Geological evaluation on productibility of coal seam gas; Coal seam gas no chishitsugakuteki shigen hyoka ni tsuite

Energy Technology Data Exchange (ETDEWEB)

Fujii, K [University of Shizuoka, Shizuoka (Japan). Faculty of Education

1996-09-01

Coal seam gas is also called coal bed methane gas, indicating the gas existing in coal beds. The gas is distinguished from the oil field based gas, and also called non-conventional type gas. Its confirmed reserve is estimated to be 24 trillion m {sup 3}, with the trend of its development seen worldwide as utilization of unused resource. For the necessity of cultivating relevant technologies in Japan, this paper considers processes of production, movement, stockpiling, and accumulation of the gas. Its productibility is controlled by thickness of a coal bed, degree of coalification, gas content, permeability, groundwater flow, and deposition structure. Gas generation potential is evaluated by existing conditions of coal and degree of coalification, and methane production by biological origin and thermal origin. Economically viable methane gas is mainly of the latter origin. Evaluating gas reserve potential requires identification of the whole mechanism of adsorption, accumulation and movement of methane gas. The gas is expected of effect on environmental aspects in addition to availability as utilization of unused energy. 5 figs.

Opportunities that abound for British coal--if only

Energy Technology Data Exchange (ETDEWEB)

1984-04-01

The chairman of the National Coal Board discusses primary-energy consumption from 1965, with major emphasis on coal. He points out that coal consumption showed growth after 1975, but before then - except for a boost in 1973 - real expansion has been quite slow. World coal resources and reserves are presented. Because several countries are able to deliver coal into Europe at prices which are lower than the National Coal Board's average cost, Britain must reduce production costs in order to compete more effectively worldwide. Patterns of costs could be improved if more output was to be concentrated at the modern, more-productive collieries. Investment in coal mining is at one of the highest levels of investment of any industry in Britain today.

A manuscript of De Saussure, Horace, Benedict on the origin of coal - Oratio de Lithantrace (1770) - science, business and environmental politics

Energy Technology Data Exchange (ETDEWEB)

Carozzi, A.V.; Newman, J.K. (Illinois University, Urbana, IL (USA). Dept. of Geology)

1993-05-01

18th century ideas about the origin of coal are presented. They ranged from thinking that coal and lignite were accumulations of resinous wood transported from forests to the sea, to coal being a shale impregnated by bituminous fluids, through to the idea, in 1778, that all types of coal are the products of peat having undergone different degrees of coalification.

Estimation for origin of coals on biomaker analysis; Jinko sekitan oyobi tennen sekitan no biomaker bunseki ni yoru sekitan kigen busshitsu no suitei

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Y. [Geological Survey of Japan, Tsukuba (Japan); Sugimoto, Y. [National Institute of Materials and Chemical Research, Tsukuba (Japan); Okada, K. [Coal Mining Research Center, Tokyo (Japan)

1996-10-28

In order to study coal production processes, an estimation study was carried out on coal originating materials by using biomaker analysis. Test samples are original coals collected directly from a mine in Hokkaido (not having been subjected cleaning). Mixing and solvent extraction were performed after pulverization, and then tests were given on saturated hydrocarbon components divided by using a silicagel column chromatograph for the present study. It can be known from n-alkane distribution in the coal that low molecular alkane increases with increasing degree of coalification. Artificial coal made by wet-heating Metasequoia leaves contains only little n-alkane. Diterpenoid compound exists in the Taiheiyo and Akabira coals. Tetra-cyclic diterpernoid is contained abundantly in subtropical coniferous trees, serving as a parameter for warm environment. The compound is contained also in the Fushun coal, but not in Indonesian coals. Hopanoid constitution shows very high similarity, but H/C atomic ratio may vary largely even if the coalification is at the same degree. This is likely to be caused from difference in originating materials. Hopanoids are bacteria attributed substances, whose activities are not affected by the originating materials. 2 figs., 1 tab.

Evaluation of paramagnetic species in coals with iodine doping technique; Yoso tenkaho wo mochiita sekitanchu no jojiseishu no hyoka

Energy Technology Data Exchange (ETDEWEB)

Aizawa, S.; Kumagai, H.; Chiba, T. [Hokkaido University, Sapporo (Japan). Center for Advanced Research of Energy Technology

1996-10-28

Electron paramagnetic resonance (EPR) of coals was considered by using iodine doping technique. Sub-bituminous coal (WA) and bituminous coal (UF) were used to observe EPR spectra using microwaves. With the UF coal, strength of the narrow component of the spectra was found constant regardless of amount of the doped iodine, wherein radicals without interaction with iodine were detected. Strength of the broad component increased with the iodine doping amount, where in deviation of {pi} electrons was detected, which have been generated as a result of interaction between aromatic rings and iodine in the coals. Spin concentration of the WA coal with low coalification degree is constant regardless of the iodine doping amount, and the interaction of the iodine with the aromatic rings was found small. The higher the coalification degree, the more the aromatic ring structure grows, and electron donor capability for the iodine increases. In a system with the entire spin being uniform, the spectrum height shows a saturation phenomenon against increase in microwave output. A non-uniform system, in which the oriented spin forms small groups and is in local thermal equilibrium, does not show saturation, but increases monotonously. 2 refs., 5 figs.

The Donets Basin (Ukraine/Russia): coalification and thermal history.

NARCIS (Netherlands)

Sachsenhofer, R.F.; Privalov, V.A.; Zhykalyak, M.V.; Bueker, C.; Panova, E.A.; Rainer, T.; Shymanovskyy, V.A.; Stephenson, R.A.

2002-01-01

The Donets Basin (Donbas) is one of the major late Paleozoic coal basins in the world. The Donbas Foldbelt is an inverted part of the Donets Basin characterized by WNW-ESE-trending folds and faults. The age of basin inversion is under discussion. Large parts of the Donets Basin host anthracite and

Detection of tannins in modern and fossil barks and in plant residues by high-resolution solid-state 13C nuclear magnetic resonance

Science.gov (United States)

Wilson, M.A.; Hatcher, P.G.

1988-01-01

Bark samples isolated from brown coal deposits in Victoria, Australia, and buried wood from Rhizophora mangle have been studies by high-resolution solid-state nuclear magnetic resonance (NMR) techniques. Dipolar dephasing 13C NMR appears to be a useful method of detecting the presence of tannins in geochemical samples including barks, buried woods, peats and leaf litter. It is shown that tannins are selectively preserved in bark during coalification to the brown coal stage. ?? 1988.

Compression map, functional groups and fossilization: A chemometric approach (Pennsylvanian neuropteroid foliage, Canada)

Science.gov (United States)

D'Angelo, J. A.; Zodrow, E.L.; Mastalerz, Maria

2012-01-01

Nearly all of the spectrochemical studies involving Carboniferous foliage of seed-ferns are based on a limited number of pinnules, mainly compressions. In contrast, in this paper we illustrate working with a larger pinnate segment, i.e., a 22-cm long neuropteroid specimen, compression-preserved with cuticle, the compression map. The objective is to study preservation variability on a larger scale, where observation of transparency/opacity of constituent pinnules is used as a first approximation for assessing the degree of pinnule coalification/fossilization. Spectrochemical methods by Fourier transform infrared spectrometry furnish semi-quantitative data for principal component analysis.The compression map shows a high degree of preservation variability, which ranges from comparatively more coalified pinnules to less coalified pinnules that resemble fossilized-cuticles, noting that the pinnule midveins are preserved more like fossilized-cuticles. A general overall trend of coalified pinnules towards fossilized-cuticles, i.e., variable chemistry, is inferred from the semi-quantitative FTIR data as higher contents of aromatic compounds occur in the visually more opaque upper location of the compression map. The latter also shows a higher condensation of the aromatic nuclei along with some variation in both ring size and degree of aromatic substitution. From principal component analysis we infer correspondence between transparency/opacity observation and chemical information which correlate with varying degree to fossilization/coalification among pinnules. ?? 2011 Elsevier B.V.

Detection of tannins in modern and fossil barks and in plant residues by high-resolution solid-state /sup 13/C nuclear magnetic resonance

Energy Technology Data Exchange (ETDEWEB)

Wilson, M A; Hatcher, P G

1988-01-01

Bark samples isolated from brown coal deposits in Victoria, Australia, and buried wood from Rhizophora mangle have been studied by high-resolution solid-state nuclear magnetic resonance (NMR) techniques. Dipolar dephasing /sup 13/C NMR appears to be a useful method of detecting the presence of tannins in geochemical samples including barks, buried woods, peats and leaf litter. It is shown that tannins are selectively preserved in bark during coalification to the brown coal stage. 28 refs., 9 figs., 1 tab.

Fluorescing macerals from wood precursors

Energy Technology Data Exchange (ETDEWEB)

Stout, S A; Bensley, D F

1987-01-01

A preliminary investigation into the origin of wood-derived macerals has established the existence of autofluorescent maceral precursors in the secondary xylem of swamp-inhabiting plant species. The optical character and fluorescent properties of microtomed thin-sections of modern woods from the Florida Everglades and Okefenokee Swamp, Georgia are compared to the character and properties of their peatified equivalents from various Everglades and Okefenokee peat horizons and their lignitic equivalents from the Brandon lignite of Vermont and the Trail Ridge lignitic peat from northern Florida. The inherent fluorescence of woody cell walls is believed to be caused by lignin though other cell wall components may contribute. The fluorescence spectra for several wood and cell types had a ..gamma../sub m//sub a//sub x/ of 452 nm and Q value of 0.00. The color as observed in blue light and the spectral geometry as measured in UV light of peatified and lignitic woody cell walls (potential textinites) may change progressively during early coalification. Cell wall-derived maceral material is shown to maintain its fluorescing properties after being converted to a structureless material, perhaps a corpohuminite or humodetrinite precursor. Fluorescing xylem cell contents, such as condensed tannins or essential oils, can maintain the fluorescent character through early coalification. Xylem cell walls and xylem cell contents are shown to provide fluorescing progenitor materials which would not require subsequent infusion with 'lipid' materials to account for their fluorescence as phytoclast material or as macerals in coal. 35 references.

International handbook of coal petrography. 2nd ed.

Energy Technology Data Exchange (ETDEWEB)

Crosdale, P. (ed.)

2001-07-01

This handbook is a CD-ROM version of the 1963 edition which was produced as a series of scanned tiff files with some corrections added. The handbook contains an alphabetical list of terms pertaining to brown coal petrography. Only terms recognised by a majority of experienced world petrographers are included. Generally, each of the terms contains sections on the origin of the term, a description of its constituents and properties, botanical affinities and genesis, alteration during coalification, occurrence and practical importance. Other sections cover other nomenclature systems, synonyms and analogous terms, and petrographic analysis methods.

Geological factors of the isotopic distribution of carbon of organic matter in sedimentary rocks

International Nuclear Information System (INIS)

Maass, J.

