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By G. E. Agar, W. B. Kipkie

"This paper deals with the prediction of locked cycle flotation results from data developed from individual batch tests. A postulate is made that the distribution of material in a separation stage is determined by the chemical conditions and the flotation time and that this distribution can be characterized by split factors which are constants for a fixed set of conditions. With this premise, it is demonstrated that a steady state balance can be calculated for a circuit.Although the necessary equations can be solved algebraically, a computer program was written that uses an iterative tec1nique to arrive at the steady state balance. The program is written so that a variety of circuits can readily be simulated.A number of examples are examined to demonstrate the validity of this simulation procedure. The sensitivity of the material balance to changes in the split factors was examined. Data developed from different flowsheets is presented on sulfide ores, on copper-nickel separation and on silver flotation,"

Jan 1, 1978

By Sarah Bélair, Denis Beltrami, Deka Moussa Ragueh, Valérie Weigel

"Scandium is a highly valuable element belonging to the rare earth elements (REE) but it has different chemical and physical properties from those of lanthanides. This metal is generally used in aluminum-scandium alloys and in fuel cells but the development of its market is slowed down by its high price (more than 1000 US$/kg for a 99.0% grade product). Indeed, the low scandium content in the continental crust (an average of 22 ppm) and the difficulties to extract it selectively from solutions containing high impurity concentrations increase the cost of the recovery processes. Nowadays, scandium is primarily recovered as a byproduct.ERAMET is developing a hydrometallurgical process in Gabon (Mabounié) in which the scandium content in the deposit reaches 10 to 100 ppm. The Maboumine project consists in the extraction and purification of uranium, niobium, tantalum and REE from Mabounié ore. In the frame of this hydrometallurgical project, ERAMET had also studied the feasibility to recover scandium as a byproduct. During the ore leaching, uranium and rare earth elements including scandium are solubilized into the pregnant leach solution (PLS). Among the various methods investigated to recover scandium from the PLS, liquid-liquid extraction using Primene JM-T as extractant was chosen and tested first at laboratory scale and then at pilot scale. Selective stripping of the loaded organic was carried out by using phosphoric acid solution, allowing the selective recovery of scandium from thorium and zirconium partially extracted from the PLS by Primene JM-T under the process conditions."

Jan 1, 2016

By Haibin Wang, Zhiwei Huang, Zhixiang Cui, Wenzhao Cui, Zhi Wang

Fangyuan Two-Step copper smelting process was commercialized in October, 2015 and has been operating for 3 years and 5 months. As the unique continuous copper smelting process with simplified flow in the world, production parameters have been significantly improved after three years. In the first half of 2018, the feed rate was above 200t/h, availability reached 97.5%, operation cost was about 20% lower than the conventional three-step processes showing obvious economic advantages. The Two-Step process in Fangyuan is composed of 1 Submerged Lance Smelting furnace (SLS) and 2 Submerged Lance Converting& Refining furnaces (SLCR). Two SLCRs work alternatively to ensure continuous production. High grade and liquid matte from the SLS is introduced to the SLCR by sealed launder to complete converting and refining. The SLCR is an original and independent innovation of Fangyuan, for which Fangyuan completed lots of development and improvement. This paper will introduce the process and experience. INTRODUCTION China is the largest producer and consumer of refined copper. Most of the processes adopted in China are conventional "Three-Step" copper smelting processes, which are comprised of smelting, converting and refining. There exists some problems in the conventional processes, such as high energy consumption, large heat loss, low altitude emission of SO2, etc. To deal with these problems, Fangyuan developed the new copper smelting process with simplified flow, low cost, clean and high efficiency. The SLCR that combines converting and the refining process was also developed, which shortens the process flow from conventional three steps to two steps. The SLCR is of great significance in promoting the development of the copper industry. Development and industrialization of SLCR At present, copper concentrates are treated in three steps: smelting, converting and refining. Anodes are also produced by continuous converting processes such as the Mitsubishi process and the Double Flash process. Problems like matte transportation by ladle, capacity limitation, and low altitude pollution exist.

Jan 1, 2019

By Takashi Nakamura, Atsushi Iizuka, Yong Fan, Etsuro Shibata

Magnetic separation of precipitated magnetite as iron resources in copper slag is one of the potential effective ways to recycle the slag. It is preferable to convert molten fayalite slag after copper smelting process to magnetite slag via oxidation. With a TTT (Time-Temperature-Transformation) diagram, the crystal composition of the slag obtained after air isothermal oxidation could be estimated through a designed cooling path. The crystallization behaviors concerned with molten oxidation was studied for better understanding of the trade-off relationship between magnetite and hematite during molten heat treatment. Moreover, a brief consideration was implemented of the reaction mechanism.

