This work examines the fundamental flow behaviour of granular materials under conditions relevant to blast furnace. Such a study may have some impact on the development of new technology to improve performance of blast furnace operation. The blast furnace operation involves rich granular dynamics phenomena which currently attract a strong interest from wide scientific and engineering community. In this work, percolation phenomenon is analyzed extensively. Percolation phenomenon is one of the most significant factors which cause particle segregation and mixing. In blast furnace when sinter and coke of different size and density are charged, percolation phenomenon occurs. In this work percolation properties like percolation velocity, residence time distribution and radial dispersion are checked for different material properties of percolating particles. It was found that percolation behaviour is related to many factors. Percolation properties of a single particle and also for batches of percolating particle were examined. The effect of external forces on percolation properties is also checked. DEM simulation method was found to be suitable for analysis of percolation flow behaviour of different types of particles. It was also found that the change of packed bed conditions has a great impact on particle percolation and segregation behaviour. In a packed bed, vibration and liquid of different properties were introduced. Particle dynamics in descending packed bed condition was checked. The effect of vibration and descending velocity was measured for percolation behaviour. Both vibration frequency and amplitude are important factors for particle flow in such a packed bed. Descending velocity of packed particles combined with vibration was found to have a pronounced impact on percolation behaviour. Liquid properties like viscosity and density affect particle dynamics significantly. Particle segregation in a pile was investigated as an extension of the percolation study. The effects of diameter ratio of binary feed, initial mixing ratio, feed rate in case of central feeding on conical pile were investigated. It was found that all of those parameters affect particle flow and segregation. Flowing layer over static pile was simulated and velocity profile and mixing ratio in different layers were observed. 3-D Screening Layer model was validated by DEM and experiment. In case of multipoint feed system, a conical pile which is similar to the deadman of a blast furnace was generated and the flowing layer characteristics over this static pile was also analysed.

No description available.

<p> An experimental investigation has been conducted into the reduction of iron oxides under blast furnace conditions. The necessary equipment has been designed, constructed and tested, and a program of study on two types of prereduced ore materials has been completed.</p> / Thesis / Master of Science (MSc)

Thesis: Sc. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 1980 / Vita. / Includes bibliographical references. / by Balkishan Agrawal. / Sc. D. / Sc. D. Massachusetts Institute of Technology, Department of Materials Science and Engineering

<p>The main objectives of this study were to investigate (i) anovel wetland treatment technology and (ii) selected bed filtermedia for the removal of contaminants from landfill leachate. Areview of the literature concerning experiences of the use ofconstructed wetlands (CW) for the removal of nitrogen fromlandfill leachate, showed that at least three groups oftreatment systems are in practice: sub-surface flow wetlands,hybrid systems (a combination of vertical and horizontal flowwetlands) and, compact constructed wetland (CCW). Most of thesetypeswere generally effective in reducing nitrogen (N,<i>e.g.</i>NH₄-N, dominant N species in leachate) down toeffluent concentrations of about 10 mg L^-1. Unfortunately, very little evidence ofresponsible mechanisms for the removal of N was presented,although some data indicated denitrification. The treatmentperformance of a compact constructed wetland (CCW) applied atthe Tveta Landfill, Södertälje, Sweden, wasevaluated. Chemically purified leachate and untreated leachatewere applied in periods of 7 day submergence and 7 day drainageto different sections of the CCW. The removal efficiency variedbetween 40 and 82%, and a mass removal rate of up to 5.1 g m²d^-1was achieved. The chemical pre-treatment had adecisive role for the highest removal efficiencies obtained andit was unclear whether that treatment enhanced the efficiencybecause of lower toxicity and/or content of fewer competingcations. The possible combination of bed filter media and CCWas an ecotechnological treatment method for landfill leachatewas investigated by bench-scale laboratory column experiments.Reactive filter media (sorbents) was selected from their knownor suggested capacities for removal of heavy metals, nitrogenand phosphorus. Quartz sand or natural sand from an esker wasused as reference medium. Peat was used as an additionalcomponent in mixtures with the reactive media Polonite^®(product from the bedrock opoka) and blastfurnace slag (BFS). A small column study also involved zeolite.Phosphorus was efficiently removed by Polonite^®and NH₄-N to some extent. Concerning metal removal, thebest performance was found as well for Polonite^®, especially for Mn, Fe, Zn and Cu. The BFSshowed good removal efficiency for Cu, Ni and Mo. The removalof different elements was suggested to be a combination ofseveral factors,<i>e.g.</i>precipitation, ion exchange and adsorption. Priorto full-scale application of reactive filters at a landfillsite, matrix selection, filter design and operationalprocedures must be developed.</p><p><b>Keywords:</b>Blast furnace slag; Compact constructedwetland; Metals; Nitrogen; Polonite; Sorbents</p>

