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By Jonkion M. Font

An expression for the distribution ratio of arsenic between slag and copper matte or liquid copper was developed by both, an extension of the Reddy-Blander moderl for deriving a priori the arsenic capacity, and by a relationship between the arsenic capacity and the arsenic distribution ratio. In this study, the a priori arsenic capacities in the FeO-SiO2, CaO-SiO2,MgO-SiO2, FeO-CaO-SiO2, FeO1.5-CuO0.5-MgO-SiO2, FeO-FeO1.5-CuO0.5-CaO-Mgo and FeO-FeO1.5-CuO0.5-CaO-Mgo-SiO2, slags were calculated at 1573 K. The a priori arsenic distribution ratio between the FeO-FeO1.5-CuO0.5-CaO-MgO-SiO2 slag and copper matte mn (Lx, )' and between the FeO-FeO1.5-SiO2 or FeO-FeO1.5-CuO0.5*-CaO-Mgo slag and liquid copper (Ls/cua) were calculated. The model calculated data are found to be in good agreement with the reported experimental data. The availability of reliable thermodynamic data for slag components and impurities in the slag-matte- metal system is essential for the accurate prediction of impurity capacities and distribution ratio data. The arsenic distribution ratio model developed here, can be extended for predication in multi-componet slags and mattes or liquid metal, and thereby may lead to the development of new slag systems for the efficient removal of arsenic in the copper smelting, converting and refining processes,

Jan 1, 2003

Cuspidine (3CaO?2SiO2?CaF2) is one of the most important compounds crystallized in mold flux films during casting in the continuous casting process of steel. The primary crystallization field of cuspidine has been experimentally developed in the CaO-SiOrCaF2-SiF4 system. The cuspidine-NaF binary and cuspidine-CaF2-NaF ternary systems have been also experimentally determined to study effects of addition of NaF on the primary field of cuspidine. In order to discuss its thermodynamic stability the standard Gibbs energy of formation of cuspidine has been determined by an electromotive force method using CaF2 as solid electrolyte and a transpiration method as follows: The chemical potential diagram and constituent activities for the CaO-Si02-CaF2 system have been evaluated based on the obtained thermodynamic data.

Jan 1, 2003

By Atul Kurnar

In the present research a two-cell polymer electrolyte membrane fuel cell stack (PEMFCS) with SS-316 bipolar plates has been tested. Different flow field designs were studied and a modified multi-parallel channel design is proposed. The stack is stable within ±3 mV even after 1000 hours of continuous operation, indicating efficient water management and effective removal of any metal ions from the stack. Also no iron is detected in membrane electrode assembly (MEA) by EDAX analysis after 1000 hours of cell operation. Results indicate that high operating pressures beyond 138 kPa didn't significantly increase the performance of cell, however added much to the pressurization cost of the system. Tests at different temperatures showed that at temperatures below 80°C, external humidification could be completely removed. The prototype stack is also tested under variable load conditions simulating highway-driving schedule. The experimental efficiency of PEMFCS is 48%, which is in good agreement with the model predicted efficiency of 53.8 %. Results show that 59% of the total losses are due to ohmic polarization in the cell. Further analysis on applications of the stack in automotive transportation system is in progress.

Jan 1, 2002

By Takaaki Shibata

The Tamano Refinery has developed two new processes for removing the impurities, arsenic, antimony, and bismuth from an electrolyte. The first process involves bleeding the surface electrolyte in the electro-refining cells. The copper concentration level in the outermost layer is lower than that in any of the other layers, while the impurity levels are almost the same in all layers. Bleeding the surface electrolyte increases the amount of impurities removed in the liberator by approximately 20%. The second process involves adsorbing antimony and bismuth from the electrolyte by means of chelating resin. As the electrolyte passes through the packed column of chelating resin, antimony and bismuth are selectively adsorbed. They are then desorbed by means of hydrochloric acid, and then recovered in the form of a highly concentrated antimony chloride solution by means of evaporation. This process almost doubles the capacity for removing antimony from an electrolyte.

