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By Pierre Montrueil, Marcel St-Amant

Within the next few years, underground mobile equipment will be partially automated. Mining methods will integrate more and more automation. Such an evolution will be possible only if adequate underground communication systems are developed. This is expected due to the available competence in Canadian telecommunication, to the economic pressure on the Canadian mining industries for international competitiveness and to the social changes where a better working environment (i.e. less accidents) becomes a major concern. CCARM propose the concept of a Production Area Network for Automated Mobile Units called PANAMU as an intermediate size communication system. It can be implemented using mature present-day technology and it can be integrated in some mine wide communication systems. It can evolve so as to incorporate new technologies because of its modular concepts. In this paper, the communication requirements are estimated, the amtmptions are defined, the concepts of the PANAMU are presented and an over- view of its implementation is described. CCARM presents this article to the mining industry as a document for discussion.

Jan 1, 1994

By P. Coulombe, J-F. Riverin, A. Gaboury

Cavity cleaning during anode change generates a material that consists of anode cover material and cryolite melts. This material is scooped and placed in bins for transport and further processing and recycling as fresh anode cover material. Typical processing methods in use involve cooling of the hot cavity bath in bins, with or without emission treatment systems, until it is adequate to be processed and grinded to the required particle size distribution. Handling of the hot and cooled cavity bath material can be labour intensive. It also generates significant air emissions which contain particulate and gaseous fluorides. With the advent of the Aluminerie Alouette smelter Phase II expansion, the hot cavity bath tonnage to be processed increased to 700 t/day and maintaining existing practices was not satisfactory. This article presents a novel process implemented at the Alouette smelter where cavity bath is processed as a hot material directly from the potlines ( 600-800°C range), sized, cooled and then processed in the existing cold bath treatment plant. The system is designed to process 36 t/h, is fully automated and requires limited monitoring from operations. Implementing this new system in a Browrifield environment imposed numerous constraints for space, interfaces with existing operations, commissioning and ramp-up. It is presently operating at approximately 80% availability and is easily meeting the requirements of the potlines. This system has significantly improved the workplace environment in the bath treatment area and reduced the overall particulate and gaseous fluorides emissions at Alouette. Aluminium 2006 45th Annual Conference of Metallurgists ofCIM Montreal, Quebec, Canada Edited by

Jan 1, 2006

By Alan L. Sangster

Auriferous, bedding-parallel veins occur in zones of carbonaceous, argillaceous and sulfidic turbidites in the Lower to Middle Cambrian sandy flysch of the Goldenville Formation. The 0348 values for vein and wall-rock arsenopyrite and pyrrhotite, and for regional pyrite and pyrrhotite, are highly positive. The values are similar to those from Cambro-Ordovician sediment-hosted deposits of other types, and display trends that increase upward in the stratigraphic sequence. The similarity in composition of vein and wallrock sulfides indicates a seawater-sulfate sourCe for sulfur, derived from the enclosing rocks at the time of vein formation. The upward increase in ?34S values is consistent with closed system sulfate reduction in the anoxic portion of a stratified water-colurnn. Published ? 13C and ? 18() values for Meguma Group vein carbonates are unlike those of other gold-vein carbonates, but are similar to those of diagenetic-metamorphic carbonates from the Meguma Group and elsewhere. These data indicate that the source for the vein-related sulfides and carbonates may be the host strata; possibly the arsenic and gold were derived from the same source.

Jan 1, 1992

By R. Abel

During the last eight years, the Ventanas electrolytic refinery has been improving its results by applying a series of new operational practices, such as the reduction of electrode spacing from 115 mm to 105 mm., raising the current density to 305 A/m2, modification in the operators shifts to about 70% of the workers, reducing the pulling cycles by two hours, and the erection of a new anode preparation machine. These improvements allowed an increase in the refinery capacity from 323,000 to 382,000 metric tons of electrolytic copper per year. In the same period it has obtained certification under the ISO 9001:2000 and ISO 14001:2004 standards. All of these developments have been achieved using conventional technology with copper starting sheets. The continuous improvement that is covered in this paper has allowed Ventanas to optimize its production, costs, and operational results. For the next years, it is planned to follow the same tendency, bringing the productivity of the plant to higher levels.

