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By G. J. Reid, D. H. Stewart

"A diversity of structures and rock types in the Aft on pit has resulted in the occurrence of several different types of wall failure. Delivery of ore to the mill has not been affected and safety has not been compromised thanks to effective remedial 1V0rk and to a system of structural mapping, back analyses of failures, groundwater monitoring, and simple movement monitoring. Remedial measures have included artificial support, dewatering (including vacuum-assisted drainage), flattening of slopes and temporary buttressing. This paper describes six different wall failures at Afton and highlights the features of each. Examples given include rates of movement, extent and direction of movement, and piezometric responses. The practical, low-cost monitoring system was sufficient in one case to allow the prediction of date of failure. IntroductionThe Afton copper deposit is located 13 km west of Karnloops, British Columbia and has been mined for nine years out o f an expected eleven-year life. Open pit mining has reached 700 feet below sur face and is designed to proceed to 970 feet below surface by the time the pit is completed. The excavation is in a structurally and lithologically complex environment. Inevitably, some wall failures have occurred but these have been limited to small, manageable failures which have not compromised production or safety. To handle the failures it has been necessary to understand their nature. Of prim e concern has been the rate s of movement, but displacement vectors and hydrology have been monitored as well. The monitoring system is based on EDM surveys and on wire extensometers and plates set across cracks. Water levels have been read in standpipe piezometers. At Afton the emphasis has been on simple, practical, and inexpensive monitoring and because rock type s and structures play such a major role in any failure, detailed geologic al mapping is carried out."

Jan 1, 1988

By C. E. McCoy

This paper will discuss briefly loader shovel requirements and then present a detailed survey of electrical drive systems to meet these requirements. The survey in general will deal with the various electrical provisions for shovel drives, along with the advantages and disadvantages, and in particular will discuss the MG set and static D. C. drive systems. Also included will be some insight into the requirements for optimum electrical power at the shovels.

Jan 1, 1979

By S. I. Vobnout, J. Wm. White, J. P. Olson

"Mine management now recognizes the value of computer-based truck-shovel dispatching in open pit mines. The key tangible benefits are substantial productivity increases with a given fleet of equipment or, alternately, significant reductions in equipment required to meet production quotas. In this paper, the authors review the literature, report on efficient, optimal algorithms for haul truck dispatching in real-time, and briefly discuss methods used by various mines to evaluate productivity improvements over manual methods. Actual results obtained at thirteen mining operations around the world are also presented.IntroductionModular Mining Systems manufactures, installs, and supports its computer-based DISPATCH system at mines worldwide. DISPATCH is a large scale, computer-based mine management system which controls the dispatching of all haul trucks in any open pit mine (Fig. 1). When increased production is important, DISPATCH gets the needed production increase with fewer new or recommissioned trucks. DISPATCH also helps operations meet its blending objectives while minimizing rehandle and maintaining production. Furthermore, DISPATCH includes a powerful, eventdriven simulation subsystem. With the simulator mine management can pose ""what if' situations and see the predicted effect on production"

Jan 1, 1993

By J. L. Barton, R. A. Murray

"This paper looks at how Syncrude Canada Ltd. is utilizing the Conveyor Belt Monitoring technology developed and patented by the Australian CSIRO and licensed to Syncrude by Conveyor Belt Monitoring of North America, Inc. The technology involves magnetizing the steel cables in the conveyor belts and detecting the fields produced by breaks, gaps or cable ends using special sensors which feed the signals into a multi- channel recorder to provide permanent traces of the various events taking place in the steel cable belts.The data is analyzed and combined with existing belt audit programs, to assist in predicting belt life, change-out criteria and belt design, belt loading and construction. All of these applications of the CBM technology leads to better utilization of resources and forms an integral part of the conveying system reliability program."

