degree}C on the proximate and ultimate analysis of lignite has been studied and the experimental results are presented here. Seven lignite samples from different reserves in Turkey with particle diameters of 0.1-0.2 mm were subjected to pyrolysis. The volatile matter contents of the lignite samples decreased by about 90%. The fraction of the calorific value remaining in the coke produced varies from 51 to 75%. The oxygen and hydrogen content decrease the most during pyrolysis. 5 refs., 6 tabs., 1 fig.

  14. Rank evaluation of the Neyveli lignite deposit on the basis of reflectance parameter

    Energy Technology Data Exchange (ETDEWEB)

    Singh, A.; Singh, B.D. (Birbal Sahni Institute of Paleobotany, Lucknow (India))

    1994-10-01

    The Neyveli field is well known for Tertiary lignite deposits in India. The reflectance of organic constituents (huminite macerals) has been measured to find out organic maturation level (rank) of the main lignite seam lying either at same time level or at different time levels in space. The deposits are of sub-bituminous C stage (ASTM) with the mean reflectance (R[sub o,max.] in oil) range from 0.34 to 0.42% (average 0.39%). Evidence from rank study indicates that the quality of lignite deteriorates towards southern part of the field

  15. Kinetics and Thermodynamics of Ultrasound-Assisted Depolymerization of κ-Carrageenan

    Directory of Open Access Journals (Sweden)

    Ratnawati Ratnawati

    2016-03-01

    Full Text Available The ultrasound-assisted depolymerization of κ-carrageenan has been studied at various temperatures and times. The κ-carrageenan with initial molecular weight of 545 kDa was dispersed in water to form a 5 g/L solution, which was then depolymerized in an ultrasound device at various temperatures and times. The viscosity of the solution was measured using Brookfield viscometer, which was then used to find the number-average molecular weight by Mark-Houwink equation. To obtain the kinetics of κ-carrageenan depolymerization, the number-average molecular weight data was treated using midpoint-chain scission kinetics model. The pre-exponential factor and activation energies for the reaction are 2.683×10-7 mol g-1 min-1 and 6.43 kJ mol-1, respectively. The limiting molecular weight varies from 160 kDa to 240 kDa, and it is linearly correlated to temperature. The results are compared to the result of thermal depolymerization by calculating the half life. It is revealed that ultrasound assisted depolymerization of κ-carrageenan is faster than thermal depolymerization at temperatures below 72.2°C. Compared to thermal depolymerization, the ultrasound-assisted process has lower values of Ea, ΔG‡, ΔH‡, and ΔS‡, which can be attributed to the ultrasonically induced breakage of non-covalent bonds in κ-carrageenan molecules. Copyright © 2016 BCREC GROUP. All rights reserved Received: 10th November 2015; Revised: 18th January 2016; Accepted: 19th January 2016 How to Cite: Ratnawati, R., Prasetyaningrum, A., Wardhani, D.H. (2016. Kinetics and Thermodynamics of Ultrasound-Assisted Depolymerization of κ-Carrageenan. Bulletin of Chemical Reaction Engineering & Catalysis, 11(1: 48-58. (doi:10.9767/bcrec.11.1.415.48-58 Permalink/DOI: http://dx.doi.org/10.9767/bcrec.11.1.415.48-58

  16. A case study of PFBC for low rank coals

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, S.A. [ABB Carbon AB, Finspong (Sweden)

    1995-12-01

    Pressurized Fluidized Combined-Cycle (PFBC) technology allows the efficient and environmentally friendly utilization of solid fuels for power and combined heat and power generation. With current PFBC technology, thermal efficiencies near 46%, on an LHV basis and with low condenser pressures, can be reached in condensing power plants. Further efficiency improvements to 50% or more are possible. PFBC plants are characterized by high thermal efficiency, compactness, and extremely good environmental performance. The PFBC plants which are now in operation in Sweden, the U.S. and Japan burn medium-ash, bituminous coal with sulfur contents ranging from 0.7 to 4%. A sub- bituminous {open_quotes}black lignite{close_quotes} with high levels of sulfur, ash and humidity, is used as fuel in a demonstration PFBC plant in Spain. Project discussions are underway, among others in Central and Eastern Europe, for the construction of PFBC plants which will burn lignite, oil-shale and also mixtures of coal and biomass with high efficiency and extremely low emissions. This paper will provide information about the performance data for PFBC plants when operating on a range of low grade coals and other solid fuels, and will summarize other advantages of this leading new clean coal technology.

  17. Influence of high-energy impact on the physical and technical characteristics of coal fuels

    Science.gov (United States)

    Mal'tsev, L. I.; Belogurova, T. P.; Kravchenko, I. V.

    2017-08-01

    Currently, in the world's large-scale coal-fired power industry, the combustion of pulverized coal is the most widely spread technology of combusting the coals. In recent years, the micropulverization technology for preparation and combustion of the coal has been developed in this field. As applied to the small-scale power industry, the method of combusting the coal in the form of a coal-water slurry has been explored for years. Fine coal powders are produced and used in the pulverized-coal gasification. Therefore, the coal preparation methods that involve high-dispersion disintegration of coals attract the greatest interest. The article deals with the problems of high-energy impact on the coal during the preparation of pulverized-coal fuels and coal-water slurries, in particular, during the milling of the coal in ball drum mills and the subsequent regrinding in disintegrators or the cavitation treatment of the coal-water slurries. The investigations were conducted using samples of anthracite and lignite from Belovskii open-pit mine (Kuznetsk Basin). It is shown that both the disintegration and the cavitation treatment are efficient methods for controlling the fuel characteristics. Both methods allow increasing the degree of dispersion of the coal. The content of the small-sized particles reground by cavitation considerably exceeds the similar figure obtained using the disintegrator. The specific surface area of the coal is increased by both cavitation and disintegration with the cavitation treatment producing a considerably greater effect. Being subjected to the cavitation treatment, most coal particles assume the form of a split characterized by the thermodynamically nonequilibrium state. Under external action, in particular, of temperature, the morphological structure of such pulverized materials changes faster and, consequently, the combustion of the treated coal should occur more efficiently. The obtained results are explained from the physical point of view.

  18. Investigation into the structure of natural and regenerated humic-acid of high purity obtained from Hungarian brown coals

    Energy Technology Data Exchange (ETDEWEB)

    Korbuly, J.; Lakatos, B.; Sipos, S.

    1977-01-01

    Examines the purification of natural humic-acids obtained from lignites of Gyongyosvisonta and Varpalota, from brown coal of Dudar and that of regenerated humic-acid arising from the nitric acid treatment of lignite of Varpalota and gives detailed investigation into raw materials, intermediate products and purified humic-acids free of metal traces. On the basis of the average molecular weight, of the molecular weight distribution and of the chemical and physico-chemical characteristics significant structural differences of certain purified humic-acid sample can be experienced. These differences can be explained in case of natural humic-acids by the conditions of coalification and by the circumstances of formation of marsh and in case of regenerated humic-acids by the nitric acid treatment of lignite.

  19. Combustion studies of coal-derived solid fuels. Part IV. Correlation of ignition temperatures from thermogravimetry and free-floating experiments

    Science.gov (United States)

    Rostam-Abadi, M.; DeBarr, J.A.; Chen, W.T.

    1992-01-01

    The usefulness of TG as an efficient and practical method to characterize the combustion properties of fuels used in large-scale combustors is of considerable interest. Relative ignition temperatures of a lignite, an anthracite, a bituminous coal and three chars derived from this coal were measured by a free-floating technique. These temperatures were correlated with those estimated from TG burning profiles of the fuels. ?? 1992.

  20. Fiscal 1996 survey report on the environmentally friendly type coal utilization system feasibility study. Feasibility study of the environmentally friendly type coal utilization system in Thailand; Kankyo chowagata sekitan riyo system kanosei chosa. Tai ni okeru kankyo chowagata sekitan riyo system kanosei chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The paper investigated and studied the present situation and future trend of coal utilization and distribution in Thailand, and the present situation of environmental effects and the measures taken for environmental protection. Around 2010, coal will probably be produced only at EGAT`s Mae Moh (MM) coal mine. Demand for overseas coal is expected to be 40-50 million tons in 2011, and preparation of the coal center becomes a subject. For general industry use coal, pretreatment such as coal preparation, coal blending and briquetting is needed, considering coal quality, usage, transport distance and environmental effects. Brown coal of MM coal mine is a lignite with high sulfur, high ash content and low heating value. Wide spread of its use can be expected if upgrading is possible such as desulfurization, deashing, increasing heating value. In the electric power generation field, the absorber was installed at the existing boiler of the mine-mouth generating plant to conduct a verification test on high grade desulfurization of ultra-high sulfur lignite. In the industry field, the circulating fluidized bed boiler was adopted. In the residential/commercial field, introduction of briquette was proposed. 80 refs., 84 tabs.

  1. Fiscal 1996 survey report on the environmentally friendly type coal utilization system feasibility study. Feasibility study of the environmentally friendly type coal utilization system in Thailand; Kankyo chowagata sekitan riyo system kanosei chosa. Tai ni okeru kankyo chowagata sekitan riyo system kanosei chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The paper investigated and studied the present situation and future trend of coal utilization and distribution in Thailand, and the present situation of environmental effects and the measures taken for environmental protection. Around 2010, coal will probably be produced only at EGAT`s Mae Moh (MM) coal mine. Demand for overseas coal is expected to be 40-50 million tons in 2011, and preparation of the coal center becomes a subject. For general industry use coal, pretreatment such as coal preparation, coal blending and briquetting is needed, considering coal quality, usage, transport distance and environmental effects. Brown coal of MM coal mine is a lignite with high sulfur, high ash content and low heating value. Wide spread of its use can be expected if upgrading is possible such as desulfurization, deashing, increasing heating value. In the electric power generation field, the absorber was installed at the existing boiler of the mine-mouth generating plant to conduct a verification test on high grade desulfurization of ultra-high sulfur lignite. In the industry field, the circulating fluidized bed boiler was adopted. In the residential/commercial field, introduction of briquette was proposed. 80 refs., 84 tabs.

  2. Lignite zone as an indicator to lost circulation belt: a case study of ...

    African Journals Online (AJOL)

    Lignite zone as an indicator to lost circulation belt: a case study of some locations of Anambra State, ... Eighteen (18) water boreholes were studied for lost circulation. ... Journal of Applied Sciences and Environmental Management Vol.

  3. Humification processes in reclaimed open-cast lignite mine soils

    Energy Technology Data Exchange (ETDEWEB)

    Leiros, M.C.; Gil-Sotres, F.; Ceccanti, B.; Trasar-Cepeda, M.C.; Gonzales-Sangregorio, M.V. (Facultad de Farmacia de Santiago de Compostela, Santiago de Compostela (Spain). Departamento de Edafologia y Quimica Agraria)

    1993-10-01

    To identify the principal humification pathways which occur during the initial stages of pedogenesis, organic matter from mine soils of different ages from the Meirama lignite mine in NW Spain was subjected to a series of physicochemical and chemical fractionations. Although humic molecules of molecular weight lower than 10,000 Da were always predominant, the percentage of C associated with molecules of between 50,000 and 200,000 Da increased with soil age, as did the percentage of chemically stabilized humus and the percentage of C associated with immobile complexes. In general, these results suggest that the principal humification pathway in these soils involves abiotic condensation reactions, as in the case of natural soils of this region. The low complexed metal content of the mine soils in comparison with natural soils indicates the low degree of weathering of inorganic fraction which has occurred in the former.

  4. Aliphatic biological markers in Miocene Maritz-Iztok lignite, Bulgaria

    Energy Technology Data Exchange (ETDEWEB)

    Stefanova, M.; Magnier, C. [Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. of Organic Chemistry

    1997-12-31

    Chromatographic separation and mass spectral studies of bitumens extracted from lithotypes (humovitrain, xylain, liptain and humoclarain) from the Miocene Maritza-Iztok lignite reveal the following: (1) A preponderance of the {alpha}-phyllocladane skeleton over the pimaranes/abietanes. The variety of tricyclic diterpanes confirms that the generation biota included gymnosperms; (2) The presence of dicotyledonous angiosperms in the generation biota is indicated by the occurrence of widely distributed des-A-lupane structure; (3) The dominance of terpanes over steranes confirms the prevailing contribution of terrigenous input; (4) The preponderance of C{sub 27{beta}} hopane and the presence {beta}{beta} hopanes indicates a low degree of thermal maturation. 23 refs., 6 figs., 4 tabs.

  5. Peru: coal over the past three years: future trends. El desarrollo de la situacion del carbon en el Peru durante los ultimos tres anos y su evolucion

    Energy Technology Data Exchange (ETDEWEB)

    Dunin Borkoroski, E.; Goluchoweska, K.

    1989-01-01

    In 1985, annual coal production in Peru reached 150 to 200 mt and has since remained at roughly the same level. The coal comes from between 50 and 100 small and sometimes rather antiquated mining units which are run by small firms or individuals. Only a handful of coal mining operations are run by large companies and these too are small units. 85% of production is anthracite and the remainder bituminous coal. Only in rare cases is lignite or graphite mined and this only in very small quantities. Anthracite is mined in the Libertad, Ancash and Cajamarca departments, bituminous coal in Pasco and Junin and both types of coal in Lima and Arequipa. Current production patterns do not reflect the distribution and abundance of the coal. Coal has been found nearly everywhere in Peru and appears to have great potential whereas measured reserves are minimal and scattered across the country.