Os cimentos de escória apresentam boas possibilidades de mercado, especialmente em aplicações em que o cimento Portland não possa ser utilizado ou onde o seu uso provoque uma elevação dos custos. A confecção de matrizes para fibras sensíveis aos álcalis e a produção de cimentos com baixo calor de hidratação são exemplos. Neste trabalho, a escória foi ativada com silicato de sódio e cal hidratada. O ativador foi formulado de maneira a proporcionar teores de Na2O de 2,5% e 5%, SiO2 de 0% a 14,8% e Ca(OH)2 de 0%, 2,5% e 5%. O aumento dos teores de Na2O e de SiO2, dentro de determinados limites, propicia um notável crescimento da resistência à compressão. Este crescimento da resistência está associado a uma diminuição da porosidade, para um mesmo fator/água aglomerante. Certamente a diminuição da porosidade é devida a um menor grau de organização cristalina dos produtos hidratados, decorrente do aumento da velocidade de precipitação de hidratados e de gel de N-C-S-H. A adição de Ca(OH)2 diminui a velocidade de perda da trabalhabilidade. Os cimentos de escória ativada com silicatos de sódio podem apresentar resistência à compressão de até 100 MPa, superior à dos cimentos Portland, com calor de hidratação da mesma ordem de grandeza. A velocidade de carbonatação destes cimentos é equivalente a dos cimentos Portland de mesma resistência. No entanto, estes cimentos apresentam maior retração hidráulica. / Binders based on ground granulated blast furnace slag (BFS) are suitable for the building industry, mainly if the use of Portland cement is expensive or may cause problems, such as: alkali sensitive fibre-reinforced cement and concretes and low heat-hydration concretes. BFS is activated by sodium silicates and hydrated lime. The compound\'s proportions are: Na2O - 2.5 and 5.0%; SiO2 from 0 to 14.8%; CaOH2 - 0, 2.5 and 5%. The increase of Na2O and SiO2 amounts allows a considerable improvement of binder strength, with values up to 100 MPa. This increase of the strength is related to the decrease of the porosity for a constant water-binder ratio. The porosity is affected certainly by the reduction of the degree of cristalynity of the hydrated compounds, due to the increase of the speed of precipitation of the hydrates or the N-C-S-H gel. It is possible to obtain BFS binders stronger than the Portland cement, with similar hydration heat. The carbonation rate of these new binders is equivalent to those of Portland cement specimens with similar strength. However these BFS binders have higher drying shrinkage.

Os cimentos de escória apresentam boas possibilidades de mercado, especialmente em aplicações em que o cimento Portland não possa ser utilizado ou onde o seu uso provoque uma elevação dos custos. A confecção de matrizes para fibras sensíveis aos álcalis e a produção de cimentos com baixo calor de hidratação são exemplos. Neste trabalho, a escória foi ativada com silicato de sódio e cal hidratada. O ativador foi formulado de maneira a proporcionar teores de Na2O de 2,5% e 5%, SiO2 de 0% a 14,8% e Ca(OH)2 de 0%, 2,5% e 5%. O aumento dos teores de Na2O e de SiO2, dentro de determinados limites, propicia um notável crescimento da resistência à compressão. Este crescimento da resistência está associado a uma diminuição da porosidade, para um mesmo fator/água aglomerante. Certamente a diminuição da porosidade é devida a um menor grau de organização cristalina dos produtos hidratados, decorrente do aumento da velocidade de precipitação de hidratados e de gel de N-C-S-H. A adição de Ca(OH)2 diminui a velocidade de perda da trabalhabilidade. Os cimentos de escória ativada com silicatos de sódio podem apresentar resistência à compressão de até 100 MPa, superior à dos cimentos Portland, com calor de hidratação da mesma ordem de grandeza. A velocidade de carbonatação destes cimentos é equivalente a dos cimentos Portland de mesma resistência. No entanto, estes cimentos apresentam maior retração hidráulica. / Binders based on ground granulated blast furnace slag (BFS) are suitable for the building industry, mainly if the use of Portland cement is expensive or may cause problems, such as: alkali sensitive fibre-reinforced cement and concretes and low heat-hydration concretes. BFS is activated by sodium silicates and hydrated lime. The compound\'s proportions are: Na2O - 2.5 and 5.0%; SiO2 from 0 to 14.8%; CaOH2 - 0, 2.5 and 5%. The increase of Na2O and SiO2 amounts allows a considerable improvement of binder strength, with values up to 100 MPa. This increase of the strength is related to the decrease of the porosity for a constant water-binder ratio. The porosity is affected certainly by the reduction of the degree of cristalynity of the hydrated compounds, due to the increase of the speed of precipitation of the hydrates or the N-C-S-H gel. It is possible to obtain BFS binders stronger than the Portland cement, with similar hydration heat. The carbonation rate of these new binders is equivalent to those of Portland cement specimens with similar strength. However these BFS binders have higher drying shrinkage.

