Problems related to gas-solid reaction are important in many industrial applications, such as chemical and metallurgical processes. In this paper, a lattice gas cellular automata (LGCA) model with multi-substance and multi-energy is developed for the simulation of gas-solid reactions. Real-time concentration and temperature in the simulation zone are described by the evolution of particles marked with different substance states and energy states. To control the diffusion of gas particles, a collision probability is introduced according to the concentration gradient of different components. The chemical reaction is controlled by a reaction probability derived from the Arrhenius rate equation at macroscopic level. Furthermore, present LGCA model for reaction is validated by applying to the numerical simulation of a typical gas-solid reaction problem, i.e. the isothermal reduction process of iron oxides by reducing gases. Results show that the characteristics of flow and mass transfer in the gas-solid reaction system can be well captured, the detailed information of the interaction between gas particles and the solid particle can be obtained at meso-scale.. The rate of reaction increases with increasing the velocity, temperature and concentration of reactant gas and the simulation results agree well with experimental data, indicating that this model can be used to simulate a complex system involving the problems of fluid flow, heat transfer and chemical reaction.

The cokes with low reactivity index (CRI) and high coke strength after reaction (CSR) are generally regarded as good quality and acceptable for blast furnace (BF) operators. However, the cokes with greatly varied CRI and CSR can be used in large BF which can operate stably. Thus, it can be suggested that the CRI and CSR test should be disputed and distrusted. In this paper, various coke-quality parameters and measurement are proposed for a good understanding of cokes with greatly varied CRI and CSR. The developed coke-quality parameters are defined as an initial temperature of coke reaction (Ti), coke reaction rate at the coke weight loss of 25% (CRR25) and coke strength after reaction (CSR25) tested by not-isothermal to isothermal or isothermal experiment. The quality parameters of cokes explain why the cokes with higher CRI and lower CSR can be used in the blast furnace and ensure the BF operate stably.

For future progress, this presentation looks back on the research conducted in my laboratory with co-workers at Tohoku University.
As the main research subject, a three-dimensional transient mathematical model of the blast furnace was established considering complex transport processes. The model was being developed from two viewpoints of mathematical description/numerical computation and elucidation of elemental phenomena. The model developed has been used to simulate in-furnace phenomena with operation results for improving practical operations and for developing new technology.
The blast furnace model has been modified to simulate several the other packed bed processes. The modified model has been used effectively during the development of each process.
Some simulation results are explained for a super high-efficiency operation of BF and also for the other moving bed processes. Studies on the elemental phenomena are explained by gas-solid heat transfer coefficient and wet area of the irrigated packed bed.
Precise energy evaluation has the possibility to improve energy efficiency in the packed bed processes. Some results of exergy analysis are explained, which is applied to conventional and developing ironmaking processes.
Relating to BF, we studied on a rotary cup atomizer with packed bed process to produce granular slag and to recover thermal energy from molten slag and on methanol synthesis from BF off gas. These results showed the possibility to improve thermal efficiency and mitigation of CO2 emission.
To summarize above-mentioned items, the mathematical model is a useful tool to improve process efficiency and to develop new technology. However, accurate description of elemental phenomena is prerequisite. From these researches improvement of waste energy recovery and hydrogen application are favorable strategies to decrease CO2 emission from ironmaking industry to protect earth environment from global warming.
Keywords: Blast Furnace, Mathematical Model, Exergy, CO2 Reduction

Utilization of iron ore-carbon composite enables to play a significant role in reducing CO2 emission from the ironmaking process. However, its efficiency seems to be limited under the condition of the blast furnace. In this study, the effect of pressure from 0.1 to 8.0 MPa on the gasification and reduction of the composite was evaluated, and acceleration mechanism of reduction was discussed by mathematical simulation. The composite sample prepared using hematite reagent and graphite powder was heated up to different target temperatures at a heating rate of 0.167 �C/s under different pressures. Under atmospheric pressure, reduction of composite sample started at approximately 900 �C and completed at 1200 �C. Starting temperature of reduction decreased with increasing pressure. At 1050 �C, the effect of pressure on the reduction was most significant because gasification of graphite activated. To discuss the behavior, a mathematical simulation was carried out using Langmuir-Hinshelwood type gasification and unreacted-core models assuming that the temperature distribution in the composite sample can be neglected. Using the experimental data under atmospheric pressure, all parameters were decided, and the effect of pressure on the reduction was evaluated. Below 3.0 MPa, the calculated results were coincident with the measured one. It seems that reduction acceleration by increasing pressure is caused by an increase in the amount of adsorbed CO and O on carbon. Above 5.0 MPa and 1000 �C, however, the latter was higher than the former. The reason may be that the temperature distribution cannot be neglected under higher pressure.

Iron bath smelting reduction can conceptually produce hot metal with flexible raw materials such as ordinary iron ore fines and coal fines. There is, however, the issue of Post-Combustion Ratio (PCR) control in the Smelting Reduction Vessel (SRV). A PCR as low as possible is desirable for effective reduction of iron ore, but leading to a high coal consumption for heat supply. The ��clean use�� of coal via converting into gas fuel is now also a ��hot spot�� particularly in China. The current coal gasification processes have however the issue of difficult and water-consuming gas cleaning and tar treatment resulted from low-temperature gasification. Therefore, an iron-slag bath with three levels of coal/oxygen injection for simultaneous hot metal smelting reduction and coal gasification is proposed. A progressive zoned model is developed to calculate the heat and mass balances of the SRV and the overall process with ore pre-heating(reduction) and gas reforming units. The calculation results show that, with such a coal/oxygen injection design, not only the simultaneous hot metal production and coal gasification can be easily realized by maximum energy utilization within the process flow by applying a proper PCR in the SRV with corresponding coal/oxygen injections, but also the production capacities of hot metal and coal gasification can be flexibly combined with varying market supply and demand.
Keywords: smelting reduction, hot metal production, coal gasification, post combustion

In this study, a mathematical model for the analysis of particle temperature in the rotary kiln was developed. In this model, the motion of the particle bed in the rotary kiln was simulated by the discrete element method. In this method, the trajectories of all particles were tracked simultaneously with taking into account the contact forces among particles and between the particle and the kiln wall. Additionally, the temperature variations of all the particles were also tracked. In the particle heat transfer model, the convective heat transfer between the high-temperature gas and the particles and the radiative heat transfer between the kiln wall and the particles were considered. The heat transfer mechanisms were switched according to the location of the particle in the bed. With this heat transfer model, the distribution of the particle temperature was successfully calculated. And the variation of the temperature distribution with the progress of the particle heating was revealed.

Shaft furnace plays a very important role in the quantity and quality indexes of the COREX process. However, the model used to simulate burden distribution in the COREX shaft furnace can only simulate the single ring charging process, not the multi-ring charging process in practice. Therefore, a three-dimensional model of COREX shaft furnace is developed in this study based on discrete element method (DEM). The model simulates the charging process with four types of burdens together and then is used to investigate the effects of different charging matrix on the burden distribution. Results show that coke and flux roll away from the striking point, while ore segregates close to the striking point, and pellet always tends to move towards the central area. The base layer has a significant effect on burden stack profile, and the burden tends to accumulate in the center with the same ring number at each angle in the case of a flat base layer. The burden distribution is evener when the direction of charging is from inside to outside.

1. Introduction: Power device technology is advancing toward higher voltage, larger current, greater power density. However, the high power will induce large thermal stresses in the devices, which poses great challenges for the assembly of the devices and the packaging materials, especially the brittle ceramic substrates that provide functions of electrical insulation and heat dissipation [1,2]. Si3N4 ceramics have excellent mechanical and thermal properties, which are deemed as an attractive substrate material for high-power electronic device applications. Sintered silicon nitride has excellent toughness and thermal conductivity, which is mainly attributed to the alpha to beta phase transformation accelerating grain growth and densification during high temperature, Therefore, �Aalpha-Si3N4 powder is necessary for obtaining dense bulk silicon nitride. Then the purpose of this research is to synthesize high ratio alpha-Si3N4 powder using combustion synthesis method assisted by salt additives. 2. Experimental: The mixture of the starting materials (Si, Si3N4, and salts) was first subjected to dry planetary milling and then was combustion synthesized at a nitrogen pressure of 1 MPa. The alpha/beta ratio was estimated by the intensity ratio of the X-ray Diffraction (XRD). 3. Results: NaCl, MgCl2, and MgCl2∙6H2O were added in the raw mixtures for assisting synthesis of high ratio alpha-Si3N4. Among these three kinds of salts, NaCl showed the best appropriate additive in which 57.8 % alpha-Si3N4 was obtained when 30 mass% NaCl was added. Ball milling of the raw mixtures could increase the contact area of Si and NaCl by the dispersion of NaCl particles, 84 % alpha-Si3N4 was obtained after 120 min milling. References: [1] H. Okumura, Jpn. J. Appl. Phys. 2006, 45, 7565.[2] C. R. Eddy Jr., D. K. Gaskill, Science 2009, 324, 1398.

