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By Peter Murphy

This report (arid related appendices) provides a description of the functional design specifications, engineering design specifications, and program of instruction for development of a training system for dragline equipment operators. Based upon a task analysis and training system analysis prepared under Phase I, Phase II efforts expanded upon and refined the functional design specifications. The training hardware components have been developed to a point shy of system fabrication. A detailed outline of the porgram of instruction and content sequence has been prepared. The objective of the training system described in this report is to provide new operators of dragline equipment with the requisite skills and knowledge to assure cost-effective development and an adequate supply of our human resources.

Jan 1, 1976

The excavation of ramps and tunnels often requires high-speed development with (or without) the use of high-energy mining equipment such as loaders, dump trucks, TBMs and roadheaders. This high-speed development creates a challenge in terms of providing a safe and productive working environment. For example, heat from continuously exposed surrounding rock, heat from broken rock, heat generated by mining equipment, potential in flows of hot ground water, pollution from associated diesel equipment and the distance of the advancing face from fresh through-ventilation all have to be taken into account when designing ventilation systems for high-speed ramp and tunnel developments. This paper discusses methods of achieving acceptable environments at the face and along the length of the tunnel. The methodology has been successfully implemented in the development of long (up to 20 km) TBM drives in the Lesotho Highlands Project and in mining projects in hot rock using drill and blast methods as well as mechanized methods using continuous miners and roadheaders. The determination of heat loads includes calculation of the heat flow within the surrounding rock, evaluation of the operating cycle of the equipment and the contribution to the overall heat load of the broken rock as it travels out of the tunnel. The determination of heat loads from surrounding rock in new tunnels required a modification of the algorithms generally used for established excavations. The paper also examines the use of, for example, mobile duct and fan systems to ensure that fresh air is delivered to the specific areas where workers are located.

Jan 1, 2000

By Steve Cole

"The economic and strategic importance of PGE bearing deposits is fuelling renewed exploration and development efforts in the precious metals mining sector.This paper presents a review of the various techniques used in the processing of PGE bearing ores, from primary benificiation to processing routes for the different flowsheets that have been developed amongst current producers. Recent innovations such as preconcentration of ore using gravity separation, recent trends in flotation circuit design and the development of hydrometallurgical routes for the direct treatment of flotation concentrates without the need for smelting will be discussed. Data from recent projects will be presented to illustrate common characteristics of PGE ores and concentrates.INTRODUCTIONThe six platinum-group elements (PGE): ruthenium, rhodium, palladium, osmium, iridium and platinum, together with gold and silver, are considered to be ""precious"" metals. The recent spike in platinum and palladium prices coupled with the projected increase in demand for the metals has fuelled a spate of exploration and new projects in the PGE sector. Historically primary producers of PGE metals have controlled the flow of information relating to the mining and processing of these ores into the public domain. Very little published information relating to individual operations and processes is available in comparison to the abundant literature relating to other metals.The purpose of this paper is to provide a general overview of the issues relating to the processing of PGE ores. Each topic discussed could easily be the topic of a paper or book and so in many cases only the surface of the topic will be scratched. An attempt has therefore been made to provide as many references as possible.This paper discusses the classification and location of PGE ores, the mineralogical factors that affect recovery of PGE's, methods currently used for recovering PGE's and process trends in PGE metallurgy."

Jan 1, 2002

By Victor Raul Alarcon

The Ilo Refinery was commissioned in 1975, with a cathode production capacity of 150,000 tpy. In 1994, Southern Perú Copper Corporation (SPCC) purchased the Refinery from Minero Perú SA. Subsequently, in November 1999, Grupo Mexico acquired control of Southern Perú. The anode production facility is located at the Ilo Refinery. A number of effective operating and quality control practices have been developed that have improved anode quality, as well as increasing anode production capacity to 350,000 tpy. These, and other optimization actions have allowed for a current density increase from 213 A/m2 to 275 A/m2, while maintaining current efficiency at 98% and sustaining the high quality of the cathode. The paper will outline the scope of operational practices in the Anode Plant and provide some discussion on the Ilo Smelter modernization project, and the resulting impact on the existing anode plant.

