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By D. F. Hambley

"In designing are passes f or underground mines specific consideration should be given to unimpaired flow of broken rock, the dump point, and typical practices f or overcoming operational difficulties. Design features such as branches, bends, and knuckles should also be considered. This paper pro vides engineering information and various criteria for designing are passes, draw points. feeders, and support systems, together with several illustrative examples.IntroductionOre passes are the primary mean s o f vertical transfer of mined ore to the ore bins and loading pocket from which the o re is hoisted to the surface (Fig. 1) . While the words "" ore"" and ""ore pass"" are used here, such transfer systems ca n be used for any broken rock.The most extensive ore pass systems are found in caving and sublevel stoping mines. Extensive ore pass systems are also found in multilevel mines having steeply dipping orebodies. In more flat-lying orebodies , ore pass systems are sometimes used in conjunction with conveyor systems .Two decades have passed since the principles of the flow of bulk solids were formulated (Jenike, 1961, 1964; Johanson and Colijn, 1964; Kvapil , 1965). However, few published papers are available that discuss the design criteria for ore pass systems. Therefore, the aim of this paper is to provide the information necessary for good o re pass design .Rock Flow in Ore Pass SystemsIf an ore pass system is to fulfill its function, the transfer o f material must occur in an orderly fashion and in such a way that the full size of the opening is employed effectively. Apart from un controlled flow at the drawpoint, or outlet , whose design will be considered later in this paper, two occurrences may impede flow in an ore pass, namely:• Hangups due to interlocking arches.• Hangups due to cohesive arches.Prevention of each of these problems will be discussed in succeeding sections of this paper. A third problem piping, is related to the ratio of the drawpoint size to the o re pass size and will be discussed under drawpoint de sign."

Jan 1, 1987

By Jean-Marc Simard, Richard Genest

"La mine Agnico-Eagle, localisée près de Joutel, a été découverte en 1962 par le forage d'anomalies électromagnétiques. Exploitée à partir de 1974, elle a déjà produit près de 30 tonnes d’or à partir de 2 puits, le puits Eagle et le puits Telbel, distants de 1,3 km.Le gisement est situé entre le sommet du complexe volcanique de Joutel, à dominante felsique, et la base de l'ensemble sédimentaire de la rivière Harricana. Ces deux unités ont une extension régionale; elles sont orientées NW-SE avec une polarité NE et des pendages subverticaux. Une faille majeure, la faille Harricana, passe de façon subconcordante au contact de ces deux ensembles.La minéralisation aurifère, de 2 à 5 m d’épaisseur moyenne, est liée a une zone carbonatée, comprise entre des tufs felsiques, argilites et sédiments chimiques (éponte inferieure) et des argilites carbonatées (éponte supérieure). Le minerai est constitué habituellement de 20% de fine pyrite disséminée. L’or est en fines particules associées directement à ces grains de pyrite de texture cataclastique.Deux modelés ont été for mules jusqu' a présent pour expliquer la genèse du gisement: une thèse syngenetique (Barnett et a/.1982) et une thèse épigénétique (Wyman et al. 1986). Cette dernière apparalt comme la plus probable du fait de la présence de la minéralisation dans les zones cisaillées a carbonates secondaires et pyrite cataclastique."

Jan 1, 1990

By W. E. Selnes

Introduction In 1938, a survey conducted by the Ontario Mining Association revealed a rather startling fact. Injuries incurred in chute pulling were more numerous than those from any other single cause. This report prompted Mr. W. B. Paton, then Inspector of Mines for Manitoba, to make a similar survey of the mines of his Province. It indicated that, in Manitoba mines, chute accidents ranked second only to those from falls off roofs and sides. Why has the mining industry been so slow to recognize the dangers of chute pulling? A partial answer may be the lack of any systematic classification of accidents according to their real cause. The result has been to attribute to other causes injuries which were a direct outcome of chute pulling, and, indeed, has made it difficult to analyze accidents in the industry as a whole. Perhaps, too, because chutes are generally located in the comparative safety? of the drifts, there has been a tendency to consider the occupation as not very hazardous. Not until enough statistics were obtained on this particular task could it be appraised correctly. The Mining Association's survey has been most helpful, and latterly the industry has done a great deal toward analyzing the causes of chute accidents and toward determining an effective means of overcoming them. Much, however, remains to be done. An effort will be made in this paper to outline methods which have been found successful in materially reducing the number of injuries. Qualifications of the Chute Puller First of all it must be realized that chute-pulling is a specialized occupation. The men require proper training for the job, just as in other mining operations. Care must, therefore, be taken to choose persons whose qualifications fit them for the job. Chute-pulling is an integral part of the general mining operation and cannot be considered as isolated from the tasks of other workers. One of the essential qualifications of a chute-puller is a sufficient knowledge of mining operations to appreciate the effect his work will have on the safety of others in the vicinity. He must take the necessary precautions, by verbal warnings, by placing barricades and signs, or by personally guarding the chutes, to prevent accidents to fellow workers.

