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By Peter Schwartz

This paper presents GBN's "Global Scenarios" for the first decade of the 21st century. We describe a set of key scenario actors and develop 6 driving forces in demography, technology, climate change, macroeconomic change, globalization, and geopolitics. We argue that a set of majorchallenges to world systems of commerce and politics will coalesce in the next several years. We develop four scenarios which differ according to how these challenges are handled, and which scenario actors play the key roles in managing the transition.

Jan 1, 1999

By J. Miernik, D. Krupka, B. Ochab

The electrolytic zinc plant, with a capacity 75,000 tonnes per year, is part of Zaklady Gorniczo-Hutnicze BOLESLAW. It is the biggest zinc producer in Poland. The electrolytic zinc plant started up in 1955 with a capacity 15,000 tonnes per year, and multiplied its production by 5 till nowadays. At the beginning, the plant processed only calcine from zinc oxides (60% Zn, 3-4% Pb, 0,03 % Cd) which were produced from Waeltz fumes by calcination in a rotary kiln. Participation of calcine from zinc sulfide concentrates in the feed grew during the BOLESLAW plant expansion. Currently, only roasted sulphide concentrates, calcine from fluid-bed roasters, is processed. This paper presents a general description of the ZGH BOLESLAW plant and discusses the processes of roasting, leaching, purification and electrolysis. Also shown are the chemical analyses of the various process materials.

Jan 1, 2000

By Joseph J. Poveromo

Technical progress in ironmaking will be discussed in three sectors: blast furnace ironmaking, direct reduction and alternative ironmaking to feed electric arc furnaces and ironmaking for waste oxide processing. The contributions of iron ore producer, Quebec Cartier Mining, in each sector will be outlined.

Jan 1, 2006

By Robert S. Sokolowski

The future of Materials Processing in Space (MPS) in the Space Station Era is being assured today by a strong coordinated science program which looks to solve these problems, the answers to which serve to underpin the technical foundation upon which future metallurgical and materials processes will be built. The critical link between the product and process development activities that accompany this science endeavor is the "nuts and bolts" hardware that will ultimately operate in the space environment. Ground-based facilities including drop facilities and aircraft provide excellent product development and process concept study tools. Shuttle flights with Spacelab and commercially developed space facilities represent the evolutionary path to Space Station processing facilities. Today the most promising areas of MPS are crystal growth, containerless, and quasicontainerless processing. The unique features of these processes will be highlighted. Finally a more visionary perspective of MPS will be presented that incorporates the limits of today's knowledge with the economic "necessity" of tomorrow.

Jan 1, 1988

By Maria de Campos

The pre-reduction behaviour of chromite particles in methane-argon and methane-hydrogen gas mixtures was investigated between 1050°C and 1250°C. Loose bed of chromite particles were reacted in a vertical tube furnace under a pre-set gas mixture predetermined time intervals. Metallization results were obtained for the Cr and Fe components by chemically analyzing the reaction products. SEM-EDAX techniques and X-ray diffraction were employed to elucidate the reduction mechanism. It was found that higher reduction kinetics and higher Cr:Fe ratios in the metal phase would be achieved when hydrocarbon gas was used in comparison to classical carbothermic reduction at a given temperature. The reduction rate was generally bulk gas mass transfer controlled to the reaction site for initial stages which then was followed by ionic diffusion rate control. It is proposed that methane did not partake directly in the reduction but cracked, presenting the reaction site with hydrogen gas and atomic carbon, which was able to immediately react at the immediate area of reduction regeneration CO and H2 and thus maintaining a low partial pressure of oxygen at the reaction site.

Jan 1, 2006

By P. Barrios

The copper refinery of Atlantic Copper was modernised and converted to the Isa permanent cathode system in 1995. The technology installed has proved to be an excellent platform for the development of operational improvements. During the years it has been working, the progressive assimilation of the new technology has been achieved and the level of operator knowledge has allowed design production to be reached and surpassed by more than 10%. At the same time, modifications to the work programmes, using existing equipment, have permitted the incorporation of new cells and the achievement of annual production levels of 250,000 tonnes and a productivity of 0.43 t/man-hour.

Jan 1, 1999

By David B. Dreisinger

The total pressure oxidation treatment of arsenical copper ore and concentrate from the El Indio mine of Banick Gold was tested in benchtop autoclave treatment. The concentrate oxidation typically achieved ~95% copper extraction. Copper extraction was limited by the reprecipitation of a complex precipitate containing arsenic. Gold extraction by cyanidation of the oxidation residue was around 95%. Silver extractions were less than 10% due to the formation of argentojarosite in the autoclave. The total pressure oxidation of the whole ore sample was more successful. Copper extractions of 98-99% were routine achieved. Gold extraction by cyanidation was +95%. Silver extraction could be increased to as high as 95% by using the lime boil treatment. A process flowsheet was proposed based on the results achieved. Copper recovery was proposed by direct solvent extraction and electrowinning of copper by treating the dilute solution from the autoclave discharge.