Jan 1, 2005

By John H. Gasper

The success of steep slope (>20°) contour mining depends on many factors. Most important is the selection of the mining method that best suits the premining site conditions environmentally and economically. These conditions can be divided into three categories: • Geometric conditions - machine limitations, slope stability restrictions, erosion capacity; • Physical conditions - material properties, rock strengths, ability to dig, driving surfaces; and • Chemical conditions - acid-base relationships, blending or selective placement of overburden. This article incorporates these conditions by conceptually modeling compliance-oriented contour mining methods, particularly haulback methods, using the combined front-end loader (FEL)/ truck, tractor/scraper, and FEL-truck and scraper. Engineering analyses, including machine selection, sequencing, ease of varying production rates, slope requirements (for stability and running surfaces) and drainage requirements can be performed after the geometric constraints dictated by in situ conditions and regulatory requirements have been conceptualized. Once all generalized geometries have been established, reduction to idealized, three-dimensional views is achieved. These are then reduced to two-dimensional symbolic models, mainly plan views but also elevations and sections. Equipment activities and operations are then conveniently overlayed. Without this simple, two-dimensional reduction, technology transfer remains awkward and non-analytical.

Jan 1, 1991

By William C. McBee

Sulfur concretes have been developed by the Bureau of Mines as construction materials with physical and mechanical properties that suit them for use in acid and salt corrosive environments where conventional concretes fail. Mixture design methods were established for preparing sulfur concretes using different types of aggregates and recently developed mixed-modified sulfur cements Bench-scale testing of the sulfur concretes has shown their potential value. Corrosion resistance, strength, and durability of sulfur concrete are superior to those of conventional materials. Field in situ evaluation tests of the sulfur concretes as replacement for conventional concrete materials are in progress in corrosive areas of 24 commercial chemical, fertilizer, and metallurgical plants.

Jan 1, 1983

By Jose A. Delgadillo

The hydrocyclone problem has been a challenging task for the last 30 years. In the 80’s and 90’s Computational Fluid Dynamics solution to this problem began to appear. These were unsuccessful due to over simplification. In the past 3 dimensional solution with ?-e model and Reynolds Stress Model have been published. In this paper RSM and ?-e models are compared with velocity profiles measured in 75 mm and 250 mm diameter hydrocyclones. It is shown that results are not satisfactory with RSM or ?-e and that a model called Large Eddy Simulation is needed to describe velocity profile evolution and size classification.

Jan 1, 2005

By A. H. Swart

Unplanned stope panel collapses occur on most near-surface and shallow mines in South Africa. Although these incidents often occur during blasting, they pose a major threat to the safety of underground workers and the economic extraction of orebodies. Most stope panel collapses occur due to excessive panel lengths (resulting in excessive stope spans) that are not designed according to a systematic design procedure or methodology. Instead, panel lengths are often dictated by the equipment in use and by previous experience under similar conditions. Hence, a rock engineering design methodology for the design of stable stope panels between pillars is of vital importance for optimum safety and production in shallow mining operations. Using the proposed design methodology described in this paper, rock mechanics practitioners and mine planners should be able to identify and quantify the critical factors influencing the stability of stope panels. The critical factors should then be used as input to the design of stable stope panels that will provide the necessary safe environment for underground personnel working in stopes. The proposed design methodology is an iterative process, which includes aspects such as rock mass characterization, estimation of rock mass properties, identification of potential failure modes, consideration of appropriate stability analyses and other elements of the rock engineering design process. This process continues after implementation. During monitoring, new data should be included in the database and the design process repeated on a regular basis. Design approaches included in the proposed design methodology include empirical methods such as different rock mass classification methods, analytical methods such as elastic and Voussoir beam analyses, kinematic analyses, probabilistic analyses, and numerical analyses. Keywords: stability, stope panels, design methodology, hardrock mines, shallow mining operations

