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By Sergio Demetrio

Based on the current reality of the copper smelters industry, besides the advances that have been and are expected for the next few years, the authors present a futurist vision of the processing of copper concentrates and copper smelters in the years 2000. Outlined new development strategies and ways of improvement in this business, including research, development and management of the works that today posses characteristics of a profitable operation, as well as the changes expected with respect to the entry of new actors and the creation of new products The authors finally bet for small or tailor-made smelters with ad hoc technology for their raw materials and few units to coordinate -devoted to specific concentrates using high technology and low manpower. Considering the in-situ hydrometallurgical route, as well as the pyrometallurgical route in works or conversion facilities that buy or process white metal and produce copper and other metals associated with this such as gold and silver, besides sulfuric acid, plants which should be strategically located in zones with high sulfuric acid price to make this a product which contributes to the profitability of the business.

Jan 1, 1999

By Johan Sundström

Anhydrous DyC13 was prepared by dehydration of DyCl3?6H20 in a fluidized bed using both batch- wise and continuous feeding. A gas mixture with varied composition of argon and HCl was used. The productivity was high, reaching values of 0.25 mol H20/m2-st during the reaction step 6- 1 and 0.062 mol H2O/m2.s during the reaction step 1-0. The product was free from hydrolytic compounds, such as DyOCI, if control of inlet gas composition versus temperature was achieved. From the results of various experiments, some relations between HCI-concentration and temperature in order to avoid hydrolysis have been deduced. The fluidization process efficiency decreases drastically after the dehydration has proceeded down to about 10 mol% of remaining water. Therefore, in a final treatment the last traces of water were removed by slowly purging gas through a packed bed. The water content could thereby be reduced to less than 1 mol%.

Jan 1, 1997

By Donald O. Voit

A BASIC language program has been written that simulates the performance of an integrated solvent extraction circuit consisting of an extractor, a reflux fed scrubber, and a stripper. The program is designed to simulate the performance of a circuit having an aqueous feed containing each of the lanthanides as well as yttrium. The Kremser equation is used to determine the separation occuring in each section of the circuit. The required input variables are the feed composition, the separation factors, the light key extraction factors and extractor feed zone distribution coefficient, the number of stages, and the reflux ratios. The program calculates the composition of the streams at each node in the circuit, the total loading, and the remaining distribution coefficients. User interaction with the program is essential. The program has no capability to determine if the calculated values are consistent with various real restraints. Knowledge of the physical, chemical, and equilibrium behavior is essential to successfully utilize the program. The number of iterations required to achieve steady-state provides insight to the circuit response times. With suitable supervision the program can be used as a simulator for operator training.

Jan 1, 1989

By F. Guevara

The paper presents results of physical and turbulent three-dimensional numerical simulation of the gas flow in the wind box and reaction shaft of the concentrate burner of a flash furnace. Physical simulation work was carried out in a 1:5 linear scale model, where the velocity field was measured using a Pitot tube. The mathematical model consists of the three-dimensional averaged Navier-Stokes equations, turbulent kinetic energy and dissipation of turbulent kinetic energy using the Renormalization Group (RNG) theory for the k-e turbulence model. Computations were performed using FLUENT, based in a finite- volume code. The geometry of the concentrate burner was separated in two sections: wind box and reaction tower. Results obtained at the exit of the wind box were used as boundary conditions for the reaction shaft. The effect of boundary conditions on the numerical results was also studied. Results of physical and numerical simulations show an asymmetry of the velocity field at the exit of wind box. This asymmetry is possibly due to existence of a separated flow in the back of the exit ring. The agreement of physical and numerical results assess the capacity of the turbulence RNG k-e model to reproduce correctly the behaviour of the velocity field at the exit of the concentrate burner.

