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By Jing Zhan, Gui Li, Wei-feng Li, Li-Hua Jiang, Chuan-fu Zhang, Jian-yang Hwang

Thermodynamics analysis for processing the charge with lead concentrate and lead sulfate-containing materials in bottom blowing smelting furnace was conducted. The results show that the technology of large-scale processing PbSO4- containing materials with PbS concentrate in bottom blowing furnace under the condition of using high-iron slag type, batch heat supplement, high temperature and rich oxygen is thermodynamically feasible. The exploration test and industrial experiment confirm the results. When S content in mixed ore is 16~17% with coke foam content of about 5%, the lead paste amount can be increased up to 40%.

Jan 1, 2015

By Guolin Zheng, Tiejun Chun, Jian Pan, Deqing Zhu, Xianlin Zhou, Dong Chen

"The high temperature oxidizing-chloridizing roasting is one of useful methods to separate nonferrous metals from pyrite cinder and metallurgy slag. However, as one kind of main nonferrous metals in pyrite cinder and metallurgy slag, copper’s chlorination behavior is not demonstrated. In the present study, chlorination behaviors of CuO, Cu2O and CuS at the temperature range of 1025-1175 ? in air by simulating the chloridizing roasting process of pyrite cinder and metallurgy slag have been investigated. It is shown that Cu2O and CuS is much easier to remove, CuO is refractory to remove. In addition, the presence of SiO2 and CaO increases the Cu removal rate from CuO while the presence of SiO2, Al2O3, CaO and MgO decreases the Cu removal rate from Cu2O. Fe3O4 influences the Cu removal rate from CuO and Cu2O positively.IntroductionAs two kinds of significant secondary resources, pyrite cinder and metallurgy slag contain not only abundant iron but also considerable copper, lead, zinc etc. Millions of tons of pyrite cinder and metallurgy slag were discharged from nonferrous metal and chemical industries annually [1, 2] in China. The pyrite cinder and metallurgy slag are formed by roasting of minerals at a high temperature, so the properties of them are distinctly different from the natural iron ores, and the iron in them is closely associated with copper, lead, zinc and other nonferrous metals. High-quality pyrite cinder and metallurgy slag containing high iron and low impurities can hardly be obtained, leading to their low utilization degree [3]. Chlorination is characterized by the high reactivity of chloridion, the high volatility and low melting point of metal chlorides, and the big differences in the formation of metal chloride. Therefore, chlorination is widely applied in extraction metallurgy."

Jan 1, 2012

By H. Hirayama, T. Okura, O. Kato

"Saganoseki Smelter & Refinery, one of the largest copper smelters in the world, has the annual capacity of 300,000 metric tons in copper content with two flash furnaces, six Pierce-Smith type converters, two anode furnaces, four acid plants, three tank houses and perfect pollution control system.Coping with the many severe conditions surrounding the copper industry in the last decade, Saganoseki Smelter has kept performing the stable operation, while enhancing the smelting capacity and developing new technologies such as the hydrometallurgical treating of converter dust recovered at electric precipitators. Especially in the operation of flash furnaces, which are of Nippon Mining's conversion type using hot air in a temperature of l,000ºC some technological improvements and complete operation control factors have approved the concentrate feed rate to reach to 2,200 tons a day for a flash furnace.Reported in this paper are the production control design for copper smelting process, and the operation control scheme of the flash furnace following the brief review of the characteristic of Saganoseki Smelter's process and some improvements. Copper Smelting ProcessDescriptions of major unit operations and general specifications of the copper smelting facilities are summarized in Table 1, and the present flowsheet of the copper smelting is described in Figure 1 (1,2).Outputs and raw materials treated in the last five years are shown in Table 2, in which concentrate includes powder copper scrap which amounts to 3 to 4% of concentrate.A full operation was performed for a period of one month, for both one flash furnace operation and for two flash furnace operation. With one furnace operation, 19,200 tons of copper were produced. With the two furnace operation, 84,000 tons of concentrates were charged and 33,500 tons of anode (net 28,600 tons of copper) were produced.The actual production level, however, has been kept at 80 to 90% of the full capacity because of low copper price, tight market of copper concentrate or fall of net demand in Japan."

