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By Milton Manrique, Edgar E. Vidal, Patrick R. Taylor

"Ultrafine zirconium carbide powder has been synthesized using zircon concentrate and methane in a thermal plasma reactor. The effect of several experimental variables, such as power used and zircon particle size, on the conversion has been studied. A thermodynamic analysis of the possible reactions and stable compounds was performed. A mathematical model that describes the in-flight decomposition of zircon particles was developed based on a description of the temperature and velocity profiles calculated in the reactor. It was shown that the formation of zirconium carbide from zircon and methane is thermodynamically possible. Complete 'vaporization of zircon in the reactor is predicted when the particle size is below 45flm and the effective power entering the reactor is 15 kW. The powders were collected and characterized by XRD, SEM, TEM and chemical analysis using ICP. Results of the product analysis indicated the presence of zirconium carbide, zirconium oxide, silicon carbide and silicon oxide.IntroductionIn recent years there has been an increased interest in the production of nanometric sized powders of ceramic materials for use in advanced materials applications. One possible method to produce these powders is with a thermal plasma reactor, which offers high temperatures and fast quenching rates. This technology has been called - Thermal Plasma Synthesis - [1].Zirconium Carbide (ZrCx) has typical properties of transition metal carbides: elevated hardness - between alumina and diamond - a high melting temperature of 3420°C and high chemical stability at room temperature [2]. ZrCx has a Bl crystal structure with deficiencies in the number of carbon atoms in the cell with x between 0.6 and 1 [3]. Different methods have been used to produce ZrC, one method is by direct reaction of zirconium hydride or halide with carbon. Other methods used are direct reduction and carburization of zirconium oxide (Zr02) and reaction of metallic zirconium with a caburizing gas such as acetylene [3]. Recently small films of ZrC have been obtained using a sputtering device [4,5]. ZrC has been used in nuclear plants as a low neutron absorbing and high mechanical resistant refractory material and also as a constituent in cathodes made of UC-ZrC [6]. It is also used in the form of tubes, boats and crucibles to handle molten metals and as part of electronic devices used for thermoionic transducers. Recently ZrC has been used along with zirconium diboride (ZrB2) to produce composite materials [7,8]."

Jan 1, 1996

By D. J. Cassidy

This document discusses commercial strategies and applications of specialty processing plants for the recycling of nickel, copper, zinc and cobalt bearing by-products. For this discussion, I will focus on materials originating from the metal plating, electronic circuit board· and chemical industries. The review of select processes and the required service, sourcing, material handling, processing and marketing strategies necessary for a successful recycling program are highlighted. Materials discussed in this summary include filtercakes, filters, dusts, spent catalysts, spent solutions and solids. Both pyrometallurgical and hyrometallurgical applications to these materials are addressed. A comparison of targeted finished markets, including smelter feeds and value added products are also reviewed.

Jan 1, 2000

By T. J. White

Xtaltite is the trade name for a generic technology which exploits the well known insolubility of some minerals, which naturally incorporate toxic waste elements, to consolidate and immobilise a range of inorganic waste products. It is a specific case of synthetic mineral immobilisation technology (SMITE) which is already used to immobilise high level nuclear wastes (HLW. Although HLW is highly toxic, it exists in relatively small volumes, occurs in central facilities and may be stabilised at low waste loading (< 10 wt%). In contrast, heavy metal wastes are of considerable volume, therefore Xtalitite waste forms must routinely accommodate high waste loadings (usually in excess of 30 wt% for a particular toxic oxide or combination of oxides) and be suitable for fabrication in remote locations using relatively simple technology. This paper details the methodology underlying Xtaltite, with particular emphasis given to the interplay between solid state chemistry, durability and economic considerations. Specific reference is made to the treatment of arsenious and mercurial wastes.

