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01837 Biodesulfurization of Turkish lignites. 2. Microbial desulfurization of Mengen lignite by the mesophilic microorganism Rhodococcus rhodochrous
01 partings have low concentrations of barium, hafnium, scandium, strontium, tantalum, thorium, uranium, and REEs; this along with the absence of an Eu negative anomaly suggests a non-volcanic origin for the partings.
Understanding of the mechanism of coal transltion into a plastic state. Part 2
98/01830
Ulanovskii, M. L. Koks Khim., 1997, (II), 2-4. (In Russian) The dynamics and mechanism of coal plasticization during considered.
coking
arc
The use of phenolic resins containing polynuclear 96lOl631 aromatic moieties to model aspects of coal pyrolysis
McRae, C. et al. Prepr. Pap. Am. Chemical Sot., Div. Fuel Chem., 1997, 42, (l), 107-111. Having diphenylmethane, benzylnaphthalene, benzylanthracene, benzylphenanthrene, and 2-naphthol as the second component, a suite of PAHcontaining resites were prepared. To illustrate the potential of the resites to study the formation of PAH in the utilization of solid fuels, the carbonization of the 9-(4-hydroxybenzyl)anthracene-containing resite has been investigated in a fluidized-bed reactor.
Variable-temperature EPR studies of lllinols No. 6 coal treated with donor and acceptor molecules
9BlOl832
Thompson, R. L. et al. Energy Fuels, 1997, 11, (3) 739-746. The paper reports variable-temperature EPR studies of Illinois No. 6 coal, its pyridine extract and samples of each after treatment with known donor and acceptor molecules. The purpose of the study was to explore the origin of the EPR signals near g = 2 and to elucidate the nature of non-covalently bonded interactions in coal. Curie Law behaviour is exhibited for each sample, indicating that the EPH signals are dominated by doublet state species. No evidence for thermally accessible, low-lying triplet states, such as those found in some charge-transfer complexes, was found. IR spectroscopy suggests, however, that electron transfer from the coal does occur after treatment with electron acceptors such as TCNQ and TCNE. EPR studies of the Illinois No. 6 coal samples after treatment with the known electron donor ‘ITF showed that TTF radical cation had been formed.
96lOt 633
Weathering of solid fuels
Postrzednik, S. Gospod. Paliwami Energ., 1996, 44, (12), 7-11. (In Polish) For the purpose of evaluating the weathering of solid fuels, a simple calculation method was derived. Fuel composition data were used and the rate of the weathering process, mass losses and energy losses were determined. The method’s suitability was verified experimentally.
X-ray scattering analysis of the average polycyclic 98/01634 aromatic unit in Argonne Premium Coal 401 Wertz, D. L. Fuel, 1998 (Pub. 1997), 77, (l/2), 43-53. Using MoK,. X-rays, an X-ray scattering study of APC 401 indicates that the longest distance between carbon atoms in the mean polycyclic aromatic (PCA) unit is approximately 7.5 A. The radial-distribution function indicates that, on average, each carbon 2.2 nearest carbon neighbours at an average distance of 1.43 A. This information is consistent with the interpretation that 27% of the C-C bonds in this coal involve at least one alkyl carbon, while 73% of the C-C bonds are between aryl carbons. Comparisons of the atom-pair correlation function to simulated onedimensional structure functions calculated from three-dimensional structural models of several polycyclic molecules indicate that a ribbon-shaped Cl4 unit best agrees with the results of our X-ray scattering data. Interpretation of the atom-pair correlation function also suggests that the alkyl carbons are predominantly, if not exclusively, bonded to the PCA unit.
Zeta potential of a subbituminous 98/01635 effect on particle agglomeration
coal and its
Lin, Y. and Liu, H. Trans. Sot. Min., Metall., Explor., 1996 (Pub. 1997), 300,31-35. A study was conducted to observe the zeta potential characteristics of a Powder River Basin coal in water and the effects of zeta potential on the agglomeration of coal particles. The electrokinetic measurements show that the zeta potential of the coal is dependent on pH, temperature, coal concentration and contact time with water. The effects of various additives for changing the zeta potential of the coal were also evaluated. It was found that the strength of the coal agglomerates is increased when the zeta potential diminishes. Neutralizing the zeta potential enhances agglomeration. Therefore, it is important to control the zeta potential of coal to achieve optimum performance in coal particle agglomeration.
Solid fuels (preparation)
pressure. The sonication of coal samples led to a maximum reduction of 59 wt% in total sulfur in a low rank coal, while 13 to 22 wt% of total sulfur was removed from other sub-bituminous coals by employing a 1 M NaOH solution at 30°C. Leaching under these conditions, a reduction of 53 wt% in ash was achieved in a low ash content (6.8 wt%) coal compared with 5-25 wt% for high ash content coals. The study also investigated the effects of alkali concentration, coal particle size, temperature and time on the demineralization efficiency of coals.
