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By Michael S. Moats, Prashant Bagri

"In recent years with increasing concerns about energy consumption in hydrometallurgical processing, there is an ongoing attempt to use Catalytic Titanium Anodes (CTAs) for copper electrowinning. For this work, anodes with IrO2 - Ta2O5 coatings were prepared in the laboratory with the same total coating loading but varying the number of layers by changing the speed of withdrawal in dip coating. A second set of CTAs were fabricated on niobium, Ti Grade 1, Ti Grade 7 and Ti Grade 36 metal substrates. All the anodes prepared in the laboratory were characterized using standard electrochemical techniques and subjected to accelerated life testing. It was found that the coating would not adhere to the niobium substrate, the grade of titanium had a minimal to no effect on the life of the anode, and it is observed that as the coating speed slows, there is an increase in the electrochemically active surface area of the coating which seems to directly contribute to an increase in the Tafel slope of the anodes. There was inconclusive evidence on the effect of coating speed on anode lifetime.INTRODUCTIONLarge scale hydrometallurgical extraction of copper has become widely practiced over the last 40+ years. The hydrometallurgical route entails leaching, solvent extraction and electrowinning. With the increasing desire to process refractory sulphides like enargite and chalcopyrite through the hydrometallurgical route, use of hydro-processing of copper is expected to remain high.In conventional electrowinning, copper is deposited on the cathode and an inert anode is used for oxygen evolution. Presently, the most common anode material is rolled lead-calcium-tin and the cathode is 316L stainless steel (Robinson et al., 2013). This lead alloy is fairly inexpensive and is robust, providing lifetimes typically of 4+ years. The main drawbacks of lead alloys are their relatively high oxygen evolution overpotential, the need for cobalt in the electrolyte to reduce their corrosion, the contamination of cathode product by lead, and the generation of harzardous by-products (Hiskey, 1999)."

Jan 1, 2016

By R. S. Boorman, L. J. Surges

"Ore reserves at Brunswick Mining and Smelting totalled 101(106) tonnes grading 97 grams tonne-1 silver at the end of 1981. Silver is recovered as a byproduct in the copper, lead and bulk concentrates and is lost to the zinc concentrate and plant tailings. Recovery of silver for the year 1981 was 58,5%. The loss of potential revenue is in excess of Cdn $50(106) year-1 at current silver prices and milling rates.Silver is known to occur in solid solution in galena and as tetrshedrite. Evidence indicating the identity and significance of a third silverbearing mineral assemblage is reviewed and the distribution of silver losses is detailed. Characteristics of each the carrier which may be responsible for observed distribution, including size, surface quality, liberation and composition are considered, and the third carrier is shown to have possible implications for improved silver recovery by other Canadian producers as well as by Brunswick Mining.Silver tetrahedrite tailings distributed tailings and losses occur as coarse, free and as very fine unliberated galena in losses of the third carrier are between the zinc concentrate and are concentrated in the finest size fractions. Process alternatives for enhanced silver recovery by physical and chemical means are reviewed."

