INTERNATIONAL SYMPOSIUM ON SUSTAINABLE NON-FERROUS SMELTING IN 21ST CENTURY

Mathematical modeling of both fluidized-bed and packed bed reactors has been carried out. In the fluidized bed reactor a two-phase bubbling bed model has been used in order to estimate the interaction between gas bubbles and the dense phase in the bed. Modeling of iron oxide reduction by hydrogen in the packed and fluidized bed reactors was carried out and different behaviors of reactors were compared. The reduction behavior of solid reactants has been expressed by the grain model and computerized programs were developed in MATLAB software for solving the governing equations at conditions of different temperatures and pressures. The behavior of both type of reactors for variations in temperatures, size of the pellets and the inlet gas compositions have been studied and a comparison between the reactors has been carried out. Excellent mixing of reactants in the fluidized bed helps to minimize temperature variations and renders this system attractive for carrying out gas-solid reactions. The fluidized bed reactors show better conversion of reactants in comparison with the packed beds when solid reactants are used in the form of small pellets.

IBC Advanced Technologies’ Molecular Recognition Technology (MRT) SuperLig® products selectively and rapidly bind with target metal ions to remove them from solution. The MRT process can produce a high purity separation product of maximum added value at low cost. The process is also useful for removing impurities from metals streams. This paper provides a review of some examples of applications for MRT related to purification of specific metals processing streams including copper, cobalt, and precious metals.

This paper presents the treatment of effluents generated in the process of obtaining chitin and chitosan from crab waste. This treatment was conducted in two sequential stages: The first stage consists of an anoxic denitrifying reactor and the second stage is a nitrifying aerobic reactor packed with zeolite. In the denitrifying stage, the load rate was 1952 mgCOD/L•d and 1219 mgNO3-/L•d. Removal efficiencies were obtained as 81% of organic matter and 74% of nitrogen, while the N-protein from the influent was converted to ammonium with a production of 117mgNH4+/L•d. In the second stage, the effluent from the first reactor was fed to the nitrification phase with loads rates of 664 mgCOD/L•d and 234 mgNH4+/L•d. During this stage the ammonium was completely oxidized to nitrate producing 865mgNO3/L•d and the organic matter was removed by 27%. The overall efficiencies from the sequential steps were more than 80% for the organic matter, 74% for the N-nitrate and 100% for the N-ammonium. These results demonstrate that the effluent from the waste of the crustaceans processing industry can be treated biologically to be reused in the process.

Reliable, safe and efficient operation are critical requirements for a competitive operation of metallurgical plants in today’s market. The operation requires continuous adjustment of parameters for start-ups, shut-downs and load changes. In addition, design problems and control instability issues can result in safety hazards, significant loss of system capacity and/or emissions to the environment [1]. Dynamic simulation of a system is the representation of the time-dependent transient operation of the real system being simulated. It can be used for addressing design optimization, control stability, environmental and safety aspects that would meet these requirements. Off-gas systems often become upsetting or limiting factors in metallurgical plants. This paper illustrates how the dynamic simulation of transient processes and of their control systems can be used in “real life� situations for these purposes, presenting the general approach and examples of its application to issues related to metallurgical off-gas systems.

The cast copper elements for water cooling non-ferrous metallurgical furnaces are presented in this paper. The cooling elements fabricated by SXSG Machinery are installed in many non-ferrous metal smelters for flash smelting and flash converting furnaces, Isa furnaces, Ausmelt furnaces, and electric slag cleaning furnaces. The cooling channels are formed by submerged copper pipes and the dovetail grooves on the surface are formed in casting in one step. The cooling elements are featured by high thermal conductivity for cooling, high working pressure with no leakage risk and low water flow resistance due to seamless contact at the interface between the pipe and cast copper. The liquid copper partially melts submerged copper pipe, forming an integrated block with very high contacting ratio. The shape of the cooling elements is flexible and is easy to fit the furnace configuration, thus used as not only the flat furnace walls but also complicated components in difficult areas. With high quality, SXSG's copper cooling elements guarantee the furnaces safe and reliable performance .

Big industry production, specially in mining and metallurgy, has climbed to high volumes thanks to technical advances in automatization, chemistry and mechanical engineering, which allow the industries to operate processes that can produce hundreds and thousands of tons of product per day. These processes involve large and sophisticated equipment, and represent a high fixed cost. Optimum performance becomes an economically relevant requirement. Disruption of these processes and/or sub-optimal operation of these, even for a period of a few hours, can mean huge losses for businesses. These losses, given the high fixed costs and high production volumes justify the development of new techniques based on High Technologies for optimal management of production processes. It is the era of the technological revolution in mining and metallurgy. A team of researchers with long experience from Universidad de Chile, Universidad Técnica Federico Santa María, Pontificia Universidad Católica de Chile, and École Polytechnique of Paris, is grouped into INGMAT, to conceptualize and develop High Technology and Remote Sensing applications for mining and metallurgy industries. The scientific basis of these technologies developed by INGMAT's researchers lay in the fields of elastodynamics, electrodynamics, optics, spectroscopy, acoustics and scientific computing. Several solutions and technologies are currently conceptualized and developed by INGMAT for mining and metallurgical industry. In particular, three examples are shown: The calculation of stresses induced in rocks by mining activity (TIRAM, for its Spanish acronym), early detection of cuts in the treads of tires of mining trucks, and an airborne system for detecting objects and phenomena in the subsurface. The first one, TIRAM, is an analytical tool in the form of a software that takes mine geometries drawn using CAD techniques and computes the static induced tensions and the dynamic tensions (for simulating blasts) everywhere using novel analytical solutions for the elastic half space with compact perturbations and Dirichlet-to-Neumann operators. The second technology consists in a microwave device and an imaging technique to explore the interior of the tires of mining trucks. When small cuts appear inside the rubber and near to the internal structure of the tire it often passes unnoticed, revealing itself when the tires bursts loosing pressure. If this occurs while inside the pit, the line of trucks must be stopped and the truck with the flat tire must be unloaded with auxiliary machinery, halting the extraction process by several hours. The technology aims for detecting the cuts early during routine workshop inspections. Finally, the third technology, an Airborne Technology for the Detection and Identification of Underground Objects and Phenomena (TADI, for its Spanish acronym), consist in an airborne Ground Penetrating Radar and a novel imaging method. Its applications are wide: Geological exploration, humanitarian demining, lixiviation pile inspection and early detection of uncrushables in grinding mills among others.

1. The vector of innovative development of the Company is defined by constant perfection of industrial technologies and updating of production assets. 2. Features of mineralogical structure of primary ores.3. The approach to a choice of effective technology.4. Researches on specification of technology of enrichment for rebellious gold-bearing ores refractory to cyanation. 5. Researches on processing of concentrates of enrichment of persistent ores. a. POX options; B. BIO-OXIDATION options; C. ROASTING options;6. Technical and economic researches for the purpose of a choice of optimum processing technology of concentrates from ore.7. Recommended technology of processing of persistent ore.

Computer model of T-x-y diagram is used as an instrument to design the microstructures of heterogeneous materials [1]. Not only the trajectories of phases for the arbitrarily taken alloy in the system with many ternary compounds may be reproduced, but the material balances with the distinguishing of crystals with different prehistory are shown. Main problem in the construction of phase diagram is the appearing of the ternary compounds in subsolidus. Competition of the primary crystals A1 and the eutectic ones Ae was investigated for the quasiperitectic reaction L+A=B+R with the binary incongruently melting compound R=AmC of fixed composition. Concentration field of 4-phase reaction L+A=B+C with competition of primary A1 and eutectical Ae crystals should be divided into 3 parts with the microstructures A1+Ae+M, A1+M, Ae+M. Isopleths with the masses equivalency �1=�е, �е=�Q, �1=�Q & �ex=�Q were found, where AQ – total quantity of crystals A participated in reaction L+A=B+R, �ex – quantity of A crystals, that were exceeded and have been left after the reaction. The same investigation have been prolonged for the systems with the ternary compounds and with the peritectic reaction L+I+J=K. New information about 3-phase region with transformation was received (it may be divided into the parts: Without the phase mass increment sign changing, with 1 phase mass increment sign changing, with 2 phases mass increment sign changing, with 3 phases mass increment sign changing; In the last case all surfaces of two-phase reactions have the common directing curve).