Jan 1, 1999

By Antonio Luraschi

The constituents iron, oxygen, silica and cop- per are of principal interest in slags utilized in pyrornetallurgical processes for producing copper. Accordingly, phase relationships in the.Cu-Fe-0-SiO2 system are important when one considers the physico- chemical behavior of slags. These phase relation- ships for the quaternary and constituent ternary systems are developed from available information. Isothermal composition and composition-oxygen potential diagrams, and oxygen potential-temperature diagrams are utilized to describe the' important relationships.

Jan 1, 1976

By Jason Eric Sallee

Ongoing operations at the Cyprus Miami Smelter involve the use of an electric furnace for settling of copper matte from discard slag. Proper operation of the electric settling furnace is a major factor in minimizing losses of copper to the discard slag. Recent test work at the smelter has shown improvement in the operation of the electric furnace with a subsequent improvement with regard to the copper losses. This paper presents a general discussion of the Cyprus Miami Smelter operation, past results with respect to copper losses, recent operational changes and test work, and the subsequent results.

Jan 1, 1999

By Hongmin Zhu, Qiuyu Wang, Shuqiang Jiao, Guojing Hu

"The equilibrium between titanium ions and metal titanium was investigated in fluoride-chloride molten salt. The electrochemical properties of titanium ions in fluoride-chloride were studied on a molybdenum electrode by cyclic voltammetry (CV) and square wave voltammetry (SWV). The equilibrium constant of the equilibrium between titanium ions and metal Ti was calculated in KCI-NaCl- 2.5wt %K2 Tif 6 at the temperature of 1073K.IntroductionTitanium, the ninth most abundant element in the earth's crust, is endowed with high strength, low density, excellent flexibility, strong spring back characteristics, high-temperature performance, corrosion resistance and biocompatibility. These characteristics make titanium eminently suitable to be used in aerospace, marine industries, and harsh chemical environments. Although it has many excellent properties, the application of titanium in industry was limited by its high-cost. Therefore, many methods have been investigated for producing high-purity titanium at low cost. Electrolysis, involving the extraction and preparation of pure metal from ore using an electrolytic process, is considered a promising method for titanium metallurgy. Many studies have focused on the electrochemical behaviour and electrodeposition of titanium in molten chloride, fluoride, and chloride-fluoride electrolytes (1-IOJ. The electroreduction mechanism of Ti3+ ions in molten alkali chlorides has previously been studied by several workers. Two reduction steps, Ti3+ -Ti2+ -Ti, have been observed in various molten alkali chlorides [IJ. One reduction step, Ti3+ -Ti, has been observed in alkali fluoride molten salts l21. The behaviour of Ti4+ in fluoride or chloride-fluoride molten salts has also been investigated in the literature; it was proposed that the reduction of Ti4+ ions in the molten salts proceeded in a two step process: Ti4+-Ti3+-Ti l3l or a three step process: Ti4+ -Ti3+ -Ti2+-Ti ri. 4l Indeed, the stability of the titanium oxidation states depends on the bath composition l5l. The valence state was Ti2+ in alkali chloride melts, which was a lower oxidation state and correspondingly, in alkali fluoride melts, the higher oxidation states ofTi4+ and Til+ were more stable.The aim of the present work is to explore the effect of F/Cl atomic ratio on the equilibrium between titanium ions and metal titanium in fluoride-chloride at the temperature of 1073K. The electrochemical properties of titanium ions in fluoride-chloride were studied on a molybdenum electrode by cyclic voltammetry (CV) and square wave voltammetry (SWV). The solubility product of the equilibrium between titanium ions and metal Ti was calculated."

Jan 1, 2012

By Zviad Kovziridze

Structure of celsian ceramics in BaO-Al2O3-SiO2system is studied with electron microscope in the entire temperature region of baking interval. The process of the pores filling and the full consolidation of material growth at comparatively high temperatures of baking intervals are described.

Jan 1, 2006

By M. S. Moats

A considerable amount of research has been conducted to determine the causes of anode passivation. Chemical and electrochemical reactions that occur after passivation have received little attention. Chronopotentiometry, linear sweep voltammetry, cyclic voltammetry, and impedance spectroscopy have been used to elucidate three reactions that occur after passivation of commercial copper anodes. These involve the dissolution of silver and subsequent cementation and transformation of selenides, the oxidation of lead sulfate to lead oxide, and oxygen evolution. The amount of silver dissolution depends on the silver content of the anode, the time to passivation, and the molar ratio of Ag/(Se+Te). The oxidation of lead from PbSO4 to PbOx explains a potential plateau of oxygen evolution. Silver affects the duration of oxygen evolution on the PbOx. Anodes containing kupferglimmer display a characteristic oxygen evolution potential. It is believed that kupferglimmer provides a lower overpotential for oxygen evolution than the other slime phases or passivated surface.