Jan 1, 1994

By Hal dun Kurama

In thus-study, Bigadic upper zone zeolitic tuff, which contains about 87% clinoptilolite was used as an ion exchanger for removal of Pb++, Cu++, Cd++ and Hg++ ions from wastewater. Bench scale experiments with two different glass columns, were carried out continuously under the closed/ open circuit conditions. Before ion exchange tests, zeolite samples were treated with NaCI (6ml/ min. and 42BV). The effects of particle size, bed volume, pH and flow rate on the ion exchange capacity were determined. Under the best operation conditions, the effect of initial influent solution concentration on ion exchange selectivity was tested. As a-result, it was found that the Bigadiç clinoptilolite had the following ion exchange capacities;

Jan 1, 1995

By James C. Foley, David K. Rehbein

"In-situ characterizations of green state part density and sintering state have long been desired in the powder metal community. Recent ·advances in non-contact electromagnetic acoustic transducer (EMAT) technology have enabled in-situ evaluations of the acoustic attenuation and velocity as sintering proceeds. Pure aluminum (99.999%) and aluminum alloy powders were prepared with high-pressure gas atomization (HPGA). The powders were pressed in a uniaxial die and examined with acoustic waves for changes in velocity and attenuation during sintering. The changes in acoustic properties were correlated with sample microstructures and mechanical properties. Evolution of the acoustic echo train during sintering is shown to provide information on the state of sintering as well as having the potential for detection of interior flaws.IntroductionThe versatility of powder metalallurgy (PIM) technology in the manufacture of complex shapes has enabled an increasing amount of wrought and casting production capacity to be converted to PIM technology. However, ultrasonic inspection of green components produced using PIM techniques remains a challenge and is not generally practiced [1]. Inspection of PIM components in the green state is highly desirable, because the green part can be reclaimed with only accepted components being subjected to further costly processing. Another potential benefit is characterization and greater understanding of the sintering process itself. An increased scientific understanding of the sintering process enables intelligent process control, greater reliability of the production process and a lower rate of rejection of the finished product. In order to realize these potential benefits, it is necessary therefore that accept/reject criterion be based on real time nondestructive evaluation of the green-state components and the sintering process.Most current nondestructive inspection techniques suffer from their inability to perform inspections below the near-surface region with the exception of X-ray and to some extent pulsed eddy current [2]. X-ray inspection requires extensive shielding of production personnel and expensive film and film processing. While development of pulsed eddy current techniques have lessened the impact of the well-known skin effect, the depth of penetration of the induced eddy currents remains somewhat of an issue [2]."

Jan 1, 2000

By Kouji Mimura, Tamas Kekesi, Yongfu Zhu, Masahito Uchikoshi, Minoru Isshiki

"The formation and anion exchange sorption of chloro complex ions can offer a great potential to be utilized for the separation and purification of metals in aqueous solutions. Available stability data were primarily used to estimate the predominance of chloro complex species, indicating the feasibility of such separations. Anion-exchange sorption functions, describing the equilibrium distribution of a number of important elements have been determined by the batch equilibrating method in the practical HC1 concentration range. Various oxidation states were stabilized by the addition of appropriate agents. Tendencies in oxidation, complex formation and anion exchange sorption were confirmed by spectrophotometric investigations. Based on the fundamental results, anion exchange processes have been developed for the purification of iron, cobalt, copper and zinc. The efficiency of separation was assessed and the procedure optimized by the analysis of experimental elution curves. Results have demonstrated that by properly controlling the oxidation states and HC1 concentrations, practically all the impurities can be eliminated. Computer programs have been developed to estimate complex formation and redox equilibria, to screen and correct analytical data, to determine distribution coefficients and to evaluate efficiencies of separation.IntroductionBase transition metals have long been used as the staple materials in various fields of industry. In general, there has been an increasing tendency in purity requirements but recent advances have created a rapidly increasing demand for ultra-high purity metals. To give a few examples, ultra high purity copper can be used as bonding wire and interconnection in integrated circuits, or as material for superconductor stabilizing, high-field magnets, beside its use in cryogenics and ultra high vacuum technology [1]. Iron holds promises as a constituent element in the ß-FeSi2 material to be applied in new opto-electronic devices [2] and it is currently used, together with chromium and manganese, in the production of special magneto-optical materials for digital recording. The use of ultra high purity manganese and chromium in semiconductor technology is evolving. Although not considered a transition metal, zinc is also treated here because of the major significance in compound ZnSe semiconductors [3], and the possibility to purify it by the anion exchange method."

Jan 1, 2000

By Robert R. Beebe

On the night of August 1&apos;9-20, 1995, seepage was seen at the toe of the Omai tailings dam in Guyana. The mill was immediately shut down, and within two hours the flow, then mostly water, was diverted into an inactive mining pit nearby. At about the same time a second more serious break occurred at a point where water and solids could flow directly into the Omai River. By the time Ii coffer dam could be completed in the early morning of August 24, some 4.2 million cubic meters of tailings water and solids had escaped from the dam, of which nearly2.9 million cubic meters had reached the Omai River. This paper outlines some initial Process considerations and operational decisions which might have contributed to the dam&apos;s failure, describes how the Government of Guyana and the operator, Omai Gold Mines Limited, cooperated in dealing with immediate problems and shows how the Government set about investigating the accident. In particular, the paper details the work of a Process Review Committee comprising Guyanese and foreign experts convened to assess the gold processing and effluent management systems at Omai, and to recommend actions where appropriate.

