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Characterization of surface properties of coals by film flotation
01 Solid fuels (sources, winning, properties)
O1
SOLID FUELS Sources, winning, properties
02/01244 A rapid coal characterisation analysis by lowresolution NMR spectroscopy and partial least-squares regression Harmer, J.R. et al. Fuel, 2001, 80, (9), 1341-1349. IH-NMR spectroscopy is a potentially useful technique for the characterization of coal. A novel technique was applied to distinguish, characterize and determine quantitatively five different classes of proton containing components from air-dried Australian bituminous coals. The five different classes of protons are described by 14 fitted NMR parameters, which are the signal amplitudes, spin-lattice relaxation times and spin-spin relaxation times. To establish the mathematical relationship between the 14 fitted N M R parameters and the properties of a large set of bituminous Australia coals, a partial least-squares (PLS) regression algorithm was used. Predictions were accurate for many coal properties, particularly those related to the organic matter of the coal. The method is therefore, a rapid (25 rain) method for coal quality monitoring with potential for commercial application.
02/01245 A study of chemical structure in 'barkinite' using time-of-flight secondary ion mass spectrometry Sun, X. et al. Int. J. Coal Geol., 2001, 47, (1), 1-8. The Late Permian coals from south China are unique in their high content of 'barkinite' and elemental hydrogen, and typically produce high yields of tar. 'Barkinite' has often been identified as suberinite for a long time, but now many Chinese workers have concluded that 'barkinite' is not suberinite, rather it is a distinct maceral. The term 'barkinite' was formally certified and named by the State Bureau of Technical Supervision of the People's Republic of China in 1991, 1995 and 1999; however, it has not been recognized as a scientific term by international coal geologists and ICCP, and TSOP have not recognized the term, either. The petrographic characteristics of 'barkinite' and suberinite show that the biggest difference between them is in the cell fillings. Therefore, in the paper, a new in situ microprobe mass chemical analysis method, time-of-flight secondary ion mass spectrometry (TOP-SIMS) was first used to study the chemical structure of cell walls and cell fillings of 'barkinite'. The results indicate that the chemical structures of cell fillings and cell walls are similar to each other. They are all mostly composed of aliphatic compounds (such as alkane and alkene), and followed by aromatic compounds and alkyl aromatics, in addition to minor amounts of heteroaromatic compounds (such as alkoxyl and alkylamine). Based on these, it can be deduced that the cell cavities of 'barkinite' were mainly filled by original lipid, which were derived from cell secretion of 'barkinite' itself. But suberinite is defined only as suberinized cell walls in cork tissue, and cell cavities were usually filled by secondary gelification materials (such as corpocollinite), these characteristics are quite different from those of 'barkinite'. The chemical characteristics of "barkinite' shown in SIMS spectra coincide with those inferred from its petrographic characteristics. The high content of hydrogen, the high tar yields and the high hydrocarbon generation potential of Late Permian coals from south China are attributed to the high aliphatic content of 'barkinite'.
02/01246 Anatomic-morphological method of phyteral analysis of the coals andcoalbeds of Ukraine Uziyuk, V.I. Geol. Geokhim. Goryuch. Kopalin, 1999, 4, 53-65. (In Ukrainian) This is a review of the phyteral analysis of coal, focusing on the process of plant tissue transformation into coal, and terminology and classification aspects.
02/01247 Application of neutralization potential on the balance of acid-base reactions in lignite mining Schopke, R. et al. Grundwasser, 2001, 6, (1), 23-29. (In German) Acidic conditions of seepage and groundwater originating from open pit minings in Lusatia (Germany) are described using the neutralization potential, which is based on the concept of acidity. Acid formation and buffer reactions can be reduced to three elemental reactions: oxidation of pyrite/reduction of sulfate, dissolution of carbonate, and gypsum equilibrium. These reactions are combined in a genetic model in order to interpret the origin of mineral and acid contents of different groundwaters influenced by lignite mining. The statistical results of these calculations are summarized to calibrate parameters of a prognostic model. The method described here is used to prepare restoration measures.
