The Experts below are selected from a list of 6933 Experts worldwide ranked by ideXlab platform
Jun-ichiro Yagi - One of the best experts on this subject based on the ideXlab platform.
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multi dimensional transient mathematical simulator of Blast Furnace Process based on multi fluid and kinetic theories
Computers & Chemical Engineering, 2005Co-Authors: Hiroshi Nogami, Mansheng Chu, Jun-ichiro YagiAbstract:The ironmaking Blast Furnace is regarded as one of the biggest and most complex industrial reactors, because it includes various materials like gas, lump granular materials, liquids and powders and more than 30 major reactions and phase changes in a single reaction vessel. The mathematical simulator of this Process developed in this study used the multi-fluid treatment as its framework, since the motions of these materials were governed by different flow mechanisms. The rates of the interactions among the phases and the chemical reactions were evaluated based on kinetic theories. The model successfully reproduced the fields of velocity, temperature and reaction in the Furnace and its validity was confirmed. The simulator was also applied to a novel operation, namely the top gas recycling combined with the carbon-composite iron-ore charging and the waste plastics injection, and the advantages in Furnace efficiency and environmental load were quantitatively indicated.
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numerical investigation of simultaneous injection of pulverized coal and natural gas with oxygen enrichment to the Blast Furnace
Isij International, 2002Co-Authors: José Adilson De Castro, Hiroshi Nogami, Jun-ichiro YagiAbstract:The multiple injection of carbonaceous materials and oxygen enrichment in the Blast Furnace has received especial attention in the recent years due to its possibility of considerably decrease in coke rate and increase of the productivity. This paper introduces a modeling of the co-injection of pulverized coal and natural gas into the Blast Furnace through the tuyere. This model treats the Blast Furnace as a multi-phase reactor and five phases are treated simultaneously: gas, lump solids (iron ore, sinter, pellets and coke), pig iron, molten slag and pulverized coal. Conservation equations for mass, momentum, energy and chemical species are solved simultaneously based on the finite volume method. Firstly pulverized coal is simulated and afterwards only natural gas is investigated and compared with the all coke operation. Finally, the combined practice is suggested in order to improve the actual Blast Furnace operation. The simulation results have contributed to better understanding the Blast Furnace phenomena with multiple injectants, and supported new improvements in the Furnace operation. The results obtained in this investigation have shown the possibility of considerable advances in the actual Blast Furnace operation such as increase in productivity, lower silicon content in hot metal and decrease of the coke and slag rates. In addition, the total amount of the greenhouses in the off gas is decreased, which contributes to make the Blast Furnace Process cleaner.
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three dimensional multiphase mathematical modeling of the Blast Furnace based on the multifluid model
Isij International, 2002Co-Authors: José Adilson De Castro, Hiroshi Nogami, Jun-ichiro YagiAbstract:The Blast Furnace Process is a multi-phase chemical reactor whose main purpose is to reduce iron oxides producing hot metal. In the actual Blast Furnace operation several phases simultaneously interact with one another exchanging momentum, mass and energy. In this paper a three-dimensional multiphase mathematical model of the Blast Furnace is presented. This model treats the Blast Furnace Process as a multiphase reactor in which all phases behave like fluids. Five phases are treated by this model, namely, gas, lump solids (iron ore, sinter, pellets and coke), pig iron, molten slag and pulverized coal. Conservation equations for mass, momentum, energy and chemical species for all phases are solved based on the finite volume method. In the discretized momentum equations, the covariant velocity projections are used, which is expected to give the best coupling between the velocity and pressure fields and improve the convergence of the calculations. This is a new feature of the present model regarding to the numerical procedures applied to the Blast Furnace modeling, which emphasizes its originality. In addition, gas and solid phases are treated as continuous phases possessing a pressure field and the SIMPLE algorithm is applied to extract the pressure field and ensure mass conservation. Hot metal, slag and pulverized coal are treated as discontinuous phases consisting of unconnected droplets. For such phases, momentum conservation is used to calculate the fields of velocity while the continuity equations are used to calculate the phase volume fractions. This model was applied to predict the three-dimensional Blast Furnace operation and predicted temperature distributions and operational parameters like productivity, coke rate and slag rate presented close agreement with the actual measured ones in the Blast Furnace Process.
