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By J. van Deventer

Ion exchange is widely used in hydrometallurgical operations for the recovery and purification of valuable metals. Special chelating resins have a high affinity for specific elements, allowing the selective removal of low levels of impurities from a background of highly concentrated valuable metal. Solvent-impregnated resins have been added to this group more recently, expanding the treatment options. These products find application in the purification of cobalt-rich liquor prior to the production of high-purity metal or metal salts. Impurities in copper-cobalt circuits that are typically targeted by ion exchange include iron, uranium, copper, zinc, nickel, bismuth, and antimony. Ion-exchange resins can also be used to treat tailings, thereby recovering additional valuable metal and improving the Environmental and Social Governance credentials of the operation. This article takes a look at various applications of ion exchange in copper-cobalt operations

Jan 1, 2023

Case 1: A driller raised a drill rig mast into a 7200-volt overhead power line. Both he and his helper were killed. Case 2: A driller-helper was pulling a winch cable toward a stack of drill steel when the cable contacted a 12,000-volt power line. The helper was killed, and the driller at the rig controls was severely injured. [ ]

Jan 1, 2006

By V. Mathebula

Paper written on project work carried out in partial fulfilment of B. Tech (Mining Engineering) degree The purpose of this study is to establish whether to mine the Bottom of Pit (BOP)/TOB 4 reserve before the commencement of the Block Cave or whether this should be disregarded and the reserve be extracted at the end of the life of the Cave. The primary goal of this report is to investigate and propose a practical mining method to safely extract the reserve given the set constraints. This report quantifies the additional revenue the TOB 4 will contribute to Finsch?s overall NPV thus enhancing Finsch?s business case and strategically enhancing the SBP. Several underground mining options have been investigated. The proposed mining method includes the installation of a series of extraction tunnels below the TOB 4 reserve from 53 level, with a slot access tunnel system. Ground will be loaded by LHDs from the draw points and tipped into 50-ton dump trucks at a transfer point, from there the ground will be transported to 53 level No. 1groundpass where it will join the existing ground-handling system. Primary development is scheduled to begin October 2002 and last for a period of approximately 7 months until early April 2003.The production is broken into 4 phases. Phase 1 is scheduled to begin mid-April 2003. The final production phase will be completed by November 2005. The production scheduling has been designed in order to remain ahead of the Block 4 undercut in order to ensure stability and safety. Due cognisance was taken of the health and safety of all employees concerned during the design of the mining and ground-handling processes for the Bottom of Pit. As far as is reasonably practicable, the BOP was designed and will be constructed and equipped to provide conditions for the safe operation of machinery and a healthy working environment for people underground. Relevant requirements of the Mine Health and Safety Act regulations pertaining to mining operations have been identified and adhered to during all phases of the design process.

Jan 1, 2004

By Tuncel M. Yegulalp

The objective of this study was to categorize mining operations in the stone, and sand and gravel industries into areas of similar ground control functions and define initial factors affecting operational safety in each area, by means of utilizing publicly available data, telephone interviews and on site observations. The findings and recommendations presented in this report are based on the information collected during the two phases of the project. They also contain, in part, the collective qualitative opinion of the operators with respect to government rules and regulations on ground control safety and the implementation of these rules and regulations by government inspectors.

Jan 1, 1981

In recent years there have been many changes in mine ownership due to the on-going rationalisation towards larger mining companies. Larger companies inevitably find it hard to manage small mining operations and in many cases smaller mines do not fit corporate resource, production and profit criteria. Smaller companies are more suited to managing these medium or small scale mines and are tendering for the purchase or lease of mines that larger companies wish to dispose of. In addition to these factors there has also been a trend (especially in Western Australia) for mines to continue operating at ever increasing depths. This in turn has led to more mines operating in high stress environments and experiencing damaging seismicity. Assessing the viability of seismically active mines from a takeover or purchase point of view should involve analysing the risk profile of every aspect on mining that could be affected by adverse seismicity. This includes assessing current and alternative mining methods, mine designs, support systems, extraction sequencing, monitoring and blasting. This paper includes discussion on items that need to be assessed when considering the purchase of seismically active mines, with experience gained from some recent studies in Western Australia. In these cases it was apparent that quantification of previous seismic history on itÆs own was a totally inadequate method of assessing minewide seismic risk potential. A more holistic approach is required, taking into account all aspects of relevant data, all the minewide effects of seismic activity and all possible means of mitigating those effects.

