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By P. K. Gummer

Gold was fir t di covered on the Seabee property in 1947 by the Con olidated Mining and Smelting Company Limited. Acquired by Claude Resource Inc. in 1984, the property is now being explored by Placer Development Ltd . in joint venture with Claude Re ources. Between Augu t, 1985 and March, 1986, Placer completed 54 drill holes, extending the main o. 2 and o. 5 vein y tern to a depth of 1000 feet below surface and di covering two new satellitic gold zone 800 feet west of the o. 5 gold zone. Drill proven and probable geological re erve in four zone ( os. 2, 5, II, 14) to a vertical depth of 1000 feet, are approximately 1,120.000 tons averaging 0.32 oz. Au/ton.

Jan 1, 1986

By Yuyong Li, Liangman Zhang, Zhaolian Wang, Shun Wang, Ltd. Shandong Huate Magnet Technology Co., Fengliang Liu

"Introduce a newly revolutionary magnetic separator - Raising Concentrate Grade and Decreasing Dregs Content Magnetic Separator Series JCTN (i.e. RCG&DDC MS JCTN). HUATE® JCTN is designed for rinsing, purification, desliming and thickening of the magnetic minerals as per different requirements. Adopting 240°-270° larger magnetic element with multi-poles and magnetic pulsation, and combining the devices of multi-channel rinsing water and top flushing water and new style tank, HUATE® JCTN can improve another 2%-10% concentrate mFe% than the traditional MS without lowering the concentrate recovery rate. Thereby, it solves the uneasy concentrate upgradation problem of the traditional MS resulting from the magnetic aggregation. Now, JCTN has been successfully applied in more than 30 mines in Australia, China and Russia, e.g. Sino Iron of CITIC PACIFIC MINING MANAGERMENT PTY LTD. HUATE® JCTN can optimize the industrial processing line by: 1) improving the discarding rate before milling to discard the necessary tailing ASAP; 2) getting in advance the final concentrate after milling. One JCTN can replace many traditional MS in series. In some way, it can also replace the anti-flotation separation process.INTRODUCTIONWe’re writing to introduce a newly revolutionary magnetic separator - Raising Concentrate Grade and Decreasing Dregs Content Magnetic Separator Series JCTN (i.e. RCG&DDC MS JCTN). HUATE® JCTN is designed for rinsing, purification, desliming and thickening of the magnetic minerals as per different requirements."

Jan 1, 2016

By Guy Chevalier

QCM?s pellet plant, located in Port-Cartier, Quebec, produces up to 8.6 million tons of iron ore pellets annually. Four different types are produced: three for blast furnace operations and one for direct reduction furnaces. The paper presents the scientific approach that led to the installation of new process equipment to improve the reducibility of direct reduction pellets (DR pellet). The findings, the equipment selection and some post start-up modifications are presented. This low silica DR pellet is used in Midrex and HyL shaft furnaces. A good DR pellet has to meet strict chemical, physical and metallurgical specifications. An important metallurgical property is its ability to release oxygen when exposed to reducing gases. Considering that the market for DR pellets is expanding and being aware that reducibility is critical for our clients, a program to improve the latter was undertaken. Test work showed that one factor which has a negative effect on reducibility is the proportion of particles larger than 75 microns. Knowing that the best way to reduce the amount of coarse particles was to close our open grinding circuits, we began evaluating the most suitable classification equipment applicable to our process operations. We settled on hydro-classifiers based on their very sharp cut and their low operating costs. In light of the hydro-classifiers performance it was also decided to replace the hydro-cyclones of an already closed circuit.

May 1, 2003

By A. K. Alzo?ubi

Block toppling in natural rock slopes has been under investigation since the 1970?s. De Freitas and Watters (1973) introduced the term ?toppling? to describe the movements of rock slopes by rotation in steeply dipping beds. The Lornex pit case history from British Columbia (Canada) was chosen to study the effect of mining on the stability of toppling rock slopes. A discrete element approach that allows fracturing of intact material was applied successfully to model the composite rock slide-rock topple movement. Three main movement modes were observed in the field and the numerical model; the sliding of the top of the slope exposed normal scarps, the toppling at the middle part of the slope exposed obsequent scarps facing opposite to the slope face, and dilation of the rock caused by fracturing at the toe formed loose material. The development of the rupture surface at the toe of the slope was traced and did not evolve into a continuous rupture surface throughout the slope both in the field and the numerical simulation. Good agreement was achieved between the deformations recorded in the field and the numerical simulation.