The practical application of magnesium hydride (MgH2) as hydrogen storage material (high capacity of 7.6 wt.%) has suffered mostly from the higher dehydriding temperature than 600 K. Alloying of Mg with Al has been considered one prospective way to overcome above problem owing to the fact that the hydriding products of Mg-Al alloys are MgH2 and Al (maximum hydrogen storage capacity of 4.44 wt.%), and the in-situ formed Al in metal can play an important role by its high thermal conductivity in the subsequent high endothermic dehydriding reaction, as well as the alloying between Al and Mg leading to the instability of Mg-H bond. In this report, the hydrogen storage property and the microstructure of Mg-Al alloys prepared by the process of combustion synthesis (CS) were investigated and compared to the process of induction melting (IM). The phase transformation during the CS process investigated by X-ray diffraction (XRD) analysis of the intermediate products, mainly, showed that the formation of Mg2Al3 alloy from elemental Mg and Al experienced four stages upon heating, accompanied by the appearance and transformation of Mg17Al12 alloy. Compared to the IM product, the CSed Mg2Al3 alloy exhibited superior performance in activation efficiency which could desorb hydrogen 2.70 wt.% at 573 K and the time needed to reach 90% saturation capacity was 0.78 h after the second activation process, however, it was 2.39 wt.% and 1.25 h for the IM product at the same conditions. Even after completely activation, the times required for 90 % saturation capacity of hydrogen desorption were 0.5 h and 0.9 h, respectively, for the CS and IM products. The mechanism on the superior performance was also discussed.

A series of experiments on sinter strength by MgO are carried out. The results show that, if chemical reagents MgO and CaO are added by MgO/CaO: Fe2O3=1:1 (molar ratio), the temperature of liquid formation for MgO��Fe2O3 is higher than that of CaO��Fe2O3. It can be explained by phase diagrams, this is the reason that the strength of sinter with higher MgO content becomes low. Then, the compressive strength of MgO��Fe2O3 and CaO��Fe2O3 are tested. It can be seen that the self-strength of MgO��Fe2O3 is lower than that of CaO��Fe2O3, which is another reason for the lower strength of sinter with higher MgO content. Impurity of chemical reagents has a neglectable effect on experimental, but the size of chemical reagents have big effects. In order to reduce this error, industrial flux is used instead of chemistry reagent. For magnesite or limestone, MgO/CaO:Fe2O3=1:1, the calcination temperature is 1150C. During the experiments, part of CaO in limestone melt, but the melting phenomena of MgO in magnesite is not obvious. This is a reason that the strength of sinter with more magnesite additive is lower. The experimental results of compression strength of industrial flux are similar with chemical reagents. The reason is that liquid formation temperature with magnesite additive becomes higher, which results in a lower self-strength of sinter with higher MgO (or magnesite).

The degradation behaviors of coke which reacts with CO2 and H2O were explored in our gas-solid reacting apparatus. It was observed that the temperature loss of coke with H2O in initial and violent solution were about 37�� and 125�� lower than that with CO2 respectively. The gasification rate of coke with H2O was about 1.27-3.16 times faster than that with CO2. But the difference of gasification rate will reduce with the lower temperature. The coke strength after reaction (CSR) with H2O was lower than with CO2 at 950��-1100��, but higher at 1200��. The coke��s apparent porosity and changing rate after reacting were both smaller with H2O than with CO2. It is mainly due to the reaction that occurred closer to the coke particle surface with H2O than with CO2 and making large pores appeared and pore wall eroded seriously at the coke particle surface.

A model for simulating the reduction of metallic neodymium from molten salts is presented. The model is based on the transport phenomena theory using the multiphase multicomponent concept. The model was formulated with basis on the Navier-Stokes equations coupled with the Maxwell's relations.
The model is useful for predicting optimum parameters of processing, as for example cell geometry and current density. Parameters such as cell efficiency and stability could be determined using the sensibility analysis under possible operational conditions of current density. The gaseous phase production and turbulence quantities are used to quantify the flow stability within the electrowinning reduction cell.

Japanese steel maker (four blast furnace steel makers and one engineering company) have been executed "Development of technologies for environmentally harmonized steelmaking process, 'COURSE50' "(CO2 Ultimate Reduction in Steelmaking process by innovative technology for Cool Earth 50) since February 2008. This project is a national project commissioned by the New Energy and Industrial Technology Development Organization (NEDO).
The target of COURSE50 is a mitigation of approximately 30% in CO2 emissions in the integrated steel plant. Two technologies are investigated, which are a) Reduction of iron ore by using hydrogen and hydrocarbon-containing coke oven gas additionally to curb CO2 emissions from blast furnaces, and b) Separation and recovery of CO2 from blast furnace gas with chemical absorption method and physical adsorption method by effective utilization of unused waste heat in steel works.
In case of a) the main task is conservation of heat balances of local parts and whole of blast furnaces. In case of b) the main task is how to improve the energy consumption of chemical absorption and physical adsorption, not only the improvement of agents and materials but also the process flow.
Keywords
CO2 emissions mitigation, Steelworks, Iron ore reduction using hydrogen, Separation and recovery of CO2 from blast furnace gas, Unused exhaust heat in steelworks.

Improvement of the elasticity of productivity of pig iron, decrease of the ratio of the reduction agents to reduce CO2 emissions, and the decrease of the coke ratio to reduce costs of pig iron are very important subjects of blast furnace operation.
To achieve these subjects, it is indispensable to keep the steady of the state of operation of the blast furnace.
Further, to keep the steady state of the blast furnace operation, it is important to know and visualize the inner state of the blast furnace.
Therefore, "a sensor that measures the state of the blast furnace," "a huge accessible database of measurement data," "a tool for visualizing the acquired huge data," and "a physical model that simulates an inner state of the blast furnace according to mathematical principles" have been developed.
Furthermore, a system that forecasts the future operation of the blast furnace based on the acquired data has been developed.
This report describes these developments.

The scale of metallurgical industry of China is very huge. The energy consumption, resources supplying and environmental impact of China are also face to severe challenges. The education programs and activities in universities towards undergraduates and graduates students concerning the sustainability of metallurgical industry in China are introduced in this paper. Since the beginning of the 21 century, the courses related to environmental protection, energy saving, ecology, eco-materials were opened. Even the school of metallurgical engineering was changed to the school of metallurgical and ecological engineering and undergraduate students major in ecological engineering were cultivated. On the other hand, key laboratories related to metallurgical engineering and resources utilization which affiliated to the Minister of Education were established in different universities. These laboratories provide platforms for educating and researching activities concerning sustainability of the metallurgical industry. The contents of those courses, activities and achievements of education programs and research including international exchange will be reported in details.

Induration process of oxidized pellets involves the oxidation of Fe3O4 and re-crystallization of Fe2O3. It is acknowledged that the re-crystallization of Fe2O3 in pellets is significant for pellets to obtain better ambient strength. In present work, the effect of MgO on the re-crystallization of Fe2O3 was studied. The results demonstrated that, as the mass fraction of MgO in pellets increased from 0% to 2.0%, the Fe2O3 crystallites would decrease gradually and distribute unevenly in pellets. Moreover, the crystallite connection of Fe2O3 would get weaker. In addition, MF-{(Fex Mg1-x) O � Fe2O3} phase would be generated in pellets. According to the quantitative analysis, with an addition of MgO content in pellets mentioned above, the volume-percentage of hematite decreased from 85.52% to 73.34%, and the magnetite and MF phase increased from 5.27% to 16.33%. Therefore, MgO plays a negative role in re-crystallization of Fe2O3. And the macro-performance of that was the compression strength (CS) of pellets which would be lower after the addition of MgO in pellets.

