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By Torben Edens

Norddeutsche Affinerie?s (NA?s) primary smelter continually increased production in the past decade. The smelter?s concentrate capacity was expanded from 500,000 in 1993 to 1,000,000 t/a dry concentrate in 2000 and the goal of the present upgrade is 1,150,000 t/a. These goals were reached without erecting new equipment in the anode area, but instead by refitting the existing plant. The life-span extension of the casting moulds was absolutely necessary to increase the casting performance from 260,000 to 450,000 t anodes per year on a single casting wheel. Different mould manufacturing processes and alloys were tested in order to find the optimal mould. In the past the moulds were cast directly, now the anode mould is milled into NA copper cakes. Accompanying measures taken were the shortening of maintenance and repair times as well as improvements in the refining furnace equipment.

Jan 1, 2005

By Albert Wraith, Thomas Price, Wayne Boyd, Skip (I. E. ) Hills, Cameron Harris

Most Peirce-Smith converters inject air through tuyeres, with nitrogen representing the majority of gas passing through the process. The nitrogen controls the temperature of the vessel by carrying away heat from the reactions, both globally and locally at the tuyere tip. However, nitrogen adds energy to the bath and contributes to splashing and limits the blowing rate. High oxygen smelting has made streams of gas containing high concentrations of sulphur dioxide commonplace, which can be used to substitute SO2 for nitrogen and drastically changes Peirce- Smith converting (and all other smelting/converting processes as well). Less SO2 is required to carry away the same quantity of heat, which allows higher concentrations of oxygen and leads to the possibility of increased production. The paper investigates this substitution, its impact on converter productivity, and on the remainder of the plant. 181

Jan 1, 2009

By E. I. Gedgagov, A. V. Tarasov, V. M. Paretsky, A. D. Besser

"Hydrometallurgical technology and equipment have been developed in the Gintsvetmet Institute (Moscow, Russia) for processing of rhenium-containing alloys waste to produce commercial- grade metal products with recovery of all valuable components. The technology is based on waste treatment with hydrofluoric acid with subsequent decomposition with nitric acid at pH = 1 to 1.5 to ensure maximum degree of rhenium conversion to the liquid phase of pulp. Some experimental lots of ammonium rhenate and ammonium molybdate were produced at a pilot plant. The following main techno-economic performance values have been achieved when processing grinding residues (balance-based tests were conducted with a lot of SP-2 alloy waste) to produce ammonium rhenate of high purity, as well as tantalum-niobium, nickel-cobalt and tungsten-molybdenum concentrates: rhenium recovery of 92.3% into a commercial product from grinding waste; production cost of 170-210 US Dollars per 1 kg of rhenium in commercial-grade ammonium perrhenate taking into account its recovery; tantalum and niobium recovery of 75- 77% into bulk concentrate; nickel and cobalt recovery of 88-89% into a mixed concentrate; tungsten and molybdenum recovery of 88% to 91% into concentrate. Introduction During the recent years the use of rhenium has been increasing at a fast pace worldwide [1]. The growing prices for this refractory metal are an essential factor encouraging collection and processing of rhenium-containing wastes. Double-component waste, such as molybdenum- rhenium or tungsten-rhenium alloys can be readily decomposed and the process of rhenium recovery does not cause, therefore, any difficulties. The main separation of metals takes place at the stage of waste digestion with acid, because molybdenum and especially tungsten remain in precipitate in the form of hydrated oxides and rhenium reports in the liquid phase, from which it can be easily extracted by solid ion-exchange or solvent extraction techniques. However, most of rhenium is contained in super-alloy waste [2]. Such waste has different contents of valuable components, such as tantalum, niobium, molybdenum, tungsten, cobalt, nickel, chromium and other metals. The basis of all such super-alloy waste is nickel. Refractory metals in the super- alloy composition are in the form of metallized target-oriented eutectics, and due to this reason hydrometallurgical decomposition of such alloys is a difficult technological task."