Jan 1, 1983

By M. Maeda, H. Sasaki

"Precious metals such as platinum, palladium, and rhodium are commonly used for automotive catalyst converters. To recover these metals with lower environmental load and cost, exposure to zinc vapor was proposed as a pretreatment prior to acid leaching. Alloying with zinc is expected to enhance dissolution of precious metals and reduce the amount of toxic chemical agents required for the leaching. This study examined the effect of the alloying pretreatment using model catalysts. Catalysts were immersed in leaching solutions for a predefined time with or without zinc vapor pretreatment, and the amount of dissolved metals was then evaluated. INTRODUCTIONAutomotive catalysts account for large portions of the world consumption of platinum (Pt), palladium (Pd), and rhodium (Rh) (Butler, J., 2011). Because of their limited production and high prices, recovery of the precious metals from spent catalysts is obviously an important issue. A representative structure of an automotive catalytic converter can be described as a monolithic ceramic support with a honeycomb structure which is coated with porous oxides such as those of aluminum (Al2O3), cerium (CeO2), and zirconium (ZrO2) (Heck & Farrauto, 2001; Matsumoto & Shinjoh, 2007). Small particles of precious metals, originally several nanometers or less, adhere to the oxides.Typical recovery processes for precious metals from scraps are shown in Figure 1 (a)-(c) (Habashi, 1997; Yoo, 1998; Shibata & Okuda, 2002). Precious metals can be recovered by using non-ferrous smelters as Figure 1 (a) shows. Smelted along with metals such as copper (Cu), precious metals and ceramics in the scraps are absorbed into the metal phase and slag phase, respectively. Because the metals separate from Cu as anode slime in successive electro-refining, such a process can recover precious metals as co-products of Cu. However, in order to prevent negative effects on the principal process, a specialized procedure is needed. Figure 1 (b) is a specialized approach in which scraps are melted at elevated temperature with Cu called the Rose process. Here Cu works as a collector metal, and the absorbed precious metals are then concentrated by oxidation of Cu. Such a process can separate precious metals from ceramics constituting catalyst converters. Smelting at high temperature, however, requires extensive equipment as well as a high amount of energy. On the other hand, hydrometallurgical processes may be effective to separate precious metals from ceramics into an aqueous solution, because chemical agents can act on these metals selectively (Figure 1 (c)). Leaching of precious metals, however, requires strong acid and oxidizing agents because of their corrosion resistance; this makes liquid waste disposal and the large environmental load controversial. To solve the problem, a metal vapor pretreatment was proposed (Okabe, Yamamoto, Kayanuma, & Maeda, 2003a, 2003b; Kayanuma, Okabe, Mitsuda, & Maeda., 2004; Kayanuma, Okabe, & Maeda, 2004; Itoh, Kayanuma, Miyake, Kimura, & Maeda, 2005). A flow diagram of the process using zinc (Zn) vapor is shown by Fig. 1(d). Exposed to Zn vapor, precious metals are expected to form alloys which dissolve more easily than pure precious metals, thus reducing the use of chemical agents and environmental load involved with successive leaching. In previous research (Sasaki, Miyaki, & Maeda, 2010; Sasaki & Maeda, 2010, 2012), dissolutions of precious metal alloys formed by Zn vapor treatment were examined in hydrochloric acid (HCl) using an electrochemical method, and it was confirmed that these metals dissolved at higher rates from the alloys than from their pure states (Figure 2). In this study, the availability of the alloying pretreatment was demonstrated by testing on model catalysts in leaching solutions."

Jan 1, 2012

By H. F. Zurbrigg

"The Frood-Stobie Mine is by far the largest metal producer in the Sudbury area. Its efficient development was made possible by the consolidation of three mining properties that covered parts of the same ore body. They were known as the Frood Mine, the Frood Extension, and the Stobie Mine.The southwest or Frood portion of the orebody was discovered by Thomas Frood and A. J. Cockburn in 1884. Cockburn's interest was acquired by J. H. Metcalf and W. B. McAllister and patents were issued to Frood, Metcalf, and McAllister in 1884. The property was purchased by the Canadian Copper Company (lnco) in 1886.James Stobie discovered the northeast or Stobie part of the orebody in 1885. In 1886 Stobie and Rinaldo McConnell applied for the location and patent was issued in 1886. They sold the property to the Canadian Copper Company (lnco) the same year.The Frood Extension property included very little of the ore zone at surface but it covered ore down the dip from Frood. Frank Cochrane was granted title to the property in 1908 and sold it to the Mond Nickel Company in 1910. The title was transferred to the International Nickel Company in 1929 at the time of the Inco-Mond merger.Prior to 1930 the three properties produced a total of about 1 ,000,000 tons of ore from mining done during the periods 1887-1903, 1913-1915 and 1925-1929. Since 1929 the Frood-Stobie operation has produced more than 120,000,000 tons of ore, about half from open pits and half from square set and blast hole stoping. The current production rate is in excess of 6,000,000 tons per year.The principal products from the ore are nickel and copper. The by-products are iron ore, cobalt, platinum, palladium, rhodium, ruthenium, iridium, gold, silver, selenium, tellurium, and sulphuric acid."