164 Fuel and Energy Abstracts May 2002
02/01248 Ash quality of a beneficiated lignite from Ptolemais Basin, Northern Greece Vamvuka, D. et al. Energy FueL~, 2001, 15, (5), 1181-1185. A density separation method was used to reduce ash components, which form fireside deposits during coal combustion, as well as trace elements, in a Greek lignite. Standard techniques were applied to predict the slagging and fouling propensity of clean coal and to determine the trace elements concentration in this. Deposition tendencies were established through the use of empirical indexes for lignitic type ashes. Significant reductions in ash content (up to 60%) were achieved by dense liquid separation of the lignite. Coal cleaning diminished the slagging and fouling 16otential of the feed, reflecting some alterations in the chemical and mineralogy of the ash-forming components. The ash of beneficiated materials was richer in the basic oxides, while poorer in quartz. Also, the ash fusion temperatures (initial deformation and hemispherical) were significantly increased, though the contents of quartz and anhydrite remained high. Most trace elements were found to be associated with the mineral phase. Removal efficiency was low by the density separation method, but the environmental impact of these elements is anticipated to be negligible.
02/01249 Carbon reactivity in an oxygen plasma; a comparison with reactivity in molecular oxygen Cuesta, A. et al. Carbon, 200l, 39, (8), l 135-1146. Reactivity upon immersion in an oxygen plasma is studied in this paper on 46 different carbons and coals. Suitable parameters are chosen to characterize the plasma reactivity of these materials. The observed plasma reactivity trend is compared with the 02 reactivity trend shown by the same set of materials. Differences are discussed in terms of the influence of structural, chemical and textural factors upon carbon gasification in both media. To help discern these influences, multiple regression is applied to the factors derived from a principal components analysis. In contrast with 02 reactivity, oxygen plasma reactivity shows a more feeble dependence on structural factors and none on chemical factors. On the other hand, reactivity dependence from surface area appears to be stronger for the oxygen plasma than for 02. The above observations are interpreted as a corroboration of the Rideal-type mechanism proposed for the carbon--oxygen plasma reaction by Rosner and Allendorf.
02/01250 Characterization of surface properties of coals by film flotation. Sablik, J. and Wierzchowski, K. Zesz. Nauk. Politech. S/ask., Gorn., 2000, 246, (1), 451-466. (In Polish) Coal surface properties were studied using the film flotation technique. The critical wetting surface tension and surface energy heterogeneity depended on the coal rank. These values can be controlled by depositing chemical reagents on the coal surface, resulting in properties advantageous to the coal treatment method.
02/01251 Coal content of the Middle Carboniferous sediments of the Lvov-Volyn Basin Byk, S.I. Geol. Geokhim. Goryuch. Kopalin, 1999, 4, 48-52. (In Ukrainian) Drilling data on the coal concentration in the Middle Carboniferous rocks of the Lvov-Volyn Basin were studies. The main characteristics of coal concentration such as the thickness of the Middle Carboniferous sediments, the number of coal beds, the overall coal seam thickness and the ratio of general-to-industrial coal content were calculated and the directions of their changes throughout the area were analysed. The thickness of deposits increases in the west and northwest directions, and the increase rates are higher in the north and southwest parts of the basin than in its central part. The number of coal beds and interbeds increases from the east to the west, reaching 16-18 maximum North (Volyn field) and southwest (Tyagliv and Kariv fields) parts of the basin have the highest coal contents. A close relation between the thickness of the Middle Carboniferous rocks and the number of coal beds in them was established. The overall coal bed thickness is comparatively small (mainly less than two meters), and the trend in thickness changes is analogous to the changes in the abovementioned two parameters throughout the area. The ratio of coal availability is characterized by low values and homogeneity, almost throughout the whole area of the basin it ranges between 1-2, with the exception of the extreme west areas of the Volyn and Zabuzhian fields and the central, the most dipping parts of the Tyagliv and Kariv fields, where it increases up to 2.5-3.2. A conclusion was drawn that the most favourable conditions for accumulation of organic matter in the deposits of the Bashkir stage occurred to the north and southwest of the basin, and that improvement of such conditions and raise in rates of coal material accumulation happened in the direction of basin opening (that is to say, from the east to the west, in the direction of the Lublin Basin).