Jun 1, 2012

By John Steele

The goal of this project is to detect the presence of objects behind haul trucks and to provide an alarm to the driver if such objects are detected. Objects of interest include people, pickups, other equipment, and large rocks. Another goal is to see if the system can identify the existence of a berm and determine the distance from the truck to that berm, so a safe backup distance can be computed and used as a reference. This paper presents results that demonstrate that such a system is feasible and includes results from work at a local quarry. Architecture of the system is provided and the various subsystems are discussed. Details of the algorthims are included and discussion of the issues involved in developing a fieldable system are also included.

May 1, 2003

By Narasimha Mangadoddy, Balraju Vadlakonda

"Bubble size distribution, bubble rise velocity and gas and solids hold-up are the key major hydrodynamic parameters that are extensively used for column flotation design and performance evaluation. The distribution characteristics of mean gas hold-up is studied using electrical resistance tomography (ERT) coupled with pressure transducers (PT) in column flotation. The ERT technique facilitates non-invasive and nonintrusive visualization of different flow regimes even in the presence of particles in a column flotation. The effect of superficial gas velocity, feed flow rate and slurry height in the column on mean gas hold-up and its radial distribution has been analysed for both two-phase and three phase flows. Experimental results show ERT coupled with PT is suitable as an online monitoring tool to provide useful information on the three-phase flow hydrodynamic parameters of the column flotation. The tomography images, which were generated using a modified sensitivity back projection algorithm, are employed to explore the influence of parameters in two phase flow in column flotation. Mean gas and solids hold-up values extracted from ERT have been critically analysed for the column operating in various flow regimes. Gas hold-ups and solid hold-ups results using ERT are in very good agreement with conventional estimation and correlations obtained using pressure transmitter methods. Meanwhile, the results show that the gas hold-ups in the centre region increase constantly with an increase in the superficial gas velocity, whereas solid hold-ups distribution is very heterogeneous for high gas velocity. Furthermore, the results also indicate that ERT is a very powerful tool for diagnosing the 'inside' flow behaviour of gas –liquid–solid three phase flow in columns operating for a wide range of flow regimes.INTRODUCTIONColumn flotation is perhaps the most significant technological innovation in flotation machinery and its successful introduction in mineral processing plants. There has been a lot of attention in understanding the various mechanisms that take place during operation. Due to many reasons column flotation has been found to yield better performance than conventional flotation cells, particularly with fine particles (Honaker & Mohanty, 1996). Due to complex flow behavior in nature, the performance of column flotation influenced by on flow characteristics of the process, (Jena, Biswal, Das, & Reddy, 2008). Previously basic research is carried out to evaluate the effect of the hydrodynamic parameters on performance of column flotation (Finch, J.A.;Dobby, 1991). Many techniques have been developed that could be used to experimentally analyse the hydrodynamics of column flotation. Tomography techniques are well sound to investigate the hydrodynamics for process equipment. Among that, Electrical resistance tomography (ERT) has been used in various industrial investigations for visualization of the concentration profiles and characteristics of the fluid dynamics in gas–liquid two-phase systems (Wang, Dickin, & Mann, 1999; Williams, R.A; Wang, 2000). ERT is an imaging technique to analyse the internal flow behavior non-intrusively. ERT provide very useful tools for measuring and monitoring of column flotation process on line. Due to its high speed capability, low cost measurement, robust sensors, ERT is considered to be the most powerful tool among other tomography techniques such as positron emission tomography (PET), magnetic resonance imaging (MRI), optical and infrared tomography. Application of ERT has extended in process systems due to its improved speed of data acquisition, sensitivity, flexibility and noise immunity. In multiphase flow of bubble columns, gas hold-up and solid hold-up are explored by using the coupling of ERT and difference pressure method (Jin, Han, Yang, & He, 2010)."

Jan 1, 2016

By Dorothy Walters

As an increase in the number of producers alters fact ors affecting supply, long-term prospects in traditional markets for many minerals weaken. At the same time, conflicts between national and international objectives undermine existing competitive elements in mineral markets and Canadian costs escalate. Such changes may dramatically alter the environment in which the mining industry operates.

Jan 1, 1979

By Akihiko Nishiyama

Unmanned construction technology used for remote control operation of construction machines has some problems to solve compared with manned operation of construction machines, such as fatigue due to long-term operation or decreases in operational efficiency. To solve these problems, we recorded the viewpoints of operators in both manned and remote control operation and analyzed the differences. This paper reports on our discussion of improving the operability of remote control operation based on the analysis results.

