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By Scott Rosenthal

?EMESRT History ?Design Philosophies (DP?s) ?Industry Successes ?Participation Thinking Differently Earth Moving Equipment Safety Round Table ? Use a critical mass to influence Marketing ? Define ?Problems?not ?Solutions? ? Leave the OEM designers to develop solutions Work within the companies to improve purchasing

May 1, 2010

By Matt Schuett

Antamina Mine Facts • Surface Water Design Principles • Drainage Areas • SEDCAD Modeling • Impacted Runoff Collection • Clean Runoff Collection • System Flexibility • Outfall Construction

May 1, 2004

By W. N. Roman

This paper will examine the challenges involved in ventilating and cooling South African mines, with particular emphasis on solutions to the issues of heat (generally associated with depth), mechanization and energy efficiency. Comparisons will be made with other international mining areas. Some of the deepest mines in the world are to be found in the South African goldfields. The Mponeng mine is approaching 4,000 m below surface, with virgin rock temperatures (VRT) of between 60°C and 70°C. Mining at these depths has only been possible with the use of large refrigeration plants supplying cold air, water and ice to the workings. In the Bushveld Igneous Complex, where most of South Africa?s platinum mines are located, similar VRTs are being experienced at significantly shallower depths. This is due to the different geothermal properties of the host rock between the two areas. Existing mines are being forced to go deeper and new underground mines are being planned and constructed in other areas with widely differing thermal conditions. South African metal mining has traditionally been labour intensive for historical reasons as well as for the narrow tabular nature of many ore bodies. Due to cost pressures and labour problems, some mines have been investigating the possibility of using mechanized equipment, both diesel and electric, to increase production and to improve efficiency. Studies have been carried out to determine the effect of the additional equipment on the overall ventilation system and some of the conclusions are discussed. The use of diesel equipment adds heat and pollutants to the ventilation air but, although electrical equipment has a lesser effect on the ventilation systems, it is generally less favoured due to claims of lower flexibility/manoeuvrability. Mechanization holds the promise of more concentrated mining activities but, with higher localized ventilation and cooling needs. Systems which will control the provision of air and cooling more effectively are required and are being implemented. In the 1990s and early 2000s, the South African economy experienced significant growth which was not matched by the growth in infrastructure. Consequently, at present there is a shortage of electricity generation capacity which affects large industrial consumers, including mines. Increasing levels of heat and mechanization will require more electrical energy for ventilation and cooling. There are many initiatives underway to save power or to shift consumption to periods of national low demand and these will be described.

Aug 1, 2013

By M. Lahtinen, B. Saxén, M. Latva-Kokko

The conventional jarosite precipitation process with neutralization by zinc calcine is widely utilized in the zinc industry. However, it has a significant drawback of causing losses of valuable metals like zinc, lead and silver to the jarosite. This comes mainly from the content of these metals in the calcine used for neutralization. As the zinc plants today want to maximize metal recoveries and minimize the amount of residues, this matter has become more and more relevant for zinc producers. Outotec developed and patented in early 2000 an improved version of the jarosite precipitation process in which the need for neutralization can be minimized, thus the metal losses to the jarosite also can be minimized. At the same time, the iron content of the jarosite increases and the amount of produced jarosite is smaller. The main feature of this process is to start the precipitation from ferrous iron after having reduced all the iron by zinc concentrate in a separate step before jarosite precipitation. Iron is then oxidised back to the ferric form simultaneously with jarosite precipitation. By this method, the formation of sulphuric acid is only half that compared to the conventional method and the need for calcine for neutralization can be avoided. High mixing and oxygen dispersion capability are needed in this jarosite precipitation process. Such capabilities are found in the Outotec OKTOP® reactor series. High performance reactors are not only needed to generate high quality precipitates, but also to maximize oxygen utilization; i.e., to minimize operation costs. Outotec’s latest development in this area is the OKTOP® plant product in which not only the reactors, but also all the accessories are designed, manufactured and delivered by Outotec. One responsible supplier ensures efficient and fast delivery and can provide mechanical and performance guarantees for the entire plant unit.

