- Email: [email protected]
04396 Coal properties of upgraded low-rank coals by hot water drying method
01
So/id
97104369
fuels
(preparation)
Bed blending
of coals
Ruth, M. et al. peel. 1997. 76, (13). 1297-1300. Bed blending aims to improve the quality and consistency of the blended material. However, variations sometimes occur in beds, and so monitoring is necessary. Automatic petrographic techniques have been developed to determine the distribution of low-grade filler material within coal layers and the major components in blend samples. The major cause of variations in the properties of coke produced from coal blends was identified as uneven distribution of filler. Consequently, changes were made to bed construction which improved the consistency of the chemical and rheological properties of the blend and the physical properties of the coke.
97104390 fuels
Beneficiation
of coal fines toward
Beneficiation
of low grade anthracites
Lee, J.-J. et al. Chawon Risaikritzg.. 1996, 5, (2). 45-51. (In Korean) Sulfur levels of approximately 0.3-7s are found in South Korean coals. When burned, the sulfur may cause air pollution problems, as well as acid rain. The government decided to strengthen the environmental protection policy for the coal-fired plants, applied from I January 1999. This study was carried out to remove the S and mineral matters in the samples using wet magnetic separator and oil agglomeration apparatus. The results showed that the total sulfur removal from Kangung coal sample was 60.8% and 82.6% combustible recovery. For the results of oil agglomeration tests, comhustihle recovery, ash and sulfur removal from Mare coal sample were 98.0. 70.Y and 95.7%, respectively.
Biodesulfurization of Turkish Iignites. 2. Microbial 97104392 desulfurization of Mengen lignite by the mesophilic microorganism Rhodococcus rhodochrous Durusoy, T. EI al. Fuel, 1997, 76, (4). 341-344. Presents a study into the effects of substrate type in the growth medium. 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 of Rhodococcus rhodochrorrs. The highest reduction of organic sulfur forms was 27.1% using sodium acetate as the substrate. Sulfate sulfur could he completely 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 found when the substrate was sodium acetate.
Brown coal research in Slovakia from the point of 97104393 view of application of advanced cleaning technologies Turcaniova, L. et al. Proc. Annu. Inf. Pirrshurgh Coal Conf., 1996, 13, (2), 91 l-915. The scientific programme of the joint Slovak-American project of brown coal research in Slovakia is presented from the point of view of application of advanced cleaning technologies. The objective is to examine advanced clean coal technology under Slovakian conditions. At present the perspectives of brown coal mining are being assessed. The material and technological characteristics of the coal processing will be assessed together with evaluation of the perspective areas of use. Depending on the coal types, physical, chemical and biological processing technologies will he evaluated. The paper discusses the chemical characterization of different forms of as well as the Moesshauer spectroscopy of coal samples.
97104394 Changes in moisture parameters coals on low-temperature heat treatment
of higher
rank
Dunlop, N. F. and Johns, R. B. DGMK 7ag~ngshe~., 1997, 9702, (Proceedings ICCS. ‘97, Volume 1). 377-380. Marked changes in moisture equilibrium values at short treatment limes were induced by a series of low temperature heat treatments of three different coals in a flow of moist air. Changes in the chemical functional groups, within and on the surface of the coal were followed by DRIFT and MAS “C SSNMR spectroscopy. The formation of C-O single bonds is a major pathway of oxidation in early reactions. These lead to the C=O functionalities conventionally observed The progressive chemical changes observed may explain in part the observed variations in the moisture uptake and equilibrium moisture content of all three coals reported.
382
Fuel and Energy Abstracts
November
1997
kinetics
of a gas-promoted
oil
Zlhang, F. and W’heelock, T. D. Proc,. Anne. Int. Pirtsh~~$ Coral Conf:. 1996, 13, (I), s47-552. Gas-promoted oil agglomeration process kinetics were investigated by monitoring the change in the turbidity of an aqueous particle suspension as the particles were agglomerated with heptane in a closed tank fitted with baffles and an agitator. Measured amounts of air and heptane were added to a suspensions of Pittsburgh No. 8 coal under vigorous agitation. The subsequent rate of change of particle concentration was taken to he an indication of the rate of agglomeration. The rate was proportional to the particle number of concentration raised to a power and dependent on agitator speed and the amounts of air and oil added.
clean ecological
Sciazko, M. el a/. DGMK Tugu+$~r., 1997, Y702, (Proceedings ICCS ‘97, Volume I), 539-542. Ecological and smokeless fuels are prepared by granulation and hriquetting. The effective way to reduce noxious emissions from residential heating sector is elimination of coal from direct use; substituting it by ecolological solid fuels based on hard coal. Several such technologies were developed in the Institute for Chemical Processing of Coal (IChPW). The technologies hased on coal fines as a raw material permit the preparation of lowemission coal briquettes and granules of considerably higher ecological quality. even than high grade coal. The market for hriquetted solid fuels in Poland is estimated to he between I and 2 million t/year.