Jan 1, 2008

By P. J. Mackey

Over the course of Dr. Robertson’s career, the ferrous and non-ferrous plants have seen enormous changes in technology and increases in plant capacity, essentially amounting to a “technological revolution”. In iron and steel, the “mega” blast furnace of some 6,000 m3 working volume is now standard (~10,000 tonnes (mt) of pig iron/day). Similar huge changes in process technology and plant size have occurred in the non-ferrous industry. As an example, the fuelfired reverberatory furnace, once the mainstay of the copper industry, has disappeared - replaced by large capacity flash and bath smelting technologies. The energy consumption per unit mass of metal produced has also been reduced considerably. Our understanding of the thermodynamics and mechanisms of metallurgical reactions, a field to which Dr. Robertson has significantly contributed, has made great strides. This paper reviews these changes with particular reference to the copper smelting industry, providing also comments on expected future trends.

Jan 1, 2014

By Z. Sun, H. A. Davies

"Current understanding of the mechanisms by which glassy and crystalline thin ribbons are formed in high speed continuous casting processes is considered. A computer model of the combined heat and momentum transfer during melt spinning has been developed. The influence of roll velocity and of heat transfer coefficient (between the melt and the roll) on the temperature and velocity distributions within the melt puddle is analysed and the thickness of the extracted ribbon computed. The relative importance of heat and momentum transfer under different conditions is assessed and differences between the casting of crystalline and amorphous strip highlighted.IntroductionHigh speed continuous casting of thin metallic ribbon and strip is currently of considerable interest both to metal processers and to those studying process mechanisms. The practical interest arises both from the potential economic benefits to be gained from a shorter and more energy-efficient production route and from the ability to obtain extended and uniform thin strip having a metastable microcrystalline or amorphous structure with enhanced or unique properties. The latter arise from the rapid solidification associated with the cooling of very thin sections of melt brought into intimate thermal contact with one or two rapidly moving heat sinks.The principal processes for casting thin strip include free jet, chill-block melt-spinning (GBMS) (1), melt drag (MD) (2), planar flow casting (PFG) (3) and twin-roll casting (TRG) (4). For the first three of these, all essentially variants of melt-spinning, melt flows through a nozzle onto the circumferential surface of a rapidly rotating roll, whereas for TRG the melt passes into the nip between two contra-rotating rolls. We shall be concerned in this paper with the single-roll melt spinning processes only. For these, a puddle is established where the melt contacts the roll surface and the length of this puddle l is a function of the process conditions, notably the circumferential velocity of the roll Us and the volumetric flow rate of the melt Q. The contact time between any point on the roll surface and this puddle, or residence time eR(= l /Us) determines the thickness of ribbon t extracted from the puddle. This thickness, in turn, partly governs the cooling rate T and the amount of undercooling in the melt and thus the microstructure of the solidified ribbon."

Jan 1, 1986

By Kunihiko Takahashi, Gjergj Dodbiba, Hisayoshi Umeda, Toyohisa Fujita

"An increasing number of mobile phones is increasing the number of the discarded mobile phones. Many efforts are thus being made to collect and recycle these devices. This paper is a short introduction of the recycling system of precious metals from the discarded mobile phone, currently available in Japan. Moreover, an attempt has been made to compare the energy recovery and the mechanical recycling of plastic wastes from the discarded mobile phone. The assessment has been carried out in the context of the life cycle assessment methodology (LCA). The environmental impact of each option was assessed by calculating the following impact indicators: depletion of abiotic resources (ADP), and global warming potential (GWP). 1. Introduction In 2003, the demand for mobile phones was increased since the camera was included in a mobile phone and the 3rd generation of mobile phones was introduced. In turn, the number of discarded mobile phone is rising sharply. Generally speaking, all the metallic parts of mobile phones can be recovered and recycled by using smelting and purification techniques. The recycled materials are then used to fabricate other new products."

Jan 1, 2008

By José R. Parga

In some parts of the Comarca Lagunera with population of about 2.5 million people, situated in the central part of northern México, chronic arsenic poisoning is endemic and severe adverse effects attributed to As exposure have been reported. Lifetime exposure to arsenic will develop classical symptoms of arsenic poisoning such as skin pigmentation changes, gastrointestinal disturbances and neurological changes. There are several methods available for removal of arsenic from well water in large conventional treatment plants, however a very promising electrochemical treatment technique that does not require the addition of chemicals or regeneration is Electrocoagulation (EC). The EC operating conditions are highly dependent on the chemistry of the aqueous medium, especially conductivity and pH. In this study, Powder X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), and Transmission Mössbauer Spectroscopy (TMS) were used to characterize the solid products formed at iron electrodes during the EC process. This study will provide an introduction to the fundamental concepts of the EC method. Finally the results of this study suggest that the presence of maghemite and magnetite particles can be used to remove arsenic (III) and arsenic (V). In the field pilot plant scale study more than 99% removal of As species from groundwater is achieved.