Reduction of TiOx melts with Al and CaAlK. BorowiecRio Tinto Iron & Titanium Inc., CanadaA partial reduction of TiOx with Al was carried out to produce sinters of TiO, Ti3O2 or Ti2O by using increasing ratios of Al/Ti in the starting mixture. These sub-oxides were further de-oxidized by Ca-Al alloy. Different de-oxidation parameters for chosen Ti sub-oxides led to alloy containing of Ti or Ti3Al + Ti with dissolved oxygen level in the range of 0.20% – 0.80wt%. These alloys were separated from slag saturated in 2CaO×Al2O3. The reduction of TiOx melts with Al at 1750oC led to poor phase separation and excessive contamination of Ti aluminide with dissolved oxygen and secondary Al2O3 inclusions. A significant improvement in the phase separation and a level of dissolved oxygen in Ti aluminide was achieved by fluxing of TiOx melt with CaO or CaO/CaF2 prior to or after reduction. This way, the level of dissolved oxygen in the solidified Ti-aluminides dropped to 1-2% range. Preliminary tests were carried out on de-oxidation of these alloys with Ca-Al alloy.

Platinum Group Metals (PGM), which have high melting temperatures and high chemical durability, are being widely used as electronic materials, catalyst, etc. It is important to develop their recycling processes in order to utilize the urban mine in our sustainable society. In high temperature extractive processes with slag treatment, however, some elements are missing probably due to oxidation. In our research group, the mechanism of PGM dissolution into slags has been investigated to clarify suitable conditions for the recycling process. Solubilities of PGMs, such as Pt, Rh and Ru, into various composition of slags were measured together with their temperature dependency. By reviewing the results, dissolution mechanism of each element will be discussed in the present paper.

The solubility of indium in molten CaO-SiO2-Al2O3 system was measured at 1773 K in order to establish the dissolution mechanism of indium under highly reducing atmosphere. The solubility of indium increases with increasing oxygen potential, whereas it decreases with increasing the activity of basic oxide. The relationship between the indium capacity and sulfide capacity shows a good correlation in consistent with the theoretical expectation. The enthalpy change of indium dissolution reaction is negative, indicating that the dissolution is an exothermic reaction. The heat of dissolution into the high silica melts is greater than that into the low silica melts. The solubility of indium is strongly dependent on the content of silica. The activity coefficient, and thus the excess free energy of In2O linearly decreases with increasing silica content, indicating that the In2O is believed to behave as a weak basic oxide in the present CaO-SiO2-Al2O3 ternary system under reducing conditions.

The dissolution of chromite from Bushveld Complex of South Africa in liquid slags was studied experimentally. The slag compositions chosen were representative of the ferrochromium production and stainless steel making. The dissolution process was monitored by chemical analysis of the samples taken from the melt at predetermined time intervals and SEM-EDAX analysis of reacted chromite cylinders. Experimental procedure involved the use of rotating cylinder technique in an inductively heated quartz reaction tube under the flow of argon gas in the temperature range 1550 to 1665 degrees centigrade. Empirical relations between the slag composition and the dissolution of chromite and the effect of different degrees of reducing conditions were established by using a statistical model. With this, a large amount of information in regard to the effect of slag composition on the dissolution of chromite was made available over a large range of slag compositions for practical applications. The empirical relations have shown that the chromite dissolution in silica-alumina-calcium oxide-magnesium oxide slag system increased with increasing alumina, increasing basicity, decreasing silica and decreasing oxygen partial pressure in the system. The dissolution of chromite also increased with increasing rotational speeds indicating the possibility of diffusion control of the process. SEM-EDAX studies on the reacted chromite cylinders showed that coring took place within the chromite grains subjected to dissolution reactions for a sufficient length of time. Chromium and iron concentrations in the chromite phase were decreasing when moving from the centre toward the surface of the grains where else aluminium and magnesium concentrations were increasing in the same direction indicating the opposite diffusion of these species. The slag also penetrated into the chromite grains increasing the silica content of the grains together with alumina and magnesium oxide.

The study of fundamentals transformations of different copper concentrates blends under flash combustion were studied at laboratory scale using a "drop tube" set up. The effect of particle sizes and mineralogical composition of copper concentrates were evaluated in order to analyze those effects in the quality of the combustion where the ignition temperature, the sulfur removal and the Fe3O4 formation were used as quantifiable parameters for the characterization. Six types of concentrates with values of S/Cu from 0.957 to 1.424 were used. Different binary blends were tested as well of blend of different sizes fractions from two types of concentrates (ie the fine fraction of concentrate a, with the coarse fraction of concentrate b). Mineralogical analyses of synthetic phases obtained by quenching were performed using QEMSCAN®. The results were interpretated by using the group combustion theory.

Energy is consumed at all stages in the production of metals – mining, beneficiation and chemical extraction – both directly in the processes and indirectly through the production of inputs (such as electricity and reagents) used in the processes. The sum of the direct and indirect energies of the individual stages along the value chain is the embodied energy of the commodity. It is used for comparing the energy intensiveness of commodities. ¬The embodied energy of the common metals varies widely, from typically around 20 MJ per kilogram for lead and steel to over 200 MJ per kilogram for aluminium, with the chemical transformation stages (leaching, smelting, electrowinning, etc) contributing the largest component and mining the least. Factors affecting the embodied energy include the stability of the minerals, the ore grade and the degree of beneficiation (particularly grinding) required. The quantity of greenhouse gases produced frequently follows closely the trends in embodied energy though for those metals which require a high component of electrical energy, such as aluminium, the source of electrical energy (coal, hydro, nuclear, etc) has a major impact on the quantities of greenhouse gases produced. Globally, of all the metals, steel production contributes the greatest quantity of greenhouse gases (about 7% of global CO2 produced from fossil fuels) since, although it has a low embodied energy content it is produced in huge quantities (about one billion tonnes per year) . Aluminium production produces around 3% of global CO2. The energy required to recycle metals is a relatively small fraction of the energy required to produce metals from their ores since energy is required largely only for melting and not chemical transformation. However, when the energy required for collection and separation of scrap is included, the embodied energy of recycled metals increases as the fraction of scrap collected increases since transportation and separation costs progressively increase. Technology plays an important role in reducing the embodied energy content of metals and greenhouse gas production and there has been progressive improvement over many decades. However, without step changes in technology incremental improvements in energy efficiency become harder and harder to achieve.

The present report deals with an alternative way of producing pure metals by their reduction from the respective oxides. In contrast to the conventional methods of metallurgical treatment of ores the production of pure metals is realized using the methods of thermal dissociation of oxides in the atmosphere of ultra-low oxidation potential. The formation of such an environment is possible by using an oxygen pump. The process can be simplified and accelerated by suppression of the oxygen partial pressure in the useful capacity as a result of interaction of alcohol vapor with oxygen. For example, the introduction of 0.2 mg of alcohol in the atmosphere of 1 l-capacity closed air container and its heating to 800oC provides obtaining nitrogen with the oxygen partial pressure of 10-22atm. Increase of the temperature up to 1500oC causes ultra-deep evacuation of oxygen to 1028atm. Such conditions promote dissociation of oxides of almost any kind. A positive aspect is that the thermodynamic equilibrium of partial pressure at a given temperature is set during few seconds. An installation for ultra-deep oxygen evacuation has been constructed and a methodology for conducting experiments was developed. The paper presents the results of complete thermodynamic analysis of the ethanol reduction processes of oxides (CuO, NiO, CoO, Fe2O3 and Cr2O3) in the temperature range 300-1500K.

