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By I. M. Santos Moraes

The control of minor impurities (mainly As, Sb and Bi) in copper refineries has been a great challenge. Caraiba Metais' copper refinery produces a very high quality copper, registered in LME as grade A, and recognized as amongst the top ten in the copper world. At Caraiba's Tankhouse Bi and Sb are controlled by means of electrolyte bleed-stream removal after partial decopperizing in a set of electro-winning cells (liberators). Another way of reducing the Sb and Bi content in the electrolyte is by means of the arsenate precipitation chemistry. It is well known that the use of high arsenic concentrations in copper refinery electrolyte has the advantage of causing most of the bismuth and antimony to report in the anode slimes. However, the use of such mechanism of control may contribute to other undesired problems such as antimony and bismuth precipitation in the bulk of the electrolyte, what may cause severe contamination problems. This paper describes a period when some cathode contamination with Sb occurred at Caraiba Metais' Copper Refinery. It also presents an analysis of several process parameters related to the problem, the possible causes for the contaminations as well as the actions taken to correct the problem.

Jan 1, 2007

By R. W. Nice

"The Similkameen Mining Company property is situated about 9 1/2 miles south and west of Princeton B.C. Owned and operated by Newmont Mining Corporation, mining is presently taking place in the Ingerbelle pit. At 15,000 tpd of 0.50% Cu ore the Ingerbelle pit is sufficient for about 8 years. Another 8 years ore supply is available from the old Granby workings of the Copper Mountain property which operated from 1927 to 1957.The pit operations commenced in late 1970 with the concentrator starting in March 1972. Designed and built by Bechtel Corporation under the supervision of Newmont the concentrator's design was based on single-stage crushing and single-stage modified autogenous grinding. The modification was installation of a crusher to crush the critical size build-up. The description of the operation follows.CRUSHERThe primary crusher is an open pocket Allis-Chalmers. 54"" x 74"" gyratory. The basic closed side setting is 8"". The crusher is fed from one side with 100 ton Electra-haul trucks. The crusher pocket discharges to a 96"" wide conveyor belt, then to a 48"" conveyor system including a stacker belt. The crushed product is piled on a stockpile with a capacity of about 30,000 live tons. This stockpile feeds the concentrator."

Jan 1, 1975

By E. Contestabile, T. R. Craig

"This report describes the development and effective use of shaped charges as part of the Elliot Lake Mine Roof Stability Project to remotely remove the heads from roof bolts. With a slight modification, these same shaped charges are being recommended f or use to the Brunswick Mining and Smelting Corporation Limited (Mining Division), to cut steel cable bolts.IntroductionThe Canadian Explosives Research Laboratory (CERL) often receives requests to cooperate in solving problems encountered in private industry or other sectors of the government. CERL is equipped to design and test explosive and pyrotechnic devices and the policy is to treat each case individually.The first case reported evolved from a request from a sister laboratory at Elliot Lake. The intent was to remotely remove the head s of roof bolts as part of a mine roof stability project. The device designed for this use was 1000,70 effective in the laboratory and 80% effective in the mine.The second case reported results from a request from a private mining company knowledgeable of the Elliot Lake Project. Their requirement was to remotely cut cable bolts. This request was first treated as presenting a new problem. The solution, however, proved to be very similar to the former."

Jan 1, 1985

By G. H. Hope

"Pamour Porcupine Mines of Timmins, Ontario operates two 3,000 ton per day concentrators which receive ore from eight to ten mines in the area. The area milling concept was adopted by Pamour in 1971 and has been used successfully since then. The purpose of this paper is to discuss the advantages and the problems of area milling. Pamour Porcupine Mines Limited operates two 3,000 ton per day concentrators which receive ore from eight to ten mines in the Porcupine region. The area milling concept was adopted as the route to survival for Pamour and has worked successfully. HISTORICAL BACKGROUNDProduction of gold from the Porcupine region in Northern Ontario started in the early 1900's and has been continuous since that time. Some of the major operators were companies such as Mcintyre, Hollinger, Dome, Pamour, Paymaster and the list goes on. An underground survey would reveal hundreds of miles of drifts and raises. The main group of mines extends from South East of Timmins to the Pamour Mine, 15 miles to the east. During the lean years of the sixties when gold prices were low, labour costs were rising rapidly, and ore grades were dropping, many of the area mines closed down their operations."

