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00939 Desulfurization of high-sulfur coal in cement kiln
01
Solid fuels (preparation)
Changes in the moisture content of brown coal during mining and processing ,and their possible effect on results of beneficiation
98100934
Novacek, .I. et al. Lrhli-Rudy-Geol. Pruzkum, 1997,4, (Z), 50-54. (In Czech) The moisture content decrease in various types of as-mined brown coal during drying was investigated. In laboratory experiments, drying was done in air at 19.5-22°C. Dependence of the moisture content and bulk density on the drying time was evaluated. The bulk density is an important factor for coal beneficiation.
Coal cleaning in a Meg-Mill 98mo935 Oder, R. R. et al. Proc. Annu. Int. Pittsburgh Coal Conf., 1995,12,306-311. The technical feasibility of preparing low ash and low sulfur coals by employing dry magnetic separation to treat the internal circulation of airswept pulverizers preparing pc grin+ coal for direct firing has been demonstrated by results of previous studies. More recent experimental results are presented here, extending the earlier work. The effects of treating more of the mill’s internal circulation than was previously possible has been studied. The ParaTrap magnetic separator can be retrofitted to existing pulverizers keeping capital costs low. A preliminary engineering evaluation indicates that a 1600 MW, power plant burning washed coal from Northern Appalachia can make an annual saving of as much as $4,000,000 cleaning raw coals in the Mag-Mill. Coal thermosolvolysis 98lOO936 Jasienko, S. and Gerus-Piasecka, I. Chemical Fiz. Weglu, 1995, 331-348. Politechniki (In Polish). Edited by Jasienko, S.: _Oficyna Wydawnicza Wroclawskiej, Wroclaw, Poland. The thermosolvolysis process is reviewed-thermobitumen formation and its kinetics, properties and structure of group components from thermosolvolysis, and their effect on coking properties and coke texture. 96100937
Desulfurization of coal using formic acid
Wang, G. et al. Proc. Annu. Int. Pittsburgh Coal Conf., 1995, 12, 481-486. A pre-oxidized Illinois Basin coal, IB 108, was desulfurized with formic acid. A factorial design with four pro 3 ss variables (temperature, reaction time, amount of formic acid and amohnt of H202 used in pre-oxidation) was used to study the process. Maximum total sulfur removal of 74% was achieved by pre-treatment of 5 g coal with 10 ml H202 followed by reaction with 7.5 ml formic acid at 500°C in a 300 ml batch reactor. The level of desulfurization that may be obtained with subsequent chemical or thermal treatments, was significantly enhanced by oxidation with H202.
Desulfurization of high-sulfur coal during hydropyrolysis. II. Effects of reaction parameters on desulfurization in hydropyrolysis
98lOO936
Chen, H. et al. Ranliao Huaxue Xuedao, 1997, 25, (5). 404-409. (In Chinese) A fixed-bed reactor was used to investigate the desulfurization of Hongmiao lignite during hydropyrolysis. The effects of various parameters including gas velocity, pressure, heating rate and residence time on the sulfur contents of char, tar, desulfurization and sulfur distributions in gas, char and tar were studied. Desulfurization was improved by increasing gas velocity and sulfur contents in char were reduced substantially. Higher pressure was found to enhance the hydrodesulfurization reactions between hydrogen and sulfur in coal. Lower heating rate is also beneficial to sulfur removal. Longer residence time enable more hydrogen to diffuse through coal particles and react thoroughly with sulfur in coal. Mass transfer was another important factor influencing desulfurization. The sulfur distributions in tar were largely unaffected by these kaction parameters.
9ai00939
Desulfurization of high-sulfur coal in cement kiln
96100940
Desulfuriration
Xie, J. et al. W&an Gongye Darue Xuebao, 1996, 18, (2), 17-20. (In Chinese) The paper studies the desulfurization process with CaCO3, BaCOS, and Sr(N0j)2 in the combustion of high-S coal in a cement kiln, including the forms of the S conversion, was studied by DTA and XRD, and the desulfurization efficiency of CaCO 3, BaCO;, and Sr(N03)2 were determined by elemental analysis.
of Tabas cpal by Thiobacillus
ferrooxidans Tabatabae, M. et al. Miner. Eng., 1996, 9, (9), 1001-1005. An average sulfur content of 1.5% is found in Tabas coal contained in the Parvadeh coalfield. A sample of high sulfur coal has been used in the desulfurization programme, which included tests using Thiobacillus ferrooxidans in two different media. These were characterized using IR spectroscopy and total sulfur content reduction was measured using a Lecoanalyser. The reduction in sulfur content depends on the media employed. The pyritic sulfur was reduced by 59.8% in medium 9/10K and by 65% in medium TB 15 days following innoculation.