97104391
97104395 Coal beneficiation aaalomeration orocess
97104396 Coal properties water drying method
of upgraded
low-rank
coals by hot
Ohki. A. et al. DGMK Ta~~ng.she~., lYY7. 0702. (Proceedings ICCS ‘Y7. Volume I), 4X7-490. Hydrothermal treatment of various coals of different rank, at lSO~3Sll C in an autoclave, was carried out. With rising heat-treatment temperature (HTT). The hygroscopicity of low-rank coals gradually decreased. The content of carhoxyl group greatly decreased hy the treatment. hut a Its\ remarkable change in the content of hydroxyl group as well as that in the specific surface area of coal was noted.
97104397 Conditions for processing and dewatering slurries at Nagolchenskaya Central beneficiation plant
of coal
Muatafin, L. D. and Pul’chev. A. D. U$’ Ukr., lYY7, (2-3). 3X-411. (In Russian) In order to increase the efficiency of coal suspension capture at Nagolchenskaya Central beneficiation plant, a rearranged set ot hydrocyclones and conveyor vacuum filters were implemented. These mcasurcc decreased the solid content of recycled water to 100-120 kg/m’ and decreased the amount of solids discharged to settlers by 40%.
97104398
Desulfuriration
of coal using borax
Yaman, S. and Kucukbayrak, S. Proc. Amw. Int. P~rrshftr;qh Ccw/ (‘OH/:, 1996, 13, (l), 216-220. Varying amounts of solid borax was mixed with high sulfur Turkish lignite. These mixtures were then subjected to various oxydesulfurization processes. Effects of amount of borax, temperature and partial pressure of oxygen on sulfur removal and coal recovery were investigated in the ranges of O.h25IS.000 g for 5 g lignite, 423-498 K and O.O-I..5 MPa. respectively.
97104399 Desulfurization gravity separator
of low-rank
Turkish
coals by multi-
Aydin, M. E. et al. Proc. Anm. Int. Pitfshurgh Cm/ LhnJ:. IYYh. 1.3. ( I ), 437-442. High moisture contents (average 3.5%). high volatile matter value\ (average 45%). and, more importantly. high levels of sulfur in the range of I-5’;, are features of Istanbul region coals. These lignitic coals generally have relatively low ash (lo%), and higher levels of calorific values over 5000 kcali kg. The multi-gravity separator, a new fine size gravity separation equipment, was tasted to evaluate its potential for the desulfurization of these low-rank coals. Systematic tests conducted on two different samples of minus 1 mm size indicate that despite the finely distributed nature of coal and relatively small difference between coal and its associated gangue minerals, the degree of pyritic sulfur removal is h5.7% and 85.9’/;, respectively, for the coals.
97104400 at elevated
Devolatilization of Yallourn (Australia) pressure in an entrained flow reactor
brown
coal
Mathews, J. F. DGMK Tagungd~er., 1997, 9703, (Proceedings ICCS ‘97, Volume 2), 629-632. The devolatilization hehaviour of Yallourn brown coal was studied in a pressurized drop-tube furnace. Coal particles of 37-53 ,,rn size were devolatilized at pressures of 100 and SO0 kPa. The experiments were carried out at temperatures of 873, 1073, and 1273 K and rcsidcncc times were varied from 0.2-2 s. The particle heating and cooling rates were in the order of 106 and 105 K/s, respectively. Ash was used as a tracer to calculate weight loss due to devolatilization. Total gas and tar yields were also measured. The weight loss was found to increase with an increase in devolatilization temperature. Increasing the pressure not only increases the residence time required to achieve a given level of weight loss. hut also reduces the total loss attainable at a particular temperature. As the gas pressure external to the particle is increased from 100 kPa to 500 kPa. the yield of tar, as the percentage of daf coal, obtained during devolatilization decreases, whereas the total gas yield increases.