Jan 1, 1987

By Jose Hector Figueroa P.

Mexicana de Cananea, S.A de C.V. is a major copper producer mining a large deposit of the disseminated porphyry type considered one of the largest copper resources of the world with 2.7 billion tons of 0.60% copper for the mill plus 4.1 billion tons of averaging 0.26% copper for leaching. Mining of low grade sulfide leach ore, has been an important part of the overall production of the open pit mine which started in 1944. Before this time all the mining in Cananea was by underground methods. The leaching process in Cananea began on the 1920's with in situ operations in the underground mine and small dumps up to the 1950's. Large scale leaching operations began in 1960 and the copper solutions produced were treated in precipitation plants until 1,980 when the first SX/EW Plant was put in operation in Cananea. Leaching action is essentially ferric-bacterial, with no fiesh acid added to the leaching solutions. Traditionally, 5540% copper extraction is recovered fiom ROM, 70- 120 meter high leach dumps in 80 months of leaching. Cananea has successfully improved copper recoveries by implementing several actions that include: 1. Stripping of old dumps. 2. Leaching of old dumps through slotted casing. 3. Crushing conveying leach ore to minus 8 inch and stacking it in 30 meter lifts. As result of these actions, copper recovery has been increased' to about 70% of total copper with actions 1 and 2 and up to 85% in half the time by crushing-conveying the leach ore, based on the same solubility index of the run-of-mine ore. This paper describes the above actions that were implemented to enhance the leaching recoveries from. sulfide leach dumps and the economics of such actions.

Jan 1, 1999

By Sharif Jahanshahi

Calcium ferrite slags are often associated with Professor Yazawa due to his pioneering work on the thermodynamics of this type of melts. Over the past years CSIRO has invested some effort in studying physico-chemical properties of such melts to fill in some gaps in our knowledge and explore opportunities for application of the understanding developed. These investigations cover thermodynamics, transport properties of calcium ferrite based slags, as well as the kinetics of reactions of such slags with refractories. The present paper provides an overview of some of these studies and highlights some of the interesting behavior of such melts, The oxidation state of copper and arsenic in calcium ferrite based slags are predominantly Cu+ and As3+, respectively, at oxygen potentials below 10-7 atm. The concentration of CU2+ in such slags becomes significant at oxygen potentials of greater than 10-7 atm at 1300 °C. The activities of CuO0.5 and AsO1.5 in calcium ferrite slags show strong deviations from the Raoultian Law, while that of CoO is very close to ideal behaviour with respect to pure solid CoO. Addition of SiO2 to calcium ferrite slags can have significant effects on the activities of FeO and Fe2O3 and hence the stability of magnetite phase. Transfer of oxygen in calcium ferrite slags is fast with diffusivity of 2x 103 cm2/s at 1350 °C and activation energy of 16 kcal/mol. Presence of solid phases, such as magnetite, has pronounced effect on the viscosity of calcium ferrite slags. The observed dependence on solid loading and shear rate indicates deviation from Newtonian behaviour. The interfacial tension between copper mattes and calcium ferrite slags is strongly dependent on the matte grade, with the determined values being much lower than the corresponding ones for interfacial tension between similar mattes and iron silicate slags. MgO, Cr2O3 and MgCr2O4 have low solubility in calcium ferrite slags and their solubility increases with increasing copper oxide content of the slag at 1300°C. The oxidation state of the slag has strong effects on phase transformation, dissolution rate and disintegration of refractories in calcium ferrite slags. Other key factors with major impact on slag-refractory interactions include viscosity and surface tension of slags as well as the contact angle between slag and refractory material,