Fayalite based slag has already been used for a long time in copper metallurgy. The production of copper from both ores and secondary resources results in major amounts of fayalite slag at a rate of 2.2 ton slag per ton of produced copper. Fayalite slag still contains valuable metals in concentrations sometimes exceeding the content of current natural ores. Rather than being a waste, the slag residue itself can be used in different applications. In order to utilize fayalite based slag and improve the sustainability of the copper metallurgical process, new extraction techniques and slag applications need to be implemented or developed. Although fayalite is the main phase, the resulting microstructure and metals content of the slag slightly differs depending on the metallurgical process and the cooling practise. Applicable techniques for metal recovery and slag utilization depend on the final microstructure of the slag. This paper reviews existing and novel routes for metal recovery and fayalite slag utilization. Firstly, an estimate of the amounts of old and currently produced fayalite slags together with differences in microstructure is given. Secondly, existing and novel techniques to recover metals from fayalite slag are discussed. Thirdly, the utilization of fayalite slag in for example construction applications is described in relation to leaching of metals. Future prospects for fayalite slag research will be indicated for recovery of the remaining metals and utilization of the slag or residues subsequent to metal recovery.

A feed-forward control, optimization and automation technique was developed in order to properly control and improve the converter products quality, increase the production rates, minimise chemical and mechanical copper losses in the skimmed slag, minimize the amount of silica as a flux, minimize/optimize the blowing time, decrease the overall cost, increase the life or refractories and assure a consistent operation. The technique was validated with the industrial data and special analysis and successfully applied in everyday converter practice. The advantages resulted from this work are also summarized.

Kumera Steam Dryer has been the predominant drying equipment for non-ferrous metal concentrates for new dryer projects of last decade. There has been a continuous need to accommodate to a wide variety of material characteristics such as moisture, grain/granulate size, abrasion wear, corrosion, ignition, mineralogy etc. Feeding of wet and sticky materials to the dryers is the first issue to be clarified. A specially designed Kumera Feeder was recently proven to be adequate to the materials of such nature. Some processes, like direct to blister copper, require very fine and homogenous feed material. In such cases the Kumera Steam Dryers can be integrated with a multi-layer screen to the rotating drum, which not only controls the particle size to the smelting furnace as needed by the process but also makes an easy set-up of the connected equipment in a limited plant area. This applies also for fractioning of materials either having a wide particle size distribution or being prone to pelletizing in the dryer. Abrasive wear of the pipe elements has been found in some dryers due to the free flow of dried concentrates and foreign objects. Chemical corrosion on the pipe elements by wet concentrates and other wet feed materials, like precipitates which has high halide content, can be a critical factor affecting the maintenance costs of the steam dryer. There are also other challenges, such as the risk of ignition when the dryers deal with thermally sensitive materials, like the hydro-metallurgical residues in which the elemental sulfur content is possibly high. These factors together with many others have been taken into consideration from the beginning of the engineering, allowing Kumera Steam Dryer a long lasting, cost-efficient and safe operation.

Oxidizing roasting is a unit operation used in the metallurgical industry to convert metal sulfides into oxides, sulfates or oxy-sulfates. In the hydrometallurgical routes to obtain the metals, the oxides and sulfates are easily dissolved in solutions but the sulfides are very difficult to dissolve. The sulfide concentrates are usually roasted in industrial reactors using air at temperatures varying from 600 to 1000°C. A commonly used reactor is the fluidized bed reactor, which presents a simple design, good thermal recovery, easy temperature control and high conversion when compared to other rectors. In an industrial plant in Brazil, zinc sulfide concentrates are roasted in a fluidized bed reactor at temperatures around 950°C in the presence of air. According to thermodynamic studies, the use of temperatures above 950°C would improve the sulfide to oxide conversion. However, the concentrates also contain iron, lead and copper sulfides among others. The presence of these compounds leads to some reactions that form low melting point phases causing agglomeration and sintering of the particles in the bed, thus restricting the operating temperature. Another way of improving the conversion is to use air enriched with oxygen. This work presents a detailed study of the fluid dynamics of the roasting reaction of zinc sulfide concentrates at 950oC. The data were collected from experiments carried out in an industrial fluidized bed reactor. The theoretical and experimental characterization was performed using the operating variables of the industrial reactor. Fluid dynamics diagrams (Geldart, Schytill and Grace) were drawn for the industrial practice at certain conditions. From the analysis of these diagrams, it is suggested that superficial gas velocities in the range 0.2 - 0.6 m/s should be used.

Hafnium metal is produced industrially by electrolysis of tetrachloride dissolved in molten equimolar mixture of sodium and potassium chlorides, to which some sodium fluoride was added, or by the ingenious process developed by Kroll for producing zirconium and titanium. In the latter case separation of hafnium formed from the excess magnesium and by-product magnesium chloride is achieved by vacuum distillation resulting in the formation of hafnium sponge. To obtain compact hafnium metal the sponge produced must undergo sintering at elevated temperatures under vacuum. Until now there was no information concerning sintering conditions and a mechanism of the process. In the present study we attempted to investigate mechanism of the mass transport through studying the kinetics of sintering of hafnium sponge. Two different techniques were employed to determine the mechanisms of sintering: Activation energy measurements using dilatometry and subsequent analysis of sintered hafnium structure by scanning electron microscopy. The experiments on hafnium sponge sintering were conducted between 1000 and 1500°C in high vacuum (residual pressure less than 0.1 Pa). It was found, that hafnium sponge sintering begins at 1100°C. Increasing temperature to 1300°C leads to enlargement of grains through their agglomeration. Samples obtained at 1400 and 1500°C represent a compact metal with small pores in the volume. During sintering the samples shrink equally in axial and radial directions. Depending on the process temperature the samples of different densities were obtained. Hafnium sponge sintering rates were calculated for different temperatures on the basis of the results of dilatometry measurements. The Arrhenius plot of sintering rate represents a superposition of two straight lines. Using calculated apparent activation energies (350±70 kJ/mol for 1100-1400°C and 47±2 kJ/mol for 1400-1500°C) and data concerning β-titanium sintering we conclude, that the diffusion of metal atoms in the crystal lattice (or lattice self-diffusion) is the liming stage of the process at 1100-1400°C, while at higher temperatures, 1400-1500°C, the sintering process is controlled by grain boundary self-diffusion.

The present paper focuses on the characterization and leaching of pelletized SiMn SAFD (silicomanganese submerged arc furnace dust). Characterization of the examined submerged arc furnace dust was carried out by X-ray fluorescence analysis (XRF), X-ray diffraction (XRD) and scanning electron microscopy (SEM). A number of phases were identified, including metallic manganese, jacobsite, braunite, diopside and quartz. Leaching experiments were based on the extraction of Mn from SAFD with dilute sulphuric acid at atmospheric pressure. The influence of reaction temperature was studied and up to 49 percent Mn extraction was achieved. XRD and XRF were used for the characterization of the leached residues. This showed that the major phases present were braunite or bixbyite and gypsum.

The anode furnace is the final vessel used for the pyrometallurgical production of copper, whereby anode grade copper is produced by fire refining the metal. Subsequently, high quality anodes are cast in open moulds on large revolving casting wheels. Typically, the copper is poured via a taphole into a launder system by rotating the furnace into an appropriate position. Control of the casting rate is also performed in this manner. However, this procedure has many disadvantages including splashing, oxygen pick-up, and energy losses. This paper introduces an innovative solution to open and close the taphole with a slide gate system. Two plates with defined drilled holes are slid against each other, which enables effective starting and stopping of the copper flow as well as throttling. The complete system is described in detail, including the mechanical components for accurate movement and secure fastening of the plates as well as the refractory parts like the nozzles, well blocks, and plates themselves. Since all these refractory parts are in direct contact with molten copper, they have been especially developed to withstand severe mechanical and thermal stresses, and chemical attack.

In this paper through a lot of comparison of test it is found for mechanical vibration added in liquid copper its solidification structure is changed from large grains to fine grains with equiaxed crystals by means of optical metallographic, under different processing conditions such as vibration frequency, amplitude, casting temperatures as well as the types of vibration. With the increasing vibration frequency, columnar crystals become thinner; Equiaxed grains increase, although its size is still large. It is analyzed that there is an optimal vibration frequency for fine grains. At an appropriate frequency, mechanical vibration can improve the solidified structure of metals obviously by increasing amplitude. Horizontal and vertical vibrations are similar impacting on solidified structure of pure copper. The lower casting temperature is good for the formation of fine equiaxed grains with the vibration applied. There are several mechanisms of mechanical vibration treatment on solidification structure, which is also discussed in this paper.