Jan 1, 1949

By K. N. Subramanian, H. Kanduth

"It is well known that chalcopyrite can be dissociated into simple sulphides by heating with elemental sulphur at about 475°C:CuFeS2 + S -> CuS + FeS2Experimental work was undertaken to determine whether this ""activation"" could be used to advantage in the selective leaching of copper from chalcopyrite concentrate.A method of treating copper concentrate with molten sulphur was developed and the activated product was leached in dilute sulphuric acid using oxygen, ferric iron or manganese dioxide as the oxidant. The object was to obtain a solution suitable for electrowinning with minimal purification, but it was impossible to obtain rapid extraction of copper without simultaneously dissolving a large proportion of iron. This was attributed to the fact that some of the copper was present as a low iron-copper sulphide (idaite) and that the pyrite formed during the ""activation"" step was more easily oxidized than natural pyrite."

Jan 1, 1973

By Yum Xiaoquan, Turgut Yalcin

"A laboratory study was carried out to determine the potential role and effect of ultrasonic irradiation in the flotation of a Sudbury copper-nickel sulphide ore. The use of ultrasound was tested separately at the pulp preconditioning, collector conditioning and flotation stages. While no significant benefits were evident in the latter two cases, ultrasonic preconditioning of pulp improved the grade-recovery performance and had the prospect of reducing reagent consumption rates. Tests were conducted on both the normal and oxidized ore samples, and several variables were investigated, including ultrasound frequency (25 kHz and 45 kHz), ultrasonic power (up to 1.6 W/cm2), duration of ultrasonic treatment (up to 60 minutes), and the intensity of pulp agitation employed during the application of ultrasound. Ultrasound frequency of 25 kHz and duration of 15 minutes yielded satisfactory results. Changes were found to occur in the temperature, pH and Eh of the pulp during ultrasonic processing. The favorable effects of ultrasound observed in this study were attributed primarily to its surface cleaning capability.INTRODUCTIONThe use of ultrasound for the surface cleaning of objects is well known. Ore flotation is based essentially on the surface properties of minerals, and hence stands to benefit from ultrasonic treatment which may help restore mineral surface characteristics that might have been lost or modified through oxidation, etc. Expected outcomes of this method of treatment include improved flotation kinetics, higher recovery, better selectivity, and savings in reagent consumption, as has been demonstrated by various researchers (Aldrich and Feng 1999, Celik 1989, Ozkan 2002, Letmathe et al. 2002, Nicol et al. 1986)."

Jan 1, 2005

By Peter Hayes, Evgueni Jak, Taufiq Hidayat, Gary O’Connell, Denis Shishin, Jeff Chen, Francis Letarte

"Knowledge of slag properties is required for the optimisation of smelting operations. The phase equilibria and viscosities of the Al2O3-CaO-FeO-Fe2O3-MgO-MnO-NiO-Cr2O3-SiO2 slags at conditions of interest to Koniambo Ni-laterite smelting operations have been investigated. High-temperature re-equilibration phase equilibrium experiments of industrial slags followed by rapid quenching and direct measurement of phase compositions using electron probe X-ray microanalysis (EPMA) have been undertaken in the olivine and pyroxene primary phase fields at temperatures between 1475 and 1600°C and SiO2/MgO weight ratios between 1.57 and 2.09. Phase equilibria predictions were performed using FactSage thermodynamic software. A slag viscosity model available in the FactSage thermodynamic package has been used to calculate the viscosities of the liquid slags. The Einstein-Roscoe equation combined with the predicted phase equilibria data have been used to estimate the viscosities of the slag slurries (slag + solids). The information provided can be used to assist in the evaluation of the furnace performance, to assess further optimisation of slag composition and to explore possibilities of targeted feed changes.INTRODUCTION One of the key steps in the production of ferronickel from nickel laterite ore at Koniambo Nickel SAS involves reduction and smelting of pre-dried nickel-bearing saprolitic ore (high Mg and Si) in an electric furnace at temperatures up to 1650°C. The characterisation of the slag properties as functions of key operational parameters, such as, temperature and composition, including liquidus, the proportions of solids and viscosity, is essential for improving control and optimisation of the operations. The slag produced in the smelting process is a complex oxide system with the major chemical components including Al2O3, CaO, Cr2O3, “FeO”, MgO, “MnO”, “NiO” and SiO2. Characterisation of these multi-component systems using a solely experimental approach becomes increasingly complex as the number of components is increased."