Development and characteristics of coal beneficla96KlO941 tion in the Western Ukraine Polulyaka, A. D. et al. Ugol’Ukr., 1996, (12), 8-10. (In Russian) Discusses properties of coals of the western Donets and Lvov-Volyn and a need for proper beneficiation methods.
88
Fuel and Energy Abstracts
March 1996
basins
96100942
Development and use of non-Russian and Russian modular beneficiation installations
Linev, B. I. el al. Ugol’1996, (5), 48-51. (In Russian) Modular installations for coal separation and briquetting
are reviewed.
Development of a macroscopic coal preparation simulator for the National Energy Modelling System
9aIoo943
Paul, A. D. and Ramesh, R. Proc. Annu. Int. Pittsburgh Coal Conf., 1995, 12, 492-497. Conventional and advanced coal preparation can be simulated by a macroscopic engineering model proposed as part of the capability of the US Department of Energy’s National Energy Modelling System. This model needed to be flexible to predict coal quality improvements not only with current technology, but with future technological advancements forecasted up to 2015. Conventional preparation was modelled based on available coal washability data to capture individual seam characteristics. Advanced preparation was modelled based on a combination of conventional and advanced cleaning and a series of assumptions regarding ash rejection, combustible matter recovery, and pyrite rejection in the advanced cleaning section. The model estimates product characteristics, yields, and associated cleaning costs produced by conventional and advanced preparation for a given demand. These characteristics were then used within the NEMS project to select a product coal able to meet national demands at minimal cost. 96100944 Developments in the field of technology beneficiation of high-ash coals
and
Nikitin, 1. N. Woks Khim., 1997, (7), 6-8. (In Russian) The development of coal treatment in the Ukraine is reviewed, including jigging of coal slurries with application of selective flocculation methods; flocculation-gravity separation of coals; flocculation-flotation of coal slurries; flotation with a highly-efficient reagent (petroleum refining residues); high-yield flotation machine FM-25; deep treatment of intermediate product; intensification of coal dewatering with chemical agents; ecologically clean coal beneficiation; and protective coating for prevention of coal from weathering and oxidizing during its storage in open areas.
Dewatering of fine coal using hyperbaric filter 9aloo945 Yang, J. et al. Proc. Annu. Int. Pittsburgh Coal Conf., 1995, 12, 333-338. Conventional dewatering equipment cannot easily achieve the removal of moisture from ultra-fine clean coal to below 20% level. A couple of dewatering approaches which were found to be effective in providing filter cakes containing less than 20% moisture are detailed. They involve the addition of metal ion-surfactant, and split size dewatering of coal without adding a reagent. 90lOO946
Effect of heating rate on the final volatile yield in pulverized coal devolatilization
Zhu, Q. et al. Harbin Gongye Daxue Xuebao, 1996, 28, (3), 35-39. (In Chinese) Eighteen different coal types were studied at different heating rates in a thermobalance to determine their final volatile yield. The results show that the final volatile yield mainly depends on pulverized coal temperature and heating rate and is insensitive to coal particle diameter. The paper provides calculation equations of the final volatile yield. 96100947
Effect of mine water salinity on flotation of coal slurries from the Budryk mine
Iskra, J. et al. Zesz. Nauk. Politech. Slask., Gom., 1996, 231, 237-252. (In Polish) Results of investigations of the influence of mine water salinity on the fine coal flotation from the Budryk mine are reported. The water salinity improves the flotation kinetics and reduces the flotation reagents consumption. 98lOO946
Amasra coal
The effect of premixing on the floatation of oxidized
Piskin, S. and Akguen, M. Fuel Process. Technol., 1997, 51, (l/2), l-6. Oxidized Amasra coal containing high quantities of inorganic materials were examined under laboratory conditions to ascertain the factors affecting its floatation efficiency. The Amasra coal samples were oxidized by exposing them to atmospheres for a long time with the aim of obtaining coal having a lower ash content. Premixing is applied to condensed pulp containing 60% coal and 40% water to remove the oxidized layer on the coal surface. The oxidized layer is removed as a result of friction between particles during mixing. Some relations were obtained between frothing period, calorific value, combustible matter recovery, and ash content. Also examined was the relation between premixing and floatation efficiency was another subject. The effect of oxidized coal on floatation was also examined after oxidized coal was exposed to thermal treatment in inert milieu. At the end of an average frothing period of 20-25 min, it was observed that the quantity of product increased and the ash content in the product reached a minimum value. At the same time, the calorific value of the coal and the recovery of combustible matter reached their highest value.