Jan 1, 2003

By Ana E. Bohé, Fabiola J. Alvarez

"The separation of nickel from the aluminum present in spent catalysts and different metallic industrial residues, is proposed in the following systems: alloy Al2Ni and the mixtures 50 wt% Ni + 50 wt% Al, 10 wt% Ni + 90 wt% Al2O3 and 12 wt% NiO + 88 wt% Al2O3. The experiments were carried out in a tubular reactor with a flow of 2 l/h of gaseous chlorine and from 200 ° to 800 °C. The final products of the reaction, extracted from the hottest zones of the reactor where characterized by XRD, SEM, EDS, AA and XRF, as NiCl2 y NiCl2.6H2O while in the coldest regions AlCl3 was deposited in the first two cases and in the other there was a residue of ?, a- Al2O3, sometimes mixed with some remainder of Ni and NiO. The procedure attained different separation factors which showed the optimun conditions for the recovery of both metals. Introduction Some studies of nickel corrosion were carried out in chlorine gas at temperatures above 950ºC, and suggested that nickel is not corroded below 538ºC. [1] However, in a previous work it was shown that the chlorination allows the separation of nickel from aluminum and the formation of NiCl2 was detected from 200ºC in binary mixtures Ni-Al 50 wt%, for isothermal conditions in chlorine flux. [2] Other researchers obtained selective chlorination above 650ºC of a fly ash containing 1.4 wt% of Ni and other metals (V, Mg, Al and Fe). The Ni was separated from the Mg and NiCl2 started to vaporize at 550ºC and was after condensed in a zone of the reactor above 380ºC with 90% of purity. [3]"

Jan 1, 2008

By R. Burkhard

Recovery of metals from complex mixed wastes is a challenging task of modem material and waste management strategies. Thermal methods are an important tool in this respect. Plasma turned out to be particularly useful for treatment of complex or toxic wastes and residuals. In order to study plasma processes at reasonable costs, a pilot plasma plant has been used and wastes like ~pent Raney-Nickel catalysts, copper and ah.:lminum drosses, and. other metal containing wastes were investigated. The paper summarizes the most significant findings

Jan 1, 1995

By Jorge Alberto Soares Tenório, Flávia Paulucci Cianga Silvas, Denise Crocce Romano Espinosa, Ivo André Homrich Schneider, Erika Gusmão, Daniella Cardoso Buzzi, José Roberto de Oliveira

"This study evaluated the Salvinia sp action on metals biosorption in a synthetic sample of acid mine drainage (AMD) in order to determine the time and amount of metals uptake. Biosorptives tests were realized varying the contact time of 5, 20, 60 and 240 minutes. And keeping constant the follow parameters: pH (2.6), biomass concentration (1g.L-1), temperature (25°C) and agitation (175rpm). In order to quantify the metals concentration captured by biomass, the AMD samples will be analyzed by ICP. Biosorbent, Salvinia sp., will be characterized before and after the biosorptives tests through analysis of SEM and IR. The micrographs indicate the occurrence of micro-precipitation and changes in biomass physical structure. The infrared spectra indicate changes in functional groups present in the biomass before and after the biosorptives tests.IntroductionThe current emphasis on environmental sustainability leads the industry in general, to treat their waste. The human activities are increasing, highlighting the industrial and mining activities, and have promoted the contamination of soil, waterways and groundwater by metals (1). The waste must undergo treatment processes aimed at reducing pollution, and therefore, less aggression ecosystems.This means the importance of studies of economic and effective methods to eliminate these metals from wastewater generated. The bioindicators are good investments in this area. The aquatic weeds are plants that inhabit swamps up from truly aquatic environments. They have several morphological and physiological adaptations that enable them to colonize the various aquatic environments. They are used as bioindicators of water quality and have also been used in decontamination of aquatic environments, production of biomass for livestock feed, fertilizers, soil and fish tanks (2)."