Chemical degradation of a refractory lining is most commonly considered as a dissolution process whereby the refractory components dissolve into the liquid slag. Hence, the lining thickness is steadily reduced. The dissolution process is not merely limited to the slag-refractory contact surface, but due to capillary forces, also occurs inside the porous refractory brick. This paper describes how the interaction between slag and brick during infiltration, changes the slag composition as a function of infiltration depth. Knowledge about the selective filtering of certain slag components by a refractory brick is indispensible in predicting the chemical degradation, especially when significant changes in slag composition are present. In this case, often seen with non-ferrous slags, the situation in the interior of the brick cannot be adequately predicted based on the global slag and brick composition. To study this “filter effect�, a magnesia-chrome finger in contact with a PbO-SiO2-ZnO-Al2O3-CaO liquid slag at constant temperature is tested. Using SEM-EDS analyses the slag composition as a function of infiltration depth is measured. Based on the microstructure at different positions, the interactions leading to modified slag compositions are determined. They can be classified into two categories: (1) slag components that diffuse into the brick phases and (2) reaction between slag components and dissolved brick components forming new solid phases. Slow diffusion prevents the slag from reaching its equilibrium concentration before it infiltrates further in the brick. The slag composition, therefore, not merely depends on the occurring reactions but also on the relative diffusion rate in the refractory phases (compared to the slag infiltration rate).

More intense furnace operations require effective cooling in order to achieve low refractory wear and good furnace lifetimes, making cooling technology is an important aspect of furnace opera-tions. Optimum cooling solutions are required for the most critical furnace regions. However, the use of water - today’s standard cooling medium - has some disadvantages, as it can cause prob-lems both during furnace start up and operation, namely hydration problems, corrosion, and ex-plosions. With METTOP’s new patented cooling technology it is possible to overcome the disadvantages of water by using an alternative cooling medium, namely ionic liquids (ILs). The big advantage of ILs is the fact that they can be used at higher temperatures than water (hence avoiding hydration and corrosion) and do not lead to explosions when contacting molten copper. This results in prolonged refractory life and hence furnace campaigns, as well as improved work safety. Different ILs were tested thoroughly regarding contact with liquid copper, corrosion, and heat transfer. Furthermore CFD calculations were made to investigate and the heat transfer. These were verified by experiments in a test stand. The good results of the tests lead to the design of first industrial cooling solutions. Due to the special properties of ILs, they are not only a substitute for water cooling but can also be used in applications where water cooling would be too danger-ous, and hence provide a wide range of possible applications in metallurgical furnaces.

The use of anomalous X-ray scattering (AXS) at energies near the absorption edge of elements enables us to provide answers for various questions by making available accurate partial functions for individual pairs of constituents or the environmental structural functions around a specific element in multi-component materials. The AXS method works well for systems containing next neighbor elements in the periodic table, such as the distribution of cobalt in ferrite spinels or in amorphous ferrite glass. The present talk will demonstrate the usefulness and validity of the AXS method with some examples of aqueous solutions and thin films. The AXS method coupled with reverse Monte Carlo (RMC) simulation is also quite useful for providing the middle range (a few nm) ordering structure in both crystalline and non-crystalline states. This novel method provides a quantitative tool for describing imperfections in materials with complicated structure using polyhedral units. The usefulness of this method will also be presented by the results of corrosion products formed on the steel surface.

Mathematical modelling of a continuous fluidized-bed reactor has been carried out for non-catalytic gas–solid reactions. The two-phase bubblingbed model has been used. The feed stream size distribution with reversible or irreversible first-order kinetics can be considered by the model. The Grain model was used for non-catalytic reduction of solid reactants. A program was developed in MATLAB software for solving the governing equations at conditions of differenttemperatures and pressures. The model was validated using experimental data and simulation results available in the literature for the iron orereduction with a gas mixture containing hydrogen and was also used for predicting the extent of reaction for reduction of cobalt oxide by methane.

Lead is an engineering material used mainly in the manufacturing of lead-acid batteries for the automotive industry. Lead is a non-ferrous metal susceptible to recycling due to its high corrosion resistance. Lead recovery from exhausted batteries is carried out by the pyrometallurgical route. This work is focused in the copper drossing process. Lead refining process is carried out industrially with the addition of the reagents (S) on the liquid surface and further stirring of the bath with a propeller; This procedure is very inefficient and afterward it was optimized by injecting the powder reagent through a lance into the lead bath, therefore the chemical reactions and the kinetics of the process were optimized. In this work a mathematical simulation was carried out on the copper drossing process with the software COMSOL 3.4. An hydrodynamic study of the injection process of the lance-kettle system was carried out. A velocity profile was obtained according with the injection rate of the particles. The residence and mixing times of the process were obtained, the best conditions for the copper drossing process is injection rate of 3.31 m/s at 380°C. The kinetics for the copper drossing was mathematically simulated with the determination of the copper concentration profiles. The modeling results were validated with experimental results obtaining good agreement.

The reduction of Indian chalcopyrite concentrates from Ghatshila mines with carbon was studied in the presence of lime in the temperature range of 1123K to 1573K. An attempt was made to determine the oxygen potential corresponding to the selective separation of two metals, copper and iron, during the reduction of chalcopyrite by carrying out emf measurements under isochronal heating rate conditions using an yttria-stabilised solid electrolyte cell with Cu/Cu2O as the reference electrode. The isochronal rate data for oxygen potential measurements were analysed by comparing them with the data from isothermal kinetics studies on the reduction of natural and synthetic chalcopyrite minerals in the above temperature range. The analyses of phases formed were carried out using the X-ray powder diffraction and scanning electron microscopic techniques, which showed the presence of a new quinary solid solution CIII phase. The solid solution phase, CIII forms as a result of mixing between the two rhombohedral lattices: High-temperature form of Cu2S and CII (FeO. CaS) compounds. The mechanism of reduction of chalcopyrite with carbon in the presence of lime is illustrated by the explanation of the role of the intermediate phases, CII, CIII and matte phases.

Copper fire refining consists of two stages: I) oxidation, desulphurization and slagging of impurities, and ii) reduction of an oxidized copper. Couter-current flow of a blister copper and oxygen containing gas through a reactor, filled with ceramic grains, leads to very fast copper oxidation. Gravitational, continuous flow of an oxidized copper through a packed bed of charcoal or low sulphur coke in a second reactor results in very effective and rapid copper reduction. Process principles and mechanisms have been analyzed in details. Modeling of the process allowed for the explanation of the very high kinetics of copper oxidation and reduction, showed by the results of the laboratory and pilot-industrial scale tests.

Platinum metals are used in various areas of the industry preferred as catalyst. Traditional the quote of recycling is very high and the primary production is in the same scale than the as secondary production. With view of the constantly rising platinum return flows the cost structure of the secondary production becomes more relevant. The platinum containing ores are separated by grinding and flotation from the pace, even if the production of other metals is the preliminary goal. The platinum metals remain with the electrolytic refining of the by products, mostly in the anode sludge or in chemical procedures they build an insoluble residue. For the production of the individual platinum metals in general concentrates of 70-90 % are used. The concentrates are subjected to a dissolving process and the individual metals are separated first roughly and refined afterwards on the commercial purity. The platinum metal is transferred by special oxidation and reduction steps into soluble salt, that crystallizes and can be filtered off. After the first precipitation the platinum salt is not yet purely enough and special cleaning steps are always submitted. In the case of platinum sal ammoniac the salt is calcined at 800°C developing a platinum sponge. The platinum sponge is solved again. This time consuming cycle is passed through, until the platinum has the necessary purity. The main goal of the process development done by InVerTec was to reduce the process time during the calcining step and during solving the platinum by implementing microwaves with 2.45 GHz as energy source. In the paper a comparison of the conventional and micowave process is discussed. A main topic is the influence of the MW-power control (power level, pulse length, local plasma ignition) on the platinum sponge morphology. In the second part of the paper the re-dissolving process of the platinum sponge in a chorine saturated hydrochloric acid is discussed. To achieve high solving rates the temperature of the platinum has to be as high as possibly. On the other hand the solubility the chorine in the hydrochoric acid has to be as high as possible to increase the platinum conversion. But with increasing temperature of the hydrochoric acid the solubility of the chorine strongly decreases. This conflictive behavior can be overcome by microwave heating the suspension. Especially if high power MW-pulses are used the MW-heated solving process is much more effective than the conventional heated process.