Jan 1, 1989

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 V. A. Bryukvin

A characteristic feature of the macrokinetics of the interaction process is the presence of two specifically defined areas of oxidation which had a linear time dependence. The effect of variables, such as residual sulphur content of the melt, temperature and the oxidation potential of the gas phase, on the macrokinetics of oxidation are investigated. Phase composition and structure of products of solidification of partially oxidised melts and thermodynamic properties pentaining to Cu-S-O melts are used to analyze the macrokinetic behaviour and mechanisms of the interaction. The process of interaction of sulfide copper melts with oxygen may be considered as a disproportional absorption process and its mechanism is based on localized interaction on the surface and inside the melt volume. Superficial processes include also the process of primary chemisorption of oxygen by melts at place of metal-metal donor bonds proceeding with formation of oxysulfide liquid solutions and volumetric decomposition of the latter accompanied by evolution of sulfur dioxide and metallization of sulfide melts. It is the degree of dynamic balance of such interaction processes that determines specific individual features of the macro-kinetics and mechanism of oxidation of sulfide copper solutions with oxygen in the gas phase.

Jan 1, 2006

By Guray Kaya

Boron minerals are widely employed in various fields such as ceramic, glass, cement, metallurgy, etc. Although boron deposits of the world are limited, the production level of boron-based products is continuously increased. Turkiye possesses approximately 73 % of total world boron resources. Etibor Kirka Borax Company of Turkiye produces tincal concentrates and borax pentahydrates. During such productions considerable amounts of concentration and derivation wastes appear. Having considered the increased rate of production it is quite obvious that the level of relevant wastes will also be raised. With this study it was aimed to utilize these wastes in roof tile and brick bodies and to convert them into a form environmentally and human friendly. Newly produced products were undergone to several standard tests for the determination of their shrinkage, water absorption, strength values and coloring parameters. Additionally, micro structural studies were conducted.

Jan 1, 2006

By T. V. Jayaraman

Fe-Ga alloys, with compositions around 27.5 at % Ga, can be heat treated to obtain ? (ordered bcc), DO19 (ordered hexagonal), and L12 (ordered fcc) ordered structures. Our earlier work using polycrystalline samples had shown that magnetostriction is strongly influenced by ordering in this alloy. Here more detailed study of the correlation between ordering and magnetostriction using single crystals of Fe 27.5 at. % Ga alloys is reported. Single crystals of Fe 27.5 at % Ga were grown using Bridgman single crystal growth technique. X-ray and electron diffraction were used to study the ordering in this alloy. Magnetostriction measurements were carried out at no load conditions. Elastic constants were measured using Resonant Ultrasound Spectroscopy.

Jan 1, 2006

By Joel K. Witt

San Manuel Oxide operations of BHP Copper, located in Southeastern Arizona, operates a leach-solvent extraction/electrowinning (SXEW) facility that produces high quality cathode copper from low-grade oxide ores. Permanent heap leaching and in-situ leaching methods accomplish the dissolution of copper from the oxide ores. Open pit mining and heap leach construction took place from 1985 to 1995. Run-of-mine oxide ore from the pit was hauled to the heap dumps and leached by the soaking cure and continuous irrigation method. Solution application to the heaps still continues and acid soluble copper recovery has reached 86%. This paper presents and discusses the current operating practices and innovations applied to the leach facilities to maximize copper recovery from the heap leached residue. Factors such as irrigation methods, solution chemistry, sideslope treatment, post curing, lixiviant acid strength, and "rice paddies" irrigation, will be discussed. Heap leach solution control and sampling methodologies will be also presented.

Jan 1, 1999

By Pekka Taskine

In the Kokkola zinc smelter, as in most other zinc roasting plants, there is now a trend towards using concentrates with an increasing impurity content. This also often means that the size distribution of the concentrates gets finer. Iron is present in sulfidic zinc concentrates with the highest percentage as a single impurity. The behavior of iron in zinc roasting was studied in laboratory experiments. Commercial zinc concentrates with a low and high (1.5 - 16 wt-%) iron content as pyrite or in the sphalerite lattice were oxidized to various degrees to establish the reaction mechanisms of iron in roasting. Microscopy studies were carried out on the calcine, and the findings were presented in numerous photographs of the polished cross sections. SEM/EDS techniques were used for analyzing the phases and particle morphologies present in the samples. An oxidation mechanism of zinc concentrates with a high iron content was suggested.