Jan 1, 1998

By P. Aguirre

Recovery of zinc, copper and nickel from electroplating waste solutions was achieved &apos;by using a Pulsated Percolated Porous Electrode "3PE" reactor on a pilot plant scale. Intensity - potential curves were used to study the possibility of metal removal and to define the working potential range. The present study describes the use of the 3PE reactors in several electroplating industrial units for the decontamination of their effluents. These effluents were issued from different industrial solutions such as cyanide, sulfate, chloride and Watts baths. Using the stripping curves, deposition rates and electrical efficiencies were determined as function of the metal concentrations in these effluents. Their decontamination could be achieved to the level of few ppm of metals with reasonable current efficiencies. The recovery rates of zinc and copper were about 93 and 99 %, respectively. The. treated effluents contained less than 7 and 1 % of the initial contents of Zn and Cu, respec¬tively. This process allows the recycling of the recovered metals and leads to water saving.

Feb 13, 2014

By Carlos G. Levi

"The principles involved in the rapid solidification of supercooled metal droplets and existing numerical models are reviewed. The limitations of these models for studying alloy solidification are discussed in terms of the effects of alloying elements on the relevant heat transfer, thermodynamic and kinetic parameters. Analysis of the enthalpy-temperature diagram reveals how the extent of rapid solidification is hindered by the addition of solute. A solidification model incorporating thermodynamic and kinetic relationships into a Newtonian heat transfer formulation is used to analyze the thermal history and concurrent solute redistribution during recalescence. IntroductionIt is well acknowledged that microstructural evolution during solidification is intimately associated with the thermal history of the liquid-solid interface. Structural parameters like chemical homogeneity, morphology and size scale of the phases can be related to the interfacial temperature and velocity. These in turn change by the interaction of the interface with the thermal and solutal fields in its neighboring environment.The thermal history of powder solidification can be conveniently described on the enthalpy-temperature diagram for a pure metal shown in Figure 1 and discussed in detail elsewhere [1). A system can conceivably follow any path of decreasing enthalpy in the supercooled region of Figure 1 (~ < 1), starting at the nucleation temperature (oN < 0) on the liquid line, and ending at some point on the solid line. A vertical path represents an isothermal transformation, of which a limiting case is solidification without significant barriers to nucleation and growth, with the interface at the equilibrium temperature TM (path one in Figure 1). A horizontal path represents isenthalpic (or adiabatic) solidification whereby the system could form an amount of solid proportional to the initial supercooling of the liquid without further heat loss to the environment. A liquid that can completely transform to solid under adiabatic conditions is said to be ""hypercooled""."

Jan 1, 1986

By Teruo Bitoh, Shogo Izumi

"The effect of B203 flux melting on the structure and the soft magnetic properties of the (Feo.1sBo.20Sio.os)96Nb4 bulk metallic glasses prepared by casting has been investigated. The ringshaped bulk specimens were prepared by the B203 flux melting and copper mold casting. It was confirmed that the flux melting promotes the precipitation of the a-Fe(-Si) and Fe2B phases in the central region of the specimens. The ring-shaped bulk specimens show a flat hysteresis curve, indicating a good linear relationship between the magnetic induction and the applied magnetic field. These results show that it is possible to develop a new soft magnetic material that exhibits constant permeability, which is necessary for producing inductors and choke coils.IntroductionSince the success of forming Fe-based bulk metallic glasses (BMGs) with good soft magnetic properties, great attention has been developed to synthesis and properties of the BMGs [l, 2]. The BMGs have high glass-forming ability (GFA) and, therefore, they can be used to prepare bulk amorphous alloys with a thickness of the order of a few millimeters by casting. The soft magnetic properties of Fe-based BMGs are better than those of ordinary amorphous alloys; therefore, these BMGs have wider applications as soft magnetic materials [3-5]. It is often required for soft magnetic materials that the shape of the hysteresis curve is changed according to the demands of applications. For example, materials with ""flat hysteresis curves,"" which means the magnetic flux density (B) and the applied magnetic field (H) show a linear relationship up to rather high magnetic field, are necessary for producing inductors and choke coils. Flat hysteresis curves can be easily achieved by creating an air gap in the magnetic path. However, magnetic flux leakage generated in the air gap inhibits high-density packing of the electronic components. In order to achieve flat hysteresis curves without creating an air gap, Fe-based ordinary amorphous alloys are subjected to crystallization by annealing and transformed into thin surface layers of a-Fe; the crystallization results in the compression of the remained amorphous phase [6]. Another way to achieve flat hysteresis curves is the formation of secondary phase (such as Fe2B) that act as pinning site of magnetic domain wall displacements [7]."