  6. Depolymerization of organosolv lignin using doped porous metal oxides in supercritical methanol

    NARCIS (Netherlands)

    Warner, Genoa; Hansen, Thomas S; Riisager, Anders; Beach, Evan S; Barta, Katalin; Anastas, Paul T

    An isolated, solvent-extracted lignin from candlenut (Aleurites moluccana) biomass was subjected to catalytic depolymerization in the presence of supercritical methanol, using a range of porous metal oxides derived from hydrotalcite-like precursors. The most effective catalysts in terms of lignin

  7. High-speed depolymerization at actin filament ends jointly catalysed by Twinfilin and Srv2/CAP.

    Science.gov (United States)

    Johnston, Adam B; Collins, Agnieszka; Goode, Bruce L

    2015-11-01

    Purified actin filaments depolymerize slowly, and cytosolic conditions strongly favour actin assembly over disassembly, which has left our understanding of how actin filaments are rapidly turned over in vivo incomplete. One mechanism for driving filament disassembly is severing by factors such as Cofilin. However, even after severing, pointed-end depolymerization remains slow and unable to fully account for observed rates of actin filament turnover in vivo. Here we describe a mechanism by which Twinfilin and Cyclase-associated protein work in concert to accelerate depolymerization of actin filaments by 3-fold and 17-fold at their barbed and pointed ends, respectively. This mechanism occurs even under assembly conditions, allowing reconstitution and direct visualization of individual filaments undergoing tunable, accelerated treadmilling. Further, we use specific mutations to demonstrate that this activity is critical for Twinfilin function in vivo. These findings fill a major gap in our knowledge of cellular disassembly mechanisms, and suggest that depolymerization and severing may be deployed separately or together to control the dynamics and architecture of distinct actin networks.

  8. High Speed Depolymerization at Actin Filament Ends Jointly Catalyzed by Twinfilin and Srv2/CAP

    Science.gov (United States)

    Johnston, Adam B.; Collins, Agnieszka; Goode, Bruce L.

    2015-01-01

    Purified actin filaments depolymerize slowly, and cytosolic conditions strongly favor actin assembly over disassembly, which has left our understanding of how actin filaments are rapidly turned over in vivo incomplete 1,2. One mechanism for driving filament disassembly is severing by factors such as Cofilin. However, even after severing, pointed end depolymerization remains slow and unable to fully account for observed rates of actin filament turnover in vivo. Here we describe a mechanism by which Twinfilin and Cyclase-associated protein work in concert to accelerate depolymerization of actin filaments by 3-fold and 17-fold at their barbed and pointed ends, respectively. This mechanism occurs even under assembly conditions, allowing reconstitution and direct visualization of individual filaments undergoing tunable, accelerated treadmilling. Further, we use specific mutations to demonstrate that this activity is critical for Twinfilin function in vivo. These findings fill a major gap in our knowledge of mechanisms, and suggest that depolymerization and severing may be deployed separately or together to control the dynamics and architecture of distinct actin networks. PMID:26458246

  9. Depolymerization of organosolv lignin using doped porous metal oxides in supercritical methanol

    NARCIS (Netherlands)

    Warner, Genoa; Hansen, Thomas S; Riisager, Anders; Beach, Evan S; Barta, Katalin; Anastas, Paul T

    2014-01-01

    An isolated, solvent-extracted lignin from candlenut (Aleurites moluccana) biomass was subjected to catalytic depolymerization in the presence of supercritical methanol, using a range of porous metal oxides derived from hydrotalcite-like precursors. The most effective catalysts in terms of lignin co

  10. Depolymerization of organosolv lignin to aromatic compounds over Cu-doped porous metal oxides

    NARCIS (Netherlands)

    Barta, Katalin; Warner, Genoa R.; Beach, Evan S.; Anastas, Paul T.

    2014-01-01

    Isolated, solvent-extracted lignin from candlenut (Aleurites moluccana) biomass was subjected to catalytic depolymerization in methanol with an added pressure of H-2, using a porous metal oxide catalyst (PMO) derived from a Cu-doped hydrotalcite-like precursor. The Cu-PMO was effective in converting

  11. Depolymerization of organosolv lignin to aromatic compounds over Cu-doped porous metal oxides

    NARCIS (Netherlands)

    Barta, Katalin; Warner, Genoa R.; Beach, Evan S.; Anastas, Paul T.

    2014-01-01

    Isolated, solvent-extracted lignin from candlenut (Aleurites moluccana) biomass was subjected to catalytic depolymerization in methanol with an added pressure of H-2, using a porous metal oxide catalyst (PMO) derived from a Cu-doped hydrotalcite-like precursor. The Cu-PMO was effective in converting

  12. Lewis acid-catalyzed depolymerization of soda lignin in supercritical ethanol/water mixtures

    NARCIS (Netherlands)

    Güvenatam, Burcu; Heeres, Erik H.J.; Pidko, Evgeny A.; Hensen, Emiel J M

    2016-01-01

    The depolymerization of lignin model compounds and soda lignin by super Lewis acidic metal triflates has been investigated in a mixture of ethanol and water at 400 °C. The strong Lewis acids convert representative model compounds for the structure-forming linkages in lignin, namely α-O-4, 5-O-4

  13. Lewis-acid catalyzed depolymerization of Protobind lignin in supercritical water and ethanol

    NARCIS (Netherlands)

    Guvenatam, Burcu; Heeres, Erik H.J.; Pidko, Evgeny A.; Hensen, Ernie J. M.

    2016-01-01

    The use of metal acetates, metal chlorides and metal triflates as Lewis acid catalysts for the depolymerization of soda lignin under supercritical conditions was investigated. The reactions were carried out at 400 degrees C in water and ethanol. Lignin conversion in supercritical water led to format

  14. Depolymerization of organosolv lignin using doped porous metal oxides in supercritical methanol

    NARCIS (Netherlands)

    Warner, Genoa; Hansen, Thomas S; Riisager, Anders; Beach, Evan S; Barta, Katalin; Anastas, Paul T

    2014-01-01

    An isolated, solvent-extracted lignin from candlenut (Aleurites moluccana) biomass was subjected to catalytic depolymerization in the presence of supercritical methanol, using a range of porous metal oxides derived from hydrotalcite-like precursors. The most effective catalysts in terms of lignin co

  15. Lewis-acid catalyzed depolymerization of Protobind lignin in supercritical water and ethanol

    NARCIS (Netherlands)

    Guvenatam, Burcu; Heeres, Erik H.J.; Pidko, Evgeny A.; Hensen, Ernie J. M.

    2016-01-01

    The use of metal acetates, metal chlorides and metal triflates as Lewis acid catalysts for the depolymerization of soda lignin under supercritical conditions was investigated. The reactions were carried out at 400 degrees C in water and ethanol. Lignin conversion in supercritical water led to

  16. Production and utilisation of a new pulverised fuel on bituminous coal/sewage sludge basis

    Energy Technology Data Exchange (ETDEWEB)

    Probst, H.H.; Wehland, P. [Bruno Fechner GmbH & Co. KG, Bottrop (Germany)

    1998-12-31

    Several solid fuels such as lignite, hard coal, sewage sludges and petrol coke were characterised by proximate and ultimate analyses, heavy metal content, calorific value etc. Thermogravimetric combustion profiles of five fuels were recorded to evaluate and compare the chemical reaction rates and behaviour. Combustion experiments on single fuels (coal and sewage sludge) and their blends were performed in a semi-technical high temperature drop tube furnace at DMT. The hard coal Middelburg, the Indonesian hard coal Kaltim Prima, the Colombian hard coal El Cerrejon, the sewage sludges Stadtwerke Dusseldorf and Emschergenossenschaft and their blends were tested with regard to their application in rotary kiln PF burners in the asphalt producing industry. The experiments varied reaction time and oxygen partial pressure. A fuel blend consisting of hard coals Kaltim Prima, Spitsbergen and El Cerrejon, respectively and sewage sludge Stadtwerke Dusseldorf (KPC/Dusseldorf 3:1) turned out to be suitable for industrial scale tests in an asphalt production plant competing with the standard fuel lignite fine dust Rheinbraun and pure sewage sludge Stadtwerke Dusseldorf. After a burner adaption phase to the novel fuels burner operation was stable. Heat introduction into the rotary kiln was best for the El Cerrejon/Dusseldorf (3:1) fuel blend. During operation with this blend all legal emission standards were met, whereas emission problems arose with sewage sludge Stadtwerke Dusseldorf. A fuel blend consisting of a high volatile hard coal and sewage sludge is an attractive substitute fuel for the expensive standard fuel lignite fine dust. 1 ref., 15 figs., 5 tabs.

  17. The Utilization of Peat, Lignite and Industrial Wastes in the Production of Mineral-Organic Fertilizers

    OpenAIRE

    Krystyna Hoffmann; Józef Hoffmann

    2007-01-01

    The results of chemical analyses of the composition of peat, lignite, turkey droppings and the potato industry effluent are presented. The results indicate that the substances can be used in mineral-organic fertilizer recipes. Although lignite and peat do not contain assimilable nutrients, from the ecology and pedology point of view they are valuable components of mineral-organic fertilizers. In order to determine the optimum turkey droppings and potato industry effluent dose in fertilizer bi...

  18. Preliminary geologic investigation of the West Glendive lignite deposits, Dawson County, Montana

    Science.gov (United States)

    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.

  19. THE INFLUENCE OF INCREASING RELIABILITY OF BELT CONVEYORS UPON THE PRODUCTIVITY OF LIGNITE QUARRIES

    Directory of Open Access Journals (Sweden)

    FLORIN-MIHAI NIȚESCU

    2012-10-01

    Full Text Available At present belt conveyors have an important role in the mines of lignite quarries because they contribute decisively to achieving an optimum production. From this point of view the management of mines should be constantly preoccupied with ensuring, in optimal conditions, the operation of these elements of fixed capital and, if it is necessary they should maintain constant reliability. In this context, this paper has as theme the relation between the reliability of conveyors and the productivity within lignite quarries.

  20. Epidemiological data base for a health effects study at a coal gasification plant

    OpenAIRE

    Morris, S C; Ukmata, H.; Begraca, M.; Canhasi, B.; Haxhiu, M.A.

    1988-01-01

    An occupational population is characterized as a basis for epidemiological study. Parameters include age, smoking history, years of work, job title, all medical diagnoses by 3-digit ICD code, and selected Iaboratory test results. By example analyses differences are examined in the incidence of chrome bronchitis and circulatory system disease by smoking history and job title. The data base includes coal gasification plant workers and surface lignite minors in Kosovo, Yugoslavia. Because of the...

  1. Characteristics of lignite seams in the Visonta opencast mine and analysis of relationships between their qualitative indices

    Energy Technology Data Exchange (ETDEWEB)

    Varga, J.

    1985-01-01

    Intercalations among the lignite seams consisting of clays and sandy clays considerably affect the quality indices of lignites themselves. The parameters (calorific value, ash content, etc.) show no homogeneous distribution in the opencast mine, thus their spatial changes should be followed. The analysis of the relationship of these parameters, e.g. the change of density as a function of water content, provides a useful tool to rationalize the lignite production.

  2. DEVELOPMENT OF CARBON PRODUCTS FROM LOW-RANK COALS

    Energy Technology Data Exchange (ETDEWEB)

    Edwin S. Olson

    2001-07-01

    The goal of this project is to facilitate the production of carbon fibers from low-rank coal (LRC) tars. To this end, the effect of demineralization on the tar yields and composition was investigated using high-sodium and high-calcium lignites commonly mined in North Dakota. These coals were demineralized by ion exchange with ammonium acetate and by cation dissolution with nitric acid. Two types of thermal processing were investigated for obtaining suitable precursors for pitch and fiber production. Initially, tars were produced by simple pyrolysis of the set of samples at 650 C. Since these experiments produced little usable material from any of the samples, the coals were heated at moderate temperatures (380 and 400 C) in tetralin solvent to form and extract the plastic material (metaplast) that forms at these temperatures.

  3. Proceedings of the third annual underground coal conversion symposium

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-01-01

    The Third Annual Underground Coal Conversion Symposium was held at Fallen Leaf Lake, CA, June 6--9, 1977. It was sponsored by the U.S. Department of Energy and hosted by Lawrence Livermore Laboratory. Forty-one papers have been entered individually into EDB and ERA; ten papers had been entered previously from other sources. The papers cover the in-situ gasification of lignite, subbituminous coal and bituminous coal, in flat lying seams and a steeply dipping beds, at moderate and at greater depths, and describe various technologies of (borehole linking, well spacings, gasifying agents (air, oxygen, steam, hydrogen, including mixtures). Measuring instruments for diagnostic and process control purposes are described. Environmental impacts (ground subsidence and possible groundwater pollution) are the subject of several papers. Finally, mathematical modelling and projected economics of the process are developed. (LTN)

  4. Energy Analysis of a Biomass Co-firing Based Pulverized Coal Power Generation System

    Directory of Open Access Journals (Sweden)

    Marc A. Rosen

    2012-03-01

    Full Text Available The results are reported of an energy analysis of a biomass/coal co-firing based power generation system, carried out to investigate the impacts of biomass co-firing on system performance. The power generation system is a typical pulverized coal-fired steam cycle unit, in which four biomass fuels (rice husk, pine sawdust, chicken litter, and refuse derived fuel and two coals (bituminous coal and lignite are considered. Key system performance parameters are evaluated for various fuel combinations and co-firing ratios, using a system model and numerical simulation. The results indicate that plant energy efficiency decreases with increase of biomass proportion in the fuel mixture, and that the extent of the decrease depends on specific properties of the coal and biomass types.

  5. Modelling of pyrolysis of coal-biomass blends using thermogravimetric analysis

    Energy Technology Data Exchange (ETDEWEB)

    Sadhukhan, A.K.; Gupta, P.; Goyal, T.; Saha, R.K. [National Institute for Technology, Durgapur (India).

    2008-11-15

    The primary objective of this work was to develop an appropriate model to explain the co-pyrolysis behaviour of lignite coal-biomass blends with different proportions using a thermogravimetric analyzer. A new parallel-series kinetic model was proposed to predict the pyrolysis behaviour of biomass over the entire pyrolysis regime, while a kinetic model similar to that of Anthony and Howard (Anthony, D.B., Howard, J.B., 1976. Coal devolatilization and hydrogasification. AIChE Journal 22(4), 625-656) was used for pyrolysis of coal. Analysis of mass loss history of blends showed an absence of synergistic effect between coal and biomass. Co-pyrolysis mass-loss profiles of the blends were predicted using the estimated kinetic parameters of coal and biomass. Excellent agreement was found between the predicted and the experimental results.