Faced with the raw material shortage of iron and steel industry, it is necessary to improve the use of lean ore such as carbonate iron ore. Carbonate iron ore is one of the main potential sources of iron with a large reserve in Liaoning and Shanxi provinces in China. Due to its significance and complex component, a new beneficiation process of peroxidation-reduction process for carbonate iron ore comprehensive utilization was proposed in the work. During the process, carbonate iron ore was completely oxidized into Fe2O3 first to improve ore grade and uniform ore composition and then reduced into Fe3O4 or �A-Fe2O3 which both had strong magnetism to separation. This work was focused on the oxidation part of the new process. Based on the fundamental characteristics of carbonate iron ore, the effects of roasting temperature and roasting time on the oxidation degree and weight loss rate were investigated by the single factor experiment. Besides, through the XRD and SEM analyses, the microstructure change together with phase transformation during oxidation were studied. It was shown that with the increased roasting temperature and time, the oxidation degree could rapidly increase to 99% while the weight loss rate increased to 14.67% and 12.00% respectively. The phase transformation during oxidation was proceeded as followed: FeCO3 �u Fe3O4 �u �A-Fe2O3 �u �A-Fe2O3 and the optimal roasting parameters to make carbonate iron ore oxidize completely included a temperature of 500�� and for a period of time of 30 min.

The steel industry in Japan has continuously challenged the development of energy saving technologies for achieving substantial reductions in CO2 emission for the past several decades. This report describes, firstly, typical Japanese energy saving technologies, such as TRT for the blast furnace, CDQ for the coke oven and the regenerative burner system for the heating furnace, which were developed and are now standard Japanese technologies in the steel works. Secondly, it explains advanced new heat recovery systems which have been developed such as the thermoelectric generation (TEG) system, which uses the waste heat of the continuous caster, and a system for recovery of heat from hot slag in the steelmaking process. Finally, the concluding remarks discuss current and future studies for the use of waste heat in the steel works that should be developed, such as heat storage systems and control systems for heat supply-and-demand management not only for the steel works, but also for linkage with other industries in order to realize cascade use of energy.

A fixed-bed membrane reactor was proposed to improve in-situ removal of water during methanol synthesis for enhancing the productivity of methanol. A quasi-dimensional reactor model based on the conservation of mass, energy and momentum with the non-ideal gas model was developed to simulate the synthesis process of methanol numerically. The effects of the membrane permeability, flow rate of reactants, inlet mole ratios, sweeping gas rate, reaction temperature and pressure on the productivity of methanol and profiles of different compositions were investigated. The simulation results show that the productivity of methanol in the fixed-bed membrane reactor might increase 11.38 % compared with the traditional fixed-bed reactor. The productivity of methanol would increase 15.21 % when sweeping gas rate in the sweep side increases from 0.1m/s to 0.3 m/s. A hot spot could be found close to the inlet of the reactor because of the strong exothermic characters of the reactions. These preliminary simulation results show that the fixed-bed membrane reactor technology with in-situ water removal is more efficient for methanol synthesis than a conventional fixed-bed reactor.

High iron gibbsite ore is a complex composition and microstructure ore, which features high iron content, high silica content, low alumina content and low A/S. In order to recover iron from high iron gibbsite ore, the process of metallized reduction and magnetic separation based on hot briquette agglomerates was researched systemically. The effect of reduction temperature, reduction time, and the mole ratio of fixed carbon to reducible oxygen (FC/O) on separation indexes was researched. The results show that, with the conditions of reduction temperature 1350��, reduction time 70 min, FC/O 1.0, and magnetic field intensity of 50 mT, about 87.01% of the iron could be removed from high iron gibbsite ore as metallic iron. Meanwhile, 86.21% of the aluminum are staying in a non-magnetic fraction as alumina. The phase transition of iron-bearing minerals during reduction process are obtained as follows: Fe2O3 �u FeO (FeO��Al2O3) �u Fe. The experiments and thermomechanical analysis show that the formation of hercynite (FeAl2O4) limits the reduction rate of iron oxides to metallic iron. A higher recovery ratio of iron could be achieved by adding the catalyst.

This paper describes exergy efficiency of steelworks, in which history of exergy efficiency was mainly examined together with validation of constructal law1). Since energy is conserved, true energy evaluation of steelworks should be done by exergy based on the second law of thermodynamics. Until now, several papers published on different steelmaking processes for comparative analysis. The constructal law was proposed in 1996 by Adrian Bejan as a theory of the generation of design in nature, in which evolution is generally explained by the improvement of exergy efficiency. However, no paper has never been published on exergy efficiency of steelworks, in spite of its scientific and engineering attractiveness. Therefore, the purpose of this paper was to study exergy efficiency of steelworks of various ages and to validate the constructal law. First, operating data of typical integrated steelworks was collected or reasonably simulated3). The steelworks with the annual production of 6 million ton was consisted of ten processes; coke oven, sintering machine, blast furnace, LD converter, continuous casting, hot rolling, plate milling, cold rolling, annealing line, continuous galvanizing line (CGL). Next, mass and heat balances for each process were carefully confirmed, and finally, simplified exergy flow diagram was illustrated. In the exergy flow, as time passed, the ratio of waste heat decreased and the ratio of power generation increased. The results were that exergy efficiency were 34.2% in 1970�fs, 41.1% in 1997 and 50.1% in 2030, showing evolution degree of steelworks in Japan. It also appealed a possibility that this methodology can apply to other chemical or metallurgical systems. <br />Keywords: Exergy, Steelworks, mass balance, heat balance

Due to a severe overcapacity, the Chinese steel industry is suffering from common operating difficulties. In order to reduce production cost and improve the competitiveness, it is propelled to use in great quantities raw materials with high zinc contents, including iron ores and retrieved wastes. As a result, the furnace state becomes unstable, the productive techno-economical indices go down and the target of decreasing cost is hard to realize. This paper focused on the behavior of zinc inside the blast furnace, the influences of zinc on raw materials metallurgical properties and the primary slag formation process as a particular, aiming at the formulation of right countermeasures for those blast furnaces that have severe zinc accumulation. An approach of soaking with zinc acetate solution was applied for adding zinc into the specimen of iron ores and coke. The low temperature reduction degradation property (the RDI index) and the reducibility (RI index) of sinter, the reactivity (CRI index) and strength after reaction (the CSR index) of coke were measured. The results showed with the zinc content increasing, for sinter, the RDI+3.15 and RDI+6.3 indices decreased and the RDI-0.5 greatly increased, while for coke, the CRI index decreased and the CSR index decreased. This implies that the zinc accumulation has negative effects on the burden column permeability and would also increase the fuel rate. The primary slag formation tests were conducted under simulating blast furnace conditions. The results demonstrated that the increase of zinc content rises the melt-down temperature, widens the softening �C melting temperature range, increases the value of permeability index S, makes the differential pressure of burden column fluently vary, and, when the zinc content exceeds a certain level, the zinc content in the dripping primary slag increases dramatically. This implies that a severe zinc accumulation would bring about worsening of the cohesive zone properties, increase the amount of zinc entering into the lower blast furnace, and, therefore, as a consequence, cause a serious damage to the hearth and cooling equipments.

The COREX process is the new ironmaking technology which has realized industrialization with lump coal instead of coke to get high-quality hot metal, and reduced the dependence on coking coal resources. So lump coal is the major fuel for COREX process, and the performance of COREX depends on its metallurgical properties. The descending process of Xinjiang lump coal was simulated and the evolution of metallurgical properties during the process was investigated by experiment. The results showed that the thermal stability was getting worse at the temperature of 300-500��. The mechanical strength of lump coal first decreased then became better with the temperature increase, and the most serious chalking interval was under 600-800�� condition. Moreover, the reactivity with CO2 decreased with its temperature increase. The metallurgical properties of Xiangjiang lump coal during the descending process depend on its pyrolysis reaction and microstructures evolution.

