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By Y. Maeda

Kosaka Smelter is a copper smelter located at the nothern part of Japan? and has been treating. complex sulfide concentrates using flash smelting technology for a long time. The flash smelting technology has an advantage in the point of controllability of matte grade and heat balance in the reaction shaft. But the disadvantage of this process, is that the dust generation ratio is high compared with other smelting process such as injection smelting technology. This reason why is that the flash smelting process is the oxidation process for the fine sulfide concentrates applying flash reaction in the oxygen enriched stream In addition of this disadvantage, the sulfide concentrates contains much volatile impurities is resulted the dust; eneration ratio more. This paper outlines the recent improvement of the flash reaction in the furnace and the behavior of impurities in Kosaka Smelter.

Jan 1, 1998

By K. H. Ho

This paper describes a simplified numerical model which is used to study the skull formation of liquid metal on a rapidly rotating disc in centrifugal atomisation. The skull formation is one of the problems limiting the wide use of centrifugal atomisation. The enlarging skull on the atomising disc reduces the yield of metal powder produced and produces a resistance to the centrifugal force which worsens the quality of the powder. It is costly and often difficult to study the flow behaviour by experiments due to the complex heat transfer and phase transformation during the processing. Computer modelling is therefore a powerful tool for mechanistic understanding of centrifugal atomisation. This paper investigates the flow pattern of the melt on the rotating disc as a function of initial temperature, melt flow rate and disc rotation speed as well as the physical properties of the melt, such as density, surface tension and viscosity using the commercial package Flow-3D. Keywords: Solidification, Rotating disk, Centrifugal Atomization

Jan 1, 2003

By Amir Rehmat

The Institute of Gas Technology has developed a fluidized-bed process for recovering direct reduced iron from blast furnace flue dust a material currently considered to be a waste from the iron and steel industry. In the process, a portion of the carbon in the flue dust is combusted to supply energy for the endothermic reaction between carbon and steam. The reaction produces reducing gases comprised of carbon monoxide and hydrogen both of which react with iron oxides to produce reduced iron. Up to 95 percent of the iron oxides contained in the waste stream can be reduced to elemental iron. The vitiated reducing gases emanating from the process can be used as fuel in the plant. The yield of iron depends upon the quantity of iron oxide present in the flue dust and generally ranges from 20 to 30 percent of the waste stream. The investment cost estimated for a single processing train dedicated to one steel plant can be recovered in less than one year.

Jan 1, 1996

By Robert F. Jenkins

This document addresses the use of practical and basic engineering principles to develop a computer model for the analysis of the various issues which affect heat transfer in aluminum sidewell furnaces. These issues include furnace charge conditions, furnace operating conditions, furnace general arrangement, furnace combustion conditions, and furnace ambient heat loss. The engineering principles applied to this model were first put to test over 20 years ago. A prototype computer model developed 12 years ago has been in continuous use by Thorpe Technologies to determine the performance of sidewell furnaces for the aluminum industry. A new computer model has enhanced capabilities for more detailed performance analysis including regenerative and oxygen enriched combustion.

Jan 1, 2000

By Yan Wen

For the impurities in the copper smelting waste acid, SO3, Cu, As, Pb, Zn, Re and other elements enter the waste acid and generate a lot of arsenic residue, gypsum and neutralized residue, in which Cu, Zn and Re metals have not been recycled. Cu, Re and As are separated by step-wise vulcanization. The valuable metals of Cu, Zn and Re are recovered by separating zinc through pH adjustment. Calcium injection is conducted for boiler for reducing the amount of SO3. The residues generated in the form of arsenate and hydroxide will be returned together with arsenic filter cake for smelting treatment so as to achieve the purpose of valuable metal recycling and solid waste reduction and harmless treatment.

By José Roberto de Oliveira

In a smelting reduction process the reduction reaction occurs predominantly in the liquid state. The main reduction agent is the carbon from the carbon saturated iron bath. The aim of the present work was to determine the velocity equation and the rate constant of the reduction rate of MnO content in a Mn0-SiO2-Fe0 slag by iron saturated carbon and the carbon dissolution rate in a Fe-Mn bath. The manganese content in the iron bath was in the range of 5 to 15 wt.%. It was observed that the rates of carbon dissolution in all Fe-Mn baths are faster than the rates of MnO reduction by the carbon saturated liquid iron.