  6. Modelling of pyrolysis of coal-biomass blends using thermogravimetric analysis.

    Science.gov (United States)

    Sadhukhan, Anup Kumar; Gupta, Parthapratim; Goyal, Tripurari; Saha, Ranajit Kumar

    2008-11-01

    The primary objective of this work was to develop an appropriate model to explain the co-pyrolysis behaviour of lignite coal-biomass blends with different proportions using a thermogravimetric analyzer. A new parallel-series kinetic model was proposed to predict the pyrolysis behaviour of biomass over the entire pyrolysis regime, while a kinetic model similar to that of Anthony and Howard [Anthony, D.B., Howard, J.B., 1976. Coal devolatilization and hydrogasification. AIChE Journal 22(4), 625-656] was used for pyrolysis of coal. Analysis of mass loss history of blends showed an absence of synergistic effect between coal and biomass. Co-pyrolysis mass-loss profiles of the blends were predicted using the estimated kinetic parameters of coal and biomass. Excellent agreement was found between the predicted and the experimental results.

  7. Geological and Rock Mechanics Perspectives for Underground Coal Gasification in India

    Science.gov (United States)

    Singh, Ajay K.; Singh, Rajendra

    2017-07-01

    The geological resources of coal in India are more than 308 billion tonnes upto a depth of 1200 m, out of which proved reserve has been reported at around 130 billion tonnes. There is an increasing requirement to increase the energy extraction efficiency from coal as the developmental prospects of India increase. Underground coal gasification (UCG) is a potential mechanism which may be utilized for extraction of deep-seated coal reserves. Some previous studies suggest that lignites from Gujarat and Rajasthan, along with tertiary coals from northeastern India can be useful from the point of view of UCG. We discuss some geological literature available for these areas. Coming to the rock mechanics perspectives, during UCG the rock temperature is considerable high. At this temperature, most empirical models of rock mechanics may not be applied. In this situation, the challenges for numerical modelling of UCG sites increases manifold. We discuss some of the important modelling geomechanical issues related to UCG in India.

  8. A short report of the investigations made on the facies of German coal deposits

    Energy Technology Data Exchange (ETDEWEB)

    Dehmer, Janet [An den Rothen 96, D-97080 Wurzburg (Germany)

    2004-04-23

    In 1996, Commission II of the ICCP set up a coal facies working group. The first step was to collate literature on coal facies analysis for different countries. This report provides an overview on the investigations made on the facies interpretations of German coal deposits over the last 50 years with an emphasis on Tertiary coals. It outlines the major deposits present in Germany and gives the main facies interpretations of coals of lignite and bituminous rank. Furthermore, it points out that there lies a certain ambiguity in the interpretation of specific maceral associations, which could confuse facies analyses without the support of interdisciplinary studies and thus suggests that the working group should address this point for future work.

  9. Validation of a FBC model for co-firing of hazelnut shell with lignite against experimental data

    Energy Technology Data Exchange (ETDEWEB)

    Kulah, Gorkem [Middle East Technical University, Department of Chemical Engineering, 06531 Ankara (Turkey)

    2010-07-15

    Performance of a comprehensive system model extended for modelling of co-firing of lignite and biomass was assessed by applying it to METU 0.3 MW{sub t} Atmospheric Bubbling Fluidized Bed Combustor co-firing lignite with hazelnut shell and validating its predictions against on-line temperature and concentration measurements of O{sub 2}, CO{sub 2}, CO, SO{sub 2} and NO along the same test rig fired with lignite only, lignite with limestone addition and lignite with biomass and limestone addition. The system model accounts for hydrodynamics; volatiles release and combustion, char combustion, particle size distribution for lignite and biomass; entrainment; elutriation; sulfur retention and NO formation and reduction, and is based on conservation equations for energy and chemical species. Special attention was paid to different devolatilization characteristics of lignite and biomass. A volatiles release model based on a particle movement model and a devolatilization kinetic model were incorporated into the system model separately for both fuels. Kinetic parameters for devolatilization were determined via thermogravimetric analysis. Predicted and measured temperatures and concentrations of gaseous species along the combustor were found to be in good agreement. Introduction of biomass to lignite was found to decrease SO{sub 2} emissions but did not affect NO emissions significantly. The system model proposed in this study proves to be a useful tool in qualitatively and quantitatively simulating the processes taking place in a bubbling fluidized bed combustor burning lignite with biomass. (author)

  10. The effect of lignite on nitrogen mobility in a low-fertility soil amended with biosolids and urea.

    Science.gov (United States)

    Paramashivam, Dharini; Clough, Tim J; Carlton, Anna; Gough, Kelsi; Dickinson, Nicholas; Horswell, Jacqui; Sherlock, Robert R; Clucas, Lynne; Robinson, Brett H

    2016-02-01

    Lignite has been proposed as a soil amendment that reduces nitrate (NO3(-)) leaching from soil. Our objective was to determine the effect of lignite on nitrogen (N) fluxes from soil amended with biosolids or urea. The effect of lignite on plant yield and elemental composition was also determined. Batch sorption and column leaching experiments were followed by a lysimeter trial where a low fertility soil was amended with biosolids (400 kg N/ha equivalent) and urea (200 kg N/ha equivalent). Treatments were replicated three times, with and without lignite addition (20 t/ha equivalent). Lignite did not reduce NO3(-) leaching from soils amended with either biosolids or urea. While lignite decreased NO3(-) leaching from an unamended soil, the magnitude of this effect was not significant in an agricultural context. Furthermore, lignite increased cumulative N2O production from soils receiving urea by 90%. Lignite lessened the beneficial growth effects of adding biosolids or urea to soil. Further work could investigate whether coating urea granules with lignite may produce meaningful environmental benefits.

  11. Surface restructuring of lignite by bio-char of Cuminum cyminum - Exploring the prospects in defluoridation followed by fuel applications

    Science.gov (United States)

    Msagati, T. A. M.; Mamba, B. B.; Sivasankar, V.; Omine, Kiyoshi

    2014-05-01

    Recently, there has been an interest in the areas of developing new carbon materials for fluoride removal applications. The development of new carbon materials is of recent choice which involves the synthesis of hybrid carbon from various sources. In this context, the present contribution is made to focus on the study the restructured surface of lignite using a bio-material called Cuminum cyminum. The restructured lignite (RSL) was synthesized with an improved carbon content of 13% and its BET surface area was found to be 3.12 times greater than lignite (L). The amorphous nature of lignite and RSL was quite explicable from XRD studies. SEM studies exhibited a fibrous and finer surface of lignite which was well restructured into a semi-melt (5 μm) surface for RSL. Defluoridation potential of Restructured Lignite (15.8 mg g-1) was greater than the lignite (13.8 mg g-1) at pH 7.93 ± 0.03. Kinetic and isotherm parameters derived from various models helped in comprehending the nature and dynamics of fluoride sorption. Both the normal and the restructured lignite were found to be consistent with its fluoride uptake of 57% and 60% respectively even after fifth cycle of regeneration. High heating values of 22.01 MJ kg-1 and 26.90 MJ kg-1 respectively for lignite and RSL deemed their additional application as fuel materials.

  12. A new cost-effective method to mitigate ammonia loss from intensive cattle feedlots: application of lignite

    Science.gov (United States)

    Chen, Deli; Sun, Jianlei; Bai, Mei; Dassanayake, Kithsiri B.; Denmead, Owen T.; Hill, Julian

    2015-11-01

    In open beef feedlot systems, more than 50% of dietary nitrogen (N) is lost as ammonia (NH3). Here we report an effective and economically-viable method to mitigate NH3 emissions by the application of lignite. We constructed two cattle pens (20 × 20 m) to determine the effectiveness of lignite in reducing NH3 emissions. Twenty-four steers were fed identical commercial rations in each pen. The treatment pen surface was dressed with 4.5 kg m-2 lignite dry mass while no lignite was applied in the control pen. We measured volatilised NH3 concentrations using Ecotech EC9842 NH3 analysers in conjunction with a mass balance method to calculate NH3 fluxes. Application of lignite decreased NH3 loss from the pen by approximately 66%. The cumulative NH3 losses were 6.26 and 2.13 kg N head-1 in the control and lignite treatment, respectively. In addition to the environmental benefits of reduced NH3 losses, the value of retained N nutrient in the lignite treated manure is more than $37 AUD head-1 yr-1, based on the current fertiliser cost and estimated cost of lignite application. We show that lignite application is a cost-effective method to reduce NH3 loss from cattle feedlots.

  13. Mobilization of iron from coal fly ash was dependent upon the particle size and the source of coal.

    Science.gov (United States)

    Smith, K R; Veranth, J M; Lighty, J S; Aust, A E

    1998-12-01

    Particulate air pollution, including coal fly ash, contains iron, and some of the pathological effects after inhalation may be due to reactive oxygen species produced by iron-catalyzed reactions. The objective of this study was to determine whether iron, present in coal fly ash, was mobilized, leading to ferritin induction in human airway epithelial cells, and whether the size of the particles affected the amount of iron mobilized. Three types of coal were used to generate the three size fractions of fly ash collected. The Utah coal fly ash was generated from a bituminous b coal, the Illinois coal fly ash from a bituminous c coal, and the North Dakota coal fly ash from a lignite a coal. Three size fractions were studied to compare the amount of iron mobilized in human airway epithelial (A549) cells and by citrate in cell-free suspensions. The size fractions selected were fine (airborne particulate matter fraction greater than 10 microm. Coal fly ash samples were incubated with 1 mM citrate to determine if iron associated with coal fly ash could be mobilized. Iron was mobilized by citrate from all three size fractions of all three coal types to levels as high as 56.7 nmol of Fe/mg of coal fly ash after 24 h. With all three coal types, more iron was mobilized by citrate from the fraction than from the >2.5 microm fractions. Further, the mobilized iron was in the Fe(III) form. To determine if iron associated with the coal fly ash could be mobilized by A549 cells, cells were treated with coal fly ash, and the amount of the iron storage protein ferritin was determined after 24 h. Ferritin levels were increased by as much as 11.9-fold in cells treated with coal fly ash. With two of the three types of coal studied, more ferritin was induced in cells treated with the fraction than with the >2.5 microm fractions. Further, inhibition of the endocytosis of the coal fly ash by the cells resulted in ferritin levels that were near that of the untreated cells, suggesting that

  14. Thermolysis of phenethyl phenyl ether: A model of ether linkages in low rank coal

    Energy Technology Data Exchange (ETDEWEB)

    Britt, P.F.; Buchanan, A.C. III; Malcolm, E.A.

    1994-09-01

    Currently, an area of interest and frustration for coal chemists has been the direct liquefaction of low rank coal. Although low rank coals are more reactive than bituminous coals, they are more difficult to liquefy and offer lower liquefaction yields under conditions optimized for bituminous coals. Solomon, Serio, and co-workers have shown that: in the pyrolysis and liquefaction of low rank coals, a low temperature cross-linking reaction associated with oxygen functional groups occurs before tar evolution. A variety of pretreatments (demineralization, alkylation, and ion-exchange) have been shown to reduce these retrogressive reactions and increase tar yields, but the actual chemical reactions responsible for these processes have not been defined. In order to gain insight into the thermochemical reactions leading to cross-linking in low rank coal, we have undertaken a study of the pyrolysis of oxygen containing coal model compounds. Solid state NMR studies suggest that the alkyl aryl ether linkage may be present in modest amounts in low rank coal. Therefore, in this paper, we will investigate the thermolysis of phenethyl phenyl ether (PPE) as a model of 0-aryl ether linkages found in low rank coal, lignites, and lignin, an evolutionary precursor of coal. Our results have uncovered a new reaction channel that can account for 25% of the products formed. The impact of reaction conditions, including restricted mass transport, on this new reaction pathway and the role of oxygen functional groups in cross-linking reactions will be investigated.

  15. Development of standards and a cost model for coal agglomeration and related studies

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, S.G.; Kuby, O.A.; Korosi, F.A.; Paulin, M.O.

    1982-02-26

    Several topics concerning coal agglomeration and fixed-bed coal gasification, as they relate to an agglomeration-process development program presently being performed for the Department of Energy, are discussed in this report. Specific topics include an examination of the performance of coals in fixed-bed gasifiers, the development of properties' standards by which agglomerates produced in the program may be compared, the development of a cost model to judge the economic feasibility of coal agglomeration for potential users and the maximum binder levels to be considered in the program, the definition of a suitable briquette size for coal gasification, and a study of upgrading methods at the mines to improve agglomeration. Extensive property data and the results of a number of special tests on six coals (Pittsburgh No. 8 bituminous coal, Illinois No. 6 bituminous coal, Wyoming Bighorn subbituminous coal, Montana Rosebud No. 14 subbituminous coal, North Dakota Indian Head lignite and Pennsylvania Nanoth anthracite coal) and on FMC formcoke and Simplex briquettes are reported.

  16. Using ground and intact coal Samples to evaluate hydrocarbon fate during supercritical CO2 injection into coal beds: effects of particle size and coal moisture

    Science.gov (United States)

    Kolak, Jon; Hackley, Paul C.; Ruppert, Leslie F.; Warwick, Peter D.; Burruss, Robert

    2015-01-01

    To investigate the potential for mobilizing organic compounds from coal beds during geologic carbon dioxide (CO2) storage (sequestration), a series of solvent extractions using dichloromethane (DCM) and using supercritical CO2 (40 °C and 10 MPa) were conducted on a set of coal samples collected from Louisiana and Ohio. The coal samples studied range in rank from lignite A to high volatile A bituminous, and were characterized using proximate, ultimate, organic petrography, and sorption isotherm analyses. Sorption isotherm analyses of gaseous CO2 and methane show a general increase in gas storage capacity with coal rank, consistent with findings from previous studies. In the solvent extractions, both dry, ground coal samples and moist, intact core plug samples were used to evaluate effects of variations in particle size and moisture content. Samples were spiked with perdeuterated surrogate compounds prior to extraction, and extracts were analyzed via gas chromatography–mass spectrometry. The DCM extracts generally contained the highest concentrations of organic compounds, indicating the existence of additional hydrocarbons within the coal matrix that were not mobilized during supercritical CO2 extractions. Concentrations of aliphatic and aromatic compounds measured in supercritical CO2 extracts of core plug samples generally are lower than concentrations in corresponding extracts of dry, ground coal samples, due to differences in particle size and moisture content. Changes in the amount of extracted compounds and in surrogate recovery measured during consecutive supercritical CO2extractions of core plug samples appear to reflect the transition from a water-wet to a CO2-wet system. Changes in coal core plug mass during supercritical CO2 extraction range from 3.4% to 14%, indicating that a substantial portion of coal moisture is retained in the low-rank coal samples. Moisture retention within core plug samples, especially in low-rank coals, appears to inhibit

  17. Coal induced production of a rhamnolipid biosurfactant by Pseudomonas stutzeri, isolated from the formation water of Jharia coalbed.