Jan 1, 2007

By Chaluvadi K. Sridhar, Prashanta K. Chatterjee

"IntroductionThe planning of an underground coal mine requires a complex blend of technical expertise, experience and subjective design criteria implemented by the mining engineer. Currently the procedure is largely manual and requires considerable resources to generate a single mine plan. Often three or four people are assigned to work in the development of a single draft layout. Evaluation of the layouts is also tedious as it requires many repetitive calculations. The evaluation of layouts developed manually generally attempts to derive a single economically feasible solution. Operational constraints in underground coal mining such as manpower, time, equipment, etc., do not allow the generations of more than one alternative layout. As a result, the first plan is generally the only one considered.Computer-aided mine planning can automate many of the manual procedures and calculations involved in mine planning thus allowing to evaluate man y layouts and mining strategies and to select the optimum plan with confidence. An optimized planning procedure will also provide the capability to evaluate mine performance continuously and critically, thereby helping to maximize return on investment. Although recent advances in computer graphics have provided the hardware necessary for developing and evaluating min e plans rapidly, software that will allow the mining engineer to make use of the new technology is slow in developing. The need for such software packages has been recognized and ackowledged.At several sessions in recent conferences on the applications of computers in the mining industry, the use and benefit s of computer-aided mine planning were discussed. However, there were few papers presented that referred to actual applications of interactive graphics to underground mine planning. The emphasis of this study is toward the development of a completely integrated computer-aided underground mine planning package that integrates geological modeling, engineering design and planning"

Jan 1, 1986

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 F. Kapeller, G. Herget

"The need for monitoring the effect of changes in ground stresses due to mining in hard rock has existed for many years. The Mining Research Laboratories of CANMET, EMR have developed a new tool which monitors with high precision the radial deformation in boreholes. The result is the Mining Research Laboratories strain monitoring system (MSMS) which uses the highly stable and very sensitive vibrating wire principle to monitor deformations in relatively large boreholes, e.g. 76 mm to 153 mm diameter.The vibrating wire is strung across a relatively large proving ring and operates at a frequency between 600 to 1800 Hz. The read-out system is based on continuous vibration.The ring is installed with a hydraulic tool and brought into contact with the surrounding rock through precisely machined and guided wedges. The resolution of the system is in the neighbourhood of 4 x 10-4 min/ Hz. The data collection can be carried out with a portable read-out unit and provisions are available for automatic data collection. Stresses may be calculated from strain readings.The system was tested in cooperation with the Centre de recherches minérales at the Niobec Mine in Quebec for the purpose of monitoring the effects of drill drift development and slope mining on surrounding ground stresses.After access was available to the site, 153 mm diameter holes were drilled for the determination of in situ ground stresses. These holes were then used to install the strain monitoring system. The effect of drill drift development and production blasting in stopes C-203-13 and C-203-15 on ground stress distribution could be observed clearly.The horizontal relaxation in the core of a pillar which occurred during mining of adjacent rooms was between 0.082 mm to 0.111 mm. Calculations of stresses from these deformations indicate that the rock material is still in an elastic condition.Roctest of Montreal has obtained a license on the manufacturing and distribution rights. A patent has been registered and CANMET will assist in installation of the MRL strain monitoring system and the interpretation of records."

Jan 1, 1989

By V. L. Mitsopoulos

This paper provides a summary of tailings disposal techniques and the improvements that have been made through the introduction of thickened tailings disposal. The general properties and characteristics of thickened tailings are described, as is a design process for selecting appropriate technologies for thickening, pumping, transporting and storing tailings. The factors affecting the selection of an appropriate disposal site and operational considerations for the effective utilisation of tailings storage areas are also documented.

