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Bituminous coal pyrolysis tar as feedstock for carbon black production — a preliminary study
01 Solid fuels (derived solid fuels) information. The appearance of the coal slurry ash detector provides the new method for resolving the problems above. This paper studies how to increase the production rate and decrease the reagent consumption through the optimizing control under the premise of the accepted concentrated ash. 02/01812 The production of ultra clean coal by chemical demineralisation Steel, K. M. and Patrick, J. W. Fuel, 2001, 80, (14), 2019-2023. A high-volatile UK coal, with a particle size of <500 pm, an ash content of approximately 7.9% by weight and a sulphur content of 2.6% by weight, was treated with aqueous HF followed by aqueous HNOa. The reaction residence time and temperature for both treatments were 3 h and 65°C respectively. HF reduces the ash content to approximately 2.6% by weight. The remaining ash largely consists of fluoride compounds such as AFa, NaAF4, CaFz and MgFa, which form during leaching, and pyrite (Fe&), which does not react with HF, HNOs then further reduces the ash content to approximately 0.6% by weight, by dissolving fluoride compounds and the Fe present as Fe&, The remaining ash consists largely of unreacted Fe&, which is encapsulated in the coal structure. This investigation also showed that HNOa, only reacts with Fe& above a particular HNOs concentration, which suggests that it is consumed preferentially, and to a certain extent, with the organic cola structure. The final sulphur content following treatment with HF and HNOa was 1.4% by weight. 02/01813 The role of activation in the chemical treatment of coal Turcaniova, L. Ed al. Proc. - Annu. Int. Pittshurglr Cocrl Conf., 2000, (17), 2218-2221. This paper presents a new approach concerning the interconnection of coal treatment science and mechanochemical processes. The mechanochemical procedure of alkaline treatment, the so-called GACL (grinding aq. caustic leaching) procedure of coal pretreatment was evaluated in the complex scheme of chemical and pharmaceutical use of coal components. The treatment procedure for a complex use of coal mass is complemented by a low temperature procedure of alkaline coprocessing for preparation of activated carbon and alternative technology gas based on additional use of carbonaceous wastes. The approach to a complex use of coal is presented using an example of Slovak brown coal from Novaky. In the pre-treatment process, so called GACL procedure, it is possible to achieve 90% efficiency of arsenic removal, 60% efficiency of desulphurization and 2.5-fold increase in the content of humic acids. The extension of rare organic substances enables to obtain derivates of kaurene acid, azulene and environmental standards, i.e. naphthalene, pyridine, benzene and biphenyl.
Economics,
business,
marketing,
policy
02/01814 Coal information for the 21st century Finkelman, R. B. er al. Proceedings - Annuul Interncrtional Pittsburgh Coul Collference, 2000, (I 7), 7-l 3. The US Geological Survey (USGS) has developed a new series of databases and products to aid the coal community in obtaining the information needed to address technological, economic, and environmental issues in the 21st century. The USGS in co-operation with the Electrical Power Research Institute and their member utilities, the Department of Energy, coal mining companies, and about 15 state agencies, are collecting and analysing approximately 1000 samples of US coal. This project will generate a broad array of reliable and accurate information on coals currently being mined and burned. The USGS in co-operation with more than 40 coal producing countries, has also initiated an international coal quality database that will contain accurate analyses of carefully collected samples from major coalproducing regions around the world. The data from these projects will be available through GEODE, a web-based interactive GIS application. These data will also be included in decision support systems that help decision-makers better assess economic and technological risks and cost effectively limit environmental degradation. 02/01815 EPRl’s view of global coal technologies for the new century Courtright, H. and Dalton, S. Proceedings - Annuul Interna/ionul Pirtshurgh Coral Conference, 2000, (I 7), 14-24. Coal use is under attack in many developed countries, and is faced with ever-tightening environmental restrictions and concerns about COz emissions. For many of the world’s countries with large percentages of the population, coal is the fuel that will be used for new power plants, Even in many developed countries, coal will continue to fuel large percentages of generation. Using coal efficiently and in an environmentally responsible manner will be a challenge for technological and 238
Fuel and Energy Abstracts
July 2002
