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By M. Giralico

Optimized mixer settler designs will now handle flows of over 25,000 GPM. The size and expense of the equipment hamper experimental settler optimization efforts. Computational Fluid Dynamics (CFD) is a timely and predictable tool for settler design development. In the past, CFD has been used to evaluate only the flow field in pumped and auxiliary tanks. A similar numerical analysis is used to evaluate settler flow and phase separation. Phase separation is analyzed using multiple species for the aqueous and organic phase. Experimental validation shows good agreement between the computational and experimental solutions in both flow field and phase separation. The computational model is used to show performance differences between various choices of settler geometry, liquid depth, with variable flow rates. Understanding the differences allows the development of optimized settler designs. System improvements are predicted to lower entrainment levels further and/or allow new smaller footprint designs. This paper focuses on the major design components of the settler and how future technological advances will lead to further improvements in their design. LIGHTNIN?s new designs will handle tomorrow?s production requirements, while maximizing profits.

Jan 1, 2003

By D. M. Hausen

It has been demonstrated that microscopic techniques can be applied in a practical manner to the study of spodumene liberation in the processing of pegmatitic ores at the Kings Mountain spodumene plant, Kings Mountain, North Carolina. Spodumene and associated non-opaque gangue minerals are identified and quantified by microscopic point-counting of polished thin sections of heads, concentrates, middlings and tails fractions. Specially prepared polished thin sections? provide uniform thickness of particles for measurement of diagnostic optical properties and the alternate use of incident and transmitted light in distinguishing the various gangue and ore minerals. Spodumene is commonly associated and interlocked with quartz, albite, microcline and muscovite. Concentrate grade depends on the degree of spodumene liberation, which in turn depends on the crystal size and textural association of interlocked minerals. The liberation of spodumene can be measured as a function of screen size by means of microscopic point-count data. Microscopic data also provide useful metallurgical information about the nature of diluent minerals in spodumene concentrates, and the form of lithia losses in the tails. Lithium assays correlate closely with microscopic spodumene analyses in various flotation products from Foote Mineral's Kings Mountain plant, and confirm the applicability of quantitative optical microscopy to the study of liberation and recovery of spodumene from pegmatitic ores. A better understanding of recovery-grade relationships was developed as a result of quantitative microscopy studies.

Jan 1, 1981

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

By N. D. Schupp

The Doe Run Company's Herculaneum, Missouri lead smelter has existed in continuous operation since 1892. Throughout the history of the plant extensive developments have been made to improve throughput, increase productivity, decrease operational costs and improve technology, while remaining an environmentally responsible producer of high quality primary lead in the international market. This paper provides an overview of the Herculaneum smelter, focusing on the most recent configuration of the operations. The paper includes discussion on all the aspects of primary lead production at the Herculaneum smelter.

Jan 1, 2000

By J. Wendt, P. R. Sahm, T. Uloth, M. Weck, F. Foertsch

"The FEM program systems CASTS (Computer Aided Solidification TechnologieS) (1) and FINELF (FINite ELement Frontal Solver) are used to optimize a thin walled die casting. After a short description of the programs it will be worked out how to use them not only for simulating solidification processes but also for optimizing the design of workpieces. The calculations will be done for an automobile's support bracket which is manufactured in a well known car factory in Stuttgart, FRG.IntroductionAt the Aachen Foundry Institute the software package CASTS was developped to simulate solidification of castings. In order to optimize the whole manufacturing process it does not appear sufficient any more to take into account only the specific aspects of casting. For instance one has to consider additionally the stress situation under service load. For this reason the Foundry Institute together with the Aachen WZL-Institute (Machine Tool Laboratory) and the car factory mentioned above started to probe into a first step in that direction. Figure 1 shows the support bracket which shall be optimized."

