Preliminary List of Abstracts (Alphabetical Order)

2ND INTL. SYMP. ON ADVANCED SUSTAINABLE IRON AND STEEL MAKING

A self-correcting material balance of blast furnace model that simulates its technological and operation parameters and provides the right information about thermal state, energy requirement and displays the technical and economical parameters that are necessary for the blast furnace operation has been developed. The model has been proven useful for planning and forecasting the structure of raw materials and for evaluating the efficiency of new ores.

The steel industry has to face diverse challenges such as higher cost effectiveness, increased throughput capacities, pressure to cut fuel and reduce emissions (especially of CO2). Implementing oxygen enrichment to the burner systems of industrial reheating and forging furnaces is a perfect possibility to solve some of these challenges in an effective way. The most important issue of the usage of oxygen burners is the substantially increasing melting rate by lowering the specific production costs because of the higher combustion efficiency. Nevertheless, the change from air combusted burners to oxygen enriched heating systems is always a big step. A lot of forging and steel plants are uncertain to take. The major aim of the production is the quality of the product which should not be effected in any negative way. The implementation of oxygen in the burner system increases the heat transfer process beneficially, but also leads to a higher amount of CO2, H2O in the exhaust gas.In this work, the influence of oxygen enhanced combustion on the scale formation of steel alloys in burner fired furnaces is investigated. Therefore, experiments with various steel grades are carried out using thermogravimetric analyses and compared with investigations in real forging and reheating furnaces using oxygen enriched burners. The results imply that using oxygen enriched burners alters the kinetic model of the oxidation reaction. Under certain conditions, these changes lead to process parameters where oxy-fuel burner systems do not affect the scaling process negatively and can lead to a sustainable, energy efficient steel production. The process parameters e.g. The amount of oxygen enrichment, working temperature, furnace type and steel grades are described in this paper in details.

Steel is one of the most environment friendly products, though steel making is not. It is, however, controlled by three forces (the driving force: Technology progress; The pulling force: The economic growth and the limiting forces: The energy, environment and natural resources). The rapid growth of the world steel production has though emanated from the dramatic growth of iron making capacity. Some countries have abundant steel scrap storage, where iron to steel ratio is the lowest of the two main routes of steel making (0.70-0.65), which entails much lower carbon emissions than conventional steelmaking process involving blast furnace for iron making and basic oxygen furnace for steelmaking. Electric furnace steel making comprises multi-metallic smelting reactor and meets its metallic and energy needs primarily with scrap and electrical energy, respectively. While the lowest carbon emissions result from the use of 100 percent scrap steel in an EAF, there is a limit to the amount of scrap that can be collected and used. The paper discusses the limit to the amount of scrap that can be used and the use of duelling iron metallic viz., direct reduced iron, hot metal, hot briquetted iron in its input charge mix. The paper presents some of the essential features of energy dynamics involving metallurgical and environmental aspects of smelting of dueling iron metallic in electric furnace steelmaking with and without post combustion of reaction gases. It intends to ameliorate electrical energy dynamics of electric furnace steelmaking and its dependence on various duelling iron metallic characteristics with and without post combustion.

Rheological behavior of solid-particle and/or gas-phase containing slag is one of the most important physical and transport characteristics for understanding and optimization of steel making process, which has direct influence on kinetics of slag-metal reactions at elevated temperature. Therefore, experimental and theoretical approaches to the viscosity of solid-particle (suspension) and/or gas-phase (foam) dispersed molten slag are essential to understand complex phenomena in the steel making process, which have not been reported well so far. In the present study, the viscosity of simulated slag suspension or foam that consisted of polyethylene beads or N2 gas dispersed silicone oil was systematically investigated as functions of volume fraction and size of the secondary phase, shear rate, and viscosity of silicone oil (liquid phase) at room temperatures. It was found that both relative viscosities of the suspension and foam steeply increased with increasing the volume fractions of the dispersed secondary phase, and with decreasing the sizes of secondary phase, which finally revealed transitions from Newtonian to non-Newtonian fluid (Pseudo-plastic fluid) at certain volume fractions. In addition, empirical equations that successfully reproduced the viscosity variation of the suspension and foam was proposed by modifying the Einstein-Rosco's equation.