Jan 1, 2016

By J. Cayouette, C. Bolduc, P. Blatter

"The LaRonde mill was commissioned in 1988 and began treating ore from the Penna shaft in 2000. The mill has been expanded to accommodate 7,500 t/day, but ramped down to 6,000 t/day since the deep extension began. The process recovers gold, silver, and base metals. In 2008, the Goldex plant began trucking gold-pyrite concentrate to a treatment plant feeding pulp to the LaRonde mill, increasing gold output by 40,000 oz. In 2009, the high-grade Lapa ore processing facilities were annexed to the LaRonde plant, increasing gold output by 120,000 oz. This paper outlines the metallurgical considerations related to the treatment of different ore types.RÉSUMÉ Le concentrateur de la mine LaRonde a été mis en service en 1988 et a commencé à traiter le minerai du puits Penna en 2000. La capacité du concentrateur a augmenté afin de permettre le traitement de 7 500 tonnes de minerai par jour, capacité qui est retombée à 6 000 tonnes par jour (tpj) depuis le début de l’extension en profondeur de la mine. Ce procédé permet de récupérer de l’or, de l’argent et des métaux communs. En 2008, l’usine de traitement Goldex a commencé à transporter par camion du concentré de pyrite et d’or vers une usine de traitement alimentant en pulpe le concentrateur de LaRonde, augmentant ainsi la production d’or de 40 000 onces. En 2009, les installations de traitement du minerai à haute teneur de Lapa ont été annexées à l’usine de traitement de LaRonde, augmentant la production d’or de 120 000 onces. Cet article passe en revue les considérations métallurgiques liées au traitement de différents types de minerai."

Jan 1, 2017

By J. J. Fitzpatrick

"This paper deals with the methods used by Quebec Cartier Mining Company in the evaluation and selection of new haulage equipment and in increasing the productivity of the existing fleet.Selection of new equipment is based upon the comparison, for each model under consideration, of the capital investment required and the estimated operating costs and production rate. The calculation of the production rate is based on a widely used estimating procedure. Actual operating conditions considered in the method include: payload, haul distance, road grade, rolling resistance, loading and dumping times, and operational efficiency. A digital computer is used to handle the large volume of repetitive calculations required. Where a fleet of haulage equipment includes trucks of different size and performance characteristics, the problem exists of assigning each truck type to the different working locations to minimize total cost. Linear programming can be used in the solution of this problem."

Jan 1, 1967

By M. Maley, S. Burling, R. Ring

ABSTRACT The numerous global uranium deposits vary significantly in mineralogy, grade, and textural characteristics; therefore, information from traditional (or conventional) sources on the fundamentals of leaching uranium and gangue minerals is not always applicable when studying particular ores. Empirical studies can be effective in understanding leach systems and can lead to improvements in process design but there remains a lack of fundamental understanding necessary for ongoing process optimization as ore bodies continue to vary. ANSTO Minerals has undertaken a work program to address several fundamental questions about uranium leaching, including the unexpected impact for some ore types of leaching at high oxidation potential.

Jan 1, 2012

By R. B. McIntosh, S Ramanchuk

A brief description is given of the process used by Sherritt Gordon Mines Limited to recover cobalt metal from nickel-cobalt sulphides. A description of the equipment with the operating conditions is presented with an evaluation of the corrosion test results for various stainless steels and other acid resistant materials for the part of the process involving the sulphuric acid leaching of nickel-cobalt sulphide slurry under air pressure. SINCE 1954 the Sherritt Gordon ammonia leach process has been used at Fort Saskatchewan to recover nickel metal, copper sulphides and cobalt-nickel sulphides from nickel concentrate produced at Lynn Lake, Manitoba. 'To develop a process for recovering cobalt and nickel from the cobalt-nickel sulphides, studies were carried out in the Sherritt Gordon laboratory and pilot plant and, late in 1957, continuous acid leaching of sulphides was started in the refinery. In September 1958 the present equipment

Jan 1, 1961

By Samuel O. Akande

"Gold occurs as native metal, in electrum, and in a telluride mineral in quartz carbonate veinlets of three vein systems at the Ross Mine, northern Ontario. The 14 Vein System is made up predominantly of concordant veinlets within layered ankeritic dolomite stratabound by, and conformable with, andesite tuff Individual veinlets contain pyrite, sphalerite, galena, chalcopyrite, tennantite, pearceite, proustite, native gold and electrum in a matrix of quartz, dolomite, ankerite and calcite. The 2B Vein System is made up of both concordant and discordant veinlets within andesite tuffs. The veinlets contain pyrite, chalcopyrite, sphalerite, bornite, tennantite and free gold in quartz, calcite and dolomite. The 18 Vein System is comprised of stockwork veinlets in and around intrusive syenite which has both sharp and gradational contacts with enclosing andesite tuff The veinlets contain pyrite, chalcopyrite, bornite, chalcocite, native gold and calaverite. Sulphide and silicate minerals in veinlets and wall rocks are stable assemblages for the regional metamorphism of greenschist rank. ,The 14 Vein System is interpreted as a metalliferous siliceous carbonate chemical sediment, the components of which were leached from the underlying volcanic rocks by convecting sea water and subsequently deposited on the sea floor between the extrusion of flows and pyroclastic rocks. Subsequent regional metamorphism and intrusions remobilized and redistributed the syngenetic stratabound material into dilatant fractures in adjacent tuff, as in the 2B and the 18 vein systems."

