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00135 Mixing-heating apparatus for manufacture of coal briquets
01
Solid fuels (derived solid fuels)
98100136 Mixing-heating apparatus for manufacture of coal briquets Omizo, K. et al. Jpn. Kokai Tokkyo Koho JP 09,157,669 [97,157,669] (Cl. CIOLSIIO), 17 Jun 1997, Appl. 951317,843, 6 Dee 1995, 6 pp. (In Japanese) Coal briquettes are manufactured with this mixing-heating apparatus. It includes a spiral vane positioned on the outer surface of rotation shaft for mixing raw materials along guideways of axial direction and a heating method for heating the raw materials. Heating is done inside the rotation shaft by passing the heating medium through a hollow pipe and injection nozzles installed on the rotation shaft. The injection nozzles of the heating medium are adjacently fitted along the axial direction of non-guiding surface of the vane and the direction of nozzle injection is positioned towards the moving direction of the shaft. Numerical analysis of macrocrack formation beha98100136 vior in lump coke Sato, H. et al. Fuel, 1997, 76, (9), 879-885. Macrocrack formation and deformation behaviour in lump coke was investigated by thermal stress analysis. This behaviour strongly influences heat and mass transfer in a coke oven chamber. The dilatation of the plastic layer, heating-rate dependence of thermophysical and mechanical properties of the coal/coke, creep in the plastic and semi-coke layers, macrocrack propagation and radiative heat transfer within the macrocrack were considered in an analysis model. The estimated stress intensity factor, Kt, at the macrocrack tip compared with the plane strain fracture toughness, Ku-, through unsteady-state calculation facilitated the determination of macrocrack propagation. Calculated results from crack formation and deformation behaviour of lump coke were in good agreement with experimental observations using a laboratory-scale oven chamber. The analysis model could also predict microcrack formation within lump coke normal to the heated wall and the coke surface close to the heated wall. Percolation leaching of uranium-bearing coal ash 98lOOl37 calcined briquet Xie, F. and Ma, M. Youkuangye, 1997, 16, (I), 19-23. (In Chinese) The paper presents results from percolation leaching experiments of uranium-bearing calcined coal ash briquettes. The influence of technological parameters on uranium leaching rate and the adaptability of mechanical strength of the briquette to percolation leaching operation are discussed. Under optimum conditions, uranium leaching is 97.8% complete, a level comparable to agitation leaching. It is found that the mechanical strength of the calcined briquette meets the needs of percolation leaching operation. 98100138 The place of coking in coal processing Zielinski, H. K&o-Energochemical-Ekol., 1996, 41, (1) 3-7. (In Polish) Coal remains as the main energy source and methanol synthesis may be the chance for its mass processing. World coal use for coking industry will be 0.5 Gtons/yr. Coke production in Poland has decreased from 20 to 11 Mtons/yr and it is assumed it will increase to 13-14 Mtonsiyr after modernization. Another question for the coking industry is to start cokelike formed fuel production. 98/00139 Polymerization of anthracene-oil by thermal treatment in the presence of aluminum trichloride Fernandez, A. L. ef al. DGMK Tagungsber., 1997, 9703, (Proceedings ICCS ‘97, Volume 2), 901-904. Anhydrous AICIs in several concentrations was used in the polymerization of commercial anthracene oil in the range 250-325°C. The kinetics of the process and the degree of conversion of the anthracene oil were monitored by thermogravimetric analysis and the evolution of the concentration of the main anthracene oil components was monitored by GC. At 900°C the coke obtained from the pitches were characterized by their optical texture and their reactivity with air at 1000°C.
98100140 Preparation of pitches by coal-tar air-blowing Prada, V. et al. DGMK Tagungsber., 1997, 9703, (Proceedings ICCS ‘97, Volume 2), 893-896. At temperatures of 275 and 300°C three coal tar pitches were prepared by air-blowing of tar under gas pressure. The resulting pitches were characterized by their physical and chemical properties as well as their pyrolysis behaviour. Pitches obtained by thermogravimetric analysis at temperatures of 900 and 1000°C yielded cokes with an optical texture from flow domains to mosaics, depending on the temperature and duration of treatment. 98lOO141 The process of utilization of organic waste by method of hard coal coking Zmuda, W. et al. DGMK Tagungsber., 1997, 9703, (Proceedings ICCS ‘97, Volume 2), 853-856. Various organic wastes were mixed with coal tar pitch or petroleum asphalt and solid carbonaceous waste material. The resulting products were granulated and blended with coal for the coking process. The paper describes properties of granulates with different composition as well as the properties of the resulting cokes.
