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00607 Petrologic and geochemical characteristics of ‘barkinite’ from the Dahe mine, Guizhou Province, China
01
Solid
01
fuels
(sources,
winning,
SOLID
properties) mass spectrometry (GC-MS). The presence of Cz4-Czs diaromatic compounds, not previously reported in coals, suggests that photosynthetic green sulfur bacteria may have made an input of organic matter to these coals. The unsaturated linear alkenylbenzenes and isoprenyl (Cis and &a) alkylbenzene skeletons are also described for the first time in the soluble fraction of geological samples.
FUELS
Sources,winning, properties 04/00599 Coal characterisation petrography
by automated
04/00604 Notes on the marginal In coal beds coal
O’Brien, G. et al. Fuel, 2003, 82, (9), 1067-1073. Automated imaging techniques were refined to characterize the rank and maceral composition of coals by a full maceral reflectogram of polished coal grain mounts. Precision was improved by processing individual grains in each image separately and correcting within the software for the topography that occurs between the different macerals and minerals in the grains. Maceral group proportions and vitrinite reflectance information extracted from these reflectograms compared well with manual results for a comprehensive suite of Australian coals varying in rank from a mean vitrinite reflectance of 0.48-2.13%. A parameter that combines rank and type calculated from the reflectograms correlated strongly with chemical properties determined by ultimate and proximate analyses. For a limited number of samples, for which coking tests had been performed, this parameter also correlated with estimated coking performance.
04/00600 Coal spontaneous programmed temperature
combustion
characteristics
at
Xie, Z. el al. Beijing Keji Dame Xuebao, 2003, 25, (I), 12-14. (In Chinese) The characteristics of coal spontaneous combustion were investigated through programmed temperature experiment and the concentration of CO and COz for coal with various sizes was measured at different temperatures. The selection of index gases was discussed. The law of concentration change for CO, COz and the relation of consuming oxygen velocity to coal temperature and size were analysed. The smaller the coal size and the higher the temperature, the more intense the reaction of coal and oxygen. The results can direct the prevention and treatment of fire in mines.
04/00601
Combustion
characteristics
of power coal
Zheng, M. and He, X. Huagong Xuebao, 2003, 54, (3), 374-378. (In Chinese) Combustion reaction is the most important method of coal conversion, coal’s combustion parameter plays an important role in evaluating its ecological and economic indicators. The combustion characteristics are studied in this paper on six types of different rank power coals by thermogravimetric and Fourier transform IR spectrometry technique, respectively. Each characteristic temperature and the temperature at which these gases, such as CO, COz and HzO, are released, become smaller with the decrease of the coal rank, contrarily weight loss of lower rank coal sample between each characteristic temperature increases. CO is generated at the lower temperature while CO2 is mainly generated at a higher temperature. Both the variation of activation energy and the reaction order pass a maximum as the temperature increases in the combustion process. All the above observations indicate that lower rank coal is easier to combust than higher rank coal.
04/00602 Comparative study of the quality from the Zlbo coal field
of some coals
Liu, G. et al. Energy, 2003, 28, (lo), 9699978. The basic chemical composition of coal and ash is an important but insufficient characteristic for the reliable explanation of coal properties. The modes of occurrence of the elements, their origin and concentration in coal, as well as their behaviour during the coalification process, are also very important parameters for coal quality. The characteristics noted above can be used as a guide for the prediction of some properties and behaviour of coal and its products during use. Sapropelic coal was formed from algae and herbs under special environments. The matter that formed sapropelic coal is obviously different from that of humic coal. There are great differences in geochemical characterization between these types of coal. On the basis of identified samples of paragenetic sapropelic coal and humic coal from hole drilling, the moisture, sulphur content, heat value, ash yield and ash composition in these two types of coal have been studied using the comparative method.
