- Email: [email protected]
00035 Sapropel coals—properties and structure
01
Solid fuels (sources, winning, properties)
9aiooo24 Modification of hydrogen bonding interaction in coal with lithium iodide doping technique Komagai, H. et al. DGMK Tagungsber., 1997,9702, (Proceedings ICCS ‘97, Volume 1), 257-260. TGA and FT-IR spectroscopy were used to investigate the effects of LiI doping on H-bonding interaction in Loy Yang brown coal. The doping was found to enhance volatile evolution from the coal in a lower temperature range. IT-IR spectra showed that the duping replaces H bondings between OH groups with those between LiI and OH groups. These confirms that LiI interacts with OH groups and suppresses the original H-bonding interaction. In addition, the LiI duping suppresses the decomposition of OH groups and the formation of ether cross-linkage, resulting in an increase in the volatile matter yields. 98iOOO25 A new approach to coal structure Mastral, A. M. et al. DGMK Tagungsber., 1997, 9702, (Proceedings ICCS ‘97, Volume 1), 215-218. The approach involved calculating the average number of C atoms between cross-link points from solvent swelling measurements to study coal structure and its evolution in catalytic hydrogenation. It was found that at mild hydrogenation conditions, the solid residues have a structure with longer chains of aromatic clusters than in the parent coals. The porosimetry shows that there is a relationship between the increase of the skeletal density and chain length; the structure becomes more compact and ordered in the absence of low molecular weight or non-covalently bonded material. Organic petrology and organic geochemistry of 98lOOO26 selected lignites and bituminous coals from the Lena Basin (Yakutia, Russia) Herd, H. ef al. DGMK Tugungsber., 1997, 9702, (Proceedings ICCS ‘97, Volume 1), 27-30. For the first time, combined organic petrology and organic geochemical methods were used to study lignites and bituminous coals from several deposits of one of the world’s biggest coal basins, the Lena Basin, Yakutia (Russia). The aim of this study was to characterize these coals with regard to their technological potential and environmental impact depending on their petrographical and chemical properties. In addition, aspects of coal seam genesis and facies determination were addressed. Coal seam generation took place in the Viluy syneclise and the western fore-deep of the Verkhoyansk fold-belt mainly during the Upper Jurassic to the Lower Cretaceous periods. Most of the coals studied here are humic coals. Their rank, determined by petrological and chemical parameters, varies from lignite to high volatile bituminous coals. Rank was found to increase with depth and from western to eastern direction inside the Lena basin indicating the influence of the orogenesis close to the coal deposits. These coals are poor in ash and sulfur content and calorific values and results of the chemical analyses support their use for thermal conversion processes like combustion and power generation. Petrochemical basis for the rank (maturity) evalua98moO27 tion of Permian coals of the Ramagundam Coal Belt, Godavari Valley Coalfield, Andhra Pradesh Singh, G. P. J. Geol. Sot. India, 1997, 50, (4), 389-397. The paper states that Permian coals of Ramagundam coalfield are subbituminous to high volatile bituminous in rank on the basis of chemical and petrographical parameters. These coals are characterized as kerogen typeIII. Reflectance values suggest the maturation temperatures ranging from 46°C and 108°C and depth of burial of coal bearing horizons varies from I725 to 2175 m. 98100028 Petrographic characteristics of coals from outburst-susceptible beds Eremin, I. V. et al. Khim. Tverd. Topl., 1997, (2). 32-41. (In Russian) Vitrinite coals having tectonically deformed strata or separate stacks had highest susceptibility to sudden outbursts of coal and gas. Coal strata are transferred to a metastable state as a result of mechanical-chemical transformations due to tectonic forces. Polycondensation of carbon containing molecules. 98100029 Problems in the formation of fossil fuels and the carbon cycle in nature Rudenko, A. P. and Kulakova, I. I. Vestn. Mask. Univ., Ser. 2: Khim., 1996, 37, (6), 544-567. (In Russian) The paper provides scientific and theoretical generalization of studies on mechanisms of heterogeneous conversions of various carbon containing compounds, leading to the formation of condensation products. Possible sources of such products in nature, and also paths of their conversion during formation of different components of fossil fuels are considered. Macrokinetic factors, affecting the realization of natural polycondensation processes and formation of pools of various fossil fuels, are discussed. The principle factor is the function of open catalytic systems and the role of condensation products in the closing of two cycles (biogenic and abiogenic) in the carbon cycle in nature was shown. The energetics of these cycles is considered. The effect of temperature and time factors on natural polycondensation processes was evaluated. Examples of the formation of condensation products through conversion of various organic substances, including cellulose, and of mixture of CO with Ha were given.