1981-01-01

The isotope ratio of carbon of fossile organic matter can be regarded as a definite criterion of its genetic origin. As the biofacial character of organic matter, especially the chemical composition (H/C-ratio), decisively influences the mode and quantity of the potential hydrocarbon production, isotopic analysis is an essential method for the prognostic evaluation of sedimentary basins with regard to their oil and gas perspectives. The genetic relations to the parent substance continue in the bituminization and coalification products and make it possible to apply the isotopic analysis of carbon to prospection work for hydrocarbons. (author)

Influence of chemical structure on carbon isotope composition of lignite

Science.gov (United States)

Erdenetsogt, Bat-Orshikh; Lee, Insung; Ko, Yoon-Joo; Mungunchimeg, Batsaikhan

2017-04-01

During the last two decades, a number of studies on carbon isotopes in terrestrial organic matter (OM) have been carried out and used to determine changes in paleoatmospheric δ13C value as well as assisting in paleoclimate analysis. Coal is abundant terrestrial OM. However, application of its δ13C value is very limited, because the understanding of changes in isotopic composition during coalification is relatively insufficient. The purpose of this study was to examine the influence of the chemical structure on the carbon isotope composition of lignite. Generally, lignite has more complex chemical structures than other higher rank coal because of the existence of various types of oxygen-containing functional groups that are eliminated at higher rank level. A total of sixteen Lower Cretaceous lignite samples from Baganuur mine (Mongolia) were studied by ultimate, stable carbon isotope and solid-state 13C CP/MAS NMR analyses. The carbon contents of the samples increase with increase in depth, whereas oxygen content decreases continuously. This is undoubtedly due to normal coalification process and also consistent with solid state NMR results. The δ13C values of the samples range from -23.54‰ to -21.34‰ and are enriched in 13C towards the lowermost samples. Based on the deconvolution of the NMR spectra, the ratios between carbons bonded to oxygen (60-90 ppm and 135-220 ppm) over carbons bonded to carbon and hydrogen (0-50 ppm and 90-135 ppm) were calculated for the samples. These correlate well with δ13C values (R2 0.88). The results indicate that the δ13C values of lignite are controlled by two mechanisms: (i) depletion in 13C as a result of loss of isotopically heavy oxygen-bounded carbons and (ii) enrichment in 13C caused by a loss of isotopically light methane from aliphatic and aromatic carbons. At the rank of lignite, coal is enriched in 13C because the amount of isotopically heavy CO2 and CO, released from coal as a result of changes in the chemical

Energy characteristics of finest coal particles surfaces versus their upgrading using flotation

Energy Technology Data Exchange (ETDEWEB)

Jerzy Sablik

2007-07-01

The paper presents selected results of investigations on energy properties of the fine coal particles, and methodological grounds for conducting such investigations. Using the discussed relationships, values of contact angle of coal particles with various degree of coalification in the range defined by the energy nonhomogeneity of the surfaces were computed. There have been determined the values of the contact angles of coal particles with hydrophobic and hydrophilic surfaces after coating with nonpolar and polar reagents. The energy state of the surfaces of coal particles in the feeds and products of industrial flotation were determined, which enabled to evaluate this process. 22 refs., 6 figs., 4 tabs.

Borane-catalyzed cracking of C-C bonds in coal; Boran-katalysierte C-C-Bindungungsspaltung in Steinkohle

Energy Technology Data Exchange (ETDEWEB)

Narangerel, J; Haenel, M W [Max-Planck-Institut fuer Kohlenforschung, Muelheim an der Ruhr (Germany)

1998-09-01

Coal, especially coking coal, was reacted with hydrogen at comparatively mild reaction conditions (150-280 degrees centigrade, 20 MPa hydrogen pressure) in the presence of catalysts consisting of borange reagents and certain transition metal halides to obtaine more than 80 percent of pyridine-soluble products. The influence of the degree of coalification, catalyst and temperature on the borane-catalyzed hydrogenolysis of C-C bonds in coal was investigated. (orig.) [Deutsch] Steinkohlen, insbesondere im Inkohlungsbereich der Fettkohlen (Kokskohlen), werden in Gegenwart von Katalysatoren aus Boran-Reagentien und bestimmten Uebergangsmetallhalogeniden mit Wasserstoff bei vergleichsweise milden Reaktionsbedingungen (250-280 C, 20 MPa Wasserstoffdruck) in zu ueber 80% pyridinloesliche Produkte umgewandelt. Der Einfluss von Inkohlungsgrad, Katalysator und Temperatur auf die Boran-katalysierte C-C-Bindungshydrogenolyse in Kohle wurde untersucht. (orig.)

Autofluorescence of fossil pollen and spores with special reference to age determination and coalification

NARCIS (Netherlands)

Gijzel, van Pieter

1967-01-01

In the present study the primary fluorescence phenomena of fossil pollen and spores are described. This new method in palynology is based on a large number of fluorescence microscopical observations and spectrophotometrical determinations of palynomorphs from deposits of various type and age. It

Black coal and lignite from biomass as fuel or alternative to carbon dioxide capture and storage; Stein- und Braunkohle aus Biomasse als Brennstoff oder als Alternative zur CO{sub 2}-Abscheidung und -Speicherung

Energy Technology Data Exchange (ETDEWEB)

Stengl, S.; Koch, C.; Scheer, J.; Stadlbauer, E.A.; Richarts, F.; Altensen, R.; Richter, H. [Technische Hochschule Mittelhessen (THM), Giessen (Germany); Weber, B. [Universidad Autonoma del Estado de Mexico (UAEM), Toluca (Mexico). Facultad de Ingenieria; Bayer, M.P.; Albert, K. [Tuebingen Univ. (Germany). Inst. fuer Organische Chemie

2012-05-15

This article refers to coalification of biomass in light of embedding this technique in the regional material flow management. From a process engineering point of view the focus is set on Hydrothermal Carbonization (HTC) and Low Temperature Conversion (LTC). Based on monosaccharides as building blocks of polysaccharides and ligneous biomass, the thermal behavior of glucose, fructose and xylose depending on reaction time and temperature is tracked. Consequently mainly hemicellulosic structures are affected under HTC conditions. However LTC converts both hemicelluloses as well as cellulose. The classification of HTC and LTC products from spent grains in terms of H/C and C/O ratio according to Meunier's coalification diagram ranges HTC coal in the area of lignite and the LTC coal in the area of black coal. This grading in terms of elementary analysis is confirmed by solid state{sup 13}C-NMR spectroscopy. The spectrum of LTC coal from spent grains fashioned at 400 C for duration of 3 h is undistinguishable from the spectrum of black coal. From the chemical point of view these two coals has to be described as identical. However the spectrum of the HTC product made of spent grains fashioned at 250 C for 3 h in a pressurized environment shows similarity to the spectrum of lignite. As engineering usage HTC products are a tool to convert cellulose-based residues in a uniform, high-energy matter for incineration processes. For this in-house waste management of e.g. breweries or sugar refineries could be enhanced. LTC coals are due to their stability eligible to extract CO{sub 2} from the atmosphere via photosynthesis and transfer carbon to the long-term stable geological cycle of matter. Consequential LTC offers an alternative to CCS. As a side effect LTC coals contribute to the elevation of carbon content in soils, which facilitates their water-holding and nutrient-holding capacity. (orig.)

Characterized hydrochar of algal biomass for producing solid fuel through hydrothermal carbonization.

Science.gov (United States)

Park, Ki Young; Lee, Kwanyong; Kim, Daegi

2018-06-01

The aim of this work was to study the characterized hydrochar of algal biomass to produce solid fuel though hydrothermal carbonization. Hydrothermal carbonization conducted at temperatures ranging from 180 to 270 °C with a 60 min reaction improved the upgrading of the fuel properties and the dewatering of wet-basis biomasses such as algae. The carbon content, carbon recovery, energy recovery, and atomic C/O and C/H ratios in all the hydrochars in this study were improved. These characteristic changes in hydrochar from algal biomass are similar to the coalification reactions due to dehydration and decarboxylation with an increase in the hydrothermal reaction temperature. The results of this study indicate that hydrothermal carbonization can be used as an effective means of generating highly energy-efficient renewable fuel resources using algal biomass. Copyright © 2018 Elsevier Ltd. All rights reserved.

Rare earth element patterns in nigerian coals

International Nuclear Information System (INIS)

Ewa, I.O.B.; Elegba, S.B.

1996-01-01

Rare Earth Elements (REE's) retain group coherence in their environment and are therefore useful geochemical markers. We report the pattern of ten REE's (La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Yb, Lu) determined by Instrumental Neutron Activation Analysis (INAA) for coals obtained from eight mines in Nigeria, namely, Okaba, Enugu, Ogbete, Onyeama, Gombe, Lafia, Asaba and Afikpo. Our results show the existence of fractionations with the highest index of 13.19 for Lafia coal, depletion in HREE, negative Eu anomaly for most of the coals, REE patterns that are consistent with chondritic trends; prominent (Eu/Eu * ) cn for Okaba and Gombe coals. Variations in geochemical data observed could suggest strong departures from band metamorphism during the coalification events of the Benue Trough geosynclines, where the coal deposits are all located. (author) 14 refs., 2 figs., 3 tabs

Coal Reservoir Physical Property Features and CBM Resource Potential in Xingtai Coal-bearing Region%邢台含煤区煤储层物性特征及煤层气资源潜力

Institute of Scientific and Technical Information of China (English)

高亮; 上官拴通; 张国斌; 李英英; 闫家栋

2017-01-01

为了评价邢台含煤区煤层气开发潜力,采集不同矿井的2、8、9号煤样进行了煤岩组分、孔裂隙分布、等温吸附及水单相渗透率实验分析,采用体积法和综合排队系数法对底板标高-2000 m以浅的煤层气资源量进行了预测和评价.结果表明:区内目的煤层厚度、煤级适中,具有较好的生储条件;煤岩的镜质组、惰质组和壳质组含量依次减少,水分随煤化程度的增加呈现先减小后增大,挥发分随煤化程度的增加而减少;孔隙度随煤化程度增大而增大,且孔径分布不均匀,微孔的孔容和比表面积所占比例最大;显微裂隙密度级别为一级,部分裂隙被脉状方解石和粒状黄铁矿充填;煤的吸附量受煤级控制,且在一定压力范围内,吸附量随压力增加而增大,吸附能力随压力增加而减小;煤层渗透率离散性较大,属中~高级渗透率.估算底板标高-2000 m以浅潜在的煤层气资源量为427.31亿m3,优选出中等有利区块6个,其中FY区、QHY区、GZ区为煤层气勘探首选区块.%To assess CBM exploitation potential in the Xingtai coal-bearing region, collected coal samples from coal seam Nos. 2, 8 and 9 in different coalmines, carried out experimental analysis of coal lithotype, pore and fissure distribution, isothermal adsorption and wa-ter single-phase permeability. Through the volumetric method and integrated queuing coefficient method carried out prediction and as-sessment of CBM resources above floor elevation-2000 m. The result has shown that the target coal thickness and coal rank are moder-ate, thus have better CBM generation and preservation conditions. Contents of coal macerals vitrinite, inertinite and exinite are sequen-tially deceasing;moisture content increasing along with coalification degree increasing presents deceasing first than increasing;volatile matter decreasing along with coalification degree increasing. Porosity is increasing along with coalification

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

Underground gasification of coal - possibilities and trends

International Nuclear Information System (INIS)

Dushanov, D.; Minkova, V.