97104401 drop-tube
Devolatilization furnace
of Yallourn
coal in a pressurized
Cod Cmf.. lYY6. 13. ( I). XYeasmin, H. et al. Proc. Anmr. Int. iWshurg/~ 13. At the Co-operative Research Center for New Technologies for Power Generation from Low-Rank Coal, a pressurized drop-tube furnace has hcen built to study the details of the kinetic behaviour of low rank coal during devolatilization, gasification and combustion. The facility can be operated at pressures and temperatures up to 1600 kPa and 1673 K. respectively. The reaction time can he varied from ahout 20 ms to seveml seconds. A
So/id
97104369
fuels
(preparation)
Bed blending
of coals
Ruth, M. et al. peel. 1997. 76, (13). 1297-1300. Bed blending aims to improve the quality and consistency of the blended material. However, variations sometimes occur in beds, and so monitoring is necessary. Automatic petrographic techniques have been developed to determine the distribution of low-grade filler material within coal layers and the major components in blend samples. The major cause of variations in the properties of coke produced from coal blends was identified as uneven distribution of filler. Consequently, changes were made to bed construction which improved the consistency of the chemical and rheological properties of the blend and the physical properties of the coke.
97104390 fuels
Beneficiation
of coal fines toward
Beneficiation
of low grade anthracites
Lee, J.-J. et al. Chawon Risaikritzg.. 1996, 5, (2). 45-51. (In Korean) Sulfur levels of approximately 0.3-7s are found in South Korean coals. When burned, the sulfur may cause air pollution problems, as well as acid rain. The government decided to strengthen the environmental protection policy for the coal-fired plants, applied from I January 1999. This study was carried out to remove the S and mineral matters in the samples using wet magnetic separator and oil agglomeration apparatus. The results showed that the total sulfur removal from Kangung coal sample was 60.8% and 82.6% combustible recovery. For the results of oil agglomeration tests, comhustihle recovery, ash and sulfur removal from Mare coal sample were 98.0. 70.Y and 95.7%, respectively.
Biodesulfurization of Turkish Iignites. 2. Microbial 97104392 desulfurization of Mengen lignite by the mesophilic microorganism Rhodococcus rhodochrous Durusoy, T. EI al. Fuel, 1997, 76, (4). 341-344. Presents a study into the effects of substrate type in the growth medium. 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 of Rhodococcus rhodochrorrs. The highest reduction of organic sulfur forms was 27.1% using sodium acetate as the substrate. Sulfate sulfur could he completely 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 found when the substrate was sodium acetate.
Brown coal research in Slovakia from the point of 97104393 view of application of advanced cleaning technologies Turcaniova, L. et al. Proc. Annu. Inf. Pirrshurgh Coal Conf., 1996, 13, (2), 91 l-915. The scientific programme of the joint Slovak-American project of brown coal research in Slovakia is presented from the point of view of application of advanced cleaning technologies. The objective is to examine advanced clean coal technology under Slovakian conditions. At present the perspectives of brown coal mining are being assessed. The material and technological characteristics of the coal processing will be assessed together with evaluation of the perspective areas of use. Depending on the coal types, physical, chemical and biological processing technologies will he evaluated. The paper discusses the chemical characterization of different forms of as well as the Moesshauer spectroscopy of coal samples.
97104394 Changes in moisture parameters coals on low-temperature heat treatment
of higher
rank
Dunlop, N. F. and Johns, R. B. DGMK 7ag~ngshe~., 1997, 9702, (Proceedings ICCS. ‘97, Volume 1). 377-380. Marked changes in moisture equilibrium values at short treatment limes were induced by a series of low temperature heat treatments of three different coals in a flow of moist air. Changes in the chemical functional groups, within and on the surface of the coal were followed by DRIFT and MAS “C SSNMR spectroscopy. The formation of C-O single bonds is a major pathway of oxidation in early reactions. These lead to the C=O functionalities conventionally observed The progressive chemical changes observed may explain in part the observed variations in the moisture uptake and equilibrium moisture content of all three coals reported.
382
Fuel and Energy Abstracts
November
1997
kinetics
of a gas-promoted
oil
Zlhang, F. and W’heelock, T. D. Proc,. Anne. Int. Pirtsh~~$ Coral Conf:. 1996, 13, (I), s47-552. Gas-promoted oil agglomeration process kinetics were investigated by monitoring the change in the turbidity of an aqueous particle suspension as the particles were agglomerated with heptane in a closed tank fitted with baffles and an agitator. Measured amounts of air and heptane were added to a suspensions of Pittsburgh No. 8 coal under vigorous agitation. The subsequent rate of change of particle concentration was taken to he an indication of the rate of agglomeration. The rate was proportional to the particle number of concentration raised to a power and dependent on agitator speed and the amounts of air and oil added.
clean ecological
Sciazko, M. el a/. DGMK Tugu+$~r., 1997, Y702, (Proceedings ICCS ‘97, Volume I), 539-542. Ecological and smokeless fuels are prepared by granulation and hriquetting. The effective way to reduce noxious emissions from residential heating sector is elimination of coal from direct use; substituting it by ecolological solid fuels based on hard coal. Several such technologies were developed in the Institute for Chemical Processing of Coal (IChPW). The technologies hased on coal fines as a raw material permit the preparation of lowemission coal briquettes and granules of considerably higher ecological quality. even than high grade coal. The market for hriquetted solid fuels in Poland is estimated to he between I and 2 million t/year.