Jan 1, 1999

By Jonathan M. Berkoe

Design engineers and metallurgists have long recognized the need for better methods to calculate a wide range of fluid dynamic effects in smelters and hydro- metallurgical facilities. Examples can range from the capture of fume in the secondary hoods of a copper converter, to controlling the thermal effects of heat transfer resulting from metal and slag flows within a furnace. With the advent of relatively low-cost, high- speed computers and user-friendly, commercially available computerized fluid dynamic (CFD) programs, these calculations can now be made. Use of CFD increased the understanding of both hot gas and molten flows in smelter facilities and has already led to design improvements in converter fume control hoods as well as improved management of heat transfer in electric furnaces. This paper will present two representative CFD applications to metals industry facilities. To date, Bechtel has implemented CFD results on four continents.

Jan 1, 1999

By F. Kongoli

A computerized thermophysicochemical database is being developed for various processes involved in nickel smelting and converting. This database includes optimized models for slag, matte, liquid and solid alloys in the multicomponent system(s) as applied to batch and continuous nickel smelting and converting processes. This database can be used to quantify the multicomponent and multiphase slag/matte/alloy/gas equilibria, liquidus and solidus surface, tie-lines, solubility and/or losses of nickel and other components in the slag, distribution coefficients, components activities, heat and mass balance, etc. The database also includes optimized models for the viscosity of the slags associated with any of the above processes. Both databases are coupled and this constitutes a very effective method to quantify the effect of each component on several parameters of the smelting and converting processes and to diffuse the confusion that exists in the literature. Several application examples have been given to demonstrate the usefulness of this database for quantitative prediction of the thermophysicochemical properties of the phases involved in actual or developing processes, even in the areas where experiments are difficult or impossible. The considerable cost reduction that results ftom the use of this database as compared to other methods in the improvement of existing technologies or in the development of new ones is discussed along with continuing new developments of this database.

Jan 1, 2002

By Vladyslav M. Sokolov

The cost effective and environmentally friendly recycling technology was developed and tested. It enables utilization of the fine nickel-base superalloy scrap in a form of heavily oxidized scarfing granulates. The process of granulates generation was discussed in details. Their properties were investigated. The results of literature search showed anticipated sufficient improvement of the properties of cast iron by its alloying with the elements from the scarfing granulates. The novel alloying approach is based on the two stage reduction operation. Firstly thegranulates were partially reduced in a solid state by their exposure with powdery carbon at the range of 1550 ? 1700°C. Then the gotten product was efficiently introduced into liquid iron since it has a form of fine natural agglomerates for arranging the optimal conditions for reduction of the granulates. The thermodynamic evaluation demonstrates higher reduction efficiency of carbon and silicon dissolved in iron than of the same elements in a form of the separate phases. The considered process partially provides itself by energy since the reaction of reduction of the chromium oxide by silicon dissolved in liquid iron has exothermal character. The mostly complete extraction of Ni was received. The sufficient reclamation of Cr was gotten at the same time.

Jan 1, 2006

By E. S. Geskin

New material processing tools should be developed and reduced to the practice in order to meet the challenges facing the contemporary material production industry, One of such potentially important tools is supersonic liquid projectiles. It was shown that at the speed of 1500-1750 m/s the water projectile are able to demolish reinforced concrete plates, forge, to pierce and weld metals, to destroy with no explosion non dischargeable mines, etc. These projectiles are generated by simple, low cost launchers run. It is obvious that these projectiles can be applied to the ore mining and comminution. Thermodynamic considerations show feasibility of the use of these projectiles also for smelting, refining and forming. The presented paper discusses the results of the experimental study of supersonic liquid projectiles as well their potential metallurgical applications.