Jan 1, 1999

By A. N. Lasseigne

Hydrogen storage capabilities of LaNi5 intermetallic compounds were investigated utilizing the combination of thermoelectric power, Beeghly Ester-Halogen digestion, and Leco hydrogen determination. Thermoelectric power has demonstrated a rapid hydrogen assessment capability and can achieve the equivalent of the pressure-composition-temperature (activity) diagram. Effective use of hydrogen storage materials occurs in the two-phase, alpha+beta region of the PCT diagram. A thorough assessment of the content of each phase in this two-phase region to optimize performance of the hydrogen storage materials is described. Practices using the combination of these three analytical practices for rapid characterization of LaNi5intermetallic alloys are discussed.

Jan 1, 2006

By Hazoor Singh Sidhu

Materials degradation due to corrosion is the major problem in power generation equipment, gas turbine, fluidized bed combustion, industrial waste incinerators etc. Some super alloys have been developed, but they are unable to have different properties to meet the demand of today?s industry. Therefore, a composite system of a base material providing the necessary mechanical strength with a protective surface layer different in structure and/or chemical composition can be an optimum choice in combining material properties. Thermal spray coating of the components before they put into service by suitable surfacing alloy and with suitable coating method can increase the life of these components several fold. Choice of right coating method and alloy for a particular application is extremely important to get the desired service life. The corrosion of some materials and the role of HVOF thermal spray coatings to counteract the same have been reviewed, with an aim to understand the phenomena along with various applications.

Jan 1, 2006

By Alex Moyano

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

Jan 1, 2006

By Toshiharu Hayashi

We prepared the water dispersed with Au particles ranging from 10 to 20 nm size by a novel wet chemical synthesis; generating seeds of Au cluster by adding a borane dimethylamine complex into chloroaureic acid (gold salt) solution, and then growing simultaneously with aminoalcohol included in the solution. As-prepared Au nano-particles with chemical surface modification were found to have some attractive performances, i.e., showing a high dispersiveness in an aqueous solution in a long time, sintering nano-particles at low temperature, and having low resistivity in the film prepared from nano-particles. In the case that smaller Au nano-particles were removed from as-prepared colloid, especially, Au thin film formed on the surface of Si plate showed the excellent value of 7.0x10-6ohm cm (reference peculiar resistance: 2.35x10-6 ohm cm).The sintering temperature was dependent on the elimination of 2-aminoethanol that modified on the surface of Au nano-particles.

Jan 1, 2006

By P. M. Pincheira Brown

The widely accepted inverse relationship between copper prices ail stocks, has been commonly used by analysts to explain the behavior of the copper market and to forecast film copper pries. However, empirical data have not shown such a clear relationship between copper prices and stacks. Existing evidence only indicates a weak tong-nut relationship that vanishes in some periods. In this paper a simple comprehensive model is provided which explains both parallel and opposite direction movements between prices and stocks. Former are explained mainly by stocks demand expansions-contractions while the latter are in essence due to increases in the supply curve. Furthermore, econometric estimations are provided, thus giving a powerful tool to forecast and explain price developments of the copper market.

Jan 1, 1999

By R. M. Donovan

This paper documents the efforts to improve quality and production at the Amarillo Copper Refinery. It summarizes the change in attitudes, work procedures, equipment maintenance, instrumentation, and the ever changing market. The Amarillo Copper Refinery is dedicated to the ASARCO Management System, ISO-9002 and continuous improvement.

Jan 1, 1999

By Ray Y. Lin

This study explores the formation of sodium pyrosulfate in molten sodium sulfate resulting from dissolution of SO3 at temperatures between 1160 and 1250 K. Solubility of SO3 in Na2SO4 melts at temperatures between 1160 and 1250 K under gas mixtures of SO2, O2 and argon was investigated applying a thermogravemetric analysis (TGA) technique. The activity of Na2O in the melt was determined with a high temperature electrochemical cell (ECC). Results showed that the SO3 solubility in molten Na2SO4 increases with decreasing temperatures and increasing SO3 partial pressures. Enthalpy of SO3 dissolution in molten Na2SO4 was calculated to be -119 kJ/mol for infinite dilute solutions. Thermochemistry of Na2SO4-Na2S2O7 melts was analyzed based on information obtained from both TGA and ECC techniques. Detailed examinations of the earlier low temperature measurements in the Na2SO4-Na2S2O7 system along with data from this study reveal that the solution behavior between Na2SO4 and Na2S2O7 can be satisfactorily treated as regular with the interaction parameter, , being 2.7 kJ/mol. The phase diagram and the field of SO3 partial pressure has been generated with the thermodynamic calculation using a regular solution approach.

Jan 1, 2006

By Nickolas J. Themelis

The role of copper in the economy will not diminish in the 21st century. Following the tenets of industrial ecology, production and use of copper must take into account both human needs and also how to minimize "collateral" effects on the environment. Dispersive uses will be phased out and post-use recovery of copper will increase. This will result into an advantage for smelting processes that can accommodate mixed metal scrap and waste streams. The bath smelting processes of Noranda and Mitsubishi will continue to make progress but the dominance of the Outokumpu flash smelting will not be challenged until the Noranda reactor overcomes the obstacles to the direct production of copper, thus eliminating the need for a converter.

Jan 1, 1999