Jan 1, 2005

By C Verdel, M Lee, A Oorloff, K Welsh

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Thomson Orogen is a large but poorly understood element of Queensland geology. Extensive cover conceals the Thomson Orogen at depth, thus limiting studies to a small number of surface exposures. Previous studies of the northern Thomson Orogen have been restricted to the largest of these exposures in the Anakie Inlier and Charters Towers Province. Less extensive exposures, including Mt McLaren in east-central Queensland, are largely overlooked and poorly documented. Fieldwork suggests that Mt McLaren is a west-tilted fault block of Thomson Orogen metasediments that are at least 2200 m thick. The substantial thickness of these sediments (which we have named the Mt McLaren Formation) and the consistent shallow marine facies throughout the block suggest deposition in an actively subsiding basin. Initial dating of detrital zircons places deposition of the Mt McLaren Formation in the Late Cambrian to Early Ordovician, allowing correlations with formations of similar composition and age in the nearby Anakie Inlier and Charters Towers Province. Both of these areas have a long history of mining and exploration for gold and base metals, suggesting that correlation of basement sequences across these areas could be beneficial for exploration models of the Thomson Orogen as well as for tectonic models of eastern Australia.CITATION:Lee, M, Verdel, C, Welsh, K and Oorloff, A, 2015. Stratigraphy of the Thomson Orogen – new insights from Mount McLaren, north-east Australia , in Proceedings PACRIM 2015 Congress, pp 551–556 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Youngtak Ko, Wonnyon Kim

Korean contract Mn-nodule field in the NE equatorial Pacific is composed of seven sectors showing average water depths of 4,513 - 5,025 m. Of the various factors controlling the property of Mn-nodules, water depth has a potential linkage to chemical composition, shape and abundance of nodules. To clarify such a possibility, we review more than 20 years of research data in one of the northern sectors (hereafter KR1) where there is a marked contrast in water depth. High-resolution seabed mapping clearly separates a northern part from a deeper southern part, cutting across the middle of the KR1. In terms of nodule occurrence, manganese nodules in the deeper north are comparatively larger (2-4 cm) with rough surface (t-type) and discoidal shape (D-type), while those in the south are generally small (<2 cm) with smooth surface (s-type) and irregular shape (Itype). In addition, the nodules in the north have higher metal contents including Cu, Mn and Ni. Such connections of water depths to nodule occurrence and metal contents are commonly observed in the Korea licensed Pacific nodule fields. However, the relation between nodule abundance, size and water depth may be a different story. In KR1, nodule abundance and size are probably controlled by morphological features especially in the north. Seamounts in the north continuously provide rock fragments as new nuclei for the nodules. As a result, the nodules can not grow larger than 2 cm and show the shapes of newly formed nodules (i.e., smooth surface and irregular shapes). Such an interpretation is supported by anomalously high backscattered intensities in the side-scan sonar image map of the north, which possibly reflects a younger generation of magmatic activity.

Sep 1, 2014

By M. K. Eryadin, I. Yildirim, R. Asmatulu

Novel dewatering aids were tested on various coal samples from the U.S. and Canada in laboratory and pilot-scale filtration experiments. The reagents substantially improved the dewatering kinetics and reduced the cake moistures. The cake moistures were typically reduced from 20-30% by weight to 8-14% range in vacuum filtration. When the reagents were used in conjunction with a pressure filter, higher degrees of moisture reductions were achieved. In the present work, the novel dewatering aids were tested using different types of pilot-scale vacuum filters. The results were consistent with those obtained in laboratory experiments.

Jan 1, 2003

In the Bendigo district, with its large number of comparitively small leases worked by separate companies, we might naturally expect to find many different arrangements of winding machinery and, as a matter of fact, there are steam winches, old portable engines, single and duplex geared engines, twin engines on the first motion, and in one instance a single engine on the first motion, all employed for hauling purposes from depths of 1000 feet and over.It would be impossible in the compass of this paper to discuss at all fully the various arrangements of winding gear employed on the field the writer can simply refer to some of the more prominent features, in the hope that the information may prove of interest and benefit to the mining community. In criticising our machinery it must be remembered that when many of the plants in use at the present time were erected, they were not intended to wind from more than one third of the depths now common on the field; but so long as the machine could be made to haul a tank of water from the bottom of the shaft it has remained, the greater power required being obtained by increasing the piston speed and altering the gear wheels to suit. The consequence is, of course, that in some of our mines the speed of winding is painfully slow this feature, however, though certainly not consistent with modern ideas of economical mining, does not so seriously affect Bendigo as it would other fields, for the comparatively small quantity of stone to be raised from a given reef by some...