Jan 1, 2017

By Paul Girard

"The copper property of Madeleine Mines Ltd. is in Lapotardiere and Boisbuisson townships, Gaspe North. The initial find was made in 1964, and subsequently a copper deposit of 5.3 million tons of ore was outlined. The property lies in Ordovician sedimentary and volcanic rocks near the major granite intrusive of the McGerrigle Range. The host-rock is a 300-foot-thick metamorphosed silty shale unit, close to the contact of the intrusive. The structure itself coµsists of a southerly-dipping monocline or the south limb of an anticline, on which a large dragfold has been imposed.Chalcopyrite, bornite and chalcocite are the principal sulphides present in the ore. Of particular interest is the zoning arrangement of these sulphides. The orebody is chimney-like in shape and appears to be a fracture-filling deposit that is genetically related to the granite intrusive and is confined within a highly fractured zone of very brittle rock. The deposit presents features uncommon to any of the other known copper deposits in the Gaspe Peninsula."

Jan 1, 1969

By R. C. Beard

"Heap leaching, currently being applied in the treatment of low-grade ores in the south western United States, is shown to have potential for use in north western Ontario. The history and operation of the process are described, and cost comparisons are given.IntroductionHeap leaching is a simple, low-cost method of recovering gold from low-grade ore. Although it is not currently being used in Canada on a production scale, it is being used extensively, and successfully, in the southwestern United States as well as elsewhere in the world. Especially suited for large deposits of very low -grade ore, it also appears to be practical for use on small, high-grade deposits because it avoids the high capital costs of mills. Eveleth (1980) and others suggest that the capital and operating costs required for heap leaching are approximately 20% and 40% respectively of conventional milling methods.Northwestern Ontario is noted for its large number of undeveloped, small, high-grade gold deposits. Although there are a number o f larger and higher-grade deposits in the area as well, it is the relatively small undeveloped deposits which would benefit most from heap leaching, if it could be demonstrated to be a viable extraction method.To assess the significance of these small deposits, the Ontario Ministry of Natural Resources recently commissioned a consultants' study of the gold reserves in certain parts of northwestern Ontario. This report, titled ""Feasibility of Small-Scale Gold Mining in Northwestern Ontario"", by J.N. Neilson and R.C.E. Bray (1981, OGS Open File Report 5332), documents 106 known gold deposits having sufficient information to calculate gold reserves. A total of over 7.8 million tons having a weighted average grade of 0.19 oz of gold per ton were compiled in the proven, probable and possible categories, with an additional 8.2 million tons in the speculative category. Many of these deposits could be mined by open-pit methods."