12
Fuel and Energy Abstracts
January 1998
98100142 Production of brown coal-based fireplace fuel Haege, K. et al. Ger. DE 19,614,715 (Cl. ClOLS/O2), 10 Jul 1997, Appl. 19,614,715, 13 Apr 1996, 3 pp. (In German) Mixing of 65-75 weight parts brown-coal fines with 25-35 weight parts molten paraffin wax at a temperature lower than the wax melting point produces this fuel. Alternatively, 65-75 weight parts brown-coal dust mixed with 25-35 weight parts molten paraffin wax at a temperature equal or higher than the wax melting point can be used. The resulting mixture is pressed at
98100143 Relations between degree of graphitization and galvanomagnetic properties of pyrolytic carbons and cokes Iwashita, N. et al. Carbon, 1997, 35, (8), 1073-1077. The paper studies the relationships between degree of graphitization (P,) and galvanomagnetic properties [maximum magnetoresistance (AA/A)maximum Hall coefficient RH and electrical resistivity Q] for pyrolytic carbons and cokes treated at different temperatures. With increasing heat treatment temperature, sign changes from negative to positive in (AQ/Q),,,., and from positive to negative in RH took place at Pi 0.5, irrespective of the specimen. Such a phenomenon implies that electronic conduction in these specimens changes from a one-carrier type to a two-carrier type when the threedimensional graphitic stacking order becomes predominant in the volume fraction. Galvanomagnetic parameters as a function of Pi depend considerably on the texture of the C materials. However, a positive value of (AQIQ)m.,x was observed as a unique function of the crystallite size of the hexagonal C layers, independent of the specimen. The degree of orientation of the hexagonal layers strongly affects the absolute value of RH. 98100144 Separation of sulfur from metallurgical coke by temperature treatment up to 2400” Legin-Kolar, M. and Radenovic, A. DGMK Tagungsber., 1997, 9703, (Proceedings ICCS ‘97, Volume 2) 757-760. Both before and after thermal treatment of various coke samples at 1200, 1600, 2000, and 2400°C the sulfur content was analysed. The samples were heated at the rates of 10 and 30”Cimin for 2 and 4 h. The cokes analysed were manufactured both with and without additives. In the case of the coke produced from the cooking coal and coal tar pitch as additive, it was found that the separation following high temperature treatment was the most efficacious. In the cokes that passed through the cooking process, only some of the S compounds present in the cooking coal were identified. After heating up to 1600°C all of the inorganic sulfur was separated from the cokes produced with the additives. The sulfur determined in the range 1600-2400°C was organic in origin.
98100145 Studies on generation of excessive coking pressure. 1. Semicoke contraction versus thermoplastic properties of coals Alvarez, R. er al. Energy Fuels, 1997, 11, (5). 978-981. Forty-two coals were studied regarding their thermoplastic properties and the volume contraction/expansion observed for their semi-coke layers. The objective was to attempt to find an interrelation between coal thermoplasticity and semi-coke contraction. The results, which may lend support to one or both accepted views of the mechanism of generation of excessive coking pressure by some coals, may also have application on laboratory testing methods for coking coals. The Gieseler thermoplastic properties and the contraction values of carbonized coals by the Koppers-INCAR tests were measured. In general, rather diffused or no relationships were found between the contraction on one hand and the thermoplastic properties on the other. The above two views may be synthesised on the condition that causative links could be found between more specific characteristics of thermal decomposition during coal plastic state and contraction of semicoke layer.
98100146 Studies on generation of excessive coking pressure. 2. Field ionization mass spectrometry of coals showing different contraction during carbonization Marzec, A. et al. Energy Fuels, 1997, 11, (5) 982-986. Various coals of different volume contraction/expansion and ‘wall’ pressures were heated and their decomposition products were analysed by pyrolysis field ionization mass spectrometry (Py-FIMS). The experiments aimed to characterize features of thermal decomposition of the coals that influence their contraction as well as their ‘wall’ pressure development during coking. A relationship was observed; Py-FIMS results indicated that the contraction values depend on (1) yields of thermal degradation products generated in coals upon their heating to the resolidification temperature and (2) individual composition of the thermal decomposition products. Coals showed high contraction values and low wall pressures when their yields of thermal degradation products were > 14 wt% and also when high-alkylated aromatics predominated over low-alkylated aromatics in the products. The yield and composition of thermal degradation products generated in the plastic layer influenced not only the contraction of the semi-coke layer but also the permeability for gaseous and vapour products.