An expert model has been developed for BOF steelmaking process. The model includes static model and dynamic model working together. The static model is based upon various balances including heat, slag, iron and oxygen balance. The model predicts the weight and end point temperature of steel, oxygen to be blown and fluxes to be added. The dynamic model focuses on Decarburisation reaction fundamentally also as well as in association with waste gas data. This model is validated with the help of industrial shop floor data in order to use it for correct predictions. The expert model can be effectively used for simulating the process and can be used as a guiding tool to operate the process in desired manner and help to produce steel with desired end point composition and temperature.

For the purpose of high quality and low production cost of cement-bonded cold pellets, the effect of CaO addition on the Physical and Chemical properties was examined experimentally.Pellet was added with a large addition of cement /Cao mixing ratio (4-8 mass %) and lime (0-6 mass %). During the steam curing process, a half amount of CaO added changed into some calcium compound such as Ca(OH)2 and CaCO3.The reducibility Using H2 and Mixing gas (80.8%H2, 14.2% CO, 5% CO2) is higher in pellets with CaO added compared to those with no CaO addition. However, poor crushing strength values were found in pellet with CaO addition compared to those without CaO after drying at 600°C and 900°C.

Iron and steel industry is important for Ukraine's economy, standing for 40% of the country's export revenue, 27% of industrial production, and directly employing 600000 people. The current state of the iron and steel industry in Ukraine has been presented based on the data on the raw materials, iron and steelmaking industrial facilities, structure of production and export. The environmental impact of the industry has been studied, revealing the fact that it stands for 38% of industrial pollution. Some current challenges, such as insufficient energy efficiency, quality of mineral resources, obsolescence in facilities, overcapacity and export dependency have been analysed. An overview of the ongoing and planned modernization towards competitiveness on the global market has been provided.

The rationality and stability of operational inner profile is of great importance to smooth operation for blast furnace, which can be hardly measured directly. To realize online monitoring, a wireless digital measurement system for water temperature difference of cooling staves, with high precision and stability, is developed firstly. Based on the primary detecting data, three dimensional heat transfer models of cooling stave walls are built. Then, by means of the inverse problem, the thickness of brick or skull, the skull drop frequency, the hot face temperature and the distribution of peripheral gas flow in blast furnace are calculated and displayed. With the application of this model in some blast furnaces in China, rational management standards of furnace wall are built, which is beneficial for effectively controlling the furnace operation. Also, the model can reflect the change of root position of cohesive zone caused by raw materials change.

The mathematical models of the blast furnace smelting considered were: The logic-statistic balance model, the balance equilibrium model, the complex of two-dimensional models of gas dynamics, reduction, heat exchange, cohesive zone.The examples of the practical tasks solution of the blast furnace smelting, including the problem of extension of the raw materials deposits of ferrous metallurgy, in particular epy titaniferous magnetite, were given.The characteristic of ores and concentrates of the Gusevogorsky and actually Kachkanarsky deposits of the Sverdlovsk region, Kopansky and Medvedevsky deposits of the Chelyabinsk region, Kuranakhsky deposit of the Far East of Russia, Tebinbulaksky deposit of Uzbekistan, deposit of China etc. Were presented. The technological basis of processing of different ferrovanadium and ilmenite ores with receiving iron, steel, pigmentary titanium dioxide and vanadium compound were discussed.The method of evaluation on the influence of iron ore materials and coke quality on the engineering-and-economic performance of blast furnace smelting was described. The method consists in the following: Lab investigations with definition of metallurgical characteristics of iron ore materials and coke; Analytic research of the blast furnace smelting efficiency's characteristics influence by using mathematical models; Pilot and industrial testing.The single software product allowing carry out the end-to-end calculations for all range of the repartitions in ferrous metallurgy was created: Coking, agglomeration, blast furnace smelting, converter smelting, electrosmelting, rotating furnace. Technical and economic calculations allow determining the material and heat balances, chemical composition of products of any repartition, including the cost price of the finished product.The questions of the blast furnace smelting control were considered. The monitoring system of the firebrick lining deterioration of blast furnace devil was described.