Biodesulfurization of Turkish Iignites. 2. Microbial desulfurization of Mengen lignite by the mesophilic microorganism Rhodococcus rhodochrous
90iOl637
Durusoy, T. et al. Fuel 1997, 76, (4), 341-344. The paper examines the effects of substrate type in the growth medium, the mixing time of lignite into the growth medium and the biodesulfurization time on sulfur removal. Biodesulfurization experiments were carried out with Mengen lignite under optimum growth conditions with Rhodococcus rhodochrous. When sodium acetate was the substrate, the highest reduction of organic sulfur was 27.1%. Sulfate sulfur could be totally reduced when lignite was added to the culture medium 24 h after incubation. Compared with sodium acetate, glycerol yielded higher sulfate sulfur reduction rates when lignite was added at the time of incubation. The highest organic sulfur removal rates were observed when sodium acetate was the substrate.
96lO1636
Biomass in clean coal production
Knudson, C. L. and Pedersen, M. P. Proc. Biomass Conf. Am.: Energy, Environ., Agric. Ind., 2nd, 1995, 1255-1261. During coal cleaning processes, the coal is crushed and then cleaned, resulting in a fine clean coal product, which makes it more difficult to ship and handle. Combining biomass with cleaned coal is one method to produce a dust-free, lump, biomass-coal product that is readily shippable. Work has recently been completed by the University of North Dakota Energy and Environmental Research Center (UNDEERC), funded by the North Dakota Industrial Commission and Knife River Coal Mining Company, which demonstrates that cleaned coal could be successfully briquetted using biomass. Joint work between Grand Forks Activation Technologies (GFAT) and the Knife River Coal Mining Company has concentrated on the further development and commercialization of the coal cleaning process. GFAT is also working with Producers Renewable Products, LLC to further develop and commercialize the use of other agricultural waste products, such as stillage concentrate, in the production of biomass-coal fuel products. This process addresses two problems: how to clean water inexpensively for recycling in an ethanol plant and how to get an inexpensive binder for reconstitution of coal by pelletization. Phase I evaluates the feasibility of each processing step as well as the end product and the overall economic benefits. If successful, it will improve the reconstitution, dewatering, and handling of coal making it a more marketable product. A number of economic and environmental benefits are offered by this process. The use of cleaned coal as a plant fuel would free up valuable propane or natural gas for use in homes, prevent plant interruptions due to winter demand shutdowns, decrease plant fuel costs, and increase the number of jobs in the local community since coal is a more labour-intensive fuel than natural gas, propane, or oil. The integration of coal into water treatment in an ethanol plant could increase ethanol yields by 9% while providing a by-product of clean, pelletized fuel. Using city water treatment sludge in the process would enable a second use and possibly a third since the calcium-enhanced ash could be a better soil stabilizer or could be used to treat alkali farm land. 96iO1639
Coal desulfurlzatlon by mild pyrolysis in a dualauger coal feeder
Lin, L. et al. Fuel Process. Technol., 1997, 53, (1,2), 15-29. The paper describes a dual-screw coal feeder reactor constructed and tested for coal desulfurization. The reactor consists of two concentric screw tubes, the inner tube acting as a coal pyrolyser and the outer tube acting as a desulfurizer with hot calcined lime (CaO) pellets or other renewable sorbent pellets. Under mild pyrolysis conditions, the devolatilization and the desulfurization processes of Ohio #8 coal could be represented by a pseudo first-order reaction model. At 475°C and a residence time of 6 min, up to 33.2% of the total sulfur was removed using a coal particle size of 435 mesh. The activation energies for the devolatilization and the desulfurization processes were estimated to be 170,021 kJ/kg mol. and 78,732 kJ/kg mol., respectively. In the pyrolysed gas, the HzS concentration was reduced to an undetectable level in the outer tube desulfurizer, indicating a high sulfur removal efficiency of CaO pellets in the dual-screw feeder reactor.
Preparation 9BiOl640 Collectorless flotation of coal with two-stage addition of pine oil 9BlOl636
coals
Application of sonic energy to caustic cleanlng of
Zaidi, S. A. H. Fuel Process. Technol. 1997, 53, (1,2), 31-39. An investigation was carried out into the combined effect of sonic energy and sodium hydroxide on the desulfurization of different high sulfur and high ash content coals at from ambient to 60°C and at atmospheric
Dey, S. et al. Miner. Metall. Process., 1997, 14, (4), 13-16. Experiments testing coal batch flotation were performed both with and without collector and with one- and two-stage frother additions (i.e. pine oil and diesel fuel). Both with and without collector, the recovery of combustibles and the flotation rate constant were higher with two-stage frother addition.