politics of the next century. Coal use will change in the next few decades, including short-term change such as the use of more efficient ultrasupercritical boilers to longer term refining of coal to produce a range of energy and chemical outputs. A portfolio of the needed developments and demonstrations that support the long term vision, and the relative merits of these technologies are outlined. 02/01816 Strategic considerations for clean coal R&D McMullan, J. T. er al. Energy Policy, 2001, 29, (6). 441-452. While present interest in coal-fired power generation is centred on the with new natural-gas-fired power stations developing countries, predominating in the developed world, in the long term coal will return to being the fuel of choice for power generation for much of the world. To minimize the global impact of coal use it is essential, therefore, that coal technologies are developed that are efficient, clean and economically attractive. Techno-economic analyses of the options for coal presented together with a strategic overview of potential lines of development. The broad conclusions are that new coal plant will not be truly competitive with natural gas until the price of gas increases to about 3.3 euro/GJ, compared with a coal price of 1.3 euro/GJ. Present state-of-the-art pulverized coal-fired plant is close to its optimum techno-economic performance and further improvements depend on the development of cost-effective super-alloys. However, there are good opportunities to increase the efficiency of coal use to greater than 50% (LHV basis) using gasification-based power generation cycles. Unless credit is given for the much lower emissions provided by these cycles, the pulverized coal and pressurized fluidized bed combustion will remain the most economic options. 02/01817 Trends and novel technologies in the coal industry in the USA Salyaev, A. V. Ugol’ Ukrainy, 2001. (7).52-55. (In Russian) A successful development of the coal industry in the USA as the result of the high technological involvement is discussed.
Derived
solid fuels
02/01818 Apparatus and method for production of coalwater paste fuel for pressurized fluidized bed boilers Takesaki, H. e/ crl. Jpn. Kokai Tokkyo Koho JP 2001 330.238 (Cl. F23K1/02). 30 Nov 2001, Appl. 2000:150,101, 22 May 2000. 6. (In Japanese) The title apparatus comprises means for crushing raw coal from a bunker through a ball mill, means for wet grinding the coal grains with water in a 2nd ball mill to form a coal slurry, means for mixing the coal slurry and additional water and a desulphurizing agent, and means for further grinding the coal slurry and pumping it through a spray nozzle into the pressurized fluidized bed boilers. 02/01819 Bituminous coal pyrolysis tar as feedstock for carbon black production - a preliminary study Pradhan, B. K. and Eser, S. Proc. - Anmr. Inr. Pitrshurgh Coal Con/ _ 2000, (I 7), 337-365. A steadily decreasing metallurgical coke production m byproduct coke ovens in the USA, namely the strong demand for coal tar and coal-tar derived carbon precursors calls for exploring acceptable alternative processes to separate coal tar production from the parent process of coke-making in byproduct coke ovens. As a possible alternative, steam pyrolysis of bituminous coals was proposed for the production of raw coal tar, which can be further processed to produce coal tar products with desired properties. In this study, steam pyrolysis of four different coal samples (Arch, Amerikohl, Splash dam and Pocahontas #3) was carried out in a tubular reactor. Steam pyrolysis experiments were conducted at four different temperatures (500, 600, 700 and 800°C) on all the samples using a steam flow rate of 3 g/mm at a constant heating rate of lD”C/minimum The effects of heating rate and steam flow rate on the product yields were also studied for different coal samples. Changes in pyrolysis temperature, heating rate, and steam flow rate strongly affected the tar yields and composition. In general, an intermediate pyrolysis temperature (6OO”C), an intermediate steam flow rate (3 g/min), and a moderate heating rate (lO”C/min) gave the highest tar yields. Among the coal samples, Pocahontas #3 gave a much lower tar yield (3-j% wt on a dry-ash-free basis) than those of the other samples that ranged between 7 and 16 wt% on daf basis, These tar yields are much higher than that obtained in byproduct coke ovens (2-3%). The tar samples obtained were characterized by hightemperature simulated distillation using gas chromatography (HT SimDis GC) with a capillary column. The atmosphere equivalent boiling point distribution of different coal tar samples were detected by using this method. A coal tar oil sample used for carbon black production was also analysed by HT Sim-Dis GC. The atmospheric Gs oil and light