Jan 1, 2002

By F. Stober, D. Wanblad, J. Ndlovu, L. R. Nelson, L. P. S. de Villiers

The single six-in-line furnace of the Polokwane Smelter is the largest installed high-intensity furnace for platinum group metals (PGM) base metals sulphide smelting in the world. The furnace employs state-of-the art technology to deliver a planned throughput of 650 000 t/a dry concentrate at a design 68 MW power input. This furnace, at double the capacity of previously existing PGM furnaces, offers low unit operating and capital cost through the resulting economies of scale. Key features of the design include:

Jan 1, 2005

By Germán Mallén

Como parte de los estudios línea base realizados por MWH Perú S.A. para el proyecto aurífero Chucapaca de las Canteras del Hallazgo en el distrito de Ichuña de la región Moquegua, Perú, se investigó el origen de boro, alta salinidad y otros componentes que perjudican la aptitud de los ríos Ichuña y Tambo para irrigación y otros usos. En este sentido, se encontró que la calidad de agua es perjudicada principalmente por altas concentraciones de sodio, entre otros, precipitándose como hidróxidos de estos metales debido al pH neutro en el río. En ese sentido, el presente texto describe la relación de este impacto químico con los manantiales entre el Cerro Chucapaca y el cañón del Río Ichuña/ Alto Tambo, ubicados al Norte de Moquegua, donde presentan la característica distribución de diferentes tipos de aguas volcanogénicas sobre un sistema de convección hidrotermal de agua meteórica profunda reciclada, calentada y movida por una cámara magmática andesítica que aporta calor y gases.

Sep 21, 2013

By J. Dong

"Xanthate is a sulfide collector that has been widely used in flotation for almost a century. It is inexpensive, easy to synthesize and apply, and produces good metallurgy in the right applications. However, a major drawback of xanthate is that it decomposes easily and generates CS2 gas in transportation, storage and operation, which can be harmful to human health. Also, excessive xanthate in tailings pond leads to toxicity of the process water and potential damages to aqua-life systems. New regulations in Ontario require that the TWA (time-weighted-average) value of CS2 in the work place is below 1 ppm, which is 1/10 of the previous limit. The stringent regulation may eventually sweep other regions of Canada with the increased awareness of healthy working conditions and environment protection. Therefore, it becomes very important to find xanthate replacements which will be “green”, i.e., environmentally friendly.In this research work, a systematic procedure is used for collector evaluation using the Sudbury nickel sulfide ores from Vale’s Ontario operations, starting with the collector properties (MSDS) evaluation, followed by batch flotation tests, miniplant tests, plant trials and economic evaluation. It is found that the most promising xanthate replacement is dithiocarbamate.INTRODUCTIONSulfide mineral flotation has been practiced since the early 20th century. Its industrial importance is well recognized as mineral concentrates from flotation can be economically smelted and refined to provide primary metals. Collectors play a vital role in froth flotation. There are reagents possessing both a polar group that binds them to the mineral surface and a nonpolar group that is oriented away from the surface to attach air bubbles. The introduction of xanthate as a sulfide collector in 1925 was a remarkable development in froth flotation (Keller, 1925). It is low cost, easy to synthesize, water soluble, simple to control in application. Most importantly, it has strong capability and usually good selectivity for sulfide mineral flotation, which have been keeping its application prominent for almost a century."

Jan 1, 2011

By H. A. Oliveira, A. Azevedo

Physical and chemical characterization and solid/liquid separation of turbid waters from a river affected by an iron tailing rupture disaster (Gualaxo do Norte River, Brazil) were studied at bench scale. Parameters such as turbidity, pH, surface tension, electrical conductivity, total suspended solids (TSS), particle size distribution (micro- and nanoparticles), and zeta potential were analyzed from samples collected at three different river depths. The results in all samples showed the presence of micro- and nanoparticles, ranging in diameters from 100 nm to 200 μm. Best results for flocculation and settling were obtained at pH 7.5, through an innovative combination of eco-friendly reagents: (i) ferric hydroxide precipitates (10 mg L−1 Fe3+) to sweep (enmesh) the dispersed solids and (ii) gelatinized starch (5 mg L−1 ) to form large flocs. The results showed removals between 90 and 100% of total suspended solids (micro- and nanoparticles), resulting in clear water with residual turbidity < 7 NTU. It is believed that this innovative alternative has a high potential for flocculating and treating the turbid water at Gualaxo do Norte River, assisting the water treatment stations.