Carbon dioxide, a major component of metallurgical waste gas, could be comprehensively utilized to replace part of oxygen in vanadium-extraction converter. The thermodynamic theory and lab-scale experimental research on high efficiency vanadium-extraction in CO2 and O2 mixed blowing process have been undertaken. The results show that the oxidation of silicon and vanadium is rapid at the initial stage of CO2 and O2 mixed blowing process (0~6min), and the bath temperature rises quickly at speed of 10 K/min, then the bath temperature becomes gradually increased at speed of 2 K/min (6~15min) and decreases 7 K as CO2 blowing rate increases 10%. We found that when the proportions of CO2 from 10% to 15% in the mixed gas, the end point temperature of the bath can be controlled at below 1630 K, which is below the converting temperature for selective oxidation of vanadium and carbon. Meanwhile, the carbon oxidation rate and oxygen consumption of 15% CO2 blowing process are 12% and 8.5% less than pure O2 blowing process respectively. These findings suggest that introducing the technology of 15% CO2- 85% O2 mixed blowing could promote the extraction of vanadium, and keep carbon in semi-steel effectively.

Domestic and foreign experience shows that one of the key prerequisites for using pulverized coal injection (PC) in blast furnace smelting is ensuring that the combustion of the PC is completed within the tuyere zone. Thus, monitoring the degree of combustion of this fuel is an important problem. Various methods and instruments are used to analyze PC combustion in the tuyere zone experimentally.
It is proposed that the completeness of combustion of pulverized coal fuel injected into the hearth of blast furnaces be determined by petrographic analysis of the content of unburned coal particles in the top dust and slag and chemical analysis of the dust and slag.
Theoretical and experimental research on PC burning process under conditions of raceway have been carried out. Methods and designs for intensifying have been developed. Industrial tests of these methods have shown the possibility of a considerable increase of PC combustion degree under high PC consumption.
The industrial use of PC is accompanied by an increase in the amount of heat lost to the environment due to the intensified operation of the furnace. The injection of PC into the tuyere zone increases thermal radiation because of the formation of a luminous flame with a high emissivity. The result is overheating of the combustion products in the hearth, redistribution of temperature over the height of the furnace, and a significant increase in heat loss.
Effect of coal composition on its use efficiency in blast furnace operation has been examined. Technical and economical parameters of blast furnace operation when injecting PC from different coals have been studied. Recommendations for coal grinding and method of complex compensation for the changes in the technological regime have been developed.

Industrial applications for solids processing are commonly associated with the gas-solid particle reactions. Since the overall performance and productivity of the process depend on the treatment of gas-solid reactions, the proper reaction modeling is crucial in constructing an effective bed reactor model. The current study discusses the mathematical modeling procedure of bed type reactors that simplifies the bed structure and encompasses the particle reaction models referring to some industrial cases of solids processing.
Regarding the complex nature of the gas-solid particle reaction, various modeling studies have been conducted from the perspective of the single particle. The approaches hitherto proposed can be distinguished by the manner of the reaction progression, as well as whether it gives analytic or numerical solution. Among the models, the shrinking core model and the grain model are the two widely applied concepts.
The use of the reaction model in the bed process modeling should be based on the particle structure, reaction kinetics, and simultaneous heat and mass transfer effects. For instance, a discussion can be made about the frequent use of the shrinking core model for coke combustion in the pellet indurator modeling. Since the shrinking core model assumes a nonporous single particle, it may have limitations in representing the reaction progression in a pellet mostly attributed to pellet porosity and the sizes of a pellet and the coke lump. For this case, the grain model would become more advantageous.
Based on the discussion about single particle reaction models, the bed process modeling cases are presented. The typical simplifying approach using the porous media approximation and one or two dimensional numerical solution procedure could cover various applications, such as iron ore sintering, iron ore pellet indurator, mass-burn waste incinerator, and blast furnace.

During carbonization of coal in coking chamber, the gas pressure of plastic layer gives lateral force (coking pressure) against oven wall. Gas pressure is influenced by characteristics of coal and bulk density, excessive coking pressure damages oven chamber wall.
And it is thought that clearance between coke cake and oven wall decreases by the effect of coking pressure. As a result, coke cake extrusion force is increased. Increasing extrusion force causes enlargement of wall pressure during coke cake discharge.
Those wall pressures have a significant impact toward coke oven, especially aging coke oven.
Therefore, obtaining knowledge about effectiveness and mechanism of coking pressure to extruding force is important for prolongation coke oven life.
We changed the gas pressure of coal blend and measured gas pressure of charging coal and internal gas pressure, at 40 years age commercial oven. Furthermore, we measured the displacement of oven chamber wall during carbonization, by apparatus able to accurately measure the width of carbonization chamber. This report described these result.

Ultra pure ferritic stainless steels are Fe-Cr or Fe-Cr-Mo alloys bearing 11%~30% Cr and total C and N contents are limited to less than 0.015%. Ultra pure ferritic stainless steels are appreciated for their excellent uniform and localized corrosion resistance. Unfortunately, large inclusions such as Al2O3, TiOx, TiN, MgO and their complex in the steel are harmful to the surface quality, corrosion resistance and mechanical performance of the products. It is necessary to optimize the composition of VOD refining slag to absorb the inclusions in the practical production process. The influence of deoxidation process and VOD slag compositions on the behavior of inclusions during refining of Ti-Nb stabilized Fe-21%Cr ferrite stainless steels were studied in this work. The results indicated that the main inclusions in the Al-Si deoxidized samples were MgO��Al2O3. And the main inclusions after Ti addition were MgO��Al2O3-TiOx and Al2O3-TiN. After calcium treatment, the main inclusions became spherical MgO��Al2O3-CaO and Al2O3-SiO2-CaO combined with TiOx and TiN. As the basicity of refining slag was increased from 2.5 to 4, the number density of inclusions in the sample reduced, while the average particle size of inclusions increased. When the basicity of refining slag was 3.5, reducing Al2O3 content in the refining slag was conducive to decrease the number of larger inclusions. There were fewer inclusions and the size of most inclusions was distributed within 1 to 2�Im when the Ti-Nb stabilized Fe-21%Cr ferrite stainless steel was refined with the optimized refining slag with the composition of CaO-SiO2-20%Al2O3-10%MgO-5%CaF2 and the basicity of 3.5. The experiment about the influence of refining slag on the inclusions in Nb stabilized Fe-18Cr ferrite stainless steel without titanium was carried out, too. The refining slag which the composition of CaO-SiO2-10%Al2O3-10%MgO-5%CaF2 and R=3.5 had a good refining effect for Nb stabilized Fe-18Cr ferrite stainless steel.

Zr-based bulk metallic glass possesses is the highest potential as a structural material among metallic glasses. However, the production conditions have a great effect on its glass-forming ability (GFA) and mechanical characteristics. In this paper, an attempt is made to find the effect of a hereditary structure on the GFA and mechanical properties of a solid Zr52.8Cu29.1Ni7.3Al9.8Y1 bulk metallic glass in order to evaluate the possibility of using precursor, solid binary alloys that have a hereditary relation to the liquid phase. It is found that the GFA and stability of Zr52.8Cu29.1Ni7.3Al9.8Y1 bulk metallic glasses prepared in the hereditary process are higher than conventional samples and increase with the increasing quenching temperature. At a quenching temperature of 1523 K, the hereditary process can improve the supercooled liquid region ��Tx from 33 K to 55 K and the compressive strength from 1555 MPa to 1652 MPa.