07 gas oil fractions are the major constituents (90%) of this coal tar oil. Among the tar collected from the four different coal samples, Pocahontas tar contains the least proportion of these two fractions, while Arch and Amerikohl tars have the greatest abundance of these fractions followed by the Splash Dam coal tar. Steam pyrolysis of Arch and Amerikohl coals would produce raw tars with high yields of carbon black oils. 02/01820 Briquetting method for biomass coal and its influencing factors Xu, K. et al. Hunnjing Kexue, 2001, 22, (4) 81-85. (In Chinese) A briquetting mechanism using the linkage function of biomass fibre was established for briquetting of biomass coal. The effect of different coal, briquetting pressure, biomass shape and content, and water content on the briquetting performance was studied. The results showed that the briquetting method was suitable for varied kinds coal and biomass. The briquette mechanism performance was improved with the increasing of biomass content, with a reasonable low limitation Pure biomass also could be briquetted. The briquetting of -15%. pressure which could consolidate the linkage of biomass fibre was no > 120 MPa. There would be a negative effect at too high pressure. Increasing biomass content and decreasing pressure at certain degree could offset the negative effect of water content significantly, with a permissive limitation over 10% for Datong coal. 02/01821 Characterization of chars from biomass-derived materials: pectin chars Sharma, R. K. el al. Fuel, 2001, 80, (12), 1825-1836. The effect of pyrolysis conditions on the yield and composition of char from pectin was studied. Pectin is a component of the carbohydrate fraction of biomass-derived materials. The pyrolysis was done at atmospheric pressure under oxidative and non-oxidative (inert) atmospheres and at temperatures ranging from 150 to 550°C. The volatile product was analysed by gas chromatography/mass spectrometry (GCIMS). The solid product, i.e. char, was characterized by solid-state 13C nuclear magnetic resonance (NMR) and Fouriertransform infrared (FTIR) spectroscopy. The char was also analysed for its elemental composition and surface area. The surface morphology of char was studied by scanning electron microscopy (SEM). The results were compared to those from chlorogenic acid (CA), a component of the phenolic fraction of biomass-derived materials. The behaviour of pectin was similar to that of CA. For both pectin and CA, the char yield decreased with increasing temperature before levelingoff at ca. 20% of the starting substrate in non-oxidative runs. In oxidative runs, the char yields from both substrates became negligible at 550°C. NMR analysis indicated that the aromatic character of char increased as the pyrolysis temperature increased. The oxygen functionality was progressively lost and the resonance bands corresponding to carbonyl groups mostly disappeared above 350°C. FTIR analysis also suggested the loss of hydroxyl and carbonyl groups from chars at high temperatures. The H/C and O/C ratios of chars decreased continuously with increasing temperature. The oxidative chars showed characteristics essentially similar to those of the non-oxidative chars. The surface area of char was negligible at low temperatures, but increased dramatically to a maximum of 70 m2 g -’ at 450°C before decreasing at 550°C. SEM analysis indicated that the pyrolysis of pectin occurred via softening and melting of the subtrate followed by bubble formation. At high temperatures, surface etching followed by the appearance of crystal deposition on the char surfaces were also observed. The results are consistent with the analysis of the evolved gases. ;;‘1;22
Coke quality
requirements
for blast furnaces.
Cheng, A. Iron Steelmaker, 2001, 28, (7), 75-77. In order to maintain a certain mode of blast furnace operation it should be fed with coke having a high degree of consistency, otherwise the operation will go down and cannot be improved in the short term. Stability and performance of the blast furnace process are mostly detected by the conditions in the lower part of the furnace, where coke remains the only solid material. Tuyere coke sampling and relationships between properties of the coke below the cohesive zone (average size, size distribution, amount of fines) and furnace operation are described. $;1;23
Coke quality
requirements
for blast furnaces.
Cheng, A. Iron Steelmaker, 2001, 28, (8) 78-81. This review deals with coke degradation. Coke particle size below the cohesive zone must be large to maintain efficient and stable operation, Size particularly for low coke rate and high driving furnaces. degradation is divided into the stages from stock house to stock line and from stock line to tuyeres. Abrasion and solution loss are categorized as coke degradation mechanisms from stock line to bosh.
Solid fuels (derived
solid fuels)
Coke characteristics and coke degradation mechanisms in the tuyere and below are summarized depending on the path of the coke to the raceway or deadman.
02/01824 Part 9 Cheng, A. The effect discussed. generation show that effects of properties)
Coke quality
requirements
for blast furnaces.
Iron Sreelmaker, 2001, 28, (9) 39-40. of coke fines on blast furnace conditions and permeability is Topics include fines distribution, nature of coke fines, and mechanisms. The results of a multiple regression analysis the fine coke ratio in the deadman is susceptible to the charged coke quality (cold strength and high temperature as well as tuyere blast velocity and flame temperature.
