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By E. C. T. Chao

Micro-optical and synchrotron radiation-induced X-ray fluorescence (SXRF) techniques have been used to study unoxidized and oxidized samples of Carlintype sedimentar,y rock-hosted disseminated gold ore. In these samples, Where much of the gold is submicroscopic, the SXRF technique, which has a spatial resolution of about 20 ~m and a minimum detection limit (MDL) in the ppm range, is an ideal and necessary tool for precisely locating gold-rich areas in a sample. Gold-rich areas pinpointed by SXRF were later studied in detail by micro-optical methods, principally optical microscopy and scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX). In two unoxidized and one oxidized ore samples, SXRF analyses have shown gold to be present predominantly in discrete clay-rich and silicified areas. Gold was not detected by SXRF in association with pyrite or carbonaceous materials. SEM-EDX examination of the gold-bearing areas in the unoxidized samples succeeded in identifying only two free gold particles, 0.2 and 0.5 ~m in size. In the oxidized sample, gold particles appear to be larger (but still submicroscopic) in average size and more evident in micro-optical examination after SXRF location of goldbearing areas. The findings of these studies may help to improve the efficiency of processing and recovery of gold from unoxidized ores.

Jan 1, 1987

By Jitka Jandová

In this study, hydrometallurgical processing of waste ZnO flue dust arising during zinc removal from galvanized low-alloy steel sheets was investigated on a laboratory-scale to obtain electrolytic zinc. The flue dust was separated from flue gases, generated during heating waste galvanized steel sheets in an electric furnace under air atmosphere at temperatures of about 1000oC. The dust, comprising tetragonal ZnO and insignificant amounts of SiO2, was contaminated by Fe, Mn, Pb, Al, Mg, Pb, Cu and Ca. The dust was leached in 0.5 and 1.0M H2SO4 and/or in 20 and 30% NaOH at different temperatures and different liquid-to-solid ratios to determine the optimum conditions leading to the highest possible selectivity of leaching and efficiency of Zn extraction in minimum time. The subsequent electrowinning process was performed with refined zinc sulphate leach liquors and/or with untreated zinc caustic solutions. Zinc sulphate leach liquors were purified using a combination of a hydrolytic pH-controlled precipitation, cementation and carbon refining. Effects of operational variables on Zn electrowinning have been studied for both sulphate and caustic electrolytes. The conventional plate-plate electrowinning cell has been explored in this study. Comparison of results obtained for both zinc electrowinning from acid sulphate and alkaline solutions is presented contribution.

Jan 1, 2003

Hazardous waste has often very complicated chemical compositions in a variety of physical forms and is normally processed in rotary kiln incinerators. Due to large variations in waste types and difficulties in feed characterization, the complex transport processes within the incinerator are not well understood, and the incineration process meets challenges in a smooth operation, and expects various uncertainties in the process chemistry and emission control. For better understanding of the incineration process, simulation was carried out by using Computational Fluid-dynamics (CFD) to characterize temperature and species distribution in the incinerator. In order to catch certain aspects of thermal and chemical behavior, a novel approach is proposed to represent approximately the waste streams and the subsequent combustion process. Hazardous waste in various forms from an industrial-rotary-kiln waste incinerator is firstly converted to a hydrocarbon-based virtual fuel mixture with approximately the same HIC molar ratio and calorific value. The simulation of the combustion process of the simplified hazardous waste was proceeded with a combustion model. The distribution of temperature and chemical species especially the remaining CO in the system is preliminarily investigated. Distribution of CO concentration, as a good indicator of emission level for the incineration process, could be used to evaluate the emission control. The predicted temperature distribution has been compared with available measurement data from an operating rotary kiln waste incinerator at A VR-Chieme, in the Netherlands. Reasonable agreement has been reached between the measured and predicted temperature data. [n the next step, measurement of species distribution in the system is planned to further validate the combustion model.