Jan 1, 2012

By Fiseha Tesfaye, Pekka Taskinen

"Thermodynamics of the equilibrium phase assemblage Ago_9Cul.lS-Cu2-xS-CuS have been studied by an EMF -method. The ternary phase was synthesized from the pure Cu2S and Ag2S in vacuum furnace at high-temperature and mixed with appropriate compositions of Cu2S and CuS to form the cathode electrode. The EMF-measurements were made on the solid-state galvanic cell Pt(-) I Ag I RbAg,ils I Ago9Cu1.1S-Cu2-xS-CuS I Pt(+), in a temperature range from 316 K to 498K.Based on the measured EMF vs. T relations, thermodynamic functions (?fG° , ?fS and ?fH°) of stromeyerite (Ag0.9Cu1.1S) in equilibrium with Cu2-xS and CuS have been determined. The obtained experimental values have been compared with the available literature values. New experimentally determined thermodynamic properties of the solid solution (Ag,Cu)2Sss were determined.IntroductionDue to intense mining of high grade sulfide ore minerals in the past, recently, the available sulfide ores are poor in metals and becoming increasingly complex; such that, the production of high grade metals by the conventional pyrometallurgical processes is compromised. Consequently, smelters are in need to modify their operating flow sheets and strategies for processing more complex feed materials economically, while meeting the strict environmental regulations. To make the appropriate modifications, accurate thermochemical data of phases and phase assemblages which exist in these complex ore minerals are essential.Silver-bearing sulfosalts are encountered in ore minerals for the production of base metals and are common sources of silver. Among the silver-based sulfosalts, stromeyerite (Ag0_9Cu1.1S) is relatively common ore mineral in most hydrothermal vein and replacement deposits [1]. Recently, the ternary chalcogenide compound Ago0.93Cu1,07S has been studied, intensively, due to its high ionic conductivity and gradual disorder in the sequential phase transitions [2]. Therefore, accurate knowledge of the thermodynamic properties of stromeyerite has considerable fundamental and practical interest in many aspects of extractive, chemical and physical metallurgy."

Jan 1, 2014

By R. Tunold, Y. J. Zhang

"The cathodic kinetics of aluminum deposition from aluminum chloridealkali chloride melts was studied by use of electro-cnemical transient techniques at 700 °C. Aluminum deposited as an insoluble product on a glassy carbon electrode and as a partly soluble product on a tungsten electrode. The deposition was found to be a simple diffusion controlled process involving the exchange of three electrons. The diffusion coefficient of aluminum chloride was calculated - 4.sx10-s cm2 ·S-I in AlCl3 -NaCl-LiCl melts and 2.6x10-s cm2 ·S-' in AlCl3 -NaCl-KCl melts. For AlCl3 -NaCl-CsCl system the diffusion coefficient exhibited some uncertainty due to nucleation. The determined rate constant of aluminum deposition reaction was on the order of 10-' -10-2 cm'S:' Constant potential electrolysis was carried out. TiB2 was well wetted by aluminum. The species of melts penetrated into graphite and glassy carbon but not into tungsten. The diffusion coefficient of species in glassy carbon was evaluated.IntroductionAluminum chloride electrolysis is attractive for its power saving of 30%. Different process to circumvent the conventional chlorization to obtain aluminum chloride economically, such as directly chlorizating mixture of Al~03 and C in a cell with A-shaped laminated bipolar electrodes by rising chlorine (1), or by use of a composite anode (2), will promote the electrolysis technology to be realized industrially. With the appearance of the Alcoa process periodically there are studies on the kinetics of aluminum deposition. Some discrepancies seem to exist on the mechanism of aluminum deposition. Borne studies (3,4,5) showed that the deposition of aluminum was hindered by diffusion process in the melts. M.Gabco et a1. (6) claimed a preceding dissociation of a complex being the rate controlled step. This paper presents our results on the mechanism of aluminum deposition from the study by use of transient techniques and some results from constant potential electrolysis."