Jan 1, 2006

By M. D. Quinn

THE sand and gravel used for backfilling at the Hollinger mine is obtained from deposits in a low range of hills some three miles north of the mine, where the Company owns a number of claims. The material is transported to the mine by aerial tram. Shipments from these deposits to the Hollinger mine commenced in June, 1927, and since May, 1936, sand has been supplied also to the McIntyre mine. During 1942, Hollinger requirements were 1,700 tons per day, and 900 tons per day was delivered to McIntyre. For the past seven years production has averaged 900,000 tons annually, and total deliveries to the end of 1942 were 13,129,022 tons, of which 11,075,339 tons went to Hollinger and 2,053,683 tons to McIntyre. Some years ago, when the original pit was approaching exhaustion, new workings were opened on claims east and south of the tramway terminal. It soon became apparent that the sand varies considerably in character from place to place. The weight per cubic foot was found to range from 85 to 130 lb., and the water percolation rate from 2 to 50 inches per hour. As the mine requirement is a sand with percolation rate of 6 inches or better per hour, it was evident that in certain parts of the deposits the material was not suitable for use as backfill. As a consequence, it was decided to carry out a programme of systematic sampling of the claims in order to select the areas containing suitable material for back-fill and at the same time estimate the tonnage available.

Jan 1, 1944

By M. L. Free

Laboratory scale extraction of metals from heterogeneous materials such as copper ores is often performed using fine material to increase kinetics and reduce sample size requirements and costs. In contrast, commercial extraction is usually accomplished using much larger material sizes than are used in laboratory settings. The large size difference between laboratory testing and commercial application materials makes it difficult to use laboratory test data to accurately predict performance for commercial material. One solution adopted widely in industry is the use of large test columns. Large test columns cost considerably more to set up and run and take much longer periods of time to evaluate than laboratory scale tests with small particles. Consequently, from a cost and data collection efficiency perspective, the development of accurate scale up methods offers significant potential for saving both time and money. This paper provides details for a new approach to correct for scale-up phenomena in heterogeneous material processing.

Jan 1, 2007

By Michel Dagbert, Mohammed Harfi

"Abstract - The Draa Sfar polymetallic deposit, at about 16 km NW of Marrakech in Morocco, is a massive sulfide zone at the contact between an underlying volcanic and an overlying clastics sequence. The mineralized body is a flat lens with schistosity and "boudinage," tilted to the west and with a strong dip to the east. The lens extends over a strike length of about 2 km and from surface to a depth of about 1 km, with thickness varying from 1 m to almost 30 m. It has been intersected by about one hundred surface drill holes and, in its south part, by about thirty underground fan holes from two exploration levels at depths of 300 m and 400 m. On these two levels, the massive sulfide zone has been channel sampled over a cumulative length of about 0.7 km. Results from drill and channel samples are used to estimate the resources of the orebody according to several methods: sections, polygons around intercepts on a longitudinal plan, grids on the same longitudinal plan with various distance weighting methods including kriging and, finally, a 3D grid with the same range of interpolators. A comparison of the various estimates delineates the important factors in deriving resources for this type of deposit. Those factors are mostly geological and related to the interpretation of the geometry of the two limiting surfaces of the zone. For the 3D gridding, the authors have devised a new and original method that constrains the interpolation of blocks from samples to a geometry of limiting surfaces. The resulting model shows internal grade variations that parallel fluctuations of zone thickness and orientation without having to re-orientate the search window in each block. Résumé - Le gisement polymétallique de Draa Sfar, situé à environ 16 km au NW de Marrakech est un horizon de sulfure massif au contact d’une formation volcano-sédimentaire de base et d’une formation détritique sur-jacente. Le corps minéralisé se présente sous forme d’une méga-lentille aplatie, schistosée, boudinée et déversée vers l’ouest avec un fort pendage vers l’est s’étendant sur une longueur de 2 km et une profondeur de près de 1 km avec une épaisseur variant de moins d’un mètre à près de 30 m. Il a été reconnu par plus d’une centaine de sondages de surface et, dans sa partie sud, par une trentaine de trous souterrains en éventail à partir de deux niveaux à des profondeurs respectives de 300 m et 400 m. Sur ces mêmes niveaux, des traçages ont permis de rainurer le minerai sur une longueur cumulée de 0.7 km. Les données de sondage et de rainurage ont servi à estimer les ressources du gisement selon plusieurs méthodes : sections, polygones sur longitudinale, grille sur longitudinale avec différentes pondérations en fonction des distances incluant le krigeage et enfin grille tridimensionnelle avec le même éventail de pondérateurs. La comparaison des estimés obtenus permet de mettre en évidence les facteurs importants dans l’estimation des ressources de ce type de gisement. Ces facteurs sont essentiellement géologiques et relatifs à l’interprétation de la géométrie des limites des corps minéralisés. Pour l’estimation sur grille tridimensionnelle, on a mis au point une technique originale qui calque l’interpolation des blocs à partir des échantillons sur cette géométrie des surfaces de contact. Le modèle résultant montre des variations internes de teneurs qui épousent les fluctuations d’épaisseur et d’orientation de la zone sans qu’il soit nécessaire de ré-orienter les fenêtres de recherche dans chaque bloc."