    Science.gov (United States)

    Singh, Durgesh Narain; Tripathi, Anil Kumar

    2013-01-01

    A strain of Pseudomonas stutzeri was isolated form an enrichment of perchlorate reducing bacteria from the formation water collected from an Indian coalbed which solubilized coal and produced copious amount of biosurfactant when coal was added to the medium. It produced maximum biosurfactant with lignite coal followed by olive oil and soybean oil which was able to emulsify several aromatic hydrocarbons including kerosene oil, diesel oil, hexane, toluene etc. Haemolytic test, growth inhibition of Bacillus subtilis and FTIR analysis showed rhamnolipid nature of the biosurfactant. The stability of the coal induced biosurfactant in pH range of 4-8 and up to 25% NaCl concentration and 100 °C temperature suggests that due to its ability to produce biosurfactant and solubilize coal P. stutzeri may be useful in the coalbed for in situ biotransformation of coal into methane and in the bioremediation of PAHs from oil contaminated sites including marine environments.

  18. Proximate analysis of coal and solid products from coal conversion by thermogravimetric analysis

    Energy Technology Data Exchange (ETDEWEB)

    Iacchelli, A.; Selucky, M.

    1983-01-01

    Proximate analysis of coals consists of the determination of moisture, volatile matter, ash and fixed carbon in a sample. This report shows that this analysis can be accomplished using thermal gravimetric analysis (TGA) as a procedure which can simulate all conditions involved. The influence of various variables, such as sample size, purge gas flow rate, temperature program and coal rank have been studied using coal samples ranging in rank from low volatile bituminous coals to lignites. The TGA procedure practically eliminates sample contact with ambient air and reduces sample handling to detemining (automatically) its original weight before the start of the analysis. The whole proximate analysis is essentially a one-step procedure. The use of oxygen after volatile matter removal allows direct burning of fixed carbon as a direct determination of its weight. The method is fast and well repeatable and is recommended as a semiroutine procedure, especially for very small samples from minibomb experiments, or where additional information on the course of sample devolatilization is of interest, such as in the analysis of pyridine and toluene extracts and the various insoluble materials form coal conversion experiments. 7 refs., 13 figs., 4 tabs.

  19. Behaviour of inorganic matter during heating of Bulgarian coals

    Energy Technology Data Exchange (ETDEWEB)

    Vassileva, Christina G.; Vassilev, Stanislav V. [Central Laboratory of Mineralogy and Crystallography, Acad. G. Bonchev Str., Bl. 107, Bulgarian Academy of Sciences, Sofia 1113 (Bulgaria)

    2006-12-15

    Bulgarian subbituminous (Pernik, Bobov Dol) and bituminous (Balkan) coals were gradually heated under air from 100 {sup o}C to their fluid ash-fusion temperatures (1400-1600 {sup o}C) via 100 {sup o}C intervals and the behaviour of their inorganic matter (IM) was studied. The original minerals and newly formed inorganic phases in the oxidation and combustion products (OCPs) of these coals were identified and the behaviour of 33 minerals and phases was described. The coals studied reveal high detrital abundance and low authigenic mineralization with sulphide-sulphate, carbonate or mixed sulphide-sulphate and carbonate tendencies. The IM of coals is composed mainly of quartz, kaolinite, illite+muscovite, feldspars, pyrite, and calcite, while the other minerals identified have subordinate occurrence. The IM of OCPs includes various pre-existing minerals and newly formed phases. The latter phases are glass, quartz-cristobalite-tridymite, mullite, amorphous clay material, hematite-magnetite, anhydrite, and others originating from the heating of these coals or storage of their OCPs. The physico-chemical processes and temperatures that result in the formation of new phases in OCPs are described. The relationships between the ash-fusion behaviour and chemical and mineral composition of the coals are also discussed. A systematization of the physico-chemical transformations and some comparative characterizations, as well as prediction of certain technological and environmental problems related to the behaviour of IM during heating of Bulgarian lignites, subbituminous and bituminous coals are also described and summarized. (author)

  20. RECULTIVATION AND SUSTAINABLE DEVELOPMENT OF COAL MINING IN KOLUBARA BASIN

    Directory of Open Access Journals (Sweden)

    Ivica M Ristović

    2010-01-01

    Full Text Available Coal plays a fundamental role in global development, but the coal mining industry exerts impact on the environment, society and economy. Kolubara Coal Company produces about 30 million tonnes of coal, and digs about 70 million m3 of overburden per year. The main result of surface coal is certainly taking agricultural land, so that surface mines, which affect large areas in Kolubara, about 100 hectars a year, causing a number of problems related to the recultivation of degraded area after coal extraction. The lignite extraction through the method of opencast mining in Kolubara is about 60 years old. The previous exploitation usage is characterised by the fact that the disposal of overburden is made non-selectively, whereas the surface solum is not being preserved. The recultivation is carried out in parallel with overburden excavation. It is necessary to preserve the fertile solum through selective excavation in order to bring the soil back to its previous purpose - agricultural production. The objective of this paper is mainly to point out the need for the further expansion of the utilisation of fossil fuels, which in turn reduces the emission of CO2, and thus reduces or prevents global climate changes on Earth. In addition to that, bringing back deteriorated terrains to their previous purpose - agricultural production, or the afforestation - contributes to the maintenance of ecological balance in nature, which then makes coal mining sustainable.

  1. Results of core drilling for uranium-bearing lignite, Mendenhall area, Harding County, South Dakota

    Science.gov (United States)

    Gill, James R.

    1954-01-01

    Core drilling for data on uranium-bearing lignite in the Mendenhall area, Harding County, S. Dak. , was conducted by the U. S. Bureau of Mines during the period October 1952 to July 1953. Forty-two core holes totaling 9, 683 feet drilled in an area of about six square miles indicate a reserve of about 127/000,000 tons of lignite of which about 49,000,000 tons contain an average of 0.005 percent uranium or more. The Mendenhall area is near the center of the Slim Buttes, which are about 30 miles long from north to south. The uranium-bearing lignite averages, 5. 4 feet in thickness and occurs in the Ludlow member of the Fort Union formation of Paleocene age. Fuel analyses of about 130 samples indicate that the lignite contains about 15 percent ash, 36.7 percent moisture, 24r percent fixed carbon, 23.9 percent volatile matter, and 1.5 percent sulfur and has heating values of about 5,800 btu (as received). Uranium analyses of about 700 samples of lignite core indicate that about 2, 790 tons of uranium are present in the Mendenhall area. Inferred uranium reserves of 2,335 and .1. 050 tons are indicated by grade cutoffs of 0. 005 and 0. 01 percent uranium in the lignites, and 2, 065 and l s 35Stons are indicated by grade cutoffs of 0.03 and 0.05 percent uranium in the lignite ash. The above grade cutoffs have been incorporated on maps showing areal distribution:

  2. Large scale solubilization of coal and bioconversion to utilizable energy. Seventh quarterly technical progress report, April 1, 1995--June 30, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, N.C.

    1995-12-01

    In order to develop a system for a large scale coal solubilization and its bioconversion to utilizable fuel, we plan to clone the genes encoding Neurospora protein that facilitate depolymerization of coal. We also plan to use desulfurizing bacteria to remove the sulfur in situ and use other microorganisms to convert biosolubilized coal into utilizable energy following an approach utilizing several microorganisms. In addition the product of coal solubilized by fungus will be characterized to determine their chemical nature and the mechanism of reaction catalyzed by fungal product during in vivo and in vitro solubilization by the fungus or purified fungal protein.

  3. Large scale solubilization of coal and bioconversion to utilizable energy. Eighth quarterly technical progress report, July 1, 1995--September 30, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, N.C.

    1996-02-01

    In order to develop a system for a large scale coal solubilization and its bioconversion to utilizable fuel, we plan to clone the genes encoding Neurospora protein that facilitate depolymerization of coal. We also plan to use desulfurizing bacteria to remove the sulfur in situ and use other microorganisms to convert biosolubilized coal into utilizable energy following an approach utilizing several microorganisms. In addition the product of coal solubilized by fungus will be characterized to determine their chemical nature and the mechanism of reaction catalyzed by fungal product during in vivo and in vitro solubilization by the fungus or purified fungal protein.

  4. Steam pretreatment for coal liquefaction

    Science.gov (United States)

    Ivanenko, Olga

    The objectives of this work are to test the application of steam pretreatment to direct coal liquefaction, to investigate the reaction of model compounds with water, and to explore the use of zeolites in these processes. Previous work demonstrated the effectiveness of steam pretreatment in a subsequent flash pyrolysis. Apparently, subcritical steam ruptures nearly all of the ether cross links, leaving a partially depolymerized structure. It was postulated that very rapid heating of the pretreated coal to liquefaction conditions would be required to preserve the effects of such treatment. Accordingly, a method was adopted in which coal slurry is injected into a hot autoclave containing solvent. Since oxygen is capable of destroying the pretreatment effect, precautions were taken for its rigorous exclusion. Tests were conducted with Illinois No. 6 coal steam treated at 340sp°C, 750 psia for 15 minutes. Both raw and pretreated samples were liquified in deoxygenated tetralin at high severity (400sp°C, 30 min.) and low severity (a: 350sp°C, 30 min., and b: 385sp°C, 15 min.) conditions under 1500 psia hydrogen. Substantial improvement in liquid product quality was obtained and the need for rapid heating and oxygen exclusion demonstrated. Under low severity conditions, the oil yield was more than doubled, going from 12.5 to 29 wt%. Also chemistry of the pretreatment process was studied using aromatic ethers as model compounds. alpha-Benzylnaphthyl ether (alpha-BNE), alpha-naphthylmethyl phenyl (alpha-NMPE), and 9-phenoxyphenanthrene were exposed to steam and inert gas at pretreatment conditions and in some cases to liquid water at 315sp°C. alpha-BNE and alpha-NMPE showed little difference in conversion in inert gas and in steam. Hence, these compounds are poor models for coal in steam pretreatment. Thermally stable 9-phenoxyphenanthrene, however, was completely converted in one hour by liquid water at 315sp°C. At pretreatment conditions mostly rearranged starting

  5. 扩散条件下褐煤正向阴燃特性的初步研究%Preliminary Study on the characteristics of Lignite forward smoldering under diffusion

    Institute of Scientific and Technical Information of China (English)

    张世明; 李建章; 曹华

    2012-01-01

    Based on the theory of heat transfer and ventilation, the temperature data of the forward smoldering process and the gas concentra tion data are obtained in real time by using self-designed test bed brown coal combustion and smoldering combustion test. By analyzing the physical properties of lignite, smoldering temperature data and phenomenon, the characteristics of lignite that forward smoldering ignition, fire endurance and propagation are proposed. The results show that the characteristics of lignite are easy to ignite, spread slowly, the high temper- ature to maintain a long time, and also can keep tinder, which usually can pose a significant security risk for the undergTound coal mines.%基于传热学及燃烧学理论,用自行设计的阴燃实验装置对褐煤进行了正向阴燃实验,主要是针对正向阴燃过程中的温度及特征气体浓度变化进行了连续测定。通过分析实验数据,研究了褐煤正向阴燃时的引燃特性、耐火性和传播特性。研究结果表明,褐煤具有易引燃、阴燃传播速度慢、高温维持时间长、保存火种能力强的特点,通常是地下煤矿的一个重大安全隐患。

  6. 轻度热解提质褐煤孔结构研究%Pore structure of mild pyrolysis of upgrading lignite

    Institute of Scientific and Technical Information of China (English)

    叶普海; 周敏; 刘恭欣; 钱春梅; 杨絮; 陈恒宝

    2012-01-01

    Based on the TGA analysis of Huolinhe lignite, experiments were performed to explore the process of slight pyrolysis in the tube furnace. Low-temperature nitrogen adsorption methods were used to study the pore characteristics of the coal sample before and after pyrolysis. Influences of different of pyrolysis temperature and constant temperature time on the coal pore structure were investigated. The results shows that pyrolysis temperature and constant temperature time have significant influences on the pore structure distribution, the adsorption and desorption isotherms are not coincident while the difference of raw coal is greater which indicates the upgraded coal has fewer microspores and more larger-pores. Compared with the raw coal, surface area and pore volume decrease and average pore size increased after slight pyrolysis.%对霍林河褐煤热重分析的基础上,在管式炉中进行轻度热解实验,通过低温N2吸附研究了热解前后煤样的孔隙特性,考察不同热解温度,恒温时间对煤孔结构的影响.结果表明:热解温度和恒温时间对褐煤的孔结构分布影响较大.褐煤和提质煤的吸附脱附等温曲线都存在吸附回线,但褐煤比提质褐煤的吸附回线宽,说明提质煤的微孔数量减少,大孔数量增多.与褐煤相比,轻度热解处理后,褐煤的比表面积减少,孔容减小,平均孔径增大.

  7. Environmental assessment of no remedial action at the inactive uraniferous lignite ashing sites at Belfield and Bowman, North Dakota

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    The Belfield and Bowman sites were not included on the original congressional list of processing sites to be designated by the Secretary of Energy. Instead, the sites were nominated for designation by the Dakota Resource Council in a letter to the DOE (September 7, 1979). In a letter to the DOE (September 12, 1979), the state of North Dakota said that it did not believe the sites would qualify as processing sites under the Uranium Mill Tailings Radiation Control Act (UMTRCA) because the activities at the sites involved only the ashing of uraniferous lignite coal and the ash was shipped out of state for actual processing. Nevertheless, on October 11, 1979, the state of North Dakota agreed to the designation of the sites because they met the spirit of the law (reduce public exposure to radiation resulting from past uranium operations). Therefore, these sites were designated by the Secretary of Energy for remedial action. Because of the relatively low health impacts determined for these sites, they were ranked as low priority and scheduled to be included in the final group of sites to be remediated.