02/01825 Coking pressure. Part II. Effect of process factors on coking pressure Kardez, A. and Winnicka, G. K&o, 2001, 46, (6), 204-208. (In Poland) Discussed is the impact of coal properties, such as the coal rank (V”“‘, R,) and selected conventional coking parameters (dilatation, plastometry) on the coking pressure. For Polish coals from Upper Silesia, evaluation of the relationship between these quality coal parameters and the coking pressure, the latter determined by the method of Nadziakiewicz-Sonntag. The significant influence of coal grain size and coal charge on the coking pressure in coke-ovens is emphasized.
02/01828 Cooling of briquets by coal fines in the manufacture of smokeless fuel Bryczkowski, A. et al. Karho, 2001, 46, (6). 2099213. (In Poland) This paper presents a modernized method for cooling of smokeless fuel briquettes with the use of powder fine coal as a cooling agent. There has also been proposed and experimental verification of the mathematical description of the briquette cooling process. The process description can be used for the design of a similar process.
02/01827 Coprocessed fuel pellets from coal, biomass and waste Cobb, J. T. and Akers, D. J. Preprinls of Symposia - American Chemical Sociefy. Division qf Fuel Chemistry, 2001, 46, (2), 715-7 16. Numerous aggregates from waste coal fines, biomass, and other wastes, such as plastics, asphalt emulsion, and sewage sludge, are developed. E-Fuel was developed and commercialized as an economical method of producing fuel pellets from a paper-making waste sludge composed of wood fibres too short for use in paper manufacture, a waste plastic used to line food container cartons, and fine-sized coal. The addition of asphalt emulsion to fine coal is the GranuFlow Process technology, and results in an agglomerated product with improved dewatering characteristics and flowability properties. Conceptual flowsheets and preliminary capital and operating costs were developed for facilities to produce fuel pellets from three formulations. Premium fuel pellets from anthracite fines and waste plastic was developed for a premium fuel market, specifically the stoker and home-heating market. From coal fines and sewage sludge the medium cost/medium quality formulation was developed for a medium grade fuel market, specifically the electricity utility steam coal market. The low cost/low quality formulation was developed using coal fines, sawdust, and asphalt emulsion for a low grade fuel market, specifically the electrical utility steam coal market.
02/01828 High carbon fly ash as a raw material and fuel source in cement manufacture Miller, F. M. et al. Proc. - Annu. In!. Pittsburgh Couf Conf, 2000, (17), 1955-1961. Two separate studies were carried out to demonstrate the use of fly ash as a component of raw kiln feed in the manufacture of portland cement. The first one includes the topics selection of fly ashes from four power plants, selection of a companion cement plant for each power plant, analysis of all of the raw materials, formulation of kiln feeds with and without the candidate fly ashes, production of cements from these kiln feeds, and testing of these cements. The results of the second study are introduced, where a similar matching of power plants and cement plants was carried out. Decisive parameters were fly ash composition, cement plant kiln feed composition, and proximity of the power plant to the cement plant. Three fly ashes were selected based on their chemical composition, C contents, and lack of volatile release at low temperature The fly ash samples and the raw materials including the target kiln feeds were analysed for their contents of SiOz, AlzOs, FezOs, CaO, MgO, alkalis and loss-on-ignition. Fuel and Energy Abstracts
July 2002
239
Economics,
business,
marketing,
policy
02/01814 Coal information for the 21st century Finkelman, R. B. er al. Proceedings - Annuul Interncrtional Pittsburgh Coul Collference, 2000, (I 7), 7-l 3. The US Geological Survey (USGS) has developed a new series of databases and products to aid the coal community in obtaining the information needed to address technological, economic, and environmental issues in the 21st century. The USGS in co-operation with the Electrical Power Research Institute and their member utilities, the Department of Energy, coal mining companies, and about 15 state agencies, are collecting and analysing approximately 1000 samples of US coal. This project will generate a broad array of reliable and accurate information on coals currently being mined and burned. The USGS in co-operation with more than 40 coal producing countries, has also initiated an international coal quality database that will contain accurate analyses of carefully collected samples from major coalproducing regions around the world. The data from these projects will be available through GEODE, a web-based interactive GIS application. These data will also be included in decision support systems that help decision-makers better assess economic and technological risks and cost effectively limit environmental degradation. 