Jan 1, 2006

By M. Kane, O&apos

Operators and designers require a comprehensive model to predict performance of heap leach piles and provide input of reliable and defensible data for economic modelling. A conceptual, theoretical, or numerical predictive model addressing the required metallurgical, geological, biological, and operational considerations should be developed within the framework of the hydraulic performance of the heap leach pile. It is generally agreed that segregation, compaction, and consolidation are physical aspects which significantly affect recovery and in general hydraulic performance. Hydraulic performance of heap leach piles can be described through the application of unsaturated zone hydrology. Unsaturated zone hydrology describes the flow and storage of moisture and oxygen in a porous medium under conditions where the pore water pressure is less than atmospheric. The porous material is "unsaturated" if an air phase, in addition to the water phase and solid material phase, is present. These conditions describe the operation of a copper heap leach pile. This paper will focus on developing an understanding of hydraulic performance in segregated heap leach material and demonstrating that unsaturated zone hydrology can be used as the framework to improve understanding and prediction of heap leach performance.

Jan 1, 1999

By Sergei A. Degterov

A thermodynamic database for the slag, matte and liquid copper phases in the Cu-Ca-Fe-Pb-Zn-Si-O-S system has been developed for the ranges of compositions of importance to the production of copper. When used with the Gibbs energy minimization software and other databases of the F*A*C*T thermodynamic computing system, this database will permit the calculation of matte-slag-copper-gas phase equilibria that take place during copper smelting and converting. The calculations reproduce within experimental error limits all available experimental data on phase diagrams, activities of components, enthalpies of mixing, matte - alloy miscibility gap and tie-lines. The calculated solubilities of Cu in both S-free slag and slag equilibrated with matte are also in good agreement with experiment under all studied conditions, such as at SiO2 saturation, in equilibrium with Fe, Cu or Cu-Au alloys, at fixed oxygen or SO2 partial pressures and at different contents of Pb, Zn and CaO in the slag. Sulfide contents (sulfide capacities) of the slags are predicted within experimental error limits. The distribution of Pb and Zn among matte, slag, copper and gas has been calculated. The calculations are in good agreement with experimental data and predict the distributions under conditions which are difficult to study experimentally, such as at magnetite saturation or under various oxygen partial pressures and iron to silica ratios in the slag.

Jan 1, 1999

By Florian Kongoli

The liquidus surface of multicomponent slags is an important parameter in various smelting and converting processes. It helps not only to optimize the slag, chemistry of current processes and their fluxing strategies, but also to determine the availability of new slags for more advanced technologies. In a series of our previous publications, the liquidus surface of some multicomponent iron oxide slags has been quantified at several constant oxygen potentials and the effect of the latter, ignored until that moment, was quantified along with the effect of some minor components. In this work, the liquidus surface of some iron oxide slags is quantified at constant CO2/CO ratios. This is a new convenient way for the quantitative description of the slag liquidus surface and the effect of several fluxes, especially in those processes such as slag solidification, where oxygen potential changes continuously. This type of diagram also describes more dynamically the effect of oxygen potential, clarifies the relation between CO2/CO ratio and oxygen potential in terms of the liquidus surface, which is not widely understood by metallurgist today, and reduces the gap between laboratory work and industrial experience.

Jan 1, 2002

By Zviad Kovziridze

The problems related to the production and research of SiC-Si3N4 composite are presented. The technology of producing the protective casings for tips and thermocouples is developed. Optimum composition charge and technological parameters are defined. The results of casing testing at production plants are presented.

Jan 1, 2006

By Kwang-Ho Lee

The Onsan copper smelter of LS-Nikko Copper Inc. has operated the Mitsubishi continuous process along with Outokumpu process since 1997. Mitsubishi process is a bath smelting process which needs adequate melts for smelting reaction in the furnace. After a campaign shutdown it requires time to make a start melt. Onsan smelter has had much experience in flash smelting, including the improvement of the concentrate burner which is one of the most important parts in a flash smelting furnace. Based on this experience, the lances of the Mitsubishi smelting furnace were modified in order to making the starter melt with flash reaction. In 2004, the flash reaction in the Mitsubishi S-furnace was completed and was able to make the starter melt using these modified lances. Although at that time it was still under development it reduced the time required to make the initial bath-melt by about half.