Jan 1, 1988

By Toshiki Kabutomori

In fuel cell powered automobiles, hydrogen is required to be stored in materials that have a hydrogen storage density of over 4 mass%; further, these materials should be capable of supplying hydrogen by using the waste heat from a fuel cell, which is at a temperature of 373 K, in order to match the mileage of gasoline-powered vehicles. A Ti-Cr-V alloy, which exhibits a BCC structure and forms a solid solution, is a promising candidate for onboard hydrogen storage materials. Although it has a large hydrogen storage capacity of over 3.9 mass%, the rechargeable hydrogen capacity is limited to approximately 2.6 mass%. In this study, the effects of fine pulverization of the alloy on PCT (hydrogen pressure-composition-isotherm) characteristics were investigated in order to improve the rechargeable hydrogen storage capacity of the alloy. From the PCT measurements of the finely pulverized samples of the alloy, a plateau in the absorption curve was observed to begin at a hydrogen concentration of 0.5 mass%; further, a rechargeable hydrogen storage capacity of 3.3 mass% was obtained. This was greater than that obtained from the sample that was not finely pulverized, i.e., 2.5 mass%. However, the plateau width in the desorption curve was 2.5 mass%, which was the same as that observed for the sample that was not finely pulverized. The increase in the rechargeable hydrogen capacity during absorption is attributed to the precipitation of the -hydride phase (MH~2) directly from the metal phase (phase). The precipitation of the phase (MH~0.5), which should be formed in low hydrogen concentrations, is suppressed as a result of a possible reduction in the internal defects such as dislocations, vacancies, and grain boundaries by fine pulverization and annealing of the alloy.

Jan 1, 2006

The cleaning of copper containing fayalite slag using a CuFe alloy was studied under an oxygen pressure ranging from 10-7 to 5 X 10-11 atm at 1200º c. The reduction of copper from fayalite slags by Cu-Fe alloys was found to be very effective. For example, at a P 02 of 10-7 atm, the copper content in the slag was reduced from 4.1 to 0.402 wt. percent after 90 min. of reaction time using a Cu- 5.27 wt. percent Fe alloy. The copper reduction rates were found to be independent of P02 in the gas phase when using Cu-Fe alloys which exhibit an iron activity of greater than 0.4. A mechanism for slag c1eaning is proposed based on the concept that the Cu-Fe alloy lowers the oxygen potential of the slag according to Eq.1 1, fol1owed by the reduction of cuprous oxide by wustite as shown in Eq.2. Here X represents element X in the alloy phase while (X) represents the element in the slag phase. The copper and iron transfer behaviour obtained in this study are explained by a ?Stepwise equilibrium model.

Jan 1, 1985

By Ali Hasham

Reduction rates of FeO in CaO-SiO2-Al2O3 slags by Fe-C melts have been investigated experimentally at 1723 K. The rates were estimated using experimentally determined CO(g) evolution rates. Flash X-ray images were employed to visualize the behavior of the melt-slag interface during the reactions. The influence of melt interface was examined by conducting two types of experiments - (i) dropping one (or several) Fe-C droplet(s) weighing 2 g into the molten slag bath, and (ii) dropping a small amount (10-30 g) of slag onto a Fe-C melt weighing 400 g. The rates from both types of experiments were compared and analyzed to determine the rate limiting steps. It was established that neither the carbon transport in the Fe-C melt, nor the transport of gas species in the gas film adjacent to Fe-C melt was responsible in limiting the reaction rate. It is possible that the slag phase mass transport may be controlling the initial reduction rate in the droplet experiments. However, a, different mechanism was responsible in limiting the reduction reaction when the overall %C in the droplets fell to about 2-3.