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transient mathematical model of Blast Furnace based on multi fluid concept with application to high pci operation
Isij International, 2000Co-Authors: José Adilson De Castro, Hiroshi Nogami, Jun-ichiro YagiAbstract:The ironmaking Blast Furnace is a counter current chemical reactor whose main purpose is to produce hot metal (pig iron) from iron oxides. In the Furnace, five phases: gas, lump solids (iron ore, sinter, pellets and coke), liquids (pig iron and molten slag) and powders (tuyere injectants: pulverized coal, coke fines or dust from the lump coke) interact with one another. In order to evaluate productivity, energy efficiency and transient phenomena occurring in the Blast Furnace, a comprehensive two-dimensional transient mathematical model has been developed. The model was composed of conservation equations of mass, momentum, chemical species and thermal energy for all phases mentioned above. This model includes phase transformations and chemical reactions such as melting of pig iron and slag components, moisture evaporation, reduction of iron oxides, solution loss, coke and pulverized coal combustion, silica reduction and gas phase reactions. With this model, the transient behavior of the Blast Furnace Process has been successfully predicted for different injection rates of pulverized coal.
Mansheng Chu - One of the best experts on this subject based on the ideXlab platform.
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reduction behavior of vanadium titanium magnetite carbon composite hot briquette in Blast Furnace Process
Powder Technology, 2019Co-Authors: Wei Zhao, Mansheng Chu, Hongtao Wang, Zhenggen Liu, Jue Tang, Ziwei YingAbstract:Abstract The reduction behavior of a new type of Blast Furnace burden named vanadium‑titanium magnetite carbon composite hot briquette (hereinafter abbreviated as VTM-CCB), including fraction of reaction (f), reduction shrinking, crushing strength after reduction, phase transformation of valuable elements, and softening-melting-dripping behavior, were investigated with simulating Blast Furnace conditions in laboratory in this article. The reduction Process of VTM-CCB could be divided into four stages. The devolatilization of the coal and the reduction of magnetite to wustite mainly occur successively in the first two stages. In the third stage, the reduction rate is much higher than that in the second stage due to the high carbon gasification rate. The reduction of Ti-bearing iron oxides occurs in the final stage. The shrinking of VTM-CCB samples is caused by the removal of carbon and oxygen and the suppression of the growth of iron whiskers during the reduction of wustite to metallic iron. The crushing strength of VTM-CCB after reduction is found to decrease from 1800 N to 600 N correspondingly with increasing temperature from 600 °C to 1100 °C. The loss of the crushing strength correlates to the pyrolysis of the coal, the carbon gasification, and the reduction of iron oxides. The phase transformation of valuable elements during reduction could be described as follows: Fe3O4 → FeO → Fe; Fe2.75Ti0.25O4 → Fe2.5Ti0.5O4 → (Fe2TiO4) → FeTiO3 → (FeTi2O5) → TiO2. The softening-melting-dripping behavior and permeability of mixed burden is improved obviously with charging a certain amount of VTM-CCB. However, the precipitation of Ti(C,N) would deteriorate the dripping behavior of packed bed when VTM-CCB charging ratio exceeds 20%.
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mathematical simulation on Blast Furnace operation of coke oven gas injection in combination with top gas recycling
Steel Research International, 2016Co-Authors: Hongtao Wang, Mansheng Chu, Wei Zhao, Zhenggen Liu, Tonglai Guo, Cong Feng, Jue TangAbstract:In order to further improve Blast Furnace operational performance, reduce carbon emission, and increase gas utilization efficiency under only coke oven gas (COG) injection, a Blast Furnace Process of COG injection together with top gas recycling through tuyere injection (TI) and/or shaft injection (SI) had been mathematically simulated in this study. The effects of this new Process on in-Furnace status, operation parameters, and energy utilization are investigated by means of multi-fluid Blast Furnace model. The results show that compared with only COG injection, solid temperature slightly decreases and cohesive zone tends to move downward and narrow under simultaneous COG injection and top gas recycling. Meanwhile, the reduction degree of iron-bearing burdens evidently increases before entering cohesive zone due to more involvement of hydrogen into indirect reduction. Furthermore, the operation of COG injection combined with top gas recycling can achieve Blast Furnace ironmaking with low carbon emission, low energy consumption, and high efficiency. For example, hot metal productivity and corrected CO utilization efficiency under COG injection and TI increase by 13.87 and 6.95%, respectively. Additionally, carbon emission ratio and energy consumption decrease by 39.57 and 15.78%, respectively. Taking into account in-Furnace status, operational parameters, and energy consumption, the operation of COG injection and top gas recycling through TI is recommended as more feasible choice for the possible practical application.