4
Fuel and Energy Abstracts
January 1998
98looo30 Project for international classification of coals of low, medium, and high ranks Eremin, I. V. and Bronovets, T. M. Khim. Tverd. To@., 1997, (2), 3-12. (In Russian) A project for international classification of coals of low, medium, and high ranks based on geological-genetic characteristics, degree of coalification, petrographical composition, and degree of reduction is being developed. The classification is designed for evaluation of coal deposits during geological prospecting, mining, and industrial processing of coals. 98loo931 Properties and structure of gas coal and semicoking coal and their lithotypes Jasienko, S. ef al. DGMK Tagmtgsber., 1997, 9702, (Proceedings ICCS ‘Y7, Volume l), 71-74. An investigation of the properties and structure of coals indicating transitional structure in coalification, gas coal and semi-coking coal and their lithotypes vitrains and fusains. The paper presents the structural parameters and properties of coals and lithotypes characterizing their colloidal structure. Gas coal shows the structure which is transitional between an organosol and an organogel. Semi-coking coal shows the transitional structure between an organogel and xerogel. The transitional structure features are must evident in vitrains. Fusains can be classified as untypical xerogels. 9alooo32 Relation between characteristics of sulfurous coal of the northern Donets Basin and indexes of its hydrogenation Osipov, A. M. er al. Khim. Tverd. Topl., 1997, (2), 64-69. (In Russian) Long-flame sulfurous coal characteristics from the northern Donets Basin on a degree of conversion and yield of various fractions was studied during hydroliquefaction without catalysts. The greatest effect was witnessed with contents of S and Fe. 98looo33 Relation of physicochemical properties of coals to the chemical nature of the surface Zyla, M. et al. Karbo-Energochemical-Ekol., 1997, 42, (B), 107-108. (In Polish) The authors investigate the relationship between physico-chemical properties of coals of different rank and their surface chemical nature. Oxidation was performed in a liquid or a gaseous phase. The quantity and types of surface functional groups have been determined by HZ0 sorption, photoelectronic X-ray spectroscopy and IR absorption spectroscopy. A model of dual sorption was used to analyse sorption results. The role of hydrogen bonding in swelling of coal 9alooo34 Gao, J. et al. DGMK Tagungsber., 1997, 9702, (Proceedings ICCS ‘97, Volume 1), 163-166. The H bonding between coal and hydroxyl in coal has a significant effect on the swelling behaviour of coal. Since almost all the OH groups in coal are phenolic, p-fluorophenol (PFP) was used as a suitable model compound for coal hydroxyl. The swelling ratio of coal increases proportionally with the heat of H bonding formation between PFP and the corresponding solvent. Acid-treated lignite and alkali/acid-treated bituminous coal have higher swelling ratio in polar solvents than that of untreated coal due to the increase of OH group in coal by this treatment. The swelling ratio of lower rank coal is more sensitive than the higher rank coal to the heat of H bonding formation of coal-solvent. The results suggest that the H bonding between coal and solvent is the key factor in determining the swelling behaviour of coal in organic solvents. 98iooo35 Sapropel coals-properties and structure Machnikowska, H. and Jasienko, S. Karbo-Energochemical-Ekol., 1996, 41, (5), 180-185. (In Polish) Sapropel coal samples have been investigated. The Siberian coals are typical boghead coals and the Upper Silesian coal is a humus-sapropel coal. All coals produced high tar yield and low coke yield after coking at 900 “C. 98lO9036 The softening mechanisms of heat-treated caking coals Yoshida, T. et al. DGMK Tagungsber., 1997, 9703, (Proceedings ICCS ‘97, Volume 2), 809-812. At a heating rate of 3”C/min, caking and non-caking coals were heat-treated in an autoclave under nitrogen, and then quenched to room temperature. The coals were extracted with a carbon disulfide-h’-methyl-2-pyrrolidinone (CSz-NMP) mixed solvent at room temperature. Higher extraction yields were obtained with the caking coals and their extracts were rich in heavier components. For the heat-treated coals, the extraction yields were maximal in the softening temperature ranges. The maximum fluidities of coals were found to be closely related to their maximum extraction yields. 98100037 The structural changes of different rank coals due to impregnation by alkali metal hydroxides Zubova, T. I. and Knabarova, T. V. DGMK Togungsber., 1997, 9702, (Proceedings ICCS ‘97, Volume l), 139-142. The way in which the structure of different rank coals was affected by intercalation by alkalis MOH (M = Li+, Na+, Kf, Rb+, Cs+) was examined. The impregnation (soaking coal m alkali aqueous solutions at room temperature with subsequent drying) converts coal in a new substance. Previously, tests proved brown coal’s alkali treatment with
Solid fuels (sources, winning, properties)