Jan 1, 1992

By Seetharama C. Deevi, Mohammad R. Hajaligol, Sarojini Deevi

"Carbides and nitrides of iron are being considered as magnetic materials for high-density recording due to their chemical stability and high-saturation magnetization values (> 100 emu/g). Iron carbides and iron nitrides with magnetic properties suitable for magnetic media were synthesized by employing a novel synthesis procedure based on fluidization of powders in reactive atmospheres. Fluidized-bed reactors of laboratory, bench, and pilot scale were employed for the synthesis of iron carbide, FeSC2, by reducing and carburizing U-Fe203 in the temperature range of 300 to 550 ºC. A temperature of 400· ºC and a reaction time of 2 to 3 h are found to be optimal for the synthesis of iron carbide. When the carburization was carried out in a reducing and carburizing atmosphere such as carbon monoxide, nucleation and growth of FeSC2 occurred directly from Fe304 with no intermediate phases such as FeO or Fe. Longer carburization times resulted in the deposition of carbon on the surfaces of FeSC2 particles due to Boudouard reaction, and higher temperatures favored the formation of a mixture of carbides such as FesC2 and Fe3C. Iron nitrides were synthesized by reducing u-Fe203 in the temperature range of 350 to 550 ºC, followed by nitriding in the temperature range of 350 to 550·ºC. The powders were characterized using X-ray diffraction, scanning electron microscopy, thermogravimetric analyzer, and a vibrating sample magnetometer.IntroductionRecent demand for high-quality recording of optical, electrical, and audio signals generated interest in magnetic tapes with high-recording densities as compared to the conventional magnetic tapes based on U-Fe203. At present, commercially available magnetic tapes contain maghematite, U-Fe203, as a magnetic material with a saturation magnetization of90 emu/g and a coercive force of 400 Oe. Recording of signals at a higher density per unit volume of magnetic material demands magnetic materials with high-saturation magnetization and a reasonable coercive force. Although metallic iron particles possess a saturation magnetization of 130 to 150 emu/g and a high coercive force of 1000 Oe, the gradual oxidation of iron-to-iron oxides (of lower saturation magnetization) prevents the use of iron particles for high-density recording. In contrast, iron carbides such as FesC2, Fe7C3 and iron nitrides such as Fe4N and Fe3N possess excellent magnetic properties coupled with good electrical conductivities and high hardness. The carbides and nitrides of iron have generated significant interest as magnetic materials for the next generation of magnetic tapes due to their unique magnetic properties and relatively greater oxidation resistance as compared to metallic iron particles [1-4]."

Jan 1, 1994

By Zbigniew Zurecki

The selection of atmosphere composition is critical for controlling surface quality of reactive aluminum alloys during solution treatments. An improper selection of annealing atmosphere can result in surface blistering in AI-Mg and sub-surface depletion of lithium in AI-U ingots. To determine optimum atmosphere compositions for homogenizing A1-Mg and Al-Li alloys, Ii number of exploratory experiments were carried out in air, nitrogen, and carbon dioxide based atmospheres including reactive impurities or additive such as moisture and sulfur hexafluoride. This paper describes the influence of these atmospheres on high-temperature oxidation and sub-surface defects. The results are discussed in terms of the change in Pilling-Bedworth ratio.

