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01795 Conversion method of coal
01
Solid fuels (preparation)
high ash coal; (3) production of clean coal samples and preparation of beneficiated coal-water mixtures (BCWM); (4) characterization of the BCWM and evaluation of their combustion properties; (5) process optimization for both the fines and the high ash coal and examination of two possible variants for their treatment.
99101795
Conversion method of coal
Arai, K. et al. Jpn. Kokai Tokkyo Koho JP 10 237,459 [98 237,459] (Cl. ClOG1/06), 8 Sep 1998, Appl. 97/43,351, 27 Feb 1997, 4 pp. (In Japanese) In coal conversion, one method comprises; (1) pretreating pulverized coal with water to form a 5-60 wt% coal slurry in a pre-treatment stage, (2) liquefying the coal slurry under supercritical conditions by simultaneously combining reactions of coal hydrolytic reactions, coal thermal decomposition reactions and reactions of unreacted coal and active hydrogen to give lighter products from coal in a coal liquefaction stage and (3) fractionating the oil-containing supercritical water from the liquefaction stage by pressure-reducing and cooling in stages.
Coprocessing Yanzhou coal with petroleum residue 99101796 Ling, K. and Zou, G. Meitan Zhuanhua, 1997, 20, (2), 62-66. (In Chinese) In a resonance stirring reactor, three bituminous coals and one petroleum residue were coprocessed at 430°C and 7.0 MPa (H). The results showed that the coal conversions increased with the increase of H/C atomic ratios and vitrinite in the coals. Three bituminous coals and their remainders were analysed by FTIR. The mechanism of coprocessing coal with residua was suggested. 99101797
Finely ground coals, ilmenite slimes and gold finely disseminated in a slag have been treated by this process. In this way, coal which is clean and with low ash and sulfur remaining and high Btu recovery can be obtained. Further, the refractory ores of ilmenite slimes and fine gold-bearing slag can be reasonably concentrated, leading to better beneficiation results than other separation techniques.
Development of mill fuel drying plants with cam-
wheel mills
Unland, G. et al. VGB Kraftwerksfech., 1998, 78, (6), 76-80. (In German) This paper describes a strategy for the development and optimization of cam-wheel mills which dry and crush brown coal for direct fuelling of power stations. The three-step strategy consisted of: (1) numerical simulation, in order to understand and describe the effects which appear in each part of the plant, (2) measurements on models of the plant, (3) changes in the construction of the plant itself. This development strategy has advantages in cost, time and implementation.
DszD utilization in desulfurization of diben-zothiophene by Rhodococcus specific IGTSI
99101802 Improvement of distribution of air-flux and coal at feeding points Rampelberg, D. Comm. Eur. Communifies, [Rep.] EUR, 1998, (EUR 17936) l-107. (In French) This study aimed to prove whether the location of sensors in a piping system for feeding of coal in a coal processing (e.g., coking) plant had an impact. It was found that although the location of the sensor has an influence on the type of information given, it appears that adjusting the location does not have to be dependent on the type of coal. The best location was found in a pipe bend. An example is given for an impact sensor in the coal feeding tube which would measure the particle flow and the aerodynamic profile of the particles.
99lO1803 Interpretation of the effect of froth structure on the performance of froth flotation using image analysis Banford, A. W. et al. Powder Technol., 1998, 98, (1) 61-73. An investigation took place into the possibility of regulating the performance of a coal flotation cell by using image analysis to define a desired bubble size in the concentrate. The measured deviations were used to control bubble coalescence by the compensating addition of surfactants. Image analysis was carried out on a transputer-enhanced Micro Vax computer off-line, using video images of experimental semi-batch runs. Individual runs were carried out using a single surfactant which had to act both as a frother and collector; two surfactants 2-ethylhexanol and Triton X-405 were used. Data from the image analysis was interpreted together with experimental measurements of particle and water recoveries in terms of a previously formulated froth kinetic model. Physical plausible parameters were produced by the correlation of the point rates of overflow of dry-mineral-matter-free coal in terms of the model.
99101798
Gray, K. et al. U.S. US 5,811,285, (Cl. 435-252.3; C12N1/20), 22 Sep 1998, Appl. 715,554, 19 Sep 1996, 20 pp. Oxidoreductase addition to the biocatalyst of the desulfurization of fossil fuels enhances the rate of reaction. The method for the desulfurization of a fossil fuel containing organic sulfur compounds involves: contacting the fossil fuel with an aqueous phase containing a biocatalyst capable of cleaving carbon-sulfur bonds and a rate-enhancing amount of an oxidoreductase, thereby forming a fossil fuel and aqueous phase mixture; maintaining this mixture under conditions sufficient for cleavage of the carbon-sulfur bonds of the organic sulfur molecules by the biocatalyst, thereby resulting in a fossil fuel having a reduced organic sulfur content; and then separating the fossil fuel having a reduced organic sulfur content from the resulting aqueous phase. The recombinant microorganism contains one or more recombinant DNA molecules which encode the biocatalyst and the oxidoreductase. This combination of biocatalyst and oxidoreductase is useful for the desulfurization of coal, crude oil and petroleum distillates.