04/00603
New aromatic
biomarkers
in sulfur-rich
coal
Gorchs, R. et al. Organic Geochemistry, 2003, 34, (12), 1627-1633. A molecular study of linear, branched and isoprenyl alkylbenzene skeletons and alkenylbenzenes in the soluble fraction extracted from sulfur-rich Utrillas coal was carried out using gas chromatography82
Fuel
and
Energy
Abstracts
March 2004
a
enrichment
of Germanium
Yudovich, Y. E. International Journal of Coal Geology, 2003, 56, (3-4), 223-232. Germanium distribution in coal has long been a topic of interest. The enrichment of Ge near margins of coals, including the margins of partings within the coal, has been noted in many coals from numerous coalfields throughout the world. In this paper, a summary of literature on Ge geochemistry on the upper and lower margins of coal seams, with special emphasis on the literature of Russia, and the former Soviet Union, and Japan, is presented.
Wji605
Organic
affinity of silver in subbituminous
Assam
Baruah, M. K. et al. Fuel, 2003, 82, (lo), 1291-1293. Silver has been identified for the first time in high sulfur coals of Assam, India. Its total concentration varies from 55-60 microgram/g and dominantly associated with the organic fraction (281.8%) in nonexchangeable form. Knowledge gained from this study will be helpful to predict geochemical principles involved in association of silver with geological substrate.
04/00606 Oxidation behavior and caking property under the atmosphere at low oxygen concentration
of coal
Ota, H. et al. ISIJ International, 2003, 43, (3), 331-337. Eight coals ranging from bituminous coal to brown coal were oxidized in a thermo-balance or a fixed bed reactor using 5 ~01% of oxygen at 100-380°C for lo-400 min. The effects of coal particle size, coal rank, oxidation temperature and oxygen concentration on the oxidation behaviour of coal were investigated. The caking property, FT-IR spectrum and pyrolysis behaviour of sample oxidized were measured. The oxidation, behaviour strongly depended on the coal rank. The oxidation reaction of highly caking coal was controlled by the rate of internal gaseous diffusion. The caking property of bituminous coal decreases by the oxidation in the oxidative atmosphere of low oxygen concentration of 5 vol%, which corresponds to that in a flue gas. The aliphatic C-H groups in highly caking coals are easily oxidized during oxidation and remained in coal structure as relatively stable forms. The differences in chemical structure and caking property between the exterior part and the central part of oxidized coal particle were investigated. In the case of highly caking coal, the chemical structure and some properties of oxidized coal depend on the position of the coal particle because the mild oxidation reaction of coal proceeds from the exterior part of coal particle.
04lOO607 ‘barkinite’
Petrologic and geochemical characteristics of from the Dahe mine, Guirhou Province, China
Sun, Y. International Journal of Coal Geology, 2003, 56, (3-4), 269-276. Although ‘barkinite’ has long been studied by many geologists, its geochemical characteristics and environment of deposition are still not known in detail. In order to study the petrography and geochemical characteristics of ‘barkinite’, coal samples from two Permian coal seams were taken from the Dahe mine, Guizhou Province. The samples were separated into maceral fractions, and then analysed by microscopical, isotopic, Rock-Eval, and geochemical methods. The microscopical results indicate that ‘barkinite’ occurs as four main types. According to their relationship to other maceral groups, ‘barkinite’ is ostensibly formed under variably dry-wet or oxidizing-reducing conditions. The extract yield, isotope data and Rock-Eva1 values of ‘barkinite’ are different from other macerals. Microscopical and geochemical results indicate that ‘barkinite’ forms part of the liptinite group.
04/00608 selective
Recovery flocculation
of fine coal from waste streams process
by the
Parekh, B. K. and Chen, 2. Minerals & Metallurgical Processing, 2003, 20, (1) 21-25. In the United States, a significant amount of fine, -150~pm (-lOOmesh) coal is rejected because of the unavailability of an economical recovery process. In the last decade, coal companies have realized the financial and environmental potential for recovering the fine clean coal from waste streams. The main objective is to investigate the applicability of selective flocculation for recovering clean coal from waste stream samples obtained from a coal preparation plant owned by the Peabody Coal Co. A 1 kg/ton dispersant and 2 g/ton flucculant were effective in recovering a clean coal product containing 14% ash with a 90% combustible recovery. Three-stage cleaning of the flocculated coal provided a lo%-ash clean coal. A Hydrofloat separator was effective in
Solid
01
fuels
(sources,
winning,
SOLID
properties) mass spectrometry (GC-MS). The presence of Cz4-Czs diaromatic compounds, not previously reported in coals, suggests that photosynthetic green sulfur bacteria may have made an input of organic matter to these coals. The unsaturated linear alkenylbenzenes and isoprenyl (Cis and &a) alkylbenzene skeletons are also described for the first time in the soluble fraction of geological samples.
