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By André L. B. Bittencourt

The copper content in the waste slag represents the greatest loss in the process of Caraíba Metais' Smelter. By identifying the variables responsible for copper stabilization in the slag, a minimization on these losses is expected, producing a granulated waste slag with a copper content lower than 0.7%. Statistics resourses such as control charts, Pareto's diagram and correlations curves were applied for the data obtained in the first semester of 1992. The magnetite and the calcium oxide contents in the slag of the Flash Smelter Furnace were most prominent variables. Some operational changes introduced during and after this investigation have shown good results.

Jan 1, 1994

Equilibrium calculational software programs can be effectively utilized to illustrate the importance of activity or concentration, solubility, temperature, solution pH, solution potential, and ligand complexation to students studying hydrometallurgy. The calculational program STABCAL will be demonstrated. illustrative examples for the creation of diagrams such as EH-pH, activity or concentration-pH and activity or concentration-EH will be presented to demonstrate the fundamentals of real hydrometallurgical systems. Speciation, titration and mixing will be used to simulate or predict operational processes. Applications will include treatment of Acid Mine Drainage (Berkeley Pitlake water and sediments), mass balance potential/pH diagrams, leaching and selective separation of metals from electroplating sludge, metal adsorption at femhydrite surfaces, and flowsheet development for treating mercury sulfide K106 sludge.

Jan 1, 2002

By Florian Kongoli

Non-ferrous smelting slags .can contain magnesia, which substantially increases the liquidus temperature. One option to counter this increase is to flux with calcia. In this work, experimental liquidus measurements including new measurements on industrial slags have been compared with a FACT-based thermodynamic model, which predicts the liquidus surface of multi-component iron silicate smelting slags containing both magnesia and calcia. The predictions, which agree well with experimental results, are summarized in both isothermal and non-isothermal diagrams to give a quantitative description of the liquidus surface.

Jan 1, 1998

By Xiangwen Wang

Electrochemical measurements associated with the electrowinning of lead metal from concentrated brine (NaCI) - lead chloride (PbCI,) electrolytes at temperatures in the range 328 to 353°K (55 - 80°C) were conducted. The electrodeposition of lead metal onto a lead rotating-disk electrode may be described by the electrodic reaction: {PbCl 4 2 + 2e- = Pb° + 4Cl-} The deposition-overpotential requirements are low (approximately 41mV per decade of current density - Am+), with a corresponding high exchange current (approximately 0.018 A.cm2). The diffusion coefficient of the electroactive PbC142- species in a 3.5 NaCl electrolyte at 353°K was insensitive to the total PbCI, concentration (0.01 to 0.1M), and its value was found to be (1.21*0.1)~10-5 cm2Is with a temperature-sensitivity coefficient (E,/R) of approximately 1.98x103K-1 (328OK(T<353OK).

Jan 1, 1993

By Carl C. Nesbitt

A process has been developed to recover and recycle metals from wastes of brass foundries which contain copper, zinc and lead in various quantities. Tests were conducted to evaluate several leachants, including sulfuric acid, ammonia, hydrochloric acid, cyanide and acetic acid, and to determine the optimum leaching conditions, such as air flow rate, initial copper ion concentration, temperature, and agitation strength. Sulfuric acid containing copper sulfate with dissolved oxygen is the most successful leachant. More than 99% of the copper and zinc originally present in the waste was dissolved, while only 0.5% of the lead entered the solution after 14 hours of leaching. The leaching mechanisms of copper, zinc, and lead are proposed. The copper and zinc can be recovered from the solution by electrolytic processing. The unleached residue may be converted to a lead carbonate which can be converted to litharge at 400-450°C and to massicot at temperature above 500°C by calcination.

Jan 1, 1995

By Willy Persson

A common feature of the kinds and amounts of impurities present most pyrometallurgical, processes is injection of oxygen to, remove various in the feed. The degree of success of a specific process step relies critically on control of the instantaneous oxygen potential/oxidation stage, throughout the step as well as upon termination of the step. This will, for instance, determine the distribution of impurities between metal and slag. As long as the operation is perturbation free -detailed analysis of all additions and application of advanced models often yield satisfactory control means However, a pyrometallurgical process is seldom free from disturbances, which reduces the accuracy of the static models and leads to inconsistencies in scheduled route might be uncontrollable changes in quality and quantity of feed, operator interventions and shift changes, timing of cranes, lining wear and accretions etc. The implementation of dynamic, control to correct for disturbances and, more generally for process optimization, requires continuous on-line information on, the actual status of the process. The implementation of sensors for continuous process monitoring, e.g., as regards the instantaneously prevailing oxygen potential or oxidation stage, has been hampered by the highly aggressive environment in smelters; This is. where remote-sensing techniques based on optics and spectroscopy, have proven to form invaluable, tools towards the realization of dynamic production control. Since about 15 years Semtch has developed and industrialized a remote-sensing technology, based on ,optics and spectroscopy, for continuous on-line process monitoring and production control of various pyrometallurgical processes. The presentation will discuss applicability aspects with examples and experiences from installations and tests in ferrous and non-ferrous industry. Keywords: Applied spectroscopy, Metallurgy, Process monitoring, Production. Control