1994-01-01

A detailed historical review is given on the problem of underground coal gasification (UCG) with emphasis on its physical, chemical, technological and financial aspects. The experience of USA, Japan, former USSR, Belgium, UK and France is described. The feasibility of UCG in the Dobrudzhan Coal Bed in Bulgaria is discussed. The deposit has reserves of about 1.5 billion tones at relatively shallow depths. Almost the whole scale from long flame to dry coal is covered. According to its coalification degree the bed belongs to gas coal - V daf 35-40%; C daf 80-83%, eruption index = 1. Enriched samples has low sulfur content - 0.6-1.5% and low mineral content - 6-12%. Having in mind the lack of domestic natural gas and petroleum resources, the authors state that the utilisation of the bed will alleviate the energy problems in Bulgaria. 24 refs., 5 figs., 1 tab

Maximum solid concentrations of coal water slurries predicted by neural network models

Energy Technology Data Exchange (ETDEWEB)

Cheng, Jun; Li, Yanchang; Zhou, Junhu; Liu, Jianzhong; Cen, Kefa

2010-12-15

The nonlinear back-propagation (BP) neural network models were developed to predict the maximum solid concentration of coal water slurry (CWS) which is a substitute for oil fuel, based on physicochemical properties of 37 typical Chinese coals. The Levenberg-Marquardt algorithm was used to train five BP neural network models with different input factors. The data pretreatment method, learning rate and hidden neuron number were optimized by training models. It is found that the Hardgrove grindability index (HGI), moisture and coalification degree of parent coal are 3 indispensable factors for the prediction of CWS maximum solid concentration. Each BP neural network model gives a more accurate prediction result than the traditional polynomial regression equation. The BP neural network model with 3 input factors of HGI, moisture and oxygen/carbon ratio gives the smallest mean absolute error of 0.40%, which is much lower than that of 1.15% given by the traditional polynomial regression equation. (author)

Proceedings of the papers of the 33rd Coal Science Conference (1996); Dai 33 kai sekitan kagaku kaigi happyo ronbunshu (1996)

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-10-28

This is a proceedings of the papers made public in the 33rd (fiscal 1996) Coal Science Conference held by the Japan Institute of Energy. The number of the papers included is 82. The processes such as coal liquefaction, coal gasification and pyrolysis are largely influenced by reaction of the carbon compound in coal. However, coal, which is different in reaction characteristics depending on its producing area, is a comprehensive compound. Therefore, the trial has been made for clarifying the molecular structure and skeleton. In the sense, the following papers are taken notice of: Suzuki and others` Estimation for origin of coals by biomaker analysis; Sugimoto and others` Change of unit skeletons during the artificial coalification; Hirado and others` Study on the correlation between chemical and mineral composition of coal ashes; Okawa and others` Coal structure construction system with construction knowledge and partial energy evaluation; Kanbayashi and others` Analysis of the relationship between coal properties and liquefaction characteristics by using the coal database.

Condensation reactions of glucose and aromatic ring; Glucose to hokokan tono shukugo hanno

Energy Technology Data Exchange (ETDEWEB)

Komano, T.; Mashimo, K.; Wainai, T.; Tanaka, C.; Yoshioka, T. [Nihon University, Tokyo (Japan). College of Science and Technology; Sugimoto, Y.; Miki, Y. [National Institute of Materials and Chemical Research, Tsukuba (Japan)

1996-10-28

For artificial coalification, condensation reactions of aromatic ring and activated compounds produced by dehydrating reaction of glucose were studied experimentally. In heat treatment experiment in water, three reaction specimens such as glucose, glucose and phenol, and glucose and benzaldehyde were fed into an autoclave together with distilled water, and subjected to reaction at 180{degree}C under spontaneous pressure for 50 hours. In hydrogenation experiment, the specimens were fed into an autoclave together with tetradecane and sulfurization catalyst, and subjected to reaction at 350{degree}C under initial pressure of 9.8MPa for 2 hours for gas chromatography (GC) analysis of products. As the experimental result, the reaction between glucose and aromatic ring in heat treatment in water occurred between aromatic ring and active fragment with a mean carbon number of 4-5 produced by decomposition of glucose. The reactivity was higher in benzaldehyde addition than phenol addition. 3 refs., 4 figs., 1 tab.

Nitrogen functionality of glucose-glycine condensate; Glucose to glycine tono shukugo hanno (shukugobutsuchu no chisso kagobutsu no keitai bunseki)

Energy Technology Data Exchange (ETDEWEB)

Tanaka, C.; Yoshioka, T.; Komano, T.; Mashimo, K.; Wainai, T. [Nihon University, Tokyo (Japan). College of Science and Technology; Sugimoto, Y.; : Miki, Y. [National Institute of Materials and Chemical Research, Tsukuba (Japan)

1996-10-28

In order to clarify a humification process in the early stage of coalification, the nitrogen functionality of prepared glucose-glycine condensate was studied experimentally. In experiment, the condensate was prepared by heating the mixture of glucose, glycine and water in a autoclave at 130{degree}C for 50 hours, and furthermore heating the produced solid material in water at 300{degree}C. After the condensate was hydrocracked, the fraction, condensate and hydrocracking residue were analyzed by elementary analyzer, {sup 13}C-NMR, XPS, FT-IR, capillary GC-FID/NPD and GC-MS. As a result, the glucose-glycine condensate could be arranged on the basis of three types of nitrogen such as pyridine, pyrrole and quaternary amine type. Pyridine type nitrogen increased, while quaternary amine type one decreased with an increase in heating treatment temperature. Rich pyrrole type nitrogen and poor pyridine type one were found in light nitrogen compounds in hydrocracked products. 2 refs., 4 figs., 2 tabs.

Research on the Composition and Distribution of Organic Sulfur in Coal.

Science.gov (United States)

Zhang, Lanjun; Li, Zenghua; Yang, Yongliang; Zhou, Yinbo; Li, Jinhu; Si, Leilei; Kong, Biao

2016-05-13

The structure and distribution of organic sulfur in coals of different rank and different sulfur content were studied by combining mild organic solvent extraction with XPS technology. The XPS results have shown that the distribution of organic sulfur in coal is related to the degree of metamorphism of coal. Namely, thiophenic sulfur content is reduced with decreasing metamorphic degree; sulfonic acid content rises with decreasing metamorphic degree; the contents of sulfate sulfur, sulfoxide and sulfone are rarely related with metamorphic degree. The solvent extraction and GC/MS test results have also shown that the composition and structure of free and soluble organic sulfur small molecules in coal is closely related to the metamorphic degree of coal. The free organic sulfur small molecules in coal of low metamorphic degree are mainly composed of aliphatic sulfides, while those in coal of medium and high metamorphic degree are mainly composed of thiophenes. Besides, the degree of aromatization of organic sulfur small molecules rises with increasing degree of coalification.

Characterization of Coal Quality Based On Ash Content From M2 Coal-Seam Group, Muara Enim Formation, South Sumatra Basin

Directory of Open Access Journals (Sweden)

Frillia Putri Nasution

2017-09-01

Full Text Available Muara Enim Formation is well known as coal-bearing formation in South Sumatra Basin. As coal-bearing formation, this formation was subjects of many integrated study. Muara Enim Formation can be divided into four coal-seam group, M1, M2, M3, and M4. The M2 group comprising of Petai (C, Suban (B, Lower Mangus (A2, and Upper Mangus (A1. Depositional environments of Group M2 is transitional lower delta plain with sub-depositional are crevasse splay and distributary channel. The differentiation of both sub-depositional environments can be caused the quality of coal deposit. One of quality aspects is ash content. This research conducted hopefully can give better understanding of relationship between depositional environments to ash content. Group M2 on research area were found only Seam C, Seam B, and Seam A2, that has distribution from north to central so long as 1400 m. Coal-seam thickness C ranged between 3.25-9.25 m, Seam B range 7.54-13.43 m, and Seam C range 1.53-8.37 m, where all of coal-seams thickening on the central part and thinning-splitting to northern part and southern part. The ash content is formed from burning coal residue material. Ash contents on coal seam caused by organic and inorganic compound which resulted from mixing modified material on surrounded when transportation, sedimentation, and coalification process. There are 27 sample, consists of 9 sample from Seam C, 8 sample from Seam B, and 10 sample from Seam A2. Space grid of sampling is 100-150 m. Ash content influenced by many factors, but in research area, main factor is existence of inorganic parting. Average ash content of Seam C is 6,04%, Seam B is 5,05%, and Seam A2 is 3,8%. Low ash content influenced by settle environment with minor detrital material. High ash content caused by oxidation and erosional process when coalification process. Ash content on coal in research area originated from detritus material carried by channel system into brackish area or originated

Developmental geology of coalbed methane from shallow to deep in Rocky Mountain basins and in Cook Inlet-Matanuska Basin, Alaska, USA and Canada

Science.gov (United States)

Johnson, R.C.; Flores, R.M.

1998-01-01

The Rocky Mountain basins of western North America contain vast deposits of coal of Cretaceous through early Tertiary age. Coalbed methane is produced in Rocky Mountain basins at depths ranging from 45 m (150 ft) to 1981 m (6500 ft) from coal of lignite to low-volatile bituminous rank. Although some production has been established in almost all Rocky Mountain basins, commercial production occurs in only a few. despite more than two decades of exploration for coalbed methane in the Rocky Mountain region, it is still difficult to predict production characteristics of coalbed methane wells prior to drilling. Commonly cited problems include low permeabilities, high water production, and coals that are significantly undersaturated with respect to methane. Sources of coalbed gases can be early biogenic, formed during the early stages of coalification, thermogenic, formed during the main stages of coalification, or late stage biogenic, formed as a result of the reintroduction of methane-gnerating bacteria by groundwater after uplift and erosion. Examples of all three types of coalbed gases, and combinations of more than one type, can be found in the Rocky Mountain region. Coals in the Rocky Mountain region achieved their present ranks largely as a result of burial beneath sediments that accumulated during the Laramide orogeny (Late Cretaceous through the end of the eocene) or shortly after. Thermal events since the end of the orogeny have also locally elevated coal ranks. Coal beds in the upper part of high-volatile A bituminous rank or greater commonly occur within much more extensive basin-centered gas deposits which cover large areas of the deeper parts of most Rocky Mountain basins. Within these basin-centered deposits all lithologies, including coals, sandstones, and shales, are gas saturated, and very little water is produced. The interbedded coals and carbonaceous shales are probably the source of much of this gas. Basin-centered gas deposits become overpressured

Interaction of uranium and organic matter in unaniferous sediments

Energy Technology Data Exchange (ETDEWEB)

Rouzaud, J N; Oberlin, A; Trichet, J

1980-01-01

Conventional transmission electron microscopy (lattice fringes and dark field techniques) was used for determining the structure and microtexture of some Precambrian organic matter. The samples came from Cluff (Saskatchewan, Canada) and Oklo (Gabon) and contain uranium with organo-metallic bonding (uranium was shown to be present by energy dispersive X-ray analysis carried out in the CTEM). Despite their algal origin, these materials show a high oxygen content. This strong degree of oxidation inhibits the parallel molecular orientation usually produced in carbonaceous products as coalification progresses. Progressive heat-treatment to 3000/sup 0/C produces microporous carbon (50 to 100A). It is, however, partially transformed into graphite in a manner similar to anthracites and non-graphitizable carbons heat-treated under pressure (5 kbars). It is favored by pore flattening, due to pressure, which introduces a long-range, preferred orientation parallel to the flattening plane. Conversely, it is partially prevented by cross-linking due to oxygen. Comparison with materials of higher plant origin (e.g. from Arlit, Niger) suggests a possible mechanism of uranium fixation.