Jan 1, 2013

By Akira Nishikawa

During the twentieth century the copper smelting industry achieved dramatic expansion corresponding to the vast growth of global economy. This was largely due to innovations in pyro-metallurgical processes, such as autogenous smelting and continuous smelting and converting technologies. However, as copper production capacity increased, its impact on the environment also could not be ignored, and thus with increasing global environmental awareness, many smelting operations either had to renew or rebuild their facilities. In addition to these changes, in places like Japan and Europe, with scarce primary resources, the treatment and recovery of metals from a variety of items such as car shredder dust, used electrical appliances and electronic devices, on top of scraps traditionally treated, is having a profound effect on the reduction of waste and the preservation of primary resources. Thus compared to the days when copper smelting focused on the environmental control in order to break with "Smoke Stack Industry", copper smelting today is making an important contribution to the sustainable development of human society.

Jan 1, 2003

By V. Ramachandran

Over the past 20 years, water treatment plants have been built at various Asarco facilities to effectively handle the process waste streams that need to be bled from the system. The current paper review the several operations with reference to (a) waste streams processed, (b) process chemistry, (c) discharge options and recovery of treated water, and (d) sludge disposal.

Jan 1, 1994

By Hongmin Zhu, Kai Huang, Shuqiang Jiao

"Garlic peel was used as the raw material to synthesize the biosorbent for the selective recovery of precious metals from the acid chloride solution. Garlic peel is rich in carboxyl-, amino- and thiol-groups, has the potential of exhibiting high affinity to Au(III) when appropriate chemical modification process was employed. Here in the present study, the biosorbent was prepared by cross-linking garlic peel particles with concentrated sulfuric acid. Adsorption tests for mixing different metal ions such as Au(III), Fe(III), Cu(II), Ni(II) and Zn(II) from various concentrations of hydrochloric acid media indicated that Au(III) was selectively adsorbed on the cross-linked garlic peel gel over the other coexisting base metal ions investigated. The crosslinking mechanism and selective adsorption of Au(III) were also investigated briefly.IntroductionPrecious metals are quite popularly applied in the modern industries such as jewelry, electronics and electrical devices, catalysts in chemical industry, etc. While their high values, limited deposit and quite large demand in industry makes its recovery from the industrial wastes, typically e-wastes, quite necessary. Actually, many techniques have been developed to recycle and recover the precious metals from various industrial wastes effectively in last decades, but the cleaning and ecofriendly processes are still seriously scarce [1]. Taking into account of the typical recovery processes using cyanide lixiviant in the alkaline media, or aqua regia, followed by the further recovery process using activated carbon adsorption or cementation with zinc, iron or aluminum plate or powder, though they both are quite effective recovery processes, if considering the special requirements on safety and ecofriendliness for the modern hydrometallurgical processes, various improved or novel extraction processes are greatly demanded [2]. Recently, the biosorption technology applied to the recover precious metals in the hydrometallurgical process has become a concern [3,4]. Inoue’s research group made great progress in the recovery of precious metals such as gold, palladium and platinum from the e-wastes such as spent mobile phone by using biosorption from the hydrochloric acid media [5,6]. This new hydrometallurgical process exhibits the prominent advantages of being cost-effective for its short process, easy operation and near-zero emission. In the above recycling process for e-wastes treatment, the preparation of biosorbents is the key and backbone of the whole recovery process. For this purpose, they developed a series of suitable sorbents for precious metals recovery by using the tanning-based or cellulose-based biomass such as persimmon peel, grape peel, orange juicing residue, waste cotton, waste paper through the crosslinking process with concentrated sulfuric acid and relative chemical modification processes [7-10]. In the present study, we also applied this technique to prepare the biosorbent of precious metal uptaking by using garlic peels as the raw materials, and investigated the adsorption properties of such-obtained gel in the hydrochloric acid media."