99101799 chlorine
Ebullience
calcination
of coal-series
kaolin by
Ron, Z. and Xia, Y. Feijinshukuang, 1998, (4), 29-31. (In Chinese) A study of the ebullience calcination of coal-series kaolin by chlorine addition. The thermodynamic principle for iron and thallium removal through chlorine roasting is introduced. During the calcination process the particle size was 325-400 mesh, the temperature was 800-900°C the chlorine content was 3% of the kaolin weight and the raw iron and thallium was 0.6%-0.8%. 99lO1800
Effect of properties of circulating gas on coke
quenching
Przybylak, A. and Starzycki, J. Kurbo-Energochem.-Ekol., 1998, 43, (7), 223-225. (In Polish) In this paper, some practical comments are given on the effects of circulating gas composition on the process of coke quenching. Additionally, effects on the durability of devices is discussed.
Hydrophobic flocculation flotation for beneficiating 99lO1801 fine coal and minerals Song,S. and Valdivieso, A. L. Separate Sci. Technol., 1998, 33, (8), 1195-
1212. An effective process for treating finely ground ores and slimes in order to concentrate coal and mineral values at a fine size range is through hydrophobic flocculation flotation (HFF). The process is based on first dispersing the fine particles suspension, followed by the flocculation of fine mineral values or coal in the form of hydrophobic surfaces either induced by specifically adsorbed surfactants or from nature at the conditioning of the slurry with the shear field of sufficient magnitude. Intensification of the flocculation takes place by the addition of a small amount of non-polar oil.
155 Fuel and Energy Abstracts
May 1999
Investigations into obtaining constant feed rates 99101804 from screw feeders Wiche, S. J. and Roberts, A. W. World Congr. Part. Technol. 3, [computer optical disk], 1998, 3797-3807. Screw feeders provide good volumetric feed control over extended periods and are often used in bulk materials handling and powder processing industries. However the feed rate may vary. For dry non-cohesive materials it pulses significantly with each screw revolution and for cohesive materials it changes erratically during each screw revolution due to intermittent material hang-up at the discharge outlet. For feed to coal fired boilers and flash furnace smelters where feed fluctuations affect the flame stability, these fluctuations in flow rate can have a detrimental effect on process control and thus adversely affect the plant’s operation. An experimental screw feeder rig, capable of measuring the pulsation and erratic feed phenomenon, was constructed to investigate methods to overcome these problems. Tests were undertaken by using bulk materials with a range of material properties to arrive at a simple but effective solution to the feed fluctuation problem. It is demonstrated that the solution found will smooth the discharge flow rate for a variety of bulk materials and bulk material properties from free flowing to cohesive. An actual pulverized fuel coal screw feeder exhibiting pulsing feed is examined for implementation of the smoothing system.
99lO1805 iron-catalyzed coprocessing of coals and vacuum residues using syngas-water as a hydrogen source Hata, K.-a. et al. Energy Fuels, 1998, 12, (6), 1181-1190. This study investigates the effectiveness of alternative hydrogen sources compared to pressurized hydrogen gas toward the coprocessing of coals and vacuum residues. The process was undertaken in the presence of different kinds of iron-based catalyst precursors. The reactions in syngas-water using pentacarbonyliron or synthetic pyrite achieved high rates of conversion to tetrahydrofuran solubles comparable to those in pressurized hydrogen gas. Thus, indicating the presence of the synergistic effects of the two hydrogen sources, hydrogen gas and carbon monoxide-water. Under hydrogen gas, addition of water greatly increased the yields of the desired fractions. The Fe(CO)s-catalysed coprocessing of a vacuum residue of Arabian Heavy and Wandoan coal in combination with the pre-treatment at lower temperature (200°C for 30 minutes) afforded high yields of tetrahydrofuran-soluble (100%) and n-hexane-soluble (69.5%) matter. At higher reaction temperatures, 425-45o”C, the addition of sulfur or synthetic pyrite to Fe(C0)s improved rates of conversion. X-ray diffraction and X-ray photoelectron spectroscopy analyses revealed the formation of a mixture of magnetite and pyrrhotite from Fe(CO)s without sulfur. Further, the surface of the used catalyst was revealed to be mainly covered with iron species in a relatively high oxidation state. Pyrrhotite was formed from Fe(CO)s with sulfur or synthetic pyrite. The gas consumption, eventually the efficiency of the coprocessing, is suggested to be influenced by such changes in the state of the catalyst surface.