Jan 1, 2005

By Victor Raul Alarcon

The Ilo Refinery was commissioned in 1975, with a cathode production capacity of 150,000 tpy. In 1994, Southern Perú Copper Corporation (SPCC) purchased the Refinery from Minero Perú SA. Subsequently, in November 1999, Grupo Mexico acquired control of Southern Perú. The anode production facility is located at the Ilo Refinery. A number of effective operating and quality control practices have been developed that have improved anode quality, as well as increasing anode production capacity to 350,000 tpy. These, and other optimization actions have allowed for a current density increase from 213 A/m2 to 275 A/m2, while maintaining current efficiency at 98% and sustaining the high quality of the cathode. The paper will outline the scope of operational practices in the Anode Plant and provide some discussion on the Ilo Smelter modernization project, and the resulting impact on the existing anode plant.

Jan 1, 2005

By Wolfgang Van Hooff

Encouraged by a strongly growing and evolving market for granulated products, Paul Wurth continuously improves its granulation and dewatering technologies to provide customers with state of the art installations. Continuously developed know-how about the granulation process of iron blast furnace slag enabled application to non-ferrous materials such as Ni-Slag, Pb-Slag, Blister Copper, Cu-Matte and even TiO2-Slag, which rank among the most difficult materials to granulate. This paper identifies how critical objectives in granulation and dewatering technologies applied to different molten materials with respect to various product quality objectives can be addressed. The differences between hot and cold water granulation systems are explained, including the step from cold runner to granulation water tank. Development of a flow and pressure controlled blowing box is the latest step to optimize the granulation process in order to meet the latest standards in terms of quality, power consumption and environmental protection.

Jan 1, 2006

By Sven Reutzel

Investigations show that Co-based melts embedded by glass flux in a crucible can be under- cooled nearly as strong as samples processed containerlessly by electromagnetic levitation. This allows to measure magnetic susceptibility on undercooled melts while combining the use of a Faraday-balance and undercooling technique. The magnetic susceptibility of Co and Co-based alloys (such as Co-Pd and Co-Cu) is investigated as a function of temperature from superheated to undercooled state. This is done by measuring the change of magnetic force F, on a sample in a constant magnetic field Bo and an additional gradient field by means of a Faraday-balance. When liquid Co-based alloys are undercooled the magnetisation steeply rises if temperature approaches the Curie temperature. The magnetisation is measured for some Co-based alloys in liquid state as a function of alloy system and its concentration. The results show that the magnetic susceptibility of the liquid undercooled samples follows a Curie-Weiss behaviour, from which Curie temperature and magnetic moments for the liquid state are inferred.

Jan 1, 2002

By Xiaodong Wang

A liquid metal flow generated by a magnetic field whose traveling direction is periodically reversed, the Reversed Traveling Magnetic Field (R-TMF) is studied. The modulation frequency ranges from 0 to 6 Hz. Ultrasonic Doppler velocimetry probes the generated fluid flow. Depending on the modulation frequency, a number of characteristic flow features are exhibited. A transition frequency (approximately 4 Hz) exists, above which the flow is no longer sensitive to the force modulation. Below this transition point, the amplitude of the velocity oscillation increases, and then below fm = 0.05 Hz, it saturates around a value close to that observed without any modulation. A theoretical model to obtain an analytical solution of electromagnetic force and to predict flow motion is developed, which is fairly in agreement with the experiments.

Jan 1, 2009

By Dale A. Zuck

Recovery of aluminum metal from drosses? is a major factor in the recyclability success story enjoyed by the United States aluminum industry. Today's modern dross processor uses the latest technology to maximize metal recovery at the lowest cost while complying with all environmental laws and regulations. Most dross processors, however, pay little attention to the resulting saltcake, the end residual of dross recyCling, and rely on landfills for .disposition of this material.. The alternative is to recycle the saltcake, but the success of this technology is dependent on the development of reliable outlets for each of the saltcake constituents. This paper discusses the evolution of an aluminum dross oxide processing technology that ,produces an economically attractive source of alumina for the production of portland cement.