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multi dimensional transient mathematical simulator of Blast Furnace Process based on multi fluid and kinetic theories
Computers & Chemical Engineering, 2005Co-Authors: Hiroshi Nogami, Mansheng Chu, Jun-ichiro YagiAbstract:The ironmaking Blast Furnace is regarded as one of the biggest and most complex industrial reactors, because it includes various materials like gas, lump granular materials, liquids and powders and more than 30 major reactions and phase changes in a single reaction vessel. The mathematical simulator of this Process developed in this study used the multi-fluid treatment as its framework, since the motions of these materials were governed by different flow mechanisms. The rates of the interactions among the phases and the chemical reactions were evaluated based on kinetic theories. The model successfully reproduced the fields of velocity, temperature and reaction in the Furnace and its validity was confirmed. The simulator was also applied to a novel operation, namely the top gas recycling combined with the carbon-composite iron-ore charging and the waste plastics injection, and the advantages in Furnace efficiency and environmental load were quantitatively indicated.
Miika Sihvonen - One of the best experts on this subject based on the ideXlab platform.
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oxygen Blast Furnace with co2 capture and storage at an integrated steel mill part ii economic feasibility in comparison with conventional Blast Furnace highlighting sensitivities
International Journal of Greenhouse Gas Control, 2015Co-Authors: Eemeli Tsupari, Janne Karki, Antti Arasto, Jarmo Lilja, Kimmo Kinnunen, Miika SihvonenAbstract:Abstract This article is part II of the series of two papers regarding the application of oxygen Blast Furnace (OBF) in Ruukki Metals Ltd.’s existing steel mill, located in city of Raahe, Finland. The economic assessment presented in this paper is based on the technical modelling presented in part I of the study. OBF with CCS would lead to large reductions in CO 2 emissions but also OBF without CCS would decrease emissions significantly due to decreased coke consumption. From economic point of view, other important consequences of OBF Process are increased LPG or LNG (liquefied petroleum gas or liquefied natural gas) consumption, decreased electricity production (increased purchase from markets), required investments and CO 2 transportation and storage costs. As CCS Processes typically, especially application of OBF is a trade-off between decreased electricity production and decreased emissions. Therefore a correlation between CO 2 price development and electricity price development is of interest. In this paper, several sensitivity analyses are presented with different prices for CO 2 , electricity and other parameters. The results present the sensitivity of different options in terms of economic feasibility for large CO 2 reductions in the integrated steel mill based on Blast Furnace Process.
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oxygen Blast Furnace with co2 capture and storage at an integrated steel mill part i technical concept analysis
International Journal of Greenhouse Gas Control, 2014Co-Authors: Antti Arasto, Eemeli Tsupari, Janne Karki, Jarmo Lilja, Miika SihvonenAbstract:Abstract In this study application of OBF with and without CCS to an integrated steel mill is investigated. The study is based on the real, Ruukki Metals Ltd.’s existing steel mill, located in the city of Raahe, Finland. Implications of application of OBF to energy and mass balances at the site are studied. Based on the technical evaluation, costs and feasibility for carbon capture are estimated. The energy and mass balance basis is presented in this first part of the series of two papers. Costs, feasibility and sensitivity analysis are assessed in the second part of the series (Tsupari et al. 2014. Int. J. Greenhouse Gas Control). The impact of applying OBF at an integrated steel mill is evaluated based on a consequential assessment following the methodology of Arasto et al. (2013). Int. J. Greenhouse Gas Control 16 (August) pp. 271–277 concentrating only on the parts of the steelmaking Processes affected by the deployment of OBF and CO 2 capture. The technical Processes, CO 2 capture and the steelmaking Processes affected were modelled using Aspen Plus Process modelling software and the results were used to estimate the CO 2 emission reduction potential with OBF technology at an integrated steel mill. The results show that the CO 2 emission from an iron and steel mill can be significantly reduced by application of an oxygen Blast Furnace and CCS. By applying only the Blast Furnace Process, the emissions can already be reduced by 1.2 Mt/a without storing the separated CO 2 . If captured CO 2 is also purified and stored permanently, the emission can be further reduced by an additional 1.4 Mt/a. This is a significant reduction considering that the production of the mill stays the same as in the reference case. In addition to carbon footprint of the production, application of oxygen Blast Furnace also has significant impact on coke consumption and energy balance on the site.