9aiooo24 Modification of hydrogen bonding interaction in coal with lithium iodide doping technique Komagai, H. et al. DGMK Tagungsber., 1997,9702, (Proceedings ICCS ‘97, Volume 1), 257-260. TGA and FT-IR spectroscopy were used to investigate the effects of LiI doping on H-bonding interaction in Loy Yang brown coal. The doping was found to enhance volatile evolution from the coal in a lower temperature range. IT-IR spectra showed that the duping replaces H bondings between OH groups with those between LiI and OH groups. These confirms that LiI interacts with OH groups and suppresses the original H-bonding interaction. In addition, the LiI duping suppresses the decomposition of OH groups and the formation of ether cross-linkage, resulting in an increase in the volatile matter yields. 98iOOO25 A new approach to coal structure Mastral, A. M. et al. DGMK Tagungsber., 1997, 9702, (Proceedings ICCS ‘97, Volume 1), 215-218. The approach involved calculating the average number of C atoms between cross-link points from solvent swelling measurements to study coal structure and its evolution in catalytic hydrogenation. It was found that at mild hydrogenation conditions, the solid residues have a structure with longer chains of aromatic clusters than in the parent coals. The porosimetry shows that there is a relationship between the increase of the skeletal density and chain length; the structure becomes more compact and ordered in the absence of low molecular weight or non-covalently bonded material. Organic petrology and organic geochemistry of 98lOOO26 selected lignites and bituminous coals from the Lena Basin (Yakutia, Russia) Herd, H. ef al. DGMK Tugungsber., 1997, 9702, (Proceedings ICCS ‘97, Volume 1), 27-30. For the first time, combined organic petrology and organic geochemical methods were used to study lignites and bituminous coals from several deposits of one of the world’s biggest coal basins, the Lena Basin, Yakutia (Russia). The aim of this study was to characterize these coals with regard to their technological potential and environmental impact depending on their petrographical and chemical properties. In addition, aspects of coal seam genesis and facies determination were addressed. Coal seam generation took place in the Viluy syneclise and the western fore-deep of the Verkhoyansk fold-belt mainly during the Upper Jurassic to the Lower Cretaceous periods. Most of the coals studied here are humic coals. Their rank, determined by petrological and chemical parameters, varies from lignite to high volatile bituminous coals. Rank was found to increase with depth and from western to eastern direction inside the Lena basin indicating the influence of the orogenesis close to the coal deposits. These coals are poor in ash and sulfur content and calorific values and results of the chemical analyses support their use for thermal conversion processes like combustion and power generation. Petrochemical basis for the rank (maturity) evalua98moO27 tion of Permian coals of the Ramagundam Coal Belt, Godavari Valley Coalfield, Andhra Pradesh Singh, G. P. J. Geol. Sot. India, 1997, 50, (4), 389-397. The paper states that Permian coals of Ramagundam coalfield are subbituminous to high volatile bituminous in rank on the basis of chemical and petrographical parameters. These coals are characterized as kerogen typeIII. Reflectance values suggest the maturation temperatures ranging from 46°C and 108°C and depth of burial of coal bearing horizons varies from I725 to 2175 m. 98100028 Petrographic characteristics of coals from outburst-susceptible beds Eremin, I. V. et al. Khim. Tverd. Topl., 1997, (2). 32-41. (In Russian) Vitrinite coals having tectonically deformed strata or separate stacks had highest susceptibility to sudden outbursts of coal and gas. Coal strata are transferred to a metastable state as a result of mechanical-chemical transformations due to tectonic forces. Polycondensation of carbon containing molecules. 98100029 Problems in the formation of fossil fuels and the carbon cycle in nature Rudenko, A. P. and Kulakova, I. I. Vestn. Mask. Univ., Ser. 2: Khim., 1996, 37, (6), 544-567. (In Russian) The paper provides scientific and theoretical generalization of studies on mechanisms of heterogeneous conversions of various carbon containing compounds, leading to the formation of condensation products. Possible sources of such products in nature, and also paths of their conversion during formation of different components of fossil fuels are considered. Macrokinetic factors, affecting the realization of natural polycondensation processes and formation of pools of various fossil fuels, are discussed. The principle factor is the function of open catalytic systems and the role of condensation products in the closing of two cycles (biogenic and abiogenic) in the carbon cycle in nature was shown. The energetics of these cycles is considered. The effect of temperature and time factors on natural polycondensation processes was evaluated. Examples of the formation of condensation products through conversion of various organic substances, including cellulose, and of mixture of CO with Ha were given.