Jan 1, 1996

By A. Dutta, B. Devulapalli, A. Mukhopadhyay, E. W. Grald

"Computational Fluid Dynamics (CFO) has matured over the past two decades as an analysis tool for conducting virtual experiments with significant time and cost savings. It complements and reduces physical testing. CFO has penetrated the diverse materials industry in much the same way as Computer Aided Design (CAD) did more than a decade ago. As the basic numerical algorithms used in CFO have steadily improved, so have the reliability, consistency and user-friendliness improved significantly, too. Other recent trends have also contributed to the rapid growth and widespread adoption of CFO. In this presentation, CFO applications from several materials processing industries will be presented using case studies. Emphasis will be on metals, glass and semiconductor applications.IntroductionThe term materials processing covers a diverse array of industrial applications and products today. From the continuous casting of steel, to the deposition of semiconductor materials atom by atom, to the extrusion of molten polymers, materials processing applications span an incredible range of length scale, process times, pressures, temperatures and velocities. The properties of the materials themselves, in terms of density, viscosity, thermal conductivity, etc., can be complex functions of temperature, shear rate, chemical composition and time. And the processing equipment may be very complicated in geometric shape.Computational fluid dynamics (CFD), the technique of solving the governing equations of fluid motion and other related phenomena using a computer, has enjoyed widespread and rapid growth, which started in the aerospace and automotive industries. More recently, CFD has also been successfully applied to a great many materials processing problems, in spite of the challenges described in the previous paragraph. The reasons for the growing usage of CFD in materials processing are many. Using CFD to test design options and reduce the number of physical prototypes can decrease the time and cost associated with new product and process development. CFD gives insight and provides detailed predictions of operating conditions in lieu of difficult, intrusive and often expensive experimental methods. CFD can be used as an aid to scale-up processes from lab or pilot scale to full production. Troubleshooting the performance of existing equipment is often carried out with the help of CFD. Determining how an existing piece of process equipment will operate under new conditions, or with new input ,materials, is also a common task for CFD."

Jan 1, 2004

By Lenny Winkel

With the aim to develop a solar-driven process for the extraction of copper from sulfide concentrates research on the decomposition of copper sulfides under inert atmospheres has been initiated. Thermogravimetric measurements on chalcocite,(Cu2S) revealed that copper is formed already at 1823 K. Chalcopyrite (CuFeS2) also disintegrates at this temperature, although at a lower rate. Copper and iron have been identified in the solid residue. The results confirm the feasibility of copper extraction by direct decomposition of sulfides under atmospheric pressure. The decomposition under inert atmosphere prevents generation of SO2, it also alters the behavior of volatile impurities during decomposition of copper sulfide concentrates. Chemical equilibrium calculations for chalcopyrite contaminated with enargite (Cu3AsS4) have shown that the absence of an oxidic slag allows for a complete evaporation of arsenic and subsequent separation from intermediate sulfides. The need to better assess the potential of direct sulfide decomposition has prompted the development of an experimental setup for studying the decomposition reactions. The experiment has been devised such that data on the decomposition kinetics and on impurity removal can be obtained at temperatures up to 2500 K.

Jan 1, 2003

By Józef Czemecki

Polish copper concentrates are characterized by high levels of impurities, particularly Pb and As. Two technologies are being used for copper concentrate smelting at KGHM Polska Meidz S.A., namely the shaft furnace process (Legnica Copper Smelter, Glogów I Copper Smelter) and a single-stage process for direct to blister concentrate smelting in a flash furnace (Glogów II Copper Smelter). Both technologies are used at different physical and chemical conditions which results, in different impurities behavior. The paper presents flow sheets for copper production in a plant using the shaft furnace process and in another in which a single stage flash process is used. The metals distribution in particular semi-products is given as well as a method for elimination of impurities from the copper production cycle. Methods are also discussed for alloy and matte converting and copper refining to obtain low Pb and As concentrations in anode copper (0.3% Pb and 1500 ppm As maximum) that are being used in the KGHM Polska Meidz plants. Useful co-operation between the plants using different technologies, aimed at the limiting the effect of undesired impurities on the quality of blister copper produced, is also described.

Jan 1, 1998

By P .. R. Ammann

A two-stage pyrometallurgical process has been developed for the recovery of copper (and other non-ferrous metals) from copper smelter slags. All types of slags, including highly oxidized, converter-type slags, are cleaned in an electric furnace which employs mechanical mixers to promote magnetite reduction and copper extraction at high rates. In a 10-ton pilot furnace, it has been demonstrated that slags can be cleaned to 0.2-0.3 per cent copper with economically acceptable usage of raw materials and energy; copper is recovered as a high-grade matte. Pilot plant data have been scaled up to a commercial furnace and engineering designs have been made for a furnace to treat 60 tons per hour of slag from a Noranda Reactor and the associated converters. Plans are being formulated for the construction of a prototype slag cleaning furnace.

Jan 1, 1976