Origin of natural gas; Tennen gas no kigen

Energy Technology Data Exchange (ETDEWEB)

Katayama, Y. [The Institute of Applied Energy, Tokyo (Japan)

1996-03-20

Natural gas, which is a general term of flammable hydrocarbon gases such as methane, is classified by origin into the following categories : (1) oil field gas (oil gas), (2) aquifers (bacteria-fermented methane), (3) coal gas (coal field gas), and (4) abiogenetic gas. The natural gas which has (1-4) origins and is now used as resource in a large quantity is (1) oil field gas. This gas is a hydrocarbon gas recovered in the production process of petroleum and contains components such as ethane, propane and butane. To the contrary, (2) aquifers and (3) coal gas have methane as main component. As (4) abiogenetic methane, there are gas formed in inorganic reaction in activities of submarine volcanos and deep gas (earth origin gas). Oil field gas has kerogen origin. Aquifers were formed by fermentation of organic matters. Coal gas was formed by coalification of vitrinite. As abiogenetic methane, there are inorganic reaction formation gas and deep gas, the latter of which exists little as resource. 7 refs., 11 figs., 1 tab.

Chemical evolution of Miocene wood: Example from the Belchatow brown coal deposit, central Poland

Science.gov (United States)

Drobniak, A.; Mastalerz, Maria

2006-01-01

Miocene conifer wood samples from the Belchatow brown coal deposit in Poland were studied in order to discuss a range of chemical variations that occur as a result of biochemical coalification. Petrographic analysis, ultimate analysis, electron microprobe technique, and FTIR spectroscopy were used in this study. Our data show several progressive trends in functional groups distribution that take place during the wood transformation from group 1 to group 4, such as an overall increase in aromaticity, an increase in lignin/cellulose ratio, and an increase in oxygen functionalities. Other observations include an increase in aliphatic stretching and bending functionalities from groups 1 to 3; followed by a decrease in the wood of group 4; appearance of aliphatic out-of-plane bands in group 3 and increase in group 4; an increase in CH2/CH3 in group 4 compared to the other groups; and decrease in O-H groups in group 4 compared to other groups. These observations, together with other chemical and petrological observations, indicate that the progressive elimination of cellulose and modification of lignin are dominant processes of the wood transformation. ?? 2005 Elsevier B.V. All rights reserved.

Report on the Sunshine Project in fiscal 1988 in research of coal liquefying technologies. Studies on direct hydrogenation liquefying reaction mechanism and prevention of carbonization; 1989 nendo sekitan no ekika gijutsu ni kansuru kenkyu hokokusho. Chokusetsu suiten ekika hanno kiko to tanka boshi no kenkyu

Energy Technology Data Exchange (ETDEWEB)

NONE

1989-07-01

This paper reports the research of coal liquefying technologies in the Sunshine Project in fiscal 1988. The research was performed with importance placed on the fundamentals of coal liquefaction and high value added compounds. Production of n-paraffin in the liquefying reaction occurs from reduction of acidic ester, and this ester structure contributes to cross-linking of aromatic rings. Most of the aromatic rings in coal has long side chains. A hypothesis was assumed that these chains have been produced from reaction of lignin in plants with fatty acid or alcohol. The hypothesis was verified from a synthesizing reaction by model substances. This could be said an initial reaction model for coalification. In order to verify de-alkylating reaction of the liquefied oil, model substances were used to investigate the products. Benzene having long alkyl side chains have the alkyl group dissociated, and on the other hand cyclization progressed producing naphthalene. Melting performance during coking is attributed to a great amount of solvent soluble low molecular constituents contained in coal. These constituents are contained in close contact in a net-like structure, which is loosened only by heating extraction, and extracted. They have no hydrogen donating performance. (NEDO)

Study on the correlation between chemical and mineral composition of coal ashes; Sekitanbaibun no kobutsu soseigakuteki kento kagakubutsu sosei to kobutsugakuteki sosei no sokan

Energy Technology Data Exchange (ETDEWEB)

Hirato, M.; Nagashima, S.; Okada, S. [Hachinohe Institute of Technology, Aomori (Japan)

1996-10-28

Coal ash is a substance that has been mixed into minerals in the earth`s crust during their coalification process. Estimation was made on what kinds of mineral composition have been mixed into coals. Noted first was the kinds of compounds contained in the ash, wherein the ratios of mass in the compounds and minerals were correlated, and selection was made on minerals which are thought correlated. The selection criterion was based on minerals containing silica, alumina, iron oxide, lime and magnesium as compounds. Then, a phase equilibrium line diagram was used to estimate compositions and melting points of minerals which are thought to have been produced from these compounds. By comparing the estimation with the measured melting points of the ashes, mineral compositions thought reasonable were all selected. Assumption was possible on minerals that are thought to have been transferred into coal ash. Compound indications of ashes from 29 kinds of the world`s typical coals were replaced with the subject minerals and expressed as mineral compositions. As a method of calculation, stoichiometric coefficients for each mineral were determined by taking material balance in atomic/molecular levels in masses of compound aggregates and mineral composition aggregates. 7 tabs.

Thermal stability of carboxylic acid functionality in coal; Sekitanchu ni sonzaisuru karubokishiruki no netsubunkai kyodo

Energy Technology Data Exchange (ETDEWEB)

Tsutsumi, Y.; Aida, T. [Kinki University, Osaka (Japan). Faculty of Engineering

1996-10-28

Carboxyl in coal was focused in discussing its pyrolytic behavior while tracking change of its absolute amount relative to the heating temperatures. A total of four kinds of coals, consisting of two kinds brown coals, sub-bituminous coal and bituminous coal were used. Change in the absolute amount of carboxyl due to heating varies with coalification degree. Decomposition starts in the bituminous coal from around 300{degree}C, and is rapidly accelerated when 400{degree}C is exceeded. Carboxyls in brown coals exist two to three times as much as those in bituminous and sub-bituminous coals, of which 40% is decomposed at a temperature as low as about 300{degree}C. Their pyrolytic behavior at temperatures higher than 400{degree}C resembles that of the bituminous coal. Carboxyls consist of those easy to decompose and difficult to decompose. Aromatic and aliphatic carboxylic acids with simple structure are stable at temperatures lower than 300{degree}C, and decompose abruptly from about 400{degree}C, hence their behavior resembles that of carboxyls in bituminous and sub-bituminous coals. Structure of low-temperature decomposing carboxyls in brown coals is not known, but it is assumed that humic acid originated from natural materials remains in the structure. 4 refs., 3 figs., 1 tab.

Isotopic variations in the nitrogen of natural humic and bituminous organic substances

International Nuclear Information System (INIS)

Stiehl, G.; Lehmann, M.

1980-01-01

delta 15 N-values and nitrogen contents of a series of humic and bituminous organic sediments of different ranks were determined. The change of the isotopic abundance of nitrogen was investigated during heating in model experiments, using a gas flame coal. In the case of humic carbon coals the relative nitrogen contents vary from 0.8 to 1.4% and the delta 15 N-values from + 3.5 to + 6.3 parts per thousand increasing from the brown coal to anthracite ranks. During the coalification process both the delta 15 N-values and the relative nitrogen contents do not vary continuously with the rank, but pass through maxima and minima. Model experiments using a gas flame coal show the same trend. Nitrogen with delta 15 N-values of + 2.8 or -7 parts per thousand was released in pyrolysis experiments, applying a gas flame coal and a steam coal at temperatures of 650 and 1000 0 C, respectively. The investigated bituminous sediments yielded relative amounts of 0.1 to 0.8% with delta 15 N-values of + 4.2 to + 10.7 parts per thousand. The obtained results are discussed with respect to the elucidation of nitrogen genesis in natural gas deposits. (author)

Working group report: methane emissions from coal mining

International Nuclear Information System (INIS)

Kruger, D.

1993-01-01

The process of coalification inherently generates methane and other byproducts. The amount of methane released during coal mining is a function of coal rank and depth, gas content, and mining methods, as well as other factors such as moisture. In most underground mines, methane is removed by drawing large quantities of air through the mine releasing the air into the atmosphere. In surface mines, exposed coal faces and surfaces, as well as areas of coal rubble created by blasting operations are believed to be the major sources of methane. A portion of the methane emitted from coal mining comes from post-mining activities such as coal processing, transportation, and utilisation. Some methane is also released from coal waste piles and abandoned mines. This paper highlights difficulties with previous methane emission studies namely: absence of data on which to base estimates; use of national data to develop global estimates; failure to include all possible emission sources; overreliance on statistical estimation methodologies. It recommends a 'tiered' approach for the estimation of emissions from underground mines, surface mines and post-mining activities. For each source, two or more approaches (or 'tiers') are presented, with the first tier requiring basic and readily available data and higher tiers requiring additional data. 29 refs., 3 tabs

In-Situ Microbial Conversion of Sequestered Greenhouse Gases

Energy Technology Data Exchange (ETDEWEB)

Scott, A R; Mukhopadhyay, M; Balin, D F

2012-09-06

The objectives of the project are to use microbiological in situ bioconversion technology to convert sequestered or naturally-occurring greenhouse gases, including carbon dioxide and carbon monoxide, into methane and other useful organic compounds. The key factors affecting coal bioconversion identified in this research include (1) coal properties, (2) thermal maturation and coalification process, (3) microbial population dynamics, (4) hydrodynamics (5) reservoir conditions, and (6) the methodology of getting the nutrients into the coal seams. While nearly all cultures produced methane, we were unable to confirm sustained methane production from the enrichments. We believe that the methane generation may have been derived from readily metabolized organic matter in the coal samples and/or biosoluble organic material in the coal formation water. This raises the intriguing possibility that pretreatment of the coal in the subsurface to bioactivate the coal prior to the injection of microbes and nutrients might be possible. We determined that it would be more cost effective to inject nutrients into coal seams to stimulate indigenous microbes in the coal seams, than to grow microbes in fermentation vats and transport them to the well site. If the coal bioconversion process can be developed on a larger scale, then the cost to generate methane could be less than $1 per Mcf

Methane flaring: an initiative in line with the greenhouse challenge

International Nuclear Information System (INIS)

Greenwood, D.

1999-01-01

Methane is a by-product of the coalification process. Once produced, it typically remains trapped within the coal seam and the surrounding strata. High quality black coals in Australia may contain up to 20 m 3 of methane per tonne of coal. In order to mine coal safely, this gas level must be reduced. Presence of gas at the coal face is a hazard as sparks created by coal extraction machine picks may ignite the gas/air mix. Concentrations of methane between approximately 5% and 15% in air create an explosive mixture. This represents a considerable potential safety risk for underground mining personnel. In Queensland, all underground mining personnel and equipment are protected by sensors that remove electrical power from machines should the ambient methane levels exceed 1.25%. While this assists in creating a safe working environment, it also halts coal production. Normal mine ventilation air removes a significant amount of methane, however in gassy mines the ventilation air flow required to maintain methane levels below the 1.25% limit can introduce other problems. These include excess airborne dust, which can lead to respiratory issues and poor visibility. A flare was installed at Central Colliery to achieve reduction of the greenhouse gas emissions. It would also be used to burn gas flow beyond that which can be effectively utilised by power generation

Agglomeration and reaction characteristics of various coal chars in fluidized-bed coal gasifier; Ryudoso sekitan gas ka ronai deno sekitan no gyoshu tokusei to hanno tokusei

Energy Technology Data Exchange (ETDEWEB)

Uemiya, S.; Aoki, K.; Mori, S.; Kojima, T. [Seikei University, Tokyo (Japan). Faculty of Engineering

1996-10-28

With relation to the coals delivered as common samples in the coal fundamental technology development project, an experimental study was conducted on agglomeration characteristics and reaction characteristics in the fluidized-bed coal gasifier. For the experiment, used was a fluidized bed gasifier inserted with a cone-shape dispersion plate with a nozzle in the center. After raising the temperature of the gasifier up to 773K, gasification was conducted sending to the gasifier air from the nozzle and steam from the dispersion plate. The mean particle diameter and gas concentration of chars were measured till the temperature reaches 1373K. As a result of the experiment, it was confirmed that the carbon conversion ratio increases with a decrease in coalification degree of the coal. Moreover, influence of the coal kind was markedly observed at the grid zone of the lower part of the bed, and it was clarified that the lower carbon content ratio the coal kind has, the faster the speed of CO formation and water gasification get. The agglomeration temperature of charcoal which is a product of the condensate is lower by as many as several hundred K than the point of softening, and it was considered to be necessary to study the relation with the temperature distribution in the bed. 3 refs., 3 figs., 1 tab.