02/01815 EPRl’s view of global coal technologies for the new century Courtright, H. and Dalton, S. Proceedings - Annuul Interna/ionul Pirtshurgh Coral Conference, 2000, (I 7), 14-24. Coal use is under attack in many developed countries, and is faced with ever-tightening environmental restrictions and concerns about COz emissions. For many of the world’s countries with large percentages of the population, coal is the fuel that will be used for new power plants, Even in many developed countries, coal will continue to fuel large percentages of generation. Using coal efficiently and in an environmentally responsible manner will be a challenge for technological and 238
Fuel and Energy Abstracts
July 2002
politics of the next century. Coal use will change in the next few decades, including short-term change such as the use of more efficient ultrasupercritical boilers to longer term refining of coal to produce a range of energy and chemical outputs. A portfolio of the needed developments and demonstrations that support the long term vision, and the relative merits of these technologies are outlined. 02/01816 Strategic considerations for clean coal R&D McMullan, J. T. er al. Energy Policy, 2001, 29, (6). 441-452. While present interest in coal-fired power generation is centred on the with new natural-gas-fired power stations developing countries, predominating in the developed world, in the long term coal will return to being the fuel of choice for power generation for much of the world. To minimize the global impact of coal use it is essential, therefore, that coal technologies are developed that are efficient, clean and economically attractive. Techno-economic analyses of the options for coal presented together with a strategic overview of potential lines of development. The broad conclusions are that new coal plant will not be truly competitive with natural gas until the price of gas increases to about 3.3 euro/GJ, compared with a coal price of 1.3 euro/GJ. Present state-of-the-art pulverized coal-fired plant is close to its optimum techno-economic performance and further improvements depend on the development of cost-effective super-alloys. However, there are good opportunities to increase the efficiency of coal use to greater than 50% (LHV basis) using gasification-based power generation cycles. Unless credit is given for the much lower emissions provided by these cycles, the pulverized coal and pressurized fluidized bed combustion will remain the most economic options. 02/01817 Trends and novel technologies in the coal industry in the USA Salyaev, A. V. Ugol’ Ukrainy, 2001. (7).52-55. (In Russian) A successful development of the coal industry in the USA as the result of the high technological involvement is discussed.
Derived
solid fuels
02/01818 Apparatus and method for production of coalwater paste fuel for pressurized fluidized bed boilers Takesaki, H. e/ crl. Jpn. Kokai Tokkyo Koho JP 2001 330.238 (Cl. F23K1/02). 30 Nov 2001, Appl. 2000:150,101, 22 May 2000. 6. (In Japanese) The title apparatus comprises means for crushing raw coal from a bunker through a ball mill, means for wet grinding the coal grains with water in a 2nd ball mill to form a coal slurry, means for mixing the coal slurry and additional water and a desulphurizing agent, and means for further grinding the coal slurry and pumping it through a spray nozzle into the pressurized fluidized bed boilers. 02/01819 Bituminous coal pyrolysis tar as feedstock for carbon black production - a preliminary study Pradhan, B. K. and Eser, S. Proc. - Anmr. Inr. Pitrshurgh Coal Con/ _ 2000, (I 7), 337-365. A steadily decreasing metallurgical coke production m byproduct coke ovens in the USA, namely the strong demand for coal tar and coal-tar derived carbon precursors calls for exploring acceptable alternative processes to separate coal tar production from the parent process of coke-making in byproduct coke ovens. As a possible alternative, steam pyrolysis of bituminous coals was proposed for the production of raw coal tar, which can be further processed to produce coal tar products with desired properties. In this study, steam pyrolysis of four different coal samples (Arch, Amerikohl, Splash dam and Pocahontas #3) was carried out in a tubular reactor. Steam pyrolysis experiments were conducted at four different temperatures (500, 600, 700 and 800°C) on all the samples using a steam flow rate of 3 g/mm at a constant heating rate of lD”C/minimum The effects of heating rate and steam flow rate on the product yields were also studied for different coal samples. Changes in pyrolysis temperature, heating rate, and steam flow rate strongly affected the tar yields and composition. In general, an intermediate pyrolysis temperature (6OO”C), an intermediate steam flow rate (3 g/min), and a moderate heating rate (lO”C/min) gave the highest tar yields. Among the coal samples, Pocahontas #3 gave a much lower tar yield (3-j% wt on a dry-ash-free basis) than those of the other samples that ranged between 7 and 16 wt% on daf basis, These tar yields are much higher than that obtained in byproduct coke ovens (2-3%). The tar samples obtained were characterized by hightemperature simulated distillation using gas chromatography (HT SimDis GC) with a capillary column. The atmosphere equivalent boiling point distribution of different coal tar samples were detected by using this method. A coal tar oil sample used for carbon black production was also analysed by HT Sim-Dis GC. The atmospheric Gs oil and light