H2 injection through the shaft into blast furnace (BF) is a potential option for further reduction of CO2 emission from BF. Utilization of H2 promotes reduction reaction of burdens, but its influence on their reduction disintegration behavior has not well clarified in detail. In this study, therefore, we have investigated such influence on the iron ore sinter, and self-fluxed and acid pellets and tried to specify dominant factors governing the reduction disintegration behavior.
Two series of experiments were conducted: mass ratios of particles under 3mm in size were measured as RDI after the reduction of burden samples at 823K by the gas mixtures of N2-CO and N2-H2, and observation of the reduced samples with an optical-microscope and an electron probe micro-analyzer. Further, using the measurement results, stress, strain energy and crack area generated during reduction were calculated and formation mechanism of cracks was examined.
RDI increased for higher H2 condition and reached to 15 mass% when self-fluxed pellet was reduced with gas mixture of 70%N2-30%H2. Such an increase was larger than that expected compared to the standard RDI test condition without H2. Sample observation revealed that the reduction mode governed generation of the under size, that is, disintegration was promoted by the reduction with non-topochemical mode. This can be explained by the influence of crack formation and its propagation. In case of reduction with topochemical mode, cracks generated in a concentric fashion. Meanwhile, reduction with non-topochemical mode tended to generate cracks in radial direction, which causes pellet chipping and further degradation. Calculated crack area with topochemical mode was higher than that with non-topochemical mode. It indicates that disintegration does not much progress when crack area is less than the limit value, but it drastically proceeds when it exceeded a limit value.

In Wakayama coke plant, briquette coking process is adopted for coal preprocessing. Briquette coking process enables making high strength coke and increasing the use of low rank coals by high apparent density. However on the conveying process from briquette machine to coal tower, briquettes are broken down by drop impact. As a result, the collapses of briquette cause degrade in coke strength. Therefore, it is necessary to make high strength briquette which is capable of withstanding drop impact.
Our purpose is to make high strength briquette by optimizing kneading and briquetting conditions.
At first, a correlation between general evaluation methods of briquette strength index and collapse behavior of briquette on conveying process was checked. On the basis of the prior result, kneading temperature and linear pressure were optimized to improve briquetting yield rate and convey yield rate.
In terms of briquetting yield rate, it declined drastically below a certain linear pressure at any kneading temperature. On the other hand, convey yield rate was significantly influenced by kneading temperature. High kneading temperature could improve convey yield rate. However if kneading temperature was insufficient, high linear pressure caused degrade of conveying yield rate.

The viscous behaviors are the important physicochemical properties of slag which can affect the stability and the production cost of the iron-making process. In this study, the effects of MgO/Al2O3 on the viscous behaviors of titanium-bearing slag were investigated by rotating spindle method. The variation of viscosity, the activation energy for viscous flow and break point temperature of slag was analyzed. Besides, in order to connect the viscosity and the slag structure, Fourier transform infrared spectroscopy (FTIR) was performed on as-quenched slags. The results showed that the viscosity of slag was decreased as increasing MgO/Al2O3 content from 0.72 to 1.01. However, the break point temperature was increased, and the activation energy for the viscous flow was initially increased and subsequently decreased. FTIR results revealed that the polymerization degree of complex viscous units in slag decreased with an increase of MgO/Al2O3, which clarify the variation mechanism of viscosity for the different MgO/Al2O3 titanium-bearing slags.

The fate of nanoparticles into the environment are of special interest due to their interactions with the ecosystems. In this paper, the stability and transport behaviors of hazardous nanoparticles into soil landfills are studied using experimental and numerical procedures to simulate the effects of silica nanoparticles natural suspensions during percolation into soil layers of municipal waste landfills. Stabilized suspensions of nanoparticles oxides containing silicon (NPSiO2) and titanium (NPTiO2) were prepared. Thus, leaching experiments results were confronted with numerical prediction within soil column simulating landfills layers to simulate the capture and attenuation of these nanomaterials into municipal waste landfills. It was found that the solution containing NPSiO2 increases the stable concentration of the titanium oxide and strongly decrease the natural soil layer effectiveness to capture the hazardous nanoparticles.

The pellets induration process travelling in the strand of the furnace plays an important role on the final properties related to the mechanical strength and reducibility. The prediction of these properties taking into account the thermal history and the phase transformations is of special interest. In this study, a model based on the macroscopic and microscopic behavior of the individual pellets is proposed. The model is able to predict the thermal history of the bed and the individual pellets during the entire travelling distance within the furnace. The model is confronted with experimental results for individual pellets and the industrial data. Afterwards, the model is used to predict the effect of the increasingly use of biomass as solid fuel in the interior of the individual pellets and the furnace zones. Simulation results indicated that increasing the biomass solid fuel the carbon emission is reduced but with a decrease in the mechanical strength and increases on the reducibility.

The production of direct reduced iron (DRI) using hydrogen instead of carbon monoxide helps to reduce CO2 emission and slows down global warming. The reduction of hematite occurs in two-step as Fe2O3-Fe3O4-Fe when temperatures are below 570 ��.A better understanding of the two-step reduction kinetics of hematite with hydrogen will reveal useful fundamental information for the industrial applications and promotes the development of energy-saving technologies for iron making. The reduction of iron oxides into iron is complex because the process is heterogeneous and several elementary reactions take place simultaneously. It is hard to figure out the reduction kinetics under fluidization in a fixed bed reactor such as in a thermogravimetry analyzer (TGA) which suffers from the limitations of heating rate, external diffusion, thermal pretreatment before a reaction occurs. In this study, the reduction kinetics of hematite to metallic iron with hydrogen at temperature 300��-550�� are experimentally investigated in a micro-fluidized bed reaction analyzer (MFBRA), developed by the Institute of Process Engineering (IPE), Chinese Academy of Sciences (CAS) to study the kinetics of fast gas-solid reactions. Results indicate that the low-temperature reduction of hematite with hydrogen can be well captured by a two-step kinetics method based on Johnson-Mehl-Avrami (JMA) model using statistical analysis tools in the Statistical Product and Service Solutions (SPSS). It shows that the reduction process can be interpreted as two elementary reactions (i.e. hematite-magnetite and magnetite-iron), which proceed in parallel with different controlling mechanisms as well as with different time dependencies. The kinetics parameters, i.e. activation energy and pre-exponential factor, are determined for each elementary reaction. The contribution of each individual reaction to the whole reduction process is further discussed. The results also suggest that the reduction of hematite to magnetite takes place fast and dominates the initial part of the entire reduction while the reduction of magnetite to iron plays a less important role in the initial stage but controls the whole reduction in the late stage. The conclusions obtained in this study are comparable with that in the literature and indicate that the two-step kinetics model is able to capture the properties of both elementary reactions and the integrated reduction process, providing an analysis strategy for revealing detail characteristics of the low-temperature reduction of iron oxides.

Indonesia is the world's major supplier of nickel ore, particularly the type of laterites nickel ore. Carrying nearly 25 % of the world's nickel ore is supplied from the country. But on the other hand, the price of Indonesian nickel ore is largely determined by developments in the world price of nickel metal. Almost all products of nickel ore from the mines in Indonesia is still exported abroad in the form of ore raw materials that do not provide high added value. Therefore, the increase in value-added nickel is a very logical and will benefit for the country. A process has been developed whereby nickel laterites can be smelted in MBF to produce NPI. The production capacity is 840kg NPI per day for 1,6%Ni laterite nickel ore. Anthracite Coals are used as reductor and dolomites are used as a flux in MBF. All raw materials have 7 cm of diameter and entered into MBF in layers. The air blast supplied with fresh air without preheating and oxygen enrichment. All of the raw materials are coming from the country itself. The MBF off-gas is used in tunnel kiln combustion as fuel addition for nickel laterite ore pre-treatment. This pretreatment process allows conditioned ore entering MBF which has a lower moisture content. The NPI produced from this MBF has higher nickel content (20 � 25%Ni) and the average Ni yield is 70%. MBF uses single tap hole for tapping process. After tapping process, the product (hot metal and slag) are cast in three different height of mould. So it allows the separation of hot metal and slag in the last mould. After solidification, then the product are crushed for hot metal and slag separation.
KEYWORDS: Laterites nickel ores, nickel pig iron, mini blast furnace.

This paper presents a mathematical model able to predict the influence of soft-melting properties of the blend of raw materials used in the iron ore sintering process in the kinetic formation of calcium ferrite and di-calcium ferrite constituents. The model is based on the simultaneous solution of transport equations of Momentum, energy and chemical species in multiphase multicomponent systems coupled with the chemical reactions kinetics and phase transformations that occur within the sinter bed. The numerical solution is obtained using the finite volume method and the model is validated using monitoring data from an industrial scale sintering plant. After validation, the model was used to predict processing conditions using raw materials with different soft-melting properties. Results indicate that the temperatures of starting soft-melting, shrinkage and melting range are the main parameters to be controlled in order to attain liquid phases formation responsible for conferring good mechanical and reducibility properties for the sinter product. In this study was found that raw materials with high soft-melting temperature and wilder temperature of mushy zone could decrease up to 30% the calcium ferrites formation and hence deteriorates the metallurgical properties of the sinter.