Jan 1, 2012

By Alain Jardy, Thibaut Quatravaux, Denis Ablitzer

"A numerical model of the Vacuum Arc Remelting process has been developed and applied to simulate remelting of various metallic materials, such as specialty steels, titanium and zirconium alloys. In practice, electromagnetic stirring is sometimes used, resulting in a complex 3D molten metal flow. After having validated the numerical model for different remelting conditions, we can use it to study the effect of applying a constant or alternated magnetic field on the thermohydrodynamic behaviour of the melt pool. The intensity of flow turbulence, computed with a classical k-E model, is shown to depend strongly on the nature of electromagnetic stirring.IntroductionThe principle of the Vacuum Arc Remelting (VAR) process, illustrated in figure I, consists in melting a consumable metallic electrode of the required grade under a high vacuum, in order to obtain a sound ingot of good structural quality.During remelting, an electric arc is maintained between the tip of the electrode and the top of the secondary ingot, in order to ensure melting of the electrode. The metal droplets fall through the arc plasma and progressively buid up the ingot, which solidifies in contact with the walls of a water-cooled copper crucible. The secondary ingot formed in this way contains three distinct zones, corresponding to the liquid pool, fully solidified metal and intermediate mushy zone. In order to stabilize the arc, it can be confined with the aid of a magnetic field created by an external induction coil. This field can also be used to stir the liquid metal, the rotation induced being in the orthoradial direction. By reversing periodically the coil current, stirring can be alternated."

Jan 1, 2004

By L. W. Beckstead

The use of acid ferric sulfate solution as a lixiviant for chalcopyrite concentrates has been of little interest from a practical standpoint due to the formation of a tenacious layer of elemental sulfur which severely impedes the reaction progress. CuFeS2 + 4Fe+3 ?Cu+2 + 5Fe+2 +2s° For example, an acid ferric sulfate leach of chalcopyrite concentrate results in only 12% copper extraction in a three hour leach at 93°C. Experimental results suggest that particle size is the only controllable variable which has a significant effect on the rate of acid ferric sulfate leaching at ambient pressure. Size reduction of the concentrate prior to leaching was exam¬ined using various methods of grinding. Of the grinding methods considered, attrition grinding was found to be the most effective. Leaching of an attritor-ground product (median particle size 0.5 microns) resulted in approximately 90% copper extraction in a three hour leach at 93°C. Energy measurements suggest that the costs associated with attrition mill¬ing are not unreasonable. Evidence indicates that "activation" or stored strain energy is not responsibile for the enhanced reaction kinetics of the finely ground concentrate, but rather the experimental results can be explained simply in terms of the increased surface area due to size reduction. Leaching reaction mech¬anisms operative in the acid ferric sulfate system are discussed and the application of ultra-fine grinding technology to other systems is considered.

Jan 1, 1976

By Tracey Brommer, Britt Elin Gihleengen, Elsa Olivetti, Randolph Kirchain

"Increased demand resulting from the economic and environmental advantages of recycling secondary materials has constrained secondary material supply. As a result of constrained supply, the conventional strategy to maximize recycled content in an individual aluminum alloy must be expanded to maximizing total recycled content in a given production period. This work compares the performance over a two week period of an actual remelter for two strategies; a sequential charge-by-charge optimization framework and an integrated approach that explicitly incorporates the production schedule. Optimizing across the entire two week production is found to increase recycled content and minimize primary and alloying material additions. It is expected that as the scrap material market continues to be constrained by high demand, longer term batch planning strategies that can optimize material allocation will deliver improved performance.IntroductionIntensifying economic and environmental pressure to incorporate secondary aluminum into products is pushing remelters to explore additional strategies and tools to increase recycled content. Aluminum remelters are exploring alternative sources of secondary materials because of constrained secondary material supply and relatively high primary and secondary material cost [1]. Computational models, such as blending models are a tool that could help industrial remelters mitigate supply and cost challenges and thereby increase recycled content. In particular, computational tools can help manage the incorporation of new raw materials of variable quality. Blending models find many industrial applications and have been explored for over sixty years originating with the classic nut-mix problem dating back to 1950’s [2]. Blending models optimize the raw material input to make a desired product subject to a series of constraints such as product specifications and material availability. Deterministic and linear blending model formulations are presently implemented in some industrial aluminum remelters [3]. The primary reluctance of aluminum remelters against computational model implementation is the incapability of their blending models to reflect the intricacy of industrial remelting conditions [4]. For example, to reduce calculation time, industrial aluminum blending models usually optimize a batch plan for a single alloy and are not formulated to optimize several products simultaneously. Since such a model does not include knowledge of subsequent charges in the optimized batch plan, the resulting batch plans tend to deplete the “cleanest” secondary materials leaving the more uncertain and compositionally challenging materials for later charges. As a result, a remelter may override the calculated batch plan or leave certain scrap materials out of the material input to conserve these materials for alternative products scheduled for later production. This work explores an alternative aluminum charge planning tool that can optimize across an extended production schedule and compares it to a heuristic sequential optimization strategy reflecting an industrial remelter."