Jan 1, 2014

By I. Orford, V. Rozon

"The Sä Dena Hes Joint Venture Mill was designed to process 450,000 tonnes per year of ore grading 11.3% lead and 13.2% zinc.Run of mine ore is crushed in a jaw crusher and then ground in a closed circuit SAG mill and ball mill. A standard differential float in conventional flotation cells produces quality lead and zinc concentrates. Dewatering of concentrates is achieved using high rate thickeners, lamella clarifiers and pressure filters. Process water is 100% recycle.Plant design was based on metallurgical test work performed on drill core samples. The plant is operating at better than design specifications.INTRODUCTIONSä Dena Hes Joint Venture was formed in 1989 to develop the Sa Dena Hes lead/zinc sulphide mine, located approximately 45 km north of the Town of Watson Lake, Yukon. The mine is owned by a Joint Venture partnership between the operator, Curragh Inc. (87.5%) and Hillsborough Resources Limited (12.5%).The project was completed in a record ten months, working throughout the severe Yukon winter and through an abnormally wet spring and summer. The first truckloads of concentrate were shipped from the mine on August 1, 1991.The mill currently processes 550,000 tonnes of ore per year grading 6.9% lead and 11.5% zinc. Ore is crushed in a jaw crusher and ground to 60% passing 75 microns in a closed circuit operation of one SAG mill and ball mill. Using conventional flotation cells a 150,000 tonnes of concentrate is produced in a year with lead concentrate grading 78% lead and a zinc concentrate grading 60% zinc at overall recoveries of 89% and 90% respectively.Concentrates dewatering is accomplished using high rate thickeners, clarifiers and pressure filters. The lead concentrate and zinc concentrate contain 5.4% water and 7.8% water respectively. Concentrates are trucked to Skagway, Alaska for subsequent shipping to overseas smelters."

Jan 1, 1993

By A. Fortin, C. Fréchette, M. Kreuh

Éléonore project is a gold ore processing plant at a mine site located near James Bay, Quebec, Canada. SNC-Lavalin was mandated by Goldcorp to perform EPCM services on the ore processing plant and permanent infrastructures of the project following an internal pre-feasibility study. The project incurred considerable challenges due to fast-tracking from a pre-feasibility to detailed engineering and construction. The paper reviews how the EPCM was carried out. Some of the challenges resulting from skipping the feasibility study stage are discussed. The paper also presents how multiple offices across Canada were used for the engineering design.

Jan 1, 2015

By E. L. Day

"In the early 1930s during the course of test work with a simple gold ore, it was evident that the time required to dissolve the gold by cyanidation was very much longer than should have been needed theoretically for the maximum size gold particles in the ore, A similar conclusion appeared to be valid for other gold ores. In a cyanidation system there are many factors which can influence the dissolution rate of gold, and a decision was made to investigate the more obvious variables, because a literature survey at the time showed that with the exception of the work of Yamazarki on the dissolution of silver in cyanide solution, virtually no attention had been given to this subject, Our work was not reported because the intention was to do this on completion of the Study, but owing to the demands on the Section's personnel for other work the investigation was never completed. Although other investigators have since studied the problem, the methods which we adopted and some of the conclusions may be of interest to metallurgists concerned with gold ore treatment.Form of GoldExperiments with gold ores were not possible because of the number of uncontrollable variables present in a gold ore-cyanidation system, therefore pure metal and reagents were used. Initially some experiments were carried out with gold leaf, but it was soon apparent that metal in this form was unsuitable because the uneven thickness of the leaf caused it to break up into pieces and. there was difficulty in determining precisely when complete dissolution had taken place, Numerous factors both expected and unexpected were found to influence considerably the results and much experimental work was necessary to establish the procedures which were finally adopted, Experiments were carried out with gold in the form of foil, wire, rings and sols. Finally, gold foil in the form of cylinders was adopted for most of the experiments although some work with gold in the sol form was included in the programme. Also some experin1ents were carried out with a gold ore to see if effects which were obtained with sodium chloride on gold sols were applicable to gold ores."