Utilisation of chemically treated coal

International Nuclear Information System (INIS)

Bezovska, M.

2002-01-01

The numerous application of coal with high content of humic substances are known. They are used in many branches of industry. The complex study of the composition of coal from upper Nitra mines has directed research to its application in the field of ecology and agriculture. The effective sorption layers of this coal and their humic acids can trap a broad spectrum of toxic harmful substances present in industrial wastes, particularly heavy metals. A major source of humic acids is coal - the most abundant and predominant product of plant residue coalification. All ranks of coal contain humic acids but lignite from Novaky deposit represents the most easily available and concentrated from of humic acids. The possibilities of utilisation of humic acids to remove heavy metals from waste waters was studied. The residual concentrations of the investigated metals in the aqueous phase were determined by AAs. From the results follows that the samples of coals humic acids can be used for the heavy metal removal from metal solutions and the real acid mine water. Oxidised coal with high content of humic acids and nitrogen is used in agriculture as fertilizer. Humic acids are active component in coal and can help to utilize almost quantitatively nitrogen in soil. The humic substances block and stabilize toxic metal residues already present in soil. (author)

Compression-cuticle relationship of seed ferns: Insights from liquid-solid states FTIR (Late Palaeozoic-Early Mesozoic, Canada-Spain-Argentina)

Science.gov (United States)

Zodrow, E.L.; D'Angelo, J. A.; Mastalerz, Maria; Keefe, D.

2009-01-01

Cuticles have been macerated from suitably preserved compressed fossil foliage by Schulze's process for the past 150 years, whereas the physical-biochemical relationship between the "coalified layer" with preserved cuticle as a unit has hardly been investigated, although they provide complementary information. This relationship is conceptualized by an analogue model of the anatomy of an extant leaf: "vitrinite (mesophyll) + cuticle (biomacropolymer) = compression". Alkaline solutions from Schulze's process as a proxy for the vitrinite, are studied by means of liquid-solid states Fourier transform infrared spectroscopy (FTIR). In addition, cuticle-free coalified layers and fossilized cuticles of seed ferns mainly from Canada, Spain and Argentina of Late Pennsylvanian-Late Triassic age are included in the study sample. Infrared data of cuticle and alkaline solutions differ which is primarily contingent on the mesophyll +biomacropolymer characteristics. The compression records two pathways of organic matter transformation. One is the vitrinized component that reflects the diagenetic-post-diagenetic coalification history parallel with the evolution of the associated coal seam. The other is the cuticle that reflects the sum-total of evolutionary pathway of the biomacropolymer, its monomeric, or polymeric fragmentation, though factors promoting preservation include entombing clay minerals and lower pH conditions. Caution is advised when interpreting liquid-state-based FTIR data, as some IR signals may have resulted from the interaction of Schulze's process with the cuticular biochemistry. A biochemical-study course for taphonomy is suggested, as fossilized cuticles, cuticle-free coalified layers, and compressions are responses to shared physicogeochemical factors. ?? 2009 Elsevier B.V. All rights reserved.

Studies on coal vitrinoid substances and their carbonized products. Volumes I and II

Energy Technology Data Exchange (ETDEWEB)

Davis, A

1965-01-01

The purposes of this research were to investigate some of the physical and chemical properties of coal vitrinoid substances and the changes in those properties which occurred during the carbonization of the vitrinoids and to compare, wherever possible the processes of coalification and carbonization. The construction and use of a direct reading reflectometer is described and tests which revealed that the average maximum and minimum reflectances obtained from particulate blocks of vitrinoid could be accepted as approximations of the true maximum and minimum reflectances. Reflectance determinations upon oriented samples formed the basis of this research and lead to the suggestion that there are two overlapping segments of the curve relating reflectance to either carbon content of aromaticity. The apparent step in reflectance is considered to be at least partly due to a mottling of the lower-reflecting vitrinoids caused by a marked difference in appearance of various of the coalified plant cell wall layers and cell contents. Various of the properties of the vitrinoids, including behavior upon carbonization, indicated that the lower-reflecting group of vitrinoids from Northumberland and North Durham were all of lower rank than other, higher-reflecting vitrinoids, in spite of the overlapping carbon content. The changes in density, optical properties and chemical analyses of the vitrinoids following carbonization at temperatures up to 600C are described: increase in reflectance is reported for some low-rank vitrinoids carbonized at 200C and significant changes in the anisotropy of some carbonized vitrinoids are given in terms of bireflectance.

Uranium trace and alpha activity characterization of coal and fly ash using particle track etch technique

International Nuclear Information System (INIS)

Chakravarti, S.K.

1991-01-01

Uranium is extensively found in carbonaceous components of sedimentary rocks and is considered to be accumulated in coals during the coalification process through the geological times. Burning of coal is mainly responsible for a manifold increase in the concentration of radioactive nuclides in atmosphere precipitates. Fly ash being an incombustible residue and formed from 90% of the inorganic material in coal, escapes into the atmosphere and constitutes a potential hazard. Also its use as one of the pozzolanic materials in the products of concrete, bricks etc and filling of ground cavities is even more hazardous because of the wall radioactivity, besides emission and diffusion of radon. This paper reports a simple method called Particle Track Etch (PTE) technique, for trace determination of uranium content in coal and fly ash samples by making use of low cost and versatile plastic detectors known as Solid State Nuclear Track Detectors (SSNTDs). Total alpha activity has also been estimated using these SSNTDs. The values of uranium concentration in coal samples are found to range from 1.1 to 3.6 ppm (uniform component) and 33 to 46 ppm (non-uniform part) whereas in fly ash, it varies from 8 to 11 ppm (uniform) and 55 to 71 ppm in non-uniform range. It is also observed that the alpha activity is a function of uranium concentration for most of the natural samples of coal studied except for mixtures of fly ash samples where relationship is found to be on higher side. (author). 13 refs., 2 tabs., 1 fig

Compression-cuticle relationship of seed ferns: Insights from liquid-solid states FTIR (Late Palaeozoic-Early Mesozoic, Canada-Spain-Argentina)

Energy Technology Data Exchange (ETDEWEB)

Zodrow, Erwin L. [Palaeobotanical Laboratory, Cape Breton University, Sydney, Nova Scotia (Canada); D' Angelo, Jose A. [Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales (IANIGLA), CCT-CONICET-Mendoza, Avda. Ruiz Leal s/n Parque Gral. San Martin (5500) Mendoza (Argentina); Area de Quimica, Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Centro Universitario - M5502JMA - Mendoza (Argentina); Mastalerz, Maria [Indiana Geological Survey, Indiana University, 611 North Walnut Grove, Bloomington, IN 47405-2208 (United States); Keefe, Dale [Molecular Spectroscopy Research Laboratory, Department of Chemistry, Cape Breton University, Sydney, Nova Scotia (Canada)

2009-08-01

Cuticles have been macerated from suitably preserved compressed fossil foliage by Schulze's process for the past 150 years, whereas the physical-biochemical relationship between the ''coalified layer'' with preserved cuticle as a unit has hardly been investigated, although they provide complementary information. This relationship is conceptualized by an analogue model of the anatomy of an extant leaf: ''vitrinite (mesophyll) + cuticle (biomacropolymer) = compression''. Alkaline solutions from Schulze's process as a proxy for the vitrinite, are studied by means of liquid-solid states Fourier transform infrared spectroscopy (FTIR). In addition, cuticle-free coalified layers and fossilized cuticles of seed ferns mainly from Canada, Spain and Argentina of Late Pennsylvanian-Late Triassic age are included in the study sample. Infrared data of cuticle and alkaline solutions differ which is primarily contingent on the mesophyll +biomacropolymer characteristics. The compression records two pathways of organic matter transformation. One is the vitrinized component that reflects the diagenetic-post-diagenetic coalification history parallel with the evolution of the associated coal seam. The other is the cuticle that reflects the sum-total of evolutionary pathway of the biomacropolymer, its monomeric, or polymeric fragmentation, though factors promoting preservation include entombing clay minerals and lower pH conditions. Caution is advised when interpreting liquid-state-based FTIR data, as some IR signals may have resulted from the interaction of Schulze's process with the cuticular biochemistry. A biochemical-study course for taphonomy is suggested, as fossilized cuticles, cuticle-free coalified layers, and compressions are responses to shared physicogeochemical factors. (author)

13C-NMR Study on Structure Evolution Characteristics of High-Organic-Sulfur Coals from Typical Chinese Areas

Directory of Open Access Journals (Sweden)

Qiang Wei

2018-02-01

Full Text Available The structure evolution characteristics of high-organic-sulfur (HOS coals with a wide range of ranks from typical Chinese areas were investigated using 13C-CP/MAS NMR. The results indicate that the structure parameters that are relevant to coal rank include CH3 carbon (fal*, quaternary carbon, CH/CH2 carbon + quaternary carbon (falH, aliphatic carbon (falC, protonated aromatic carbon (faH, protonated aromatic carbon + aromatic bridgehead carbon (faH+B, aromaticity (faCP, and aromatic carbon (farC. The coal structure changed dramatically in the first two coalification jumps, especially the first one. A large number of aromatic structures condensed, and aliphatic structures rapidly developed at the initial stage of bituminous coal accompanied by remarkable decarboxylation. Compared to ordinary coals, the structure evolution characteristics of HOS coals manifest in three ways: First, the aromatic CH3 carbon, alkylated aromatic carbon (faS, aromatic bridgehead carbon (faB, and phenolic ether (faP are barely relevant to rank, and abundant organic sulfur has an impact on the normal evolution process of coal. Second, the average aromatic cluster sizes of some super-high-organic-sulfur (SHOS coals are not large, and the extensive development of cross bonds and/or bridged bonds form closer connections among the aromatic fringes. Moreover, sulfur-containing functional groups are probably significant components in these linkages. Third, a considerable portion of “oxygen-containing functional groups” in SHOS coals determined by 13C-NMR are actually sulfur-containing groups, which results in the anomaly that the oxygen-containing structures increase with coal rank.