Jan 1, 1981

By R. D. Brown

In the spring of 1977, Revenue Canada announced its intention to proceed in 1978 with a plan to impute a taxable benefit on interest-free and low-interest loans provided to employees. Such loan arrangements are often an important aspect of the compensation packages provided by many companies to their employees. Since the original announcement, there have been many submissions to Revenue Canada opposing this change, and the Finance Minister has now brought down a compromise solution with the introduction of a proposed amendment to the Income Tax Act. The amendment, which would not take effect until the 1979 taxation year, would require an employee, a shareholder or a related person to include a benefit in income measured as the difference between the interest on any such loan computed at bank prime rate and any interest actually paid. Only the amount of such a benefit in excess of $500 in a particular year would be required to be included in income. Of particular interest is the exclusion from these benefit rules of loans up to $50,000 in respect of the purchase of a house on the relocation of an employee and loans provided for the purchase of shares of an employer corporation.

Jan 1, 1978

By A. Jeffkins

Visibility is restricted when operating load haul dump vehicles resulting in a number of serious accidents in the Ontario Mining Industry. One of the leading causes of these accidents is the inability of the equipment operator to see clearly people, objects or hazards around the machine. Previous line of sight testing by the research team found specific machine characteristics were responsible for blind spots and impaired visibility. In order to identify feasible design modifications a computer simulation program, Classic JACK 3.1, was utilized. Program features include human factors analysis, which allows evaluation of line of sight and operator posture in order to decrease risk of musculoskeletal injury. Research within the virtual computer environment consisted of a Visibility Audit and a Target Audit in order to quantitatively determine how certain components of the LHD design affected the line of sight around the vehicle. Results indicate that modifying the LHD light brackets, engine profile, cab posts and other components will enhance visibility. The addition of cameras located on the front and rear of the vehicle were able to enhance the operator?s sight lines to previously obstructed areas. Modifications to seat height and the operators orientation both improved sightlines and decreased risk factors associated with back and neck musculoskeletal disorders.

May 1, 2003

By R. S. Nichols

"During 1973 to 1978, Canadaka Mines Limited, a subsidiary of St. Joseph Explorations Ltd., undertook an extensive exploration and development program in the Cobalt area. This program resulted in the delineation of previously unknown stratigraphic units in the Archean volcanic sequence. During this time period, significant are controls related to area silver deposits were also identified.The Archean geology is comprised of a volcanic pile conformably overlain by sediments. The volcanics contain at least two felsic volcanic centres near the stratigraphic top of the pile. The bulk of the pile consists of mafic flows and interflow sediments. lnterflow sediments around silver are shoots contain mineralized halos of base metal sulphides. The halos exhibit lateral and vertical metal zoning with Cu, Pb and Zn mineralization decreasing away from an are shoot.Silver mineralization controls determined during the Canadaka program agree with the historically well established importance of Coleman sediments as well as Archean contacts for hosting silver deposits. The vertical extent of are shoots is typically 150to 250ft. A strong correlation was found to exist in the Cobalt area between Archean strike and the strike of are veins. Finally, al/ Cobalt area are deposits appear to be associated with a distinct volcanic pile at the top of a sequence of Archean flows."

Jan 1, 1988

By T. Belem

The main objective of this study is to better understand the effect of underground CPB placement conditions on its microstructural, hydro-mechanical and geochemical properties. To reach this objective, three PVC columns, each 3 m high, were built, and were filled with CPB material. The columns allow simulating undrained (UD), half-drained (HD) and fully-drained (FD) conditions along with the measurement of resulting self-weight consolidation settlement of the CPB. Bleed and drainage waters were also collected from each column for geochemical analyses (pH, Eh, EC, SO42- content). After 90-days of curing time, a total of sixty CPB samples were cored from the backfill columns and subjected to uniaxial compression tests followed by physical characterization (Gs, void ratio, water content, degree of saturation, specific surface area). The results showed that the total drainage water and the maximum observed settlement occur mainly within the first 72 hours after the columns are filled. The corresponding volumetric strains suggest that in situ backfilled stopes simulated behave in a similar way to the fully-drained (FD) or the half-drained (HD) conditions. The MIP test results show that the pore structure varies between the top and the bottom of each column.