Jan 1, 1967

By Paul M. Lévesque

The Dome Mine has been in production for nearly 100 years and throughout the years many different mining methods were used to extract the ore. An exploration program late in the 1990s outlines new resources requiring the mine to extract the rock and some previously placed backfill (alluvial sand and/or classified tailings). It is therefore imperative to separate the backfill from the rock to reduce the negative impacts of handling the backfill on the ore pass, crushers and mill processes. Separating the backfill from the ore at the source would also reduce and/or eliminate the cost of handling this waste stream. The paper will touch on the backfill removal criteria, the risks, the alternatives and the selected method, screen decks, for backfill removal at the Dome Mine. The 155549 bulk zone case study will illustrate how the screen decks are in use at the mine. The paper will also illustrate how the lessons learned and conclusions of the work done for the 155549 bulk zone were applied to the second screen deck installation for the 257260 bulk zone.

May 1, 2009

By S. Shokri

The increasing size and complexity of mega construction projects result in having several geographically distributed stakeholders, collaborating with each other to successfully deliver the project. Electronic Product and Process Management Systems (EPPMS) are recently emerging to facilitate the collaboration between stakeholders, reduce the surprises and issues, and improve the project productivity. These are commercially successful but evolving systems. An important component of EPPMS is the Interface Management System, which aims at formalizing and automating the communication channels between stakeholders. An interface is generally considered the link between construction elements, phases, or stakeholders. An interface Management System (IMS) involves five iterative steps: (1) Interface Identification, (2) Interface Documentation, (3) Interface Transferring, (4) Interface Communication, and (5) Interface Closing. A fundamental part of step 2 is recognizing different roles in dealing with interfaces. Each stakeholder is assigned a different role, such as responsible, accountable, consulted, and informed. In a mega project, several thousands of interfaces exist with complex relationships between stakeholders. Therefore, identifying stakeholders with higher responsible roles has been requested as useful information to the project owner in dealing with some of the project risks. After the interfaces are determined, and the responsibilities are allocated, the critical stakeholders are identified using the centrality concept in Social Network Analysis. The critical stakeholders can be determined at the highest level, considering all types of interfaces, as well as for each specific type or discipline-related interfaces. The proposed methodology is applied on a hypothetical offshore project with over 500 interfaces. In fact, this project is a simplified representation of a real scale Liquid Natural Gas project. In order to reduce the complexity of calculations and clarity of explanations, the simplified case study is used. By implementing IMS in mega projects, different parties not only formalize the communication between each other, but also gain better visibility concerning their roles and responsibilities. In addition, the owner benefits from analysing the complex relationships between stakeholders to further identify critical ones, along with other criteria like package cost, stakeholders? experiences, etc.

Aug 1, 2013

By M. B. M. Monte, M. L. Torem, E. R. Pecanha, A. G. Merma

The recent literature has unveiled the potential use of microbial strains in mineral bioprocessing. This study presents the use of a Gram-positive bacterium (Bacillus subtilis) as bioreagent for hematite flotation. The bacterium presents the ability to modify the properties of mineral surface (electrophoretic mobility and hydrophobicity). It was studied the electrokinetic behavior of hematite particles, before and after the interaction with the bacterial cells. The results revealed a shift of the isoelectric point (IEP) of the hematite after interaction with bacterial cells, suggesting a chemical adsorption mechanism. Moreover, after bacterial conditioning, the zeta potential curve of hematite presented high values in the alkaline pH range. The hematite and the bacterial surfaces presented contact angle values around 27.4° and 41.0°, respectively. According to the results, the B. subtilis strain was capable of modifying the hematite surface, and after interaction the hematite surface presented a contact angle value around 46.0°. The flotation tests were carried out in a modified Hallimond tube. The experiments revealed a significant increase in hematite flotability using the Gram-positive strain as bioreagent. The tests pointed out a maximum recovery of hematite in the presence of 600 mg/L and pH 5. Therefore, the results from this study showed the potential use of the B. subtilis strain as a biocollector for hematite flotation, and its possible application in the mineral flotation industry.