Jan 1, 2006

By C. M. Acuña

At the Chuquicamata Division of Codelco-Chile high arsenic concentrates are produced, which at the smelter are processed via the Outokumpu Flash Furnace and Teniente Converters to obtain copper mattes. In the case of the Teniente Converters the production of matte grade near white metal composition is a common practice since the eighties and provided in the pyrometallurgical route no appropiate measures are taken, penalties have to be paid because of arsenic content in the anodes. During smelting huge volume of slag is produced and elimination of arsenic by slagging at this step is not economically attractive. Although during fire refining is possible to eliminate arsenic by use of mixtures of calcium and sodium carbonates this alternative is expensive, takes long process time and decreases the lifetime of the refractory lining. In spite of these facts a reasonably way to control arsenic in metal, and therefore in the anode, is taking, action in the converting step. The effects of oxygen and arsenic content in metal, arsenic in white metal and basicity index of the slag upon the distribution coefficient of arsenic between metal and slag were investigated at pilot and industrial levels. The best results are obtained for metals around 7,000 ppm oxygen and 0.3 basicity index slag, which results in a 5.7 distribution coefficient for a 5,800 - 7,100 ppm arsenic content in white metal, 18%-24% CaO slag at 1473 - 1523K. Furthermore, no significant/visible refractory wear has been realized.

Jan 1, 1999

By Alex Moyano

Due to very demanding environmental rules, and to the incrementing impurities contents in the processed concentrates, Codelco Norte smelter permanently faces new demands for planning the production program with the present fulfillment of the environmental regulation. Accordingly, the CN smelter along with IM2, developed an impurity distribution simulation model, M-DICE, which predicts the impurities behavior for each of the process units of the smelter under different process configurations and concentrates quality. The development of the M-DICE included the gathering of operational data for the process units of the CN smelter, including temperature, oxygen enriched air, matte grade, etc. Then based on a mass balance for each of the process units involved in the smelter a thermodynamic evaluation was done to derive the arsenic fractional distribution among the condensed (matte/white metal/copper/slag) and gas phases. Then, the validated M-DICE was able to predict the arsenic behavior in the Teniente converter processing complex concentrates with high arsenic content, among others. At present, M-DICE is in its last stage of development, and is expected to be a suitable environmental and process management?s tool for the Codelco-Chile?s smelters.

Jan 1, 2006

By Alex Moyano

At present, the Codelco Norte smelter processes in the Teniente Converter and the Flash smelting Furnace 1,420,000 t/y of its Chuquicamata concentrate with an arsenic content of up to 1.5%. In a near future Codelco-Chile is considering different processing options for a new projected concentrates from the Alejandro Hales mine (former Mansa Mina mine with an arsenic content of up to 6%). The main option is the possibility to process 3,000 t/d of mixing concentrates from the Alejandro Hales and the Chuquicamata mines, in the Teniente Converter. The main feature of this smelting unit will be high volatilization of arsenic when processing high arsenic-bearing concentrates. The CN smelter staff carried out a technical feasibility study to evaluate the processing of high arsenic-bearing concentrates directly in the Teniente Converter, thus the low arsenic-bearing concentrates can be processed in the FSF. Accordingly, laboratory scale tests were carried out at the Tohoku University facilities. The lab-scale results allowed an industrial scale test at the Codelco Norte smelter to smelt 2,300 tpd of high arsenic-bearing concentrates in the TC and evaluate the metallurgical impact in the smelting, converting and refining areas of the smelter. The main industrial-scale result confirmed the stabilization of the arsenic content at 0.5% in the 70% Cu produced white metal at the test condition.