Jan 1, 1999

By J. Y. Hwang

The relationship between coal characterization and physical cleaning has not been well understood due to the complex nature of coal. Therefore, it is difficult to apply the results of coal characterization to predict and evaluate the performance of a physical separation (e.g. flotation). Eight U.S. bituminous coals were analyzed and studied petrographically in conjunction with washability and flotation tests. The results show that grindability correlates to ash and fixed carbon contents; liberation determined directly by petrographic techniques is close to liberation determined indirectly by washability; and an ideal separation efficiency can be determined by measuring the inertinite content and the washability separation efficiency using a heavy liquid with a density of 1.4. The ideal separation efficiency was attained for most coals by packed column flotation. The ideal separation efficiency can be used for comparing process technologies and process parameters.

Jan 1, 1988

A three?stages countercurrent fluidized bed prototipe reactor to neutralize the SO2from smelter gases has been developed. For gases with 8 vol-%SO2, at 800°C and for 4 h mean reaction time of the limestone, the capture of SO2 is 99%, with off gases with 0.07 vol-%. For 2 vol-%SO2, the total capture of SO2 can be obtained at 750°C and 4 h reaction time. The calcine obtained contain a blend of unreacted limestone and calcium sulphatewith minor amounts of residual lime.

Jan 1, 2006

By Ying Li, Xuling Chen, Xiaohui Fan

"In the sintering process, the behavior and performance of iron ores is extremely complex. Different minerals have different sintering properties. In order to use iron ores rationally and effectively, multilevel fuzzy evaluation method is used to establish the comprehensive evaluation model of iron ores. Because of the relative independent characters of iron ores in sintering process, the characters can be divided into physical and chemical properties, granulation performance, and sintering properties, are divided, and together with iron ores prices as the first level index for judging, which are used as the second level index for judging. Using the analytic hierarchy process (AHP) to determine the weight of each index, which is used as the second level index. The relative membership matrix is determined by triangular membership function, the comprehensive evaluation model is established.IntroductionIn China, sintering is the main method for iron ores agglomeration. Sinter accounts for more than 80% of the blast furnace. Sinter production in the iron and steel enterprises in China plays an important role[l-2]. As the main raw material of iron ores sintering, the objectivity and integration of iron ores evaluation is essential. The iron ores evaluation methods include of metric ton price evaluation method, iron grade of a single iron ores sintering, acid-base balance method, composition assessment method and other methods which are based on the chemical composition and physical properties of iron ores to measure the quality of iron ores[3]. The high-temperature mineralization is an important process in sintering process, which affects the structure and mineral composition of the sinter, and has a close relationship with the quality of the sinter[ 4]. Therefore, in consideration of the physical and chemical properties, granulation properties, mineralization performance and sintering properties, the iron ores are evaluated by multi-level fuzzy comprehensive evaluation. The multi-level fuzzy comprehensive evaluation method makes a comprehensive evaluation, applying fuzzy transform principle and maximum membership degree principle, considering a number of factors related to the things which are evaluated. The method has lower requirements for the amount of data, and which integrates qualitative with quantitative judgment. It has a unique advantage to make up for the deficiencies of traditional evaluation methods. It also can comprehensively evaluate the iron ores in a relatively short period, reduce a lot of experiments, improve efficiency and guide the sinter production[5-6]."

Jan 1, 2013

By Dany Racine, Daniel Marceau, Denis Laroche, Dmitry Lukovnikov

Carbon base materials play a critical role in the performance of Hall-Héroult cell. The determination of their thermo-physical properties is of primary importance for modeling and designing complete cell systems. However, overcoming the associated experimental hurdles is complex and often underestimated. Of them are the Poisson’s ratio measurements and the continuous oxidation/burning of the materials at temperatures above 200°C. The novel procedure developed in this research is based on the Gleeble® 3800 system. Its vacuum chamber allows test with a chosen atmosphere at temperature of more than 1000°C. Young’s modulus, Poisson’s ratio and the coefficient of thermal expansion values can all be adequately measured using a single test. Cylindrical carbon samples (: 50mm, L: 100mm) were tested in the modified system at temperatures ranging from room to 950°C without any trace of oxidation. The resulting values were also in good agreement with literature data for a specific graphite material.

Jan 1, 2015

By M. Soltanieh

The liquidus surface? and tie-lines in the nickel-cobalt-sulphur ternary system have been determined between 1<273-1573 K. The experiments were conducted by equlibrating the liquid sulphide with the metallic alloy phase. The liquid sulphide phase was sampled and chemically analyzed. The alloy was analyzed by electrol} microprobe. Combining the present results with the.avai1abl~ literature data, the thermodynamic properties of this system were calculated.