07 gas oil fractions are the major constituents (90%) of this coal tar oil. Among the tar collected from the four different coal samples, Pocahontas tar contains the least proportion of these two fractions, while Arch and Amerikohl tars have the greatest abundance of these fractions followed by the Splash Dam coal tar. Steam pyrolysis of Arch and Amerikohl coals would produce raw tars with high yields of carbon black oils. 02/01820 Briquetting method for biomass coal and its influencing factors Xu, K. et al. Hunnjing Kexue, 2001, 22, (4) 81-85. (In Chinese) A briquetting mechanism using the linkage function of biomass fibre was established for briquetting of biomass coal. The effect of different coal, briquetting pressure, biomass shape and content, and water content on the briquetting performance was studied. The results showed that the briquetting method was suitable for varied kinds coal and biomass. The briquette mechanism performance was improved with the increasing of biomass content, with a reasonable low limitation Pure biomass also could be briquetted. The briquetting of -15%. pressure which could consolidate the linkage of biomass fibre was no > 120 MPa. There would be a negative effect at too high pressure. Increasing biomass content and decreasing pressure at certain degree could offset the negative effect of water content significantly, with a permissive limitation over 10% for Datong coal. 02/01821 Characterization of chars from biomass-derived materials: pectin chars Sharma, R. K. el al. Fuel, 2001, 80, (12), 1825-1836. The effect of pyrolysis conditions on the yield and composition of char from pectin was studied. Pectin is a component of the carbohydrate fraction of biomass-derived materials. The pyrolysis was done at atmospheric pressure under oxidative and non-oxidative (inert) atmospheres and at temperatures ranging from 150 to 550°C. The volatile product was analysed by gas chromatography/mass spectrometry (GCIMS). The solid product, i.e. char, was characterized by solid-state 13C nuclear magnetic resonance (NMR) and Fouriertransform infrared (FTIR) spectroscopy. The char was also analysed for its elemental composition and surface area. The surface morphology of char was studied by scanning electron microscopy (SEM). The results were compared to those from chlorogenic acid (CA), a component of the phenolic fraction of biomass-derived materials. The behaviour of pectin was similar to that of CA. For both pectin and CA, the char yield decreased with increasing temperature before levelingoff at ca. 20% of the starting substrate in non-oxidative runs. In oxidative runs, the char yields from both substrates became negligible at 550°C. NMR analysis indicated that the aromatic character of char increased as the pyrolysis temperature increased. The oxygen functionality was progressively lost and the resonance bands corresponding to carbonyl groups mostly disappeared above 350°C. FTIR analysis also suggested the loss of hydroxyl and carbonyl groups from chars at high temperatures. The H/C and O/C ratios of chars decreased continuously with increasing temperature. The oxidative chars showed characteristics essentially similar to those of the non-oxidative chars. The surface area of char was negligible at low temperatures, but increased dramatically to a maximum of 70 m2 g -’ at 450°C before decreasing at 550°C. SEM analysis indicated that the pyrolysis of pectin occurred via softening and melting of the subtrate followed by bubble formation. At high temperatures, surface etching followed by the appearance of crystal deposition on the char surfaces were also observed. The results are consistent with the analysis of the evolved gases. ;;‘1;22
Coke quality
requirements
for blast furnaces.
Cheng, A. Iron Steelmaker, 2001, 28, (7), 75-77. In order to maintain a certain mode of blast furnace operation it should be fed with coke having a high degree of consistency, otherwise the operation will go down and cannot be improved in the short term. Stability and performance of the blast furnace process are mostly detected by the conditions in the lower part of the furnace, where coke remains the only solid material. Tuyere coke sampling and relationships between properties of the coke below the cohesive zone (average size, size distribution, amount of fines) and furnace operation are described. $;1;23
Coke quality
requirements
for blast furnaces.