Aug 1, 2013

By M. Somppi, Z. Yamak

"Gold producers invest significant effort in mining, processing, and creating an intermediate gold doré product. Nonetheless, equal effort should be extended to the final handling and processing of the doré bar, and managing the high-purity gold produced at the fine-gold toll refiner. This detailed attention to bullion handling and refining provides rigor and confidence that the mine site is achieving, through fair and controlled methodology, the most appropriate value for the final product. With the above in mind, the following study explores the importance of preparing a set of site best-practices for bullion handling and specifically, detailing the peculiarities of sampling methodologies and the impact on assays.INTRODUCTION Gold and silver handling practices are common place at mine sites and refineries. The practices include but are not limited to smelting, ingot casting, weighing practices, and secure transportation. Proper handling and processing of the bullion material ensures that the mine site is achieving the true value of the final product. Various handling aspects can critically impact the perceived value of the bullion. A few of these particulars include weight tracking, scale recertification and calibration, refining and melting practices, melt temperature measurement, sampling, pouring, bar cleaning, furnace technology and crucible selection, and assaying. Nevertheless, this report discusses and focuses on the importance of proper sampling and molten-metal temperature measurement and their potential impact on the final doré bar value. Refining or re-melting operations achieve a proper measure of the precious metal content of its bullion when the sample accurately represents the whole bar. At first this task appears seemly straightforward, however, taking a representative sample can be challenging and is also one of the most important tasks for valuing gold during the settlement stage at the precious metal refinery. Various bullion sampling methodologies exist; including: dip sampling, granulation, drilling, cutting, and vacuum pin sampling. The Royal Canadian Mint (2009) indicated in their technical review of refinery operations that pin sampling is one of the best methods for cases where representative sampling and accuracy are required, e.g. to determine the payable metal content. Pin sampling consists of inserting a sealed glass vacuum tube (Figure 1) into the molten metal; when the molten metal contacts a purposely-designed weak portion of the glass, the seal breaks and the metal is suctioned into the hollow centre (Figure 2)."

Jan 1, 2018

By T. C. Crosby

"Grinding has a marked effect on concentrator recovery and operating cost, and improved operation through automatic control can enhance plant performance. The correct application of automatic control can only be accomplished after the basic process variables and their effect on mill operation have been defined. This paper develops a control system for a closed circuit grinding system. Typical control systems, such as those for feed, water flow, level and circulating load, are discussed. A method of determining controllability, using the calculated reaction curve technique, is outlined. Various successful automatic grinding control applications are discussed and future possibilities are outlined. Although this paper primarily deals with closed wet grinding• circuits, the principles involved can be readily applied to other processes."

Jan 1, 1967

By W. L. Ott, C. L. Lewis

"AbstractA technique is described for preparation of palladium sponge and for spectrochemical analysis of the metal in this form. The precision and accuracy of the method are discussed. Analyses are compared with previous spectrochemical analyses of palladium in the black form. Good agreement was found in the two sets •of results and it is concluded that they are more reliable than wet chemical .analyses of the same material.IntroductionFOR SEVERAL YEARS the problem of platinum metal analysis by spectrochemical methods has been under investigation at the Spedtrographic Laboratory, Department of Geological Sciences, Queen's University. The problem, briefly -stated, is as follows: Samples of platinum, palladium,-rhodium, ruthenium, and iridium are received as fine metal powders, called sponge. Direct spectrographic analysis of this material has not been found satisfactory due to its heterogeneity •as regards contaminant metals, which may be present up to a total of one per •cent or more. Further-more, spectrographic standards are difficult to obtain and difficult to prepare accurately by adding weighed portions of contaminant metals to the sponge. The fact that •contaminant metals in original samples are probably alloyed with the major constituent is a further difficulty since complete fusion of these refractory metals proved impractical in the present case as a means of standard preparation. It •has, therefore, been found most satisfactory to dissolve the metals, prepare standards by addition of solutions of contaminant metals, and to reduce both standards and samples to a homogeneous form. A previous paper, by Hawley, Wark, Lewis and Ott (2) dealt with a method for spectrochemical analysis of platinum and palladium in their black form. Since completion of research on the black technique, the possibility of analyzing palladium accurately in its sponge form has• been investigated."