Influence of the hydrothermal dewatering on the combustion characteristics of Chinese low-rank coals

International Nuclear Information System (INIS)

Ge, Lichao; Zhang, Yanwei; Xu, Chang; Wang, Zhihua; Zhou, Junhu; Cen, Kefa

2015-01-01

This study investigates the influence of hydrothermal dewatering performed at different temperatures on the combustion characteristics of Chinese low-rank coals with different coalification maturities. It was found that the upgrading process significantly decreased the inherent moisture and oxygen content, increased the calorific value and fixed carbon content, and promoted the damage of the hydrophilic oxygen functional groups. The results of oxygen/carbon atomic ratio indicated that the upgrading process converted the low-rank coals near to high-rank coals which can also be gained using the Fourier transform infrared spectroscopy. The thermogravimetric analysis showed that the combustion processes of upgraded coals were delayed toward the high temperature region, and the upgraded coals had higher ignition and burnout temperature. On the other hand, based on the higher average combustion rate and comprehensive combustion parameter, the upgraded coals performed better compared with raw brown coals and the Da Tong bituminous coal. In ignition segment, the activation energy increased after treatment but decreased in the combustion stage. The changes in coal compositions, microstructure, rank, and combustion characteristics were more notable as the temperature in hydrothermal dewatering increased from 250 to 300 °C or coals of lower ranks were used. - Highlights: • Typical Chinese lignites with various ranks are upgraded by hydrothermal dewatering. • Upgraded coals exhibit chemical compositions comparable with that of bituminous coal. • FTIR show the change of microstructure and improvement in coal rank after upgrading. • Upgraded coals exhibit difficulty in ignition but combust easily. • More evident effects are obtained for raw brown coal with relative lower rank.

Meeting of Commission of International Committee on Petrology of Coals

Energy Technology Data Exchange (ETDEWEB)

Timofeev, P P; Bogolyubova, L I

1982-03-01

In Urbana, Illinois from 18-20 May 1979 the XXXII session of the International Committee on Petrology met. Reports were made on standards for the study of bituminous and anthracite coals. Use of reflective capacity of vitrain to determine coalification of coals was discussed along with a proposition to establish numerical boundaries between brown, bituminous and anthracite coals. The re-editing of the International Dictionary on Petrology of Coals was agreed upon in view of new facts on microcomponents of coal and methods of studying them. The next meeting of the Commission took place at Ostrav, Czechoslovakia from 14-26 April 1980. At the plenary session, new officials were elected and agreement to re-edit the Dictionary on Petrology of Coals was confirmed. At the meeting of the Commission on Coal Petrography the question of the determination of components of coal by quantitative diagnosis, and results of determining components of vitrain by measuring its reflective capacity were reported on. At the meeting of the Committee on Applying Facts of Petrology in Geology, the classification of solid oil bitumen and organic substance of sediments was discussed. At the meeting of the Committee on the Application of the Petrology of Coals in Industry, attention was given to discussing basic parameters for the international classification of coals to be presented at the meeting of the Economic Commission of Europe in Geneva. In the final plenary session of the commission, results of discussions were summarized. The next session was to be held in France in 1981. (In Russian)

Coalbed methane: new frontier

Energy Technology Data Exchange (ETDEWEB)

Eaton, S.

2003-02-01

There are large numbers of stacked coal seams permeated with methane or natural gas in the Western Canadian Sedimentary Basin, and approximately 20 coalbed methane pilot projects are operating in the area, and brief descriptions of some of them were provided. Coalbed methane reserves have a long life cycle. A definition of coalbed methane can be a permeability challenged reservoir. It is not uncommon for coalbed methane wells to flow water for periods varying from 2 to 6 months after completion before the production of natural gas. A made-in-Canada technological solution is being developed by CDX Canada Inc., along with its American parent company. The techniques used by CDX are a marriage between coal mining techniques and oil and gas techniques. A brief description of coalification was provided. Nexen is participating in the production of gas from an Upper Mannville coal at 1 000-metres depth in a nine-well pilot project. The Alberta Foothills are considered prime exploration area since older coal is carried close to the surface by thrusting. CDX Canada uses cavitation completion in vertical wells. Cavitation consists in setting the casing above the coal seam and drilling ahead under balanced. The design of wells for coalbed methane gas is based on rock and fluid mechanics. Hydraulic fracturing completions is also used, as are tiltmeters. An enhanced coalbed methane recovery pilot project is being conducted by the Alberta Research Council at Fenn-Big Valley, located in central Alberta. It injects carbon dioxide, which shows great potential for the reduction of greenhouse gas emissions. 1 figs.

Utilisation of chemically treated coal

Directory of Open Access Journals (Sweden)

Bežovská Mária

2002-03-01

Full Text Available The numerous application of coal with high content of humic substances are known. They are used in many branches of industry. The complex study of the composition of coal from upper Nitra mines has directed research to its application in the field of ecology and agriculture. The effective sorption layers of this coal and their humic acids can to trap a broad spectrum of toxic harmful substances present in industrial wastes, particularly heavy metals. A major source of humic acids is coal - the most abundant and predominant product of plant residue coalification. All ranks of coal containt humic acids but lignite from Nováky deposit represents the most easily available and concentrated form of humic acids. Deep oxidation of coal by HNO3 oxidation - degradation has been performed to produce water-soluble-organic acids. The possibilities of utilisation of oxidised coal and humic acids to remove heavy metals from waste waters was studied. The residual concentrations of the investigated metals in the aqueous phase were determined by AAs. From the results follows that the samples of oxidised coal and theirs humic acids can be used for the heavy metal removal from metal solutions and the real acid mine water.Oxidised coal with a high content of humic acids and nitrogen is used in agriculture a fertilizer. Humic acids are active component in coal and help to utilize almost quantitatively nitrogen in soil. The humic substances block and stabiliz toxic metal residues already present in soil.

Comparison of the associative structure of two different types of rich coals and their coking properties

Energy Technology Data Exchange (ETDEWEB)

Hengfu Shui; Changhui Lin; Meng Zhang; Zhicai Wang; Mingdong Zheng [Anhui University of Technology, Maanshan (China). School of Chemistry and Chemical Engineering

2010-07-15

Solvent extractions of two different types of Chinese rich coals i.e. Aiweiergou coal (AG) and Zaozhuang coal (ZZ) using the mixed solvent of carbon disulfide/N-methyl-2-pyrrolidinone (CS{sub 2}/NMP) with different mixing ratios were carried out and the caking indexes of the extracted residues were measured. It was found that the extracted residues from the two types of coals showed different changing tendencies of the caking indexes with the extraction yield. When the extraction yield attained about 50% for ZZ coal, the extracted residue had no caking property. However for AG coal, when the extraction yield reached the maximum of 63.5%, the corresponding extracted residue still had considerable caking property with the caking index of 25. This difference indicated the different associative structure of the two coals although they are of the same coalification. Hydro-thermal treatment of the two rich coals gave different extract fractionation distributions for the treated coals compared to those of raw coals respectively. The coking property evaluations of the two coals and their hydro-thermally treated ones were carried out in a crucible coking determination. The results showed that the hydro-thermal treatment could greatly improve the micro-strengths of the resulting coke from the two coals, and the improvement was more significant for the more aggregated AG coal. The reactivities of hydro-thermally treated AG coal blends were almost the same as those of raw coal blends. The higher coke reactivities of AG raw coal and its hydro-thermally treated ones than those of ZZ coal might be attributed to its special ash composition. 20 refs.,4 figs., 5 tabs.

Nitrogen emissions during pyrolysis and combustion; Einfluesse auf die Stickstofffreisetzung bei der Pyrolyse und Verbrennung

Energy Technology Data Exchange (ETDEWEB)

Koepsel, R F; Friebel, J; Halang, S [Technische Univ. Bergakademie Freiberg (Germany). Inst. IEC

1998-09-01

Reduction of nitric oxide emissions during brown coal combustion is an important contribution to clean utilisation of this very important domestic primary energy source. In modern processes, the nitrogen contained in the fuels is the main source of oxides. The distribution of this nitrogen in the products can be influenced by modifying the degassing parameters especially in the first phase of combustion, i.e. pyrolysis. The heat-up rate, pressure, as well as the genesis and mineral content of the coal were found to be the main influencing paramters. Depending on the fuel characteristics (degree of coalification, concentration of volatile matter, ash composition), the nitrogen released during pyrolysis and the nitrogen retained in the solid residue contribute to the total emissions of nitric oxides in different degrees. (orig.) [Deutsch] Die Verminderung der Stickoxidemission bei der Verbrennung von Braunkohle stellt einen wichtigen Beitrag zur sauberen Verwertung dieses bedeutendsten einheimischen Primaerenergietraegers dar. In modernen Prozessen bildet dabei der im Brennstoff gebundene Stickstoff die Hauptquelle der Oxide. Insbesondere durch Einflussnahme auf die Entgasungsbedingungen waehrend der ersten Phase der Verbrennung - der Pyrolyse - kann die Verteilung dieses Stickstoffes auf die Produkte beeinflusst werden. Als wesentliche Einflussgroessen auf die Einbindung in den verbleibenden Koks und die Freisetzung fluechtiger N-haltiger Gase (HCN, NH{sub 3}) wurden die Aufheizgeschwindigkeit, der Druck und die Mineralsubstanz der Kohle gefunden. Eine wesentliche Einflussgroesse stellt daneben auch die Herkunft der Kohlen dar. In Abhaengigkeit von den Brennstoffeigenschaften (Inkohlungsgrad, Gehalt an fluechtigen Bestandteilen, Aschezusammensetzung) tragen der waehrend der Pyrolyse freigesetzte und der im festen Rueckstand verbleibende Stickstoff in unterschiedlichem Masse zur Gesamtemission an Stickoxiden bei. (orig.)

Petrography and microanalysis of Pennsylvanian coal-ball concretions (Herrin Coal, Illinois Basin, USA): Bearing on fossil plant preservation and coal-ball origins

Science.gov (United States)

Siewers, Fredrick D.; Phillips, Tom L.

2015-11-01

Petrographic analyses of 25 coal balls from well-studied paleobotanical profiles in the Middle Pennsylvanian Herrin Coal (Westphalian D, Illinois Basin) and five select coal balls from university collections, indicate that Herrin Coal-ball peats were permineralized by fibrous and non-fibrous carbonates. Fibrous carbonates occur in fan-like to spherulitic arrays in many intracellular (within tissue) pores, and are best developed in relatively open extracellular (between plant) pore spaces. Acid etched fibrous carbonates appear white under reflected light and possess a microcrystalline texture attributable to abundant microdolomite. Scanning electron microscopy, X-ray diffraction, and electron microprobe analysis demonstrate that individual fibers have a distinct trigonal prism morphology and are notable for their magnesium content (≈ 9-15 mol% MgCO3). Non-fibrous carbonates fill intercrystalline spaces among fibers and pores within the peat as primary precipitates and neomorphic replacements. In the immediate vicinity of plant cell walls, non-fibrous carbonates cut across fibrous carbonates as a secondary, neomorphic phase attributed to coalification of plant cell walls. Dolomite occurs as diagenetic microdolomite associated with the fibrous carbonate phase, as sparite replacements, and as void-filling cement. Maximum dolomite (50-59 wt.%) is in the top-of-seam coal-ball zone at the Sahara Mine, which is overlain by the marine Anna Shale. Coal-ball formation in the Herrin Coal began with the precipitation of fibrous high magnesium calcite. The trigonal prism morphology of the carbonate fibers suggests rapid precipitation from super-saturated, meteoric pore waters. Carbonate precipitation from marine waters is discounted on the basis of stratigraphic, paleobotanical, and stable isotopic evidence. Most non-fibrous carbonate is attributable to later diagenetic events, including void-fill replacements, recrystallization, and post-depositional fracture fills. Evidence

Impact of organic-mineral matter interactions on thermal reaction pathways for coal model compounds

Energy Technology Data Exchange (ETDEWEB)

Buchanan, A.C. III; Britt, P.F.; Struss, J.A. [Oak Ridge National Lab., TN (United States). Chemical and Analytical Sciences Div.