Jan 1, 1983

"There are a number of disciplines in the minerals industry for which concern has been expressed regarding the sustainability of human capital. The boom-bust cycles that occur in the industry, the trend in tertiary education towards consolidation or in some cases cessation of minerals related programs and the increasing frequency of fly-in fly-out operations can all contribute towards a decline in the number of professionals with basic skills in process mineralogy. This paper describes approaches taken by the authors to incorporate process mineralogy into three levels of education, namely undergraduate, recent graduate and experienced professionals. The primary objective in designing the learning activities is the development of authentic learning experiences that provide participants with relevant skills in process mineralogy. Selected examples of approaches used by other education groups globally to address this issue are also provided.INTRODUCTIONThe boom and bust cycle of the mining industry has trickle down effects in tertiary education in terms of the ability of universities to consistently provide high quality graduates with relevant skills. When the commodity price surged in 2002 skills shortages in critical resource related professions were reported and despite investment in skill development there was a view from employers that not enough young people were graduating from relevant education programs (PricewaterhouseCoopers, 2012). At the time this signalled positive growth for engineering disciplines catering to the mining industry, however during the downturn cycles, most recently since 2012, graduates exiting from the discipline can find employment difficult and this contributes to reduced enrolments in subsequent years. From an AusIMM (Australasian Institute of Mining and Metallurgy) members’ employment survey conducted in 2013, more than half of the graduates exiting from disciplines related to mining and minerals were not confident of finding employment (AusIMM, 2013). In the long term the concern is not only how to sustain enrolment and graduate numbers but also to provide the opportunity for students to acquire the professional skills that they require to make them attractive to industry.Maintaining and sustaining core competencies in the minerals discipline is an ongoing challenge. There have been a number of recent papers on this issue presented at international conferences (e.g. McCaffrey et al, 2014; Drinkwater and Napier-Munn, 2014) and there is general agreement that one of the ways in which the deficit in foundation concepts can be addressed is through workplace development. Drinkwater and Napier-Munn (2014) presented data from a survey of industry professionals that indicated that more than 90% of respondents undertook on average 30 days of training each year of which approximately 5 days was professional short courses."

Jan 1, 2016

By Rob Morrison, Peter Cameron

"Many products and technologies have been developed from outcomes of research projects carried out by the Julius Kruttschnitt Mineral Research Centre (JKMRC). When these products and technologies are applied to the design and optimisation of blasting, comminution and separation, improvements in profitability can be realised.In 1970 Alban Lynch promoted two practical ideas to improve plant operations:• Ore and equipment properties can be separated allowing experience with one type of ore or equipment to be transferred to other types of ore and equipment. If this experience was encapsulated in a mathematical model, then these properties could be combined and used to simulate (ie. to design and to optimise) complete mineral processing circuits.• Many problems associated with scale-up from laboratory to industrial equipment could be eliminated by experimental work on full-scale equipment in the plant.Many JKMRC research projects have focussed on the development of models of unit operations in mineral processing and their application to process simulation.Models of comminution and classification developed at the JKMRC have been used since the early 1980's. Ore characterisation techniques developed to support these models are licensed world wide through JKTech. The application of comminution modelling techniques to blasting, which optimises the process feed size distribution is used in Mine-to-Mill® projects. The advances in the understanding and modelling of froth flotation over recent years have provided the opportunity for integrated ore characterisation and process optimisation from resource to product.JKMRC project outcomes often provide proven opportunities for the mineral industry to improve performance and productivity. JKTech was established in 1986 to commercialise and market the most promising outcomes and thus ensure their continuing availability to the mineral industry.They include:• Commercial software (JKSimMet, JKSimBlast and JKMetAccount).• Monographs (Comminution and Blasting).• Technologies (Mine-to-Mill® and flotation optimisation).• Hardware products (JKFrothCam, JKJetLift® and the Mineral Liberation Analyser).This paper summarises these technologies and their benefits."