Jan 1, 2003

Hazardous waste has often very complicated chemical compositions in a variety of physical forms and is normally processed in rotary kiln incinerators. Due to large variations in waste types and difficulties in feed characterization, the complex transport processes within the incinerator are not well understood, and the incineration process meets challenges in a smooth operation, and expects various uncertainties in the process chemistry and emission control. For better understanding of the incineration process, simulation was carried out by using Computational Fluid-dynamics (CFD) to characterize temperature and species distribution in the incinerator. In order to catch certain aspects of thermal and chemical behavior, a novel approach is proposed to represent approximately the waste streams and the subsequent combustion process. Hazardous waste in various forms from an industrial-rotary-kiln waste incinerator is firstly converted to a hydrocarbon-based virtual fuel mixture with approximately the same HIC molar ratio and calorific value. The simulation of the combustion process of the simplified hazardous waste was proceeded with a combustion model. The distribution of temperature and chemical species especially the remaining CO in the system is preliminarily investigated. Distribution of CO concentration, as a good indicator of emission level for the incineration process, could be used to evaluate the emission control. The predicted temperature distribution has been compared with available measurement data from an operating rotary kiln waste incinerator at AVR-Chieme, in the Netherlands. Reasonable agreement has been reached between the measured and predicted temperature data. In the next step, measurement of species distribution in the system is planned to further validate the combustion model.

Jan 1, 2003

By Richard L. Summers

The shaped charge has proven in various military and industrial applications to be an effective penetrator of materials. Upon initiation a detonation wave traverses the explosive billet, collapsing a metallic liner and creating a jetting process. From multiple non-simultaneous flash radiographs of the jet in free flight, the observer can study the collapse, formation, and growth of a shaped charge jet. Digitization of a particulated jet's position and shape from the radiograph into electronic storage files provides the experimentalist with an efficient basis for data reduction. With the aid of a simple personal computer, one can in a matter of minutes generate a wealth of information concerning jet formation after initiation and thus gain insight into the quality of its manufacture, design, and assembly. This paper will in detail explain the methods in place for fully automated data reduction of radiographic films. Methods of computer aided digitization of particulated jets and analysis of physical jet characteristics and performance will be discussed.

Jan 1, 1992

By Joo Hyun Park, Kyu Yeol Ko

The viscosity of the CaO-SiO2-xMnO-yCaF2 slags (C/S=1.0; x=10, 40%; y=0 to 15%) was measured to clarify the effect of CaF2 on the viscous flow of molten slags at high temperatures. Furthermore, the Raman spectra of the quenched glass samples were quantitatively analyzed to investigate the structural role of CaF2 in a depolymerization of silicate networks. The critical temperature of the slags abruptly increased at 15%CaF2, which was confirmed to originate from a crystallization of cuspidine using XRD analysis. The viscosity of the slags continuously decreased by CaF2 addition in the 10%MnO system, whereas the viscosity of the 40%MnO system was not significantly affected by CaF2 addition. The effect of CaF2 on the viscosity of the slags was quantitatively analyzed using micro-Raman spectra of quenched glass samples accompanying with a concept of silicate polymerization index, Q3/Q2 ratio. A polymerization index continuously decreased with increasing content of CaF2 in the 10%MnO system, whereas it was not affected by CaF2 in the 40%MnO system. Consequently, the bulk thermophysical property of the CaO-SiO2-MnO-CaF2 slags was quantitatively correlated to the structural information.

Jan 1, 2014

By H. J. Garcia

Biodegradation of cyanide by microorganisms isolated from solids previously exposed to cyanide has been investigated. Initial sodium cyanide concentration was 300 ppm at pH 10.5. The kinetics of biodegradation were found to be first order with respect to cyanide concentration, and the overall reaction rate constant is k = 0.102 day-1. The activation energy and the frequency factor were determined to be { A }Ea = 5.45 Kcal/mol and A = 1.28 x 10-2 sec-1, respectively. Based on these values, thermodynamic properties of an intermediate activated complex were assessed. All tests resulted in cyanide concentrations less than 0.1 ppm in about 35 days at 250C, whereas at 350C the time of biodegradation to reach this cyanide level was 30 days. Kinetic data were also established to relate biodegradation to amount of inoculum. The maximum theoretically-attainable rate, Vm , and the optimum amount of inoculum, K , were determined to be 4.8 x 10-4 M NaCN/day and 7.5 % of amount of inoculum. With respect to the mechanism of biodegradation, cyanide was shown to decompose to carbonate, bicarbonate and ammonia. Titrimetric analyses revealed concentrations of 5.6 x 10-3, 4.8 x 10-3 M, and 70.2 ppm for carbonate, bicarbonate and ammonia, respectively. The average cell population was determined to be 3.75 x 108 cells/mL.