Jan 1, 1995

By Bo Björkman

A controlled dust generation whereby the dust generated would be enriched with specific metals would considerably facilitate the possibilities of recovering metals from such dusts. A basic understanding of the dust forming mechanisms is of fundamental importance to achieve a controlled dust generation. The present study deals with dust formation in a copper converting process. Dust samples collected from various places in the gas cleaning system were characterised for chemical and mineralogical composition using chemical analysis as well as microprobe analysis. Thermodynamic calculations were used to predict the formation of chemically formed dust at various temperatures and amounts of leakage air to the gas system. The results show that a separation of mechanically formed dust. e.g . Si0:2. Cu and chemically formed dust. e.g .? Ph, Zn, As, Bi. could, to some extent, be obtained due to their different particle sizes. A selective condensation of Pb, Zn and As at various temperatures could. according to thermodynamic calculations, he possible at high temperature. A selective condensation of metals requires an airtight gas cleaning system or a gas cleaning system with a limited amount of leakage air in order to maintain the desired temperature level.

Jan 1, 1996

By David G. Dixon, Maziar Eghbalnia

"Gold and silver nanoparticles (NPs) were deposited on pyrite at ambient temperature from colloidal solutions prepared by reduction of hydrogen tetrachloroaurate or silver nitrate by sodium sulfide or sodium tetrahydridoborate. The nanoparticles were characterized using Ultraviolet-Visible (UV-Vis) spectroscopy and the experimental spectra were fitted using Mie - Gans modeling. The modified pyrite was investigated using Electrochemical Impedance Spectroscopy (EIS). Electrodes were prepared from both natural and modified pyrite samples and were modeled using an equivalent circuit (EC) based on the EIS data. The comparison of the results revealed a decrease in charge transfer resistance for the ferric ferrous redox couple associated with the modified pyrite. From this behavior it is concluded that the electronic transport between the nanoparticles and the electrode surface over distances in nanometer scale is enhanced. Nanoparticles below a certain size act as quantum dots due to electronic confmement. Decreased charged transfer resistance at the nanometer scale may be caused by electron transport through tunneling mechanism via quantum dots.IntroductionIn recent years, considerable attention has been focused on the synthesis and study of Metal nanoparticles due to their potential applications in the fields of physics, chemistry, biology, medicine, material science and their interdisciplinary fields[!]. When material is nano-sized, the physical properties deviate markedly from those of bulk material, however, this effect is highly dependent on the particle size, interparticle distance, and morphology of the nanoparticles [2].An extremely small region of space defmed in a semiconductor material in order of nanometers is called a quantum dot, a term coined by Reed [3]. The three dimensional confinement of quantum dots can change properties of the excitons in comparison to free excitons in a bulk material [4]. Nanoparticles behave electronically as zero-dimensional (restricted in all three dimensions) quantum dots when the de Broglie wavelength of the valence electrons and the particle are in the same size range.As Reed [3] explains electrons confined in a plane have no freedom to move the third dimension. Those confined in a quantum wire are only free to move in one dimension, and those confined in a quantum dot are not free in to move in any dimension. An electron inside a cube of material IO nm on a side is confined to a point."

Jan 1, 2012

By Jukka Tuominen

The history of making blister copper in an Outokumpu Flash Smelting Furnace dates back to the late 1960?s, when Outokumpu first piloted the Outokumpu Direct Blister (ODB) process. The first commercial scale applications have been in use at Glogow, Poland, since 1978 and at Olympic Dam, Australia, since 1988. These applications utilize special concentrates, which are low in iron, and thus the formation of slag is also low. In 1995 the same principle was applied to smelting copper matte into blister copper in industrial scale at Kennecott Utah Copper. This application, the Kennecott-Outokumpu Flash Converting process, will celebrate its 10th anniversary of commercial scale operation this year. This paper outlines the development in efficiency and flexibility of Blister Flash Smelting processes compared to other smelting and converting options. The focus is on the economical aspects i.e. on the total feasibility of both greenfield investment projects and revamping of existing smelters.