Cheng, A. Iron Steelmaker, 2001, 28, (8) 78-81. This review deals with coke degradation. Coke particle size below the cohesive zone must be large to maintain efficient and stable operation, Size particularly for low coke rate and high driving furnaces. degradation is divided into the stages from stock house to stock line and from stock line to tuyeres. Abrasion and solution loss are categorized as coke degradation mechanisms from stock line to bosh.
Solid fuels (derived
solid fuels)
Coke characteristics and coke degradation mechanisms in the tuyere and below are summarized depending on the path of the coke to the raceway or deadman.
02/01824 Part 9 Cheng, A. The effect discussed. generation show that effects of properties)
Coke quality
requirements
for blast furnaces.
Iron Sreelmaker, 2001, 28, (9) 39-40. of coke fines on blast furnace conditions and permeability is Topics include fines distribution, nature of coke fines, and mechanisms. The results of a multiple regression analysis the fine coke ratio in the deadman is susceptible to the charged coke quality (cold strength and high temperature as well as tuyere blast velocity and flame temperature.
02/01825 Coking pressure. Part II. Effect of process factors on coking pressure Kardez, A. and Winnicka, G. K&o, 2001, 46, (6), 204-208. (In Poland) Discussed is the impact of coal properties, such as the coal rank (V”“‘, R,) and selected conventional coking parameters (dilatation, plastometry) on the coking pressure. For Polish coals from Upper Silesia, evaluation of the relationship between these quality coal parameters and the coking pressure, the latter determined by the method of Nadziakiewicz-Sonntag. The significant influence of coal grain size and coal charge on the coking pressure in coke-ovens is emphasized.
02/01828 Cooling of briquets by coal fines in the manufacture of smokeless fuel Bryczkowski, A. et al. Karho, 2001, 46, (6). 2099213. (In Poland) This paper presents a modernized method for cooling of smokeless fuel briquettes with the use of powder fine coal as a cooling agent. There has also been proposed and experimental verification of the mathematical description of the briquette cooling process. The process description can be used for the design of a similar process.
02/01827 Coprocessed fuel pellets from coal, biomass and waste Cobb, J. T. and Akers, D. J. Preprinls of Symposia - American Chemical Sociefy. Division qf Fuel Chemistry, 2001, 46, (2), 715-7 16. Numerous aggregates from waste coal fines, biomass, and other wastes, such as plastics, asphalt emulsion, and sewage sludge, are developed. E-Fuel was developed and commercialized as an economical method of producing fuel pellets from a paper-making waste sludge composed of wood fibres too short for use in paper manufacture, a waste plastic used to line food container cartons, and fine-sized coal. The addition of asphalt emulsion to fine coal is the GranuFlow Process technology, and results in an agglomerated product with improved dewatering characteristics and flowability properties. Conceptual flowsheets and preliminary capital and operating costs were developed for facilities to produce fuel pellets from three formulations. Premium fuel pellets from anthracite fines and waste plastic was developed for a premium fuel market, specifically the stoker and home-heating market. From coal fines and sewage sludge the medium cost/medium quality formulation was developed for a medium grade fuel market, specifically the electricity utility steam coal market. The low cost/low quality formulation was developed using coal fines, sawdust, and asphalt emulsion for a low grade fuel market, specifically the electrical utility steam coal market.
02/01828 High carbon fly ash as a raw material and fuel source in cement manufacture Miller, F. M. et al. Proc. - Annu. In!. Pittsburgh Couf Conf, 2000, (17), 1955-1961. Two separate studies were carried out to demonstrate the use of fly ash as a component of raw kiln feed in the manufacture of portland cement. The first one includes the topics selection of fly ashes from four power plants, selection of a companion cement plant for each power plant, analysis of all of the raw materials, formulation of kiln feeds with and without the candidate fly ashes, production of cements from these kiln feeds, and testing of these cements. The results of the second study are introduced, where a similar matching of power plants and cement plants was carried out. Decisive parameters were fly ash composition, cement plant kiln feed composition, and proximity of the power plant to the cement plant. Three fly ashes were selected based on their chemical composition, C contents, and lack of volatile release at low temperature The fly ash samples and the raw materials including the target kiln feeds were analysed for their contents of SiOz, AlzOs, FezOs, CaO, MgO, alkalis and loss-on-ignition. Fuel and Energy Abstracts
July 2002
239