Solid fuels (derived solid fuels)
98100136 Mixing-heating apparatus for manufacture of coal briquets Omizo, K. et al. Jpn. Kokai Tokkyo Koho JP 09,157,669 [97,157,669] (Cl. CIOLSIIO), 17 Jun 1997, Appl. 951317,843, 6 Dee 1995, 6 pp. (In Japanese) Coal briquettes are manufactured with this mixing-heating apparatus. It includes a spiral vane positioned on the outer surface of rotation shaft for mixing raw materials along guideways of axial direction and a heating method for heating the raw materials. Heating is done inside the rotation shaft by passing the heating medium through a hollow pipe and injection nozzles installed on the rotation shaft. The injection nozzles of the heating medium are adjacently fitted along the axial direction of non-guiding surface of the vane and the direction of nozzle injection is positioned towards the moving direction of the shaft. Numerical analysis of macrocrack formation beha98100136 vior in lump coke Sato, H. et al. Fuel, 1997, 76, (9), 879-885. Macrocrack formation and deformation behaviour in lump coke was investigated by thermal stress analysis. This behaviour strongly influences heat and mass transfer in a coke oven chamber. The dilatation of the plastic layer, heating-rate dependence of thermophysical and mechanical properties of the coal/coke, creep in the plastic and semi-coke layers, macrocrack propagation and radiative heat transfer within the macrocrack were considered in an analysis model. The estimated stress intensity factor, Kt, at the macrocrack tip compared with the plane strain fracture toughness, Ku-, through unsteady-state calculation facilitated the determination of macrocrack propagation. Calculated results from crack formation and deformation behaviour of lump coke were in good agreement with experimental observations using a laboratory-scale oven chamber. The analysis model could also predict microcrack formation within lump coke normal to the heated wall and the coke surface close to the heated wall. Percolation leaching of uranium-bearing coal ash 98lOOl37 calcined briquet Xie, F. and Ma, M. Youkuangye, 1997, 16, (I), 19-23. (In Chinese) The paper presents results from percolation leaching experiments of uranium-bearing calcined coal ash briquettes. The influence of technological parameters on uranium leaching rate and the adaptability of mechanical strength of the briquette to percolation leaching operation are discussed. Under optimum conditions, uranium leaching is 97.8% complete, a level comparable to agitation leaching. It is found that the mechanical strength of the calcined briquette meets the needs of percolation leaching operation. 98100138 The place of coking in coal processing Zielinski, H. K&o-Energochemical-Ekol., 1996, 41, (1) 3-7. (In Polish) Coal remains as the main energy source and methanol synthesis may be the chance for its mass processing. World coal use for coking industry will be 0.5 Gtons/yr. Coke production in Poland has decreased from 20 to 11 Mtons/yr and it is assumed it will increase to 13-14 Mtonsiyr after modernization. Another question for the coking industry is to start cokelike formed fuel production. 98/00139 Polymerization of anthracene-oil by thermal treatment in the presence of aluminum trichloride Fernandez, A. L. ef al. DGMK Tagungsber., 1997, 9703, (Proceedings ICCS ‘97, Volume 2), 901-904. Anhydrous AICIs in several concentrations was used in the polymerization of commercial anthracene oil in the range 250-325°C. The kinetics of the process and the degree of conversion of the anthracene oil were monitored by thermogravimetric analysis and the evolution of the concentration of the main anthracene oil components was monitored by GC. At 900°C the coke obtained from the pitches were characterized by their optical texture and their reactivity with air at 1000°C.
98100140 Preparation of pitches by coal-tar air-blowing Prada, V. et al. DGMK Tagungsber., 1997, 9703, (Proceedings ICCS ‘97, Volume 2), 893-896. At temperatures of 275 and 300°C three coal tar pitches were prepared by air-blowing of tar under gas pressure. The resulting pitches were characterized by their physical and chemical properties as well as their pyrolysis behaviour. Pitches obtained by thermogravimetric analysis at temperatures of 900 and 1000°C yielded cokes with an optical texture from flow domains to mosaics, depending on the temperature and duration of treatment. 98lOO141 The process of utilization of organic waste by method of hard coal coking Zmuda, W. et al. DGMK Tagungsber., 1997, 9703, (Proceedings ICCS ‘97, Volume 2), 853-856. Various organic wastes were mixed with coal tar pitch or petroleum asphalt and solid carbonaceous waste material. The resulting products were granulated and blended with coal for the coking process. The paper describes properties of granulates with different composition as well as the properties of the resulting cokes.