Jan 1, 2002

By Alan L. Sangster

Abstract -Auriferous, bedding-parallel veins occur in zones of carbonaceous, argillaceous and sulfidic turbidites in the Lower to Middle Cambrian sandy flysch of the Goldenville Formation. The ?34S values for vein and wall-rock arsenopyrite and pyrrhotite, and for regional pyrite and pyrrhotite, are highly positive. The values are similar to those from Cambro-Ordovician sediment-hosted deposits of other types, and display trends that increase upward in the stratigraphic sequence. The similarity in composition of vein and wallrock sulfides indicates a seawater-sulfate source for sulfur, derived from the enclosing rocks at the time of vein formation. The upward increase in ?34S values is consistent with closed system sulfate reduction in the anoxic portion of a stratified water-column. Published ?18C and ?18O values for Meguma Group vein carbonates are unlike those of other gold-vein carbonates, but are similar to those of diagenetic-metamorphic carbonates from the Meguma Group and elsewhere. These data indicate that the source for the vein-related sulfides and carbonates may be the host strata; possibly the arsenic and gold were derived from the same source.

Jan 1, 1992

By R. C. Wallace

Since the time when Canada's East and West were joined by the railway, and communication was established into the interior, settlements grew on the southern fringe of the great Precambrian area that formed the northern protaxis of the continent during its vicissitudes of growth. They clung precariously to the fringe of that ancient land, for the Precambrian is not generous to those who wish to live by the fruits of the soil, except in those limited areas where the Pleistocene ice-sheet has been profuse in its gifts of clay to cover the hard surface of the Precambrian rock. Later settlements spread westwards over the expanse of Cretacean plains that now form the wheatfields of the Canadian West; but there still remained in northern and western Ontario, in eastern and northern Manitoba, a pioneer race, to whom agriculture had attractions only in so far that it provided the wherewithal to lay siege to the riches of the Precambrian. And they had a vision beyond their time. More than they knew, they had seized the fact that for the complete rounding out of Canadian national life, a8 well as for the establishing of the necessary contributions towards the economic stability of Canada and its provinces, an industry in mining sh01.dd be well and truly built in the hinterland of the central provinces. Failing the winning of mineral from the rocks, and timber from the forests, there would remain between the East and the West an enormous barrier of unproductive country which would not only be an incubus to the agricultural people in their struggle for economic liberty, but would effectively, and for all time, remain an un-populated void across which the aspirations of East and West would be unable to unite.

Jan 1, 1924

By Rashid Bashir

The presence of groundwater in the form of large aquifers can have an important influence on investment decisions for underground mines. The design for such mines requires development of special mining methods, and mine dewatering infrastructure to avoid hazards during shaft sinking and underground development. The costs associated with mine drainage control and Mine Dewatering Systems (MDS) are relatively small compared to the huge consequential losses that can occur in case of an uncontrolled inflow and subsequent flooding of the mine. The design of MDS needs consideration of accurate prediction of the maximum uncontrolled inflow rate, availability of the system during an uncontrolled inflow while the inflow is mitigated, and decision on pumping system technology to have capability to operate under water. The research presented in this paper provides a theoretical framework for a reliability based design procedure which takes into account the uncertainty in the estimate of the maximum uncontrolled inflow, performance of the system during the period of an uncontrolled inflow and a methodology to decide on appropriate pumping technology considering the reliability of the system and available underground storage. The reliability based mine design procedure integrates the ideas of Effective Reserve and Hydraulic Reliability Index to come up with a unified methodology for design of Mine Dewatering Systems.

