Search Documents

By Andreas Nolte

This paper includes a comprehensive report about the metallurgical utilisation of reusable products from electronic scrap recycling, car shredding industry, used glasses an various waste products, such as slimes and flue dusts, generated in a secondary copper smelter. Depending on the copper content, the type of copper compounds and the characteristics of accompanying substances, the materials are treated by smelting in furnaces, operating under reducing or oxidizing conditions. HKs pyro- and hydrometallurgical processes, blast furnaces, converters anode furnaces, tin lead alloy plant and tankhouse will be outlined. The reusable products are categorized according to the origin of the materials and then presented in the form of quantity and quality balances. Processing methods, process able quantities and quality requirements of inputs are described. The utilization degree of the most important metals (copper, tin, lead and zinc) is described with graphics. The report is rounded by information on operating licence according to the environmental regulations of the Federal Republic of Germany and data concerning supply and contracts

Jan 1, 1997

By Grigore Matei

The thermodynamic properties of CU2S-FeS system are important not only in the case of copper smelting but also in the case of general pyro-mctallurgy, However there are not many reported activity data In this study, activities of FeS and CU2S in the CU2S-FeS system were calculated using the Darken's method from the activity data of the CU2S-FeS-Sb2SJ systems measured by the transportation method at 10S0°C. The activities of CU2S and FeS in the CU2S-FeS system showed negative deviation from the ideal behaviour and satisfied the relation of the Gibbs-Duhem equation,

Jan 1, 2003

By Marcel Sturzenegger

Though the extraction of copper is well established, generation of sulfur dioxide (S02) is still a troublesome issue. Conventional processes are further challenged by the increasing amount of impurities in the concentrates. Direct decomposition of the metal sulfides into the metal(s) and elemental sulfur under concentrated solar radiation offers a promising path to solve both problems. Thermogravimetric measurements under inert atmospheres have shown that synthetic chalcocite or chalcopyrite yield copper at temperatures as low as 1773 K. Even though optimum reaction temperatures might be somewhat higher, such temperatures are straightforwardly accessible in solar chemical reactors. The absence of oxygen will reduce the extent of slag forming reactions and thereby alter the evaporation characteristics of volatile impurities such as arsenic or antimony. Chemical equilibrium calculations for a chalcopyrite-enargite feed, e.g., have shown that under inert atmospheres arsenic compounds are completely evaporated at temperatures above 1000 K and an effective separation of arsenic from the matte is expected. An important step towards a solar production of copper is the design and testing of prototype solar chemical reactors for this reaction. Numerical modeling is a key tool supporting a rational design but it requires data of the high-temperature properties that prevail in these processes. Development of techniques for determining the essential quantities such as decomposition rates or radiative properties at temperatures up to 2000 K is therefore a main activity in our laboratory in order to control and optimize the process. Though developed in the frame of high-temperature solar technology, the experimental techniques are also suited to advance the understanding of conventional high-temperature processes. Keywords: Solar technology, Sulfur dioxide, Solar Radiation, Thermogravimetry, Chalcocite, Chalcopyrite, Numerical modeling.

Jan 1, 2003

By E. A. Thiers

The causes of structural changes in the markets for high technology alloying metals are discussed in terms of technological, economic, and financial trends. Recent market imbalances have affected producers in developed and developing countries differently. Possible response strategies for suppliers in the two types of countries are examined that may alleviate future market imbalances.

Jan 1, 1988

By Eiji Iwamura

"Two types of diamond-like carbon (DLC) films with different microstructures were prepared by unbalanced magnetron sputtering, and the tribological properties of the nanoscaled DLC multilayer coatings consisting of alternating layers of graphitelike and amorphous-like microstructures were examined. The DLC microstructure was characterized by certain features of graphite-like clusters, in that some of them had onion-like structures. The films filled with the clusters were obtained in a condition with an incidence of high influx of energetic electrons, and the other films without apparent cluster structures were formed in a condition with ion bombardment controlled by negative bias voltage applied to substrates. Stacking each film layer-by-layer, the nanoscaled multilayered coatings showed superior tribological properties to individual single-layered films due to the combination of properties induced by the difference of microstructures.IntroductionIn various tribologiql applications, it is necessary for diamond like carbon (DLC) coatings to have adequate adhesion, significant hardness and a concomitant low friction coefficient. A number of deposition techniques and coating structures have been proposed to achieve suitable DLC properties [1-3]. However it is still difficult to obtain a satisfactory level of combination of the properties particularly desirable for engineering applications.In this study, the features of unbalanced magnetron sputtering were demonstrated with the effect of ion and electron bombardment. Two types of microstructures , namely amorphous-like and graphite-like, were prepared by changing the condition of the charged particles bombardment during deposition. Using the difference of properties induced by the microstructures, nanoscaled DLC multilayered structures were examined in an attempt to improve tribological properties."