May 1, 2007

By R. Ham-Su, J. P. Healey, S. P. Farrell, R. S. Underhill, M. A. Gharghouri, C. V. Hyatt, L. M. Cheng

Magnetic shape memory alloys (MSMA's) are a class of materials where magnetic energy can be converted into mechanical energy and vice versa. NiMnGa-based MSMA's have attained magnetic field induced strains up to approximately 10% and have a relatively wide operating temperature range, from well below 0°C to above RT, making them very attractive for a variety of applications. However, these materials also suffer from low toughness. Using these materials in a composite could mitigate this shortcoming, and also overcome limits imposed by inertia and eddy current losses. In this work, we describe the manufacture and characterization of such composites. Composites with 30% by volume MSMA were fabricated under a magnetic field resulting in anisotropic magnetic properties. Damping properties were evaluated by dynamic mechanical analysis.

Jan 1, 2004

By H. C. Cooke

"The Eustis mine, which was discovered in 1865, lies about 6 miles southwest of the city of Sherbrooke, Quebec, in lots 2, 3, and 4, range 9, Ascot tp. The mine was operated almost continuously from 1865 to 1937, under vanous owners.The ore was pyrite with varying amounts of chalcopyrite, a small amount of zinc blende and galena, and a low content in gold and silver. Parts of it ran quite high in copper, but the mine average would probably have been between 3 and 4 per cent. The high percentage of pyrite made it profitable to separate the ore into a copper concentrate and a pyrite concentrate. The latter was shipped away for manufacturing sulphuric acid, or was treated in a plant erected in 1887 at Capelton by the Nichols Chemical Company.The ore is a replacement of mica schist, which in turn was formed by the shearing of rhyolite flows. Ore also replaces the 'green rock', a term locally applied to carbonatized mica schists. The ore contained numerous 'horses' and smaller fragments of country rock, in all stages of replacement, ranging from those whose character was quite distinct to those whose ancestry could only be detected by an indefinite banding preserved in the sulphides."

Jan 1, 1954

By F. Dai

Due to difficulties associated with gripping in direct tension, indirect methods are commonly used to measure rock tensile strength. In this work, we adopt an innovative indirect tensile test method: Semi-Circular Bend (SCB) to measure the tensile/flexural strength of Laurentian granite (LG). The static tests are carried out with a servo-controlled material testing machine and the dynamic tests are conduced with a Split Hopkinson Pressure Bar (SHPB) system. Pulse shaping technique is adopted to achieve dynamic force equilibrium in SHPB to facilitate data regression. Finite element method is used to relate the failure load to the tensile strength. Strong rate dependence of the tensile strength is observed. The flexural strength is higher than the tensile strength measured using Brazilian Disc (BD). This difference is rationalized using the non-local theory. To further validate the method, a coupled Finite element/Discrete element method (Fem/Dem) in conjunction with the smeared crack model is utilized to simulate the fracture process during dynamic SCB tests. The resulting fracture patterns are qualitatively consistent with those from recovered samples. Both the experimental and numerical methods have validated the results and this new method is readily to be used for other rocks and other brittle materials.

May 1, 2009

By J. H. Gray

"IntroductionIn 1980, Fording Coal Limited started conceptual planning studies which led to major changes in the long-range mining plan at their Fording River Operations. These new plans have been completed and are now in operation.To assist personnel in a timely completion of this major revision to the long-range plan, existing in-house drill hole data base and scheduling systems were used and a computerized Mine Modelling and Planning System was purchased. With these tools, plan s were developed which led to completion of initial access to the peak of Eagle Mountain and the start of mining operations in March 1983. As mining area s open up and new geo logical data is obtained, detailed plan s are being extended and revised.With the geology and mine plan s on line, this work can now be done with less effort and plans ca n be adapted to provide flexibility in mining operations. Changes in market conditions can be accommodated by moving mining operations into different seams for different coal types. The computer systems are used to revise pit designs and schedules accordingly."