O1
SOLID FUELS Sources, winning, properties
02/01244 A rapid coal characterisation analysis by lowresolution NMR spectroscopy and partial least-squares regression Harmer, J.R. et al. Fuel, 2001, 80, (9), 1341-1349. IH-NMR spectroscopy is a potentially useful technique for the characterization of coal. A novel technique was applied to distinguish, characterize and determine quantitatively five different classes of proton containing components from air-dried Australian bituminous coals. The five different classes of protons are described by 14 fitted NMR parameters, which are the signal amplitudes, spin-lattice relaxation times and spin-spin relaxation times. To establish the mathematical relationship between the 14 fitted N M R parameters and the properties of a large set of bituminous Australia coals, a partial least-squares (PLS) regression algorithm was used. Predictions were accurate for many coal properties, particularly those related to the organic matter of the coal. The method is therefore, a rapid (25 rain) method for coal quality monitoring with potential for commercial application.
02/01245 A study of chemical structure in 'barkinite' using time-of-flight secondary ion mass spectrometry Sun, X. et al. Int. J. Coal Geol., 2001, 47, (1), 1-8. The Late Permian coals from south China are unique in their high content of 'barkinite' and elemental hydrogen, and typically produce high yields of tar. 'Barkinite' has often been identified as suberinite for a long time, but now many Chinese workers have concluded that 'barkinite' is not suberinite, rather it is a distinct maceral. The term 'barkinite' was formally certified and named by the State Bureau of Technical Supervision of the People's Republic of China in 1991, 1995 and 1999; however, it has not been recognized as a scientific term by international coal geologists and ICCP, and TSOP have not recognized the term, either. The petrographic characteristics of 'barkinite' and suberinite show that the biggest difference between them is in the cell fillings. Therefore, in the paper, a new in situ microprobe mass chemical analysis method, time-of-flight secondary ion mass spectrometry (TOP-SIMS) was first used to study the chemical structure of cell walls and cell fillings of 'barkinite'. The results indicate that the chemical structures of cell fillings and cell walls are similar to each other. They are all mostly composed of aliphatic compounds (such as alkane and alkene), and followed by aromatic compounds and alkyl aromatics, in addition to minor amounts of heteroaromatic compounds (such as alkoxyl and alkylamine). Based on these, it can be deduced that the cell cavities of 'barkinite' were mainly filled by original lipid, which were derived from cell secretion of 'barkinite' itself. But suberinite is defined only as suberinized cell walls in cork tissue, and cell cavities were usually filled by secondary gelification materials (such as corpocollinite), these characteristics are quite different from those of 'barkinite'. The chemical characteristics of "barkinite' shown in SIMS spectra coincide with those inferred from its petrographic characteristics. The high content of hydrogen, the high tar yields and the high hydrocarbon generation potential of Late Permian coals from south China are attributed to the high aliphatic content of 'barkinite'.
02/01246 Anatomic-morphological method of phyteral analysis of the coals andcoalbeds of Ukraine Uziyuk, V.I. Geol. Geokhim. Goryuch. Kopalin, 1999, 4, 53-65. (In Ukrainian) This is a review of the phyteral analysis of coal, focusing on the process of plant tissue transformation into coal, and terminology and classification aspects.
02/01247 Application of neutralization potential on the balance of acid-base reactions in lignite mining Schopke, R. et al. Grundwasser, 2001, 6, (1), 23-29. (In German) Acidic conditions of seepage and groundwater originating from open pit minings in Lusatia (Germany) are described using the neutralization potential, which is based on the concept of acidity. Acid formation and buffer reactions can be reduced to three elemental reactions: oxidation of pyrite/reduction of sulfate, dissolution of carbonate, and gypsum equilibrium. These reactions are combined in a genetic model in order to interpret the origin of mineral and acid contents of different groundwaters influenced by lignite mining. The statistical results of these calculations are summarized to calibrate parameters of a prognostic model. The method described here is used to prepare restoration measures.