Solid fuels (preparation)
high ash coal; (3) production of clean coal samples and preparation of beneficiated coal-water mixtures (BCWM); (4) characterization of the BCWM and evaluation of their combustion properties; (5) process optimization for both the fines and the high ash coal and examination of two possible variants for their treatment.
99101795
Conversion method of coal
Arai, K. et al. Jpn. Kokai Tokkyo Koho JP 10 237,459 [98 237,459] (Cl. ClOG1/06), 8 Sep 1998, Appl. 97/43,351, 27 Feb 1997, 4 pp. (In Japanese) In coal conversion, one method comprises; (1) pretreating pulverized coal with water to form a 5-60 wt% coal slurry in a pre-treatment stage, (2) liquefying the coal slurry under supercritical conditions by simultaneously combining reactions of coal hydrolytic reactions, coal thermal decomposition reactions and reactions of unreacted coal and active hydrogen to give lighter products from coal in a coal liquefaction stage and (3) fractionating the oil-containing supercritical water from the liquefaction stage by pressure-reducing and cooling in stages.
Coprocessing Yanzhou coal with petroleum residue 99101796 Ling, K. and Zou, G. Meitan Zhuanhua, 1997, 20, (2), 62-66. (In Chinese) In a resonance stirring reactor, three bituminous coals and one petroleum residue were coprocessed at 430°C and 7.0 MPa (H). The results showed that the coal conversions increased with the increase of H/C atomic ratios and vitrinite in the coals. Three bituminous coals and their remainders were analysed by FTIR. The mechanism of coprocessing coal with residua was suggested. 99101797
Finely ground coals, ilmenite slimes and gold finely disseminated in a slag have been treated by this process. In this way, coal which is clean and with low ash and sulfur remaining and high Btu recovery can be obtained. Further, the refractory ores of ilmenite slimes and fine gold-bearing slag can be reasonably concentrated, leading to better beneficiation results than other separation techniques.
Development of mill fuel drying plants with cam-
wheel mills
Unland, G. et al. VGB Kraftwerksfech., 1998, 78, (6), 76-80. (In German) This paper describes a strategy for the development and optimization of cam-wheel mills which dry and crush brown coal for direct fuelling of power stations. The three-step strategy consisted of: (1) numerical simulation, in order to understand and describe the effects which appear in each part of the plant, (2) measurements on models of the plant, (3) changes in the construction of the plant itself. This development strategy has advantages in cost, time and implementation.
DszD utilization in desulfurization of diben-zothiophene by Rhodococcus specific IGTSI
99101802 Improvement of distribution of air-flux and coal at feeding points Rampelberg, D. Comm. Eur. Communifies, [Rep.] EUR, 1998, (EUR 17936) l-107. (In French) This study aimed to prove whether the location of sensors in a piping system for feeding of coal in a coal processing (e.g., coking) plant had an impact. It was found that although the location of the sensor has an influence on the type of information given, it appears that adjusting the location does not have to be dependent on the type of coal. The best location was found in a pipe bend. An example is given for an impact sensor in the coal feeding tube which would measure the particle flow and the aerodynamic profile of the particles.
99lO1803 Interpretation of the effect of froth structure on the performance of froth flotation using image analysis Banford, A. W. et al. Powder Technol., 1998, 98, (1) 61-73. An investigation took place into the possibility of regulating the performance of a coal flotation cell by using image analysis to define a desired bubble size in the concentrate. The measured deviations were used to control bubble coalescence by the compensating addition of surfactants. Image analysis was carried out on a transputer-enhanced Micro Vax computer off-line, using video images of experimental semi-batch runs. Individual runs were carried out using a single surfactant which had to act both as a frother and collector; two surfactants 2-ethylhexanol and Triton X-405 were used. Data from the image analysis was interpreted together with experimental measurements of particle and water recoveries in terms of a previously formulated froth kinetic model. Physical plausible parameters were produced by the correlation of the point rates of overflow of dry-mineral-matter-free coal in terms of the model.
99101798
Gray, K. et al. U.S. US 5,811,285, (Cl. 435-252.3; C12N1/20), 22 Sep 1998, Appl. 715,554, 19 Sep 1996, 20 pp. Oxidoreductase addition to the biocatalyst of the desulfurization of fossil fuels enhances the rate of reaction. The method for the desulfurization of a fossil fuel containing organic sulfur compounds involves: contacting the fossil fuel with an aqueous phase containing a biocatalyst capable of cleaving carbon-sulfur bonds and a rate-enhancing amount of an oxidoreductase, thereby forming a fossil fuel and aqueous phase mixture; maintaining this mixture under conditions sufficient for cleavage of the carbon-sulfur bonds of the organic sulfur molecules by the biocatalyst, thereby resulting in a fossil fuel having a reduced organic sulfur content; and then separating the fossil fuel having a reduced organic sulfur content from the resulting aqueous phase. The recombinant microorganism contains one or more recombinant DNA molecules which encode the biocatalyst and the oxidoreductase. This combination of biocatalyst and oxidoreductase is useful for the desulfurization of coal, crude oil and petroleum distillates.