Solid fuels (preparation)
Changes in the moisture content of brown coal during mining and processing ,and their possible effect on results of beneficiation
98100934
Novacek, .I. et al. Lrhli-Rudy-Geol. Pruzkum, 1997,4, (Z), 50-54. (In Czech) The moisture content decrease in various types of as-mined brown coal during drying was investigated. In laboratory experiments, drying was done in air at 19.5-22°C. Dependence of the moisture content and bulk density on the drying time was evaluated. The bulk density is an important factor for coal beneficiation.
Coal cleaning in a Meg-Mill 98mo935 Oder, R. R. et al. Proc. Annu. Int. Pittsburgh Coal Conf., 1995,12,306-311. The technical feasibility of preparing low ash and low sulfur coals by employing dry magnetic separation to treat the internal circulation of airswept pulverizers preparing pc grin+ coal for direct firing has been demonstrated by results of previous studies. More recent experimental results are presented here, extending the earlier work. The effects of treating more of the mill’s internal circulation than was previously possible has been studied. The ParaTrap magnetic separator can be retrofitted to existing pulverizers keeping capital costs low. A preliminary engineering evaluation indicates that a 1600 MW, power plant burning washed coal from Northern Appalachia can make an annual saving of as much as $4,000,000 cleaning raw coals in the Mag-Mill. Coal thermosolvolysis 98lOO936 Jasienko, S. and Gerus-Piasecka, I. Chemical Fiz. Weglu, 1995, 331-348. Politechniki (In Polish). Edited by Jasienko, S.: _Oficyna Wydawnicza Wroclawskiej, Wroclaw, Poland. The thermosolvolysis process is reviewed-thermobitumen formation and its kinetics, properties and structure of group components from thermosolvolysis, and their effect on coking properties and coke texture. 96100937
Desulfurization of coal using formic acid
Wang, G. et al. Proc. Annu. Int. Pittsburgh Coal Conf., 1995, 12, 481-486. A pre-oxidized Illinois Basin coal, IB 108, was desulfurized with formic acid. A factorial design with four pro 3 ss variables (temperature, reaction time, amount of formic acid and amohnt of H202 used in pre-oxidation) was used to study the process. Maximum total sulfur removal of 74% was achieved by pre-treatment of 5 g coal with 10 ml H202 followed by reaction with 7.5 ml formic acid at 500°C in a 300 ml batch reactor. The level of desulfurization that may be obtained with subsequent chemical or thermal treatments, was significantly enhanced by oxidation with H202.
Desulfurization of high-sulfur coal during hydropyrolysis. II. Effects of reaction parameters on desulfurization in hydropyrolysis
98lOO936
Chen, H. et al. Ranliao Huaxue Xuedao, 1997, 25, (5). 404-409. (In Chinese) A fixed-bed reactor was used to investigate the desulfurization of Hongmiao lignite during hydropyrolysis. The effects of various parameters including gas velocity, pressure, heating rate and residence time on the sulfur contents of char, tar, desulfurization and sulfur distributions in gas, char and tar were studied. Desulfurization was improved by increasing gas velocity and sulfur contents in char were reduced substantially. Higher pressure was found to enhance the hydrodesulfurization reactions between hydrogen and sulfur in coal. Lower heating rate is also beneficial to sulfur removal. Longer residence time enable more hydrogen to diffuse through coal particles and react thoroughly with sulfur in coal. Mass transfer was another important factor influencing desulfurization. The sulfur distributions in tar were largely unaffected by these kaction parameters.
9ai00939
Desulfurization of high-sulfur coal in cement kiln
96100940
Desulfuriration
Xie, J. et al. W&an Gongye Darue Xuebao, 1996, 18, (2), 17-20. (In Chinese) The paper studies the desulfurization process with CaCO3, BaCOS, and Sr(N0j)2 in the combustion of high-S coal in a cement kiln, including the forms of the S conversion, was studied by DTA and XRD, and the desulfurization efficiency of CaCO 3, BaCO;, and Sr(N03)2 were determined by elemental analysis.
of Tabas cpal by Thiobacillus
ferrooxidans Tabatabae, M. et al. Miner. Eng., 1996, 9, (9), 1001-1005. An average sulfur content of 1.5% is found in Tabas coal contained in the Parvadeh coalfield. A sample of high sulfur coal has been used in the desulfurization programme, which included tests using Thiobacillus ferrooxidans in two different media. These were characterized using IR spectroscopy and total sulfur content reduction was measured using a Lecoanalyser. The reduction in sulfur content depends on the media employed. The pyritic sulfur was reduced by 59.8% in medium 9/10K and by 65% in medium TB 15 days following innoculation.