Jan 1, 1986

By Ana P. Paiva, Marc F. Comella, Sandra S. Reis, Joao N. Reis, M. Soledade Santos

"In this work, the influence of the malonamide structure, acidity of the aqueous phase and diluent on the equilibrium interfacial tension (IT) of N,N'-dimethyl-N,N'-diphenylmalonamide (DMDPHMA) and N,N'-dimethyl-N,N'-dicyclohexylmalonamide (DMDCHMA) in 1,2- dichloroethane (1,2-DCE), and DMDCHMA in toluene, with aqueous HCl, were investigated. IT isotherms were determined using the Du N ouy ring method. Densities of the organic phases were determined, and used to screen solute-diluent interactions. Formation of third phases was never observed; furthermore, ITs increase with the phase separation period, constant values being obtained for separation periods larger than 1000 seconds. Each malonamide interfacial efficiency at the oil/water interface is interpreted in terms of malonamide basicity, diluent polarity and malonamide - hydrochloric acid- diluent interfacial interactions.IntroductionFor several years now, N,N'-tetrasubstituted malonamide derivatives have been extensively investigated as liquid-liquid extraction agents since they were first proposed as the organic components of the DIAMEX process, with the aim of advantageously replacing tributylphosphate in PUREX [1]. Therefore, a significant part of research studies with malonamides appearing in the literature deal with the extraction of major and minor actinides in real or simulated spent nuclear fuels in nitric acid solutions [2]. Under typical experimental process conditions, the tendency shown by some N,N'-tetrasubstituted malonamide derivatives to aggregate in the organic phase, leading in a few cases to the formation of undesirable third phases, has been remarked and consequently thoroughly investigated [3, 4]. The increasing use of chloride streams as hydrometallurgical aqueous feeds is becoming a reality, and this fact is obviously deeply founded on an extensive research carried out to recover value-adding metals from these media. Following this trend, a number of N,N'-tetrasubstituted malonamides have already been screened for the recovery of iron(III) [5, 6] and platinum-group metals [7] from hydrochloric acid solutions. The results obtained are quite promising either in terms of total metal ion recoveries or selectivity patterns achieved. The formation of a third phase when iron(III) was extracted by the tested N,N'-tetrasubstituted malonamide derivatives has never been observed under the adopted experimental conditions, and the extraction data collected would need to be reinterpreted accordingly if any aggregation phenomena involving the considered extraction systems were to take place."

Jan 1, 2011

By S. W. Marcuson

Smelting of nickel-copper sulfide ores at Vale Inco’s Sudbury operations commenced in 1888 and the first converting plant went into operation in 1892. As the demand for nickel grew, the smelting operations expanded and by the 1960’s the Copper Cliff Smelter featured the longest converter aisle in the world with space for nineteen Peirce-Smith converters. During this long period, different converting techniques and vessels were employed. The evolution of converting is reviewed with special emphasis on the modifications made to the Peirce-Smith vessel to accommodate the metallurgical and process needs of the changing times.

Jan 1, 2009

By M. Fafard, R. Ahmed, O. Dion-Martin

"The optimization of aluminum sheet and tube forming needs the use of large strain finite elements software. The precision of the predicted results from those simulations depends mainly on the quality of constitutive law of the material used. In order to improve quality of these simulations, Barlat has suggested a new yield function named YLD2000-2d. This criterion describes the anisotropic behavior of the rolled aluminum plates. This work consists of characterizing the AA5754 alloy and estimating the material parameters needed for the YLD2000-2d criterion in LS-DYNA. In order to get these parameters, various mechanical testing were performed such as bulge and tensile tests. Moreover, the bulge test was also used to obtain an estimation of work hardening curve in large strain condition, up to 50%. The objective of this paper is to share the experimental results of the characterization of AA5754 aluminum alloy.IntroductionResearchers from National Research Council Canada's Aluminium Technology Center (NRCATC) and Aluminium Research Centre - REGAL, are working on aluminium tube hydroforming processes of AA-5754-0 alloy, used in automotive industries. Hydroforming process presents several difficulties such as wall thinning and section changes. In order to control them, some parameters can be set during the process like pressure rate and end feed level [1]. Given the complexity of the parts and the variability of the control parameters, the use of finite element method (FEA), like LS-DYNA, based on large strain theory is thus necessary. The accuracy of predicted results depends mainly on the quality of the constitutive law used to model the behavior of material. FEA results seem to be valid with the von Mises yield criterion used in some cases. But, given the anisotropic properties of the AA-5754 alloy, a more appropriate criterion could be used. The *MAT_ BARLAT YLD2000 shell material criterion, developed by Barlat [2], who's taking into account the anisotropic behaviour, was chosen due to its large flexibility and its good adaptation to particular elastoplastic behavior of aluminum. However, the use of this criterion needs to determine some material parameters by experimental way."