Jan 1, 1982

By L. Tejeda, J. R. Donald, R. Parra, J. Duran, P. H. Lauzon

"Crucible slag tests were employed to evaluate different refractory brick classes for the Cerro Matoso electric furnace. Comprehensive analysis was conducted to evaluate the crucible erosion and characterize any slag/refractory reaction products.The classes of refractories investigated were:•,tar-impregnated magnesia;•,rebonded fused grain magnesia-chrome;•,direct bonded magnesia-chrome;•,alumina-chrome;•,picrochromite; and•,magnesia-alumina (spinel).It was concluded that tar-impregnated MgO bricks were the most suitable for the slag chemistry and furnace environment according to corrosion and infiltration resistance. A picrochromite (MgCr2O4) brick performed exceptionally well with regards to erosion resistance, however, the slag infiltrated extensively through the brick pores. Alumina-chrome, direct bonded magnesia-chromite, and spinel (magnesia-alumina) bricks were evaluated as not suitable for use in the furnace."

Jan 1, 1999

By E. Lehtila, J. J. Talja, R. Jahila

Kopar Oy is acknowledged for engineering and manufacturing of robust systems for bulk material handling, especially at power plants and non-ferrous smelters. We have over thirty years of experience with systems specifically designed for hot and abrasive conditions, aiming at low cost of ownership, low operational expenses and high availability. Although Kopar has numerous applications in mechanical conveying, there is an increasing number of pneumatic conveying applications at copper smelters. They relate to conveying of concentrate, and primary and secondary flue dusts. Challenges of pneumatic conveying for concentrate are mechanical and do relate to broad particle size distribution and high abrasivity of the concentrate and the silica. Therefore, special attention shall be paid to system design and ceramically lined bends in the pipeline. Challenges of pneumatic conveying of primary flue dust relate predominantly to material stickiness and poor flowability which are mainly due to fine particle size and formation of sulphates and furthermore, crystalline water. Additional challenges of secondary dust, the white converter dust, are primarily due to the extremely fine 0.1–1.5 µm particle size and problems which come with this. Effect of material characteristics like size distribution, morphology and chemical composition in pneumatic conveying are discussed in detail. INTRODUCTION Fine materials like concentrate, feed mix, flue dusts (from waste heat boiler and electrostatic precipitator) and secondary dusts need to be conveyed at smelters. Both horizontal and vertical conveying and combination of those are used. For the purpose, both mechanical and pneumatic conveying are applied. Most widely used equipment are drag chain conveyors and various combination of pneumatic systems, e.g. air lift, dense-phase and dilute phase pneumatic conveyors. Kopar has 30 years’ experience with multiple material handling systems. Furthermore, acquired companies like Elmomet Oy and SITE Oy (both currently fully merged and integrated into Kopar Oy) have even longer history, especially in pneumatic conveying. It is commonly known that the finer the dust the more difficult it is to be conveyed pneumatically. Sulfates with crystal water makes it all even more difficult, if not ineligible. Challenges related to pneumatic conveying of various fine materials is discussed in detail in the paper.

Jan 1, 2019

By lchimura. R. .

Japan Oil, Gas and Metals National Corporation (JOGMEC) and Centro de Investigation Minera y Metalurgica (CIMM) commenced a five year project from 2001 to modify the treatment of the furnace dust from Teniente converter containing harmful elements like arsenic and lead. The project was supported by Japanese and Chilean governments, and a demonstration plant was installed and operated at Las Ventanas Smelter and Refinery (Division Ventanas CODELCO). The basic and detailed engineering was made by Mitsui Mining and Smelting Co., Ltd (MMS) based on the joint study among JOGMEC, CIMM and Division Ventanas CODELCO. Arsenic in flue dust is lixiviated by sulfuric acid and fixed as crystalline ferric arsenate, where leachability of arsenic will be lower enough than the regulation, 5mg/I by TCLP (Toxicity Charactaristic Leaching Procedure) of USEPA. On the other hand, the recovered copper from the dust will be fed to the copper production process at Las Ventanas Smelter and Refinery, while zinc will be recovered as the exportable product. As introducing the crystallization and growing stage, the stable crystalline ferric arsenate formation can be achieved under the normal pressure.