A dynamic model based on effective equilibrium reaction zone approach was developed in this study to reproduce the decarburization behaviour in the Ruhrstahl Heraeus (RH) degassing process. The RH degassing process was conceptually divided into several reaction zones based on the physical description of reaction mechanisms. The volumes of the reaction zones were determined as function of RH process parameters. Calculation cycle of the dynamic model was established by developing a simplified process flow-sheet for the RH process. The flow-sheet based approach was implemented using the FactSage computational thermodynamics software package. Equilibrium files for each reaction zone in the flow-sheet were prepared using the Equilib module in FactSage. FactSage Equilib macro processing was used to perform cyclic calculations using the equilibrium files for each reaction zone. The FactSage macro was developed to take input data from and write output to an Excel spreadsheet. The calculated C profiles by the present model are in good agreement with the industrial data obtained from literature as well as shop floor data. Thus, the present model provides a useful tool to understand decarburization phenomena in the RH degassing process.

The route based on the EAF process for ironmaking production has advantages regarding the flexibility for using raw materials such as scrap, solid and liquid pig iron and DRI. The production of DRI, however, has been competitive only when the natural gas is available at a low price. An alternative to the traditional production of DRI in MIDREX type reactor is to use biomass produced gas with some improvements on the MIDREX process by using controlled oxygen to promote in situ reformation of the blast gas.This paper deals with the numerical simulation of the shaft type reactor (MIDREX) using the multiphase multicomponent approach. The model is based on the numerical solution of the fluid flow, energy and chemical species described by conservation equations. It is possible to analyze the effect of the blast gas composition and temperature on the production of DRI by using such model. Simulation results indicated that an efficient process operation can be obtained by using gas compatible with gasification technology based on biomass in the fluidized bed reactor. The result pointed out that a small amount of oxygen into the bustle gas (3% O2 and 4% CH4) can considerably improve the energy of the shaft reactor and its efficiency.

It was noticed that exploitation characteristics of finished products are highly dependent on metallic base and character of non-metallic stage (size, shape and morphology). It is possible to influence metallic base and non-metallic stage with the help of the so-called structural heritage effect; In other words, the transmission of structural features of burdening materials (first of all - input of modifiers and alloys). It is possible to influence an alloy structure, for example, by changing the melted metal cooling rate, which presents ferroalloy example. So, in order to get heat-resistant aluminum-containing cast-iron, it is highly recommended to use ferroalloy with structure, which can be provided by cooling after alloying with the maximum possible rate. Such method is used with modifiers industrial-scale production, used in powder wire for steel processing. Methods of modifier quality estimation were tried-out, including high-temperature liquid viscosimetry; Granulometric, chemical and phase modifier composition investigation; Metallographic investigation of produced metal. Recommendations are given based on exact organization.

Several sources of biomass have been used in the energy and chemical industries. The use of biomass to reduce greenhouse emissions is a promising technique due to the short recycling of carbon in the environment based on photosynthesis natural process. The partial use of elephant grass charcoal (EGC) on iron ore sintering plant is an ecological solution to reduce the consumption of fossil fuels in this process and simultaneously attain the physical and metallurgical properties of the sinter product. The advantage of elephant grass compared to another biomass source is its high productivity, high mechanization of the plantations and utilization of poor soil (degraded) with small amount of chemical fertilizer. In order to replace anthracite (ANT) by EGC, it is necessary to use a mass substitution factor (MSF) to keep thermal energy supply in the process due to its lower calorific value compared to the fossil fuel.In this experimental study, 25% of CB is replaced in the sintering process by EGC using the MSF of 1.45. The results were compared to a standard operation of 100% of fossil fuel based on the chemo-physical properties of sinter product. The results of the sinter properties obtained in this study on the pilot sinter plant for 25% of EGC were compatible with the standard operation.

Slags produced in the iron and steel industry are highly heterogeneous due to the large variation in types of steel produced, its cooling conditions and aging phenomena.The Mexican Steel industry produces more than 3 million tonnes of slags annually. Blast Furnace Slags are fully recycled, however steel slags are dumped into landfills due to the lack of information of the physical and chemical properties. This work reviews the physicochemical properties of steel slags and provides alternatives of recycling for the Mexican Steel industry.