4
Fuel and Energy Abstracts
January 1998
98looo30 Project for international classification of coals of low, medium, and high ranks Eremin, I. V. and Bronovets, T. M. Khim. Tverd. To@., 1997, (2), 3-12. (In Russian) A project for international classification of coals of low, medium, and high ranks based on geological-genetic characteristics, degree of coalification, petrographical composition, and degree of reduction is being developed. The classification is designed for evaluation of coal deposits during geological prospecting, mining, and industrial processing of coals. 98loo931 Properties and structure of gas coal and semicoking coal and their lithotypes Jasienko, S. ef al. DGMK Tagmtgsber., 1997, 9702, (Proceedings ICCS ‘Y7, Volume l), 71-74. An investigation of the properties and structure of coals indicating transitional structure in coalification, gas coal and semi-coking coal and their lithotypes vitrains and fusains. The paper presents the structural parameters and properties of coals and lithotypes characterizing their colloidal structure. Gas coal shows the structure which is transitional between an organosol and an organogel. Semi-coking coal shows the transitional structure between an organogel and xerogel. The transitional structure features are must evident in vitrains. Fusains can be classified as untypical xerogels. 9alooo32 Relation between characteristics of sulfurous coal of the northern Donets Basin and indexes of its hydrogenation Osipov, A. M. er al. Khim. Tverd. Topl., 1997, (2), 64-69. (In Russian) Long-flame sulfurous coal characteristics from the northern Donets Basin on a degree of conversion and yield of various fractions was studied during hydroliquefaction without catalysts. The greatest effect was witnessed with contents of S and Fe. 98looo33 Relation of physicochemical properties of coals to the chemical nature of the surface Zyla, M. et al. Karbo-Energochemical-Ekol., 1997, 42, (B), 107-108. (In Polish) The authors investigate the relationship between physico-chemical properties of coals of different rank and their surface chemical nature. Oxidation was performed in a liquid or a gaseous phase. The quantity and types of surface functional groups have been determined by HZ0 sorption, photoelectronic X-ray spectroscopy and IR absorption spectroscopy. A model of dual sorption was used to analyse sorption results. The role of hydrogen bonding in swelling of coal 9alooo34 Gao, J. et al. DGMK Tagungsber., 1997, 9702, (Proceedings ICCS ‘97, Volume 1), 163-166. The H bonding between coal and hydroxyl in coal has a significant effect on the swelling behaviour of coal. Since almost all the OH groups in coal are phenolic, p-fluorophenol (PFP) was used as a suitable model compound for coal hydroxyl. The swelling ratio of coal increases proportionally with the heat of H bonding formation between PFP and the corresponding solvent. Acid-treated lignite and alkali/acid-treated bituminous coal have higher swelling ratio in polar solvents than that of untreated coal due to the increase of OH group in coal by this treatment. The swelling ratio of lower rank coal is more sensitive than the higher rank coal to the heat of H bonding formation of coal-solvent. The results suggest that the H bonding between coal and solvent is the key factor in determining the swelling behaviour of coal in organic solvents. 98iooo35 Sapropel coals-properties and structure Machnikowska, H. and Jasienko, S. Karbo-Energochemical-Ekol., 1996, 41, (5), 180-185. (In Polish) Sapropel coal samples have been investigated. The Siberian coals are typical boghead coals and the Upper Silesian coal is a humus-sapropel coal. All coals produced high tar yield and low coke yield after coking at 900 “C. 98lO9036 The softening mechanisms of heat-treated caking coals Yoshida, T. et al. DGMK Tagungsber., 1997, 9703, (Proceedings ICCS ‘97, Volume 2), 809-812. At a heating rate of 3”C/min, caking and non-caking coals were heat-treated in an autoclave under nitrogen, and then quenched to room temperature. The coals were extracted with a carbon disulfide-h’-methyl-2-pyrrolidinone (CSz-NMP) mixed solvent at room temperature. Higher extraction yields were obtained with the caking coals and their extracts were rich in heavier components. For the heat-treated coals, the extraction yields were maximal in the softening temperature ranges. The maximum fluidities of coals were found to be closely related to their maximum extraction yields. 98100037 The structural changes of different rank coals due to impregnation by alkali metal hydroxides Zubova, T. I. and Knabarova, T. V. DGMK Togungsber., 1997, 9702, (Proceedings ICCS ‘97, Volume l), 139-142. The way in which the structure of different rank coals was affected by intercalation by alkalis MOH (M = Li+, Na+, Kf, Rb+, Cs+) was examined. The impregnation (soaking coal m alkali aqueous solutions at room temperature with subsequent drying) converts coal in a new substance. Previously, tests proved brown coal’s alkali treatment with