  8. Baseline risk assessment of ground water contamination at the inactive uriniferous lignite ashing site near Belfield, North Dakota

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-08-01

    This Baseline Risk Assessment of Ground Water Contamination at the Inactive Uraniferous Lignite Ashing Site Near Belfield, North Dakota, evaluates potential impacts to public health or the environment resulting from ground water contamination at the site where coal containing uranium was burned to produce uranium. The US Department of Energy`s Uranium Mill Tailings Remedial Action (UMTRA) Project is evaluating plans to remedy soil and ground water contamination at the site. Phase I of the UMTRA Project consists of determining the extent of soil contamination. Phase II of the UMTRA Project consists of evaluating ground water contamination. Under Phase II, results of this risk assessment will help determine what remedial actions may be necessary for contaminated ground water at the site. This risk assessment evaluates the potential risks to human health and the environment resulting from exposure to contaminated ground water as it relates to historic processing activities at the site. Potential risk is quantified for constituents introduced from the processing activities, and not for those constituents naturally occurring in water quality in the site vicinity. Background ground water quality has the potential to cause adverse health effects from exposure through drinking. Any risks associated with contaminants attributable to site activities are incremental to these risks from background ground water quality. This incremental risk from site-related contaminants is quantified in this risk assessment. The baseline risk from background water quality is incorporated only into the assessment of potential chemical interactions and the definition of the overall site condition.

  9. Toxic emissions during co-combustion of biomass-waste wood-lignite blends in an industrial boiler.

    Science.gov (United States)

    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.

  10. Fuel retrofitting possibilities in pulverised brown coal power plants towards reduction of CO{sub 2} emissions

    Energy Technology Data Exchange (ETDEWEB)

    Agraniotis, Michalis

    2012-07-01

    The thesis intends to assess the potential of two different brown coal substitution concepts as possible options to reduce CO{sub 2} emissions in existing pulverised brown coal power plants. The substitution of brown coal by Solid Recovered Fuels (SRF) is examined as first concept. The second concept regarded is the integration of a lignite pre-drying system in an existing steam cycle and the substitution of raw brown coal by pre-dried brown coal. SRF co-firing is demonstrated in a 600 MWe pulverised brown coal boiler in Germany, while pre-dried brown coal co-firing is demonstrated in a 75 MWth pulverised lignite boiler in Greece. Specific environmental, technological and economic parameters are used for the evaluation according to a multi-criteria analysis approach. The analysis tools adopted include experimental measurement activities in the industrial and semi industrial scale, 3D numerical simulations (CFD), thermodynamic calculations of power plant steam cycles and financial calculations. (orig.)

  11. Climate, decay, and the death of the coal forests.

    Science.gov (United States)

    Hibbett, David; Blanchette, Robert; Kenrick, Paul; Mills, Benjamin

    2016-07-11

    After death, most of the biological carbon in organisms (Corg) is returned to the atmosphere as CO2 through the respiration of decomposers and detritivores or by combustion. However, the balance between these processes is not perfect, and when productivity exceeds decomposition, carbon sequestration results. An unparalleled interval of carbon sequestration in Earth's history occurred during the Late Carboniferous (Pennsylvanian) and Permian Periods (ca. 323-252 Ma), when arborescent vascular plants related to living club mosses (Lycophytes), ferns (Monilophytes), horsetails (Equisetophytes) and seed plants (Spermatophytes) formed extensive forests in coastal wetlands. On their death, these plants became buried in sediments, where they transformed into peat, lignite, and, finally, coal.

  12. Usage of fly ash as a coal desulphurization reagent

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Kuecuekbayrak, S. [Istanbul Technical Univ. (Turkey). Chemical and Metallurgical Engineering Faculty

    1996-12-31

    This paper covers the direct usage of fly ash to remove sulphur from coal. Experiments were carried out on a high sulphur Turkish lignite. 5 g of fly ash was extracted in 200 ml of water under pressure and the dilute solution containing water extractable parts of fly ash was used as desulphurization reagent. Oxygen pressure was created over desulphurization medium during the extraction period by which dissolved oxygen was concentrated in the solution. Effects of temperature, partial pressure of oxygen, and time were investigated in the ranges of 403--498 K, 0.0--1.5 MPa and 15--90 min, respectively.

  13. Rapid room temperature solubilization and depolymerization of polymeric lignin at high loadings

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jian; Dutta, Tanmoy; Parthasarathi, Ramakrishnan; Kim, Kwang Ho; Tolic, Nikola; Chu, Rosalie K.; Isern, Nancy G.; Cort, John R.; Simmons, Blake A.; Singh, Seema

    2016-10-03

    The relatively poor solubility of lignin in most pretreatment solvents remains one of the biggest challegnes in lignin valorization to improve overall biorefinery economics. In this work, rapid room temperature solubilization of lignin at high solid loadings (>30 wt%) can be easily achieved in a single step using ethylene glycol (EG). The solubilized lignin can be rapidly and quantitively recovered with the addtion of ethanol. The computational and nuclear magnetic resonance (NMR) spectroscopic studies confirm that strong hydrogen bond interactions between EG and the free hydroxyl groups present in lignin contribute to the lignin dissolution. In addition, hydrogen peroxide mediated depolymerization of dissolved lignin at low temperature (80 oC) was tested and the effect of EG molecules on depolymerization of ligin was also theoritically studied. The findings of this work provide mechanistic insights of hydrogen bond interactions in high lignin solubilization and valorization.

  14. Tandem Catalytic Depolymerization of Lignin by Water-Tolerant Lewis Acids and Rhodium Complexes.

    Science.gov (United States)

    Jastrzebski, Robin; Constant, Sandra; Lancefield, Christopher S; Westwood, Nicholas J; Weckhuysen, Bert M; Bruijnincx, Pieter C A

    2016-08-23

    Lignin is an attractive renewable feedstock for aromatic bulk and fine chemicals production, provided that suitable depolymerization procedures are developed. Here, we describe a tandem catalysis strategy for ether linkage cleavage within lignin, involving ether hydrolysis by water-tolerant Lewis acids followed by aldehyde decarbonylation by a Rh complex. In situ decarbonylation of the reactive aldehydes limits loss of monomers by recondensation, a major issue in acid-catalyzed lignin depolymerization. Rate of hydrolysis and decarbonylation were matched using lignin model compounds, allowing the method to be successfully applied to softwood, hardwood, and herbaceous dioxasolv lignins, as well as poplar sawdust, to give the anticipated decarbonylation products and, rather surprisingly, 4-(1-propenyl)phenols. Promisingly, product selectivity can be tuned by variation of the Lewis-acid strength and lignin source. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  15. Selective and recyclable depolymerization of cellulose to levulinic acid catalyzed by acidic ionic liquid.

    Science.gov (United States)

    Ren, Huifang; Girisuta, Buana; Zhou, Yonggui; Liu, Li

    2015-03-01

    Cellulose depolymerization to levulinic acid (LA) was catalyzed by acidic ionic liquids (ILs) selectively and recyclably under hydrothermal conditions. The effects of reaction temperature, time, water amount and cellulose intake were investigated. Dilution effect becomes more pronounced at lower cellulose intake, dramatically improving the yield of LA to 86.1%. A kinetic model has been developed based on experimental data, whereby a good fit was obtained and kinetic parameters were derived. The relationships between IL structure, polymeric structure and depolymerization efficiency were established, shedding light on the in-depth catalytic mechanism of IL, inclusive of acidity and hydrogen bonding ability. The LA product can be readily separated through extraction by methyl isobutyl ketone (MIBK) and IL can be reused over five cycles without loss of activity. This environmentally friendly methodology can be applied to selective production of LA from versatile biomass feedstocks, including cellulose and derivatives, glucose, fructose and HMF.

  16. Biomimetic Fenton-catalyzed lignin depolymerization to high-value aromatics and dicarboxylic acids.

    Science.gov (United States)

    Zeng, Jijiao; Yoo, Chang Geun; Wang, Fei; Pan, Xuejun; Vermerris, Wilfred; Tong, Zhaohui

    2015-03-01

    By mimicking natural lignin degradation systems, the Fenton catalyst (Fe(3+), H2O2) can effectively facilitate lignin depolymerization in supercritical ethanol (7 MPa, 250 °C) to give organic oils that consist of mono- and oligomeric aromatics, phenols, dicarboxylic acids, and their derivatives in yields up to (66.0±8.5) %. The thermal properties, functional groups, and surface chemistry of lignin before and after Fenton treatment were examined by thermogravimetric analysis, pyrolysis-gas chromatography-mass spectrometry, (31)P NMR spectroscopy, and X-ray photoelectron spectroscopy. The results suggest that the Fenton catalyst facilitates lignin depolymerization through cleavage of β-ether bonds between lignin residues. The formation of a lignin-iron chelating complex effectively depresses lignin recondensation; thus minimizing charcoal formation and enhancing the yield of liquid products.

  17. Impact of the fouling mechanism on enzymatic depolymerization of xylan in different configurations of membrane reactors

    DEFF Research Database (Denmark)

    Mohd Sueb, Mohd Shafiq Bin; Luo, Jianquan; Meyer, Anne S.

    2017-01-01

    ) and the simultaneous reaction-filtration with both enzymes, respectively. This study thus confirmed that the reactor configuration has a crucial impact on the performance of both the reaction and the separation process of xylose during enzymatic xylan degradation, and that the type of fouling mechanism varies......In order to maximize enzymatic xylan depolymerization while simultaneously purifying the resulting monosaccharide (xylose), different ultrafiltration (UF) membrane reactor configurations were evaluated. Initial results showed that the two hydrolytic enzymes required for complete depolymerization...... of xylan, endo-1,4-β-xylanase and β-xylosidase, promoted different types of fouling, which had a direct impact on the extent of xylan hydrolysis achieved during reaction. Endo-1,4-β-xylanase generated DP 1-6 xylo-oligomers. These products contributed to partial pore blocking of the 1 kDa polysulfone...

  18. Effects of lignite application on ammonia and nitrous oxide emissions from cattle pens

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jianlei, E-mail: su@unimelb.edu.au [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia); Bai, Mei [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia); Shen, Jianlin [Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125 (China); Griffith, David W.T. [Department of Chemistry, University of Wollongong, NSW 2522 (Australia); Denmead, Owen T. [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia); Hill, Julian [Ternes Agricultural Consulting Pty Ltd, Upwey, VIC 3158 (Australia); Lam, Shu Kee; Mosier, Arvin R. [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia); Chen, Deli, E-mail: delichen@unimelb.edu.au [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia)

    2016-09-15

    Beef cattle feedlots are a major source of ammonia (NH{sub 3}) emissions from livestock industries. We investigated the effects of lignite surface applications on NH{sub 3} and nitrous oxide (N{sub 2}O) emissions from beef cattle feedlot pens. Two rates of lignite, 3 and 6 kg m{sup −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 NH{sub 3} and N{sub 2}O concentrations continuously from 4th Sep to 13th Nov 2014 using Quantum Cascade Laser (QCL) NH{sub 3} analysers and a closed-path Fourier Transform Infrared Spectroscopy analyser (CP-FTIR) in conjunction with the integrated horizontal flux method to calculate NH{sub 3} and N{sub 2}O fluxes. During the feeding period, 16 and 26% of the excreted nitrogen (N) (240 g N head{sup −1} day{sup −1}) was lost via NH{sub 3} volatilization from the control pen, while lignite application decreased NH{sub 3} volatilization to 12 and 18% of the excreted N, for Phase 1 and Phase 2, respectively. Compared to the control pen, lignite application decreased NH{sub 3} emissions by approximately 30%. Nitrous oxide emissions from the cattle pens were small, 0.10 and 0.14 g N{sub 2}O-N head{sup −1} day{sup −1} (< 0.1% of excreted N) for the control pen, for Phase 1 and Phase 2, respectively. Lignite application increased direct N{sub 2}O emissions by 40 and 57%, to 0.14 and 0.22 g N{sub 2}O-N head{sup −1} day{sup −1}, for Phase 1 and Phase 2, respectively. The increase in N{sub 2}O emissions resulting from lignite application was counteracted by the lower indirect N{sub 2}O emission due to decreased NH{sub 3} volatilization. Using 1% as a default emission factor of deposited NH{sub 3} for indirect N{sub 2}O emissions, the application of lignite decreased total N{sub 2}O emissions. - Graphical abstract: Lignite application substantially decreased NH{sub 3} emissions from cattle feedlots and increased

  19. A comparative study on the activity of fungal lytic polysaccharide monooxygenases for the depolymerization of cellulose in soybean spent flakes

    DEFF Research Database (Denmark)

    Pierce, Brian; Wittrup Agger, Jane; Zhang, Zhenghong

    2017-01-01

    Lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes capable of the oxidative breakdown of polysaccharides. They are of industrial interest due to their ability to enhance the enzymatic depolymerization of recalcitrant substrates by glycoside hydrolases. In this paper, twenty-...

  20. Chemical and physical properties of opencast lignite minesoils

    Energy Technology Data Exchange (ETDEWEB)

    Varela, C.; Vazquez, C.; Gonzalez-Sangregorio, M.V.; Leiros, M.C.; Gil-Sotres, F. (Facultad de Farmacia de Santiago de Compostela, Santiago de Compostela (Spain). Dept. de Edafologia y Quimica Agricola)

    1993-09-01

    The evolution of chemical and physical properties in a series of mine soils aged between 0 and 5 years, developed from spoil materials of the Meirama opencast lignite mine in Galicia (NW Spain), was studied. The soils are recovered without use of topsoil and are subject to identical management. In the surface horizon (0-7 cm), total C and N, CEC, and pyrophosphate-extracted Al[sub 2]O[sub 3] and Fe[sub 2]O[sub 3] increased with soil age. Oxalic-oxalate-extracted Al[sub 2]O[sub 3] and Fe[sub 2]O[sub 3] on the other hand, increased with soil age in all the horizons studied. Rapid recovery in terms of physical properties was also observed: bulk density dropped, while total porosity, percentage of macropores, and hydraulic conductivity increased, and aggregates showed greater stability on immersion in water. The results indicate that mineral weathering and organometallic complexation are the dominant processes at these early stages of edaphogenesis and that properties associated with gas exchange showed more rapid development than those associated with water movement. In spite of the above rapid modifications, the characteristics of the oldest soils in the series were still very different from those of native Galician soils.