12
Fuel and Energy Abstracts
January 1998
98100142 Production of brown coal-based fireplace fuel Haege, K. et al. Ger. DE 19,614,715 (Cl. ClOLS/O2), 10 Jul 1997, Appl. 19,614,715, 13 Apr 1996, 3 pp. (In German) Mixing of 65-75 weight parts brown-coal fines with 25-35 weight parts molten paraffin wax at a temperature lower than the wax melting point produces this fuel. Alternatively, 65-75 weight parts brown-coal dust mixed with 25-35 weight parts molten paraffin wax at a temperature equal or higher than the wax melting point can be used. The resulting mixture is pressed at
98100143 Relations between degree of graphitization and galvanomagnetic properties of pyrolytic carbons and cokes Iwashita, N. et al. Carbon, 1997, 35, (8), 1073-1077. The paper studies the relationships between degree of graphitization (P,) and galvanomagnetic properties [maximum magnetoresistance (AA/A)maximum Hall coefficient RH and electrical resistivity Q] for pyrolytic carbons and cokes treated at different temperatures. With increasing heat treatment temperature, sign changes from negative to positive in (AQ/Q),,,., and from positive to negative in RH took place at Pi 0.5, irrespective of the specimen. Such a phenomenon implies that electronic conduction in these specimens changes from a one-carrier type to a two-carrier type when the threedimensional graphitic stacking order becomes predominant in the volume fraction. Galvanomagnetic parameters as a function of Pi depend considerably on the texture of the C materials. However, a positive value of (AQIQ)m.,x was observed as a unique function of the crystallite size of the hexagonal C layers, independent of the specimen. The degree of orientation of the hexagonal layers strongly affects the absolute value of RH. 98100144 Separation of sulfur from metallurgical coke by temperature treatment up to 2400” Legin-Kolar, M. and Radenovic, A. DGMK Tagungsber., 1997, 9703, (Proceedings ICCS ‘97, Volume 2) 757-760. Both before and after thermal treatment of various coke samples at 1200, 1600, 2000, and 2400°C the sulfur content was analysed. The samples were heated at the rates of 10 and 30”Cimin for 2 and 4 h. The cokes analysed were manufactured both with and without additives. In the case of the coke produced from the cooking coal and coal tar pitch as additive, it was found that the separation following high temperature treatment was the most efficacious. In the cokes that passed through the cooking process, only some of the S compounds present in the cooking coal were identified. After heating up to 1600°C all of the inorganic sulfur was separated from the cokes produced with the additives. The sulfur determined in the range 1600-2400°C was organic in origin.
98100145 Studies on generation of excessive coking pressure. 1. Semicoke contraction versus thermoplastic properties of coals Alvarez, R. er al. Energy Fuels, 1997, 11, (5). 978-981. Forty-two coals were studied regarding their thermoplastic properties and the volume contraction/expansion observed for their semi-coke layers. The objective was to attempt to find an interrelation between coal thermoplasticity and semi-coke contraction. The results, which may lend support to one or both accepted views of the mechanism of generation of excessive coking pressure by some coals, may also have application on laboratory testing methods for coking coals. The Gieseler thermoplastic properties and the contraction values of carbonized coals by the Koppers-INCAR tests were measured. In general, rather diffused or no relationships were found between the contraction on one hand and the thermoplastic properties on the other. The above two views may be synthesised on the condition that causative links could be found between more specific characteristics of thermal decomposition during coal plastic state and contraction of semicoke layer.
98100146 Studies on generation of excessive coking pressure. 2. Field ionization mass spectrometry of coals showing different contraction during carbonization Marzec, A. et al. Energy Fuels, 1997, 11, (5) 982-986. Various coals of different volume contraction/expansion and ‘wall’ pressures were heated and their decomposition products were analysed by pyrolysis field ionization mass spectrometry (Py-FIMS). The experiments aimed to characterize features of thermal decomposition of the coals that influence their contraction as well as their ‘wall’ pressure development during coking. A relationship was observed; Py-FIMS results indicated that the contraction values depend on (1) yields of thermal degradation products generated in coals upon their heating to the resolidification temperature and (2) individual composition of the thermal decomposition products. Coals showed high contraction values and low wall pressures when their yields of thermal degradation products were > 14 wt% and also when high-alkylated aromatics predominated over low-alkylated aromatics in the products. The yield and composition of thermal degradation products generated in the plastic layer influenced not only the contraction of the semi-coke layer but also the permeability for gaseous and vapour products.