Hiroshi Nogami - One of the best experts on this subject based on the ideXlab platform.
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multi dimensional transient mathematical simulator of Blast Furnace Process based on multi fluid and kinetic theories
Computers & Chemical Engineering, 2005Co-Authors: Hiroshi Nogami, Mansheng Chu, Jun-ichiro YagiAbstract:The ironmaking Blast Furnace is regarded as one of the biggest and most complex industrial reactors, because it includes various materials like gas, lump granular materials, liquids and powders and more than 30 major reactions and phase changes in a single reaction vessel. The mathematical simulator of this Process developed in this study used the multi-fluid treatment as its framework, since the motions of these materials were governed by different flow mechanisms. The rates of the interactions among the phases and the chemical reactions were evaluated based on kinetic theories. The model successfully reproduced the fields of velocity, temperature and reaction in the Furnace and its validity was confirmed. The simulator was also applied to a novel operation, namely the top gas recycling combined with the carbon-composite iron-ore charging and the waste plastics injection, and the advantages in Furnace efficiency and environmental load were quantitatively indicated.
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numerical investigation of simultaneous injection of pulverized coal and natural gas with oxygen enrichment to the Blast Furnace
Isij International, 2002Co-Authors: José Adilson De Castro, Hiroshi Nogami, Jun-ichiro YagiAbstract:The multiple injection of carbonaceous materials and oxygen enrichment in the Blast Furnace has received especial attention in the recent years due to its possibility of considerably decrease in coke rate and increase of the productivity. This paper introduces a modeling of the co-injection of pulverized coal and natural gas into the Blast Furnace through the tuyere. This model treats the Blast Furnace as a multi-phase reactor and five phases are treated simultaneously: gas, lump solids (iron ore, sinter, pellets and coke), pig iron, molten slag and pulverized coal. Conservation equations for mass, momentum, energy and chemical species are solved simultaneously based on the finite volume method. Firstly pulverized coal is simulated and afterwards only natural gas is investigated and compared with the all coke operation. Finally, the combined practice is suggested in order to improve the actual Blast Furnace operation. The simulation results have contributed to better understanding the Blast Furnace phenomena with multiple injectants, and supported new improvements in the Furnace operation. The results obtained in this investigation have shown the possibility of considerable advances in the actual Blast Furnace operation such as increase in productivity, lower silicon content in hot metal and decrease of the coke and slag rates. In addition, the total amount of the greenhouses in the off gas is decreased, which contributes to make the Blast Furnace Process cleaner.
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three dimensional multiphase mathematical modeling of the Blast Furnace based on the multifluid model
Isij International, 2002Co-Authors: José Adilson De Castro, Hiroshi Nogami, Jun-ichiro YagiAbstract:The Blast Furnace Process is a multi-phase chemical reactor whose main purpose is to reduce iron oxides producing hot metal. In the actual Blast Furnace operation several phases simultaneously interact with one another exchanging momentum, mass and energy. In this paper a three-dimensional multiphase mathematical model of the Blast Furnace is presented. This model treats the Blast Furnace Process as a multiphase reactor in which all phases behave like fluids. Five phases are treated by this model, namely, gas, lump solids (iron ore, sinter, pellets and coke), pig iron, molten slag and pulverized coal. Conservation equations for mass, momentum, energy and chemical species for all phases are solved based on the finite volume method. In the discretized momentum equations, the covariant velocity projections are used, which is expected to give the best coupling between the velocity and pressure fields and improve the convergence of the calculations. This is a new feature of the present model regarding to the numerical procedures applied to the Blast Furnace modeling, which emphasizes its originality. In addition, gas and solid phases are treated as continuous phases possessing a pressure field and the SIMPLE algorithm is applied to extract the pressure field and ensure mass conservation. Hot metal, slag and pulverized coal are treated as discontinuous phases consisting of unconnected droplets. For such phases, momentum conservation is used to calculate the fields of velocity while the continuity equations are used to calculate the phase volume fractions. This model was applied to predict the three-dimensional Blast Furnace operation and predicted temperature distributions and operational parameters like productivity, coke rate and slag rate presented close agreement with the actual measured ones in the Blast Furnace Process.