Jan 1, 1986

By L. Byszynski

The results of a three month evaluation of the application of EMEW® technology at the KGHM Glogów II Smelter tank house bleed stream are presented. The current, conven¬tional electrolyte decopperization process has some limitations, including: only a fraction of its production is commercial grade cathode copper, significant operating costs, low current efficiency, low current densities resulting in low copper depletion rate, and arsine gas and sulphuric acid emission. The EMEW® cell technology developed by Electrometals Technologies Ltd. can overcome many of these limitations. Tests were performed on a pilot EMEW® installation comprising 30 cells at ambient temperature on electrolyte bleed, using current densities between 100 and 600 A/m2 , with copper concentrations between 45 and <1g/dm3. Results showed that a high grade copper can be obtained to the level of 7 g/dm3 of copper concentration in electrolyte. The use of EMEW® technology allows the direct and efficient recovery of over 85% of the copper contained in the bleed electrolyte. Glue & thiourea addition were tested in order to improve the parameters of the copper depletion process. The behavior of Arsenic and Bismuth was observed and a means for their elimination from the system proposed. On-line copper concentration monitoring is proposed to improve control and performance.

Jan 1, 2007

By J. K. Van Beek

The Deep Underground Science and Engineering Laboratory (DUSEL) is a scientific facility that will be placed in the deeper reaches of the Homestake mine, Lead, SD. Our team of geologists and engineers is carrying out the first scientific project awarded to the site ? Towards a Transparent Earth. Taking advantage of the thousands of open exploratory and sand-line holes, we are installing the beginnings of a seismic observatory. Each installed station consists of a 3-D accelerometer package and a 1 nanoradian 2-D tilt meter. In order to allow for a variety of monitoring and characterization studies, the array instruments are sensitive over the frequency bandwidth of 0.2 - 1 KHz. Three, three component accelerometer stations are currently installed ? in a 140 m deep bore beneath the slurry pump house, and in 12 m deep bores on the 2000-foot level, 800 and 400 m from the Ross shaft. There is a tilt-meter installed at each 2000 level station. These installations are in 150 mm diameter sand-holes. From the currently installed tilt sensors we are investigating solid earth deformation as a response to tidal potential. The accelerometers are being used to locate and characterize events associated with mine dewatering and rehabilitation.

May 1, 2009

By Bo R. Arvidson

"New permanent magnetic alloys have recently opened up possibilities for development of unique mineral separators. These are now making several new applications feasible. In many cases where conventional electromagnetic-induced roll separators have traditionally been used, the new permanent magnetic roll separators may reduce both over-all capital costs and operation costs.The development of the next generation of extremely powerful permanent magnets, i.e. neodymium-iron alloys, is progressing rapidly and will affect the roll separator as well as another type of magnetic separator. Permanent Magnet Roll SeparatorDesign and FeaturesDiscs of permanent magnets interleaved with soft iron discs constitute the basic magnetic roll design (Fig. I). By enveloping the magnetic roll with a thin abrasive resistant belt (Fig. 2), even highly magnetic particles are removed.The first prototype roll utilizing the new magnets was shown to have approximately equal strength as induced magnetic roll (IMR) separators. Since the initial test roll, the new separator, called the PERMROLL® , has been made twice as strong with regard to magnetic force, that is, the magnetic flux density is determined to exceed 1.7 tesla (17 kilogauss), while the magnetic field gradient is more than twice the gradient than can be practically achieved with IMR."

Jan 1, 1985

By C. John Sullivan

Is there a relationship among the Sudbury nickel ores, the Cobalt deposits, and the Huronian, Athabascan and North Australian uranium provinces? All are within intracratonic basins, with ore near basal unconformities. There are similarities in the geochemical "fingerprints" pointing to basic igneous rock affiliations. Some show a time relationship to basic igneous activity and to great rift systems. Many basic dykes show radioactivity at their edges. A spatial relationship between the uranium-cobalt-nickel ore at Midwest Lake, Athabasca, and basic igneous rock is reported. These remarks are not meant to imply, necessarily, a direct genetic connection between the basic dykes, etc., and the ore. In some cases, the relationship may be similar to that noted between basic and ultrabasic intrusives and volcanic massive sulphide ore deposits. Crustal thinning in these areas, associated with graben, appears to have favoured volcanic activity, as well as basic intrusives. Probably, the potential of the Huronian should be re thought . Athabascan-type ore may be present . New data on mineralization in Turner Township, Ontario, suggest this. The mineral possibilities of other basins should be reconsidered. It is to be remembered that the Athabascan and Kombolgie basins were neglected for many years. Intracratonic sedimentary-igneous basins contain many of the greatest mineral fields of the world.