Jan 1, 1992

By Gonzalo Mato, Colin Godwin, G. Ditson

"The mid-Cretaceous Seagull batholith intruded Mississippian sedimentary and volcanic rocks and Jurassic(?) granitic and ultramafic rocks within the Omineca Crystalline Belt in the Yuk on Territory near the British Columbia boundary. Leucoerotic fluorine- and boron-rich granites of the batholith exhibit many textural variations from aplite to pegmatite, but are dominated by a coarse-grained seriate unit and a fine-grained porphyritic unit.Four distinctive tin vein occurrences within and near the batholith are described, the most interesting of which is the MC showing of quartz-calcite-chlorite-cassiterite veins in intensely fractured zones of sedimentary and volcanic rocks. Three other showings occur within the batholith:J) the EC showing of quartz-fluorite-cassiterite-sulphide veins with prominent muscovite-illite alteration;2) the DU showing of quartz-hematite-fluorite-sulphide- sulphide-cassiterite with considerable manganese staining and sericitic alteration; and3) the VAL showing of quartz-tourmaline-cassiterite-fluorite-arsenopyrite veins with little associated alteration.Most cassiterite occurrences are within easterly-trending, vertical structures and all occurrences are thought to represent parts of a single system. These mineralogical and physical variations are apparently related to the distance from the upper contact of the batholith.For the Seagull batholith, Rb-Sr isotopic data give a 100±1.4 Ma isochron age that is concordant with the K-Ar model age from biotite of 101±4 Ma. Initial Sr isotopic ratios for the batholith are high at 0.712, indicating an old, sialic crustal source for this pluton. This initial ratio is similar to values for granitic rocks associated with tungsten deposits in the Yukon Territory. The high initial ratio for Sr, the high Si02 content, the high s/I index, the presence of normative corundum. leucogranitic composition and associated lithophile-tungsten mineralization demonstrate that the Seagull batholith is probably an S-type granitic body. This factor is significant to regional exploration jar tin and tungsten in the Canadian Cordillera."

Jan 1, 1983

By G. E. Norman, R. E. Michelutti

"One of the major objectives of Falconbridge has been and continues to be, to minimize the impact of its operations on the environment around its Sudbury operations.The approach to achieving this objective and the results, are discussed under the following topics .I . Sulphur Dioxide Emission Improvements.2. Effluent Treatment Improvements .3. Effect of the Envrionmental Improvements.Sulphur Dioxide Emission ImprovementsHistoryThe rejection of pyrrhotite in the concentrators is one method of reducing the amount of sulphur to the smelter and therefore the sulphur dioxide emissions. In the 1950s and 1960s, Falconbridge developed the capability to remove 54% of this pyrrhotite. Numerous attempts were made to increase this amount by treating the pyrrhotite for recovery of nickel and in some cases elemental sulphur. Processes tested and operated were: hydrometallurgical pilot plant, roast-leach commercial operation and nickel-iron refinery. None of these processes proved to be commerically successful for both technical and economic reasons. Falconbridge therefore redirected its efforts to reducing sulphur emissions by improving its smelting process under The Smelter Environmental Improvement Project. A major component of this project was the installation of a sulphuric acid plant to recover the S02 in the roaster off-gases."

Jan 1, 1984

By Gene O. Cowie

"Zinc, which once enjoyed an unchallenged position in the field of decorative applications, has lost a substantial share of its markets to other materials, particularly plastics. This turn of events has led the zinc industry to explore new market areas, particularly those applications where the engineering properties of zinc can be utilized. This paper gives an overview of the zinc industry's efforts to develop the data base and product development technology which have enabled zinc alloys to emerge as engineering materials. It also indicates those areas in which the research facilities of the zinc industry must be employed to ensure that zinc alloys keep pace with developments in competitive materials and processes.The Materials RevolutionThe development and utilization of new materials and manufacturing processes progressed for centuries by evolution. Recently it erupted into a revolution, which may become as significant as the industrial revolution. The materials revolution has impacted upon many industries, but none has been affected more traumatically than the North American automotive industry. The plight of that industry is of great importance to us because their problems have, to a great degree, become problems to the zinc industry.Much of the impetus behind the automotive trauma came from the battery of motor vehicle regulations promulgated by the United States government in the 1970s. These regulations required that the efficiency of passenger cars, in terms of miles per gallon, be approximately doubled in ten years. In view of the fact that major changes in the automotive world require three years of lead time to implement, the industry was left with only seven years to perform the task. The automotive industry was simultaneously required to make progress in other areas, such as reduced emissions, reduced cost of repairs and increased levels of occupant safety. These added demands not only diverted some of the available resources away from efficiency goals, they often ran in direct conflict. For example, when you are required to provide a front bumper which will absorb the energy of a 5-mile -per-hour barrier collision, you must add both hardware and structure to the vehicle. This adds weight, and increased weight reduces miles per gallon."