Arsenic content in sulfide copper concentrates from Andes region has been continuously increased during the last decades. This situation places copper smelters in a challenge to control minor elements in order to avoid any pollutant emission. We analyze options for this control by some classical pyrometallurgical operations and some other new proposals of processes coming from R&D programs undertaken by the Chemical Metallurgy Processes Group at the University of Concepción during the last 20 year. We present in this paper the analysis of three new proposals starting from their fundamental physical chemistry conceptualization up to the pilot plant tests.

Novel Electrochemical Sensor for the Determination of Hydrogen in Aluminium– From the Laboratory to the Shop Floor –C. Schwandt, M. P. Hills, R. V. Kumar, D. J. FrayDepartment of Materials Science and Metallurgy, University of Cambridge, Cambridge, CB2 3QZ, United KingdomThe quantitative determination of the hydrogen concentration in gases, liquids and solids is a subject of huge scientific and technological interest. One application of particular relevance is in molten aluminium processing, where the hydrogen content needs to be monitored and controlled to ensure high-quality pore-free casts. Electrochemical sensors based on proton conducting solid electrolytes are ideally suited for this purpose, but their use in aluminium melts has thus far been hampered by insufficient materials performance as well as awkward probe design and operation. This presentation summarises the research and development work at the University of Cambridge in the field of solid state proton conductors that has led to the development of a novel, and now commercialised, electrochemical sensor for the quantitative determination of dissolved hydrogen in liquid aluminium and aluminium alloys. Topics addressed encompass the design and assembly of the sensor, as well as the selection of materials for the individual components, including the ceramic electrolyte, the metal-based hydrogen reference, and the glass seal of the reference. Also discussed are the validation of the sensor in the laboratory and its performance in field trials.

In this study, the fluid flow behaviour of a copper slag-matte in an industrial Peirce- Smith converter was simulated numerically in 2-D and 3-D by use of volume of fluid and realisable k-ε turbulence model. These models could satisfactorily account for the multiphase and turbulent flow and were implemented using commercial computational fluid dynamics numerical code, viz. FLUENT. Moreover, a cold model was constructed for physical simulations by use of a Perspex container with seven tuyeres on one side of the cylinder representative of the Peirce Smith converter. Compressed air was blown into the cylinder through the tuyeres to simulate oxygen enriched air injection into the vessel. Industrial feed, product and by-product referred to as matte-white metal and slag were simulated with water and kerosene respectively. The influence of blowing conditions on the distribution of phases was studied with compressed air flow at constant simulated matte and slag ratios. Both numerical and experimental simulations were able to predict the dispersion characteristics of the system in relation to flow and have led to significant insights into the fluid dynamics of Peirce-Smith converters.

This work displays how apply the process analysis methodology to optimally design a powder-manufacturing prototype. The study is applied to making Sn powders what are used to making solder electrodes. The objective of this study is to know and evaluate the effects of major process variables, as gas pressure pipeline, gas volumetric flow rate and molten metal superheat, on mean particle size, an important parameter which is representative of any pulverized system. An analytical-empirical mathematical model was developed and programmed to predict mean droplet-particle size and both thermal and dynamics behaviors of particles, it was with the purpose to determine the optimal dimensions of atomizer tower, and thus saving materials and safe the product. The mathematical algorithm was compiled in TURBO PASCAL 7.0 and graphical results for both thermal and dynamics parameter variations were obtained. Ranges for process variables were established according to capacities of both gas and molten supplies. Once built the atomizer tower, an experimental design was developed and carried out; Its results were compared against obtained in the simulation. Analytical and experimental results were good agreement, so the mathematical algorithm is able to simulate the atomization powder into the ranges of this study and allow the prototype optimizing to making determined product features.

Newco Ferronikeli of Drenas was privatised in year 2006, production process has started in year 2007 with first technological line, while second technological line in year 2008 and is operating very successfully till now. During continuously efforts of improvements in metallurgical process of obtaining Fe-Ni was achieved to be recycled converter slag and eliminated at all adding of limstone in charge of Rotary Kiln. The positives effects which have been achieved in calcinations process of Rotary Kiln are: Reducing of consumption of mazut, reducing of sticking of calcine in calcinations area, increasing of temperature of rousted material, increasing of recovery of Ni, increasing of pre-reduction of rousted material and increasing of capacity of Rotary Kiln. Into Electric furnace was produced a slag with lower acidity and lower smelting point and better cast ability, improving smelting process of production Fe – Ni as well. Except improvement to the metallurgical process of obtaining Fe-Ni, has been decreased the pollution of environment as well, producing less CO2 in rotary kilns and electro-reduction furnaces.

Experimental studies on the phase equilibrium and the liquidus isotherms for the CaO-SiO2-PbO-ZnO-FeO-Fe2O3 system with CaO/SiO2 mass ratio from 1.0 to 1.6 and Fe/SiO2 mass ratio from 1.1 to 1.7 were carried out in the temperature range from 1273 to 1573 K. The results are presented in the form of pseudoternary sections “Fe2O3�-ZnO-(PbO+CaO+SiO2). The X-Ray and SEM-EDS results showed that the slag compositions of this study are in the spinel franklinite (ZnFe2O4) primary phase field. Hardystonite (Ca2ZnSiO7) and calcium and lead silicates are formed between 1100°C and 1200 °C. The results obtained from experimental and FACTSage calculations showed that increasing the CaO/SiO2 ratio for Fe/SiO2 = 1.1 to 1.7 decreases the liquidus temperature.

The world's growing awareness of climate threat and pollution enhances the demand of new environmentally and economically superior processes and system concepts for the reduction of emissions in combination with increased efficiency even for raw material industries. Although fluidized bed processes are well established in the field of metal extraction, the use of plasma or microwave radiation, combined with an adjusted process control enables completely new perspective for process innovations. In a joined R&D-project Outotec together with InVerTec and the University of Bayreuth developed a pilot plant process for study of microwave and plasma assisted thermal treatment of ores under industrial conditions. Usually ores are extremely heterogeneous multi phase minerals with locally changing dielectric properties. In the paper the treatment of a carbon containing gold ore is discussed. The leachability of gold from the ore is mainly determined by the remaining content of Total Organic Carbon (TOC). The main objective of calcination is therefore removal of carbon to the minimum amount possible in large scale processes. The presence of carbon in the ore enables local overheating in a microwave field and oxidative removal of organic carbon at moderate macroscopic temperatures. The fluidised bed reactor is based on the Outotec Circoroast process for the calcination of ores in an annular fluidized bed. The modified 2 zone annular fluidized bed reactor enables microwave induced overheating of the organic carbon, while unwanted sintering and agglomeration of the ore particles are suppressed by a cyclic movement of the bed material between an area of high microwave field intensity and a colder annular zone. To realize the concept of roasting far from the thermal equilibrium in the technical scale, a special microwave feeding system has been developed. In the paper, the results of the test campaigns with a throughput of 5 kg of ore/h are discussed. Depending on the operating conditions, a substantial increase of gold leaching can be achieved. Since microwave energy compared to fossil fuel is expensive, the challenge is to minimize the microwave use without losing the positive effect of microwave treatment. The patent pending technical solution to resolve this conflict will be presented in the paper.

Most of the SO2 produced in the pyrometallurgical processing of non-ferrous metals is currently used to make sulfuric acid. This process, initially conceived as a way to mitigate atmospheric pollution with SO2, has become in some particular cases a source for additional income due to local or geographical demand of sulfuric acid mainly for the use in hydrometallurgical processing of ores. However, the convenience of sulfuric acid production from smelter gases is currently scrutinized due to the increasing instability of the local acid market and the increasing interest of developing alternative methods to treat the SO2 from the gaseous effluents in nonferrous smelting processes. In this framework, this paper presents a critical review of alternative methods to treat SO2 laden smelter gases to produced elemental sulfur in order to comply with ever stringent environmental regulations as opposed to the conventional method of producing sulfuric acid from the SO2.