1995-07-01

Coal is a complex, heterogeneous solid that includes interdispersed mineral matter. However, knowledge of organic-mineral matter interactions is embryonic, and the impact of these interactions on coal pyrolysis and liquefaction is incomplete. Clay minerals, for example, are known to be effective catalysts for organic reactions. Furthermore, clays such as montmorillonite have been proposed to be key catalysts in the thermal alteration of lignin into vitrinite during the coalification process. Recent studies by Hatcher and coworkers on the evolution of coalified woods using microscopy and NMR have led them to propose selective, acid-catalyzed, solid state reaction chemistry to account for retained structural integrity in the wood. However, the chemical feasibility of such reactions in relevant solids is difficult to demonstrate. The authors have begun a model compound study to gain a better molecular level understanding of the effects in the solid state of organic-mineral matter interactions relevant to both coal formation and processing. To satisfy the need for model compounds that remain nonvolatile solids at temperatures ranging to 450 C, model compounds are employed that are chemically bound to the surface of a fumed silica (Si-O-C{sub aryl}linkage). The organic structures currently under investigation are phenethyl phenyl ether (C{sub 6}H{sub 5}CH{sub 2}CH{sub 2}OC{sub 6}H{sub 5}) derivatives, which serve as models for {beta}-alkyl aryl ether units that are present in lignin and lignitic coals. The solid-state chemistry of these materials at 200--450 C in the presence of interdispersed acid catalysts such as small particle size silica-aluminas and montmorillonite clay will be reported. Initial focus will be on defining the potential impact of these interactions on coal pyrolysis and liquefaction.

Measurement of reflectance of coal macerals: its automation and significance

Energy Technology Data Exchange (ETDEWEB)

Davis, A.

1978-06-01

A prime objective of the Pennsylvania State University's DOE program is the characterization of 1,300 samples of U.S. coals. Reflectance determination plays a major role in meeting this objective, because it is used as an accurate rank index both to select coals for testing and to investigate property-behavior interrelationships using the Penn State/DOE Coal Data Base. Reflectances of coal macerals are related to their refractive and absorptive indices by the Beer equation; the refractive index of the medium and the wavelength of light need to be specified. Determinations usually are made in immersion oil at 546 nm. Properties of vitrinite make it the most suitable maceral for these measurements, but the variety of vitrinite selected may depend upon the intended application. Vitrinite reflectance is considered to be dependent upon the degree of aromatization of its structural units. Although some of the earlier investigators believed that the reflectance of coals increased in a discontinuous, stepped manner as their rank increased, the bulk of assembled data suggests that the change is continuous. Some recent results indicate that there may be more than one coalification track for coals with different geological histories, resulting in displacement from the general trend. Several techniques have been employed to determine the optical properties of coal constituents. Usual comparative method involves the use of a microscope photometer to compare the intensity of light reflected by particles within a polished pellet of coal to that of a glass or synthetic mineral standard. Because coal is anisotropic it is common to measure either maximum reflectance in polarized light or random reflectance in non-polarized light. Various eqipment modifications and accessories have been used to improve the ease of measuring maximum reflectance.

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

Energy Technology Data Exchange (ETDEWEB)

Glombitza, C.; Mangelsdorf, K.; Horsfield, B. [German Research Cemter of Geoscience GFZ, Potsdam (Germany)

2009-10-15

Several lignites and coals of low to moderate maturation levels from the New Zealand Coal Band were investigated using alkaline ester cleavage experiments to reveal compositional changes of ester bound components during increasing maturation. Ester bound alcohols are found to be present in highest amounts in the very immature lignite samples but show a rapid decrease during early diagenesis. Ester bound fatty acids also show an initial exponential decrease during diagenesis but reveal an intermittent increase during early catagenesis before decreasing again during main catagenesis. This was related to the short chain fatty acids. To obtain a maturity related signal and to eliminate facies related scattering in the amounts of fatty acids in the coal samples, the carbon preference index of fatty acids (CPIFA) parameter is introduced. For the long chain fatty acids the CPIFA decreases with increasing maturity. During diagenesis, the same trend can be observed for the short chain fatty acids but the intermittent increase in the amounts of short chain fatty acids is also accompanied by high CPIFA values. This indicates less altered organic biomass at this maturation level and is in contrast to the mature CPIFA signal of the long chain fatty acids of the same samples. Thus could be due to extremely different amounts of short and long chain fatty acids in the original source organic matter or it could due to the incorporation of immature bacterial biomass from deep microbial communities containing C{sub 16} and C{sub 18} 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. The high amounts of alcohols in the immature lignite samples are also visible in the alkene distribution from the open system pyrolysis experiments of the organic matrix before and after saponification.

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...... increase during early catagenesis before decreasing again during main catagenesis. This intermittent increase was related to the short chain fatty acids. To obtain a maturity related signal and to eliminate facies related scattering in the amounts of fatty acids in the coal samples, the carbon preference...

Origin of natural waters and gases within the Upper Carboniferous coal-bearing and autochthonous Miocene strata in South-Western part of the Upper Silesian Coal Basin, Poland

International Nuclear Information System (INIS)

Kotarba, Maciej J.; Pluta, Irena

2009-01-01

The molecular and stable isotope compositions of coalbed gases from the Upper Carboniferous strata and natural gases accumulated within the autochthonous Upper Miocene Skawina Formation of the Debowiec-Simoradz gas deposit were determined, as well as the chemical and stable isotope compositions of waters from the Skawina Formation and waters at the top of the Upper Carboniferous strata of the Kaczyce Ridge (the abandoned 'Morcinek' coal mine) in the South-Western part of the Upper Silesian Coal Basin. Two genetic types of natural gases within the Upper Carboniferous coal-bearing strata were identified: thermogenic (CH 4 , small amounts of higher gaseous hydrocarbons, and CO 2 ) and microbial (CH 4 , very small amounts of ethane, and CO 2 ). Thermogenic gases were generated during the bituminous stage of coalification and completed at the end of the Variscan orogeny. Degassing (desorption) of thermogenic gases began at the end of late Carboniferous until the late Miocene time-period and extended to the present-day. This process took place in the Upper Carboniferous strata up to a depth of about 550 m under the sealing Upper Miocene cover. A primary accumulation zone of indigenous, thermogenic gases is present below the degassing zone. Up to 200 m depth from the top of the Upper Carboniferous strata, within the weathered complex, an accumulation zone of secondary, microbial gas occurs. Waters within these strata are mainly of meteoric origin of the infiltration period just before the last sea transgression in the late Miocene and partly of marine origin having migrated from the Upper Miocene strata. Then, both methanogenic archaebacteria and their nutrients were transported by meteoric water into the near-surface Carboniferous strata where the generated microbial CH 4 saturated coal seams. Waters within the Miocene strata of the Debowiec-Simoradz and Zablocie are of marine origin, and natural gases accumulated within autochthonous Miocene strata of the Debowiec

Oxidation and carbonisation of coals: a case study of coal fire affected coals from the Wuda coalfield, Inner Mongolia, China

Science.gov (United States)

Kus, Jolanta; Meyer, Uwe; Ma, Jianwei; Chen-Brauchler, Dai

2010-05-01

At the coalfield of Wuda (Inner Mongolia, PR China) extensive underground coal fires cause widespread thermal and oxidative effects in coal seams. Within phase B of the Coal Fire Research Project of the Sino-German Initiative, methods for innovative fire-extinguishing technologies were investigated in multifaceted research approaches. Extensive investigations of oxidative and thermally affected coal seams in coal fire zone 18 were conducted in 2008 prior to application of new fire-extinguishing methods. We present results from the outcrop of coal seam No. 4 in the fire zone 18. The coal of seam No. 4 is of Early Permian age and belongs stratigraphically to the Shanxi Formation. The unaffected coal displays a high volatile bituminous A rank with a background value of random vitrinite reflectance ranging from 0.90 to 0.96 % Rr. Coal channel samples were coallected at actively extracted coal faces along multiple profiles with surface temperatures ranging from about 50° to 600°C. Microscopic examinations revealed a variety of products of coal exposure to the fire. Within coal samples, a marked rise in vitrinite reflectance from background values to 5.55% Rr (6.00 % Rmax) is encountered. In addition, a number of coal samples showed suppressed vitrinite reflectances ranging between 0.82 to 0.88% Rr. Further, seemingly heat unaffected coal samples display intensive development of oxidations rims at coal grain edges and cracks as well as shrinkage cracks and formation of iron oxides/hydroxides. Instead, thermally affected coal samples with higher coalification grade are further characterised by development of macropores (devolatilisation pores) in vitrinitic streaks, transformation of liptinite to meta-liptinite and micrinite as well as by natural coke particles of mostly porous nature and fine to coarse grained anisotropic mosaic. Coal petrographic investigations confirmed a hypothesis that both, oxidations as well as low temperature carbonisation govern the thermal

Anatomy of an intruded coal, I: Effect of contact metamorphism on whole-coal geochemistry, Springfield (No. 5) (Pennsylvanian) coal, Illinois Basin

Energy Technology Data Exchange (ETDEWEB)

Rimmer, Susan M. [Department of Geology, Southern Illinois University Carbondale, Carbondale, IL 62901 (United States); Yoksoulian, Lois E. [Department of Earth and Environmental Sciences, University of Kentucky, Lexington, KY 40506 (United States); Hower, James C. [Center for Applied Energy Research, University of Kentucky, 2540 Research Park Drive, Lexington, KY 40511 (United States)

2009-08-01

If time and heating rate are important agents in coal maturation, one might expect to see differences in chemical changes in response to maturation depending on the means of increased rank. Using a suite of samples obtained from an intruded Pennsylvanian-age coal in southern Illinois, we present whole-coal chemical data. Comparing these data to extant geochemical data for coals that have undergone normal burial maturation, we evaluated the hypothesis that if coal alteration occurs rapidly (due to intrusion) rather than gradually (burial maturation), then different relationships are seen in chemical composition (proximate and ultimate analyses) and vitrinite reflectance. The Pennsylvanian-age (Asturian [Westphalian D]) Springfield (No. 5) coal is mined at the Big Ridge Mine, near Eldorado, southern Illinois. This high volatile B bituminous coal was intruded by an ultramafic igneous intrusion during the early Permian. Alteration occurs out to {proportional_to} 1.2 x dike thickness and includes an increase in random vitrinite reflectance (R{sub m}) from levels {proportional_to} 0.7% to over 5.3%, loss of liptinites, and formation of devolatilization vacuoles and fine mosaic texture. Decreases in volatile matter (VM) and increases in fixed carbon (FC) appear to be less than would be expected for the level of reflectance seen within the alteration halo. Carbonate minerals have a major influence on proximate analyses but even following the removal of carbonates, the decrease in VM is still less than would be seen in coals of similar vitrinite reflectance that were altered by normal burial maturation. Carbonate mineralization also contributes to variability in ultimate analysis values approaching the intrusion, particularly for %C and %O. After carbonate removal, data for these coals do not appear to follow the normal burial coalification tracks when plotted on a van Krevelen diagram and on a Seyler chart. These differences suggest that a slightly different maturation

The coalification profile of the Grambach 1 exploration well - first indication of an oil kitchen in the molasse basin; Das Inkohlungsprofil der Bohrung Grambach 1 - erster Hinweis auf eine ``Oelkueche`` im Molassebecken

Energy Technology Data Exchange (ETDEWEB)

Hiltmann, W.; Wehner, H. [Bundesanstalt fuer Geowissenschaften und Rohstoffe, Hannover (Germany); Kuckelkorn, K. [Niedersaechsisches Landesamt fuer Bodenforschung, Hannover (Germany)

1999-06-01

For the first time an exploration well beneath the German part of the Alpine overthrust zone met vitrinite reflectance values raising up to 1,6% R{sub r} - and this in a widespread tectonic high position. The interpretation as an oil and gas kitchen is confirmed by oil maturity (derived by biomarkers and carbon isotope ratios). (orig.) [Deutsch] Erstmals traf im deutschen Teil der alpinen Ueberschiebungszone eine Bohrung ein bis 1,6% R{sub r} ansteigendes Inkohlungsprofil an und dies in einer ausgedehnten Hochscholle. Die Interpretation als `Oel- und Gaskueche` wurde durch die Reife des zugeschlossenen Erdoels (Biomarker, Kohlenstoffisotopen) bestaetigt. (orig.)