By H. A. Oliveira, A. Azevedo

Physical and chemical characterization and solid/liquid separation of turbid waters from a river affected by an iron tailing rupture disaster (Gualaxo do Norte River, Brazil) were studied at bench scale. Parameters such as turbidity, pH, surface tension, electrical conductivity, total suspended solids (TSS), particle size distribution (micro- and nanoparticles), and zeta potential were analyzed from samples collected at three different river depths. The results in all samples showed the presence of micro- and nanoparticles, ranging in diameters from 100 nm to 200 μm. Best results for flocculation and settling were obtained at pH 7.5, through an innovative combination of eco-friendly reagents: (i) ferric hydroxide precipitates (10 mg L−1 Fe3+) to sweep (enmesh) the dispersed solids and (ii) gelatinized starch (5 mg L−1 ) to form large flocs. The results showed removals between 90 and 100% of total suspended solids (micro- and nanoparticles), resulting in clear water with residual turbidity < 7 NTU. It is believed that this innovative alternative has a high potential for flocculating and treating the turbid water at Gualaxo do Norte River, assisting the water treatment stations.

By Thomas C. Shapiro

This is the second in a series of articles on microcomputers and applications in the minerals industry. The first article (ME, Feb., page 129) discussed microcomputer terms and concepts. This article will discuss software for geology and mining. The third article will cover plant, administrative, and geotechnical software applications. Introduction Geology and exploration are areas where computers have a natural fit. Large volumes of data need to be tabulated, evaluated, and made into maps and reports that allow geologists and management to make a decision on a project or mine. Until recently, the programs that performed these tasks were cumbersome and not user friendly by any stretch of the imagination. Learning time to become an expert in these programs typically would be six months or more. The computers needed to run these programs are expensive mainframes. Several years ago, the use of minicomputers became popular because of their lower cost. Programs were adapted to fit these smaller machines and became friendlier. With the advent of micros, many programs. were rewritten and used the screen capability more effectively, thus providing a real advance in user interface. Programs and Price The definition of micro, mini, and mainframe is becoming blurred. For the purposes of this article, micro refers to either an eight- or 16-bit computer, costing less than $10,000 and, more typically, under $5,000. Mini refers to a 16- or 32-bit computer that typically costs more than $25,000. Mainframe refers to a 32-bit or larger computer that costs more than $250,000. There is a large gray area between micros and minis, and minis and mainframes. Technology and prices are changing so fast that the traditional definitions have become almost meaningless and price has become a better guide. With the arrival of the minicomputer, costs for hardware began to fall, but the programs have tended to remain unfriendly. In some cases, the minicomputer acted as a front end to the mainframe. Cost of both the programs and minicomputers could easily run a minimum of $70,000. A total cost of $200,000 would not have been out of line. The average geologist and company would have a great deal of difficulty justifying such a purchase. The advent of the microcomputer has changed all that. For $3,500 to $5,000, one can buy a 16-bit micro and a printer. Plotters with six pens are available for $2,000 that will produce a 280- x 430-mm (11- x17-in.) map. For several hundred dollars, software is available to act as a word processor, an economic spread sheet, or to perform ground water calculations. In fact, some programs are available for free. Some of these programs are relatively easy to learn. In addition, programs are being developed daily that are easy to use. More importantly, large programs that once ran only on mainframes are being converted

Jan 3, 1984

By D Kepert, M Absalom, N Nitschke, C Fowers

The discovery of the Nyidinghu Iron Ore Deposit totalling 2.46 Bt of resource continues FortescueÆs highly successful exploration record of discovering multi-billion tonne deposits under cover with little to no surface expression. Since inception in 2003 Fortescue have discovered and delineated the Christmas Creek and Cloudbreak deposits in the Chichester Range totalling 3.38 Bt and 3.25 Bt in the Solomon region. Together with other deposits Fortescues resource portfolio now approximates 10 Bt of hematite - goethite mineralisation.The Nyidinghu deposit is situated on the southern margin of the Fortescue Valley, 35 km south of FortescueÆs Cloudbreak mining operations on the north margin of the valley. Nyidinghu comprises approximately 70 per cent BID martite - goethite mineralisation hosted by the Brockman Iron Formation and 30 per cent CID beneath alluvial outwash of the Weeli Wolli Creek in to the Fortescue Valley. Minor DID mineralisation occurs at the deposit margins.BID mineralisation is strongly controlled by the pre-existing NE/SW trending Weeli Wolli Fault system and bounded to the north by the Poonda Fault. Both fault systems are interpreted to have had a long and complex history commencing pre Ophthalmian Orogeny (ca 2.2 Ga) and remaining intermittently active through the Proterozoic.CID at Nyidinghu is the downstream continuation of the combined Weeli Wolli/Marillana CID palaeochannel system being mined by Rio Tinto and BHP Billiton at Yandicoogina and Yandi, respectively.Exploration commenced in August 2010 with the inaugural resource announcement of 1 Bt being made just six months later. To date over 1700 RC and 85 diamond core holes have been drilled forming the basis for the resource of 2.46 Bt and ongoing feasibility studies. Current exploration activities continue to delineate new mineralisation at Nyidinghu with an ultimate target tonnage of 3 Bt.CITATION:Fowers, C, Kepert, D, Absalom, M and Nitschke, N, 2013. Discovery, geology and structural setting of the Nyidinghu iron ore deposit, Hamersley Province, Western Australia, in Proceedings Iron Ore 2013 , pp 81-90 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