Jan 1, 2002

By Torben L. Edens

Norddeutsche Affinerie is the largest copper producer in Europe. Two sites are in operation for the production of refined copper: primary copper production is located in Hamburg and secondary copper production in Lünen. A total of just under 560,000 tonnes of copper cathodes is produced annually at the two sites. Primary copper production using the flash smelter furnace has been in operation in Hamburg since 1972. Over the years, the capacity of the flash smelter has been increased in three expansion projects from 120,000 t to almost 500,000 t of anode copper p.a. The anode sector consisting of two anode furnaces and a 24 mould casting wheel still features just about the same equipment as in 1972. The paper describes the most important steps taken to optimise operation which have put NA in a position to cast meanwhile more than 500,000 t of anode copper annually with the two anode furnaces and 24 mould anode casting wheel.

Jan 1, 2006

By P. S. Arthur

The ISASMELT? process is a submerged lance smelting technology operating in smelters in Australia, the USA, Belgium, India, Germany, Malaysia and China. Further plants are under construction in Peru and Zambia. Following the invention of the Sirosmelt lance technology Mount Isa Mines recognised the commercial potential in the novel top blown bath smelting process and embarked on a development program that has lasted more than 25 years. After successful operation of pilot plants and demonstration plants producing copper and lead, Mount Isa Mines decided to license the technology to external companies. Since the purchase of Mount Isa Mines by Xstrata in 2003, Xstrata Technology has assumed responsibility for transferring the technology to ISASMELT? licensees. In the 15 years since the first commercial furnaces started operation plants have been constructed (or are under construction) with a combined annual smelting capacity of more than six million tonnes of concentrates or secondary raw materials. Process development continues on the commercial scale plants at Mount Isa and elsewhere. Many of the improvements implemented by plant operators have been passed on to, and adopted by, other licensees. Exchange of ideas and technical improvements occurs through ad hoc visits to fellow licensee sites and through regular licensee workshops arranged by Xstrata Technology. This paper updates the reader on the status of various ISASMELT? plants either operating or under construction. It highlights the important role that the technology provider?s operational experience plays in ensuring that new smelting plants ramp up quickly to nameplate capacity.

Jan 1, 2006

By D. Quattrini

The aim of the present work is to present the gas chromatography (GC) as an alternative method of analysis in the thermal decomposition of calcium carbonate. Therefore, a furnace/GC on-line system was employed to study the kinetics of the reaction, measuring the CO2 produced in the decomposition. One of the advantages of the GC method is the possibility to perform an in-situ characterization and quantification of the gaseous products to obtain kinetic parameters, besides the method is simple and shows a good reproducibility. The decomposition of calcium carbonate was carried out in isothermal conditions at temperatures from 655 to 715°C with nitrogen as purge gas. Several gas velocities were used to determine the adequate flow that minimizes the effect of external mass diffusion as rate controlling step. It was made a preliminary analysis of the sample size influence on the reaction rate. The activation energy of the reaction was determined by Flynn method. The value obtained was in a good agreement with other authors. On the other hand, gravimetric measurements were employed for compare GC results.

Jan 1, 2006

By Jin Liu

To improve value metals recovery, a new operating concept for the Inco flash furnace was investigated, in which the flash furnace coke addition practice would aim at establishing a reducing barrier on the surface of the molten bath. The descending partially oxidized sulfide mineral particles would reach the supernatant coke layer prior to the formation of slag. The key for success depends on the effectiveness of the coke layer to produce a sulfur deficient matte while maintaining furnace production capacity. The mechanism and rate of carbon reduction of the phases formed in the flash flame, i.e. sulfide (matte) and oxysulfide was investigated by means of crucible graphite reduction test work. The objective of these tests was to measure the rate of solid graphite reduction of matte, oxysulfide, slag, and matte+slag mixture at different temperatures. These tests were expected to permit understanding and explaining the reduction mechanism of each material by comparing the respective reaction rates, product reaction gas compositions, reduced material assays, and other relevant parameters. Direct visual inspection of the test crucibles would provide additional information.