The extent of hearth cooling is of paramount importance in determining the feasible duration of an extended blast furnace maintenance shutdown. Traditionally, measured refractory temperatures at the hearth side walls and pad are used to indicate the extent of hearth cooling during a shutdown. However, if the temperature trend is unusual, i.e. it does not follow any historical records, it is difficult to predict realistic hearth conditions through the refractory temperature alone, which generates uncertainty during the furnace shutdown. In this respect, numerical simulation of hearth cooling may be very helpful in providing detailed insight into the internal condition of the hearth including liquid bath and hearth refractory. In this study, based on a solidification front tracking approach, a transient numerical model had been established considering the effect of solidification enthalpy of liquid iron in both the coke bed and coke free layer to monitor the progress of hearth cooling in BlueScope Ltd�s Port Kembla No. 5 Blast Furnace. The model was firstly verified by comparing the refractory temperature to the calculated data during shorter duration furnace shutdowns (typically 1-2 days). It was then applied to estimate the hearth condition in an extended shutdown period (typically, 5-6 days). The calculated refractory temperatures were reasonably matched with the measured data over the extended shutdown period. In particular, the mushy zone (defined in terms of a temperature range around the 1150�C isotherm) was tracked � this allowed visualization of the temporal variation of refractory temperatures and the extent of liquid bath cooling during a number of shutdowns, providing useful guidance for furnace engineers. Additionally, the model can be applied more broadly to monitor hearth conditions, such as in the case of an abnormal stoppage of the furnace.

Titanium-bearing wire injection through tuyere has been proved to be available for maintaining eroded hearth of blast furnace. In the current work, a three-dimensional hearth model based on computational fluid dynamics is proposed to simulate the migration path and concentration distribution of titanium compound in hot metal. The model considers the effects of porous medium under the conditions of the laminar flow as well as floating and inactive deadman. Based on the modeling results, the migration path and concentration distribution of titanium compound in hot metal is varied widely with different injection positions. The different floating heights the deadman are analyzed and the results shown that titanium compound distribution is similar when the floating heights are 0 m, 0.3 m and 0.6 m respectively. The model is expected to be helpful to provide some suggestions for hearth protection and prolong the campaign of the blast furnace.

A multiphase mathematical model based on the transport equations of momentum energy and chemical species is improved to take into account the inject of rich hydrogen gas into the mini blast furnace based on biomass technology. A base case of charcoal mini blast furnace operation is simulated and compared with industrial operations parameters. Thus, newly operation techniques are proposed to investigate new technologies of low carbon intensity. In this study, a parameter of carbon intensity is proposed to compare the new technologies based on the gas injection into multilevel tuyeres. The simulations results indicated that carbon intensity parameter can be reduced lower than 40%, which represents clearly new possibilities for the reduction step using mini blast furnace technologies and could open new possibilities for the reduction technology.

The classical route of iron and steel production based on agglomeration-coke-blast furnace-BOF paradigm has served very well the global economy in the last several hundred years and continues to be a dominant one in the beginning of 21st century. However at the present new conditions where environment protection and sustainability have become a necessary requirement for any technology, the drawbacks of this route such as CO2 contamination, environmental pollution and high specific energy consumption have surfaced.
Several initiatives have undertaken to reduce CO2 emission from iron and steel industry. They include ULCOS European program that aims to decrease by 50% the CO2 emitted per ton of steel by 2050 and COURSE-50 Japanese program that aims to fully prevent CO2 emission in the atmosphere during metal production processes. Unfortunately, as of now, these goals have not been achieved and more work is needed. The reason for this is the fact that despite numerous modernization during the years in the industry there is a physical limit on specific carbon consumption as a reductant and energy supplier which might raise the question if this classical technology has no more potential of development in this direction.
One alternative of the above is the development of radically new, disruptive, energy-efficient and environmentally friendly technologies that exclude agglomeration, coke production and blast-furnace. This is because attempts to solve iron and steel environmental and energy problems based on existing processes without changing its core essence might give no good results.
In this framework, a radically new electrometallurgical iron and steel making technology is presented in this paper. This technology named ORIEN, developed, tested and patented has the potential to solve the environmental problems of the iron and steel industry and assures energy saving, cost reduction and increase of the steel quality. The new electrometallurgical complexes like ORIEN may become a basis of a new paradigm shift in iron and steel production.

High-chromium vanadium�Cbearing titanomagnetite containing 0.61wt% Cr2O3 was a special iron ore due to its complex mineral composition and special material characteristic. It was important to clearly know its specific processes including oxidation and reduction for efficiently utilizing it as much as possible. Naturally, this work was focused on the oxidation process of this special iron ore. Based on the fundamental characteristics of high-chromium vanadium�Cbearing titanomagnetite, the pellet samples were prepared, meanwhile, the effects of roasting temperature and roasting time on the compressive strength of pellet, microstructure of pellet, phase transformation, and oxidation consolidation during oxidation process were investigated systematically. It was shown that the oxidation of high-chromium vanadium�Cbearing titanomagnetite was not a simple process but a complex one. With the increasing roasting temperature and time, the compressive strength of oxidized pellet was improved and the change rule of compressive strength was described as three sections corresponding to the oxidation consolidation process of high-chromium vanadium�Cbearing titanomagnetite pellet respectively. The phase transformation during oxidation should be proceeded as follows: Fe3O4 �u Fe2O3; Fe2.75Ti0.25O4 �u Fe9TiO15 + FeTiO3 �u Fe9TiO15 + Fe2Ti3O9; Fe2VO4 �u V2O3 �u (Cr0.15V0.85)2O3; FeCr2O4 �u Cr2O3 �u Cr1.3Fe0.7O3 + (Cr0.15V0.85)2O3. The oxidation consolidation process was divided into three stages: oxidation below 1173 K; recrystallization consolidation at 1173 K��1373 K; particle refining recrystallization-consolidation by the attending of liquid phase at 1373 K��1573 K. To obtain the high-chromium vanadium�Cbearing titanomagnetite oxidized pellet with a good quality, the rational roasting parameters included a roasting temperature of 1573 K and a roasting time of 20 min.

In reaction models for gaseous reduction of iron ore agglomerates, the formations of both unreacted-core shrinking (UCS) model for one interface and UCS model for three interfaces and the developments of multi-stage zone-reaction models without and with considering solid-state diffusion are summarized; these models are used mainly for pellets but sometimes used for sinter. UCS model for six interfaces in consideration of quaternary calcium ferrite reduction process is newly developed for sinter. Comparisons of these reaction models for pellets and sinter are carried out by using experimental data on gaseous reduction of these iron ore agglomerates.
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[54] T. Yagi and Y. Ono: A Method of Analysis for Reduction of Iron Oxide in Mixed-Control Kinetics, Trans. ISIJ, 8 (1968), 377-381.
[55] N. Oyama, Y. Iwami, T. Yamamoto, S. Machida, T. Higuchi, H. Sato, M. Sato, K. Takeda, Y. Watanabe, M. Shimizu and K. Nishioka: Development of Secondary-fuel Injection Technology for Energy Reduction in the Iron Ore Sintering Process, Tetsu-to-Hagan� (in Japanese), 97 (2011), 510-518; ISIJ International, 51 (2011), 913-921.
[56] T. Murayama, T. Usui, M. Naito and Y. Ono: Kinetic Analysis on Gaseous Reduction of Agglomerates, Part 2, Rate Parameters Included in the Mathematical Model for Gaseous Reduction of Agglomerates (in Japanese), Tetsu-to-Hagan�, 80 (1994), 493-500.
[57] M. Naito, T. Murayama and T. Usui: Kinetic Analysis on Gaseous Reduction of Agglomerates, Part 3, Application of Gaseous Reduction Models for Agglomerates to Blast Furnace Analysis (in Japanese), Tetsu-to-Hagan�, 80 (1994), 581-586.
[58] Discussion Sessions of High Temperature Processes: �Improvement of the iron ore sintering process aiming at lowering its environmental load and energy saving (in Japanese)� {the final report of the Research Project on �Technological Principle for Low-Carbon Sintering� (Chairman: E. Kasai)}, CAMP-ISIJ, 25 (2012), 599 � 642, CD-ROM.