Jan 1, 2003

By D. Kalumba, S. Jjuuko

"Thin Spray-on Liners resist relative small deformations (< 1 mm) between rock blocks or fragments in terms of a combination of shear, adhesive and tensile-bond strengths. Shear-bond strength addresses the ability of a thin liner to resist stresses that act parallel to the rock-liner interface. Therefore quantification of shear-bond strength is essential in the formulation of design standards and requirements for Thin Spray-on Liners. In this paper Thin Spray-on Liner support mechanisms are reviewed. In addition previous methods of Thin Spray-on Liner shear-bond testing are discussed. The paper also explains the research being carried out at the University of Cape Town to investigate the effect of different parameters on the shear-bond strength.INTRODUCTIONRock surface support is widely used to combat rockfalls and resulting injuries and fatalities in the vicinity of active faces (Potvin, 2002), where workers spend most of their time (Adams & Baker, 2002; Potvin, 2002; Lacerda, 2004). The conventional (traditional) surface support systems in underground rock support include passive methods such as mesh and lacing and active methods such as shotcrete. However, rockfall sources between 1990 and 2000 in Nevada gold mines showed a steady increase in rockfall injury associated with mesh support as shown in Figure 1 (Lacerda, 2004). The conventional methods also negatively impact the mining operations with regards to costs, logistics and mining cycle times due to large material volumes (Tannant, 2001; Ozturk & Tannant, 2010; Ferreira, 2012). Therefore, these systems need to be substituted, with enhanced methods, in order to realize the business target of the mining industry of providing the planned return on investment made without harm and within budget."

Jan 1, 2015

By James Pirie

"The major Archean gold deposits in the Red Lake greenstone belt, which have produced over 374 million grams of gold since 1930, occur near the top of the lower komatiitic to tholeiitic mafic to ultramafic metavolcanic sequence. The upper calc-alkalic mafic to felsic rocks form three discrete and separate ediftces overlymg this lower sequence.The gold deposits are classified according to their stratigraphic or lithologic associations into:1) mafic-volcanic-hosted deposits;2) felsic-intrusive-hosted deposits; and3) stratabound deposits.Group 1 and to a lesser extent Group 2 deposits occur within zones of alteration several square kilometres in extent. The nature of this pervasive alteration can be characterized by comparison of petrochemical data from the altered rocks and their fresher equivalents some distance away. The altered rocks have substantial addition of SiO2> CO2, K2O, As and Sb and subtraction of Na20, CaO, MgO and total Fe. Cr, Ni, Co and Zr appear to have been relatively immobile. Hydrothermal alteration and gold deposition probably accompanied early fumarolic activity and continued during subsequent deformation the metavolcanic sequence, with gold eventually being mobtltzed and concentrated into major vein structures to form the present orebodies. The smaller Group 2 deposits formed by emplacement of felsic intrusions into already altered, anomalously gold-bearing mafic metavolcanics, with the heat from the intrusions setting up parasitic hydrothermal systems which mobilized the gold and deposited it along with minor sulphides in fractures in the cooling intrusions."

Jan 1, 1982

By Ralph J. Holmes, David McCallum, Alan Roberts, Rolando Orense, University of Auckland, Tobias Krull, Tom Honeyands, Kenneth Williams

"The safe ocean transport of bulk commodities like iron ore, coal, nickel ore, manganese ore and bauxite by large bulk ships is vitally dependent on the stability of the cargo under the influence of wave induced ship motion. Safety standards are set by such bodies as the International Maritime Organisation (IMO) with recommended tests for the assessment of bulk commodities. Since the 1960s, the bulk cargo code (BC Code) commenced defining methods to determine the Transportable Moisture Limit (TML) for transportation of bulk commodities. By the latter part of the 1960s, three TML test methods were defined, namely the Flow Table, Proctor-Fagerberg and Penetration tests. All three tests were predominantly aimed at determining TML values for mineral concentrates.More recently, bulk commodity producers, Maritime Organisations and Port Authorities worldwide have been investigating whether commodity based TML methods better reflect realistic safe ship transportation than the current concentrate based TML test methods. In these investigations, the relationship between the mineralogical and particulate parameters of specific commodities with respect to cargo stability and moisture retention has provided insights into the development of tailored TML test methods. To this end, an AMIRA International project (P1097) undertaken by CSIRO, TUNRA Bulk Solids, the University of Newcastle and the University of Auckland assisted the IMO Technical Working group to investigate the relationship between iron ore fines characteristics and a new TML test specific for iron ore fines bulk cargoes.A review of the three standard concentrate based TML methods and characterisation studies of iron ore fines, as well as cyclic triaxial testing to determine liquefaction resistance, resulted in the development of a modified Proctor-Fagerberg method for determining the TML of iron ore fines. Of particular importance in determining TML is mineral composition, porosity, particle density and allowing time for moisture equilibration."