Jan 1, 2006

By Pertti Pekkala

Outokumpu has 25 years of experience in the SX area. The development of the solvent extraction plants responds to an ever increasing demand for lower operational costs wd for adaptability to process disturbances with minimized risks. In this paper the features of the VSF ("Vertical Smooth Flow") SX technology are described, such as the separated pumping and mixing, the homogenous gentle mixing, the droplet coalescence and the ultra pure settling. A major advantage of the mixing technology is the high stage efficiency of above 99 per cent. The connection between this and some features of the settler front section is clarified. The present design of VSF plants is based on experience of existing operations at, for example, Zaldivar, Radomiro, Morenci, Kokkola and Harjavalta. These production plants cover a unit capacity range of 60 to 3,600 m3/h expressed as a total flow. It is evident that there are no restrictive factors to increase the total flow up to 5,000-6,000 m3/h by introducing the VSF technology. The copper SX technology has a long history reflecting many individual features of the separate copper SX plants. Still it is necessary to verify all actual running parameters by pilot tests taking into account impurities, chemicals used etc. The design of SX plants is not only about the delivery of equipment but also a process concept, and it is best tailor-made and adapted to specific local requirements.

Jan 1, 1999

By John B. Dale

A primary objective of copper mining, smelting and refining operations is the cost- effective, efficient, and environmentally-acceptable control of the level of various metal ions throughout the processing and effluent treatment flowsheets. Effective ionic control maximizes product and by-product quality, allows for broad flexibility in sourcing impurity laden ores, minimizes capital and operating costs, and can achieve zero discharge operations. In order to meet increasingly stringent cost, environmental and product quality requirements, separation technologies are needed that can selectively remove and recover deleterious or valuable ions. Ideally, the subsequently obtained salts or metals can be recycled in the process, disposed of in an environmentally acceptable manner, or sold as valuable by-products. The use of MRT, a highly selective separations technology, has been demonstrated to be a cost effective, efficient, and environmentally- sound treatment for a wide range of cations and anions that are commonly found in copper electrorefining and electrowinning circuits, as well as in environmental treatment operations. These include heavy and transition metals, precious metals, halides and alkali/alkaline earths. This paper will review a number of areas of interest including: recovery and refining of platinum group metals from copper anode slimes, recovery of copper from acid mine drainage streams, extraction of Bi, Sb and C1 from copper electrorefining and electrowinning circuits.

Jan 1, 1999

By L. H. Lewis

The relationships that link microstructural properties of advanced permanent magnet materials with magnetic properties such as the coercivity are often difficult to quantify, especially in materials with nano-scale structures. Recent work on RE2Fe14B-based powders fabricated with rapid- solidification techniques such as inert gas atomization (IGA) and melt-spinning provide insight into the nanostructural features which affect the acquisition and stability of coercivity. In all cases the coercivity is found to be a function of both the scale of the constituent microstructure and of the presence and distribution of minor phases.

Jan 1, 1997

By José Sancho, Julia Ayala, Purificación García, Begoña Fernández

"A study is carried out to see the adequacy of using flying ashes coming out from a Power Station to eliminate the copper present in waste cyanide waters that are generated in gold mines.Tests were carried out to see how effective the use of ashes taken from two Power Stations could become. Later, the tests are made using ashes coming from Narcea Power Station as this station is near the mine under study.The work is centred on looking for an economically adequate solution to close the waste decanting ponds of the mine. After several tests, a solution is reached through filtration in static layers.IntroductionThe use of coal to adsorb some water-soluble substances has been widely studied [1,2,3,4,] both in the treatment of drinking waters and in determined stages of selective detachment of cyanide gold complexes in cyanide lixiviation processes [5]. Flying ashes sent to the atmosphere by Power Stations as a sub-product of the combustion of this combustible are generally made of more of a 70 % of a vitreous aluminosilicated material and of an active residual material which may be changeable making them potentially useable as adsorbents. Nevertheless, the properties of each kind of ashes depend on the characteristics of the Power Station, of the combustibles being used, of the combustion system, etc.The aim of this work is to demonstrate the adequacy of flying ashes to eliminate the copper present in cyanide waters coming from gold mines either by adsorption or precipitation of the metal. For this study, tests are carried out with Asturian ashes which have a low quantity of lime. The results obtained in the tests demonstrate the effectivity of the method used. To be absolutely concrete, the work is carried out to establish the use of these ashes in the closing of Asturian installations of cyanide lixiviation"

Jan 1, 2008