Organic petrology, mineralogy and depositional environment of the Kipra lignite seam, Maritza-West basin, Bulgaria

Energy Technology Data Exchange (ETDEWEB)

Kostova, Irena [Department of Geology and Palaeontology, Sofia University ' ' St. Kliment Ohridski' ' , 1000, Sofia (Bulgaria); Zdravkov, Alexander [Department of Economic Geology, University of Mining and Geology ' ' St. Ivan Rilski' ' , 1700, Sofia (Bulgaria)

2007-08-01

The aim of the present study is to provide additional information about the properties and depositional environment of the Kipra lignite seam, which was deposited during the regressive stage of development of the Maritza-West basin. Petrographical and mineralogical data, along with ash yields and sulphur contents of 24 samples from a seam profile, have been used to study the vertical variation of the depositional settings during peat accumulation and subsequent coalification. The Kipra lignite is characterized by high ash yields and sulphur contents. It formed in a rheotrophic, low-lying mire with alkaline pH value. Vegetation with low preservation potential dominated within the palaeomire. During peat formation, frequent changes of the water level controlled the depositional environment. During the deposition of units 1 and 2, high water energy caused the transportation of high amounts of inorganic material into the mire, resulting in the formation of weakly gelified mineral-rich lignite. The organic matter from units 3 and 4 is characterized by enhanced gelification, which probably reflects the decreasing energy of the system. Good positive correlation between sulphur contents and the GI values was established in units 4, indicating that the gelification of the tissues was probably mainly controlled by the bacterial activity. In contrast, the gelification of the samples from unit 3 of the Kipra seam was probably governed by the redox conditions. The organic matter deposited under relatively wet conditions, in which the thermal and oxidative destruction of the tissues, was limited. A variety of major, minor and accessory minerals are present in Maritza-West lignite. The mineral composition is dominated mainly by pyrite, gypsum and calcite, and to a lesser extent limonite, quartz, kaolinite, montmorillonite, illite, chlorite and plagioclase. Jarosite, hematite, halloysite, mica, K-feldspar, aragonite, siderite, and dolomite were also determined in very low

Volcanic ash in feed coal and its influence on coal combustion products

Energy Technology Data Exchange (ETDEWEB)

Brownfield, M.E.; Affolter, R.H.; Cathcart, J.D.; Brownfield, I.K.; Hower, J.C.; Stricker, G.D.; O' Connor, J.T.

2000-07-01

peat-forming mire. Dissolution and alteration of these minerals occurred either in the peat-forming sate or during coalification/diagenesis contributing to the authigenic mineral suite. Additionally, detrital mineral input and epigenetic ground-water flow may have affected the geochemistry of the feed coal.

The coalification profile of the Grambach 1 exploration well - first indication of an oil kitchen in the molasse basin. Das Inkohlungsprofil der Bohrung Grambach 1 - erster Hinweis auf eine ''Oelkueche'' im Molassebecken

Energy Technology Data Exchange (ETDEWEB)

Hiltmann, W.; Wehner, H. (Bundesanstalt fuer Geowissenschaften und Rohstoffe, Hannover (Germany)); Kuckelkorn, K. (Niedersaechsisches Landesamt fuer Bodenforschung, Hannover (Germany))

1999-06-01

For the first time an exploration well beneath the German part of the Alpine overthrust zone met vitrinite reflectance values raising up to 1,6% R[sub r] - and this in a widespread tectonic high position. The interpretation as an oil and gas kitchen is confirmed by oil maturity (derived by biomarkers and carbon isotope ratios). (orig.)

Methanogenic pathways of coal-bed gas in the Powder River Basin, United States: The geologic factor

Energy Technology Data Exchange (ETDEWEB)

Flores, Romeo M.; Rice, Cynthia A.; Stricker, Gary D.; Warden, Augusta; Ellis, Margaret S. [U.S. Geological Survey, Box 25046, MS 939, Denver, Colorado 80225 (United States)

2008-10-02

decrease of methane composition of the coal-bed gas. Other geologic factors, such as burial, thermal and maturation history, lateral and vertical continuity, and coalification of the coal beds, also played a significant role in controlling methanogenic pathways and provided new perspectives on gas evolution and emplacement. The early-stage gas produced by CO{sub 2} reduction has mixed with transitional thermogenic gas in the deeper, central parts of the Powder River Basin to form 'old' gas, whereas along the basin margins the overprint of gas from methyl-type fermentation represents 'new' gas. Thus, a clear understanding of these geologic factors is necessary to relate the microbiological, biogeochemical, and hydrological processes involved in the generation of coal-bed gas. (author)

Interaction and the structures of coal

Science.gov (United States)

Opaprakasit, Pakorn

solvents, which in turn enhances the coal extraction yield. Finally, the evidence for the presence of a glass transition temperature in coal was examined. The results from Differential Scanning Calorimetry showed that no transition similar to the Tg can be observed in bulk coal or its low-molecular weight fraction, pyridine soluble extracted material, at a temperature near 110°C. In contrast, an irreversible transition that is due to water evaporation has been found. Thermomechanical measurements, which are very sensitive to the presence of a Tg in synthetic polymers, also provided no evidence for a Tg below temperatures where chemical reactions occur. Additionally, the results from Thermomechanical Analysis showed an expansion in size when the coal was heated to 300°C, which is associated with a "caking" process. The degree of expansion during this "caking" process is about five times greater in the direction perpendicular to the bedding plane than the parallel, indicating an accommodation of anisotropic strain relaxation, which was generated in the direction perpendicular to the bedding plane during the coalification process.

Application of automated image analysis to coal petrography

Science.gov (United States)

Chao, E.C.T.; Minkin, J.A.; Thompson, C.L.

1982-01-01

The coal petrologist seeks to determine the petrographic characteristics of organic and inorganic coal constituents and their lateral and vertical variations within a single coal bed or different coal beds of a particular coal field. Definitive descriptions of coal characteristics and coal facies provide the basis for interpretation of depositional environments, diagenetic changes, and burial history and determination of the degree of coalification or metamorphism. Numerous coal core or columnar samples must be studied in detail in order to adequately describe and define coal microlithotypes, lithotypes, and lithologic facies and their variations. The large amount of petrographic information required can be obtained rapidly and quantitatively by use of an automated image-analysis system (AIAS). An AIAS can be used to generate quantitative megascopic and microscopic modal analyses for the lithologic units of an entire columnar section of a coal bed. In our scheme for megascopic analysis, distinctive bands 2 mm or more thick are first demarcated by visual inspection. These bands consist of either nearly pure microlithotypes or lithotypes such as vitrite/vitrain or fusite/fusain, or assemblages of microlithotypes. Megascopic analysis with the aid of the AIAS is next performed to determine volume percentages of vitrite, inertite, minerals, and microlithotype mixtures in bands 0.5 to 2 mm thick. The microlithotype mixtures are analyzed microscopically by use of the AIAS to determine their modal composition in terms of maceral and optically observable mineral components. Megascopic and microscopic data are combined to describe the coal unit quantitatively in terms of (V) for vitrite, (E) for liptite, (I) for inertite or fusite, (M) for mineral components other than iron sulfide, (S) for iron sulfide, and (VEIM) for the composition of the mixed phases (Xi) i = 1,2, etc. in terms of the maceral groups vitrinite V, exinite E, inertinite I, and optically observable mineral

Evaluation of the quality, thermal maturity and distribution of potential source rocks in the Danish part of the Norwegian–Danish Basin

Directory of Open Access Journals (Sweden)

Kristensen, Lars

2008-11-01

Middle Jurassic Haldager Sand play. Potential trap structures are widely distributed in the basin, most commonly associated with the flanks of salt diapirs. The plays rely on charge from the Lower Jurassic (Toarcian or uppermost Jurassic – lowermost Cretaceous shales. Both plays have been tested with negative results, however, and failure is typically attributed to insufficient maturation (burial depth of the source rocks. This maturation question has been investigated by analysis of vitrinite reflectance data from the study area, corrected for post-Early Cretaceous uplift. A likely depth to the top of the oil window(vitrinite reflectance = 0.6%Ro is c. 3050–3100 m based on regional coalification curves. The Frederikshavn Formation had not been buried to this depth prior to post-Early Cretaceous exhumation,and the potential source rocks of the formation are thermally immature in terms of hydrocarbon generation. The potential source rocks of the Fjerritslev Formation are generally immature to very early mature. Mature source rocks in the Danish part of the Norwegian–Danish Basin are thus dependent on local, deeper burial to reach the required thermal maturity for oil generation. Such potential kitchen areas with mature Fjerritslev Formation source rocks may occur in the central part of the study area (central–northern Jylland, and a few places offshore. These inferred petroleum kitchens are areally restricted, mainly associated with salt structures and local grabens (such as the Fjerritslev Trough and the Himmerland Graben.

Organic petrography:An approach for identification of maceral groups in Gheshlagh coal area, Eastern Alborz

Directory of Open Access Journals (Sweden)

Tahereh Rabani

2016-07-01

Full Text Available Introduction Maceral is a term to introduce organic components visible under a microscope (Stopes, 1935. The physical and chemical characteristics of macerals such as elemental composition, moisture content, hardness, density and petrographic characteristics differ. The differences in the physical and chemical characteristics of macerals are reflected in their industrial behavior.(Parkash, 1985. Petrographic analysis provides information on the various physical components of coals (Suwarna and Hemanto, 2007 and determination of quality of coal, coalification rate, composition and characteristics of coke and paleoenvironmental deposition (Taylor et al., 1998. Sampling and methodology Coal samples were collected from freshly mined coal from 11 coal seams of 4 active coal mines (Cheshlagh, Zemestan Yourt, Narges Chal and Cheshmehsaran for organic petrography in the Gheshlagh coal deposits. All samples were collected and stored in plastic bags to prevent contamination and weathering. Samples were prepared for microscopic analysis by reflected light following ASTM Standard procedure D2797-04. For microscopic study, coal samples were crushed to1-mm size fraction (18 mesh size, mounted in epoxy resin and polished. Three polished samples were prepared for each coal seam. The petrographic composition was obtained by maceral analyses under standard conditions (ISO 7404/3, 2009, for maceral analysis. Maceral point counting (based on 400 points analyses were performed using an Olympus BX51 reflected light microscope. The terminology used to identify and describe the organic matter particles is the one proposed by the International Committee for Coal and Organic Petrology (ICCP, 1998; ICCP, 2001; Scott and Glasspool, 2007; Taylor et al., 1998; Stach et al., 1982; Hower et al., 2009; Hower and Wagner, 2012. Organic petrography of theGheshlagh coal seams The vitrinite maceral group is dominant in all coal seams (66.2 to 87.2 vol.% and includes collodetrinite