Jan 1, 2013

By Marcelo Mourao, Adolfo Pillihuaman, Alberto Nogueira, Cyro Takano

"The self-reduction is an alternative and promising process for production of pig iron because offers decisive benefits such as enhancing the reaction kinetic with decrease in fuel consumption and C02 emissions. The self-reduction mixture of iron ore fines, carbonaceous reducer and additives for slag forming components, without agglomeration, was tested in a laboratory rotary kiln. The additives for slag were defined for presenting two different estimated liquidus temperatures (1623 Kand 1773 K) to verify the effect of these temperatures on the iron-carbon nuggets coalescence process. These mixtures were tested at 1673 and 1773 Kin an experimental rotary kiln. After reduction-melting and coalescence processes the samples were disaggregated and the iron nuggets were classified by size. It was considered that nuggets larger than 7,93mm would be a good reference for coalescence index. Low liquidus temperature slag presented 37% of this larger fraction against only 13.5% for high liquidus temperature one. The low liquidus temperature slag would facilitate contact between the particles of iron-carbon in a rotary kiln, enhancing the coalescence.IntroductionThe slag composition usually depends on the reducer ash composition, the ore gangue, the binder composition and any fluxing material [l], and the mechanism of carbon transportation in slag that contains iron oxide reducible by carbon can be explained by the oxide reduction and the metal carburization. During carbon transportation, the carburized particle is transported to slag-metal interphases by the gravity effect, being assimilated by the metallic phase [2]. When the slag's iron oxide comes in contact with the solid carbon, it is immediately reduced, forming Fe particles and CO bubbles as it is shown in the figure l(a). The Fe particles are carburized by carbon particles; they are liquefied simultaneously in the carbon-slag interphase. The Fe-C liquid particles are transported from the slag-carbon interphase to iron-slag interphase as a result of slag flow, based on the surface tension difference (Marangoni effect), figure l(b). The Fe-C liquid particles coalesce on the iron surface and the carbon is immediately diffused in the iron as it is shown in figure l(c). The reduced iron is carburized continuously by repeated sequences [3]."

Jan 1, 2013

"Mechanical alloying (MA) synthesizing technology and thennohydrogen processing (THP) were utilized to produce nanocrystalline Ti-MMC's reinforced by TiB intermetallic compound by using TiH2-B powder mixtures. Powders MA'ed up to 8 hours were examined by X-ray diffraction and SEM study. All MA'ed powders afterwards were HIP'ed at 700, 800 and 950EC for 1 hour. Detailed XRD, SEM and TEM study of the samples were carried out to determine the structure and micrography of the Ti-TiB MMC material processed by MA+THP approach followed by HIP'ing at high temperatures.IntroductionThe fiber reinforced titanium base composites [1,2] which possess a great resistance to high temperature have been investigated. In these studies fibers of C and SiC were used as reinforcing materials. However, these fibers react with Ti-matrix at elevated temperature resulting in product formation at the interface between the matrix and the fiber. Because of the chemical reactions, strength of the product MMC material diminishes.In conventional techniques of whisker reinforced composite material production, the mixtures of matrix metal powders and dispersed fibers are consolidated by hot pressing, HIP and/or hot extrusion. These techniques, however, have some shortcomings. Hard and brittle fibers could be broken during mixing cycle of the processing. Consolidation techniques could also be the cause for fiber breakdown. Attaining of the uniform dispersion of fibers into the metal matrix is not an easy process. The chemical reactions at elevated temperature exposures in the interface between the matrix material and fiber reinforcement cause product formations leading to poor mechanical properties."

Jan 1, 1998

By B. Bichel

For the last 70 years, molten blister copper has been transferred by rail in hot metal cars from the Copper Cliff Smelter to the Copper Cliff Copper Refinery (ex Ontario Refining Company) where it was processed in two (2) reverberatory anode furnaces by poling with logs, cast on four (4) wheels, and then electrorefined. This practice was modernized in 2001 with the installation of two (2) rotary anode furnaces at the. Copper Cliff Smelter which employ steam and. natural gas for reducing and which provide a significant reduction in emissions. A new casting shop with a single anode casting wheel is used to cast regular and stripper constant weight anodes which are transported by truck to the Copper Cliff Copper Refinery for anode preparation and electrorefining. This paper provides an overview of the copper circuit at the Copper Cliff Smelter and a description of the CDN$31 million capital project.