Jan 1, 1979

By Par G. Jönsson, Joachim von Scheele, D. S. Sarma, Mukul Goyal

Dust from flue gas cleaning systems at iron and steel production is frequently considered as a waste problem, but it is actually a potential raw material source. By using a technology like the oxyfuel based OXYFINES technique, it can be melted into a suitable form. The product from this processing, however, needs to meet the requirements of a recyclable raw material, here particularly a top-charged blast furnace feed. The present work has been focused on characterization of the product produced from these dusts by OXYFINES technology. The investigation has been carried out on samples of processed dusts from a European integrated steel mill. It was done by means of chemical analysis, density measurement, light optical microscopy, X-ray diffraction, scanning electron microscopy combined with energy dispersive spectroscopy, and micro indention hardness measurement. Special attention was paid to the presence of zinc, an element that might be harmful while recycling the material (e.g., in a blast furnace). The results show that the product contains four different regions with different morphologies and properties in the material, which are discussed in detail. The overall conclusion is that by processing the dusts in this way, a raw material suitable for recycling in a blast furnace can be obtained.

Jan 1, 2004

By L. C. S. Dharmasiri, S. M. Shin, A. Senaputra, J. S. Sohn, K. H. Park, J. Avraamides

Reducing agents can be applied to leach metal values from natural and secondary resources such as laterite ores and deep sea manganese nodules and recycled materials such as spent batteries / catalysts which contain high-valent metal oxides of manganese, cobalt and iron. Selective leaching of some metals can be achieved by selecting conditions to control the saturated solubility and dissolution rates of metals from oxides or mixed metal/oxide matrices. The leaching results are rationalized on the basis of chemical species, Eh-pH diagrams and heterogeneous kinetic models. The role of reducing agents such as hydrogen peroxide, sulfur dioxide and iron(II) sulphate, in acid, alkali and in the presence of complexing ligands such as ammonia for the improvement of the leaching of metal oxides and metals is discussed. Previous studies on acid leaching of metals from nickel laterites, manganese nodules and spent catalysts/batteries in the absence or presence of reducing agents show that the rate controlling step involves the diffusion of protons through a thickening product layer on the particle being leached. It is shown that the leaching of nickel and cobalt from manganese nodules and zinc-carbon batteries in ammoniacal sulphur dioxide solutions also obey shrinking core kinetics.

Jan 1, 2014

By Joseph J. Mgumbwa

Pillars are any structures left between two or more underground openings. The stability of pillars is normally considered to depend on shape (defined by width to height ratio), rock mass strength, extraction ratio, in situ stresses and the gross structural features (i.e. joints, contacts, faults etc). Recent experience has shown that pillar stability is also controlled by the relative orientation of the orebody with respect to the in situ principal stress. In inclined orebodies, pillars are loaded in compression and shear, thus creating unsymmetrical stress distribution. Failure mechanisms of these pillars are little known. This paper investigates the failure mechanisms of pillars under shear loading. Two dimensional elastic numerical modeling was used to examine the behavior of pillars in different orebody inclinations relative to the major farfield stress orientation. First, the paper reviews pillar design approaches including the empirical pillar design chart and uses numerical modeling to investigate the effect of the major farfield stress orientation on pillar stability. It is concluded that the empirical pillar design chart be used with caution, and that for orebodies under shear loading mine planning and design should take this into consideration since such geometrical orebody/stress relations put mine structures at higher risk of instability.

Oct 1, 2010

By Timothy D. Dreger

In the spring of 2009, Suncor Energy Inc. technical personnel saw an opportunity to improve planning 0and mining of overburden material in order to address aggressive construction goals and increased mining complexity. By tying together current and historical equipment performance, geological model information, and material observation in the field new operating elevations for the shovels were developed. At the same time, methodology of recording and reporting overburden movement through the Modular Mining DISPATCH system was changed. The result of this first stage of improvements was an increase in construction-grade material available at the face. The personnel involved realized that other opportunities were available to build on the initial successes and establish processes that would stand up to attrition and experience levels. A cross-functional technical team was assembled to identify ways of further improving workflows around overburden mining. Some of the opportunities realized include greater alignment between planning, reporting and operations as well as development of reporting tools that help steward Mine Operations to the plan. All of which have resulted in Suncor meeting or beating its forecast overburden targets. The cross-functional technical team continues to seek out new and better ways of doing business so Suncor can continue to deliver on its commitment of outstanding performance and results.

May 1, 2011