Jan 1, 2016

By E. H. Chown

Scattered outliers of the Chibougamau Formation and the more continuous Mistassini and Otish Groups lie unconformably on an Archean basement abutting the Grenville Front. All the Aphebian rocks are deformed and offset by faulting related to the Front. The older Chibougamau Formation is exclusively elastic in origin, whereas the two later, time-equivalent groups include carbonatedominated (Mistassini) and elastic (Otish) sequences. Known syngenetic mineralization within these formations is limited to various radioactive showings in the Mistassini and Otish elastics, and the iron formations of the upper Mistassini Group. Three distinct types of epigenetic mineralization occur within the sedimentary rocks; pitchblende fracture fillings in all types of rocks in the Otish Group, widespread Mississippi-Valley type galenasphalerite showings at certain levels in the Mistassini Group, and chalcopyrite-pyrite bearing veins in or near argillaceous horizons of the Mistassini Group and Chibougamau Formation. The Otish elastic basin is part of a large area of the central Ungava peninsula which contains a variety of radioactive showings, the most promising being of the unconformity type, The final control for many individual showings appears to be local physico-chemical changes within faults and fracture zones. The overall structural control is in part supplied by the faulting episode related to the Grenville Front, which in turn limits the mineralization to the depth zone appropriate for open fracturing. The lead-zinc showings exhibit a strong stratigraphic control as well as close ties to secondary porosity developed by f aulting. The ore solutions were probably derived during the low grade metamorphism of the formations. Chalcopyrite- pyrite veins have provi ded the only mine production (Icon Mine) to date. They appear later than the low-grade metamorphic fluid circulation, and deposition is related to favourable structures and stratigraphy. The veins are clearly related to major faults. Thus, whereas stratigraphic settings appropriate to individual types of deposits are important, an overall structural setting may be demonstrated for a wide range of mineralizations. Detailed structural interpretations of individual showings may be the most fruitful pursuit in developing a concrete prospecting model.

Jan 1, 1984

By R. C. Urquhart

Since the first use of the electric arc furnace Henri Moissan (1892) and its use by Paul Hérholdt (1902) to melt steel, it has been successfully used as a pyrometallurgical smelting tool in the production of calcium carbide, iron, ferrous and non-ferrous alloys. Commercial forms of the electric arc furnace have evolved from round, single-phase single electrode units to rectangular three electrode three-phase units to round three electrode three phase units and ultimately to rectangular six electrode three-phase units. DC electrical supply has also been used to replace the three phase power supplies in some cases. This paper examines how these electric arc smelting furnaces have evolved in size, efficiency and configuration within the constraints of the smelting process, electrodes and electrical power supply equipment.

Jan 1, 2014

By Brian O'Hearn, Doug Hanson

"The most commonly used tendon supports in the Sudbury area include rock bolts, rebars, friction anchors and cable bolts. Due to the fact that these tendons are physically different and employ different anchoring systems they offer varying degrees of stiffness, yield ability, load capacity, anchor dependability and energy absorption. These differences coupled with variable rock mass and changing stress conditions have made it challenging to engineer the design of an effective support system. By tapping into the knowledge and experience gained by ground control practitioners, an empirically based rating system has been assembled that offers a guide to designers of support systems when choosing the most effective tendon support over a range of rock mass and stress conditions.A methodology referred to as support planning can be used to design support systems whose rehabilitation costs will be minimized. The use of multiple tendon types in anyone support layout is advocated, particularly when the stress state of the rock mass to be supported is expected to undergo a change."

Jan 1, 1995

By A. L. MacAllister

"Keymet Mine lies on the Elmtree River 4 miles west of Petit Rocher and about 18 miles northwest of Bathurst, Gloucester County, New Brunswick. A good gravel road runs through the property.The deposit was discovered in 1880 when a vein 7 to 8 feet wide was re-ported. In 1883 the first shaft was sunk as part of an exploration program which was carried out sporadically until 1897, when the company dissolved. Activity on the property was intermittent until 1946 when the property was again staked and during the next year diamond drilling intersected the vein in several places. In December 1949 Coulee Lead and Zinc Mining Company optioned the property and held it until its sale to Keymet Mines Limited in June 1952. By July of the same year work had begun on a three-compartment shaft.Early development work was concentrated on the 150, 300 and 450 foot levels but the shaft has since been sunk to I,228 feet to allow for eight levels at intervals of 150 feet. Little lateral work has been done to date below the 600-foot level.The first mill constructed to treat the ore was to go into production in the spring of 1954, but was destroyed by fire. A second mill, having a capacity of 200 to 300 tons a day, was officially opened October 25th, 1954. Present shipments are zinc and copper-lead-silver concentrates.The rocks of the area are shale, conglomerate, limestone, and quartzite with minor interbedded volcanic rocks, all probably of Silurian age. Small plugs of Devonian acidic intrusions occur 3 miles east and about 5 miles northwest of the mine. Minor dykes of both acidic and basic rocks occur on the mine property. In many of the fine-grained sedimentary rocks the more brittle laminre have been brecciated and give the rock the appearance of an argillaceous conglomerate."