Jan 1, 2006

By Takashi Yoshida

"This paper will discuss the recent situation and future of the zinc industry from the technical point of view. It includes recent problems faced by the zinc industry and technological developments. One of the biggest problems of the zinc industry is raw materials. Traditional zinc concentrate becomes much complicated with respect to its chemical and physical properties. Thus, each process faced various problems. Also, secondary resources, generating so called recycling processes, become much more important. Recycling is, of course, a very important aspect for sustainable development of society. Secondary raw material also includes a great variety of impurities not included or very low levels in traditional zinc concentrate. Some problems are caused by these impurities. To overcome these problems some technological challenges have been taking place. Details will be discussed in the symposium.IntroductionZinc is a very useful metal based on its elechtro-chemical, chemical and physical properties. The most important usage is galvernizing of steel which is used for automobile, construction and a very wide range of other indutries. Also, zinc is used for dicasting and other alloys such as brass. Smelting of zinc is different from other metal because of its electro-chemical properties. Many parameters should be controled compared with other metals such as iron and copper. Typical zinc smelting processes are the Imperial Smelting Process (ISP) and the electlolytic process. The ISP process is a pyro-metallurgical process using a blast furnace. The electrolytic process is a hydrometallurgical process. Both processes are energy intensive, and the smelting process cost is increasing because of higher energy costs. The situation of the ISP is very severe because of higher coke prices. Recently, many ISP plants have been shut down because of economic reasons"

Jan 1, 2012

By D. I. Chalmers

The Brockman rare-metals and rare earth resource is located within volcanic and volcanogenic sediments of the later Proterozoic Halls Creek Group in the East Kimberley region of Western Australia. Exploration including surface trenching, percussion and diamond drilling has defined a major resource of rare-metals and heavy rare earth elements. The host&apos; is a steeply dipping ash-flow tuff, described informally as the Niobium Tuff, enriched in zirconium, hafnium, yttrium, niobium, tantalum, rare earth elements, gallium and beryllium. The mineralization is fine- grained (<20 micrometres) and is the result of alteration and re- mobilization of comparatively simple precursor minerals such as columbite and zircon by fluorine-rich deuteric solutions that were retained in the tuff following eruption. The ultra fine-grained structure of the tuff precludes mineral liberation and separation by physical methods. However, values can be converted to water soluble sulphates by reacting with concentrated sulphuric acid at 250°C. The solution containing aluminium, niobium, tantalum, zirconium, hafnium, yttrium, rare earths and gallium can then be processed to pure products in a sequence of solvent extraction and ion-exchange steps. As a result of these processing techniques, the commercial products obtainable from the resource include mixed rare earth and yttrium concentrates, zirconium-hafnium concentrate, niobium-tantalum concentrate and ceramic grade alumina. Further separation could result in high purity products suitable for ceramic and electronic applications.

Jan 1, 1992

By M. Rosales

By a physical and mathematical modeling, the behavior of the tri-dimensional waving, and the movement of the gases at the Teniente Converter was studied. The mathematical model considers the condensed phases of white metal and slag, along the gas phase, and includes the k-e model for the turbulence description. Both the physical model and the mathematical model allow to conclude that from a fluidynamic stand point the Teniente Converter clearly can melt 3000 tpd of concentrates. Also, both models are suitable to predict the slag fluidynamics and its spacial distribution inside the Teniente Converter, and the splashing in the tuyere zone as well.

Jan 1, 2006

By L. Béjar-Gómez

The aim of this research work is to study and characterize the precipitates in structural microalloyed steel by transmission electron microscopy and analysis by low resolution. Microalloyed steel with niobium was produced by casting in an electrical induction oven of 25 Kg capacity. Carbon content in steel was less than 0.1 % and 0.036% of niobium. Steel was processed thermomechanically; reheated to 1250 °C and hot rolled on a laboratory mill to a 13.0 mm thick plate with a finish rolling temperature of 900ºC and a thickness reduction of 80% . This work shows what precipitates are present in steel, the type of precipitates and their morphology. Analysis by transmission electron microscopy of low resolution was applied to obtain the chemical analysis of precipitates and the matrix. Spectroscopy of dispersive energy (STEM - EDS) was applied to obtain the element profile of precipitates. Particles of precipitates of NbC were found; with cubic morphology and size from 70 to 130 nm, circular morphology and size from 10 to 70 nm, polygonal morphology and size from 10 to 80 nm.