Jan 1, 1983

By D. M. Ward, J. H. Ahrens

"The Fond-du-Lac uranium deposit was delineated primarily by percussion drilling and a small program of diamond drilling. Drillcore samples from three diamond drill holes as well as digitized gamma logs from percussion and diamond drill holes were utilized to define and implement an algorithm for the conversion of gamma-log data to equivalent-grade data. The procedures and detailed analysis for the provision of assay data for uranium reserve estimation are documented.IntroductionThe Fond-du-Lac uranium deposit is on the south shore of Lake Athabasca, approximately 2 km southeast o f Fond-du-Lac , northern Saskatchewan. It is on the northern rim o f the Athabasca sandstone basin.A train of mineralized glacial erratics was discovered in 1967 by Farnok, Limited by means of a helicopter-borne radiometric survey. In 1969, a program of diamond drilling by Famok was successful in locating in-situ mineralization in the Athabasca sandstone at the apex of the mineralized boulder train. Since 1974, exploration and development work have been performed under a joint-venture agreement between Eldorado Nuclear Limited and Famok Limited, with Eldorado acting as operator.From the discovery drill hole to the development of the gamma-log to equivalent-grade con version algorithm, the deposit had been tested by a total of 222 drill holes, 210 of which were percussion holes and 12 of which were diamond drill holes. The holes are generally vertical and collared at 10-metre centres on fences spaced 20 metres apart. The deposit is approximately 390 metres long, 10 to 40 metres wide and up to 45 metres deep, and is generally confined to the Athabasca sandstone. Uranium occurs as pitchblende, coffinite and uraniferou s goethite."

Jan 1, 1983

By T. Yalcin

"This paper describes the development of a process flowsheet designed to provide high dewatering rates and to bring about savings in tailing disposal costs. The flowsheet comprises a hydrocyclone, a settling cone and a thickener arranged in closed circuit. The mill tailing, after pulp density adjustment, is fed to the hydrocyclone which yields two products. The underflow product is sent to the settling cone for further dewatering. The overflow product, together with the settling cone overflow, goes to the thickener which, with the aid of flocculants, gives a clear effluent and a relatively dilute underflow. The latter combines with the original mill tailing to form the hydrocyclone feed. Solids finally leave the system in the settling cone underflow which can reach pulp densities of up to 78%, making it suitable for direct disposal or for use as mine backfill.Some discussion is included for the selection and sizing of equipment required for this process. INTRODUCTIONDewatering is an essential process for the disposal of mill tailings which forms an added burden in milling practice, often with little or no return. It is, therefore, desirable to conduct this process as economically as possible. One way of reducing costs would be to increase the rate of dewatering so that savings can be made in the size of dewatering unit s which would lead to lower capital and operating expenditures.A common method of dewatering mill tailings is gravity sedimentation which is frequently carried out with the aid of flocculation. In most cases, flocculation greatly enhances the sedimentation process, but only until a pulp density of 50% to 55% is reached in the settled material.Centrifugal sedimentation in hydrocyclones can provide high pulp densities rapidly, but does not result in a clear effluent.This paper outlines a suitable combination of gravity and centrifugal sedimentations that results in an over-all high rate of dewatering. The system developed produces a material of high pulp density while at the same time giving clear effluent."

Jan 1, 1989

By J. Erik Scheel

Overview ? About Hard Creek Nickel ? Turnagain property ? Proposed power line ? Recent Preliminary Assessment ? Favourable economics ? Property Geology ? Mineralization and metallurgical characteristics of major lithologies ? Development of the acNi (ammonimum-citrate H2O2) technique ? Overview of necessary steps ? Results of the technique ? Conclusions