Jan 1, 2005

By María Eugenia Castro, Silvia Galasso, Jorge Duca, Claudia Osuna, Ernesto Esparza

"We present a procedure for treatment of non-active solutions equivalent to the solutions obtained from dissolution of ionic exchange resins used in purification of a nuclear reactor primary cooling system containing Co, Ni, Cs and its isotropic varieties as main radioactivity source. Finally it is immobilized into a ferritic matrix by calcination which avoids its future leaching into environment.In order to achieve the objective of this treatment, a bivalent and a trivalent iron salt is added to the solution. Then, either a base or an acid is added, depending on the initial pH of the treated solution, with a Cs precipitating additive in order to reduce Co and Cs by precipitation, flocculation and adsorption. Controlling the amount of precipitating reactives it is possible to modify the activity/volume rate becoming a medium into a low radioactivity waste.The leaching test result applied over the ferritic sample is lower than the minimum limit established by law. Therefore, it can be kept safely in a interim storage."

Jan 1, 2008

By Thomas Weyand, Thomas Claridge, Dale Nickels

"This paper addresses the initial results of a project to evaluate the suitability of copper mining tailings as raw material for the production of structural products using PMET’s patented technology. Preliminary testing indicated that high performance structural products were possible using these materials. A demonstration scale project produced approximately 1,500 bricks in various colors. These products fall under under ASTM C- 73 and were found to present properties suitable for severe weather applications. Although the products in this project were of typical brick dimensions, other products are possible, for example concrete block substitutes or pavers. These products from the PMET process are commercially known as Brixx. This paper will provide operational details of the production process, mineralogy and mechanical properties of the products.INTRODUCTIONPMET has developed process technology that can convert various siliceous waste materials into competent structural products. This technology is the subject of US patent # 6,068,803. In general, the process consists of mixing lime, water and the major feed stock, pressing to form a “green” shape, and curing the product in an autoclave for 6 hours with saturated steam at ~200oC. The curing process forms Tobermorite, which acts as a crystalline binder. Freeport-McMoRan approached PMET to see whether mine tailings from the Sierrita mine, containing significant amounts of clay, might be a suitable feed material for the production of structural products. “Brixx” is the commercial term used to describe the resultant structural product formed in the test work. This paper is a preliminary evaluation of a technology that is being considered by Freeport-McMoRan. This report is not an endorsement by Freeport-McMoRan of the process or products, nor is it a commitment to use this technology."

Jan 1, 2008

By Philip Arthur

The ISASMELT process is making a significant contribution to the global metals industry. ISASMELT furnaces are now operating successfully in eight different countries and treating approximately 3 million tonnes of concentrates and secondary materials per year. The process is currently used in both lead and copper smelting. The most recently commissioned plants were in Germany and China, one for treating scrap copper and the other treating low-grade copper concentrates. The Copper ISASMEL T furnace ("CIF") at Mount Isa Mines Limited (UMIM") has continued to set new operational records, with throughput of more than I million tonnes of concentrate per year and very low operating costs. This paper summarises the latest operational data from the Mount Isa Copper ISASMEL T plant and outlines the successful approach to industrial R&D taken by MIM in the development of the ISASMEL T process.

Jan 1, 2003

By Philip Arthur

The ISASMELT process is making a significant contribution to the global metals industry. ISASMELT furnaces are now operating successfully in eight different countries and treating approximately 3 million tonnes of concentrates and secondary materials per year. The process is currently used in both lead and copper smelting. The most recently commissioned plants were in Germany and China, one for treating scrap copper and the other treating low-grade copper concentrates. The Copper ISASMEL T furnace ("CIF") at Mount Isa Mines Limited ("MIM") has continued to set new operational records, with throughput of more than I million tonnes of concentrate per year and very low operating costs. This paper summarises the latest operational data from the Mount Isa Copper ISASMELT plant and outlines the successful approach to industrial R&D taken by MIM in the development of the ISASMEL T process.

Jan 1, 2003

By R. M. Sweetin

Detailed descriptions by operating area of the Kidd copper smelter are presented, together with accounts of complement staffing, training, and preparation activities for smelter start-up in June 1981. Concentrate tonnages smelted in the first twelve months of operation were constrained by the capacity of the furnace off-gas system. However, modifications designed and introduced over that period, plus sustained efforts by operations and maintenance personnel have resulted in stepwise improvements in smelter performance.. Consistent operation at design feed rates has been well demonstrated over the third and fourth smelter campaigns and efforts continue on further improving the continuous smelter on-line times and increasing campaign life. In November 1982., following a seventeen month preproduction period, the Kidd smelter attained full operating status.

Jan 1, 1983