  1. Workability and strength of lignite bottom ash geopolymer mortar.

    Science.gov (United States)

    Sathonsaowaphak, Apha; Chindaprasirt, Prinya; Pimraksa, Kedsarin

    2009-08-30

    In this paper, the waste lignite bottom ash from power station was used as a source material for making geopolymer. Sodium silicate and sodium hydroxide (NaOH) were used as liquid for the mixture and heat curing was used to activate the geopolymerization. The fineness of bottom ash, the liquid alkaline/ash ratio, the sodium silicate/NaOH ratio and the NaOH concentration were studied. The effects of the additions of water, NaOH and napthalene-based superplasticizer on the workability and strength of the geopolymer mortar were also studied. Relatively high strength geopolymer mortars of 24.0-58.0 MPa were obtained with the use of ground bottom ash with 3% retained on sieve no. 325 and mean particle size of 15.7 microm, using liquid alkaline/ash ratios of 0.429-0.709, the sodium silicate/NaOH ratios of 0.67-1.5 and 7.5-12.5M NaOH. The incorporation of water improved the workability of geopolymer mortar more effectively than the use of napthalene-based superplasticizer with similar slight reduction in strengths. The addition of NaOH solution slightly improves the workability of the mix while maintaining the strength of the geopolymer mortars.

  2. Maturity Control on the Patterns of Hydrocarbon Regeneration from Coal

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Rock-Eval pyrolysis and Py-GC experiments on naturally and artificially matured coal samples were carried out. The results suggest that both depolymerization and defuctionalization exist during the maturation and evolution of coal. The patterns of hydrocarbon regeneration are diverse at different stages of the maturation and evolution. When the vitrinite reflectance (R0) is 0.7%- 0.9%, bitumen is the richest in coal while activation energy is the minimum, and the temperature of peak yield is lower than that of primary hydrocarbon generation. However, if reflectance is greater than 0.9%, defunctionalization predominates and the temperature of peak regeneration is shown in lagging compared with the primary hydrocarbon generation. When reflectance is out of the "oil window", the peak temperature of hydrocarbon regeneration and that of the primary hydrocarbon generation seems to be continuous.

  3. Influence of wet oxidation on the surface area and the porosity of some lignites

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Karatepe, N.; Kucukbayrak, S. [Istanbul Technical University, Istanbul (Turkey). Chemical and Metallurgical Engineering Faculty

    2000-07-01

    Influence of wet oxidation on the surface area and the porosity of lignites was investigated using five different Turkish lignites. Lignite samples were oxidised in aqueous medium in a 1 l Parr autoclave at 423 K under 1.5 MPa partial pressure of oxygen for 60 min. Some physical properties such as surface area, bulk density, apparent density, mean pore radius, and porosity of the original and oxidised lignite samples were determined. For this purpose, BET and mercury intrusion porosimetry techniques were performed. In order to examine the effects of oxidation on the functional groups, FT-IR technique was applied for both original and oxidised lignite samples. On the other hand, some inorganic constituents were eliminated from the samples as a result of in situ formation of sulphuric acid from oxidation of sulphur compounds. The changes taken place in the physical properties were studied considering chemical compositions of the samples and the extent of the interaction between the samples and oxygen. 6 refs., 3 figs., 5 tabs.

  4. Evolvement behavior of microstructure and H2O adsorption of lignite pyrolysis☆

    Institute of Scientific and Technical Information of China (English)

    Yingyue Teng; Shijun Lian; Quansheng Liu⁎; Yuzhe Liu; Yinmin Song; Runxia He; Keduan Zhi

    2016-01-01

    The effect of pyrolysis on the microstructure and moisture adsorption of lignite was investigated with low field nuclear magnetic resonance spectroscopy. Changes in oxygen-containing groups were analyzed by Fourier transform infrared spectroscopy (FTIR), and H2O adsorption mechanism on the surface of lignite pyrolysis was inferred. Two major changes in the pore structure of lignite char were observed as temperature increased in 105–200 °C and 500–700 °C. Pyrolysis temperature is a significant factor in removing carboxyl and phenolic hydroxyl from lignite. Variation of ether bond content can be divided into three stages;the content initially increased, then decreased, and final y increased. The equilibrium adsorption ratio, content of oxygen-containing groups, and variation of pore volume below 700° were closely correlated with each other. The amount of adsorbed water on char pyrolyzed at 700 °C increased. Moreover, the adsorption capacity of the lignite decreased, and the adsorption state changed.

  5. Conversion of Low-Rank Wyoming Coals into Gasoline by Direct Liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Polyakov, Oleg

    2013-12-31

    Under the cooperative agreement program of DOE and funding from Wyoming State’s Clean Coal Task Force, Western Research Institute and Thermosolv LLC studied the direct conversion of Wyoming coals and coal-lignin mixed feeds into liquid fuels in conditions highly relevant to practice. During the Phase I, catalytic direct liquefaction of sub-bituminous Wyoming coals was investigated. The process conditions and catalysts were identified that lead to a significant increase of desirable oil fraction in the products. The Phase II work focused on systematic study of solvothermal depolymerization (STD) and direct liquefaction (DCL) of carbonaceous feedstocks. The effect of the reaction conditions (the nature of solvent, solvent/lignin ratio, temperature, pressure, heating rate, and residence time) on STD was investigated. The effect of a number of various additives (including lignin, model lignin compounds, lignin-derivable chemicals, and inorganic radical initiators), solvents, and catalysts on DCL has been studied. Although a significant progress has been achieved in developing solvothermal depolymerization, the side reactions – formation of considerable amounts of char and gaseous products – as well as other drawbacks do not render aqueous media as the most appropriate choice for commercial implementation of STD for processing coals and lignins. The trends and effects discovered in DCL point at the specific features of liquefaction mechanism that are currently underutilized yet could be exploited to intensify the process. A judicious choice of catalysts, solvents, and additives might enable practical and economically efficient direct conversion of Wyoming coals into liquid fuels.

  6. Peroxynitrite induces F-actin depolymerization and blockade of myosin ATPase stimulation.

    Science.gov (United States)

    Tiago, Teresa; Ramos, Susana; Aureliano, Manuel; Gutiérrez-Merino, Carlos

    2006-03-31

    Treatment of F-actin with the peroxynitrite-releasing agent 3-morpholinosydnonimine (SIN-1) produced a dose-dependent F-actin depolymerization. This is due to released peroxynitrite because it is not produced by 'decomposed SIN-1', and it is prevented by superoxide dismutase concentrations efficiently preventing peroxynitrite formation. F-actin depolymerization has been found to be very sensitive to peroxynitrite, as exposure to fluxes as low as 50-100nM peroxynitrite leads to nearly 50% depolymerization in about 1h. G-actin polymerization is also impaired by peroxynitrite although with nearly 2-fold lower sensitivity. Exposure of F-actin to submicromolar fluxes of peroxynitrite produced cysteine oxidation and also a blockade of the ability of actin to stimulate myosin ATPase activity. Our results suggest that an imbalance of the F-actin/G-actin equilibrium can account for the observed structural and functional impairment of myofibrils under the peroxynitrite-mediated oxidative stress reported for some pathophysiological conditions.

  7. Improved postharvest quality in patagonian squash (Cucurbita moschata) coated with radiation depolymerized chitosan

    Energy Technology Data Exchange (ETDEWEB)

    Pugliese, Maria Alicia; Goitia, Maria Teresa [Laboratorio de Investigaciones Basicas Aplicadas en Quitina, Departamento de Quimica, Universidad Nacional del Sur. Avenida Alem 1253, B8000CPB Bahia Blanca (Argentina); Yossen, Mariana [Instituto de Desarrollo Tecnologico para la Industria Quimica (INTEC), CONICET-Universidad Nacional del Litoral, Ruta Nacional 168-Paraje ' El Pozo' , 3000 Santa Fe (Argentina); Cifone, Norma; Agullo, Enrique [Laboratorio de Investigaciones Basicas Aplicadas en Quitina, Departamento de Quimica, Universidad Nacional del Sur. Avenida Alem 1253, B8000CPB Bahia Blanca (Argentina); Andreucetti, Noemi, E-mail: andreuce@criba.edu.ar [Laboratorio de Radioisotopos, Departamento de Quimica, Universidad Nacional del Sur, Avenida Alem 1253, B8000CPB Bahia Blanca (Argentina)

    2011-12-15

    Different molecular weight chitosans were evaluated on the decay of coated Anquito squashes (Cucurbita moschata) as well as the maintenance of the fruit quality along five storage months. The original chitosan (Mw=391 kDa, 83% DD), was depolymerized by gamma radiation. Apart from chain scission, other chemical changes were not detected by FTIR or UV-vis analyses. The molecular weight characterization of chitosans was done by size exclusion chromatography with dual light scattering and concentration detection (SEC-MALLS-RI). The coating effectiveness was evaluated on the following parameters: fungal decay incidence, weight loss, firmness, total reducing sugar, soluble solid, flesh color, carotene content, pH and titratable acidity. No sign of fungal decay was observed in squashes coated with 122 and 56 kDa chitosans, which were also the most effective treatments in reducing the weight loss. The chitosan with Mw=122 kDa was also the best treatment considering firmness, internal aspect, sugar and carotene content. Then, radiation degraded chitosan was better in C. moschata preservation than the original chitosan. - Highlights: > Original Chitosan was radiation depolymerized producing chitosans with lower molecular weights. > Gamma-irradiated chitosans only exhibit chain scission. > SEC-MALLS-RI chromatography is a useful tool in molecular weight analysis. > Depolymerized chitosans were the best in maintaining the quality and the storage life of coated squashes.

  8. Fermentation Process of Cocoa Based on Optimum Condition of Pulp PectinDepolymerization by Endogenous Pectolityc Enzymes

    Directory of Open Access Journals (Sweden)

    G.P. Ganda-Putra

    2010-08-01

    Full Text Available Pulp degradation during cocoa fermentation can be carried out by depolymerization process of pulp pectin using endogenous pectolytic enzymes at optimum condition. The objectives of this research were to study the effect of fermentation process based on optimum condition in terms of temperature and pH of pulp pectin depolymerization using endogenous pectolytic enzymes polygalakturonase (PG and pectin metyl esterase (PME and fermentation period in cocoa processing on quality characteristics of cocoa beans produced and to study the role of those fermentation process in reducing fermentation time to produce cocoa beans with standard quality. This research used split plot design, with treatments of process condition of cocoa fermentation as main plot and fermentation period as split plot. Treatment of process condition of cocoa fermentation consisted of optimum condition for pulp pectin depolymerization by PGs (temperature 47.5OC; initial pulp pH 4.6; optimum condition of depolymerization on sequence depolymerization by PGs (temperature 48.5OC; initial pulp pH 8.0 during 1 day; last temperature 47.5OC; initial pulp pH 4.6 during 6 days, and natural fermentation process a control. While treatment of fermentation period consisted of 0, 1, 2, 3, 4, 5, 6 and 7 days. Evaluation of fermentation period was carried out based on pursuant to criteria of unfermented beans content and fermentation index. The results showed that process condition and fermentation time of cocoa affected quality characteristic of cocoa beans produced. Period of cocoa fermentation process based on optimum condition for pulp pectin depolymerization using endogenous pectolytic enzymes was 2 days shorter compared to natural fermentation. Cocoa beans quality of grade I and II were obtained from fermentation time of 4 and 2 days, respectively, using fermentation process based on optimum condition of pulp pectin depolymerization using endogenous pectolytic enzymes, whereas 6 and 4 days

  9. 互花米草与褐煤共热解特性试验%Experiment on co-pyrolysis characteristics of Spartina alterniflora and lignite

    Institute of Scientific and Technical Information of China (English)

    李继红; 杨世关; 李晓彤

    2014-01-01

    Smooth cordgrass (Spartina alterniflora), a saltmarsh plant, has spread in intertidal flats of many regions of China since it was introduced from the USA in 1979. The application of S. alternilfora in energy has gained more attention due to its high production. However, the direct combustion of S. alternilfora was hindered due to its high potassium (K) and sodium (Na) contents. Co-pyrolysis of biomass and coal, a subject of much study in an effort to reduce greenhouse gases emission, was reported to be able to produce a synergetic effect mainly due to the catalytic function of alkali metals in biomass. S. alterniflora, rich in Na and K which are 22 683 mg/kg and 8 063 mg/kg, respectively, has great bioenergy potential as a co-pyrolysis material of coal. In order to to verify the interaction of S. alterniflora and lignite during pyrolysis, experiments were carried out with pure S. alterniflora, pure lignite, and their blends with mass ratio (S. alterniflora to lignite, S:L) of 1:4, 2:3, 3:2, and 4:1 by thermogravimetry coupled with a Fourier transform infrared spectroscopy (TG-FTIR). S. alternilfora used in the experiments was collected from Dafeng County of Jiangsu Province, China in October 2012. Lignite was from Shanxi Province, China. Na, K, volatile, H/C, O/C, and heating value of S. alterniflora were 16 064.3 mg/kg, 6 175.7 mg/kg, 75.40%, 0.12, 0.80, and 19.08 MJ/kg, respectively. Volatile content, H/C, O/C, and heating value of lignite were 33.92%, 0.07, 0.23, and 20.47 MJ/kg, respectively. TG tests were done under an N2 flow rate of 25 mL/min and at a heating rate of 10℃/min from 30℃ to 900℃. Infrared scanning resolution was set to 4cm-1, and scanning scope varied from 4 000 cm-1 to 500 cm-1. According to TG and DTG analysis, the process of co-pyrolysis can be divided into two stages at 385℃. The pyrolysis of S. alterniflora took place mainly in the first stage of 250℃ to 385℃. The pyrolysis of lignite and fixed carbon in S. alterniflora occurred

  10. Coal liquefaction technology. (Latest citations from the NTIS Bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    The bibliography contains citations concerning the technologies and processes for converting coal to liquid chemicals and fuels. Topics include materials characterization of liquefaction processes, catalysis, pyrolysis, depolymerization, coprocessing, and integrated liquefaction. Also discussed are liquid fuel use in automobiles and power generation, low-temperature carbonization technology, multi-stage liquefaction, cost benefit analysis, and commercialization of liquefaction technology. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  11. Maturation-related changes in the distribution of ester-bound fatty acids and alcohols in a coal series from the New Zealand Coal Band covering diagenetic to catagenetic coalification levels

    DEFF Research Database (Denmark)

    Glombitza, Clemens; Mangelsdorf, Kai; Horsfield, Brian

    2009-01-01

    A rank series of lignites and coals of low to moderate maturation levels (vitrinite reflectance (R0): 0.27–0.8%) from the New Zealand Coal Band were investigated using alkaline ester cleavage experiments to reveal compositional changes of ester bound components (fatty acids and alcohols) during...... increasing maturation. Ester bound alcohols are found to be present in highest amounts in the very immature lignite samples (R0: 0.27–0.29%), but show a rapid decrease during early diagenesis. Ester bound fatty acids also show an initial exponential decrease during diagenesis, but reveal an intermittent...... containing C16 and C18 fatty acids as main cell membrane components. Deep microbial life might be stimulated at this interval by the increasing release of thermally generated potential substrates from the organic matrix during early catagenesis. In contrast to the fatty acids, the high amounts of alcohols...