Jan 1, 1947

By B. Dubreuil, J. -M. Lalancette, D. Lemieux

Arsenical bearing deposits are posing an increasing challenge for the mining industry. In particular, mineral processing of arsenical sulfidic ores for base and precious metals recovery tend to produce problematic arsenical tailings. This arsenic being present as sulphide or oxide, tends to dissolve, contaminating surface and underground waters. To meet the environmental regulations, it is often required to stabilize the arsenic in a more insoluble form. Dundee Sustainable Technologies has developed a new patented technology using vitrification of the arsenic oxide in an economical way, giving a stable solid, well below the environmental regulations upon leaching. This technology involves oxidation of As (III) to As (V), by using a low cost natural oxidizer and transformation of the produced arsenic oxide into calcium arsenate, which is not volatile at the melting temperature of the glass. This technology would be advantageously applied on most cases around the world where sulphide concentrates are oxidized in a fluidized bed or smelted.

Jan 1, 2014

By B. Dubreuil

Arsenical bearing deposits are posing an increasing challenge for the mining industry. In particular, mineral processing of arsenical sulfidic ores for base and precious metals recovery tend to produce problematic arsenical tailings. This arsenic being present as sulphide or oxide, tends to dissolve, contaminating surface and underground waters. To meet the environmental regulations, it is often required to stabilize the arsenic in a more insoluble form. Nichromet has developed a new patented technology using vitrification of the arsenic oxide in an economical way, giving a stable solid, well below the environmental regulations upon leaching. This technology involves oxidation of As (III) to As (V), by using a low cost natural oxidizer and transformation of the produced arsenic oxide into calcium arsenate, which is not volatile at the melting temperature of the glass. This technology would be advantageously applied on most cases around the world where sulphide concentrates are oxidized in a fluidized bed or smelted.

Aug 1, 2013

By M. J. MONEA

Canada's only economic high-swelling bentonite deposit is mined in Wilcox, Saskatchewan, by A vonlea Mineral Industries Limited. The bentonite resulted from devitrified and altered volcanic ash released during the Laramide Orogeny. Volcanic ash was deposited in a pre-Cretaceous basin that was formed by salt solution collapse structures. Sedimentary rocks in the Wilcox area belong to the Snakebite Member of the Upper Cretaceous Bearpaw Formation. Bentonite beds are 61 cm, 46 cm and 30 cm thick; these are separated by 365 cm and 182 cm of shale respectively. Saskatchewan bentonite is used primarily in the oil well industry.

Jan 1, 1984

By James R. Kuipers

Center for Science in Public Participation CSP2 ? Organized in 1997 to provide technical assistance to public interest groups on mining and water quality issues ? 80%of effort devoted to direct support of grassroots groups and tribal governments ? 20% of effort devoted to public-oriented education for public, tribal, state and federal regulators, and for industry ? Board represented by public interest groups, at large citizens, and academia ? Professional staff with experience from mining industry, academia and government ? website: www.csp2.org CSP2 Mission Statement The CENTER for SCIENCE in PUBLIC PARTICIPATION provides training and technical advice to grassroots groups on water pollution and natural resource development issues, especially those related to mining. CSP2 seeks to focus the debate on factual issues, as brought to light by its technical analyses, and whenever possible to seek consensus and win-win solutions. CSP2 also performs policy related work with federal and state regulatory agencies on the implementation of water quality, waste disposal, and mining reclamation regulations.