Jan 1, 2002

By Michael G. Mayer

Since its invention in 1859 various designs of lead batteries have evolved to meet commercial needs for traction applications and standby power. In recent years major developments have taken place in lead alloys and the chemistry and mechanical design of industrial lead batteries. These are reviewed in relation to their commercial application together with the new type of maintenance free gas re-combination lead-acid batteries which are opening so many new markets for lead.

Jan 1, 1990

By S. J. Thiele, T. Newton, W. Magalhäes, T. Takayama, J. Welsh

Companhia Paraibuna de Metais (CPM) is presently pursuing a zinc production expansion project. Besides increasing production, the goal of the project is to address existing problems while providing a platform for a proposed twofold increase in production in 2003/2004. Therefore, the current expansion strategy was formulated to address present and future requirements. Computer simulation modeling and full scale plant testing are being used to generate data to optimize the operating conditions and to perform a sensitivity analysis. The initial phase of the project, which will boost CPM's capacity to 86,000 t/y of marketable zinc, is to be completed in September 2000.

Jan 1, 2000

By R. N. O'Brien, E. Peters

"It has been discovered that copper concentrates can be leached in strong (40-60%) sulfuric acid with nitric acid, or with oxygen if nitric acid is present as a catalyst. Chalcopyrite is rapidly decomposed at temperatures well below the boiling temperature of the lixiviant (-150 C.) and the resulting copper and ferric salts are precipitated as CuS04.H20 and FeH(S04)z.4H20. Other metal sulfides such as zinc, lead, nickel, etc. are also converted to sulfates that are nearly insoluble. Sulfur is partially converted to elemental and partially to sulfuric acid. Reduction products of nitric acid can be recovered from the distillate with good recovery. Conversion of as-received copper concentrates is largely complete in about 1 hour. Introduction9 molar sulfuric acid is an unusual hydrometallurgical lixiviant: it has a boiling point of about 150 C. and a low solubility for base metal sulfates. Below about 6 molar acid, the boiling point falls below 120 C. and yields much higher sulfate salt solubility, while above 12 or 13 molar acid and at higher temperature sulfuric acid becomes an oxidizing agent, yielding gaseous S02' Thus, sulfuric acid within this range of concentration is capable of acting well above the temperature of boiling water without requiring autoclave conditions, and if typical oxidative leaching conditions are applied to suspended mineral sulfide concentrates, it is possible to obtain a conversion of these sulfides into 'crystalline sulfates. Thereafter, the sulfates can be separated by filtration or by solid - bowl centrifuge and the solution can be recirculated to the reactor vessel. Meanwhile, the solid sulfates can be treated in a typical hydrometallurgical circuit, i.e., dissolved in a return stream that is essentially water, separated from each other by, for example, solvent extraction, and recovered as metals by electrowinning."

Jan 1, 1997

By D. J. Webb, D. G. Reynolds, D. W. Ashman, D. W. Goosen

Cominco Limited operates an integrated zinc-lead complex at Trail, British Columbia, Canada. Central to the successful operation of this complex is the treatment of zinc leach residues through the lead smelter. In 1997, Cominco started up a new lead smelter using KTVCET flash smelting, a state-of-the-art conventional slag fuming furnace, and a new drossing plant. The smelter has fully met the requirements for environmental performance, reduced energy consumption, and lowered labour costs. This paper provides a description of the new smelter and discusses the problems encountered during the start-up, as well as the solutions to those problems. Recent operating results are presented. Lead-Zinc

Jan 1, 2000

By Z. R. Llanos, W. G. Deering

Gulf Chemical and Metallurgical Corporation (GCMC) has been operating facility for treatment of spent catalysts in Freeport, Texas since 1974. Recently, GCMC expanded its operations with the addition of an electric furnace for the production of fused alumina and mixed alloys. GCMC and its affiliate Sadaci, started up a new pre-treatment facility in Ghent, Belgium in 1998. GCMC is also part owner of Bear Metallurgical Corporation, a major producer of ferroalloys in the United States. This paper reviews the processes at these facilities. Changes in the management of hydrotreating and hydrorefining spent catalysts are discussed in light of recently issued federal regulations that made the majority of spent catalysts a listed hazardous waste.