Jan 1, 2003

By N. Kanari

Chalcopyrite concentrates and their pure constituents were chlorinated by C12+N2 between 25 °C and 750 °C. The reaction products were analyzed by SEM, XRD and chemical analysis. The effect of gas flow rate and chlorine content of the gas mixture on the reaction rate were investigated. At room temperature, these solids start to react with chlorine giving metal and sulfur chlorides. Complete reaction is achieved at about 300 °C and the iron and sulfur chlorides were fully volatilized. The chlorination residue is composed of valuable metals&apos; chlorides. A simplified flow - sheet for the treatment of chalcopyrite concentrates by chlorine was suggested.

Jan 1, 1998

By Yasuo Ojima

The mainstream of copper smelting processes in the world today is a combination of Outokumpu type Flash smelting and PS (Pierse Smith) converting process. Presently it can be estimated that about 50% of the worldwide copper production is produced by the Flash smelting process and 80% by the PS converting process. PS converting process due to its operational flexibility and despite its batch character of operation has been widely used in many smelters for more than 100 years. However, an environmental issue has been pointed out related to this process because of the difficulty of handling the fugitive gases. Recently several copper smelters in the world have been newly construeted and others have executed major modification and modernization. The continuous converting process has been applied in many of them instead of PS converting process. This paper compares PS to the emerging continuous converting process and makes a prospect of the future of the copper converting process.

Jan 1, 2003

By W. G. Davenport

This chapter examines three minor influences on flash smelting&apos;s industrial oxygen and oil requirements, i.e.: (a) recycle of molten converter slag to the flash furnace (b) gangue oxides and carbonates (e,g, Ah03, CaC03) in the flash furnace feed (c) minor sulfides (e.g. NiS} in the flash furnace feed. It then examines the. sensitivity of our flash furnace calculations to previously ignored aspects of smelting chemistry -Cu, S and Fe304 in slag and 0 in matte.

Jan 1, 2001

By E. James Quinn

Solvent extraction technology using EHEHPA (2-ethylhexyl phosphonic acid, 2-ethyhexyl mono ester) is the norm for industrial separations of rare earth elements. This process has some shortcomings, including a large number of stages compared to most SX processes and high acid requirement for stripping of the heavy rare earths. In this work, we examine a number of alternative mixed solvent extraction systems: (i) Mixtures of organophosphonic and phosphinic acids such as EHEHPA/Cyanex 272 or Cyanex 572; (ii) Ionic liquid mixtures of EHEHPA with quaternary ammonium chloride (Aliquat 336); and (iii) Mixtures of carboxylic acids for yttrium/lanthanide separations. We discuss and compare the efficacy of these systems with reference to the Nd/Sm separation, which is of industrial significance. Based on the extraction chemistry and the use of modelling tools to define the counter-current solvent extraction circuit, we present a techno-economic analysis of a separation plant and discuss the impact of various solvent systems on the capital expenditure (CAPEX) and operating costs (OPEX).

By Bryce Clark

An outline of the current world&apos;s known sources and resources of cobalt, looking at both land and possible undersea deposits, is given as a prelude to an examination of current and historical actual world production on geographic/company basis. These production figures will be compared to apparent consumption by segments, both geopraghically and end-use based. Consumption of cobalt has been regarded as price sensitive and a historical look at prices against all other figures will be considered. Included in this scenario will be a brief overview of cobalt&apos;s uses and a comment on future trends. Tables will include: Resources, Production, Consumption, Prices, Markets.

Jan 1, 1993

By O. Durand

The Cerro Verde Hydrometallurgical Plant, located at Arequipa in the southern part of Peru, started its operation in 1977 with a design capacity of 33,000 MT/year of copper cathodes. The plant has treated 61,055,000 MT of ore mainly oxides with a content of 1.01% total copper and 0.67% of soluble copper. The leaching plant has three pads that produce 4.0 gpl copper solution. The solvent extraction plant has four trains with three extraction stages, two stripping stages with a single mixer in all stages. The mixer-settlers are 316 stainless steel and the pumps are vertical turbines. The flowrates of 1,300 gal/mil of aqueous and 1,300 gal/min of organic at a 1/1 ratio. The electrowinning plant contains 208 commercial cells and 18 starting sheet cells. Each cell has 47 anodes and 46 cathodes. In addition to describing the hydrometallurgical plant, this paper also mentions efforts directed at reducing costs and improving operations. The initial results from leaching secondary sulfides, which started October 1985, are also discussed.