Jan 1, 2000

An EAF dust generated in a Swedish steel mill has been leached in hydrochloric acid at The solution obtained has been subjected to purification by cementation followed by precipitation of zinc with sodium carbonate. The thermal decomposition of the precipitate was studied using thermal analysis and X-ray diffraction. The results show that during the calcination of the precipitate three different reactions occur. The decomposition of the solid phases Zn5(CO3) (OH)6, CaZn(CO3)2 and CaCO3 occur completely at 370°C, 560°C and 940°C respectively, yielding a final product containing 61.9% ZnO and 38.1% CaO. Methods to minimize calcium and manganese in the final product are discussed.

Jan 1, 2003

By Tuomas Hirsi

The world’s first large scale modular solvent extraction plants have been delivered by Outotec. The first of these is now in operation and has proven that the VSF®X technology can deliver the excellent performance of the Outotec VSF® solvent extraction process. Modular delivery allows site work to be minimized and the manufacturing done in a controlled environment, allowing for serial production manufacturing benefits. Container based delivery was found to be a highly efficient way of utilizing the standardized transportation methods on a global scale. Site work with modular units was found to be efficient and highly predictable. In this paper, we present the first successful Outotec VSF®X deliveries and discuss the benefits of the modular delivery and design compared to the standard solvent extraction installation’s delivery. The process performance of the VSF®X is also discussed with experiences from the first industrial reference presented.

By Robert Corson

Zinc has a large solubility in Fe and a completely filled ?d? shell. With the discovery of dramatic increase of the magnetostriction in Fe by Ga addition, an examination of element Zinc that is adjacent to Ga in the periodic table is of significant interest. In this work, the effect of binary alloying of Zn with Fe on the magnetic and magnetostrictive properties is examined. The FeZn alloys were processed using powder metallurgy and vapor phase synthesis, and Zn contents were varied from 5% to 30%. An examination of the influence of different processing parameters and the Zn content on the resulting alloy properties is presented. The alloys were characterized using X-ray diffraction and SEM. Magnetostriction measurements were carried out at different pre-stress levels. Magnetic properties were measured using a vibrating sample magnetometer.

Jan 1, 2006

By E. S. Peterson

The selective separations of trace metals- and organics from water are processes of importance to industry. The application of a new metals capture technology coupled with polymer membrane technology has proven to be one avenue to accomplish such selective separations. The polymers used in these studies are polyphosphazenes. Polyphosphazene polymers consist of an alternating backbone of nitrogen and phosphorus atoms. The polymers have high thermal and chemical stabilities. Experiments at the Idaho National Engineering Laboratory demonstrate that polyphosphazene membranes coupled with Chromato Chem,"Chelation Chromatography" process are capable of removing both chlorinated hydrocarbons and metal ions from process streams. These results point to a wide range of potential industrial and environmental applications for such systems. Data will be presented which show the efficiency and selectivity of separations, postulated separation mechanisms, and the initial designs of industrial demonstration units which are currently under construction. Parts of this work have been performed under a Cooperative Research and Development Agreement (CRADA) between ChromatoChem, Inc. and Idaho National Engineering Laboratory (INEL). The work at INEL was been sponsored by the United States Department of Energy's Office of Industrial Technologies