Jan 1, 1998

By J. W. Holzenthaler

Teams continue to play a major role at the Phelps Dodge Mining Company El Paso Operations, especially during the present time of low copper prices. The El Paso Operations&apos; teams have taken the initiative during this copper market downturn and have helped reduce operating costs significantly. Because of this, Phelps Dodge El Paso Operations has continued to grow within the team process by creating a total, non- exempt salaried workforce. In the last year alone, the El Paso Operations have implemented three major initiatives to accommodate the team process. The first was the creation of "guiding principles", a policies and procedures handbook. Second was the "zero and beyond" safety initiative. Third was team compensation. In addition, the Copper Products Company has now adopted a work-team environment, following the lead of the refinery.

Jan 1, 1999

By James R. Craig

The slags generated during gasification of petroleum coke are heterogeneous and con-sist of many different phases. These phases are important because their physical properties affect the operability of gasifiers and because they concentrate many elements that are present in the petroleum coke feed in only minor to trace quantities. An understanding of the chemistry and physical nature of these slag phases is necessary to predict behavior in the gasifier and in considering the ultimate use or disposal of the materials. Slags typically consist of silicate glasses, calcium-silicates, free iron-nickel metallic phases, iron sulfides, and aluminum oxide spinels enriched in iron, chromium, and vanadium. The partitioning of elements among these phases has been analyzed and will be discussed.

Jan 1, 1989

By M. Potesser

After the primary or secondary lead production the bullion lead is remelted and charged into a vessel with following refining process. The removing of arsenic, antimony and tin takes place by salt slags or oxidizing gases like air or pure oxygen. Due to the increasing lead price, Messer Austria GmbH in cooperation with the institute of Nonferrous Metallurgy at the University of Leoben have developed a new process named OXIPOT for the refining of tin, arsenic and antimony. The OXIPOT process is in principle based on purging technology with a ceramic or steel purging device. This leads to an increased retention time of the refining products due to the deeper bath level and an optimized specific reaction volume concerning the bubble size. This paper describes the process, pilot plant, and thermodynamic calculations for the optimization concerning the selectivity of element removal.

Jan 1, 2008

A simulation of a capper concentrate smelter was built with a capacity of 450,000 tons per year. The system&apos;s components to simulate were three : a Reverbetory furnace, a Wiente &apos; s modified converter ( TMC ) and two cranes. The system was classified as dynamic, stochastic and discrete. In the simulation language choice it was concluded that the most advantageous one was GPSS/H. The model verification was done through the interactive Debugger that the language has and the statistical validation was done through the result variables of sane activities, that as a whole characterize the system (charged matte and charged concentrate to the TMC, skimming white metal and skimning slag). The validation was done comparing the simulation results of these variables with the ones obtained for those variables in a specific month in the smelter. The comparison consisted in a difference of means test and in all cases the equality was accepted with a 95% of confidence. The animation tool was PROOF, a general purpose animator, that is used after processing the simulation.

Jan 1, 1994

By Andre Thess, Jurij Kolesnikov, Christian Karcher

"During the motion of molten metal under external non-homogeneous magnetic field the induced electric currents produce Lorentz body forces in the opposite direction to the flow, causing deformation of velocity profile, vortical structures, and adding a pressure drop across the magnetic field. The same Lorentz force acts on the magnet system. We analyse these phenomena in metallurgy, namely, at molten metal pumping, stirring, continuous casting, and in contactless Lorentz force flowmeter (LFF). Experiments with liquid metal alloy, including direct measurements of Lorentz forces, velocities, and flow structure visualization were conducted. Based on this study the industrial prototypes of LFF systems were designed, built, and tested in a secondary aluminium production. A molten metal flow at high temperature (700°C-850°C) can be effectively measured. The LFF technique method allows measuring precisely the volumetric and mass flow rates linked with Lorentz force, and the mass accumulated within production process.IntroductionThe present work demonstrates the development of a non-contact electromagnetic system for measurement of a liquid metal flow. Our approach embodies the Lorentz force velocimetry [1-6] technique which is physically based on a measurement of the force acting on an external magnet system the field of which interacts with the flow. This force is exactly equal to the braking Lorentz force induced in a flowing conducting fluid. In what follows a measurement system based on the Lorentz force velocimetry principle. For monitoring and controlling the production process it is desirable to measure continuously the mean velocity of the liquid metal in order to deduce the mass-flux and volume-flux from it. The form and dimensions of the magnet system are in agreement with geometry of the operating channel. We consider here a version of magnet systems in a composition of permanent magnets.The LFF possesses a number of advantages which make it attractive for the measurement of flows in hot and aggressive melts. The relation between the measured force and the desired volumetric flow rate is often linear (for closed channel or at a constant liquid metal level in open channel). For the converting of the measured force into volumetric and mass flow rate we should know the calibration factor. The calibration factor is independent of the viscosity and density of the liquid metal and depends only on the magnetic field magnitude, the electrical conductivity of the liquid metal and the geometry of the channel in which the liquid metal flows. In aluminium production, for instance, there exists a number of standard alloy compositions having welldefined conductivities for which the calibration factors can thus be tabulated. We consider below consistently effects in liquid metals arising under influencing magnetic field, construction principle of LFF and measurements of metal flows at industrial conditions."

