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Coke quality requirements for blast furnaces. Part 9
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
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