  12. Advanced liquefaction using coal swelling and catalyst dispersion techniques. Quarterly technical progress report No. 7, April 1993--June 1993

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, C.W. [Auburn Univ., AL (United States); Chander, S. [Pennsylvania State Univ., University Park, PA (United States); Gutterman, C.

    1994-09-01

    The overall objective of this project is to develop a new approach for the direct liquefaction of coal to produce an all-distillate product slate at a sizable cost reduction over current technology. The approach integrates coal selection, pretreatment, coal swelling with catalyst impregnation, liquefaction, product recovery with characterization, alternate bottoms processing, and carrying out a technical assessment including an economic evaluation. The project is being carried out under contract to the United States Department of Energy. All three coals used in this study (Black Thunder, Burning Star bituminous, and Martin Lake lignite) are effectively swelled by a number of solvents. The most effective solvents are those having hetero-functionality. In addition, a synergistic effect has been demonstrated, in which solvent blends are more effective for coal swelling than the pure solvents alone. Therefore, it will be necessary to use only low levels of swelling agents and yet promote the impregnation of catalyst precursors. The rate of the impregnation of catalyst precursors into swollen coal increases greatly as the effectiveness of the solvent to swell the coal increases. This effect is also demonstrated by improved catalyst precursor impregnation with increased contact temperature. Laboratory- and bench-scale liquefaction experimentation is underway using swelled and catalyst impregnated coal samples. Higher coal conversions were observed for the SO{sub 2}-treated coal than the raw coal, regardless of catalyst type. Conversions of swelled coal were highest when Molyvan-L, molybdenum naphthenate, and nickel octoate, respectively, were added to the liquefaction solvent.

  13. Microbial and chemical factors influencing methane production in laboratory incubations of low-rank subsurface coals

    Science.gov (United States)

    Harris, Stephen H.; Smith, Richard L.; Barker, Charles E.

    2008-01-01

    Lignite and subbituminous coals were investigated for their ability to support microbial methane production in laboratory incubations. Results show that naturally-occurring microorganisms associated with the coals produced substantial quantities of methane, although the factors influencing this process were variable among different samples tested. Methanogenic microbes in two coals from the Powder River Basin, Wyoming, USA, produced 140.5-374.6 mL CH4/kg ((4.5-12.0 standard cubic feet (scf)/ton) in response to an amendment of H2/CO2. The addition of high concentrations (5-10 mM) of acetate did not support substantive methane production under the laboratory conditions. However, acetate accumulated in control incubations where methanogenesis was inhibited, indicating that acetate was produced and consumed during the course of methane production. Acetogenesis from H2/CO2 was evident in these incubations and may serve as a competing metabolic mode influencing the cumulative amount of methane produced in coal. Two low-rank (lignite A) coals from Fort Yukon, Alaska, USA, demonstrated a comparable level of methane production (131.1-284.0 mL CH4/kg (4.2-9.1 scf/ton)) in the presence of an inorganic nutrient amendment, indicating that the source of energy and organic carbon was derived from the coal. The concentration of chloroform-extractable organic matter varied by almost three orders of magnitude among all the coals tested, and appeared to be related to methane production potential. These results indicate that substrate availability within the coal matrix and competition between different groups of microorganisms are two factors that may exert a profound influence on methanogenesis in subsurface coal beds.

  14. FT-IR and XRD analysis of coal from Makum coalfield of Assam

    Indian Academy of Sciences (India)

    Binoy K Saikia; R K Boruah; P K Gogoi

    2007-12-01

    High sulphur coal sample from Ledo colliery of Makum coalfield, Assam, India was studied using FT-IR and XRD methods. FT-IR study shows the presence of aliphatic –CH, –CH2 and –CH3 groups, aliphatic C–O–C stretching associated with –OH and –NH stretching vibrations and HCC rocking (single and condensed rings). XRD pattern of the coal shows that it is amorphous in nature. Function of Radial Distribution Analysis (FRDA) indicates that coal is lignite in type and there is no evidence of graphite-like structure. The first maximum in the G() plot of FRDA at = 0.14 nm relates to the aliphatic C–C bond (Type C–CH=CH–C), the second maximum at = 0.25 nm relates to the distance between carbon atoms of aliphatic chains that are located across one carbon atom. The curve intensity profiles obtained from FRDA show quite regular molecular packets for this coal. The coal was found to be lignite in nature.

  15. Impact of coal structural heterogeneity on the nonideal sorption of organic contaminants.

    Science.gov (United States)

    Shi, Xin; Fu, Heyun; Li, Yuan; Mao, Jingdong; Zheng, Shourong; Zhu, Dongqiang

    2011-06-01

    Carbonaceous geosorbents (black carbon, coal, and humin/kerogen) play a primary role in the nonideal sorption (isotherm nonlinearity, hysteresis, and multiphasic kinetics) of hydrophobic organic chemicals by soils and sediments. The present study investigated the impact of coal structural heterogeneity on sorption/desorption of two model monoaromatic compounds (1,3-dichlorobenzene and 1,3-dinitrobenzene). Due to the higher degree of aromaticity and condensation, anthracite showed stronger sorption affinity and nonlinearity and slower sorption kinetics than lignite. Removal of humic substances by alkali extraction and/or mineral fraction by acidification did not much affect organic carbon-normalized sorption coefficient to the coal, suggesting nearly complete accessibility of adsorption sites on the condensed organic carbon. However, the treatments greatly increased sorption kinetics and meanwhile alleviated hysteresis of 1,3-dinitrobenzene, as compared with the original lignite. These observations were attributed to the enhanced exposure of high-energy adsorption sites on the condensed organic carbon after exfoliating the surface coverage by humic substances and minerals. An empirical biphasic pseudo-second-order model consisting of a fast sorption phase and a slow sorption phase adequately quantified the overall sorption kinetics for the coal sorbents. The results indicated that the condensed organic carbon, in combination with other structural components, controls the nonideal sorption of unburned coal. Copyright © 2011 SETAC.

  16. Comparative study of semi-industrial-scale flames of pulverized coals and biomass

    Energy Technology Data Exchange (ETDEWEB)

    Ballester, J.; Barroso, J.; Cerecedo, L.M.; Ichaso, R. [University of Zaragoza, Zaragoza (Spain)

    2005-05-01

    Three p.f. flames have been studied in a semi-industrial furnace, using different fuels: a bituminous coal, a lignite, and a biomass (oak sawdust). The operating conditions were exactly the same for the two coals, and very similar to those for the biornass flame. The objective was to evaluate the impact of differences in fuel composition on flame characteristics, through measurement of the spatial distribution of the main parameters: temperature and concentrations of O{sub 2}, CO, NOx, unburnt hydrocarbons, and N{sub 2}O. The higher volatiles content in the lignite leads to higher temperatures and more intense combustion than the bituminous coal. Nevertheless, as might be expected, more marked differences are observed between the flames from the biomass and coals. The much higher volatiles content of the wood results in a more intense flame close to the burner, as indicated by visual observations and by concentrations of unburnt gases (CO and unburnt hydrocarbons) in that zone. It is remarkable that the combustion zone extends further for the biomass; while unburnt species were very low for the coals at an axial distance of 1 m, high values were detected for the pulverized oak. The measurements suggest that two stages can be distinguished in the biomass flame: a zone of intense combustion close to the burner, followed by a second region where the large biomass particles gradually devolatilize and are consumed.

  17. FT-IR and XRD analysis of coal from Makum coalfield of Assam

    Energy Technology Data Exchange (ETDEWEB)

    Saikia, B.K.; Boruah, R.K.; Gogoi, P.K. [Tezpur University, Tezpur (India). Dept. of Chemical Science

    2007-12-15

    High sulphur coal sample from Ledo colliery of Makum coalfield, Assam, India was studied using FT-IR and XRD methods. FT-IR study shows the presence of aliphatic -CH, -CH{sub 2} and -CH{sub 3} groups, aliphatic C-O-C stretching associated with -OH and -NH stretching vibrations and HCC rocking (single and condensed rings). XRD pattern of the coal shows that it is amorphous in nature. Function of Radial Distribution Analysis (FRDA) indicates that coal is lignite in type and there is no evidence of graphite-like structure. The first maximum in the G(r) plot of FRDA at r = 0.14 nm relates to the aliphatic C-C bond (Type C-CH = CH-C), the second maximum at r = 0.25 nm relates to the distance between carbon atoms of aliphatic chains that are located across one carbon atom. The curve intensity profiles obtained from FRDA show quite regular molecular packets for this coal. The coal was found to be lignite in nature.

  18. COAL GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>20141574 Chen Hao(Exploration and Development Research Institute,Daqing Oilfield Company,Daqing 163712,China)High-Resolution Sequences and Coal Accumulating Laws in Nantun Formation of Huhe Lake Sag(Petroleum Geology&Oilfield Development in Daqing,ISSN1000-3754,CN23-1286/TQ,32(4),2013,p.15-19,5 illus.,15 refs.)Key words:coal accumulation regularity,coal

  19. COAL GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>20091159 Gao Yan(No.3 Prospecting Team of Anhui Bureau of Coal Geology,Suzhou 234000,China) Effect of Depositional Environment of Coal-Bearing Stratum on Major Coal Seams in Suntan Coalmine,Anhui Province(Geology of Anhui,ISSN 1005- 6157,CN34-1111/P,18(2),2008,p.114 -117,5 illus.,1 ref.,with English abstract)

  20. Technical and Sociological Investigation of Impacts in Using Lignite Mine Drainage for Irrigation - A Case Study

    Science.gov (United States)

    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

  1. Determination of optimal environmental policy for reclamation of land unearthed in lignite mines - Strategy and tactics

    Science.gov (United States)

    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.

  2. Thermogravimetric investigation of the co-combustion between the pyrolysis oil distillation residue and lignite.

    Science.gov (United States)

    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.

  3. Influence of litter chemistry and stoichiometry on glucan depolymerization during decomposition of beech (Fagus sylvatica L.) litter.

    Science.gov (United States)

    Leitner, Sonja; Wanek, Wolfgang; Wild, Birgit; Haemmerle, Ieda; Kohl, Lukas; Keiblinger, Katharina M; Zechmeister-Boltenstern, Sophie; Richter, Andreas

    2012-07-01

    Glucans like cellulose and starch are a major source of carbon for decomposer food webs, especially during early- and intermediate-stages of decomposition. Litter quality has previously been suggested to notably influence decomposition processes as it determines the decomposability of organic material and the nutrient availability to the decomposer community. To study the impact of chemical and elemental composition of resources on glucan decomposition, a laboratory experiment was carried out using beech (Fagus sylvatica, L.) litter from four different locations in Austria, differing in composition (concentration of starch, cellulose and acid unhydrolyzable residue or AUR fraction) and elemental stoichiometry (C:N:P ratio). Leaf litter was incubated in mesocosms for six months in the laboratory under controlled conditions. To investigate the process of glucan decomposition and its controls, we developed an isotope pool dilution (IPD) assay using (13)C-glucose to label the pool of free glucose in the litter, and subsequently measured the dilution of label over time. This enabled us to calculate gross rates of glucose production through glucan depolymerization, and glucose consumption by the microbial community. In addition, potential activities of extracellular cellulases and ligninases (peroxidases and phenoloxidases) were measured to identify effects of resource chemistry and stoichiometry on microbial enzyme production. Gross rates of glucan depolymerization and glucose consumption were highly correlated, indicating that both processes are co-regulated and intrinsically linked by the microbial demand for C and energy and thereby to resource allocation to enzymes that depolymerize glucans. At early stages of decomposition, glucan depolymerization rates were correlated with starch content, indicating that starch was the primary source for glucose. With progressing litter decomposition, the correlation with starch diminished and glucan depolymerization rates were

  4. Comparative radiocarbon dating of lignite, pottery, and charcoal samples from Babeldaob Island, Republic of Palau

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, A.; Chappell, J.; Clark, G.; Phear, S. [Australian National University, Canberra, ACT (Australia)

    2005-07-01

    It is difficult to construct archaeological chronologies for Babeldaob, the main island of Palau (western Micronesia), because the saprolitic clays of the dominant terraced-hill sites and associated ceramic sherds often contain old carbon that originated in lignites. This has implications, as well, for chronologies of sedimentary sequences. Comparative analysis of the dating problem using lignite, pottery, and charcoal samples indicates that, in fact, there are both old and young sources of potential contamination. It is concluded that radiocarbon samples from Babeldaob need to be tested for appropriate carbon content rather than relying solely upon material identification.

  5. A statistical study of equipment operating time in an open pit lignite mine

    Energy Technology Data Exchange (ETDEWEB)

    Xerokostas, D.; Polyzos, P.; Galitis, N.; Michiotis, A.; Dalakas, G. (National Technical University, Athens (Greece). Dept. of Mechanical Engineering)

    1991-08-01

    The production planning of an open pit lignite mine, as of any mining operation in general, is influenced by a series of factors. Of great importance among these factors is the operating time of the equipment used in the production process. In this paper the authors use applied statistical methods (specially comparison tests) to study the net operating time of some excavation branches of the Ptolemais lignite mining district in Greece. Thus, it is hoped that the paper will contribute to estimating and predicting equipment performance in a more accurate way. 4 refs., 4 figs., 3 tabs.