In this study, nickel pig iron alloys were synthesized by carbothermal reduction of lateritic nickel ores obtained from west Anatolion region of Turkiye. At the beginning of the study, the calcination process was applied on the lateritic ore which is containing 1.58 wt. % Ni and 0.12 wt. % Co by using in a semi-pilot scale rotary furnace at 1100 °C for 1 hour. Then, a mixture of calcined ore and metallurgical grade charcoal was prepared and charged into a sintered alumina crucible. Carbothermal processes were carried out by using a graphite resistance tube furnace at different time (0- 60 min) and temperature (1450-1600 °C) under inert argon atmosphere. The raw materials, alloys and slags were characterized by using wet chemical analyses, XRD (X-Ray Diffractometry), and EPMA (Electron Probe Micro Analyzer) techniques.

In more than 20 years, huge numbers of studies have been explored to make clear the mechanism of unexpected behaviors in microwave processing, for examples, the crystallographic transitions from microns to several tens nano meters on magnetic materials involving unpaired spin in 3d orbit under the exposure in magnetic field of microwave the rapid sintering of many kind of ceramics without crystal growths and the synthesis of natural super-lattice structure in the binary system, etc. The striking similarity of ultrasound and microwave at high temperature remained us the word of “coherency�. The Gibbs free energy (G = H – TS) contains two different ordering terms that are the disordered thermal motions (origin of high entropy) and the coherent kinetic motions with microscopic ordered structure (origin of low entropy). As the microwave processing uses monochromatic frequency, the electric or magnetic fields generate ordered motions in the material first. The entropy of coherent phonons is lower than the random motion of thermal photons. It experiences various non-thermally equilibrium stage of entropy and finally to reduced to thermally equilibrium stage. H. D. Kimrey reported that the activation energy from the relation of sintering rate for alumina to reciprocal temperature showed a drop in activation energy from 575kJ/mol to 170 kJ/mol for microwave sintering. The decreasing of activation energy has been observed in the reduction process of Titanium oxide (TiO2) under the irradiation of microwave magnetic field. The fall of energy can also be seen on the phase transitions. For example, the nano-crystallographic of ferromagnetic powders in which the hard magnetism converted to very soft one. These experiments show that the microwave couples with different energy path on the phase transitions. These phenomena require very sophisticated studies of renormalization theories, and molecular dynamics such as ab initio calculation.

Bubble column reactors are employed in various pyrometallurgical smelting and refining processes. A fundamental understanding of their operation requires detailed information on the hydrodynamic and thermodynamic phenomena governing the behavior of individual gas bubbles in the melt. In this work, the opportunities of a Hele-Shaw cell based experimental setup for investigating reactive gas bubbles in liquid metals are evaluated as an alternative to tomography techniques, which are often difficult to apply at high temperatures. Our setup consists of two transparent closely spaced parallel plates. The gap between the plates is filled with liquid metal and gas bubbles with a significantly larger equivalent diameter than the gap width are injected in the melt. The relatively high surface tension of the liquid metal prevents the formation of a wetting layer between the bubbles and the wall, making an accurate tracking of the gas-liquid interface possible. In this way, bubble properties and 2D flow patterns in the system can be monitored under controlled circumstances and therefore the setup allows a straightforward in-situ study of the interactions between thermodynamic and hydrodynamic phenomena. Results will be shown of dimensional changes of bubbles due to mass transfer across the interface under different flow conditions.

The mexican mining company Minera-Mexico operates the smelting complex La Caridad, with El Teniente and Flash furnaces, a Pierce-Smith converter and a final electric slag cleaning furnace for the recovery of metal values, mainly copper. In this prometallurgical complex, concentrates from different plants from the company with different chemical and mineralogical compositions of copper and other elements are treated. The final discarded slag presents a typical content of around 1 wt% Cu and a gradual increase in the Mo content of around 0.4 wt% by some of the new available concentrates. In this work a global characterization of the copper pyrometallurgical slags from this plant is done, as a function of the chemical composition of the charges and the operation parameters in the smelting complex and compared with thermodynamic calculations for predicting the copper losses in the slags. Additionally, a slag cleaning treatment in an experimental Electric Arc Furnace (EAF) is carried out, using coke injection and also additives as CaF2 and MgO, with an effect on the increase in the metal values recovery. The characterization of the final slags showed a high metal recovery in the slag cleaning treatment with losses of copper of less than 0.5 %, mainly depending on the physicochemical form, and the lower losses by the use of additives in the slag with an effect of reducing its viscosity. Special interest is made in the behavior of Mo, but it seems its recovery should be made in previous stages. The final content of Mo in the cleaned slags was reduced in lower extent than that of Cu.

Slags are produced massively as a by product of the pyrometallurgical processes in the ferrous and non-ferrous industries. Therefore, large tonnages of slags have been historically accumulated during plant operation time. Currently slags are frequently used as base material in a wide spectrum of applications such as, road and harbour construction and railway ballast. However, there are some minor valuable components, with an appreciable market value today, which can be also recovered and hence give an additional value to the global economical balance of the metallurgical process. Thus, the slags can be valorised by the price of their minor components such as; Copper, molybdenum, vanadium, and some precious metals, and by the iron oxides and silica which are present in larger quantities or by their bulk properties as industrial minerals. Therefore, the present work shows some cases on slags processing, where a characterization and recovery of valuable elements and/or compounds have been done. The major and minor components of slags, the mineralogy and their influence on the chemical and physical slag stability are also discussed. The possibility to treat this stock piled by-product as a new resource, is considered with a brief economic analysis of the operation and investments costs involved.

Recovery of nuclear materials and rare-earths from spent nuclear fuel was examined by sulfide process consisted of sulfurization and acid leaching steps using the simulated fuel oxides. After the oxidation of UO2 pellet to U3O8 powder by voloxidation treatment, rare-earth in the sample were reacted with CS2 at c. A. 673 K forming oxy-sulfides or sulfides, while uranium oxides remained without sulfurization. Then oxysulfides and sulfides were separated by dissolution into nitric acid and nuclear materials such as uranium and plutonium were recovered as oxides. The conditions for selective sulfurization were also discussed.

A variety of carbonaceous reductants are being used in the production of ferrochromium. Matching the correct carbon reductant for each specific process and product requirements has become a vitally important function in the ferrochromium industry. In numerous cases the substitution of a reductant with a new one despite being similar in all relevant chemical specification characteristics to previous material has resulted in different performances. In this study the reducibility of chromite and reactivity of carbonaceous reductants has been simultaneously studied experimentally using the thermo gravimetric analysis (TGA) technique. The chromite ore was reduced by graphite, coal, charcoal and coke in the temperature range 1000oC to 1300oC under an inert argon atmosphere. Particle size range was +50-100, +100-150 and +150-200 microns. The results clearly indicated the temperature and particle size dependence of the reduction process. The experimental data was then fitted into the Arrhenius model to be able to obtain the indication of the reactivity of the reductant through the calculated activation energies. A generalized rate model was also used to describe the reduction of chromite which has shown that at a given particle size the rate of reduction was initially controlled mainly by interfacial area chemical reaction later switching to diffusional control.

Even in times of crisis it is evident that the discontinued use of production facilities in metallurgical plants has considerable influence on the lifespan of refractory linings. Standstills and the associated furnace cooling increase the risk of gaps occurring that can become infiltrated during heat-up. Since Pb and Pb-alloys have low melting points, complete sealing of gaps can start at 900–1000 °C; However, it is necessary for the operators to maintain this temperature for a certain period of time during heat-up to enable the infiltrate to melt. Ever stricter legislation regarding secondary lead plant operations complicates the correlation between refractory material application and the specific refractory material consumption in SRF. In addition, RHI has recognized that constant material developments as well as information directly from the lead production plants are essential to further develop grade concepts that were effectively used up until the legislative changes. This new grade concept must withstand the new process conditions and thereby avoid any furnace downtimes due to excess wear in any furnace areas (i. E., slag zones and end walls of SRFs). The secondary lead industry is facing a positive outlook based on the developing markets, as long as the environmental legislation can be met in the relevant production country. It is important to highlight that constant and close collaboration between refractory supplier and consumer, in the form of continuous discussions and jointly addressing problems, can positively influence refractory consumption and ensuing costs (e. G., standstills and production losses). Through consistent cooperation, based on confidentiality and loyalty, RHI is committed to a forward-looking approach that benefits all partners involved.