May 1, 2008

By P. M. Dranchuk

"SINCE their inception, the mineral industries have, from time to time, been confronted by various and sundry problems. These have been identified, attacked and solved by means of a slow methodical process peculiar to these industries. During the past decade, these industries have experienced increasing difficulty in attracting and retaining an adequate supply of manpower. This poses a situation which seems to be unlike those that came before it in that it appears to be immune to those methods of attack which were successful in the past. Despite various attacks upon the problem, its seriousness appears to be increasing at an increasing rate. The point has now been reached where the President of AIME recently expressed the opinion that this is the most serious problem facing these industries at this time (1). Another observer has gone so far as to state, ""Given the motivation and the determination, the crisis in mineral education in Canada, can, in time be met. But it will take a generation if we Start DOW (2)"".Part of the difficulty arises out of the identification and assessment of the problem itself. For, although the manpower shortage has been developing over a fairly long period of time, there still appears to be no unanimity concerning its seriousness and the nature of the threat which it poses. Some observers continue to maintain that the current situation is not new at all, but is merely the reappearance of something old which is cyclic in nature. They observe that in the past there were numerous periods where the mineral industries encountered manpower shortages but that, in each instance, the situation eventually rectified itself. Furthermore, they draw attention to the fact that the current problem is not confined to the mineral industries but that in fact all industries are experiencing an increasing manpower shortage. They are therefore confident that if left alone the present problem will eventually disappear."

Jan 1, 1967

By Philip M. J. Gray

"The real cost of conversion from ore to semi-fabricated non-ferrous metals has been increasing for many years. Consumer resistance and improved knowledge and techniques now available justify investment in revolutionary as well as evolutionary methods of extraction. Metallurgical factors in current practice which preordain high production costs are identified as: smelters' demand for clean minerals, use of processes with low intensity of working per unit of reactor volume, use of low-velocity reactions, use of long reactor retention times relative to the speed of reactions, dilution of values in solution and commitment to electric power as a source of energy.Six new types of flowsheet are proposed for processing from ore to metal, composed of steps which are economic to construct and maintain and making maximum direct use of fossil fuel and the energy content of minerals. The basic knowledge and technology for developing these flowsheets exists. It is very tentatively suggested that these routes might reduce the capital and production cost for conversion of ore to metal by 30-50%."

Jan 1, 1980

By Alf Hartling

"Most of the Paleozoic section of the Williston Basin is a thick accumulation of numerous carbonate to evaporite, shallowing upward, cyclic sequences. These sediments were deposited in broad epeiric seas, and the deposition of the evaporite facies marked the final stage of each cycle. Many of the sequences display a pervasive replacement dolomite in the uppermost portion of the carbonate units. This secondary dolomitization is, at least in part, an early diagenetic event, synchronous with evaporite deposition.The inception of evaporite precipitation resulted in the seepage of a dense, Mg-rich brine into the underlying sediment. The heavy brine moved down the gentle regional dip displacing the more normal marine interstitial pore fluid and dotomitized the primary calcitic sediments en route. The supply of Mg-ions decreased away from the source, and correspondingly, the degree of dolomitization decreased and larger crystals formed because of slower nucleation at fewer sites.The seepage refluxion of dolomitizing brines gave rise to the frequently observed textural variation of cryptocrys talline, impervious dolomite grading into a finely sucrosic, permeable dolomite down-dip. This diagenetic facies change provides the critical up-dip barrier for potential hydrocarbon reservoirs. The lateral pool boundaries are controlled by either structural relief or a similar diagenetic facies change. The reservoirs are capped by the tight evaporites.Hydrocarbon production is attained from diagenetic traps in the Mississippian Oungre Zone and the Ordovician Red River 'C' Zone . Reservoir creation and the pooling mechanism are the result of dolomitization by the seepage refluxion of dense, Mg-rich brines beneath restricted, hypersaline lagoons. When formulating an exploration/ exploitation program for these oil prone horizons, it is essential to understand the complete geological history in order to establish where the reservoirs will be found and to define the areal extent of each accumulation."

Jan 1, 1984

By Robert Voisey, Robert J. Spencer

"LynnGold's MacLellan Mine is located about 8 km south east of Lynn Lake immediately to the east of the Keewatin River (Fig. I). The property is accessible by an all-weather road, leading north from the provincial highway 391, which links with the Town of Leaf Rapids and the City of Thompson to the south.The ore body, as outlined in the original feasibility study, is expected to produce in excess of 9.3 x IQ6 gm of gold and silver over the next 5 years. However, the deposit is open to depth and exploration is continuing on and around the main zone and the many satellite deposits.The start of construction of the MacLellan Mine and mill was scheduled to phase in with the closure of the Fox copper-zinc mine located 48 km west of Lynn Lake. The majority of the employees from the Fox Operation were either employed at the MacLellan Mine or relocated to Sherrin's Ruttan Operation.GeologyThe MacLellan gold ore deposit is located on the northern section of the Lynn Lake Greenstone Belt known as the Rainbow Trend. This Trend is a 40 km gold bearing rock sequence extending both east and west from the MacLellan Mine. The southern section of these two east-west trending structures is known as the Johnson Shear, this is also gold bearing."