Jan 1, 1949

By Michel Ruel, Ali Soltanzadeh, Benjamin Légaré

High fidelity commercial process simulation packages can be used at different stages of a greenfield project, from initial plant design to operator training in the later stages. However, there are several factors that make the software less attractive for small and medium size brownfield projects, such as the licensing cost and the fact-finding manpower required for model design and simulator maintenance. In this paper a different approach is described. The knowledge gathered from operating personnel was used to implement higher level models based on plant data, operating heuristics, and experience rather than detailed component-level models. The computing platform used was a low-cost, well-established, control system vendor-independent software. Throughout this paper we demonstrate the success of implementing this model-based approach using two industrial examples. The first example is a simulation of the carbon monoxide (CO) distribution system at a metallurgical complex. The purpose of this simulator was to test new control strategies and PLC programs prior to implementation. CO being a toxic combustible gas, validation of the suggested control system changes was necessary for plant safety. Simulation of specific operating conditions helped alleviate concerns and improved plant-wide acceptability of the new operating philosophy. The second example is a boiler simulator at a petrochemical plant. The operator training simulator (OTS) was designed as a platform for experienced operators to practice handling rare or abnormal conditions. A customized medium-fidelity model was developed for this targeted application where the cost of a full scale high-fidelity model could not be justified.

Jan 1, 2016

By Anne-Laure Bonnet

Les connaissances acquises au cours des dernières décennies sur les gîtes de métaux de base et précieux intensément métamorphisés (p. ex. Vokes, 1991; Cornell et al., 1992; Zaleski et Peterson, 1995) ont permis d?élaborer des guides d?exploration pour de tels gisements dans les terrains de haut-grade métamorphique (Spry et Scott, 1986; Rubin et al., 1993; Hand et al., 1994; Spry, 2000; Spry et al., 2000). Un transfert de ces connaissances à la cartographie des vastes terrains gneissiques non différentiés de la province de Grenville permet d?affiner l?approche cartographique nécessaire pour reconnaître les systèmes hydrothermaux métamorphisés en terrains vierges et peu diagnostiques puis d?en discriminer les divers halos d?altération (Corriveau et al.,1996, 1997, 1998, 2003; Williamson et al., ce volume). Cette approche prend en compte les « empreintes métamorphiques » observées sur le terrain, telles que les variations des assemblages minéralogiques, du mode et de la composition des minéraux métamorphiques, pour reconnaître des roches présentant une composition inhabituelle caractéristiques de protolites altérés par hydrothermalisme. Ces empreintes citées cidessus sont facilement reconnaissables dans les terrains de haut-grade où la recristallisation induit un grossissement des grains qui permet de déterminer la nature et le mode des minéraux dès les levés de terrain. Cette approche raffine la compréhension des terrains de haut-grade métamorphique et illustre que leur complexité (i.e. polyphasage de la déformation et du métamorphisme) n?est pas forcément une limite à leur exploration. Elle a donc été utilisée systématiquement lors des levés de terrain réalisés dans le cadre d?un projet de l?Initiative géoscientifique ciblée de RNCan. La zone cartographiée se situe le long de la marge sudest du Groupe de Wakeham dans le secteur est de la Province de Grenville. Deux régions ont été plus particulièrement étudiées, celle du lac Musquaro (SNRC 12K10, 11 et 14) et la région côtière comprise entre Kégashka, La Romaine et Baie des Loups (SNRC 12K1, 2, 3 et 7) (fig. 1).

May 1, 2003

By H. R. Manouchehri, A. Weh

"High voltage electric pulse comminution (SELFRAG) relies on inducing electrical breakdown that occurs when the resistivity of a dielectric is insufficient to completely block all transfer of electricity while the conductivity is not high enough to fully accommodate the flow of electricity without considerable changes to the crystal lattice. The technology is based on introducing the electrical discharges into solids immersed in water and placed between two electrodes. The technology has received significant attention since investigations have revealed the potential for fully fragmenting particles or pre-weakening rocks in order to reduce the energy consumption in comminution practices, improve liberation and potentially increase the recovery in mineral processing. Mineralogical analysis of samples showed possible liberation at coarser sizes by high voltage breakage in comparison with conventional mechanical comminution.This study explored the potential of implementing SELFRAG to treat the Sandvik’s Mittersill mine tungsten ore (scheelite) for recovery improvement. Accordingly, standard SELFRAG tests were conducted on four samples from the tungsten process plant to evaluate the energy-breakage relation and potential to liberate the value minerals at coarser size fraction for recovery improvement. The size reduction of the ore after processing with SELFRAG revealed that size deportment occurs at 0.4, 0.2, and 0.1 mm, which indicated potential liberation of gangue and target minerals at respective sizes. In comparison with conventional milling, the difference is the deportment of values into 0.4 mm sizes, which was, to some extent, confirmed by SEM liberation analysis. However, more tests are needed to proof the concept. The study has indicated that, despite consuming more energy in comparison with conventional mechanical comminution, there are promising prospects in liberating the values at coarser fraction and improve recovery by making use of SELFRAG. The energy consumption can be reduced through customized generator and equipment setup, which must be further investigated."