Jan 1, 1995

By S. Peng, Vaughan R. Voller

"Free boundary problems are a common occurrence in materials processing operations. An important example is the filling of material into molds. This paper looks at filling problems associated with polymer processing, in particular Resin Transfer Molding (RTM) and Compression Molding. A general, single governing equation is developed which on numerical solution provides predictions for the position of the polymer front in the mold during filling. Both fixed and deforming finite element solutions are developed. Application to polymer filling test problems reveal that the fixed and deforming grid scheme are accurate and compare closely with each other.IntroductionProblems arising from the analysis of material processing operations often involve the tracking of a moving boundary, on which a balance conditions needs to be met, or the locating of a free surface that defines the solution domain. Material processing examples of so called ""free and moving boundary problems"" include; the tracking of solidification/melting fronts[l], the tracking of the metal/gas interface during the filling of a mold[2] and location and shape of a skull (freeze line) in a melting furnace[3].Computational solution of free and moving boundary problems usually fit into one of two classes, viz.1. Fixed grid scheme: In which the spatial domain is covered by a fixed grid (mesh) of node points and the solution uses an auxiliary variable (e.g. a local liquid fraction) to track the moving boundary or locate the free surface.2. Deforming grid scheme: In which the grid in the spatial domain is continuously deformed (or adapted in a steady state problem) such that a specified set of grid points lie on the moving boundary or the free surface.Details on the basic underlying features in these two classes of solution can be found in the excellent monograph by Crank [4]."

Jan 1, 1994

By Larry M. Southwick

The smelting of copper and other non-ferrous metals have made considerable advances over the last 125 years. Many of the ideas and processes currently in use were attempted early in the history of smelting and were unsuccessful. Often the cause was incomplete understanding of the metallurgy involved, inadequate refractories, poor materials of equipment fabrication or trying too many new ideas at once. With time, these problems get solved and the technologies become commercialized .These were processes whose time had not come when originally proposed, but did eventually. On the other hand, there have been some concepts whose time will never come. They were impossible then and they are impossible now. The people that dream these up were either crackpots (they didn't know what they were doing, but thought they did), or charlatans (they knew they didn't know what they were doing, but didn't care). Both rely on bad science to propose metallurgical absurdities. These too have their place in the development of technology, though mostly negative, and several examples will be discussed in this paper. Three from around the turn of the century will be covered, as well as one from this decade. The last demonstrates that the art of creating absurdities has not withered, even after ninety years of scientific sophistication, and some can even be patented. The first three reached field trials due to the gullibility of company management. The last arose from a fortuitous mis-operation of a plant which solved a problem, but the explanation and patent which arose are metallurgically impossible.

Jan 1, 1999

By J. Phillip Mackey

The Peter Hayes Symposium on Pyrometallurgy, held as part of Extraction 2018, is an acknowledgement of his contributions to the basic science and principles underpinning modern pyrometallurgical processing. After completing his PhD at Strathclyde University, Scotland, in 1974, Peter took up a teaching position at The University of Queensland, Brisbane, Queensland, Australia in 1976. Peter Hayes’ research at the University since then has been focussed on: • The mechanisms and kinetics of heterogeneous solid/solid, gas/solid and liquid/ solid reactions, and • Experimental measurement of phase equilibria in complex high temperature metallurgical systems. This paper provides a brief biography of Dr. Peter Hayes and gives a full listing of Peter Hayes’ publications.

By Steven C. Torma

The present article reviews some of the technologies available for recycling high-energy yield explosives loaded projectiles. These activities lead to reduction of military ammunition stockpiles and their conversion into commercial and industrial applications. The recycling technologies involve dismantling and separation of ammunition components into recyclable metals, plastics, paper and explosive materials. The metal 1 ic components will be sent to smelters, where they will be converted to products that can be used in a variety of industries, such as construction, automotive, housing and so on. Plastics and paper will be recycled and reused. Explosives will be recycled to be used for industrial purposes in the mining industry. Propellants (ammonium nitrate and ammonium perchlorate) can be ground to small particle size and treated to be used in the agricultural industry as fertilizer. In addition, some of the excess explosive material recovered in the demilitarization process may be incinerated to produce energy for steam production for heating purposes, or for production of electricity. Furthermore, this article reviews the developments in the bioremediation of explosive contaminated soils and industrial effluents.

Jan 1, 1994

By H. Y. Sohn

The ignition and combustion of chalcopyrite particles under suspension-smelting conditions, in which the particle-particle interaction is neglected, has been analyzed by considering the intrinsic kinetics of oxidation and heat and mass transfer between the particle and its surroundings. Reasonable agreement has been obtained between the calculated results and experimental results from a laminar-flow furnace reported in the literature. This computation- al procedure has further been applied to flash-smelting conditions. Under suspension-smelting conditions (Sh = Nu = 2), chalcopyrite particles ignite at around 960 K. The effects of various parameters, such as oxygen concentration, particle size, and gas temperature, have also been evaluated. Comparison between calculated results in this work and experimental observations indicates that SO is the important gaseous product that forms at the surface of the particle.