Oil sands processing generates huge volumes of slurry, known as tailings, that is being stored in tailings ponds. The volume of produced tailings is a very important factor in oil sands surface mine planning, because the available area for dam construction is limited to the lease areas. On the other hand, oil sands operators cannot leave mine sites without reclaiming the tailings ponds. Since most of the reclamation material is generated in either oil sands mining or processing, it is reasonable to include reclamation material requirement as part of long-term mine planning. In this paper, an integrated optimization framework is proposed to maximize the net present value (NPV) of the produced oil sands, with respect to tailings capacity constraints and reclamation material requirements. A mixed integer linear programming (MILP) model is developed to find the optimal solution for long-term mine planning problem. A sample bitumen processing flow sheet is used to formulate the volume of produced tailings, based on Clark hot water extraction method. To verify the proposed model, it is coded in Matlab and run using CPLEX. Run results for real-case oil sands dataset show that the optimal production schedule meets material requirements for reclamation, tailings volume is within tailings capacity range in all periods and the production schedule follows the predetermined horizontal direction.

Feb 27, 2013

By N. P. Kripakov

Results of a complex three-seam interaction analysis in a western U.S. coal mine are presented. The physical situation simulated by the models represents the development of a set of entries underneath two previously mined seams with all three seams in proximity to each other. The layout and the geometry of the remnant pillars in the upper seams were nonuniform and not always directly superimposed over each other, creating a very challenging modeling problem. The U.S. Bureau of Mines&apos; MULSIM/PC computer code was upgraded and enhanced to perform the required three-seam interaction calculations. Analysis was limited to simple linear-elastic assumptions as only peak stresses were required. Results clearly indicated that stress concentrations in the lower seam increased approximately 100 percent when compared to cases simulating no extraction in the two upper seams. These stress concentrations generally occurred in zones directly below points of highest abutment pressures in the upper seams. Overall, the model results compared favorably with actual documented observed behavior where roof failures were known to have occurred.

Jan 1, 1996

By Gabsoo Kim, Rulin Yang, Dave Kay

Blast vibration data, such as PPV are usually scattered. In many cases, plots of PPV versus the charge weight scaled distance are so scattered that useful trends from different blast designs cannot be identified. The scattering of the data may be attributed to the inaccuracy of the PPV measurement, the definition of the scaled distance from a multiple-hole production blast, and the measurement of distances and charge weights. The error from vibration measurements is one of the major contributors to the scattering of the plots. If accurate monitoring is conducted, improved design options may be identified. This paper documents two case examples that compare different vibration sensor couplings. The first case shows mounting accelerometers at spots that protrude from the ground, compared with the sensors that were mounted on a flat ground surface. The second case compares data from loose-sand buried geophone with that from sensors coupled to the ground using concrete blocks.

Jan 1, 2014

By A J. H Newell

The background and the basis for conducting a Technical Due Diligence are discussed as well as the source information, typical studies and potential limitations. Typical short comings including ‘show-stoppers’ are presented for the metallurgical area, with examples. Issues found in other areas such as geology, mining, infrastructure and financial evaluations are briefly reviewed, highlighting the input and interaction required by metallurgists with these disciplines. A checklist is provided as a guide to maximise the success of a Due Diligence as well as a check on the quality of a Feasibility Study.CITATION:Newell, A J H, 2015. Fatal flaws in technical due diligences, in Proceedings MetPlant 2015, pp 61–77 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By R Castedo, L. M. Lopez, J. A. Sanchidrian