Jan 1, 2007

By L. T. Pasiechnyk

After a brief review of the various hydrocarbon storage methods currently being utilized and statistics on underground hydrocarbon storage, this paper will briefly describe the technology involved in solution mining salt to create caverns of engineered shape and size and briefly discuss the economical and environmental advantages of hydrocarbon storage in solution-mined salt caverns. Other possible uses of salt caverns will be mentioned.

Jan 1, 1978

By Shuan-cheng Gu

Roof bed separation often occurred due to the deformation incoordination of surrounding rock following the excavation of mine roadway. Bed separation has effect on the bolts, and the estimation of the influence will directly affect the safety of support systems. In this paper, the hyperbolic function model to analyze the load transfer mechanism on the bolts was simplified as the exponential function form for easy calculation. An elastic-plastic analysis model of the bolt loading occurred by the bed separation was established. And the development low that the bed separation affected to the bolt loading was discussed. According to the parameters analysis of different separation values and locations, the influence law of the bolt loading caused by roof bed separation was summarized. Finally, the effects of bed separation were considered for the bolting design, it was able to provide a reference to the anchorage design of stratified rock.

Aug 1, 2013

CSIRO Minerals, in association with the AJ Parker CRC for Hydrometallurgy, has an active program of hydrometallurgical research in which physical and computational modelling are used to better understand and improve a range of different unit operations. The modelling is based on flow simulation (Computational Fluid Dynamics or CFD), but incorporates other physical and chemical phenomena of importance, such as droplet break-up and coalescence, species transport and reaction. This paper reviews some of the major projects that have been undertaken at CSIRO Minerals and will illustrate the critical importance of hydrodynamics to the performance of unit operations and the improvements that can be made to performance using such modelling techniques. Unit operations that are discussed include solvent-extraction, gravity thickeners, flotation cells, bio-heap leaching and stirred tanks.

Jan 1, 2005

By M. El Tokhi, H. Arman, B. M. Amin

"This paper aims to overview some mechanical and physical features of the gabbroic rocks. The study has two phases: filed study/in-situ measurements and laboratory work. During the field studies, rock block samples were collected from different locations of the study area to represent the different types of the gabbroic rocks. Either core or rock samples for various tests were prepared from rock samples taken to the laboratory. The unconfined compressive strength (UCS), indirect tensile strength (ITS), point load index (PLI), Schmidth hammer rebound value (SHV), slake durability index (SDI), sonic velocity (SV) and unit weight (UW) test were carried out either on the selected rock block samples or core samples.INTRODUCTIONThe geology of the United Arab Emirates (UAE) has been divided into three major rock units (Lippard et al., 1986); an autochthonous succession, allochthonous units composed mainly of Mesozoic rocks and include the Sumeini Group (concomittent slope sediments), Hawasina Complex (basinal sediments) and the Semail ophiolite nappe (massive slice of former oceanic crust), that were emplaced as a series of thrust nappe in the Late Cretaceous and Neo-autochthonous sequence of Maastrichtian and Lower Tertiary sediments.The Semail Ophiolite (600 km long and up to 150 km wide) is thought by some authors (Glennie et al., 1990) to have been generated along a subduction related back-arc spreading axis during the Cenomanian-Turonian and was obducted onto the Arabian continental margin during the Campanian. Others, however, consider it to represent a primitive arc-spreading center related to oblique subduction Lippard et al., 1986). The Ophiolitic rocks in the study area comprise mantle and crustal sequences. The mantle peridotite and crustal gabbros are the dominant rock types of the exposed Semail Ophiolite north of the Hatta zone. This paper is only concentrated on the gabbroic rocks."

Jan 1, 2015

By A. Pawelczyk, D. Hreniak, E. Zych, W. Strek, K. Grabas, A. Ostrowski

"Mongolia is a country rich in rare earth resources. In the experiments carried out samples of the Mongolian ore were processed to obtain a lanthanide concentrate. The concentrate underwent hydrometallurgical processing. At the same time radioactive elements were removed. The lanthanides were obtained in the form of hydroxides that were further processed in order to get concentrated products. As a result cerium, lanthanum and neodymium-praseodymium concentrates were separated in the process. Also a concentrate of remaining elements: samarium, europium, gadolinium, terbium, dysprosium, holmium and erbium was obtained. INTRODUCTIONAccording to the assessment of the US Geological Survey, Mongolia possesses 16.77 % of the world total rare earth (RE) resources (Daly, 2011); that is the second largest RE reserve in the world, estimated to be 31 million tonnes in terms of rare earth oxides (REO). In the face of Chinese RE trade restrictions, Mongolia emerged as an important economical partner in mining and exploitation of these critical raw materials. This country is recognized as having more than five large RE deposits in the southern provinces. The most important are Lugeengol (Lugin Gol), Mushgia Khudag, Khotgor and Khalzan Buregtei (Eurasia, 2010). The Mongolian government has taken measures to facilitate western investments, nevertheless the country is economically dependent on China, the basic trading partner, particularly where exports are concerned.In the late 1970s Hydromet Kowary Enterprise, Poland, took up, along with the Wroclaw University of Technology, research and technological study on lanthanides recovery from raw materials of Vietnamese and Mongolian origin and from Indian monazite sands (Kowalczyk, 1990; Kowalczyk & Mazanek, 1987; 1990). For that purpose, a rare earth processing plant had been constructed with the capacity of about 10 t/year of hydroxide concentrate. The facility included several technological operations like grinding, flotation, hydroxide concentrate production in the hydrometallurgical processing, particular RE separation, and production of commercial products in form of CeO2, La2O3, Nd2O3, Pr2O3, and misch metal. Additionally work had been carried out in Kowary on the manufacture of yttrium and europium oxides of high purity, which were intended for color TV picture tube production in Poland."