Resumo: Esta dissertação analisou a viabilidade técnica de gaseificação de lama de alto de alto forno da ArcelorMittal Tubarão para produção de gás visando uma utilização interna. A gaseificação foi conduzida através de simulação em modelo de equilíbrio químico TCW - Termochemical Information and Equlibrium Calculation. Foram simuladas 3 misturas para gaseificação: a) 100% carvão metalúrgico de alto volátil (base das misturas), b) de lama de alto forno com 85% de carvão metalúrgico alto volátil e c) de lama de alto forno com 75% de carvão metalúrgico alto volátil. Os dois parâmetros principais que definiram a viabilidade técnica de gaseificação de lama de alto forno foram poder calorífico inferior - PCI e faixas de trabalho temperaturas no reator. O PCI do gás foi calculado a partir das frações molares de H2 e CO contidas no gás obtidos nas misturas simuladas / Abstract: This dissertation analyzed the technical viability of blast furnace slurry gasification with the objective of using the obtained gas at ArcelorMittal Tubarão. The process was simulated using an equilibrium program, the TCW - Termochemical Information and Equilibrium Calculation. Three mixtures were considered for gasification: a) 100% high volatile metallurgical coal (the base of the mixtures), b) 15% slurry and 85% coal, and c) 25% slurry and 25% coal. The two main parameters that defined the technical viability of the blast furnace slurry were the mixture Low Heat Value (LHV) and the temperature ranges for work in the gasification reactor. The LHV was calculated from the molar fractions of H2 and CO in the gas obtained in the simulation / Orientador: João Andrade de Carvalho Junior / Coorientador: Sergio Leite Lopes / Banca: Luiz Roberto Carrocci / Mestre

The blast furnace is still the dominant form of iron production, but over the years, direct reduction methods have increased due to a number of reasons. Overall, iron production methods have optimal requirements with respect to the feed materials especially iron ore. In this study, tests were carried out on Muko iron ore from Uganda to analyse its suitability to meet the feed requirements of today's dominant iron production methods. More specifically, the Tumbler, Abrasion, and Shatter Indices of the ore were determined. In addition, porosity, thermoanalysis, and reducibility tests were performed. Overall, the Muko ore was found to have good mechanical properties exemplified with tumble and shatter index data &gt;89.0 wt% and &lt;2.5 wt%, respectively. Furthermore, its reducibility at 0.87%/min is within the acceptable range as a natural material feed for blast furnace and direct reduction furnaces. Also, the energy requirement for heating the ore to 1100°C was found to be higher in the samples containing a wider size range of irregular grains and the largest contaminations. In summary, it is concluded that the Muko iron ore has good physical and metallurgical properties to serve as a natural material for the blast furnace and direct reduction furnaces. / <p>QC 20130531</p> / Sustainable Technology Development in the Lake Victoria Region

Thanks to the booming of China and eastern Europe demanding, the world steel annual production soaring from 0.75 billion tons in 1990 to 1.239 billion tons in 2006, the percentage of top 10 steel company is 28.43% of the world production and it is a history record. It looks like raw material industrial like steel makers are shinning. Nevertheless, due to merge of the steel industry and final product customer of local market were shifting to the China market, threaten are increasing. Therefore, to find out how China Steel gains more competition through her resource integration becomes main reason of this research. In Blast Furnace steel making, the co-relationship between upstream and downstream is highly cohesive, China Steel has started to set up her Process computer system since 1979. The main function of the Process computer is to receive production order from ERP system and download the receipt to the low level controller through its built in model; During production, the Process computer also track the material from semi-product to the final product, A Quality evaluation system in every Process computer system also helping the production supervisor to make sure the quality of the outlet. To leverage the thirty years Process computer know-how becomes main search of this essay. Through survey of Dragon steel¡BChung-Hung Info Steel and Inform-Champ corporation to study their current status of the system¡Borganization and requirement, list all the demanding and possible solution as an information base, then use RBV to analysis these demanding. This research will based on the process computer know-how center of the CSC Process control computer shop to establish a new process to contribute the following ¡§Rent¡¨ in CSC group: (1). To readjust the data flow of CSC Process control computer shop based on the competition acknowledge survey of all the team members in this shop. (2) To support Chung-Hung Steel for his revamping and new process control computer system. (3) To support Dragon steel to establish his own maintenance system and to handle the new project of the Dragon Steel to minimize the project organization manpower. (4) To establish a common platform of spare parts and an integrated purchasing system to minimize the stock of spare parts and to meet the economic scale on purchasing. (5) To establish a model research center in China steel as a CSC Group model ware. (6) To assist ICSC to set-up his total solution capability of process computer technology