Jan 1, 2016

By Juergen Antrekowitsch, Stefan Steinlechner

"Waelz oxide from steel mill dust recycling is usually sold to the primary zinc industry, where it is first charged to the roasters to eliminate the remaining fluorides and chlorides. This limits the overall amount of secondary materials which can be used because of different operating problems in the roasters. Another option, in the case where the halides are low, would be direct leaching with low or medium concentrated sulphuric acid. Unfortunately, because of the carryover of some steel mill dust, iron is also present in the Waelz oxide, reaching contents up to 5 wt.%. Since the objective is to treat the solution more or less directly by electrowinning, with only a few simple preliminary purification steps, iron in the solution is a very important factor. Various trials have been done to investigate the dissolution behavior of the iron contained in the Waelz oxide. Although the zinc extraction should reach a maximum, all other elements, especially iron, should be low. This paper describes the results of our research in this area and offers possible options for Waelz oxide utilization. There is also a focus on how other elements, present in the material, influence the dissolution behaviour of zinc and iron, and whether a loss of zinc is unavoidable, if low iron dissolution is required.INTRODUCTION One of the most important secondary zinc resources is the zinc oxide originating from steel mill dust recycling. For the treatment of high zinc containing steel mill dusts, the Waelz kiln process is the so called “best available technology” and it dominates the industry, with roughly a 90% market share. The product Waelz oxide contains mostly zinc oxide, but it also contains lead compounds and halides due to evaporation with the zinc. In addition, it contains iron and some slag compounds due to mechanical carry-over. The presence of halides limits the use of the material as an alternative concentrate for primary zinc electrowinning. Such halides can be reduced to a certain extent by washing and/or solvent extraction (see following chapter). Although lead is not troublesome and theoretically represents a second recoverable valuable metal, iron is unwanted and causes additional problems during leaching. Even though Waelz oxide is generally a highly welcome input material in primary zinc metallurgy, due to its high zinc content, it still contains halides, and in the majority of cases, the oxide must first be treated in a roasting process. Different circumstances, like accretion formation because of the lead and halogen compounds as well as unwanted cooling effects in the roaster, limit the amount of Waelz oxide which can be substituted for the primary concentrate. Another, even more limiting factor, is the allowable concentrations of chlorides and fluorides in zinc electrowinning, the last step in the primary zinc processing route (Ruetten, 2011)."

Jan 1, 2016

By A. L. Hinde, H. Dong, J. T. Kalala

"The High Pressure Grinding Roll (HPGR) is gaining acceptance in the mineral processing industry and has become a competitive technology in reducing the specific energy consumption in Mineral processing plants. The amount of samples required for HPGR amenability testwork and HPGR wear tests is usually high and often cannot be available at early stage of projects were only a few drill cores are available.Although HPGR was initiated from small scale piston die compression tests, the development of small scale piston die test to predict the performance of HPGR has been slow.The objectives of this paper was to present the designs, operating procedure of piston-die press and operating conditions which have resulted in similar particle size distribution obtained from a piston die test and HPGR Labwal unit starting from the same feed size distribution. Testwork were conducted using a 2 MN piston-die press and a Labwal HPGR unit on major South African ore types, viz, gold, platinum and iron ores. The results obtained show that piston-die test can generate data to predict energy consumption, product size distribution, and even to evaluate the edge effect."

Jan 1, 2012

By Bradford C. Wesstrom

An overview of the challenges encountered at the Freeport McMoRan El Paso Copper Refinery with higher concentrations of antimony electrolyte will be shared. The observations will cover the detrimental effects on copper starting sheets, commercial cathodes and anode slimes. The study will show negative effects on quality and productivity. Experimental work will utilize a test cell to study the effects on electrolytes by different Antimony, Arsenic concentration and anode molar ratio. Best practices will be shared for producing high quality cathodes while effectively managing the detrimental effects of higher antimony electrolyte.

Jan 1, 2014