Jan 1, 1990

By Theo Mayer

Presentation Outline Define data visualization in the context of workflow Present other industries? application and demonstrated benefits Provide conceptual tools to help you address a visualization strategy Hold 10,000 foot view ? to touch on many issues

May 1, 2008

By John A. Meech, Irene E. Cristoveanu

"The separation of hematite fines (100% - 38 um) from quartz fines (100% -75 um) was investigated using coarse hematite (-212 + 150 um) as a carrier in an oleic acid collector system. Oleic acid additions, per cent coarse additions, combined conditioning time and ferric chloride additions were examined.It was found that carrier flotation is a dominant mechanism for fine hematite recovery at oleic acid levels greater than 200 g/t and coarse additions of 10 per cent. Hetero-aggregation is favoured under conditions of lower levels of oleic acid in the presence of ferric chloride and at conditioning times greater than ten minutes.Ferric chloride acts as a depressant for pre-reagentized coarse hematite at oleic acid levels below 150 g/t. At concentration levels above 500 g/t, ferric chloride interferes significantly with the success of carrier flotation of fine hematite.The sensitivity of carrier flotation to changes in oleic acid addition, ratios of fine and coarse material, conditioning time and the presence of an inorganic electrolyte emphasizes that its application is only suitable when flotation conditions can be stabilized.IntroductionThe production of fine material is unavoidable during the comminution of iron ore . Due to the difficulty of recovering iron from this fine material by various gravity separation methods, flotation can often be a more attractive process producing high-grade material at high recovery. One variation of the flotation process, that can be useful for recovering ultra fine minerals (<10 um) , is known as carrier flotation. This process involves the utilizat ion of coarse particles ( > 150 p.m) which act as flocculation centres to which the fine hematite particles (10 - 40 u.m) become attached and are carried or "" piggy-backed"" into the froth phase."

Jan 1, 1985

By A. MacKinnon, P. W. Kingston, W. F. Caley

"Wollastonite (CaSiO3]) is experiencing increased usage in a variety of applications, such as fillers in paints, plastics and resins, as an extender to replace both non-fibrous and fibrous materials (e.g. asbestos), and in the glass and ceramics industries. Significant new deposits of wollastonite have been discovered in Marmora Township, about 175 km northeast of Toronto. The geological setting of these large-tonnage. High grade deposits has recently been investigated to assess the possibility of their development. A preliminary study of the chemistry, as well as the mineralogy of six occurrences is presented. Based upon this information, it is suggested that several of the deposits have an excellent development potential.INTRODUCTIONWollastonite is an anhydrous calcium metasilicate (CaSiO3), with a theoretical composition of 48.3% CaO and 51.7% SiO2; the calcium may be partially replaced by iron, manganese, magnesium, and strontium. Commonly associated minerals include diopside, tremolite, idocrase, grossularite andradite, quartz, and calcite. Wollastonite forms as a contact metamorphic mineral within impure limestone near intrusive bodies of granite, or other acidic rocks, as the result of metasomatism of calcareous sedimentary rocks, or by the crystallization of certain magmas (e.g. carbonautes). Generally, the reaction of calcite with silica to produce wollastonite occurs when siliceous hydrothermal fluids from a granitic intrusion or primary silica in the limestone/marble react with calcite in limestone at temperatures between 450°C and 600°C."