FUELS
Sources,winning, properties 04/00599 Coal characterisation petrography
by automated
04/00604 Notes on the marginal In coal beds coal
O’Brien, G. et al. Fuel, 2003, 82, (9), 1067-1073. Automated imaging techniques were refined to characterize the rank and maceral composition of coals by a full maceral reflectogram of polished coal grain mounts. Precision was improved by processing individual grains in each image separately and correcting within the software for the topography that occurs between the different macerals and minerals in the grains. Maceral group proportions and vitrinite reflectance information extracted from these reflectograms compared well with manual results for a comprehensive suite of Australian coals varying in rank from a mean vitrinite reflectance of 0.48-2.13%. A parameter that combines rank and type calculated from the reflectograms correlated strongly with chemical properties determined by ultimate and proximate analyses. For a limited number of samples, for which coking tests had been performed, this parameter also correlated with estimated coking performance.
04/00600 Coal spontaneous programmed temperature
combustion
characteristics
at
Xie, Z. el al. Beijing Keji Dame Xuebao, 2003, 25, (I), 12-14. (In Chinese) The characteristics of coal spontaneous combustion were investigated through programmed temperature experiment and the concentration of CO and COz for coal with various sizes was measured at different temperatures. The selection of index gases was discussed. The law of concentration change for CO, COz and the relation of consuming oxygen velocity to coal temperature and size were analysed. The smaller the coal size and the higher the temperature, the more intense the reaction of coal and oxygen. The results can direct the prevention and treatment of fire in mines.
04/00601
Combustion
characteristics
of power coal
Zheng, M. and He, X. Huagong Xuebao, 2003, 54, (3), 374-378. (In Chinese) Combustion reaction is the most important method of coal conversion, coal’s combustion parameter plays an important role in evaluating its ecological and economic indicators. The combustion characteristics are studied in this paper on six types of different rank power coals by thermogravimetric and Fourier transform IR spectrometry technique, respectively. Each characteristic temperature and the temperature at which these gases, such as CO, COz and HzO, are released, become smaller with the decrease of the coal rank, contrarily weight loss of lower rank coal sample between each characteristic temperature increases. CO is generated at the lower temperature while CO2 is mainly generated at a higher temperature. Both the variation of activation energy and the reaction order pass a maximum as the temperature increases in the combustion process. All the above observations indicate that lower rank coal is easier to combust than higher rank coal.
04/00602 Comparative study of the quality from the Zlbo coal field
of some coals
Liu, G. et al. Energy, 2003, 28, (lo), 9699978. The basic chemical composition of coal and ash is an important but insufficient characteristic for the reliable explanation of coal properties. The modes of occurrence of the elements, their origin and concentration in coal, as well as their behaviour during the coalification process, are also very important parameters for coal quality. The characteristics noted above can be used as a guide for the prediction of some properties and behaviour of coal and its products during use. Sapropelic coal was formed from algae and herbs under special environments. The matter that formed sapropelic coal is obviously different from that of humic coal. There are great differences in geochemical characterization between these types of coal. On the basis of identified samples of paragenetic sapropelic coal and humic coal from hole drilling, the moisture, sulphur content, heat value, ash yield and ash composition in these two types of coal have been studied using the comparative method.