This paper describes recent developments in combustion synthesis (CS) for producing hydrides, nitrides, oxide and alloys during the last two decades which basically uses exothermic heat efficiently among powders and gas. It is mainly characterized by self-propagation of a high temperature synthesis (SHS) wave, minimization of productive energy, short processing time, non-equilibrium phase, high purity product, simple equipment and high productivity. In particular, combustion synthesis of hydrides1-3) (Mg2NiH4, LaNi5H6, FeTiH2, MgH2), nitrides4) (Si3N4, AlN, SiAlON), oxides (TiOx, FexO, MnxO, ABO3) and alloy (Fe2VAl) under the control of atmosphere has been recently reported. Synthesis of a non-stoichiometric compound such as TiOx by control of powder mixing ratio is also attractive from the viewpoint of defect design. The survey on major database revealed that the products reported covers many state-of-the-art energy conversion materials such as photo-catalyst, catalyst for the diesel engine, semiconductor, dielectrics, battery-related material, hydrogen storage alloy, thermoelectric device, refractory, hard material, and sinter for ironmaking. In conclusion, combustion synthesis will be reviewed from three viewpoints of exergy engineering, process engineering, and material science, together with companies established in Japan. <br />Keywords; combustion, process, energy, hydrogen, nitrogen, oxidation, industry<br />Reference)<br />1) Hydriding Combustion Synthesis for the Production of Hydrogen Storage Alloy, T. Akiyama, H. Isogai and J. Yagi, Journal of Alloys and Compounds, 252(1997), pp.1-4. [I.F. 1.035]<br />2) Hydriding Combustion Synthesis of TiFe, I. Saita, M. Sato, H.Uesugi, T. Akiyama, Journal of Alloys and Compounds, 446-447(2007), pp.195-199. [I.F. 1.455]<br />3) Self-ignition combustion synthesis of LaNi5 utilizing hydrogenation heat of metallic calcium,<br />N. Yasuda, S. Sasaki, N. Okinaka, T. Akiyama, International Journal of Hydrogen Energy, 35(2010), pp.11035&#65533;11041. [I.F. 3.945]<br />4) A New Route to Synthesize beta-Si6-zAlzOzN8-z Powders, K. Aoyagi, T. Hiraki, R, Sivakumar, T, Waranabe, T. Akiyama, Journal of Alloys and Compounds, 441(2007), pp.236-244. [I.F. 1.455]

The last decade was turbulent for the steel industry. The reorganization of steel industry across borders has progressed and the increased demand for steel products has made the price of raw materials such as iron ore and metallurgical coal more volatile than ever. Ironmaking technology division in NSSMC has been exposed to global competition and has tried to cope with these changes and to increase its international competitiveness by developing such technologies as utilization of lower grade raw materials, productivity enhancement, measures for energy conservation and reduction of CO2 and NOx emission and so on. This paper describes the recent progress in ironmaking technologies in NSSMC.

Recent Research Trend will be presented for nanoparticulate advanced functional ceramics materials, in particular, in our laboratory.&#12288;Here, we will focus our attention on transparent conductive oxides (TCO). Among TCO, the indium-tin-oxides (ITO) thin film is generally prepared by the sputtering process with ITO target, but only 20% of ITO yielded from the target is deposited on the substrate. Namely, about 80% ITO is exhausted by the deposition elsewhere far from the substrate. The recycling process of indium is limited so that ca 20% ITO of the starting material is lost without any recovery. Even if the recycling of ITO has been carried out in this process, we should prepare ITO target of 5 times more than apparent use of ITO on film. If we change it to printing process from the sputtering, the reduction in ITO use is expected as ca. 50%, considering the increase in film thickness by printing. Our target technology also includes ITO nanoink for the project. As a result, monodispersed ITO nanoparticles (NPs) with a cubic shape were fabricated by using quaternary ammonium hydroxide-assisted metal hydroxide organogels. These NPs have perfect uniformity in size with beautiful shape, and perfect single crystalline structure including Sn. As we were attempted to make a thin film with ITO nanoink, it was successfully fabricated below 200 nm in thickness and the resistivity was drastically decreased below 1.0 x 10-3 ohm cm after heat treatments. GZO nanoink as substitute of ITO has also been developed.

The development of technology for the production of ironmaking resources with high-reactivity and low reduction disintegration is necessary. In this study, we thus first prepare an iron oxide/carbonaceous materials composite (carbon-containing pellet) from coke oven gas (COG) tar and a limonite-based pellet (LP), in which the carbonaceous material is completely filled into the pores of the pellets. The crushing strength and reduction behavior of the composite prepared from LP and COG tar are then investigated. The peak of the pore size distribution profile, at around 2 nm, observed in the as-prepared LP completely disappears for the composites prepared, and the SBET and VBJH values are < 1 m2/g and < 0.01 cm3/g, respectively. The crushing strength of the composites becomes 10 daN from 1.0 daN. Carbonaceous material derived from tar is detected on the surface of the composite particle, as well as inside the particle, and the C content in the composite is 22 mass%-C. When the composites prepared are heated in He and 55%H2/He, the evolution of CO, CO2, and H2O begins at approximately 400 and 500 �C, respectively, and the formation profiles give a large peak at approximately 800&#8722;900 �C. The extent of reduction of the composites at 1000 �C is 85&#8722;95 %. The crushing strength of the dehydrated-LP decreases drastically up to a reduction extent of 50 %, whereas the strength of the composites is maintained at a reduction rate up to 50 %.

The energy and environment issues have been paid more and more attention by the iron and steel making industry. During the past few decades, a number of new breakthrough technologies for iron and steel making have been developed by different countries to achieve a significant reduction in CO2 emission and energy consumption. HIsarna is one of the technologies which belongs to ULCOS (Ultra Low CO2 Steelmaking) program in Europe and aims to cut CO2 emission by 80% per ton of steel with Carbon Capture and Storage (CCS) technology. HIsarna process makes use of coal and iron ore fines directly as raw materials instead of coke and pellet. It combines a melting cyclone and a smelting reduction vessel (SRV) into a single smelting furnace. The fine hematite ore undergoes a series of complex chemical and physical changes while descending in the melting cyclone such as thermal decomposition, gas-solid particle reduction, melting, and gas-molten particle reduction. It has been found that the hematite particles can melt down quickly in the reducing gas when the temperature is higher than 1650K. The objective of this study is to investigate the reduction kinetics of in-flight molten hematite particle at the typical conditions of melting cyclone. The experiments have been carried out by using a high temperature drop tube furnace. The reduction was accompanied by thermal decomposition reaction during the first 210ms. The kinetic analysis showed that the unreacted shrinking core model could be used to characterize the reduction and thermal decomposition process. The activity energy of the gas-molten particle reduction was about 156kJ/mol-1.
Keywords: HIsarna process, gas-molten particle reduction, thermal decomposition, reduction kinetics, high temperature, fine hematite ore

It is vitally important that guide sintering ore blending work by deeply acquiring the room and high-temperature characteristics of iron ore. For high-temperature characteristics, particularly, they could reflect the high-temperature behaviors and effects in the process of sintering. In this paper, the 5 kinds of basic sintering characteristics (assimilation, fluidity of liquid phase, SFCA generative capacity, strength of melting phase and strength of joined crystal) and two new proposed high-temperature characteristics (fusion and liquid absorbability) were introduced, respectively. And then, through the experimental investigation, the optimizing ore blending technology base on the principle of complementary ore blending of assimilation and fluidity of liquid phase characteristics and large particles divided adding technology based on the control of liquid absorbability of larger limonite particles were presented. The result of sinter pot test indicates that good sintering indexes were obtained, which proves the superiority of ore blending based on high-temperature characteristics of iron ores. Finally, the future prospects of optimization technology of iron ore blending for sintering were discussed from two sides, one is the sintering optimization expert system based on the high-temperature characteristics of fine iron ores, another is the sintering process optimization based on the deterioration of fine iron ores.