99101799 chlorine
Ebullience
calcination
of coal-series
kaolin by
Ron, Z. and Xia, Y. Feijinshukuang, 1998, (4), 29-31. (In Chinese) A study of the ebullience calcination of coal-series kaolin by chlorine addition. The thermodynamic principle for iron and thallium removal through chlorine roasting is introduced. During the calcination process the particle size was 325-400 mesh, the temperature was 800-900°C the chlorine content was 3% of the kaolin weight and the raw iron and thallium was 0.6%-0.8%. 99lO1800
Effect of properties of circulating gas on coke
quenching
Przybylak, A. and Starzycki, J. Kurbo-Energochem.-Ekol., 1998, 43, (7), 223-225. (In Polish) In this paper, some practical comments are given on the effects of circulating gas composition on the process of coke quenching. Additionally, effects on the durability of devices is discussed.
Hydrophobic flocculation flotation for beneficiating 99lO1801 fine coal and minerals Song,S. and Valdivieso, A. L. Separate Sci. Technol., 1998, 33, (8), 1195-
1212. An effective process for treating finely ground ores and slimes in order to concentrate coal and mineral values at a fine size range is through hydrophobic flocculation flotation (HFF). The process is based on first dispersing the fine particles suspension, followed by the flocculation of fine mineral values or coal in the form of hydrophobic surfaces either induced by specifically adsorbed surfactants or from nature at the conditioning of the slurry with the shear field of sufficient magnitude. Intensification of the flocculation takes place by the addition of a small amount of non-polar oil.
155 Fuel and Energy Abstracts
May 1999
Investigations into obtaining constant feed rates 99101804 from screw feeders Wiche, S. J. and Roberts, A. W. World Congr. Part. Technol. 3, [computer optical disk], 1998, 3797-3807. Screw feeders provide good volumetric feed control over extended periods and are often used in bulk materials handling and powder processing industries. However the feed rate may vary. For dry non-cohesive materials it pulses significantly with each screw revolution and for cohesive materials it changes erratically during each screw revolution due to intermittent material hang-up at the discharge outlet. For feed to coal fired boilers and flash furnace smelters where feed fluctuations affect the flame stability, these fluctuations in flow rate can have a detrimental effect on process control and thus adversely affect the plant’s operation. An experimental screw feeder rig, capable of measuring the pulsation and erratic feed phenomenon, was constructed to investigate methods to overcome these problems. Tests were undertaken by using bulk materials with a range of material properties to arrive at a simple but effective solution to the feed fluctuation problem. It is demonstrated that the solution found will smooth the discharge flow rate for a variety of bulk materials and bulk material properties from free flowing to cohesive. An actual pulverized fuel coal screw feeder exhibiting pulsing feed is examined for implementation of the smoothing system.
99lO1805 iron-catalyzed coprocessing of coals and vacuum residues using syngas-water as a hydrogen source Hata, K.-a. et al. Energy Fuels, 1998, 12, (6), 1181-1190. This study investigates the effectiveness of alternative hydrogen sources compared to pressurized hydrogen gas toward the coprocessing of coals and vacuum residues. The process was undertaken in the presence of different kinds of iron-based catalyst precursors. The reactions in syngas-water using pentacarbonyliron or synthetic pyrite achieved high rates of conversion to tetrahydrofuran solubles comparable to those in pressurized hydrogen gas. Thus, indicating the presence of the synergistic effects of the two hydrogen sources, hydrogen gas and carbon monoxide-water. Under hydrogen gas, addition of water greatly increased the yields of the desired fractions. The Fe(CO)s-catalysed coprocessing of a vacuum residue of Arabian Heavy and Wandoan coal in combination with the pre-treatment at lower temperature (200°C for 30 minutes) afforded high yields of tetrahydrofuran-soluble (100%) and n-hexane-soluble (69.5%) matter. At higher reaction temperatures, 425-45o”C, the addition of sulfur or synthetic pyrite to Fe(C0)s improved rates of conversion. X-ray diffraction and X-ray photoelectron spectroscopy analyses revealed the formation of a mixture of magnetite and pyrrhotite from Fe(CO)s without sulfur. Further, the surface of the used catalyst was revealed to be mainly covered with iron species in a relatively high oxidation state. Pyrrhotite was formed from Fe(CO)s with sulfur or synthetic pyrite. The gas consumption, eventually the efficiency of the coprocessing, is suggested to be influenced by such changes in the state of the catalyst surface.