Jan 1, 1993

By I. S. Blair

The introduction of the 36 MVA smelting furnace at Mufulira, and the experience gained during the first five years of operation have been described previously (6). Based on this experience the furnace was rebuilt in 1977., Details of the modifications made during this rebuild are described. Subsequent to the rebuild, refractory failures, particularly in the electrode ring bricks of the sprung arch roof, continued to cause concern, and repair and improved roof control methods are described. Electrode breakages continued, but developments in casing design and electrode preparation have resulted in significant improvements. Modifications in the electric furnace gas handling system are outlined, together with details of further changes to be implemented in the near future. The systems developed for metallurgical control of the furnace and the thermo-dynamics of the process are discussed. The electric furnace at Mufulira is now operating at above design production levels, and has decisively justified the choice of this technology in situations with inexpensive electric power. The potential for further increases in production capacity from the Mufulira unit, and improvements in design for new units are discussed.

Jan 1, 1983

By David Norval

Ni, Co, Cu and Pt, mattes are common materials that require granulating and milling of the resultant granules for further processing. This route is acceptable if the material is brittle (friable) which is a property associated with the higher sulphur mattes. For lower sulphur levels, where the matte is less amenable to milling, the costs of the milling increases. This paper will compare water granulation with certain dry granulation processes and the downstream processes required for Hydrometallurgy. It will further introduce and expand on atomisation which offers a further safety benefit in the control of the metal flow into the 'wet zone' with the use of a tundish flow control also reducing the conversion from the matte to powder in one fairly straightforward operation.

Jan 1, 2006

By M. Barkhudarov

The results are presented of research aimed at validation and development of a general purpose CFD code FLOW-3D. FLOW-3D is a commercial code developed by FLOW SCIENCE, INC. A number of physical modeling experiments involving the filling of cavities of different geometries with coloured water have been performed in order to compare the measurements with the results of computer simulations. Other numerical calculations were also done to be compared with the known analytical solutions.

Jan 1, 1992

By C. Burton Clark

The important role of the petrographic microscope in the petrology of refractories is discussed, based on 45 years of industrial experience by the author. Highlights of his career are used to illustrate improvements in equipment and techniques during the period. Two specific investigations are described which emphasize the interrelated use of the petrographic microscope with other instruments such as the x-ray diffractometer and scanning electron microscope. Emphasis is placed on the use of phase equilibrium diagrams for guidance in predicting and interpreting reactions that occur under non-equilibrium conditions in the manufacture and use of refractories.

Jan 1, 1982

By F. Z. Utyashev

The present work considers the essence of fragmentation: on the level of a simple model as a material response to the curvature accumulated by it at large deformations. It is on this basis that the correlation between curvature and fragment sizes is determined. It is shown that at deformation the area of curvature center inevitably changes. It is revealed that a specific value of variation of center surface area, i.e. ^As parameter, is numerically equal to the value of curvature acquired by a material. Minimum sizes of fragments and grains depending on ^As have been estimated, and the dependence of this parameter on strain has been established. Besides, the present paper considers the effects exerted by curvature center geometry, material distortion, directions of deformation and thermal warming up in the localization zones on structure refinement when various techniques are applied.

Jan 1, 2006

By Celaletdin Ergun, Ibrahim Erden, Gurbuz Gunes, Thomas J. Webste, Huinan Liu, Abdurrahman Bahadll

"B, Ti, Ag, AI and Cu substituted hydroxyl apatites were synthesized via precipitation method. Then the samples were air-sintered at 1300°C for 2 hrs and characterized with XRD, SEM, FTIR, and cell adhesion behaviors.IntroductionSynthetic hydroxylapatite (HA, Ca10(P04)6(0H)2) has a similar composition and structure to biological apatite. Therefore, it has been safely and extensively used as an implant material for bone substitute. However, synthetic HA has been used for a various applications including medical or non-medical applications, such as matrices for drug release control, bone cements, tooth paste additive, blood purification agent, monolithic implants or coatings on metallic implants, packing media for column chromatography, gas sensors, catalysis and host materials for lasers and luminescent materials, etc. [1-9].The major factors affecting the performance of HA on these applications are crystal morphology, density, porosity, pore size and distribution, chemical composition, and surface structure. As provided by the high flexibility of the apatite structure a great variety of cationic and anionic species can be substituted into HA structure which is specifically considered as an effective method to modify the properties of HA [10,11]."

Jan 1, 2012