Fuel and Energy Abstracts
May 1996
169
Understanding of the mechanism of coal transltion into a plastic state. Part 2
98/01830
Ulanovskii, M. L. Koks Khim., 1997, (II), 2-4. (In Russian) The dynamics and mechanism of coal plasticization during considered.
coking
arc
The use of phenolic resins containing polynuclear 96lOl631 aromatic moieties to model aspects of coal pyrolysis
McRae, C. et al. Prepr. Pap. Am. Chemical Sot., Div. Fuel Chem., 1997, 42, (l), 107-111. Having diphenylmethane, benzylnaphthalene, benzylanthracene, benzylphenanthrene, and 2-naphthol as the second component, a suite of PAHcontaining resites were prepared. To illustrate the potential of the resites to study the formation of PAH in the utilization of solid fuels, the carbonization of the 9-(4-hydroxybenzyl)anthracene-containing resite has been investigated in a fluidized-bed reactor.
Variable-temperature EPR studies of lllinols No. 6 coal treated with donor and acceptor molecules
9BlOl832
Thompson, R. L. et al. Energy Fuels, 1997, 11, (3) 739-746. The paper reports variable-temperature EPR studies of Illinois No. 6 coal, its pyridine extract and samples of each after treatment with known donor and acceptor molecules. The purpose of the study was to explore the origin of the EPR signals near g = 2 and to elucidate the nature of non-covalently bonded interactions in coal. Curie Law behaviour is exhibited for each sample, indicating that the EPH signals are dominated by doublet state species. No evidence for thermally accessible, low-lying triplet states, such as those found in some charge-transfer complexes, was found. IR spectroscopy suggests, however, that electron transfer from the coal does occur after treatment with electron acceptors such as TCNQ and TCNE. EPR studies of the Illinois No. 6 coal samples after treatment with the known electron donor ‘ITF showed that TTF radical cation had been formed.
96lOt 633
Weathering of solid fuels
Postrzednik, S. Gospod. Paliwami Energ., 1996, 44, (12), 7-11. (In Polish) For the purpose of evaluating the weathering of solid fuels, a simple calculation method was derived. Fuel composition data were used and the rate of the weathering process, mass losses and energy losses were determined. The method’s suitability was verified experimentally.
X-ray scattering analysis of the average polycyclic 98/01634 aromatic unit in Argonne Premium Coal 401 Wertz, D. L. Fuel, 1998 (Pub. 1997), 77, (l/2), 43-53. Using MoK,. X-rays, an X-ray scattering study of APC 401 indicates that the longest distance between carbon atoms in the mean polycyclic aromatic (PCA) unit is approximately 7.5 A. The radial-distribution function indicates that, on average, each carbon 2.2 nearest carbon neighbours at an average distance of 1.43 A. This information is consistent with the interpretation that 27% of the C-C bonds in this coal involve at least one alkyl carbon, while 73% of the C-C bonds are between aryl carbons. Comparisons of the atom-pair correlation function to simulated onedimensional structure functions calculated from three-dimensional structural models of several polycyclic molecules indicate that a ribbon-shaped Cl4 unit best agrees with the results of our X-ray scattering data. Interpretation of the atom-pair correlation function also suggests that the alkyl carbons are predominantly, if not exclusively, bonded to the PCA unit.
Zeta potential of a subbituminous 98/01635 effect on particle agglomeration
coal and its
Lin, Y. and Liu, H. Trans. Sot. Min., Metall., Explor., 1996 (Pub. 1997), 300,31-35. A study was conducted to observe the zeta potential characteristics of a Powder River Basin coal in water and the effects of zeta potential on the agglomeration of coal particles. The electrokinetic measurements show that the zeta potential of the coal is dependent on pH, temperature, coal concentration and contact time with water. The effects of various additives for changing the zeta potential of the coal were also evaluated. It was found that the strength of the coal agglomerates is increased when the zeta potential diminishes. Neutralizing the zeta potential enhances agglomeration. Therefore, it is important to control the zeta potential of coal to achieve optimum performance in coal particle agglomeration.
Solid fuels (preparation)
pressure. The sonication of coal samples led to a maximum reduction of 59 wt% in total sulfur in a low rank coal, while 13 to 22 wt% of total sulfur was removed from other sub-bituminous coals by employing a 1 M NaOH solution at 30°C. Leaching under these conditions, a reduction of 53 wt% in ash was achieved in a low ash content (6.8 wt%) coal compared with 5-25 wt% for high ash content coals. The study also investigated the effects of alkali concentration, coal particle size, temperature and time on the demineralization efficiency of coals.