Jan 1, 2016

By W. A. Green

Introduction While pilot-mill operations were being carried on at Flin Flon, as described by R. E. Phelan (1), a detailed topographic map was being made of the area in the vicinity of the ore-body for later use in laying out plans for the final plant. The area covered by this survey was 6,600 feet by 6,600 feet, with contours on 2-foot intervals. As mentioned by Mr. Phelan, it was definitely decided at the end of November, 1927, to take up the option on the Flin Flon property and to proceed immediately with the plans for construction of a metallurgical plant at Flin Flon to treat 3,000 tons of ore per day, and of a hydro-electric power plant at Island Falls, Saskatchewan, to supply power for the future operations at Flin Flon. Railway Built From The Pas to Flin Flon Just as soon as the decision was made to go ahead with the construction work and opening-up of the property, it was of course essential to give immediate attention to the building of a railway to the mine. Many years previously, a preliminary survey had been made for a railway to branch off the Hudson Bay railway at a point 4.7 miles northeast of The Pas, and, during certain negotiations in 1925, the Provincial Government of Manitoba had agreed to guarantee the railway bonds necessary to finance the building of the line, so that it was possible to organize for this work immediately. A contract was let by the newly organized Manitoba Northern Railway Company to the Dominion Construction Company, Ltd., and Tomlinson, for the building of the railway to the mine, a distance of approximately 87 miles (see Figure 1). The Manitoba Northern railway is a subsidiary to the Canadian National railway, and all engineering and supervision of the contractors was done by the Canadian National engineers. Actual construction work was started in January, 1928. The first 52 miles of the railway from The Pas to Cranberry Portage is over fairly level, although slightly rolling, country, and a considerable portion of the route is over muskeg area. Rails were laid on top of the frozen muskegs. Gravel deposits were opened-up along the line and, before warm weather; sufficient ballast .was distributed in the muskeg areas to prevent thawing under the track, and thus give the necessary support to allow uninterrupted transportation over the line.

Jan 1, 1935

By D. Settles, R. Rose, P. L. Dunn

"A new mineral sands operation is being developed in Georgia by Southern Ionics, Inc. (SII). Prevailing mineralogy and certain design constraints required detailed testing and circuit analysis to create a robust separation processes. The floating wet concentrator plant (WCP) and mineral separation plant (MSP) flow sheets were designed based on historical testing information and recent SII test campaigns on various composite feed samples. The flow sheets were finalized through rigorous process and orebody sequence modeling.The process uses traditional physical separation equipment; however a new MT spiral, the MG12, was selected for use on board the WCP for roughing duty. The MG12 spiral is a two-stage, twelve-turn spiral that has been proven to achieve very high recoveries of heavy minerals. The floating plant includes feed desliming operations, a central MT surge bin for optimum spiral circuit feed control and ancillary operations for concentrate and tailings handling. Scrubbed heavy mineral concentrate (HMC) is then transported to the MSP for concentration of the titanium and zirconium bearing mineral fractions.The testing, flowsheet development, and plant design will be described and explained, and a brief summary of the current project status will be given.IntroductionSouthern Ionics Inc. (SII) is a privately held chemical manufacturing company, founded in 1980 by Milton Sundbeck. SII focuses primarily on the sale of specialty and intermediate inorganic chemicals. Core markets include cement and refinery catalysts, molecular sieves, zeolites, pulp and paper, pharmaceuticals, TiO2 and water treatment. SII is built on the four cornerstones of service, quality, technology and delivery with all SII facilities ISO certified and key products used in potable water treatment certified to NSF standards. SII owns and operates its own transportation fleet and is focused on being a low cost producer, committed to safety and the environment."