Jan 1, 1989

By J. Béland, C. Giguère

"The auriferous mineralization at the Sigma-2 gold mine occurs in quartz-carbonate-tourmaline veins emplaced in a fractured granaphyre layer in the upper part of a differentiated gabbro-diorite sill. Kinematic indicators show that fracture planes were active as strike slip, dip-slip (reverse) and tensional faults.Measurements of attitudes of fractures and movement vectors indicate eight different sets that can be grouped into three systems: (I) an east-west oriented system includes a subvertical set and two other sets dipping north and south respectively; (2) a subhorizontal system of two conjugate sets bisected by a third tensional set; and (3)a system of sub vertical conjugate northeast and north-northwest trending sets.Kinematic analysis indicates that the subvertical set of the east west system was subjected to dextral strike-slip movement activated by a northwest-southeast compressive stress whereas the bulk deformation resulting from the remaining and subsequent seven sets can be explained by a protracted subhorizontal north-south compressive stress.The valuable gold mineralization is found principally in the fracture-filling veins of the subhorizontal system and subordinately in the other sets; among these other sets, the NE trending subvertical one is slightly more favourable.The over-all tectonic picture is that of an early mild dextral strike slip faulting in a ductile-brittle medium followed by a general flattening involving, first, a vertical and, later, a lateral extension by fracturing in a medium that had become brittle.The structural features are such that the differentiated sill could not be the source of the auriferous hydrothermal solutions."

Jan 1, 1990

By B. J. Morash

"The six mineable coal seams at Quintette Coal Limited (QCL) vary in thickness from 0.75 m to 9.5 m and include waste partings varying from 0.2 m to 4 m thick. They are highly faulted and folded in some areas and dip angles range from horizontal to 90 degrees. Due to this variation in thickness and orientation of the seams, several different mining methods are used to economically recover the coal. The key to QCL&apos;s success depends on the timely collection of detailed geology data and on mine planning which allows selection of the best method of mining to achieve maximum coal recovery with minimum dilution and cost. This paper will describe the various methods of mining employed and the criteria used to select them. IntroductionThe unique challenge in mining at Quintette Coal Limited (QCL) is to extract large quantities of coal and waste, from a complex orebody, with constricted areas for mining and waste disposal. This challenge dictates the mining of as many as four 10 m benches per year, through complicated coal structures, from three separate open pits with a total of 19coal seams. This total is made up of 5 seams at Mesa, 8 seams at Wolverine and 6 seams at Shikano (Fig. 1).Computer-aided mine planning and scheduling is carried out on a routine basis to ensure the prudent selection of methods of mining, to produce plans which ensure delivery of appropriately blended raw coals to the plant, and to coordinate disposal of large quantities of waste.Several methods of mining are applied simultaneously, and as a result coal and waste are released at different rates from twelve to fifteen mining faces. In order to ensure uninterrupted flow of material from excavators and to utilize the truck fleet effectively, a computerized dispatch system is employed.GeologyGenerally, geological conditions can be related to structural (faults and dip angle) and/or stratigraphic (coal seam and interseam waste thickness) sources"

Jan 1, 1988

By M. Ghiani, P. Carbini, R. Ciccu, C. Del Fà

"This paper is concerned with the problems inherent in the efficient and economical processing of the fine fractions of a coal from the Sulcis basin (Sardinia, Italy) whose characteristics are typical of low-rank coals occurring in the Mediterranean region. Three different techniques, based upon surface properties, are examined. Flotation can be very efficient from both a technical and economic point of view, provided care is taken in the modulation of the flotation pulp. Interesting results have been obtained with oil agglomeration and this method could be economically feasible. Finally, electrical separation has proven a viable technique, although it entails preliminary drying.Besides discussing the problems encountered in the experimental research, some significant results of general validity are also given. They demonstrate that cleaned products can be obtained with fairly interesting recoveries, thus opening the way to advanced research aimed at setting up the most suitable technique for industrial application. IntroductionAs a result of the oil crisis, which caused a major upset in world energy supplies, the last ten years have seen a revolution in the energy policies adopted.In particular, the status of coal, which seemed destined to decline in view of the availability of liquid fuel, has had to be re-examined. The need to meet energy demands under improved reliability conditions and controlled prices through a broader and more flexible diversification of sources of supply has evoked, especially in highly industrialized countries, a renewed interest in coal. The result has been a consistent increase in demand and production as well as investments in new mines and the reinforcement of the infrastructure.This turn of events has also lead to a re-evaluation of young low-rank coals, hitherto considered uneconomical and thus neglected, because of their low heat value. In fact these coals, which have a high ash content, may also be relatively highly contaminated with sulphur. The above drawbacks, which still today preclude the widespread use of these coals, are bound to create even greater problems in the future as increasingly restrictive environmental control imposes, without exception, recourse to cleaner fuels."

Jan 1, 1986