May 1, 2002

By S. M. Moon

Today, underground exploration is spotlighted as an infinitely developable area. For this purpose, many tunneling technologies were created. And until this very day, many techniques are being developed for more efficient underground movement. Although previous technologies have been developed and now being used in various forms like TMB, struck propulsion method and hydraulic propulsion method, it is hard to find a robot type exploring in small scale. But development of small scale underground exploration robot is a promising research subject for its usage in examination of soil, mineral, and subterranean resources, investigation of hazardous regions, and the military. So we developed a robot that can dig and move underground, inspired from the motion of earthworm and mole cricket. Earthworm and mole cricket dig the soil in the front and draw it off backward, so that they can move forward. We developed a mechanism that uses 2 rotating solid of revolution (bits) for pulverizing the firmly united soil in the front and put it inside the body. The bits rotate in the opposite direction of each other. While moving forward, the soil in the front moves along the spiral on the bit and is saved inside the body. The soil saved inside is taken out through an outlet in the back by a ventilation system. The ventilation system on the ground blows through a hosepipe connected to inner part of the robot and the air blows off the soil. The moving mechanism of exploring underground can be classified into 2 parts. One is to fix the blade link on the soil in a form of 4-bar link. The other one is to move forward rotating the whole link. When the blade link system for movement rotates a certain degree, one blade link is fixed, while the other one is folded in. When 2 blade links of different length rotate as it is, different torque is applied on each link. By the law of action and reaction, the link that has larger torque leads the rotation and movement.

Aug 1, 2013

By G. Vibert Douglas

IN a previous paper by Douglas and Gillies (1), a simple field test was given for gold. Later work by the present writers, and by others who have kindly written to us, shows that the test is not as satisfactory as it was hoped. In many cases, the gold mirror is completely obscured by a dense precipitate which, up to the present, it has been found impossible to remove. After many attempts, we have temporarily given up the iodine test and have been working on a simple pyridine reaction based on the work of Putnam, Roberts, and Selchow (2): The ore to be tested is ground to a fine flour. Place half a gram of this powdered ore (an amount that will cover a Canadian ten-cent piece, not heaped) in a six-inch test-tube and add 5 c.c. of aqua regia. The aqua regia. should be made up on each occasion, using four parts of hydrochloric acid and one part of nitric acid, both concentrated. Shake the solution in the test-tube for about one minute and allow to settle until dear. The rime to settle may be 30 to 60 minutes. When dear, a drop of the solution is with-drawn with a fine, dean eye-dropper or capillary tube and placed on à small glass plate. A slide such as is used for mounting rock sections is suitable. Now place an equal sized drop of pyridine solution on the plate beside that of the aqua regia solution to be tested. The pyridine solution, containing nine volumes of hydrogen bromide to one volume of pyridine, can be made up in advance and carried in a glass-stoppered bottle. Join the two drops with a glass thread or fine, dean stick, and allow the merged drops to stand undisturbed. I t is well to place the slide on a piece of white paper so that the presence of the crystals which may form can be easily seen. The time for their formation will vary with the amount of gold present, but the slide should be allowed to stand for at least 30 minutes before negative results are reported. A hand lens of at !east ten magnifications is essential. If gold is present, minute red crystals will form around the margin of the drops as these drops slowly evaporate.

Jan 1, 1938

By G. Beckstead, L. Gormely, R. Zimmer, K. Hanneman, B. Nethery

As part of the EIS and permitting activities for the Pogo Mine in Alaska, a risk assessment study for the water management plan was carried out. The basis for the study was a site water volume and contaminant balance model. Probabilistic modeling was carried out using the @Risk Monte Carlo simulation package to investigate the frequency, quantity, and quality of discharges under varying assumptions. The results were used in discussions with regulatory officials as part of the permitting process for the project. The simulation allows probabilistic modeling of key environmental parameters based on input frequency distributions involving both quality and quantity of flow. When combined with predictions of water treatment plant capacities and removal efficiency, this was very useful for defining the likelihood of important regulatory outcomes. Based on the model, certain project modifications were made. Using the simulation as a basis, ongoing dialog with regulators led to consensus that all potential risks have been considered and mitigated for the Pogo Mine according to their likelihood and severity, and that regulatory requirements would be achieved. The paper describes the model and some of the applications for which it was used.