Retorts have been first introduced in metallurgy in the thirteenth century for the production of zinc and were used because the metal has to be distilled off during reaction. The technology was applied later in the sixteenth century for the production of mercury, and in the twentieth century for magnesium. The retorts are heated in a furnace and the combustion gases do not come in contact with the metal to be distilled, i. E., heating is indirect and therefore not efficient. The retorts may be operated at atmospheric pressure or under high vacuum. Operation is conducted batch-wise: The retort is filled with the reaction mixture, heated externally, and the metallic vapors collected in a suitable condenser. When reaction is complete, the retorts are removed from the furnace, cooled, emptied, and recharged by another batch. Retorts made of clay were extensively used but now obsolete. Continuous distillation has also been introduced. A historical review will be given and recent developments will be discussed.

Environmental impact of extraction of natural resources is today in the focus and mining and metallurgical activities to produce metals are not the exception. Copper content in ores today is around 1% and that implies necessarily to eliminate, in some way, around 99% of non useful material. A lot of attention has been pay on metal losses, then trying to recover the maximum of copper from some wastes produced. However, not a lot of attention has been done on those wastes containing other materials, but with some practical use today in various others activities in our society. This presentation will propose some alternatives of use for some wastes coming out from the copper extractive industry, particularly those representing a big amount after extraction processes (gases, tailings, overburden, slags), with special attention to sub products generated during smelting steps (slags). The results of some researches developed over copper slags at the University of Concepcion, where a plant design to recover some valuable metals has been established, make possible to find economical alternatives for these kind of wastes, and, by this way, diminish strongly the environmental impact of the copper mining industry. Results obtained specifically for slags, showing recovery of various metals as well as the utilization of other contained materials will be shown. As promissory results, it is expected to extend this kind of research to others wastes in the mining and metallurgical industry.

In these times, recovery and recycling are words commonly used and abused. Our current way of living is generating substantial waste materials that contain substantial value. It is important to recover this value with the minimum consumption of resources and energy. In many cases, this approach can be the basis for a good business plan. Engitec Technologies, active in lead recycling for decades, has also developed other processes to treat secondary sources to economically recover the contained value. This presentation will review the Engitec approach for recovering non ferrous metals and other valueable materials from secondary sources.

At the Cu2007 SMS Siemag presented a copper slag cleaning simulator, which had been developed by Professor A. Warczok of the University of Chile. The now presented simulator is for a 6-in-line FeNi smelter, similar to the ones now under construction by SMS Siemag in Brazil for Vale Inco and Anglo American Brasil. It is targeted to present the results of simulating the actual smelting behaviour of the furnaces with production data. These furnaces will go online in the following months.

Sustainable smelting requires technology that can process metallurgically complex, low-grade, fine ores, and waste materials, as well as the more desirable ores. Electric smelting in an open-arc open-bath direct current (DC) furnace provides the required flexibility for this type of processing. DC arc furnace technology was first used for smelting applications in the mid 1980s, and has subsequently been applied industrially to the smelting of chromite for the production of ferrochromium, the smelting of ilmenite to produce titania slag and pig iron, and the recovery of cobalt from non-ferrous smelter slags. Newer applications of this technology involve the smelting of nickel laterites to produce ferronickel, and the smelting of oxidised concentrates containing platinum group metals (PGMs).

CaO-SiO2 based slag is commonly employed in the steel making industry and is also a candidate for refining molten silicon. In order to understand the mechanism of impurity removal from metal phase to slag phase at the slag/metal interface, it is important to elucidate the local structure and behavior of the impurities in molten slag. In the present paper, the local structure of 11B in the CaO-SiO2-BO1.5 system and 31P and 29Si in the CaO-SiO2-PO2.5 system were observed using the Magic Angle Spinning – Nuclear Magnetic Resonance (MAS-NMR) and their composition and basicity dependences have been investigated. In the CaO-SiO2-BO1.5 system, the boron existed as trigonal boron species (BO3 groups, denoted here as [3]B) as well as tetrahedral boron species (BO4 groups, [4]B). In the studied composition, the fraction of [4]B to total boron species decreased with increasing the basicity. On the other hand, in the CaO-SiO2-PO2.5 slag system, phosphorous existed as monophosphate ion, (PO43-), and this phosphate ion structure was independent of the slag composition and basicity. However, the number of bridging oxygen around silicon increased with the increase in the PO2.5 concentration.

The structure and the properties of slag melts produced in the course of continuous converting of nickel containing copper matte and concentrates were investigated. The structures of slag melts were studied with the use of the methods of X-ray phase analysis, raster electron mi-croscopy and electron probe microanalysis. The slags liquidus temperature was determined by the way of differential thermal analysis. Density, viscosity and surface tension of slag melts were defined. The investigations were carried out in a wide range of slags composition varia-tions depending on: SiO2/CaO ratio in slag; Charged flux amount, Cu/Fe ratio in the processed matte.

China has the most abundant mineral resources of titanium around the world, more than 90% of which is deposited as the vanadium-titanium magnetite ore. Through the current process, most of titanium element indwells in Ti-containing industry slags. Ti-containing slag is acknowledged as an important secondary resource in china. And the utilization of Ti-containing slag has attracted much attention in recent years. However, the extraction of Ti element through the existing approaches results in high cost and heavy pollution. Selective enrichment method is proved a better way to improve the recovery efficiency of Titanium. The present paper investigated the extraction of Ti element from Ti-containing slags through selective enrichment method and confirmed the Ti-enrichment phase under different slag compositions. The crystallization behavior of the Ti-enrichment phase and the related mechanism were also discussed in this work.

Atlas, containing description of 20 ternary systems for lead alloys substitution, has been published. In spite of enormous work fulfilled, it contains only liquidus projections, invariant reactions tables, 2-3 isotherms and some isopleths for every T-x-y diagram. Obviously, it is not a real device to design the heterogeneous materials. Special technology to reconstruct a space T-x-y diagram with all set of its geometrical elements in dependence of a scope of experimental and calculated data (beginning from phase transformation scheme via primitive template as surfaces set, given by their additive contours, to perfect thermodynamically regulated computer model) has been elaborated. Every surface is given by interpolate Lagrange polynomial and is constructed cinematically. Main difficulties of T-x-y diagrams computer models were connected with the fact that the liquidus does not contain all information about the system properties. Computer models of Au-Bi-Sb, Bi-In-Sn, Ag-Cu-Sn systems had been designed by incomplete data of the Atlas. Additional efforts were made for the sub-solidus regions, low-temperature allotropies and exothermic compounds. So, 3 from 8 binary compounds of the Ag-Cu-Sn system has not exit on the liquidus. Two from them have upper and low temperatures of decomposition and third one is the low-temperature allotropy and participates in the eutectoid transformation with a Sn modification. In Ag-Cu-Sn system there are 14 invariant and 37 monovariant transformations, its T-x-y diagram consists of 233 surfaces and 81 phase regions. Reconstructed (and verified by 2 isotherms and 5 isopleths of the Atlas) computer model helped to detect some errors: Homogeneous regions of Ag and one binary compound are degenerated on some isotherms, but according to the invariant reactions they must present on corresponding sections. Such kind of computer models help to calculate mass balances on different crystallization stage and detect the origin of crystals, to search the mistakes in the graphics of real diagrams sections.

Secondary copper facilities have to deal with a big variety of raw materials which are significantly different in respect of valuable metal content, trace elements and impurities. Furthermore, the providers of industrial equipment offer a diversity of vessels for smelting, converting, refining and recycling. For this reasons no two smelting facilities are exactly the same and have to be designed individually. Due to different suppliers, processes are normally designed part for part and optimized for a single step. As a result, a suboptimum is achieved in capacity, economy and ecology. The present paper shows the possibilities of process modeling in the secondary copper metallurgy for the engineering of a state-of-the-art recycling process. Aim of the modeling is to design the pyrometallurgical facilities as well as the material flows and energy balances. The amount of consumables and auxiliary materials should be calculated for an optimized process. In principle, the desired raw material composition and mix defines the process, but the vessel where it is charged as well as the addition time should be found in respect of minimum energy consumption. A well reasoned model is an interaction of thermodynamic software packages and empiric data. Automated calculations allow an easy mass and energy balancing based on Gibbs minimization. However, kinetic influences and/or insufficient thermodynamic data result in a difference between real and ideal behavior. These deviations can be neglected in some pyrometallurgical operations but have to be considered especially in case of kinetic controlled processes. The presented model shows how empiric data based on experience can be combined with the theoretical thermodynamic model to best possible reproduce the real process.