04/00603
New aromatic
biomarkers
in sulfur-rich
coal
Gorchs, R. et al. Organic Geochemistry, 2003, 34, (12), 1627-1633. A molecular study of linear, branched and isoprenyl alkylbenzene skeletons and alkenylbenzenes in the soluble fraction extracted from sulfur-rich Utrillas coal was carried out using gas chromatography82
Fuel
and
Energy
Abstracts
March 2004
a
enrichment
of Germanium
Yudovich, Y. E. International Journal of Coal Geology, 2003, 56, (3-4), 223-232. Germanium distribution in coal has long been a topic of interest. The enrichment of Ge near margins of coals, including the margins of partings within the coal, has been noted in many coals from numerous coalfields throughout the world. In this paper, a summary of literature on Ge geochemistry on the upper and lower margins of coal seams, with special emphasis on the literature of Russia, and the former Soviet Union, and Japan, is presented.
Wji605
Organic
affinity of silver in subbituminous
Assam
Baruah, M. K. et al. Fuel, 2003, 82, (lo), 1291-1293. Silver has been identified for the first time in high sulfur coals of Assam, India. Its total concentration varies from 55-60 microgram/g and dominantly associated with the organic fraction (281.8%) in nonexchangeable form. Knowledge gained from this study will be helpful to predict geochemical principles involved in association of silver with geological substrate.
04/00606 Oxidation behavior and caking property under the atmosphere at low oxygen concentration
of coal
Ota, H. et al. ISIJ International, 2003, 43, (3), 331-337. Eight coals ranging from bituminous coal to brown coal were oxidized in a thermo-balance or a fixed bed reactor using 5 ~01% of oxygen at 100-380°C for lo-400 min. The effects of coal particle size, coal rank, oxidation temperature and oxygen concentration on the oxidation behaviour of coal were investigated. The caking property, FT-IR spectrum and pyrolysis behaviour of sample oxidized were measured. The oxidation, behaviour strongly depended on the coal rank. The oxidation reaction of highly caking coal was controlled by the rate of internal gaseous diffusion. The caking property of bituminous coal decreases by the oxidation in the oxidative atmosphere of low oxygen concentration of 5 vol%, which corresponds to that in a flue gas. The aliphatic C-H groups in highly caking coals are easily oxidized during oxidation and remained in coal structure as relatively stable forms. The differences in chemical structure and caking property between the exterior part and the central part of oxidized coal particle were investigated. In the case of highly caking coal, the chemical structure and some properties of oxidized coal depend on the position of the coal particle because the mild oxidation reaction of coal proceeds from the exterior part of coal particle.
04lOO607 ‘barkinite’
Petrologic and geochemical characteristics of from the Dahe mine, Guirhou Province, China
Sun, Y. International Journal of Coal Geology, 2003, 56, (3-4), 269-276. Although ‘barkinite’ has long been studied by many geologists, its geochemical characteristics and environment of deposition are still not known in detail. In order to study the petrography and geochemical characteristics of ‘barkinite’, coal samples from two Permian coal seams were taken from the Dahe mine, Guizhou Province. The samples were separated into maceral fractions, and then analysed by microscopical, isotopic, Rock-Eval, and geochemical methods. The microscopical results indicate that ‘barkinite’ occurs as four main types. According to their relationship to other maceral groups, ‘barkinite’ is ostensibly formed under variably dry-wet or oxidizing-reducing conditions. The extract yield, isotope data and Rock-Eva1 values of ‘barkinite’ are different from other macerals. Microscopical and geochemical results indicate that ‘barkinite’ forms part of the liptinite group.
04/00608 selective
Recovery flocculation
of fine coal from waste streams process
by the
Parekh, B. K. and Chen, 2. Minerals & Metallurgical Processing, 2003, 20, (1) 21-25. In the United States, a significant amount of fine, -150~pm (-lOOmesh) coal is rejected because of the unavailability of an economical recovery process. In the last decade, coal companies have realized the financial and environmental potential for recovering the fine clean coal from waste streams. The main objective is to investigate the applicability of selective flocculation for recovering clean coal from waste stream samples obtained from a coal preparation plant owned by the Peabody Coal Co. A 1 kg/ton dispersant and 2 g/ton flucculant were effective in recovering a clean coal product containing 14% ash with a 90% combustible recovery. Three-stage cleaning of the flocculated coal provided a lo%-ash clean coal. A Hydrofloat separator was effective in