Jan 1, 2005

By V. Ramachandran

The successful advent of solvent extraction (SX) reagents for copper recovery and improvements in electrowinning of copper to produce LME grade A copper cathode have paved the way for the hydrometallurgical treatment of copper oxide and low grade sulfide ores. This has resulted in about 25-30% of the world's copper being produced today by the Leach-SX-EW process. The obvious next step was to develop processes for the hydrometallurgical treatment of copper sulfide concentrates, as an alternative to a typical smelter-refinery complex. The current paper updates the processes that have been developed to date with emphasis on processes that are being commercialized or that are seriously under consideration for commercialization. Most of the discussions relate to the hydrometallurgy of chalcopyrite concentrates, which account for about 70% of the world's known copper reserves. In summary, in the last thirty years, the hydrometallurgical treatment of copper sulfide concentrates has attained full maturity and will be a serious option to contend with while evaluating any future new copper plant.

Jan 1, 2007

By D. R. Hatton

To obtain sufficient material on which to perform copper-molybdenum separation testwork a variability set of drill hole reject samples amounting to several tons was put together to include the different ore types proportions expected in the copper circuit. The samples were treated in a copper circuit pilot plant and enough mass of bulk concentrate was recovered to conduct copper moly separation tests in the laboratory. Tests consisted of stage flotation reactor (SFR) rougher pilot plant tests, conventional laboratory rougher, cleaner and 4 stage open circuit cleaner tests. The mineralogical liberation analysis of the feed and concentrate was used to model the effect of liberation on the grade-recovery relationship of the different samples. Mineral kinetic parameters for the various samples were determined by calibration to the test data. The copper concentrate results as simulated from previous studies on the same deposit were used to simulate the variability in head grade and throughput expected for the feed to the copper molybdenum separation circuit for each of the first 10 years of production. This variation in feed was then simulated through the separation circuit to obtain optimised molybdenum grade recovery curves to forecast the circuit production for each of the first 10 years. INTRODUCTION Incorporating Geometallurgy into the design for a copper molybdenum separation is especially challenging due to the low mass of final concentrate typically produced during testwork. This is due to the low molybdenum head grades and high overall molybdenum upgrading expected. With molybdenum head grades of around 300 ppm, 1 tonne of copper circuit feed is expected to produce around 300 g of molybdenum concentrate in the plant. In the laboratory however, this may end up only resulting in a few grams. Obtaining sufficient mass for laboratory testing therefore requires starting with a large initial sample and careful testwork planning to maximise the utilisation of this mass. A testwork program was designed to investigate the effect of ore variability on the copper molybdenum separation circuit (here after referred to as the molybdenum circuit). Composite samples were selected to represent the various ore types, copper content, moly content, pyrite content and clay contents expected in the copper circuit feed. These samples were run through a bulk copper pilot plant to create the feed for the molybdenum testwork. The molybdenum testwork consisted of rougher kinetic flotation tests, rougher cleaner kinetic tests, rougher cleaner kinetic tests with regrind, stage flotation reactor (SFR) pilot plant tests, open circuit cleaner tests. These tests were used to calibrate the ore kinetics in the IGS-FLEET model for simulation of the molybdenum circuit performance.