Titanium deoxidation equilibrium relations in liquid Fe-Ni, Fe-Cr and Fe-Cr-Ni alloys which were saturated with `Ti3O5` and Ti2O3 phase, were evaluated in present paper. The effect of temperature and titanium content on evaluated in those alloys, and the equilibrium oxygen content in each alloy increased with increasing equilibrium temperature and with decreasing titanium content. In order to fix the activity of deoxidation product, `Ti3O5` were used in crucible material. The deoxidation product were analyzed by FE-SEM EBSD method and the solubility of alloying elements - Fe, Ni and/or Cr, were done by SEM EDS. From the present experimental results, the activity coefficients of components were estimated by Redlich-Kister polynomial. The equilibrium relation between titanium and oxygen in those alloys were estimated using deduced Redlich-Kister polynomial parameters and compared with the experimental results and it was confirmed that the estimated titanium deoxidation equilibria were coincided with experimental results.

There are many reasons why sulfur represents one of the most important part in the copper pyrometallurgical processes. The most of the copper sulfide concentrates contain approximately 1 to 1.5 ton of sulfur (2-3 t SO2) per ton of the produced copper. Sulfur has chemical, technological, energy and ecological importance in the copper smelting processes. In the last decades, energetical and ecological aspects of sulfur are the most considerable and the best solutions are incorporated in the autogenous copper smelting processes.

The advantages of two-zone Vaniukov’s furnaces are studied in comparison with one-zone furnaces and the alternative autogenous processes. There are presented the results of the in-vestigations and pilot testing of different processes in a two-zone Vaniukov's furnace. There is shown the possibility to use two-zone Vaniukov's furnaces for processing the following types of raw-materials containing heavy non-ferrous metals: Copper and nickel sulfide ore concentrates, oxidized nickel ores, lead concentrates with zinc content, gold containing con-centrates, zinc containing slag, copper matte and rich copper concentrates.

In the production of manganese ferroalloys, creating a freeze lining is a wellestablished technology applied in furnace containment system designs. Heat transfer calculations are utilised in the design of these systems and in monitoring the condition thereof during operation. Inputs to these calculations - i. E. The coefficients of thermal conductivity and thermal convection - have to be determined experimentally. Published, scientific data is limited. The authors illustrates the relative importance of the coefficients of thermal conductivity and thermal convection on the thickness of a freeze lining by conducting a sensitivity analysis on a onedimensional heat transfer calculation for a circular furnace. They report coefficients of thermal conductivity measured for natural, rich manganese-bearing slag cooled at different cooling rates. The slag was cooled at different cooling rates to create slag samples with a glassy structure or a crystalline structure. The coefficients of thermal conductivity were measured utilising the lazer flash measurement technique in the temperature range room temperature to 1000 oC.

The following statement will be discussed herewith ‘Real solid, liquid and gaseous solutions of any composition (and pure gases) gradually approach the state of an ideal solution (perfect gas) as temperature increases (approaches infinity) at any fixed pressure. All excess thermodynamic properties of real solutions gradually approach zero if the reference states of all the components are selected as pure components in the same state as that of the solution and if the concentrations are expressed in mole fractions’. Initial validation of this statement is demonstrated here for high-temperature alloys. Equations describing the temperature dependence of excess Gibbs energy of mixing in accordance with this statement will ensure that artificial inverted miscibility gaps will not appear in the calculated phase diagrams as they often appear when this statement is not obeyed. Different equations will be discussed from this point of view. The above statement is shown to possess all the properties (both good and bad) of a thermodynamic law: I. General validity, ii. Impossibility to prove with a 100 % certainty, iii. Simple reasoning behind with close to trivial statement and iv. Usefulness in interpreting natural phenomena using computational thermodynamics.

The change of congruent crystallization L->D+Ru (D=TiIr3) to incongruent one L+D->Ru has been found in system Ti-Ru-Ir . Analogous change of crystallization type from incongruent L+D->F to congruent L->D+F (D=ZrIr3, F=ZrIr2) has a place in system Zr-Ru-Ir . The same type of eutectoid-peritectoid transformations exists in other metallic systems . Special surface corresponds to changing of phase transformation type in 3-phase regions . At this moment a 3-phase reaction becomes ad interim as 2-phase one in presence of third phase. Passive role of this phase f means that the transformation of its mass portion changes the sign: Dm(f)=0. Conditions dm(f)=0 for every of three phases give in any 3-phase region 3 virtual 2-phase surfaces. Every of them can be real at concrete temperature-concentration condition. 2-phase surface is also a ruled one. As for T-x-y-z diagrams, 3-phase region L+a+b have boundaries in a form of the ruled hyper-surfaces with horizontal generated segment, which slides on 2 from 3 directing surfaces which form a phase region. There is the isothermal curve at temperature T on every of 3 directing surfaces. If these 3 isotherms are given by one parameter t then 3 points at the same 0 < t < 1 on every isotherm produce the triangle Lab. In dependence on temperature-concentration conditions it is possible that this triangle has a line which belongs to the hyper-surface dm(f)=0, where f=L, a, b. Changing the parameter t from 0 to 1 forms the isothermal at T ruled surface. The ruled hyper-surface with horizontal generating line is formed from such ruled surfaces at different T. This hyper-surface corresponds to 2-phase reaction with indifferent third phase too.

Marked by reliance on carbon as a reducing agent, modern metallurgy is intrinsically incapable of achieving sustainability. For example, in round numbers it takes ½ tonne of carbon to make a tonne of steel; In parallel it takes about ½ tonne of carbon to make a tonne of aluminium. Molten oxide electrolysis (MOE), which is the electrolytic decomposition of a metal oxide into molten metal and oxygen gas, is put forth as a low-carbon alternative. In its most advanced embodiment MOE avoids the use of consumable carbon anodes and halide electrolytes; This eliminates the need for energy-intensive anode manufacture and guarantees the absence of greenhouse-gas emissions as the by-product of the metal-recovery step. Instead, tonnage oxygen is the by-product of electrolytic metal production. In the author’s laboratory a variety of metals have been produced by MOE including iron, nickel, chromium, manganese, silicon, and titanium, each by electrolytic decomposition of the related metal oxide. So, for example, to produce iron by MOE, molten iron oxide is decomposed by the action of electric current into liquid iron and oxygen gas at a temperature of 1575ºC. What sets MOE apart from all other metal producing technologies is that in the extreme it is totally carbon-free and, hence, generates no greenhouse gases (GHGs). Promising results for a low-cost, oxygen-evolving anode have been obtained. Furthermore, MOE may even prove to be an enabling technology in human colonization of space, which must rely upon in situ resource utilization to the fullest extent. The extraction of iron and silicon with co-generation of oxygen has been demonstrated in laboratory-scale cells charged with lunar soil simulant NASA JSC1-A. Beyond sustainable metals production, MOE can serve as the inspiration for scalable electrical energy storage in stationary applications. Liquid-metal/molten-salt cells have been shown to operate as rechargeable batteries that have the potential to handle colossal currents thereby enabling us to store off-peak power from the grid for subsequent delivery on demand during high-usage periods.

The study of smelting low ferronickel from pre-concentrate nickel-iron ore with 2.76%Ni and 38.00%Fe was carried out to find an effective way for stainless steel enterprises to use the low nickel laterite reasonable. The results show that Ni and Fe have a certain degree of enrichment, and impurities and harmful elements have different degrees of reduction after pre-concentration of nickel iron ore. Most valuable metal did not compound with impurities which greatly accelerated the speed and extent of melt separation reduction. Good alloy of 6.58%Ni with the overall recoveries of 93.38% and 89.95%Fe with the overall recoveries of 89.57% was manufactured under the following conditions: 10% coke, 1.0 basicity, 18% MgO and 3% Al2O3 of slag, melting at 1550℃ for 10min. The product can be used for the feed of producing stainless steel.

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