The investigation experience of Institute of Metallurgy of Ural Division of RAS shows that in order to estimate technological melting characteristics in arc steel-melting furnaces and ladle metallurgy units, it is possible to use electric arc itself, as its burning zone is essentially a technological process zone, because several important characteristics of technological process are reflected in arc burning conditions features. The Institute of Metallurgy of Ural Division of RAS developed and tested data collecting automatic system of bath conditions, based on parameters of electric conditions, which allow: Assigning operating information about current stage of charge melting to staff of electric-arc furnace (end of basin cutting, moment of charge melting); The necessity of materials adding; Estimating the degree of deepening electrodes into slag; Estimating the metal and slag oxidity; On the base of which the staff is able to make decisions concerning interference into melting process; Changing conditions of coal inflation; Inserting slag-forming materials; Changing level of voltage, etc. The Equipment of Institute of Metallurgy of Ural Division of RAS, apart from measuring circuit, includes analog-digital converter (ADC) and computer. We receive signals of electricity and voltage from the bus-bar of the short net of every stage. The system functions independently from regularly set furnace settings.

In iron oxide and carbon composite, many reactions such as the reduction of iron oxide, gasification of carbon, and so on occur simultaneously during heating. At higher temperature, it is well known the gasification of carbon is rete-determining step due to its large endothermic reaction. The rate of indirect reduction has been studied extensively. On the other hand, there are very few reports on the quantitative analysis on the direct reduction due to analytical difficulties, while it is important to understand the total reduction mechanism in detail. Further, the reaction mechanism of the composite using carbonaceous material with volatile matter is very complicate because various kinds of reducing gases generate at lower temperature. In this study, reduction mechanism of the composite at lower temperature range was evaluated. When the reduction from Fe2O3 to Fe3O4 by solid graphite completes below 1000°C, the contribution ratio of the direct reduction in the total reduction is approximately 45%. Further, this contribution for the reduction from Fe3O4 to FeO is small. Hydrocarbon gas decomposes on iron oxide, and hydrogen gas and solid carbon generate. Decomposed carbon contributes to the reduction of iron oxide. And if decomposed temperature is high for reduction, the reduction reaction by hydrogen gas proceeds.

Paddy field in Sendai area has suffered a huge damage after the Tsunami, caused by the great earthquake on 11th March 2011. Thick sludge covered the paddy field after brine receded, and some part of this field still became uncultivable. To restore cultivation, firstly the soil must be desalted, and then many lost nutrient elements should be resupplied. For the desalting of soil, the sodium absorbed by soil particles has to be removed by the supplement of calcium, and for the growth of rice, silicate is the most important nutrient. In such circumstances, the steelmaking slag, which is suitable for the above two purposes, has been proposed as a solution for recovery. Some trials have been made to the damaged paddy field in these years to clarify the effect of steelmaking slag addition. The existence of steelmaking slag promotes the paddy growth during sprouting and maturity season. Also within those periods, the paddy grows even better than in the normal cropping condition. In addition, for the clarification on the mechanism to supply nutrient elements form steelmaking slag, experiments by column incubation methods are conducted. In this experiment, the mixture of air dried soil with slag is loaded in a PVC pipe, then irrigated with water to simulate the paddy field condition and measure the dissolution behaviour of each element. The effect of slag as a fertiliser is clarifying quantitatively with this method.

With the advent of high-Al containing steel products, significant work is being done on calcium-aluminate based fluxes for continuous casting. The new breeds of calcium-aluminate based fluxes containing B2O3 are expected to be possible alternatives to the highly reactive calcium-silicate based fluxes currently used for typical carbon steels. To provide fundamental understanding of the impact of B2O3 additions, this study focused on the effect of B2O3 on the viscosity and structure of the flux with 12wt% Na2O. Higher B2O3 concentrations in the quaternary flux system lowered the viscosity at fixed CaO/Al2O3. When increasing the CaO/Al2O3 at fixed B2O3, lower viscosity was measured. By correlating the viscosity with the as-quenched flux structure from 1773 K, spectroscopic analysis using FTIR (Fourier transformed infra-red) and Raman verified the existence of the alumino-borate structures with Al-O tetrahedral units, B-O triangular and tetrahedral units. Higher B2O3 lowered the Al-O network structures transforming the 3-D network structures into 2-D network structures by depolymerizing bridged oxygen ions (O0) to non-bridged oxygen ions (O-) resulting also in lower viscosity. Higher CaO/Al2O3 had similar effects to the addition of B2O3, where the 3-D complex network became simpler.