Jan 1, 2019

By P. R. Brito-Parada, G. Bhutani

"The physical processes occurring in flotation columns are very complex as they take place at different scales over a range of sizes and multiple phases. Column design and optimum operating parameters are usually obtained from empirical studies and although progress has been made on its numerical modelling, most column models rely on simplifications that do not fully capture the hydrodynamics. In particular, Computational Fluid Dynamics (CFD) models of the pulp phase in flotation usually assume the bubble population to be monodispersed. While this assumption may be reasonable in some situations, the polydispersed nature of the gas phase can have a significant impact on the predicted flotation rates.Techniques to model size distribution do exist in the literature and have been rigorously analysed in the past two decades for bubble columns, which are very similar to flotation columns from a hydrodynamics point of view. In fact, available CFD models of flotation columns are an extension of bubble column models, sometimes including additional equations for solids treated as passive scalars. This work focuses on the development of an efficient CFD model for flotation columns. The bubble size distribution in the column has been modelled using the Population Balance Equation (PBE), which is solved using the Direct Quadrature Method of Moments (DQMOM). Coupled with the PBE, the multiphase flow equations in the column have been modelled using the standard Eulerian–Eulerian approach. The solution of this coupled system has been made tractable in this work with the implementation of a highly parallelised adaptive-mesh finite element method. This powerful framework has been implemented in the open source CFD code Fluidity and it allows the carrying out of detailed simulations of flotation columns in 2D and 3D, with important implications for industrial column evaluation and design."

Jan 1, 2016

By L. G. Smith, C. A. Shook, W. H. W. Husband, W. Schriek

"The flow of slurries in pipelines is governed by many variables, and the study of the influence of each of these variables is difficult, if not impossible, in some cases. Many correlations are available which fit data within a given range. However, no one method is yet available to design a slurry pipeline for all desired conditions without at least some physical measurements on the slurry itself. For this reason, the slurry pipeline facilities at the Saskatchewan Research Council have been developed during the past 12 years and it is hoped that the development will continue until the process is thoroughly understood and test facilities are no longer necessary. This paper outlines methods currently used and under development at the Saskatchewan Research Council for measurement, control and study of the variables governing the flow of slurries."

Jan 1, 1973

By A. Fischersworring-Bunk

The new inline six spark-ignition engine is the realization of BMW's concept of efficient dynamics at high technological level to achieve the attributes of low weight and high efficiency, The paper presents different aspects of the development and manufacturing of BMW's inline six-cylinder engine magnesium-aluminium composite crankcase, Reference will be made on the AJ magnesium alloy optimization approach to balance between mechanical properties and the high pressure die cast ability requirements, Next to this aspect some mechanical design issues will be covered, with CAE methods playing an instrumental role in the early project stage for the assessment of the compound concept, Due to the compound design chosen, the interface posed challenges to both design and productions, A set of novel techniques has been used to cope with these tasks.

Jan 1, 2006

By W. R. Tyson

Imperfections such as lack-of-fusion and undercut are inevitable in field welding of pipelines. Above a certain size, such defects must be removed or repaired. In the present state of the art, determination of allowable defect size is done by Engineering Critical Assessment (ECA). This requires measurement of toughness, and comparison of toughness with crack driving force. ECA methods used in current international pipeline standards will be reviewed and compared.

Jan 1, 2010

By F. Charette

The paper reviews the requirements of the instrumentation required to monitor mining excavations in a high stress environment, and the development plan to instrument the D-Bolt in such a fashion as to be able to follow the behaviour of the bolts in relationship to the ground movements and support performance. Recent field observations of D-Bolts under static and dynamic conditions are also presented. Also discussed is the assumed mechanical behaviour of the D-Bolt. D-Bolts are used in two (2) Canadian underground mines operating in high stress environments and tested in three (3) other operations.

Jun 1, 2012

By M. P. Brameld, G. Archambault, R. H. McCorkell

"The rates. J. at which materials emit radon are of interest in studies of the sources of radon in mines. buildings. soils overburden and other places where it may indicate the location of ore or be a health hazard. Here J values were determined by measuring the radon concentrations by means of scintillation counters or alpha-particle track detectors in chambers in which specimens were sealed. Errors in the measurements due to leakage from the chambers. lack of secular equilibrium in the decay series of the radon measured, or the limited rate of diffusion of radon from powders or within the chambers were shown to be insignificant or could be corrected. Scintillation counter measurements are highly reproducible; track detector measurements also appear useable and may be made on many small samples using small, simple chambers. J measurements were made for uranium ores, drill cores, standard CANMET pulps. concrete and gypsum board. Powdering of ores had little effect on their J values.IntroductionIn the mining and mineral sciences, radon (222Rn) is of interest chiefly for two reasons: in geochemical exploration for mineral deposits its presence in soil. overburden and water in more than background concentrations may indicate the existence and locations of uranium deposits and, if present in sufficient concentrations, it is a possible health hazard in mines, mills and other places where people live and work. The latter aspect of radon's role has received considerable attention recently(1,2,3,4,5), and surveys of soil-gas radon concentrations have been used for some time in searches for uranium deposits(6,7,8,9,)."