Size distribution, microstructure and high temperature properties of titanium sands before and after grinding are researched in the paper. Sinter pot tests and scanning electron microscope and energy dispersive spectrometer (SEM-EDS) tests are conducted to identify the influence and mechanism of titanium sands to sinter quality. The research shows that the micro-morphology of titanium sands become more irregular after grinding, and the granulation of titanium sands get strengthened. Meanwhile, the high temperature characteristics of sintering are different with the common iron ore fines: with titanium sands becoming finer, the assimilation temperature improves for 21 ��, and the liquid phase fluidity index decreases by 0.35 at 1280 ��; the reason caused the difference is that more perovskites are formed by CaO and titanium sands after grinding which can hinder the assimilation reaction and get liquid phase more sticky. Sinter pot test is conducted, and reduction index (RI) of sinter produced by the same proportion of titanium sands with a different distribution in blends improves by 3.8 % as titanium sands getting finer. The reasons are that titanium sands are distributed more uniform in the mixture after grinding, resulting in the increase of phase particles containing titanium in sintered ores, and many micro-cracks emerged in the reduction which is in favor of reducing gas diffusion.

Traditionally the self-reducing process for ironmaking relies on cold bond agglomeration for getting the mechanical strength and the main binder is normally Portland Cement. This binder confers excellent cold strength after curing, but loses it, at high temperatures around above 1173K, aggravated with reduction reactions. This is the main problem of self-reducing processes. This paper analyzes some peculiarities of self-reducing process for production of ferro-alloys, mainly for ferro-manganese and ferro-chromium. The reduction phenomena for ironmakling and ferro-alloys productions are quite different, which may affect negatively or positively the strength at high temperatures and the reduction rate of these carbon-ore composite agglomerates.

Through the support of reconstruction from disaster of great earthquake for the eastern Japan in 2011, �Iron technology and history forum� of the Iron and Steel Institute of Japan received the request of study of molten iron and steel production in low height furnace with iron sand smelting and started up the �IMPRESSIVE�, the research workshop of �Iron Manufacturing Process Engineering and Scientific Study in Vetus Iron� in 2013.
The research workshop of �IMPRESSIVE� has been studied the process engineering for ironmaking with iron sand under dynamic states in low height furnace. And it was discussed that by comparing low height furnace with iron sand smelting to blast furnace, the dynamic state was characterized by the transfer from an equilibrium state to the quasi-equilibrium state with coupling reaction in dead-man and hearth.
In this report, the formation process of flow out of hot metal iron from tapping hole and the factor were considered particularly, and new researching field of the iron manufacturing process was examined.

Traditionally, solid-fuel such as coke or anthracite has been used in the sintering process in the past. Solid-fuel is mixed with iron ores and limestone, after that its combustion heat promotes sinter reaction. As the quality of sintered ore can be ascribed to the mineral structure and constituents, the heat control in the sintering bed is a significant technique to yield the high quality sintered ore.
Temperature control in the sintering bed was studied for ordinary sintering method with solid-fuel. For example, the high mixing ratio of solid �fuel increases the temperature in the sintering bed, and the size of fuel can control solid-fuel segregation in the bed height direction.
On the other hand, JFE Steel Corporation has studied the new heat control technique by gas-fuel or liquid-fuel with different combustion behavior from solid-fuel. As the results, JFE Steel Corporation developed a new technology for injection of hydrocarbon gas fuel in sintering machines, �gSuper-SINTER (Secondary-fuel Injection Technology for Energy Reduction)�h. It was successfully applied to several commercial sinter plants for the first time in the world.
With �gSuper-SINTER�h technology, it is possible to extend the optimum temperature zone by injecting a hydrocarbon gas fuel from the upper side of the charged raw materials as a partial substitute for coke breeze. As a result, the energy efficiency of the sintering process was greatly improved, and it has been achieved to reduce a significant amount of CO2 emissions.

Crystal nucleation plays a decisive role in determining the crystal structure and size distribution of the crystal inclusions in molten steel. Until now, the knowledge does not yet provide a clear picture about the pathway leading �A-Al2O3 inclusion from molten steel. Especially, it is unclear that the structure and thermodynamic properties of prenucleation alumina clusters and cluster aggregates in the nucleation process. In the current work, the thermodynamic equilibrium experiments and model studies on the aluminum deoxidation reaction in liquid iron since the 1950s are summarized systematically, moreover, the industrial experimental data of aluminum deoxidation refining are compared with the thermodynamic equilibrium curves. It is revealed that the existence of metastable alumina phase in aluminum-deoxidation process, based on thermodynamic properties of metastable alumina phase and the difference in terms of the experimental results and equilibrium curves. Furthermore, the thermodynamics of metastable prenucleation alumina clusters, the excess oxygen and supersaturation degree of Al and O for nucleation are analyzed by the two-step nucleation mechanism. The prenucleation analysis suggested that alumina clusters gathering into cluster aggregates are the restricted step of �A-Al2O3 nucleation and a decisive factor to reduce the nucleation rate. In order to control the size distribution of alumina inclusions, based on the thermodynamic point of view, it could be effective to separate alumina clusters formation and the growth of �A-Al2O3 crystal with size more than 10 nm.

Arsenic existing in iron ore is one of the harmful elements because it is easily reduced and transfer into molten iron. The removal of arsenic from molten iron is relatively difficult, resulting in the iron ore containing arsenic is not convenient to be used in large scale. In view of the minor usage amount of low arsenic-bearing iron ore in ironmaking process, the removal of arsenic from low arsenic-bearing iron ore is an imperative work. In the present work, the removal of arsenic and sulfur from low arsenic-bearing iron ore by roasting has been investigated in different atmosphere systematically. The effects of roasting time and temperature on the removal efficiency of arsenic and sulfur by the roasting process were studied and the optimum roasting conditions were obtained. The arsenic and sulfur in low arsenic-bearing iron ore containing arsenopyrite can be removed effectively by the roasting method. The removal ratio of arsenic and sulfur in low arsenic-bearing iron ore increases obviously as increasing the roasting time within 1 hour and roasting temperature within 1400 K, and decreases with temperature increasing to 1500 K. The optimum conditions for arsenic and sulfur removal is roasting at 1400 K for 1 h in vacuum atmosphere and the removal ratio are 89.90% and 96.30% respectively.

As the second largest producer of oil palm biomass in Malaysia has been pyrolyzed for primary products of a bio-oil and significant by-product of char. This large portion of highly fine char particle that produced due to incomplete combustion is a big potential of renewable energy source. In this research, development process to benefit the local low-grade iron ore and the available solid waste as material and energy sources has been proposed. Malaysian iron ore was treated by using EFB char as reductant and heating the sample at 600�C caused a change in phase from iron oxide hydroxide to hematite phase but does not significantly improve the magnetic properties of the reduced ore. However, the presence of magnetite with the rise of temperature up to 800�C remarkably enhances the magnetic properties of iron ore as it is counted as a strong magnetic mineral. The magnetization diminishes as the ore was reduced into a partial of wustite at 900�C of reduction temperature. The magnetic susceptibility of artificial magnetite in reduced ore at 800�C approached the value of natural magnetite. The improvement of magnetic properties, particularly at 800�C of reduction temperature show that EFB char has a potential to be used as reducing agent in iron making and the reduced ore could be a promising route for the iron resource.

In recent years, environmental issues such as global warming and the energy resource depletion have become serious matters. So the steelmaking industry is strongly required to develop new technologies for further energy conservation in view of energy security. A lot of energy used for industrial processes has been wasted as heat. Waste heat recovery can be one of the key technologies to meet the requirement. Thermoelectric generator (TEG) is one of the promising technologies expected to play an important role for steel plant�fs waste heat recovery, particularly radiant heat from steel products which had not been used yet efficiently. A 10-kW class in plant grid-connected TEG system was constructed in the continuous casting line at East Japan Works (Keihin District) of JFE Steel Corporation. The performance and durability of the TEG system have been investigated under various operating conditions. This paper will describe results of the verification tests at the continuous casting line.

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