Jan 1, 2015

By L. K. Walker, G. A. Kosick, P. D. Young

"MillEX is an information management system designed by mineral processors for mineral processors. The system utilizes ""cutting edge"" software technology to gather and store all automatically and manually recorded data from the plant operation and laboratories. This data is delivered to the desk of superintendents, metallurgists, technicians and managers, and permits the user to query, correlate, graph, report and present this data in minutes. In the past this task would have taken days and even weeks of tedious work to complete.MillEX allows the engineer/analyst to quickly develop a very thorough understanding of the complex relationships of process variables and equipment that exist in the plant, and their effect on product quality and quantity. The time and resources that are currently wasted on duplicating data entry will be an effort of the past.This paper describes the structure of MillEX and how it conforms to the needs of mineral processing personnel.INTRODUCTIONPicture a personal computer on your desk which will carry out the following commands:1. Plot a graph over the last six months, using weekly averages, of percent minus 200 mesh material in the primary cyclone overflow.2. Overlay this graph with a graph of concentrate grade versus recovery over the same time period.3. Retrieve a prior month end report, update all operating supplies tables and metallurgical performance with this months data, and embed the graphs created above.4. Edit text and print the current month end report. This is only one example of the type of power MillEX isbringing to the mineral processing industry."

Jan 1, 1992

By Peter Wells, Adrian Sabau, Turgut Yalcin

"The nickel ores of Sudbury contain substantial amounts of the gangue mineral pyrrhotite (Fe7S&) which causes certain diflculties in the milling of these ores. This paper proposes a process called “magnetoflotation” as an effective means of dealing with pyrrhotite. The method reduces the pyrrhotite content of concentrates by applying a magneticjield on the path product as it leaves the flotation cell.Successful performance of magnetoflotation requires the optimization of several variables. In this study, three of the variables (air flowrate, collector concentration, pother concentration) were investigated by Box- Wilson experimental design, and others (magnet speed, grind size, pulp density, flotation time) were examined individually. The process was tested on a Falconbridge nickel ore, assaying 1.92% Ni, and under the best operating conditions, a concentrate was obtained with 13.56% Ni grade and 74.32% recovery in a single step. Further improvements to grade and recovery were possible by cleaning and scavenging. The same ore was also tested with conventional methods for comparison, and results indicated that magnetoflotation performed better.INTRODUCTION“Magnetoflotation” refers to the process of carrying out magnetic separation and flotation simultaneously within the same device, and is intended to prevent magnetic minerals from reporting to the froth products while non-magnetic minerals are being floated. Typical cases where this method might be beneficial include the processing of magnetite and nickel ores. Its use on magnetite ores has been reported elsewhere [Yalcin, 1992; Yalcin, 19931. This paper describes its application to nickel ores, more specifically to the nickel ore of Falconbridge Limited in Sudbury."

Jan 1, 1999

By E. W. O'Brien

Personnel protection involves effective grounding and positive clearance of faults. This paper deals, in a general sense, with various schemes to achieve fool-proof personnel protection and reduce, to a minimum, the effects of human error and equipment failure.

Jan 1, 1966

By Yongqiang Liu

Background For refractory gold ores with high carbonate contents ! Acid pressure oxidation ! High acid consumption (if low sulfur content) ! Low oxidation efficiency due to CO2 in autoclave ! Problems with slimy precipitates (gypsum, etc.) ! Alkaline pressure oxidation ! Difficulty in fixing arsenic ! Low gold dissolution due to iron hydroxides/oxides coating ! High reagent costs Summary ! Carbonate and sulfide minerals had similar floatability across the pH range tested (5 - 12) using sodium oleate as a collector; ! Thioglycollic acid or citric acid depressed the flotation of pyrite but could not depress chalcopyrite when used alone; ! Combination of thioglycollic acid and citric acid had a much stronger depressive effect, and the mixture depressed chalcopyrite as well as pyrite between pH 8 and 11 without affecting the flotation of calcite and dolomite; ! Calcite could be separated from chalcopyrite and pyrite; dolomite could be separated from pyrite but not from chalcopyrite under the tested conditions.

Apr 1, 2005