Jan 1, 1981

By A. Navarra, Norman Toro, T. Marín, Fernando Ayala

The quantitative techniques to evaluate the enhancement of a particular unit operation should consider the corresponding changes to the adjacent unit operations. For example, the expansion of off gas handling capacity should consider the corresponding changes in converter cycle times, matte grade, and other operational parameters, that can provide the optimal system-wide benefit. In general, the upgrading of smelter equipment is risky due to the size of capital investment, as well as any unforeseen impacts on rest of the operations. However, this risk can be mitigated by applying the principles of Front End Loading (FEL) in the formulation of multiphase re-engineering projects. The initial phases of engineering are relatively inexpensive, and determine whether or not to pursue the subsequent phases that are comparatively more expensive. Each phase of engineering depends on increasingly detailed descriptions regarding the critical phenomena that can effect design decisions; the increasing levels of detail may result from numerical simulations, as well as laboratory and plant trials. The quantitative framework should be sufficiently flexible to accommodate these increasing levels of detail, regardless of the particular phenomena, so that it may evolve throughout the project. The current article describes the combined usage of mass balancing, thermochemistry and multiphysics, in the development of discrete event simulation (DES) and finite differences (FD). The incorporation of finite differences into a DES framework depends on adaptive time-stepping, to determine threshold-crossing times, e.g. when the matte temperature surpasses a critical level that necessitates the addition of cold charge. The hybridization of DES and FD is appropriate for multiphase smelter development projects, as it supports semi-continuous material flows, operational policies and scheduling, as well as unexpected events and trends, in increasing levels of detail. This type of framework will support the installation and tuning of modern control systems, including state-of-the art sensors and machine learning algorithms.

Jan 1, 2019

By A. A. Rogozhin, E. G. Likhnikevich, S. I. Anufrieva, A. V. Kurkov

The Beloziminskoe deposit in Siberia is a large, potentially productive deposit of rare metals contained in ochreous apatite pyrochlore ores formed by weathering of a carbonatite. The ores are composed of pyrochlore, columbitized pyrochlore, monazite, apatite, magnetite, ferric and manganese hydroxide, titanic iron ore, zircon, hydromica, quartz, feldspar, and carbonates. A gravity-flotation enrichment flowsheet with application of cationic and anionic collectors has been developed. This flowsheet allows for obtaining a pyrochlore concentrate containing 44.3% Nb2O5 and 1.89% P2O5 with recovery of 55.83% Nb2O5 as well as an apatite concentrate containing 39.2% P2O5 and 1.05% TR2O3 with recovery of 62% P2O5 and 43.23% TR2O3 from ores containing 0.92% Nb2O5, 16.9% P2O5 and 0.6% TR2O3. Rare-earth concentrate containing 40% TR2O3 with recovery of approximately 10% TR2O3 was obtained at the same time. Major losses of valuable elements are related to slimes, which make up more than 50% of the ground ore. The niobium concentrate does not meet the phosphorus and radionuclide concentrations needed for the production of ferro-niobium. Acid leaching and sulfatization provided a high level of phosphorous and radionuclide removal. Conditions include hydrochloric acid pre-leaching at 75- 80°C with an 18% HCl solution for four hours and low-temperature sulfatization of acid-leached concentrate at 160-180°C for one hour followed by water leaching of the residue. The apatite concentrate could potentially be processed using nitric acid leaching. This technology is based on decomposition of apatite concentrate with 55-57% strength nitric acid with transfer of rare-earth metals into solution in the form of ammonium phosphate. This technology recovers a rare-earth concentrate containing 95% TR2O3 with extraction of 86%, and highly concentrated polynutrient fertilizer (ammophos) with phosphorus extraction of 95%. The completed research shows how complex multicomponent ores of residual soil may be processed for the extraction of niobium, phosphorus, and rare-earth products.

Jan 1, 2016