Jan 1, 2011

By V. V. Geikhman

The paper updates the Plant experience in the development and implementation of an advanced environmentally friendly zinc production technology complying with the technological and economic level of producers in the world and the standards of maximum permissible gas emissions stipulated by the Russian legislation. General water recycling engineering allowed to ensure 95.6% water rotation level. All solid wastes formed during treating zinc concentrate are processed into marketable products or semiproducts and sold. As a result of implementing innovation techniques production at the Chelyabinsk Zinc Plant is non-waste.

Jan 1, 2006

By Yong Hack Lee

Nonferrous smelting processes have been through a rapid transformation since the beginning of 1980. The copper smelting technology has changed from the conventional Blast Furnace process to the Flash Smelting and MIB process. In the field of lead smelting, the technology has changed from the Blast Furnace Smelting to the Direct Smelting such as QSL and KIVCET. In 1992, Onsan Refinery successfully commissioned Direct Smelting QSL technology for lead. The QSL could produce more than 160,000 ton per year of lead bullion from lead concentrate and various residues. Moreover, since the year 2000, the TSL (Top Submerged Lance) Technology utilizing the same Direct Smelting process has been successfully commissioned to treat lead concentrate as well as lead sulfate residue produced from a hydrometallurgical zinc plant. This paper presents and compares the energy flows of lead smelting processes such as a conventional process and the Direct Smelting Processes plotted on the Pb-O-S phase diagram. The oxygen potential diagram suggests how to control the oxygen potential in the fum ace. Also, it describes the recent operational experience in the TSL plant of Onsan Refinery with necessary mass balance of key elements.

Jan 1, 2003

By Sadegh Firoozi

Experiments measuring the kinetics of oxidation and making visual observations of the oxidation of approximately 6 g static lead baths containing arsenic, antimony and tin were conducted in the temperature range from 500 to 600 oC. A range of repeatable behaviours were observed, notably: the formation of a coherent, solid oxide layers on pure lead and lead-tin alloys; the formation of liquid oxide droplets during the initial oxidation of lead-arsenic and lead-antimony alloys and the eventual formation of a complete oxide layer covering the entire free surface of these alloys. Thermogravimetric measurements revealed that the rate of oxygen uptake was strongly influenced by the form of oxides being generated at the melt/gas interface. Compared to the rates of oxidation of pure lead, arsenic increased the rate of oxygen uptake throughout the temperature range via the formation of liquid oxidation products. The presence of antimony resulted in a moderate increase in the rate of oxygen uptake as compared to arsenic. Tin was effective in lowering the rate of oxidation even in the presence of arsenic because the oxidation product was always a coherent layer that acted as a physical barrier to oxygen transport to the underlying alloy.

Jan 1, 2006

By Åke Saudström

An EAF dust sample generated in a scrap based steel mill was treated by a combination of hydro- and pyrometallurgial techniques. The EAF dust contained mainly ferritic spinels forming solid solution phases according to the general chemical formula (MnxZnyFe1-x-y)Fe2O4 and other oxide phases such as ZuO. CaO and Ca2Fe2O5. The EAF dust was first treated by hydrochloric acid leaching at p8=3 which dissolved 63% of the zinc. The pyrometallurgical treatment of the leaching residue was studied using an induction heating system to simulate some important operations of EAF smelting of the residue in combination with steelmaking. The leaching residue was mixed with carbon powder to obtain a mixture with 52.1% ZnFe2O4 and 175% carbon. The mixture, scrap, and slag former were charged together in a crucible and heated to attain a melt temperature around 1650°C. The effects of different amounts of mixture on the zinc balance and iron recovery were examined. Based on the test results, suggestions are made for the EAF recycling procedure of the leaching residue.

Jan 1, 2003