Jan 1, 2012

By Rodney L. Williamson

Vacuum arc remelting (V AR) is an industrial metallurgical process widely used throughout the specialty metals industry to cast large alloy ingots. Part of the V AR control problem consists of adjusting arc current to control electrode melt rate which also depends on the electrode temperature distribution. Because the temperature distribution responds very slowly (1-4 hours depending on size and material) to changes in melt power, the melt rate response is history dependent and highly nonlinear. The situation is complicated further because measurement of the electrode temperature distribution is not practical. To solve the problem of accurate, responsive melt rate control. a low order electrode melting model has been developed and incorporated into a V AR process controller. Data from laboratory and industrial tests show that the goal of responsive, accurate melt rate control has been achieved, even when melting under highly dynamic process conditions. Keywords: Vacuum Arc Remelting. Model-Based Control

Jan 1, 2003

By William J. Mallio

Substantial differences between in situ and conventional technology require that in situ ore grade be established for deposit as distinct from the total contained metal value. Establishing an in situ ore grade involves determining the fraction&apos; of the contained metal that can be leached by the fluid. This depends on the proportion of the ore minerals that occur on fluid flow paths as defined by the permeability distribution. Mechanisms involved in the in situ mining of sulfides are: oxidation of the sulfur, solution of the metals, complexing of the released metals, and a transport to a recovery point. Metal ions may be delayed or lost due to inefficiencies in these pro-cess steps or by reactions of the metal ions in solution with the rock. These reactions can involve precipitation of new phases, exchange of the metals of the interest with Ca or Na in clays or zeolites, retention of metals in oxidized mineral grains, or secondary enrichment of other sulfides along the paths of the solution flow. The efficiency of solution of metals and potential loss or delay mechanisms are controlled by local equilibria (the Eh, pH conditions) present in different parts of the ore zone. Permeability distribution in the rock mass and the coincidence of ore minerais with flow channels must be determined before a deposit can be judged suitable for in situ mining. Laboratory studies indicate that the natural permeability system is dependent on the degree of cementation of veins by late generation hydrothermal activities. The major conclusions of the study are:, 1. Deposit selection is critical; suitable deposit types include deep lying sedimentary deposits, selected zones of porphyry systems and vein controlled hydrothermal deposits; 2. Adequate laboratory and geochemical analyses should be undertaken through quantitative petrographic study and permeability mapping; and 3. Economic incentives for in situ mining must consider limitations of recovery caused by inefficiencies in dissolution and transport associated with particular deposits.

Jan 1, 1981

By Daniel E. Groteke

This paper describes a new technology which allows aluminum drosses to be processed at the generating melting furnace to recover available metallic values. The systems, offered in both manual and automatic modes, are capable of processing quantities ranging from 15 to 200 lb. per cycle, and recovering up to 90% of the aluminum with a combination of agitation and chemical reactions. In the automatic mode, the separation of molten alloy and de-metallized dross is achieved in less than five minutes process time. The recovered alloy, of largely unchanged composition, may then be returned while at elevated temperature to the original melting furnace to achieve an additional saving of energy.

Jan 1, 2000

By Y. Prévost

The Noranda Continuous Converting Process was commissioned in November 1997 at the Home smelter in Rouyn-Noranda, Quebec, Canada. It has completed over 18 months of successful operation. Excellent team work and technical expertise contributed to achieve targeted production levels and environmental goals after only a few months of operation. The operating results have demonstrated the flexibility of the process in producing blister copper from a variety of copper feed materials including a combination of molten and solid copper matte, reverts and fluxes. This paper describes the startup activities and process optimization tasks performed during the first year of operation of the new Noranda Converter.

Jan 1, 1999