Jan 1, 1994

By M. Urda-Kiel

Stainless steel is increasingly used as a cathode starting sheet. It was shown earlier that even when depositing copper on copper, a substrate-influenced zone appears in the deposit structure, followed by a transition zone and finally by the electrolysis-influenced structure. On copper, the substrate-influenced zone has a thickness of twenty micrometers and on titanium, eventually more than fifty micrometers. Initial nucleation and growth have a considerable influence. In this paper, copper was deposited in a channel cell on four different 304 stainless steel substrates: mechanically polished and anodized, respectively, at 0, +400 and +800 mV/SHE in 1M H2SO4 at 20°C. Copper was deposited under electrowinning conditions after solvent extraction (SX) (40 g/l Cu++, 180 gh/l, H2SO4, 20 or 60°C). The results showed that, although Auger surface analyses of the substrates were only slightly different one from another including the oxide thickness, nucleation and initial stages of growth were very sensitive to the surface treatment of the substrate. Potential step and current step methods gave similar results : progressive nucleation followed by 3D diffusion controlled growth. The highest nucleation frequency was observed on stainless steel anodized at 0 mV/SHE, under various electrolysis conditions. The potential influence of these findings on industrial practice is discussed.

Jan 1, 1999

By J. P. Ibáñez

The uptake of copper from extremely dilute aqueous solutions by alginate in the form of protonated dry alginate beads was investigated. Barium was used to cross link the alginate forming the beads. The effect of various experimental parameters such as pH and metal ions concentration on the uptake of copper were studied. The uptake was strongly dependent on the Cu-bearing solution pH up to a value of 4.5. A removal of 100% o was achieved when the initial concentration of copper was as low as 8.0 mg/L. The maximum uptake, i, e., the loading capacity, was found to be 167 mg of copper per g of beads. The mechanism governing the removal of copper was found to be ion exchange between protons of the alginate beads and cupric ions of the solution. For this ion exchange process a molar ratio, d[H+]/d[Cu2+], of 2.0 was determined. EPMA-EDX analysis of the Cu-loaded beads showed a uniform distribution of the ions throughout the structure of the alginate, regardless the solution pH. This may suggest that this sorbent material is a porous ion exchanger having high permeability and capacity. The uptake of copper and of the heavy metals cadmium and zinc by this sorbent is compared.

Jan 1, 1999

By Keizo Uematsu, Satoshi Tanaka, Zenji Kato, Nozomu Uchida

"A novel technique is developed and applied to evaluate the binder segregated at the· surface of granule. Compressive strength of each granule was measured directly with a micro-compressive instrument. The relation between compressive characteristics and the amount of binder was discussed quantitatively.IntroductionCharacterization of granules is essential in the production of ceramics, since they govern the structure of green compact and thus the structures and properties of ceramics. However, there is no research to clarify the relation between the strength of granules and structure of granules, especially of binder segregation at granule surface. We develop a novel technique to determine the binder concentration in the granules by the iodine method. In this study, we measure yield strength of granules directly and discuss the relevance between compressive characteristics and the concentration of binder.ExperimentalGranules were prepared by spray-drying of aqueous slurry of commercial alumina (AL160-SG1. Showa Denko, Tokyo, Japan) and PVA (PVA 105 Kurare, Japan). PVA. concentration in granules was 1.1, 1.5 and 2.3 wt%. The inlet and outer air temperatures were 200 and 95 °C , respectively. Iodine-potassium iodide solution was prepared by dissolving iodine (0.15mol) and potassium iodide (0.15mol) in diluted water (50ml). A saturated boric acid solution was prepared by mixing boric acid powder with a diluted water."

Jan 1, 2000

By Steven Wright

BHP Billiton?s Olympic Dam copper flash smelter employs the direct to blister process for smelting high grade copper concentrates. SO2 evolution during tapping gives rise to safety concerns. A thermodynamic model for the blister copper (Cu-Fe-S-O) was used to predict the volumes of SO2 evolved. The Multiple Phase Equilibria Model (MPE) was used to evaluate the slag chemistry inside the furnace. The blister copper model was used to explore the relationship between %S and %O in the copper and the amount of SO2 evolved on cooling. The volume of SO2 evolved was sensitive to the O content with reduction to levels below 0.2 ? 0.15% likely to suppress SO2evolution on cooling. Concentrations of S and O in copper samples from trials generally lay above the equilibrium line calculated for an average temperature of 1275C and a partial pressure of SO2 of 1 atm. Consequently there is a thermodynamic driving force for SO2evolution when cooling to this temperature during tapping. A number of potential process options to suppress SO2 evolution on tapping were investigated thermodynamically. Some of the options require treatment of the blister in a forehearth or separate furnace, while others impact on current practises in the flash furnace with slag present. The opportunities that these options present are discussed.