Development and characteristics of coal beneficla96KlO941 tion in the Western Ukraine Polulyaka, A. D. et al. Ugol’Ukr., 1996, (12), 8-10. (In Russian) Discusses properties of coals of the western Donets and Lvov-Volyn and a need for proper beneficiation methods.
88
Fuel and Energy Abstracts
March 1996
basins
96100942
Development and use of non-Russian and Russian modular beneficiation installations
Linev, B. I. el al. Ugol’1996, (5), 48-51. (In Russian) Modular installations for coal separation and briquetting
are reviewed.
Development of a macroscopic coal preparation simulator for the National Energy Modelling System
9aIoo943
Paul, A. D. and Ramesh, R. Proc. Annu. Int. Pittsburgh Coal Conf., 1995, 12, 492-497. Conventional and advanced coal preparation can be simulated by a macroscopic engineering model proposed as part of the capability of the US Department of Energy’s National Energy Modelling System. This model needed to be flexible to predict coal quality improvements not only with current technology, but with future technological advancements forecasted up to 2015. Conventional preparation was modelled based on available coal washability data to capture individual seam characteristics. Advanced preparation was modelled based on a combination of conventional and advanced cleaning and a series of assumptions regarding ash rejection, combustible matter recovery, and pyrite rejection in the advanced cleaning section. The model estimates product characteristics, yields, and associated cleaning costs produced by conventional and advanced preparation for a given demand. These characteristics were then used within the NEMS project to select a product coal able to meet national demands at minimal cost. 96100944 Developments in the field of technology beneficiation of high-ash coals
and
Nikitin, 1. N. Woks Khim., 1997, (7), 6-8. (In Russian) The development of coal treatment in the Ukraine is reviewed, including jigging of coal slurries with application of selective flocculation methods; flocculation-gravity separation of coals; flocculation-flotation of coal slurries; flotation with a highly-efficient reagent (petroleum refining residues); high-yield flotation machine FM-25; deep treatment of intermediate product; intensification of coal dewatering with chemical agents; ecologically clean coal beneficiation; and protective coating for prevention of coal from weathering and oxidizing during its storage in open areas.
Dewatering of fine coal using hyperbaric filter 9aloo945 Yang, J. et al. Proc. Annu. Int. Pittsburgh Coal Conf., 1995, 12, 333-338. Conventional dewatering equipment cannot easily achieve the removal of moisture from ultra-fine clean coal to below 20% level. A couple of dewatering approaches which were found to be effective in providing filter cakes containing less than 20% moisture are detailed. They involve the addition of metal ion-surfactant, and split size dewatering of coal without adding a reagent. 90lOO946
Effect of heating rate on the final volatile yield in pulverized coal devolatilization
Zhu, Q. et al. Harbin Gongye Daxue Xuebao, 1996, 28, (3), 35-39. (In Chinese) Eighteen different coal types were studied at different heating rates in a thermobalance to determine their final volatile yield. The results show that the final volatile yield mainly depends on pulverized coal temperature and heating rate and is insensitive to coal particle diameter. The paper provides calculation equations of the final volatile yield. 96100947
Effect of mine water salinity on flotation of coal slurries from the Budryk mine
Iskra, J. et al. Zesz. Nauk. Politech. Slask., Gom., 1996, 231, 237-252. (In Polish) Results of investigations of the influence of mine water salinity on the fine coal flotation from the Budryk mine are reported. The water salinity improves the flotation kinetics and reduces the flotation reagents consumption. 98lOO946
Amasra coal
The effect of premixing on the floatation of oxidized
Piskin, S. and Akguen, M. Fuel Process. Technol., 1997, 51, (l/2), l-6. Oxidized Amasra coal containing high quantities of inorganic materials were examined under laboratory conditions to ascertain the factors affecting its floatation efficiency. The Amasra coal samples were oxidized by exposing them to atmospheres for a long time with the aim of obtaining coal having a lower ash content. Premixing is applied to condensed pulp containing 60% coal and 40% water to remove the oxidized layer on the coal surface. The oxidized layer is removed as a result of friction between particles during mixing. Some relations were obtained between frothing period, calorific value, combustible matter recovery, and ash content. Also examined was the relation between premixing and floatation efficiency was another subject. The effect of oxidized coal on floatation was also examined after oxidized coal was exposed to thermal treatment in inert milieu. At the end of an average frothing period of 20-25 min, it was observed that the quantity of product increased and the ash content in the product reached a minimum value. At the same time, the calorific value of the coal and the recovery of combustible matter reached their highest value.