Jan 1, 1987

By W. G. Davenport

The flash furnace is used for smelting concentrate to (i) high-Cu matte and (ii) molten metallic copper. It is also used for converting solidified/crushed matte to molten metallic copper. This is flash converting. It consists (Table 20.1, Fig. 20.1) of: (a)tapping molten 65 to 72% Cu matte from a flash smelting furnace (b) granulating the molten matte to ?1/2 mm particles in a 103 m3/hour water torrent (c) crushing the granulated matte to 50 µm in a vertical roller mill (d)drying the crushed matte (e) feeding the dry particulate matte to a second flash furnace for oxidation converting to molten copper. In 2000, flash converting is being used by Kennecott Utah Copper (George, et al; 1995; Newman et al, 1998, 1999a,b). A second installation is being designed for the Chuquicamata smelter (www.outokumpu.com [October 12, 2000]), The potential uses of flash converting are: (a) as the second half of a flash smelting/flash converting coppermaking sequence (b) as a continuous converting alternative to batch submerged tuyere converting. This chapter uses our flash furnace matrix to determine the %O2-in-blast, industrial oxygen and oil requirements for converting solidified 65% and 72% Cu matte to molten copper. It then discusses choice of feed matte grade and other aspects of the process.

Jan 1, 2001

By Qiu Dingfan

The Slurry Electrowinning Process (SEP) is a new hydrometallurgical method and clean technology, Sulfide ores can be treated by the SEP without S02 emission and the sulfur from the sulfides can be recovered in element form which is easy to stockpile and can be transported at low cost. In a special slurry electrowinning cell one can achieve at the same time the leaching of elements from the feed and the electrowinning of metals from the electrolyte, Because the anode reactions are utilized for leaching of some elements the consumption of the energy is decreased, SEP also has the advantage of separation some elements, It is especially suitable for treatment of complex concentrates containing Pb, Cu, Au, Ag and S, which could hardly be accepted by any smelter. In this work, the behavior of different metals in this process has been studied and it was found that the separation of metals in some minerals is possible through the SEP, Beijing General Research Institute of Mining and Metallurgy (BGRIMM) has studied the possibility of the SEP to treat bismuth concentrates containing S, Be and F in laboratory and pilot-test scale as well as in commercial plants, The commercial plant was set up in 1997, It has been in operation since that time, According to the results of laboratory experiments and pilot- plant test, a new plant to treat complex gold minerals was set up in 1998 and is in operation in 1999

Jan 1, 2003

By Y. Pokhvisnev, S. Vandariev, A. Yatshenko-Juk, V. Valavin, V. Romenets

The technology of the liquid-phase reduction process known as Romelt was developed in the Moscow Institute of Steel and Alloys in 1979. The pilot plant was constructed at the Novolipetsky Steel Works (Russia) in 1984. Investigations into processing zinc-containing blast oxygen furnace dust and slag from the Lead and Zinc Works at the pilot Romelt plant proved the perspective of using this technology for processing zinc and lead-containing materials. In this article, the description of Romelt technology, basic technological information of trials at the Romelt plant using zinc-containing materials, compositions of charging materials, metal, slag, gas and dust are presented. The influence of flue gas composition on the composition of zinccontaining dust is shown.

Jan 1, 2000

By Orlando C. Gaspar

The textures of the ores, the fine mineral intergrowths, the complex distribution of the deleterious minor elements, and the low base metal contents in some ore types, pose many technological problems to the beneficiation of the volcanogenic massive sulphides occurring in the Iberian Pyrite Belt. In particular fine intergrowths of the base metal sulphides with pyrite impose extremely fine liberation sizes (Kao=15 to 25um). The mineralogical, textural and metallogenic studies have provided an understanding of the distribution of vertical and lateral metal zoning in the ore bodies. Mapping of the ore types, carried out by mine geologists, and the metal zoning patterns computed from data base have shown that ore types are distributed as ore lenses, and that vertical and lateral base metal zoning exists in several orebodies. Since ore processing efficiency is affected by ore textures, and because the same mineral often shows different textural features, a relationship between the textures of the feed ores and those of the middlings must be established for all ore types defined at the deposit scale. For supplying, on time, the information needed for the optimization of the concentration processes, empirical methods of determining the mineralogical and textural characteristics of the several ore types have been developed.