Jan 1, 1953

By J. Beland

The Rimouski-Matapedia region is along the southwestern extension of the central Siluro-Devonian synclinorium of Gaspe Peninsula. As in Gaspe about 30,000 feet of Siluro-Devonian strata rest on a "basement" of tightly folded Ordovician rocks. The central synclinorium is divided up into two northeasterly trending belts each of which is characterized by distinctive lithologies and patterns of folding. The northwestern belt is gently to moderately folded and includes lithologies which point to a stable environment. The southeastern belt on the other hand is tightly folded and the lithologies indicate a less stable environment. A marked angular unconformity separates the basement from the Siluro-Devonian cover near the north-western margin of the northwestern belt. At the southeastern margin of the southeastern belt the relationship of cover to basement has not been as-certained because of a fault. The northwestern belt has several features significant in the search for petroleum; the Silurian strata are exposed in broad open anticlines

Jan 1, 1962

By N. J. Shackleton, N. A. Chapman, V. Malysiak, C. T. O’Connor

In this study, the effect of using conventional crushing and high-pressure grinding rolls (HPGR) in combination with dry or wet milling was investigated using a base-metal sulphide (BMS) sphalerite and a platinum group mineral (PGM) ore to determine how these processes affect the flotation performance. In sphalerite, irrespective of the crushing procedure (HPGR or conventional), dry milling resulted in the highest grades and recoveries of zinc, whereas in PGMs, similar treatment produced the poorest results. The results were investigated further by the effect of factors such as percentage liberation and particle size on the flotation results.

Jan 1, 2012

By R. C. Gilmore, J. F. Brune

"Pulverized limestone rock dust used in United States underground coal mines to prevent and suppress coal dust explosions must easily disperse by forces of a methane or coal dust explosion. Moisture in the mine environment causes caking of the dust. Colorado School of Mines researchers performed dispersibility tests in a full-size explosion test drift. Tests included conventional, hydrophobized, and rock dust approved for German mines. Conventional and German standard rock dust products partially agglomerate, which may not be effective in suppressing a coal dust explosion, while hydrophobic rock dust retains better dispersibility.INTRODUCTIONA coal dust explosion devastated the Upper Big Branch mine in 2010 resulting in the death of 29 miners, the worst mining accident in the United States since 1972. The explosion propagated through approximately 65 km of active mine workings, but was extinguished in areas that had been properly rock dusted (Page, 2011). Researchers have long studied and established the ability of inert limestone rock dust to suppress coal dust explosions, see Richmond et al. (1975), Cybulski (1975), and Sapko et al. (2000).To be effective, rock dust must contribute to a total inert content of > 80% by weight and 100% of rock dust particles must pass through an 850 µm sieve, while 70% of the rock dust must be finer than 74 µm. This is established in US regulations 30 CFR §75.2. Dry rock dust is a nuisance that prevents mining work downwind from rock dusting activities. To overcome this problem, dust manufacturers have proposed applying the rock dust as a wet slurry or foam. After drying, manufacturers expected the slurry or foam-applied dust to have the same explosion suppression capabilities as dry-applied rock dust.Researchers at the Colorado School of Mines (CSM) designed and built a full-scale, underground Explosion Test Facility (ETF) at the CSM Edgar Experimental Mine in Idaho Springs, Colorado about 20 miles west of the CSM Golden, Colorado campus. To disperse the different rock dust products, researchers produced an air pressure pulse using a mesh array of PETN detonation cord. This method is simpler, more reproducible and safer than other methods considered, including methane-air explosions and a compressed air cannon. The detonation cord blasts produce a wind velocity of 30 to 50 m/s, the minimum velocity at which coal dust explosions can propagate, based on research by Nagy (1981) and Cybulski (1975)."

Jan 1, 2019

By C. Denis Thibodeau

Outline Introduction 402 OB Mining Sequence Trial to Verify Sequence Change Monitoring Observations Numerical Modelling Conclusion

May 1, 2013

By J. A. Hansuld

"THIS SESSION marks something of a milestone in that it is, as far as I know, the first session at a CIM Annual Meeting devoted entirely to exploration geochemistry. This is an indication of the general acceptance and widespread recognition by industry of geochemistry in mineral exploration. As a first, I hope it proves sufficiently successful and interesting that geochemical exploration sessions will become a routine part of future CIM annual meetings. The greater use and acceptance of geochemistry has resulted in many investigations and advances, especially in areas such as the Canadian Shield. For a first session on geochemistry, the meeting in Quebec suggested an ideal opportunity to assess these advances and report on the current application of geochemistry in the Shield. The theme of the session is ""Geochemical Exploration in the Canadian Shield - The State of the Art."" A series of six papers will be presented dealing with the various dispersion media - rocks, heavy minerals, ""soils"", lake sediments, waters and vegetation. As a background to the individual presentations, I would like to take a few minutes to briefly trace the history of the use of geochemistry in the Canadian Shield."