Jan 1, 1902

By William Wilkinson, Vladisla Kecojevic

Current three-dimensional (3D) computer design technology leveraged into drill and blast planning and operations is changing the way engineers and operations approach drill and blast design. Additionally, Global Positioning Systems (GPS) technology that is now readily available to the civilian population is being implemented into the mining sector with a variety of new products specifically designed for drill and blast operations. The objective of this article is to discuss the steps involved with 3D Computer-Aided Design (CAD) of drilling and blasting, and the benefits such a design can provide in conjunction with GPS and drill monitoring systems.

Jan 1, 2004

By Wenming Wang

Recycling of retired cadmium telluride (CdTe) photovoltaic (PV) modules has attracted attention due to new European environmental regulations. Recycling tellurium from CdTe PV modules is becoming more important because of the low availability of this metal. We investigated several treatment paths for reclaiming tellurium from solutions obtained from leaching fragments of CdTe PV modules. Our experiments showed that conventional soda ash neutralization/hydrolysis methods recovered only 50~60% of tellurium. However, by appropriately combining neutralization and sulfide precipitation, almost all the tellurium present in the leaching solution was precipitated and recovered; the concentration of tellurium in the processed solution was reduced from 900-1000 mg/L to less than 1 mg/L, yielding a tellurium recovery greater than 99%. This method can be incorporated in the scheme of recycling spent CdTe PV modules and manufacturing wastes. It may be also an alternative to the current operations for removing tellurium from copper anode slime leaching solutions.

Jan 1, 2006

By V. Arslan

The primary advantage of using oxalic acid is in the formation during leaching of soluble complexes that are both photo-chemically and microbiologically degradable. In this study, chemical leaching and bioleaching methods were used for quartz sand. Using the ANOVA-Yates test technique, the effects of solids rate, temperature and oxalic acid rate were investigated using chemical leaching experiments. Solids rate and temperature were effective parameters on the chemical leaching. After the tests, the removal of Fe2O3 increased to 97.02%. Finally, the iron content decreased from 0.315% Fe2O3 to 0.0094% Fe2O3 in the leached quartz sand. The effect of pulp density was investigated on the bioleaching experiments. The bioleaching of iron oxides by Aspergillus niger resulted in removal of 47.70% of the total iron in the quartz sand, and suggested that this strain has not a good ability to remove iron impurities from quartz sand in comparison with chemical leaching. The iron content decreased from 0.315% Fe2O3 to 0.164% Fe2O3 in the bioleached quartz sand.

Jan 1, 2009

By L. C. IlsLey, J. W. Paul, E. J. Gleim

Flame safety lamps have been used in gaseous mines since the Davy lamp was introduced, more than 100 years ago. During the last decade the flame safety lamp has been rapidly replaced by the electric lamp as a device for illuminating the miner's working place; in the United States the electric cap lamp has been widely adopted. For example, in 1911 approximately 45,000 flame lamps and no electric lamps were being used in the Pennsylvania bituminous mines, which were then producing 35 per cent of all the soft coal mined in this country; by 1918 the flame lamps had decreased to 17,000, whereas electric lamps-mostly of one maketotaled nearly 48,000. In Great Britain during the same years the total of 723,934 flame lamps decreased to 590,185 and the electric lamps gained rapidly from 4,298 to 156,521. No later reliable figures are at hand. However, before the flame lamp becomes obsolete, it is fitting that the Bureau of Mines compile a permanent record of a device which has served the mining industry for more than three generations, and not only made possible the development of entire districts that otherwise could not have been worked but undoubtedly saved the lives of thousands of underground workers. Flame safety lamps are capable of doing more than the name indicates. First, under normal conditions, they can be used in a mine atmosphere that contains an explosive mixture of gas and air without great danger of exploding such a mixture, though such use of a flame lamp should not be permitted. Second, to an experienced man they indicate percentages of gas much lower than the explosive limit, and thus can be used to indicate to workers the approach of an unsafe condition in the mine atmosphere. Third, flame lamps will not burn in an atmosphere greatly deficient in oxygen, and they therefore warn the users of such deficiency in time to withdraw to a place of safety. Flame safety lamps are still used rather widely in the United States for general illumination and to a still greater extent for detecting gas. Many coal-producing States require fire bosses to use these lamps in gaseous mines, and the regulations of several States specify that a gIven number of such lamps be kept available for emergency service.