Jan 1, 1995

By Nina Bianco, Diana Drinkwater

MetSkill is a professional development program for metallurgical engineers that integrates with normal duties in their first one or two years of service. Graduates work together on a structured technical project, facilitated by specialists and supported by formal learning, and ultimately reported to their technical managers. The program enables graduates to “fill the gaps” in their undergraduate education, which is increasingly pertinent as engineering degrees become more general. Participants report that they enjoy the focus on more challenging (rewarding) aspects of their jobs and feel more confident about problem solving. Sponsor companies add that the relationships developed with external technical specialists enhances opportunities for innovation and development. MetSkill was delivered to two major resource companies in Australia in 2012. This paper provides an outline of the program and the reasons for its success, and demonstrates how the learning model could be applied to groups of graduates in other engineering disciplines.

Jan 1, 2014

By Kazuteru Tozawa

Surface tension, density and viscosity coefficient of acidic copper sulfate solutions simulating electrolyte solution for electrolytic production of copper have been measured and are summarized as a function of the solution composition and temperature. Nickel sulfatc is taken to be a representative coexisting sulfate that affects the physical properties of the copper sulfate electrolyte solution. The sulfates in the solutions, including sulfuric acid, increase the physical properties under consideration. Gelatin, representing organic additives for electrolyte solution, was found to sensitively affect the surface tension of the solution at low concentration of up to 200mgIL. The surface tension was markedly lowered by the addition of gelatin and the increasing concentration of gelatin led to a more pronounced decrease in the observed values. The surface tension gradually increases with time after addition of gelatin and the increase is enhanced by higher acid concentration and higher temperature. The observed change in the surface tension is considered to reflect the preferential adsorption of gelatin to the bubble-solution interface and the decomposition of gelatin due to hydrolysis to form various molecules having smaller molecular weights.

Jan 1, 2003

By G. A. Bala

As part of ongoing research to define mechanisms of microbial enhanced oil recovery (MEOR), this work describes the activity of Bacillus l1chen1formis JF-2 (ATCC 39307) Mosurfactant against crude oils with varying compositions. Surfactant based MEOR improves oil recovery by lowering the oil/brine interfactal tension (IFT) therefore permitting oil to be displaced or solub1lized into the aqueous phase.? MEOR is an Enhanced Oil Recovery (EOR) process which allows for the introduction of chemical and miscible fluids, in the form of microbial metabolic end-products, through the injection of microorganisms into the reservoir or stimulation of indigenous reservoir microbial populations. These microorganisms represent a replenishable in situ source of acid, gas, biopolymer, solvent, or surfactant products which can be. supported and manipulated by the addition of simple and inexpensive nutrients to enhance the recovery of oil. Microbially mediated surfactant production represents one mechanism of MEOR. Bacillus licheniformis JF-2. has been used in a mode 1 MEOR system based on Berea sandstone cores (permeabilly .85 to 400 md) to examine surfactant based MEOR of medium to heavy crude oils (API gravity 38.1° to 17.5°). Enhanced oil recovery was achieved with all oils tested using either cell free culture supernatants or microbial suspensions as injectants with no detrimental effect to the oil. Spatial distribution of cells following mf?crobtal flooding was analyzed with scanning electron microscopy. Data indkate complete distribution of cells with a predominance of organisms located distal to the point of injection. There appears to be no sign:if1cant recovery trend with respect to oil composition.. The biosurfactant produced by Bacillus lichen1form1s JF-2 lowers the interfacial tension of all oils tested equally well.

Jan 1, 1991

By Markus A. Reuter, Robert Matusewicz

"Consumer products are a complex man-made mixture of sometimes in excess of 50 elements. In order to recover these complex mixtures of elements either as metals, compounds or energy requires versatile technology in physical separation but also smelting and energy recovery. This paper explores this by referring to the innovative application of Top Submerged Lance (TSL) technology and associated theoretical and environmental aspects to process (recycle) post consumer materials and industrial intermediate products and residues. A diversity of applications has been tested in Ausmelt’s pilot plant in Dandenong and many have gone to commercial scale globally. This paper reviews the varied applications ranging from e-waste recycling, lead and NiCd battery recycling, metals recovery from slags, zinc leach residue processing, electric arc furnace (EAF) dust, Municipal Waste Incinerator bottom ash processing, carbon containing residues such as retort ashes and spent pot liner from the aluminium production process as well as use of the technology for materials such as automotive shredder residue (ASR) and plastics. Introduction The modern resource cycle is a link between primary production of metals linked to the recycling of post-consumer goods. The sometimes complex combinations of materials and metals in consumer products such as televisions depicted by Figure 1, does require a range of technology to recover materials, metals and energy for reuse and/or recycling in an economically feasible as well as environmentally friendly manner."

Jan 1, 2008