Jan 1, 2000

By J. Winters, L. Vos, C. Canoo

Committed to a sustainable development of zinc applications, Union Miniere is investigating processes for the minimisation of waste and residues originating from the classic hydrometallurgical zinc process. In that context, Union Miniere has developed a method for the cold inertisation and solidification of goethite, the Graveliet® process. The result is a hard and inert gravel that can be used in the building industry. During the past two years, a pilot plant for the production of Graveliet® has been built and operated. In the present paper, the Graveliet® process and the pilot plant are described after which the properties of the produced gravel are discussed, from both a mechanical and an environmental point-of-view. Graveliet fulfils the criteria for use as a secondary building material. The GravelietJ process is a viable technology to avoid stockpiling of goethite residues and it thus assures the long-term development of the hydrometallurgical zinc process.

Jan 1, 2000

By G. Sterzik, W. A. Jankola, T. L. Salway, D. J. McKay

At Trail, British Columbia, Cominco's zinc leaching and solution purification processes include direct pressure leaching of zinc concentrates, leaching of fume from the lead smelter, leaching of calcine and electrolyte purification. These processes have been adapted to match the unique characteristics of Cominco's integrated zinc and lead operations. Recent modifications include changes to the purification process and iron-residue handling circuits. In 1997, a new five-compartment autoclave, complete with ancillary equipment, was installed in the pressure leaching plant. This paper discusses these changes, the current flowsheet and further improvements.

Jan 1, 2000

By N. Verbaan, E. Bourricaudy, M. Dry

"Starfield Resources is developing a novel circuit for the recovery of nickel, copper, cobalt, iron oxide, sulphuric acid and precious metals from the Ferguson Lake deposit in Nunavut, Canada. In this deposit, pentlandite is too finely disseminated in pyrrhotite for the production of a smelter-grade nickel concentrate at an acceptable nickel recovery, so established technology is not applicable and a novel chloride-based circuit is under development. The enabling aspect of this circuit is the hydrolysis of ferric chloride to hematite, releasing gaseous hydrochloric acid that is recycled. Conventional steps are used for separating and recovering the valuable metals from the chloride solution generated. This paper briefly outlines the circuit and presents the results of experimental work on the enabling steps, viz. the oxidation and hydrolysis of iron chloride to hematite and gaseous hydrochloric acid.IntroductionThe Ferguson Lake bulk sulphide ore body in Nunavut, Canada, owned by Starfield Resources Inc., contains significant amounts of base and precious metals but its mineralogy is such that it is not amenable to conventional processing. Pentlandite, for example, is too finely disseminated in pyrhhotite for even modem techniques such as fine grinding and improved flotation reagents to be effective [ 1] and extracting the value requires processing the entire bulk sulphide, including the pyrrhotite. To give the project a total green footprint, in terms of both carbon emissions and acid rock drainage, Starfield imposed the following requirements:• No reactive tailings to generate acid rock drainage.• No gaseous emissions other than normal atmospheric constituents.• No liquid effluents.• No regular consumption of fossil fuel.• High recoveries of all the valuable metals."

Jan 1, 2011

By Moenster J. A., M. J. Sankovitch

Doe Run's Buick Smelter was converted from a primary lead smelter to a secondary lead smelter in 1991. The recycling facility was designed to produce 60,000 tons of refined lead per year from 110,000 tons of spent starting-lighting-ignition (SLI) batteries and 10,000 tons of lead contained in drosses and scrap. Since commissioning, Buick's refined lead output has steadily increased to exceed 120,000 tons for 1999. The production gains have been the result of continuous process improvements, empowerment of the workforee, and development of additional scrap lead streams. The production gains were accomplished while setting industry standards for employee safety, reducing plant environmental emissions and employee blood leads, achieving ISO 9002 certification, and expanding product lines to meet customer requirements. This paper highlights Buick's major accomplishments through the 1990's.

Jan 1, 2000