164 Fuel and Energy Abstracts May 2002
02/01248 Ash quality of a beneficiated lignite from Ptolemais Basin, Northern Greece Vamvuka, D. et al. Energy FueL~, 2001, 15, (5), 1181-1185. A density separation method was used to reduce ash components, which form fireside deposits during coal combustion, as well as trace elements, in a Greek lignite. Standard techniques were applied to predict the slagging and fouling propensity of clean coal and to determine the trace elements concentration in this. Deposition tendencies were established through the use of empirical indexes for lignitic type ashes. Significant reductions in ash content (up to 60%) were achieved by dense liquid separation of the lignite. Coal cleaning diminished the slagging and fouling 16otential of the feed, reflecting some alterations in the chemical and mineralogy of the ash-forming components. The ash of beneficiated materials was richer in the basic oxides, while poorer in quartz. Also, the ash fusion temperatures (initial deformation and hemispherical) were significantly increased, though the contents of quartz and anhydrite remained high. Most trace elements were found to be associated with the mineral phase. Removal efficiency was low by the density separation method, but the environmental impact of these elements is anticipated to be negligible.
02/01249 Carbon reactivity in an oxygen plasma; a comparison with reactivity in molecular oxygen Cuesta, A. et al. Carbon, 200l, 39, (8), l 135-1146. Reactivity upon immersion in an oxygen plasma is studied in this paper on 46 different carbons and coals. Suitable parameters are chosen to characterize the plasma reactivity of these materials. The observed plasma reactivity trend is compared with the 02 reactivity trend shown by the same set of materials. Differences are discussed in terms of the influence of structural, chemical and textural factors upon carbon gasification in both media. To help discern these influences, multiple regression is applied to the factors derived from a principal components analysis. In contrast with 02 reactivity, oxygen plasma reactivity shows a more feeble dependence on structural factors and none on chemical factors. On the other hand, reactivity dependence from surface area appears to be stronger for the oxygen plasma than for 02. The above observations are interpreted as a corroboration of the Rideal-type mechanism proposed for the carbon--oxygen plasma reaction by Rosner and Allendorf.
02/01250 Characterization of surface properties of coals by film flotation. Sablik, J. and Wierzchowski, K. Zesz. Nauk. Politech. S/ask., Gorn., 2000, 246, (1), 451-466. (In Polish) Coal surface properties were studied using the film flotation technique. The critical wetting surface tension and surface energy heterogeneity depended on the coal rank. These values can be controlled by depositing chemical reagents on the coal surface, resulting in properties advantageous to the coal treatment method.
02/01251 Coal content of the Middle Carboniferous sediments of the Lvov-Volyn Basin Byk, S.I. Geol. Geokhim. Goryuch. Kopalin, 1999, 4, 48-52. (In Ukrainian) Drilling data on the coal concentration in the Middle Carboniferous rocks of the Lvov-Volyn Basin were studies. The main characteristics of coal concentration such as the thickness of the Middle Carboniferous sediments, the number of coal beds, the overall coal seam thickness and the ratio of general-to-industrial coal content were calculated and the directions of their changes throughout the area were analysed. The thickness of deposits increases in the west and northwest directions, and the increase rates are higher in the north and southwest parts of the basin than in its central part. The number of coal beds and interbeds increases from the east to the west, reaching 16-18 maximum North (Volyn field) and southwest (Tyagliv and Kariv fields) parts of the basin have the highest coal contents. A close relation between the thickness of the Middle Carboniferous rocks and the number of coal beds in them was established. The overall coal bed thickness is comparatively small (mainly less than two meters), and the trend in thickness changes is analogous to the changes in the abovementioned two parameters throughout the area. The ratio of coal availability is characterized by low values and homogeneity, almost throughout the whole area of the basin it ranges between 1-2, with the exception of the extreme west areas of the Volyn and Zabuzhian fields and the central, the most dipping parts of the Tyagliv and Kariv fields, where it increases up to 2.5-3.2. A conclusion was drawn that the most favourable conditions for accumulation of organic matter in the deposits of the Bashkir stage occurred to the north and southwest of the basin, and that improvement of such conditions and raise in rates of coal material accumulation happened in the direction of basin opening (that is to say, from the east to the west, in the direction of the Lublin Basin).