Jan 1, 2006

By I. A. Ibrahim

Ilmenite, in its natural form, is an inactive mineral from which the selective removal of iron is rather difficult. The reactivity of ilmenite. so that it can be leached with dilute hydrochloric acid, can be enhanced by chemical reduction in solution using a suitable metal as a reducing agent. The present paper aims at the evaluation of an Egyptian ilmenite ore for the production of synthetic rutile by direct leaching with hydrochloric acid in presence of iron powder. In this process, the titanium and iron contents are dissolved; meanwhile, the dissolved titanium is hydrolyzed and re-precipitated leaving mainly iron in solution. Leaching conditions were optimized to obtain less iron in the final solid product. Addition of sufficient amount of iron powder during leaching reduces the dissolved Fe3+ to Fe2+ and reduces the dissolved Ti4+ to Ti3+. The creation of Ti3+ in solution is assumed to have a role in dissolving the ferric iron and hence increasing the reactivity of the ilmenite ore. Synthetic rutile of about 90% TiO2 and 0.77% Fe2O3 was obtained from ore with a grain size 100% passing 200 mesh and a 5-hour leach time with 20% HCl at boiling temperature (110°C) and 0.11 g iron powder / g ore.

Jan 1, 2003

By G. Bjorling

After complete dissolution of chalcopyrite concentrate in sulphuric acid in presence of nitric acid the excess of the latter is expelled by a surplus of concentrate and the last traces of nitrate removed in the mother liquor after crystallization of the copper and iron sulphates. Zinc accumulates in the mother liquor from which it can be removed by solvent extraction of zinc sulphate as a pair of ions. After dissolution of the sulphate crystals in water the neutral solution is oxidized in an autoclave at 140°C where iron sulphate is thermally hydrolyzed; the iron-free solution is taken to copper electrowinning and the cell acid after partial evaporation recirculated with the mother liquor to the leaching circuit. Total recovery of copper is about 96%; other metals like zinc and iron are concentrated in industrially usable products. At a copper price of about 70 c/lb, the method appears to be profitable also in a small unit.

Jan 1, 1976

By Tiejun Chun, Jian Pan, Deqing Zhu, Vinicius Mendes

"Fine manganese fines are characterized by large amount and low price compared to lump manganese ores. However, fine manganese must be agglomerated as EAF (electric arc furnace) feed. In this paper, high quality fired pellets were produced by simulating grate-kiln process to supply the feed for EAF from some imported manganese ore fines containing high combined water. Manganese ore fines assaying 44.47wt%Mn, 5.89wt%Fe, 12.09%LOI and with 72.7wt% ranging between 0.5mm and 8mm, are pretreated up to the particle size of 84.7wt% passing 0.074mm by HPGR (high press grinding roller) twice in open circuit. The finely ground manganese fines were mixed with 1.2wt% bentonite, balled at 15% moisture for 7min in disc pelletizer. The drop numbers, compressive strength and thermal shock temperature of green balls reach 11 times/0.5m, 11 N/pellet and 360oC, respectively. After the green balls drying in the oven, the dry pellets were preheated at 1050oC for 12 min and then fired at 1300oC for 12 min in electric tube furnace. The compressive strength of fired pellets reaches 2621 N/pellet. Therefore, these pellets are high quality burden for blast furnace or EAF due to high mechanical strength and high Mn grade of 49.11wt% and low detrimental elements.IntroductionManganese, mainly using as deoxidizing agent, desulfurization agent and alloying elements, is widely used in the steel company. With the rapid development of iron and steel industry in China, domestic manganese ores cannot meet the requirement, resulting large quantities manganese ores import to China [1-4]. Compared to lump manganese ores, fine manganese ores containing high combined water are characterized by large amount and low price. However, they must be agglomerated as EAF (electric arc furnace) feed. There are three ways to agglomerate the manganese fine ores, sintering, briquetting and pelletizing [5-6]. Compared to the other two methods, pelletizing technology possesses the following superiorities, such as uniform size distribution of product, stabilizing chemical composition of product and lower energy consumption in producing. Therefore, pelletizing is a superior way to treat the fine manganese ores [7]. The systematic research of producing manganese oxide pellets by fine manganese ores containing high combined water was studied in this paper."