97104391
97104395 Coal beneficiation aaalomeration orocess
97104396 Coal properties water drying method
of upgraded
low-rank
coals by hot
Ohki. A. et al. DGMK Ta~~ng.she~., lYY7. 0702. (Proceedings ICCS ‘Y7. Volume I), 4X7-490. Hydrothermal treatment of various coals of different rank, at lSO~3Sll C in an autoclave, was carried out. With rising heat-treatment temperature (HTT). The hygroscopicity of low-rank coals gradually decreased. The content of carhoxyl group greatly decreased hy the treatment. hut a Its\ remarkable change in the content of hydroxyl group as well as that in the specific surface area of coal was noted.
97104397 Conditions for processing and dewatering slurries at Nagolchenskaya Central beneficiation plant
of coal
Muatafin, L. D. and Pul’chev. A. D. U$’ Ukr., lYY7, (2-3). 3X-411. (In Russian) In order to increase the efficiency of coal suspension capture at Nagolchenskaya Central beneficiation plant, a rearranged set ot hydrocyclones and conveyor vacuum filters were implemented. These mcasurcc decreased the solid content of recycled water to 100-120 kg/m’ and decreased the amount of solids discharged to settlers by 40%.
97104398
Desulfuriration
of coal using borax
Yaman, S. and Kucukbayrak, S. Proc. Amw. Int. P~rrshftr;qh Ccw/ (‘OH/:, 1996, 13, (l), 216-220. Varying amounts of solid borax was mixed with high sulfur Turkish lignite. These mixtures were then subjected to various oxydesulfurization processes. Effects of amount of borax, temperature and partial pressure of oxygen on sulfur removal and coal recovery were investigated in the ranges of O.h25IS.000 g for 5 g lignite, 423-498 K and O.O-I..5 MPa. respectively.
97104399 Desulfurization gravity separator
of low-rank
Turkish
coals by multi-
Aydin, M. E. et al. Proc. Anm. Int. Pitfshurgh Cm/ LhnJ:. IYYh. 1.3. ( I ), 437-442. High moisture contents (average 3.5%). high volatile matter value\ (average 45%). and, more importantly. high levels of sulfur in the range of I-5’;, are features of Istanbul region coals. These lignitic coals generally have relatively low ash (lo%), and higher levels of calorific values over 5000 kcali kg. The multi-gravity separator, a new fine size gravity separation equipment, was tasted to evaluate its potential for the desulfurization of these low-rank coals. Systematic tests conducted on two different samples of minus 1 mm size indicate that despite the finely distributed nature of coal and relatively small difference between coal and its associated gangue minerals, the degree of pyritic sulfur removal is h5.7% and 85.9’/;, respectively, for the coals.
97104400 at elevated
Devolatilization of Yallourn (Australia) pressure in an entrained flow reactor
brown
coal
Mathews, J. F. DGMK Tagungd~er., 1997, 9703, (Proceedings ICCS ‘97, Volume 2), 629-632. The devolatilization hehaviour of Yallourn brown coal was studied in a pressurized drop-tube furnace. Coal particles of 37-53 ,,rn size were devolatilized at pressures of 100 and SO0 kPa. The experiments were carried out at temperatures of 873, 1073, and 1273 K and rcsidcncc times were varied from 0.2-2 s. The particle heating and cooling rates were in the order of 106 and 105 K/s, respectively. Ash was used as a tracer to calculate weight loss due to devolatilization. Total gas and tar yields were also measured. The weight loss was found to increase with an increase in devolatilization temperature. Increasing the pressure not only increases the residence time required to achieve a given level of weight loss. hut also reduces the total loss attainable at a particular temperature. As the gas pressure external to the particle is increased from 100 kPa to 500 kPa. the yield of tar, as the percentage of daf coal, obtained during devolatilization decreases, whereas the total gas yield increases.
97104401 drop-tube
Devolatilization furnace
of Yallourn
coal in a pressurized
Cod Cmf.. lYY6. 13. ( I). XYeasmin, H. et al. Proc. Anmr. Int. iWshurg/~ 13. At the Co-operative Research Center for New Technologies for Power Generation from Low-Rank Coal, a pressurized drop-tube furnace has hcen built to study the details of the kinetic behaviour of low rank coal during devolatilization, gasification and combustion. The facility can be operated at pressures and temperatures up to 1600 kPa and 1673 K. respectively. The reaction time can he varied from ahout 20 ms to seveml seconds. A