Nowadays, the raw sources of the Urals ferrous metallurgy are largely titanium iron ore deposits. The same deposits including ferrovanadium and ilmenite ores, deposits of Siberia and the Far East of Russia and deposits of the Uzbekistan Republic will be the most important iron, titanium and vanadium sources on the near-term and far outlook.The characteristics of ores and concentrates of the Gusevogorsky and actually Kachkanarsky deposits of the Sverdlovsk region, Kopansky and Medvedevsky deposits of the Chelyabinsk region, Kuranakhsky deposit of the Far East, Tebinbulaksky deposit of the Republic of Uzbekistan etc, are presented in the paper. The technological basis of processing of different ferrovanadium and ilmenite ores with receiving iron, steel, pigmentary titanium dioxide and vanadium compound was discussed.The method of evaluation on the influence of iron ore materials and coke quality on the engineering-and-economic performance of blast furnace smelting was described. The method consists in the following: Lab investigations with definition of metallurgical characteristics of iron ore materials and coke; Analytic research of influence the characteristics on the blast furnace smelting efficiency by using mathematical models; Pilot and industrial testing. The method is added by the predicted mathematical model for complex investigation of "hot" properties of coke, which is based on the data of initial ore quality for coking. The mathematical models of blast furnace process entered in the method are presented in the paper. These mathematical models consist of the logic-statistic balance model, balance equilibrium model, complex of two-dimensional models of gas dynamics, reduction, heat exchange, cohesive zone.The general principles of processing titanium ores and concentrates were formulated.

The single software product allowing carry out the end-to-end calculations for all ranges of the repartitions in ferrous metallurgy was created: Coking, agglomeration, blast furnace smelting, converter smelting, electrosmelting, rotating furnace. Technical and economic calculations allow determining the material and heat balances, chemical composition of products of any repartition, including the cost price of the finished product. The composition of an information system includes the following mathematical models.Forecasting model of the metallurgical characteristics of coke. Calculation of the material balance of process of coking, determination of the main metallurgical properties of coke (durability M25 and M10, reaction capacity).Model of the agglomeration of iron ore raw materials. Calculation of the heat and material balance of the process of agglomeration and pelletizing, determination of cost price of process of the agglomeration.Model of calculation of technical and economic indexes (TEP) of blast furnace smelting. On the basis of the certified basic data, the heat and material balance of melting, the temperature curves of gas and burden, the crystallization temperatures of slag, diameter of tuyeres, and the price cost of pig iron were calculated.Model of calculation of TEP of converter repartition. Calculation of a heat and material balance of melting, composition of slag, temperatures of steel (intermediate product).Model of calculation of TEP of ore thermal melting. Calculation of a heat and material balance of the melting, productivity of the furnace, consumption of the electric power, metal and slag composition.Model of calculation of TEP of the rotating furnace. Calculation of a heat and material balance of the roasting and metallization, productivity of the furnace, chemical composition of the calcine, iron ball and slag.

The steelmaking industry has been faced with significant adversity as the global economy and over-supply of products continue to saturate the market and lower profitability. These economic conditions are compounded with stronger environmental regulations of the industry with regards to process by-products such as dust, scale, sludge, and slag, which are often classified into hazardous waste increasing the manufacturing costs of steelmakers. Process by-products are formed in various sections of the steel production route from the blast furnace to the rolling operations. To lessen the impact and utilize the by-products, this study investigates the reducibility of various iron and carbon sources in the form of composite briquettes and cylindrical pellets heated using process off-gas from the electric arc furnace. Compositional variations were found to exist in the raw materials, which affected the overall reduction ability of the composite briquette. Optimal mixture of various components with binders and fluxing agents are required to enhance durability of the briquette and inhibit bursting within the hot zone of the reaction chamber. The rate and final reduction degree was dependent on the reducing agent. Results show that partial reduction of the composite briquette is possible, which can be charged directly into the EAF for final smelting reduction and production of steel.

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