Jan 1, 2011

By Kurt Westerlund

Three years operating experience of the FLUXFLOW waste heat boiler (WHB) 20.000 nm3/0h at Boliden Rönnskär Sweden on a TBRC smelting galena (PbS). Operating experience from the Kivset flash WHB 11.900 nm3/h at Samim, Porto Vesme, Sardinia, Italy. Conceptual features of the 93.600 nm3/h FLUXFLOW (WHB) on the Isasmelt smelting in melt furnace for 180.000 t Cu/a at Mount Isa, Australia.

Jan 1, 1992

By Merete Tangstad, Lars Klemet Jakobsson

"Slag refining is a promising refining method for boron removal from silicon as a part of a metallurgical route for production of silicon for solar cells. There is, however, limited data on the distribution of impurity elements between silicon and different types of slags. In the present study, the distribution of boron and calcium between silicon and slag were determined at 1600 °C for calcium silicate slags with a CaO/SiC>2 ratio between 0.65 and 1.3. An almost horizontal linear trend was found for the distribution of boron between silicon and slag, and the borate capacity was found to follow the relationln(CB0, ) = 30.8 + 2.96-V (1)where V\s the CaO/SiCh mass ratio within the range of the experiments.IntroductionSolar grade silicon feedstock contributes significantly to the total cost and energy required to make crystalline silicon solar cells. A less expensive and less energy requiring method of solar grade silicon production is therefore needed in order to make crystalline silicon solar cells more viable as an energy source. Silicon is an abundant element and the manufacturing cost of solar grade silicon is therefore mainly determined by costs related to purification of metallurgical grade silicon. The Siemens process is the most common process today, but it is an expensive and highly energy requiring process that gives silicon with a higher purity than is needed for crystalline silicon solar cells. A cheaper and less energy requiring method for production of solar grade silicon can either be achieved by modifying the Siemens process or by using a new production method. Purification of metallurgical grade silicon through a metallurgical route is a promising method that is already in use industrially. It has however proven to be hard to lower the boron content to 0.3 mg/kg or less, which is the requirement for most p-type crystalline silicon solar cell manufacturers. Slag refining is seen as one of the most promising approaches that can be used to bring down the boron content to the required level, but there is not much data on how boron is distributed between silicon and binary calcium silicate slags [1-4]. The distribution of boron between silicon and calcium silicate slags at 1600 °C has been studied in this work, and the obtained data has been used to calculate the borate capacity of binary calcium silicate slags."

Jan 1, 2012

By T. A. Chepushtanova, B. Mishra, E. O. Kilibayev, V. A. Luganov

"The paper contains the results of studying about modification of pyrite and arsenopyrite specific surface and porosity at their thermal decomposition. The studying of specific surface was carry out by B.E.T. – adsorption of nitrogen at his boiling-point. In our work were using the electron-microscopical, X-ray structure analysis and chemical analysis. There was established that the decomposition of pyrite and arsenopyrite accompany by increasing of pores volume from 0.303 · 10-3 to 1.23 · 10-3 at increasing of pyrite degree of decomposition about 41 % and then decrease about 0.131 · 10-3 m3/g at degree of decomposition near 100 %. The surface area of pores increase from 0.31 to 1.085 m2/g with following lowering due to enlargement and confluence of minor, small pores. Increasing of porosity accompany with increasing of particles windage that appear the result of heightened dust-furnace partially decomposing pyrite and arsenopyrite particles by air flow from furnace reaction zone. This explains heightened contention of sulfide sulfur in roast dust of sulfide concentrate. 1. INTRODUCTION As a result of ore base exhaustion of ferrous and nonferrous metallurgy at metallurgical treatment are involving more complicated and less qualitative ores. Magnetiting ores content considerable quantity of pyrite complicative the technology of iron extraction. At the same time the pyrite concentrates wining at dressing content different nonferrous metals in industrial quantities. Extracting ores of nonferrous metals are contenting considerable quantity of arsenic at the present time. Extraction of base metals from complicated raw materials demands new technologies. Arsenic contenting in ores is necessary to utilize (waste burial) in more ecological compatible form. Arsenic on acting metallurgical and chemical enterprises from technological cycle is withdrawing in the form of arsenate – arsenite cakes, burial of their may lead to seriously ecological problems as times goes by. In Kazakh National Technical University is carry out the cycle of researching by pyrite, arsenopyrite and arsenate – arsenite cakes treatment with the object of arsenic withdrawal in sulfide form – in more ecological and safe form and with the object of preparation of initial ore raw materials to following pyro- and hydrometallurgical treatment. As a result of sulfidizing of arsenate – arsenite cakes by pyrite are forming the volatile arsenic forms and pyrrhotite of variable structure."