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transient mathematical model of Blast Furnace based on multi fluid concept with application to high pci operation
Isij International, 2000Co-Authors: José Adilson De Castro, Hiroshi Nogami, Jun-ichiro YagiAbstract:The ironmaking Blast Furnace is a counter current chemical reactor whose main purpose is to produce hot metal (pig iron) from iron oxides. In the Furnace, five phases: gas, lump solids (iron ore, sinter, pellets and coke), liquids (pig iron and molten slag) and powders (tuyere injectants: pulverized coal, coke fines or dust from the lump coke) interact with one another. In order to evaluate productivity, energy efficiency and transient phenomena occurring in the Blast Furnace, a comprehensive two-dimensional transient mathematical model has been developed. The model was composed of conservation equations of mass, momentum, chemical species and thermal energy for all phases mentioned above. This model includes phase transformations and chemical reactions such as melting of pig iron and slag components, moisture evaporation, reduction of iron oxides, solution loss, coke and pulverized coal combustion, silica reduction and gas phase reactions. With this model, the transient behavior of the Blast Furnace Process has been successfully predicted for different injection rates of pulverized coal.
Wei Zhao - One of the best experts on this subject based on the ideXlab platform.
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reduction behavior of vanadium titanium magnetite carbon composite hot briquette in Blast Furnace Process
Powder Technology, 2019Co-Authors: Wei Zhao, Mansheng Chu, Hongtao Wang, Zhenggen Liu, Jue Tang, Ziwei YingAbstract:Abstract The reduction behavior of a new type of Blast Furnace burden named vanadium‑titanium magnetite carbon composite hot briquette (hereinafter abbreviated as VTM-CCB), including fraction of reaction (f), reduction shrinking, crushing strength after reduction, phase transformation of valuable elements, and softening-melting-dripping behavior, were investigated with simulating Blast Furnace conditions in laboratory in this article. The reduction Process of VTM-CCB could be divided into four stages. The devolatilization of the coal and the reduction of magnetite to wustite mainly occur successively in the first two stages. In the third stage, the reduction rate is much higher than that in the second stage due to the high carbon gasification rate. The reduction of Ti-bearing iron oxides occurs in the final stage. The shrinking of VTM-CCB samples is caused by the removal of carbon and oxygen and the suppression of the growth of iron whiskers during the reduction of wustite to metallic iron. The crushing strength of VTM-CCB after reduction is found to decrease from 1800 N to 600 N correspondingly with increasing temperature from 600 °C to 1100 °C. The loss of the crushing strength correlates to the pyrolysis of the coal, the carbon gasification, and the reduction of iron oxides. The phase transformation of valuable elements during reduction could be described as follows: Fe3O4 → FeO → Fe; Fe2.75Ti0.25O4 → Fe2.5Ti0.5O4 → (Fe2TiO4) → FeTiO3 → (FeTi2O5) → TiO2. The softening-melting-dripping behavior and permeability of mixed burden is improved obviously with charging a certain amount of VTM-CCB. However, the precipitation of Ti(C,N) would deteriorate the dripping behavior of packed bed when VTM-CCB charging ratio exceeds 20%.
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mathematical simulation on Blast Furnace operation of coke oven gas injection in combination with top gas recycling
Steel Research International, 2016Co-Authors: Hongtao Wang, Mansheng Chu, Wei Zhao, Zhenggen Liu, Tonglai Guo, Cong Feng, Jue TangAbstract:In order to further improve Blast Furnace operational performance, reduce carbon emission, and increase gas utilization efficiency under only coke oven gas (COG) injection, a Blast Furnace Process of COG injection together with top gas recycling through tuyere injection (TI) and/or shaft injection (SI) had been mathematically simulated in this study. The effects of this new Process on in-Furnace status, operation parameters, and energy utilization are investigated by means of multi-fluid Blast Furnace model. The results show that compared with only COG injection, solid temperature slightly decreases and cohesive zone tends to move downward and narrow under simultaneous COG injection and top gas recycling. Meanwhile, the reduction degree of iron-bearing burdens evidently increases before entering cohesive zone due to more involvement of hydrogen into indirect reduction. Furthermore, the operation of COG injection combined with top gas recycling can achieve Blast Furnace ironmaking with low carbon emission, low energy consumption, and high efficiency. For example, hot metal productivity and corrected CO utilization efficiency under COG injection and TI increase by 13.87 and 6.95%, respectively. Additionally, carbon emission ratio and energy consumption decrease by 39.57 and 15.78%, respectively. Taking into account in-Furnace status, operational parameters, and energy consumption, the operation of COG injection and top gas recycling through TI is recommended as more feasible choice for the possible practical application.