Jan 1, 1924

By A. A. B. Douglas

In this paper the origins of the mortar intruded concrete concept and its development and application in the construction of watertight bulkheads in South Africa are described. The events leading to the commissioning and execution of the West Driefontein Experimental Plug and the Virginia/Merriespruit Boundary Plugs, and their roles in the proving of the technique, follow. The development of the first Transvaal and Orange Free State Chamber of Mines Code of Practice for Mortar Intrusion Concrete for Underground Plugs and Bulkheads, Johannesburg, November 1962,is explained. The saga of the October 1968 flood and subsequent salvage of the West Driefontein Gold Mine is recounted. The paper concludes with mention of the validation programme carried out for the Placer Dome Western Areas Joint Venture and their South Deep water barrier programme.

Jan 1, 2006

By L. P. James, W. W. Atkinson

Utah has produced about one billion troy oz. (31.7M tonnes) of silver, more than any U.S. state except Idaho. Several very high grade ore systems, now closed, occur within large polymetallic limestone-hosted districts related to plutonic complexes. These Utah mines fed several major lead smelters for nearly a century. Interaction of magmatic chloride-rich fluids with carbonate rocks localized significant bonanzas within these districts. A low sulfidation state was produced in the fluids by their passage through limestones. The Bingham porphyry mine has also yielded more byproduct silver than other porphyry copper-gold systems. Away from exposed intrusive rocks, some large silver-only systems occur in Mesozoic sandstone and in caldera-related veins in volcano sedimentary rocks. Thick permeable latest-Proterozoic basement meta quartzite sequences present beneath western Utah may have been important, as perhaps they were in the Coeur d’Alene district of Idaho, in providing chloride and silver-rich ore fluids. However, it is clear that specific Tertiary magmatic events played an essential role in the evolution of the Utah silver-rich metallogenic province. The largest silver districts in the state are genetically related to porphyritic plutonic rocks.

Jan 1, 2000

By John D. Watson

The results of extensive field tests of a new and powerful method of hard rock excavation are presented in this report.* The method, known by the acronym REAM (Rapid Excavation and Mining), employs high velocity, smooth bore cannons to efficiently deliver energy to the rock and has been demonstrated for underground tunneling, drilling, surface benching, scaling, and secondary breakage in hard granitic rock at the Hope Valley Mine test site in California. Solid projectiles made from inexpensive materials such as concrete or steel, and weighing from 8 to 12 pounds, are launched by conventional high speed cannons and impact the rock at velocities of 5000 feet per second--an impact energy of about 4 million foot pounds (Figure 1). The energy applied at peak pressures of nearly 2 million psi over a period of tens of microseconds breaks down the rock by a complex mechanism of crushing, spalling, and initiation and propagation of fractures produced by the interaction of successive impacts and free surfaces. The main objective of the tests during 1973 was a demonstration of controllability of the underground operation of a silenced cannon. To accomplish this objective a 90-mm cannon

Jan 1, 1974

By R J. Holmes

The procedures and equipment used for sampling iron ore process streams have generally improved in recent years. However, there are a number of areas where significant issues still commonly occur, including sampling high capacity streams, sample cutter design and operation, division of primary increments at the secondary sampling stage, the performance of crushers installed to reduce the particle size prior to sample division, and the sample mass that is retained at each sampling stage. These issues of non-conformance with correct sampling principles are caused by factors such as increasing the speed and loading of conveyor belts to increase throughput, which changes the trajectory of the ore stream and may result in an inability of the sample cutter to handle the increased flow rate without sample loss. Failure to sample the entire primary increment stream at the secondary sampling stage is also a common issue as well as failure of crushers to provide crushed products of the required particle size due to ongoing maintenance and/or adjustment issues. These common pitfalls can all be addressed through careful attention to detail.CITATION:Holmes, R J, 2017. Common pitfalls in sampling iron ore, in Proceedings Eighth World Conference on Sampling and Blending , pp 261–264 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017