Jan 1, 2008

By Bien Ferrer

In most smelting operations, there is a strong incentive to improve safety, reduce downtime and extend the campaigns of furnaces and related equipment. An asset management strategy that is based on information, rather than simple throughput metrics and intuition, can be developed to improve uptime and unlock value currently unrealized at existing smelters. Advances in digital technology, including data analysis, modelling and monitoring for hot pyro-metallurgical vessels, make it possible to assess the current condition of an asset, as well as to make more informed projections about its future condition, using on-line and historical data. This would allow practices around asset management to be more proactive and less reactive, with the end-result of optimized uptime. ‘Digital Asset Management’ describes a concept in which digital technology is used to support an asset management strategy and accelerate decision-making by providing information on what, why and how an asset should be designed, operated or maintained. With the overall goals of effective resource utilization, optimized operations, capital efficiency and social acceptance, Smelter 4.0 is a program of holistic improvement and is underpinned by the effective use of data to drive decisions. This paper focuses on Asset Reliability, which is one of the improvement pillars of Smelter 4.0, and introduces a methodology that is aimed at closing the gap between recorded data and evidence-based decision-making through Digital Asset Management.

A novel process is being developed for metal recovery from waste electrical and electronic equipment involving a leach reactor coupled to an electrochemical reactor. Metals such as Ag, Au, Cu, Pb, Pd, Sn etc. are dissolved from shredded electronic scrap in an acidic aqueous chloride electrolyte by oxidising them with aqueous dissolved chlorine species. In the electrochemical reactor: (i) chlorine is generated at the anode for use as the oxidant in the leach reactor, and, simultaneously, (ii) at the cathode, the dissolved metals are electrodeposited from the leach solution. The extended Butler-Volmer equation was used to provide predictions of the electrode potential dependences of partial current densities and, hence, total current densities, current efficiencies and alloy compositions for acidic aqueous chloride electrolytes containing Ag(I), Au(III), Cu(II), Pb(II), Pd(IV) and Sn(IV) species, together with dissolved chlorine. With judicious choice of kinetic parameters, the predicted total current density ? electrode potential behaviour of such solutions was in good agreement with experimental data for a rotating Pt disc electrode. Reduction of dissolved chlorine at a Pt rotating disc electrode exhibited mass transport controlled behaviour, in agreement with Levich?s equation over the potential range 0.3-0.9 V (SHE). This could form the basis of a linear sensor, possibly using a microelectrode for measurement and control of the dissolved chlorine concentration in the efflux of leach reactors and inlet to electrowinning reactors in the envisaged process.

Jan 1, 2003

By V. Baltazar

The behaviour of arsenic and antimony during copper electrorefining was studied in order to identify the conditions under which good quality copper cathodes could be produced from anodes with high levels of these impurities. Examination of the effect of current density over the range 21 to 37 mA/cm2 indicated that the relative amounts of As and Sb entering the electrolyte affected the onset of passivation. When the ratio of As/Sb entering the electrolyte was greater than 2, the anodes showed no sign of passivation even at the highest current density; when the ratio was less than 2, the anodes passivated at 37 mA/cm2. Cathode analyses showed that anodes with an As/Sb dissolution ratio less than 2.0 tend to produce cathodes of inferior quality even at normal current densities (25.7 mA/cm2). The criterion of a minimum As/Sb dissolution ratio of 2.0, and mathematical correlations for the distribution of As and Sb between the electrolyte and slime developed in a previous study, allow the calculation of the maximum allowable Sb level in en anode for a given As concentration. Analyses of plant data at the CCR Division of Noranda Inc. for the last four years of operation have demonstrated that the use of this as a quality control tool has allowed the quality of copper cathodes to be maintained despite a significant increase in the average Sb levels in anode receipts.

Jan 1, 1987