Aug 1, 2010

By K. Nagai

The Asian projects are now in their second terms after the five-year first terms. Ultrafined-grained steels were developed in lab-scale and/or in practical process. Basic approach has been performed to explore the evolution mechanisms of ultrafine-grained microstructures. There have been investigated two approaches to make the ultrafine grains: the "recrystallization route" and the transformation route. In the "recrystallization" route, heavy deformation at low temperature is necessary for the ultra-refinement. In the transformation route, making the high density of ferrite initiation sites in the deformed austenite, especially of the heavily compressed austenite structures, is essential for the ultra-refinement, and further hindering the ferrite growth is also inevitable to utilize the high initiation rate. Strength and toughness are dramatically improved by the ultra-refinement. Fatigue property is also excellent. The poor uniform elongation can be enhanced by the design of the second phase dispersion. At the same time the application has been also pursued from various viewpoints of engineering to take advantages of the ultrafine-grained steels. Bridge, ship, construction, automobile and other high strength parts are being attempted for the application.

Jan 1, 2004

By Fidelis T. Suorineni

The conditions for rockburst occurrence are traditionally identified as: high stress, high extraction ratio, strong brittle rocks, folding, faulting, and unfavourable excavation geometry. Based on a critical review of case histories, this paper identifies oblique loading of orebodies by the major far field principal stress as a cause of rockbursts. Orebodies subjected to this loading condition are termed orebodies in shear. Orebodies in shear are subjected to compressive and shear loads. The case histories presented unambiguously show that the magnitudes of the far field principal stress alone, and a knowledge of the conventional rockburst causing factors are not sufficient for mine planning and design. The orientation of the major far field principal stress, or for that matter the driving stress relative to the orebody axis, should be recognised as one of the causes of rockbursts. It is suggested that since stress orientation is an important factor, and orientations from stress measurements are so variable, orientations from stress measurement data be complemented with underground observations from borehole and excavation breakouts to determine the actual in situ stress orientation, whenever possible. Also stress modelling for the design of critical elements (pillars) should include a sensitivity analysis on the relative critical field stress direction. The paper emphasises that special attention should be paid to or

Jun 1, 2012

By J. D. Jones

The geographic occurrence of economic mineral deposits presents a variety of problems in modern tailings disposal operations. This paper presents case histories in several sectors of the mineral industry as well as the several stages of operations planning required for new designs, system expansion, reactivation of abandoned systems and upgrading to present environmental standards.

Jan 1, 1978

By Y. Hou, E. Arinaitwe, L. Tong

A series of dense medium separation (DMS) tests were performed on four low-grade copper ores from Mount Polley mine in order to determine their amenability to pre-concentration. The tested ores contained disseminated sulphides, mostly chalcopyrite with low copper grades (0.15% - 0.2%) and relatively high iron grades (4.76% - 5.63%). The samples were screened into different size fractions ranging from 9.5 mm to 50.8 mm and DMS tests were performed on each size fraction at various separation densities. The pre-concentration efficiency at different size fractions and separation densities was evaluated in terms of metal upgrading and distribution. Mineralogical tests were also performed on selected DMS sink and float samples in order to understand the influence of mineralogy on the pre-concentration efficiency. The results showed that significant copper upgrading was achieved for intermediate size fractions only at the highest separation density tested. The copper recoveries generally increased with particle size at all separation densities. However, it was impossible to upgrade the copper content in the ores and achieve acceptable recoveries and mass rejections at the same time. Copper recoveries and grades showed a strong correlation with iron recoveries and grades indicating that it is possible to pre-concentrate copper by recovering magnetite and other iron-containing minerals in the ore. Overall, the results suggest that the optimum separation density and pre-concentration efficiency is a function of particle size, and that the ore mineralization properties limit the performance of DMS as a pre-concentration technology for such low-grade disseminated ores.