Biodesulfurization of Turkish Iignites. 2. Microbial desulfurization of Mengen lignite by the mesophilic microorganism Rhodococcus rhodochrous
90iOl637
Durusoy, T. et al. Fuel 1997, 76, (4), 341-344. The paper examines the effects of substrate type in the growth medium, the mixing time of lignite into the growth medium and the biodesulfurization time on sulfur removal. Biodesulfurization experiments were carried out with Mengen lignite under optimum growth conditions with Rhodococcus rhodochrous. When sodium acetate was the substrate, the highest reduction of organic sulfur was 27.1%. Sulfate sulfur could be totally reduced when lignite was added to the culture medium 24 h after incubation. Compared with sodium acetate, glycerol yielded higher sulfate sulfur reduction rates when lignite was added at the time of incubation. The highest organic sulfur removal rates were observed when sodium acetate was the substrate.
96lO1636
Biomass in clean coal production
Knudson, C. L. and Pedersen, M. P. Proc. Biomass Conf. Am.: Energy, Environ., Agric. Ind., 2nd, 1995, 1255-1261. During coal cleaning processes, the coal is crushed and then cleaned, resulting in a fine clean coal product, which makes it more difficult to ship and handle. Combining biomass with cleaned coal is one method to produce a dust-free, lump, biomass-coal product that is readily shippable. Work has recently been completed by the University of North Dakota Energy and Environmental Research Center (UNDEERC), funded by the North Dakota Industrial Commission and Knife River Coal Mining Company, which demonstrates that cleaned coal could be successfully briquetted using biomass. Joint work between Grand Forks Activation Technologies (GFAT) and the Knife River Coal Mining Company has concentrated on the further development and commercialization of the coal cleaning process. GFAT is also working with Producers Renewable Products, LLC to further develop and commercialize the use of other agricultural waste products, such as stillage concentrate, in the production of biomass-coal fuel products. This process addresses two problems: how to clean water inexpensively for recycling in an ethanol plant and how to get an inexpensive binder for reconstitution of coal by pelletization. Phase I evaluates the feasibility of each processing step as well as the end product and the overall economic benefits. If successful, it will improve the reconstitution, dewatering, and handling of coal making it a more marketable product. A number of economic and environmental benefits are offered by this process. The use of cleaned coal as a plant fuel would free up valuable propane or natural gas for use in homes, prevent plant interruptions due to winter demand shutdowns, decrease plant fuel costs, and increase the number of jobs in the local community since coal is a more labour-intensive fuel than natural gas, propane, or oil. The integration of coal into water treatment in an ethanol plant could increase ethanol yields by 9% while providing a by-product of clean, pelletized fuel. Using city water treatment sludge in the process would enable a second use and possibly a third since the calcium-enhanced ash could be a better soil stabilizer or could be used to treat alkali farm land. 96iO1639
Coal desulfurlzatlon by mild pyrolysis in a dualauger coal feeder
Lin, L. et al. Fuel Process. Technol., 1997, 53, (1,2), 15-29. The paper describes a dual-screw coal feeder reactor constructed and tested for coal desulfurization. The reactor consists of two concentric screw tubes, the inner tube acting as a coal pyrolyser and the outer tube acting as a desulfurizer with hot calcined lime (CaO) pellets or other renewable sorbent pellets. Under mild pyrolysis conditions, the devolatilization and the desulfurization processes of Ohio #8 coal could be represented by a pseudo first-order reaction model. At 475°C and a residence time of 6 min, up to 33.2% of the total sulfur was removed using a coal particle size of 435 mesh. The activation energies for the devolatilization and the desulfurization processes were estimated to be 170,021 kJ/kg mol. and 78,732 kJ/kg mol., respectively. In the pyrolysed gas, the HzS concentration was reduced to an undetectable level in the outer tube desulfurizer, indicating a high sulfur removal efficiency of CaO pellets in the dual-screw feeder reactor.
Preparation 9BiOl640 Collectorless flotation of coal with two-stage addition of pine oil 9BlOl636
coals
Application of sonic energy to caustic cleanlng of
Zaidi, S. A. H. Fuel Process. Technol. 1997, 53, (1,2), 31-39. An investigation was carried out into the combined effect of sonic energy and sodium hydroxide on the desulfurization of different high sulfur and high ash content coals at from ambient to 60°C and at atmospheric
Dey, S. et al. Miner. Metall. Process., 1997, 14, (4), 13-16. Experiments testing coal batch flotation were performed both with and without collector and with one- and two-stage frother additions (i.e. pine oil and diesel fuel). Both with and without collector, the recovery of combustibles and the flotation rate constant were higher with two-stage frother addition.
Fuel and Energy Abstracts
May 1996
169