Jan 1, 2012

By E. You

The concentrator at Kennecott Utah Copper currently has 4 lines with a configuration of one SAG mill feeding two ball mills. The slurry that reports to each ball mill will vary resulting in an unequal load of material. This configuration contains two separate sumps that receive material from a distribution box relying solely on natural slurry flow to feed each sump. The unequal split to each mill results in one mill receiving a greater amount of material. This will result in the equipment on one mill reaching limitations that may affect product quality and the operation of the equipment near maximum. The parallel mill in this condition will often have additional capacity that can be used but cannot be utilized due to the unequal split. The major consequences of this issue result in reduced throughputs and metal recovery. To resolve this condition an advanced control strategy was implemented to control the split in April of 2002 using equipment that was in place.

Jan 1, 2007

By J. G. Whellock, J. W. Matousek

"In spite of their importance to the economics of many metallurgical projects, the values and technical aspects of precious metals losses in smelting operations are relatively undeveloped subjects. This paper attempts to provide a condensed overview of precious metals losses in pyrometallurgy, using some of the limited production and experimental data available. It is intended for three general groups of metallurgists - operators attempting to improve recoveries, cost-accounting engineers making estimates of metal losses in new or modified smelting plants, and research engineers and students.Distribution coefficients of precious metals, the ratios of metal or matte assays to slag assays, are convenient means of comparing smelting processes and the tendencies of the different metals to enter the slag. For silver in lead blast furnaces this ratio is approximately 250;for gold and the platinum group metals in submerged-arc, electric furnaces it is 900. The ratio for gold and PGMs in converters varies with the degree of oxidation of the charge. The over-all cycle-average for industrial installations is tentatively estimated to be 35.IntroductionThe magnitude of precious metal s losses in pyrometallurgical operation s is difficult to assess. The primary producers are generally reluctant to discuss the subject. The by-product producers (the large sulphide smelters o f copper , nickel, and lead) might be more willing to disclose information, but these have precious metals in their feeds in such dilute quantities that accurate accounting is extremely difficult. It is not until numerous processing steps have been taken t hat the precious metals become sufficiently concentrated to permit acceptably accurate sampling and analytical procedures to be followed. Thus, knowledge of the precious metals contents o f the intermediate mattes and slags may simply be unavailable."

Jan 1, 1990

By Hans Lundberg

An electric survey from a 'plane flown over the ground is much faster and cheaper than an electric survey carried out on the ground. The results are obtained as continuous recordings that are resolvable into both a depth expression and a conductivity effect, so that the indications are easier to evaluate, as well as to correlate from one flown line to the other. The prospecting technique adopted in our electric airborne surveys may be brie fly described as follows: A loop of many turns of insulated copper cable is fastened around the fuselage of the 'plane and connected to a generator supplying a few ampere alternating current, usually of a frequency less than 1,000 cycles per second. Just as the current in the primary coil of a common transformer will induce current in the secondary coil when shorted, the alternating magnetic field from this primary current now induces alternating current in electric conductors that happen to be located in the vicinity of the path over which the 'plane is flown. This induced secondary current in each conductive section of the ground causes, in turn, an alternating magnetic field, secondary field, which disturbs or dampens the normal alternating magnetic field from the primary loop flown by the 'plane. These secondary fields are then picked up and recorded by the help of detecting solenoids, amplifiers, and recorders carried in the 'plane. By closer study of such a secondary field it is possible to localize the secondary current causing it and, thereby, the conducting body that contains the secondary current. In the 'plane are continuously recorded, besides the amplitude or intensity of the field, also the phase, which is a measure of how much the recorded secondary field is out of step with the primary field.

Jan 1, 1950