  6. Co-pyrolysis of Chinese lignite and biomass in a vacuum reactor.

    Science.gov (United States)

    Yang, Xiao; Yuan, Chengyong; Xu, Jiao; Zhang, Weijiang

    2014-12-01

    A vacuum fixed bed reactor was applied to pyrolyze lignite, biomass (rice husk) and their blend with high temperature (900 °C) and low heating rate (10 °C/min). Pyrolytic products were kept in the vacuum reactor during the whole pyrolysis process, guaranteeing a long contact time (more than 2 h) for their interactions. Remarkable synergetic effects were observed. Addition of biomass obviously influenced the tar and char yields, gas volume yield, gas composition, char structure and tar composition during co-pyrolysis. It was highly possible that char gasification, gaseous phase interactions, and secondary tar cracking were facilitated when lignite and biomass were co-pyrolyzed.

  7. Preparation and combustion of coal-water fuel from the Sin Pun coal deposit, southern Thailand

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    In response to an inquiry by the Department of Mineral Resources in Thailand, the Energy & Environmental Research Center (EERC) prepared a program to assess the responsiveness of Sin Pun lignite to the temperature and pressure conditions of hot-water drying. The results indicate that drying made several improvements in the coal, notably increases in heating value and carbon content and reductions in equilibrium moisture and oxygen content. The equilibrium moisture content decreased from 27 wt% for the raw coal to about 15 wt% for the hot-water-dried (HWD) coals. The energy density for a pumpable coal-water fuel (CWF) indicates an increase from 4500 to 6100 Btu/lb by hot-water drying. Approximately 650 lb of HWD Sin Pun CWF were fired in the EERC`s combustion test facility. The fuel burned extremely well, with no feed problems noted during the course of the test. Fouling and slagging deposits each indicated a very low rate of ash deposition, with only a dusty layer formed on the cooled metal surfaces. The combustor was operated at between 20% and 25% excess air, resulting in a flue gas SO{sub 2} concentration averaging approximately 6500 parts per million.

  8. Cooperative research in coal liquefaction. Final report, May 1, 1992--April 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Huffman, G.P. [ed.

    1996-03-01

    Research on sulfate and metal (Mo, Sn) promoted Fe{sub 2}O{sub 3} catalysts in the current year focused on optimization of conditions. Parameters varied included temperature, solvent, solvent-to-coal ratio, and the effect of presulfiding versus in situ sulfiding. Oil yields were found to increase approximately proportionately with both temperature and solvent-to-coal ratio. The donor solvent, tetralin, proved to give better total conversion and oil yields than either 1-methylnaphthalene or Wilsonville recycle oil. A significant enhancement of both total liquefaction yields and oil yields from lignites and subbituminous coals has been achieved by incorporating iron into the coal matrix by cation exchange. A study has been conducted on the synthesis of iron, molybdenum, and tungsten catalysts using a laser pyrolysis technique.

  9. Low-rank coal study: national needs for resource development. Volume 3. Technology evaluation

    Energy Technology Data Exchange (ETDEWEB)

    1980-11-01

    Technologies applicable to the development and use of low-rank coals are analyzed in order to identify specific needs for research, development, and demonstration (RD and D). Major sections of the report address the following technologies: extraction; transportation; preparation, handling and storage; conventional combustion and environmental control technology; gasification; liquefaction; and pyrolysis. Each of these sections contains an introduction and summary of the key issues with regard to subbituminous coal and lignite; description of all relevant technology, both existing and under development; a description of related environmental control technology; an evaluation of the effects of low-rank coal properties on the technology; and summaries of current commercial status of the technology and/or current RD and D projects relevant to low-rank coals.

  10. Rheological behavior of Shengli coal-solvent slurry at low-temperatures and atmospheric pressure

    Institute of Scientific and Technical Information of China (English)

    WANG Yong-gang; YAN Yan; GUO Xiang-kun; Xu De-ping

    2009-01-01

    We report the results from systematic studies of Shengli lignite coal-solvent slurries. Solvent type, temperature, coal to solvent ratio, particle granularity, shear rate and shear time were investigated. The viscosity of the solvents is time independent. However, the slurries are thixotropic. A change from pseudo-plastic to Newtonian behavior occurs as the temperature, or as the solvent to coal ratio, increases. The solvent used in the slurry affects the point at which the theology changes from pseudo-plastic to Newtonian. The REC slurry changes at 1 : 1.2 coal to solvent ratio and at 40 ℃. The HAR slurry changes at a 1:1.5 ratio and at 60 ℃. The theology of the slurries is pseudo-plastic at low shear rates but Newtonian at high shear rates.

  11. Integral management system for production in open-cast coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Arias, M.A.A.; Garcia-Sineriz M, J.L. [Lignitos de Meirama, S.A., Meirama (Spain)

    1993-12-31

    In 1991, 9.5 million m{sup 3} of material from a Spanish open-cast brown coal mine were transported by a belt conveyor system to a coal depot or a waste heap. Development of an integral management system to automate the conveyor belt circuits for transport of the lignite and clayish material extracted by three excavators and the rock from two semi-mobile crushers is described. The material is carried to a distribution point and tipped onto three collector circuits for coal and waste. The system saturates the capacity of the conveyor belt circuits for coal and waste without causing overloading or holdup. The control system acts on allocated set-points of the production machines. The system does not require weighers or density sensors in the belts to continuously estimate the density of the material being transported. 5 refs., 5 figs.

  12. COAL GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>20131668 Chang Huizhen(Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process,CUMT,Ministry of Edu-cation,School of Resource and Earth Science,China University of Mining and Technology,Xuzhou 221008,China);Qin Yong Differences in of Pore Structure of Coals and Their Impact on the Permeability of Coals from the

  13. A kinetic study of gaseous potassium capture by coal minerals in a high temperature fixed-bed reactor

    DEFF Research Database (Denmark)

    Zheng, Yuanjing; Jensen, Peter Arendt; Jensen, Anker Degn

    2008-01-01

    The reactions between gaseous potassium chloride and coal minerals were investigated in a lab-scale high temperature fixed-bed reactor using single sorbent pellets. The applied coal minerals included kaolin, mullite, silica, alumina, bituminous coal ash, and lignite coal ash that were formed...... into long cylindrical pellets. Kaolin and bituminous coal ash that both have significant amounts of Si and Al show superior potassium capture characteristics. Experimental results show that capture of potassium by kaolin is independent of the gas oxygen content. Kaolin releases water and forms metakaolin...... at temperatures below 1300°C. However, the weight gain by mullite is only slightly smaller than that by kaolin in the temperature range of 1300-1500°C. A simple model was developed for the gas-solid reaction between potassium vapor and metakaolin pellet at 900°C....

  14. Evaluation of ash deposits during experimental investigation of co-firing of Bosnian coal with wooden biomass

    Energy Technology Data Exchange (ETDEWEB)

    Smajevic, Izet; Kazagic, Anes [JP Elektroprivreda BiH d.d., Sarajevo (Bosnia and Herzegovina); Sarajevo Univ. (Bosnia and Herzegovina). Faculty of Mechanical Engineering

    2008-07-01

    The paper is addressed to the development and use different criteria for evaluation of ash deposits collected during experimental co-firing of Bosnian coals with wooden biomass. Spruce saw dust was used for the co-firing tests with the Kakanj brown coal and with a lignite blend consisted of the Dubrave lignite and the Sikulje lignite. The coal/biomass mixtures at 93:7 %w and at 80:20 %w were tested. Experimental lab-scale facility PF entrained flow reactor is used for the co-firing tests. The reactor allows examination of fouling/slagging behaviors and emissions at various and infinitely variable process temperature which can be set at will in the range from ambient to 1560 C. Ash deposits are collected on two non-cooled ceramic probes and one water-cooled metal surface. Six different criteria are developed and used to evaluate behavior of the ash deposits on the probes: ash deposit shape, state and structure, which are analyzed visually - photographically and optically by a microscope, rate of adhesion and ash deposit strength, analyzed by physic acting to the ash deposits, and finally deposition rate, determined as a mass of the deposit divided by the collecting area and the time of collecting. Furthermore, chemical composition analysis and AFT of the ash deposits were also done to provide additional information on the deposits. (orig.)

  15. Pore structure development of in-situ pyrolyzed coals for pollution prevention in iron foundries

    Energy Technology Data Exchange (ETDEWEB)

    Huang, He; Cannon, Fred S. [Department of Civil and Environmental Engineering, The Pennsylvania State University, 212 Sackett Building, University Park, PA 16802 (United States); Wang, Yujue [Department of Environmental Science and Engineering, Tsinghua University, Bejing, 100084 (China)

    2009-09-15

    A protocol was devised for preparing pyrolyzed coals that could be made in-situ at foundries to capture volatile organic compound (VOC) emission. This pyrolysis created extensive micropore volume in lignite over a broad range of temperature and time; and could use waste heat from cupola exhaust gases by a heat-exchange tube. For foundry application, moderate porous carbon with relatively uniform pores over wide ranges of temperature and time would be more practical than highly porous activated carbon (AC) that requires narrowly-controlled operations. This pyrolysis protocol was developed in a thermogravimetric analyzer (TGA) and in a small tube furnace, while using lignite, bituminous coal, and anthracite. The lignite yielded the most pore volume; and this was relatively uniform (0.1-0.13 mL/g of pores) while temperatures were 600-900 C, and times were 0-60 min. Smaller grain sizes yielded improved porosity; and this corresponded to more release of phenols and naphthalenes from smaller grains, as discerned by TGA-mass spectroscopy (MS). TGA-MS also revealed that improved pore development between 600-800 C corresponded to the release of CO{sub 2} and H{sub 2}O; and concurrently higher slurry pH linked to less oxygenated functionality. Adsorption of benzene was compared between the in-situ porous carbon and a commercial AC. (author)

  16. Coal combustion products: trash or treasure?

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, T.

    2006-07-15

    Coal combustion by-products can be a valuable resource to various industries. The American Coal Ash Association (ACAA) collects data on production and uses of coal combustion products (CCPs). 122.5 million tons of CCPs were produced in 2004. The article discusses the results of the ACCA's 2004 survey. Fly ash is predominantly used as a substitute for Portland cement; bottom ash for structural fill, embankments and paved road cases. Synthetic gypsum from the FGD process is commonly used in wallboard. Plant owners are only likely to have a buyer for a portion of their CCPs. Although sale of hot water (from Antelope Valley Station) from condensers for use in a fish farm to raise tilapia proved unviable, the Great Plains Synfuels Plant which manufactures natural gas from lignite produces a wide range of products including anhydrous ammonia, phenol, krypton, carbon dioxide (for enhanced oil recovery), tar oils and liquid nitrogen. ACCA's goal is to educate people about CCPs and how to make them into useful products, and market them, in order to reduce waste disposal and enhance revenue. The article lists members of the ACCA. 2 photos., 1 tab.

  17. The German coal market in 2011; Der deutsche Steinkohlenmarkt im Jahr 2011

    Energy Technology Data Exchange (ETDEWEB)

    Loo, Kai van de; Luebke, Roland; Boergel, Thomas [Gesamtverband Steinkohle e.V. (GVSt), Herne (Germany); Verschuur, Michael [Statistik der Kohlenwirtschaft e.V., Herne (Germany)

    2012-07-01

    Compared to the previous year the German coal market recorded a slight fall in total consumption by 0.7% to 57.5 mill. coal units. Whereas coking coal and coke consumption of the steel industry clearly increased (+4.3%) due to the boom, sale of power station coals declined considerably in 2011 (-2.5%). However, electricity generation in Germany fell by almost the same amount (-2.2%). Primary energy consumption even declined by a good 5% to its lowest level since 1990 - probably because of the mild weather - and this despite economic growth of 3% in 2011. It must be stated that there was no increase in generation of electricity from bituminous coal following shutdown of eight of the 17 German nuclear power stations in the wake of the events at Fukushima although this was not the case with renewable energy and lignite. The political decisions in 2011 to expedite the energy turning point in Germany also do not suggest a continuous upward trend in the future. Bituminous coal occupied third place in the national energy mix in 2011 both in primary energy consumption and generation of electricity. Within the German coal market imported coal again compensated for the reduced contribution of indigenous coal. The indigenous coal mining industry has continued its politically prescribed decline according to plan. With the Council decision concerning coal subsidies in the EU, which came into force on 1 January 2011, and the deletion of the review clause in the Coal Financing Act approved by the German legislators cessation of the coal production in Germany at the end of 2018 has now become final and irreversible. At the same time the closure plan for the German coal mining industry extending to 2018 was approved by the EU Commission in December 2011. Meanwhile the RAG group is preparing its future after the end of the active mining industry inter alia by the use of available mining infrastructure for forms of renewable energy. (orig.)

  18. Petrographic and geochemical characterization of pale and dark brown coal from Yunnan Province, China

    Energy Technology Data Exchange (ETDEWEB)

    Ming, Q.; Xilin, R.; Dazhong, T.; Jian, X.; Wolf, M. [Aachen University, Aachen (Germany). Lehrstuhl fuer Geologie, Geochemie und Lagerstaetten des Erdoels und der Kohle

    1994-01-01

    Fifteen lignite samples from the province of Yunnan were analysed by organic petrography and geochemistry. Twelve of the samples represent the very pale (yellow) Baipao coal, the other three were normal coals of a medium brown colour. The Baipao coal consists mainly of mineral-bituminous groundmass, whereas the normal coal is characterised by well-preserved tissues derived from gymnosperm wood. Up to 190 mg/g C{sub org} of extract is extractable from the Baipao coal; only 63 mg/g C{sub org} from the normal coal. The n-alkaline fraction of the Baipao coal extract consists of high amounts of hopanes and shows the predominance of nor-abietane within the diterpenoids present. The first group of compounds points to intensive bacterial activity, while the second compound indicates not only that gymnosperms are present but also that a relatively oxygen-rich environment existed at the time of deposition. From the petrographic and organic geochemical characteristics it is concluded that the Baipao coal was formed from the same plant source material as the normal coal, but underwent stronger decay. 22 refs., 11 figs., 2 plates, 8 tabs.

  19. Induction of sister chromatid exchanges by coal dust and tobacco snuff extracts in human peripheral lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Tucker, J.D.; Ong, T.

    1985-01-01

    The organic solvent extracts of sub-bituminous coal dust and tobacco snuff, both together and separately, were tested for the induction of sister chromatid exchanges (SCEs) in human peripheral lymphocytes. The results indicate that these extracts induced SCEs, and that when tested together synergistically induced SCEs in two of three donors. Studies with the organic solvent extracts of all five ranks of coal indicate that the extracts of bituminous