Jan 1, 2014

By M. Ye. Shulgina, M. L. Bolotin, S. A. Prokopev, Ye. S. Prokopev

Iron ores concentration at Russia’s operations is carried out using conventional flow sheets. They comprise the two-four stage grinding followed by one-two stage magnetic separation. This results in the maximum recovery of magnetite to concentrate and the tailings generation. The final concentrate is generated only during the last stage of magnetic separation. Technologically, this flow sheet layout is not effective at recovering the liberated magnetite grains during grinding to the resulting concentrate. Advanced models of magnetic separators do not allow for the selective separation of the tailings and the portion of the resulting iron ore concentrate. Magnetic product which is the ore mixture of the liberated magnetite grains, high grade and low grade intergrowths is directed to the next grinding stage. In this case, regrinding of the liberated magnetite occurs. In addition, the performance of hydrocyclones during classification in closed grinding circuits is poor. Their classification efficiency does not provide the material separation in accordance with the size. In this case, simultaneous separation in accordance with the density occurs. The quartz particles with the size of 300 mm have similar velocity and trajectory like the particles of magnetite with the size of 60 mm. As a result, light and coarser intergrowths report to the overflow and free heavy magnetite grains report to underflow and return to regrinding (“the density effect”). This resulted in a significant increase of a mill circulating load, the decrease in the feed throughput and higher power consumption. In this connection, the development of iron ore concentrate stage recovery with the focus on gradual liberation of the intergrowths is getting much attention. Gravity concentration technique, particularly, spiral separation is effective at solving the problem of stage recovery not only the dump waste product but also high grade magnetite concentrates at the early concentration stages. This can be attributed to a significant difference in magnetite (4.9-5.2 g/cm3) and host minerals (quartz 2.7 g/cm3) densities, which is the principal during gravity concentration. The test work on concentration of various products samples from current operations (the mills discharges, concentrates from various stages of wet magnetic separation and cyclones underflows) was carried out. Spiral separators SV- 500 and ShV-500 manufactured by Spirit LLC were used for the test work. High grade iron ore concentrate (69.05% Fe) was generated during primary wet magnetic separation concentrate concentration using a spiral separator. During the concentration of mills discharges the content of iron in the resulting concentrates and middlings of wet magnetic separation II stage was 64.5% and 64.6%, respectively. The recovery of iron to the concentrates of spiral separation was 33.6-42.0%. The studies presented demonstrate that by using spiral separation for iron-bearing ores concentration, you can separate magnetite liberated grains at the early concentration stages, decrease their regrinding and circulating loads in grinding circuits. This process is able to improve the overall recovery and economics of iron ores concentration process.

Jan 1, 2016

By S. Huang, K. Xia

"During crushing, rock particle is subjected to complicated loading and the particle shape influences the fragmentation outcome. Thus, a highly controlled laboratory test is desired to establish the relation between the loading and the fragmentation parameters for better understanding the rock crushing mechanism. In this work, a split Hopkinson pressure bar system in combination with high speed cameras is utilized to carry out a dynamic ball compression test, in which the spherical rock sample is adopted to avoid the shape effect. Using the elasticity theory, the history of the axial symmetric tensile stress perpendicular to the diametrical direction along the loading axis is determined, from which the loading rate and the dynamic indirect tensile strength are calculated. With the aid of the moment-trap technique, the total energy absorbed by samples is accurately determined from the one-dimensional wave analysis. Furthermore by considering the kinetic energy of the sample fragments using the high speed camera snapshots, the surface energy is determined for each sample. The relations between the loading rate and the fragmentation parameters, i.e., the number of fragments and the surface energy are established. The application of this method to a granitic rock shows that it is flexible and can be applied to the crushing study of generic brittle solids. INTRODUCTIONCrushers are widely used to break rocks to extract specific minerals in the mining industry, and to obtain rock fragments with desired size distribution in construction industry. During crushing, the breakage of particles can be in either the single-layer mode or the multi-layer mode. In the single-layer mode, the particle breakage can be assumed to be isolated, in which the interaction between particles can be ignored. It is thus suggested by many researchers that highly controlled single particle test should be performed to establish the relation between the input mechanical energy and size reduction for better understanding the crushing mechanism (Yashima et al., 1987; Tavares, 2007; Pitchumani et al., 2004)."

Jan 1, 2015