Jan 1, 1971

By Saikat Chatterjee, Xintong (Brett) Liu, Kinnor Chattopadhyay

Magnesia carbon bricks are commonly used in BOFs and are generally pre-heated before the BOF goes into service. Owing to very stringent emission regulations, the BOF pre-heating process need to be controlled and optimized so that, the emission standards are met. One of the major concerns in organic emissions are its stringent limits on emission rates and total volatile emissions. In the present work, an attempt has been made to integrate CFD and Thermodynamic models to predict the emission rate of volatile organics during the pre-heating process. A one dimensional heat transfer model was developed using visual basic and then integrated with thermodynamics calculations using FactSage 6.4. The parameters that affected organic emissions were the pre heating procedure, gas composition of the burner, heating rate and type of the burner. Typical composition of MgO-C bricks and binder materials were obtained from literature and vendor data sheets. Chemical reactions between organic materials, refractory and burner gasses were considered. The model predictions indicated that certain burner conditions could destroy all organics before it exits the vessel while other conditions needed the use of an after burner at the mouth of the vessel. The model was also able to predict the organic emission rates based on the chosen pre-heating profile. This kind of predictive model will be very useful for the steel industry and enable them to justify permit limit applications and stick to the limits by fine tuning their pre-heating process.

Jan 1, 2015

By Jennifer Abols

In July of 2013, Lundin Mining acquired the 2,000 tpd Eagle nickel and copper project from Rio Tinto. The project had been put on hold earlier in the year and construction was approximately 50% complete. Lundin immediately accelerated project activities and by September of 2014 the project was constructed, commissioned and ramping up. The newly commissioned facilities went on to reach design throughput, recovery and product quality targets by the end of the year. This was accomplished ahead of schedule and below budget despite numerous obstacles including the worst winter on record in the past 50 years for the area. What led to the success of the project, and in particular the commissioning phase of the project? This paper takes a high level look back and provides an overview of the methodology used, key issues encountered and lessons learned to answer this question.

Jan 1, 2015

By Robert Dickson

Princess colliery is operated by Old Sydney Collieries, Limited, a direct descendant of the General Mining Association of London, England, which, in the first quarter of the nineteenth century, pioneered in coal mining in Nova Scotia. The coal worked is a 5 ft. 6 in. seam known generally through the Sydney coalfield as the Harbour seam but referred to locally as the Sydney Main. Entry is made by shafts, 680 feet deep, sunk in 1871 on a headland forming the northern entrance to Sydney harbour. From them extend the main roadways of the colliery, a distance of 700 feet to the shore line and a further distance of 14,700 feet in submarine areas to a total length of 15,400 feet. It was the first colliery in Nova Scotia designed to work submarine areas. Lateral development extends across a frontage of 16,000 feet and the submarine area from which the coal has been extracted is slightly over 6 square miles. There yet remains sufficient territory ahead of the workings to assure a future life to this colliery estimated at over 80 years at the current rate of production. In this area the seam dips at 6 to 7 per cent and face workings have reached a depth of 1,690 feet below the sea level. Until 1923 extraction of the coal was by room-and-pillar, followed by the drawing of the pillars. At that date the superincumbent strata had reached a thickness of 1,400 feet, resulting in heavy weighting on the roof and severe side pressure on the coal ribs. In combination with a soft, heaving pavement this created a set of conditions involving great difficulties and expense in keeping open places driven in the solid sufficiently long to permit recovery of the coal in the pillars by methods and equipment then available. The operator was forced to resort to extraction by longwall as the only economical method of winning the coal.

Jan 1, 1948

By K. Dinh

The Ground Penetrating Radar (GPR) has been studied for a long time as a non-destructive evaluation (NDE) technology for inspection of concrete structures. Currently, the most widely used technique for interpreting GPR data of concrete bridge decks is the one that based on the amplitudes measured at various interfaces such as asphalt-concrete, top rebar, or slab bottom. The assumption behind this technique is that a sound concrete deck should have the same reflection amplitude at these interfaces while any low number would indicate some sign of deterioration. Unfortunately, this assumption is not completely valid in most cases. As a consequence, the reported test results usually do not reflect real condition of concrete bridge decks in question. The main goal of this paper is therefore twofold: (1) to discuss the limitations of the amplitude analysis method, and (2) to propose a new model that interprets GPR data of concrete bridge decks. The model methodology is based on the comparison of GPR A-scans between two inspections, using the so-called correlation analysis. The results, indicated by the correlation coefficients, are then employed to develop a contour map that estimates different levels of deterioration. The model is then implemented to a case study in order to illustrate its methodology.

Aug 1, 2013