Jan 1, 2006

By Mitsuru Tanahashi

Oxidation removal of boron from molten silicon by injecting oxygen and highly basic CaO-CaF2flux powder has been investigated with special attention to the dynamic behavior of the injected flux particles and gas bubbles. Since oxygen gas is injected into the melt, high oxygen partial pressure is maintained at the flux-O2-Si interface and the removal of boron proceeds under nonequilibrium conditions. By applying this process, boron concentration in metallurgical-grade silicon can be reduced to a single-ppm level. In this paper, the effects of the dynamic behavior of the flux particles injected into the silicon melt and the area of the reaction field (the flux-O2-Siinterface) formed in the vicinity of the flux-gas exit of the injection nozzle on the rate of the boron removal are discussed from the viewpoint of process dynamics. The experimental results clarified that the boron removal rate is affected by the kinetic energy of the flux particles which is determined by the injection conditions, such as the gas-flow rate of oxygen and the size of the flux particles. At higher oxygen gas-flow rates, the injected flux particles are expected to possess a significantly high kinetic energy such that they penetrate the O2-Si interface formed at the nozzle exit, which results in the formation of a new reaction field for boron removal. On the other hand, at lower gas-flow rates, the injected flux particles possess too low kinetic energy to penetrate the interface. In this case where the formation of the reaction field is limited, it is shown experimentally that the rate of the boron removal is constant, independently of the flux injection rate.

Jan 1, 2006

By Daniel Kittelty

A fully instrumented laboratory electrowinning cell has been used to produce nickel cathodes from synthetic solutions containing various impurities in order to evaluate the effects of both metallic ions and organic reagents (from prior solvent extraction and other processes) on the quality of the electrodeposited nickel. The conditions used were typical of those employed in industrial electrowinning operations. The impurities were found to alter the crystal size and shape, induce the development of hydrogen pits on the deposit surface, incorporate as metal hydroxide crystals in the deposit, and alter the internal stress and current efficiency. These effects have been interpreted in terms of previously established relationships between the solution composition and the physical properties of the cathodes. The incorporation of the common metal impurity ions into the deposit have been interpreted in terms of a mass transport controlled reduction or precipitation reactions. In particular, a low concentration of aluminium ions resulted in an initial highly deleterious effect, which was replaced by a positive influence at higher concentrations. A model which involves the buffering effect of the aluminium on the pH at the cathode surface has been proposed.

Jan 1, 2003

By Takahiko Okura, Satoshi Okano, Hiromichi Takebe

"Fine zinc concentrates tend to become sticky when roasted in a fluidized-bed reactor. The oxidation of high-purity ZnS powders and ZnS concentrates with different particle sizes were studied in terms of phase changes and particle morphologies. The sample materials were directly oxidized to ZnO in a roasting process performed over 700°C. Zinc oxide particles with diameters less than 0.5 ìðé formed at 700°C; the particle size increased by grain growth at 900°C. The coarse ZnS concentrate formed the oxysulfate ZnO2ZnS04 when roasted at 700°C; the sulfate transformed to ZnO at higher temperature.1. IntroductionRoasting is an important step in zinc extractive metallurgy because more than 80% of the world's zinc is produced from zinc sulfide concentrates using the roast-leach-electrowinning [1,2]. Currently, zinc concentrates with a finer particle size distribution are used to enhance recovery rate. However, the finer zinc concentrates tend to produce a sticky calcine in a fluidized-bed roaster [3].The factors that affect products in a fluidized-bed roaster include particle size, contaminant, O2 and SO2 partial pressures, and the feeding method of ore to the roaster. This study examined roasting behavior of high-purity ZnS powders and ZnS concentrates with different particle sizes. The phase changes and particle morphologies of the calcine samples producted from theZnS powders were studied."

Jan 1, 2012