In 2014 the authors presented results from 13 tests made with two blasting seismographs on a vibration exciter. They measured coupling transmissibility as function of frequency (i.e. ratio of the velocity of the sensor mount to the velocity of the ground motion) from 16 to 200 Hz at one or two vibrations levels (5 mm/s or 0.2 in/s, and 20 mm/s or 0.79 in/s) with mounts freely placed, sandbagged, and anchored to a granite slab firmly attached to the plate of a vibration exciter. As the memory capacity of one of the seismographs prevented to cover low frequencies, e.g. 4-16 Hz, a new measuring campaign has been recently made to extend the study down to 2 Hz. In this campaign, two more techniques, in which the sensor mounts were fixed with thermal adhesive or a combination of duct tape and gypsum plaster, have been also investigated from 2 to 200 Hz at 5 and 20 mm/s. Free and sandbagged mounts lead to a weak coupling of the mounts to rock, so that transmissibility depends on the characteristics of the imposed rock motion (peak velocity and frequency). Measurements are accurate only at low frequencies (below 17 Hz for free mounts and 10 Hz for sandbagged) in the tested conditions (velocities up to 20 mm/s). Above these frequencies, ground motion in the measurement can be modified by a factor of 0.16 to 1.22. Anchored, glued and plastered mounts achieve a stiff rock-to-ground coupling, ensuring consistent measurements for the frequencies commonly found in blasting independently of the vibration level and the mount characteristics

Jan 1, 2015

By Graham A. Davis

?The ideas of economists and political philosophers, both when they are right and when they are wrong, are more powerful than is commonly understood. Indeed, the world is ruled by little else. Practical men, who believe themselves to be quite exempt from any intellectual influences, are usually the slaves of some defunct economist. Madmen in authority, who hear voices in the air, are distilling their frenzy from some academic scribbler of a few years back. I am sure that the power of vested interests is vastly exaggerated compared with the gradual encroachment of ideas. . . . But, soon or late, it is ideas, not vested interests, which are dangerous for good or evil.? John Maynard Keynes The General Theory (1936) Policy analysts, economists and others have tradition-ally considered mining and mineral wealth a boon, providing rich countries with the resources needed to sustain their modern industrial economies while helping poorer countries generate the foreign exchange, tax revenues and other assets necessary for economic growth and development. Nevertheless, this conventional view has always had its critics.

Jan 1, 2008

Gary R. Steele is vice president, corporate marketing with Energy Fuels Resources. As such, he knows the global uranium market. The following are some of his thoughts on uranium?s place in the global energy picture. ME: What are Energy Fuels Resources? thoughts on the global nuclear power industry? Steele: The global nuclear power industry is a major contributor to the electrical needs of the world. Though generation by nuclear reactors has primarily attracted attention through the reactor accidents at Three Mile Island and Chernobyl, nuclear power continues to quietly and safely provide power to a growing and power-hungry world population. As of March 2008, 30 countries were operating 439 nuclear power reactors. Nuclear power plants provided about 15 percent of the world?s electricity production in 2007. France leads the world in nuclear utilization, with 77 percent of its power coming from nuclear plants. And Lithuania, Slovakia and Belgium each derive more than 50 percent of their power needs from nuclear plants. For much of the developed world, nuclear generation has already been contributing significantly to the supply of electricity. Additionally, 34 new nuclear plants are under construction in 14 countries. Leading the rush to build new nuclear generating plants are China, Russia and India. Each of these countries is building six new nuclear power plants. These 18 plants, totaling almost 12,000 MW of generation capacity, will require about 7.25 kt (16 million lbs) of U3O8 for their initial fuel load and will consume about 2.45 kt/a (5.4 million lbs/year) for the rest of their operating lives. The rest of the world, outside of the United States, has used nuclear power as a viable and economic generation alternative since the commercialization of utility nuclear reactors. And current activity supports the strong future of the nuclear alternative internationally.

Jan 1, 2008

By Rosaire Emond

Le concept du forage horizontal a été développé voilà de nombreuses années. Différents types de plate-formes permettant le forage horizontal depuis une cheminée ont été conçus par divers manufacturiers ou opérateurs miniers. Entre autres, on connaît bien la griffe de montage Alimak à laquelle peut être fixée une plat-forme sur laquelle est montée une foreuse. En 1992, Ross-Finlay a développé sa propre plate-forme de forage qui à notre opinion améliore la flexibilité du concept du forage horizontal, en augmente la productivité et en diminue le coût d?ensemble tout en assurant une sécurité accrue des travailleurs. Tel que montré à la figure 1, la plate-forme employée à la Mine Kiena est composée d?un toit de protection contre les chutes d?objets et de deux passerelles de forage de forme carrée. Le toit et les passerelles sont fixées à une structure de 6.5 m de longueur équipée de deux assemblages de rouleaux (non montrés à la figure) permettant de faire glisser l?ensemble sur des rails Alimak. L?angle du toit et des passerelles peut être ajusté pour des cheminées dont le pendage varie de 65 degrés à 85 degrés.

Oct 1, 2001