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By J. T. Liu, G. H. Han, W. C. Chai, Y. F. Huang

"In beneficiation process, metal ions could adsorb onto clay mineral surfaces or interact with flotation chemicals, and then result in the flotation behavior changing of desired minerals. Al(III) is the dominating ion existing in the bauxite flotation system. In this research, the adsorption behaviors of Al(III) on two silicate clay minerals (including bentonite and kaolin) were investigated by means of UV-Vis spectra, zeta potential testing and scanning electron micrograph analysis. The adsorption experiment results show that the adsorption capacity of clays for Al(III) ions increases with the initial Al(III) concentration, contact time and solution pH. There are some different adsorption behaviours for two clays. Increasing the clay concentration decreases the adsorption capacity of bentonite, while increases first then decreases for kaolin. Higher temperature favours the adsorption of Al(III) on bentonite but goes against for kaolin. The adsorption capacities of bentonite and kaolin for Al(III) respectively reach 12.48 and 0.875 mg/g at initial solution pH 5. Zeta potential results show that the adsorption of Al(III) on two clays is characterized by electrostatic attraction mechanism.INTRODUCTIONIn beneficiation process, there is inevitably a wide variety of metal ions generated from mineral crushing, mineral dissolution and water chemistry conditions. Metal ions adsorb on the mineral surfaces or interact with the beneficiation agents, affecting the flotation efficiency of desired minerals (DiFeo et al., 2001; Parolis et al., 2008; Shackleton et al., 2012; Shengo et al., 2014). Therefore, it is necessary to have a detailed investigation on the adsorption behaviour of metal ions on clay minerals.Having good ion exchange capacity and negative surface charge, the clay minerals could take up various metal ions from the mineral-water system. Bentonite and kaolin are very common aluminosilicate clays in the mineral processing system. These two clays both hold a permanent negative charge, =X- on the basal surfaces, and a smaller variable charge, =SiOH on the mineral edges (Gu & Evans, 2008; (Gu et al., 2010). Adsorption experiments are usually used to study the adsorption affinity of metal ions for clay minerals (Sen & Bhattacharyya, 2012). The adsorption of Zn(II), Cu(II) and Pb(II) onto natural bentonite showed that the adsorption amounts of metal ions increase with contact time, solution pH and metal ion concentration, but decreases with adsorbent concentration and system temperature (Sen & Gomez, 2011; Melichova & Hromada, 2013). Cr(III) adsorption on bentonite was significantly pH dependent. The adsorption process followed pseudo-second-order model and the equilibrium adsorption was consistent with Freundlich isotherm (Lollino et al., 2015). The adsorption behaviours of Pb(II), Cd(II), Ni(II) and Cu(II) onto kaolin indicated that increasing pH favoured the adsorption of metal ions (Jiang et al., 2010). The adsorption of Cd(II), Cu(II), Pb(II) and Zn(II) onto kaolin showed that an ion-exchange reaction occurred at pH<7.0 and inner-sphere surface complexes were prone to form at higher pH (Srivastava et al., 2005)."

Jan 1, 2016

By X. Xu, J. K. -W. Wong, J. -Y. Delenne, K. Soga

Hydraulic fracturing (HF) is a mulit-scale and multi-physics process which makes numerical modelling challenging. Conventional numerical models focus on multi-physics nature of HF but the multiscale nature is compromised by idealization of reservoir to be continuous, homogeneous and isotropic. However, natural fractures take a significant role in the success of HF for exploration of unconventional resources like Shale gas. Advancement in microseismic monitoring provides useful data for simulation in a much greater details. There is an urgent need to develop a suitable numerical tool for multi-scale threedimensional simulation to better understand the roles of discontinuities and heterogeneity in reservoir and its interaction with HF, especially to address the environmental concerns such as induced seismicity. In this paper, a simple discontinuum numerical method – Lattice Element Method (LEM) is proposed to model HF in a large scale three-dimensional model. A reservoir is modelled as a lattice network composed of 1D Hookean’s spring. Fracturing is modelled simply by removing lattices that meet a specified threshold as determined by the critical energy release rate of the rock. By introducing disorder in the model, mesh dependency in modelling fracture growth is minimized. Fluid flow is simplified as flow in pipe network and the permeability of pipe is related to fracture aperture by cubic flow law. Therefore, fracture flow and rock deformation are fully coupled. In this paper, four simulations of the same configuration except with different degrees of reservoir heterogeneity are presented. Fractures formed are diffusive and two groups of fracture are identified – connected fractures and isolated fracture without clear spatial correlation. The former forms a ‘fracture cloud’ and contributes to fluid flow and modeled by pipe network. The flow of fluid is highly tortuous and pipe network is sparely connected. The degree of reservoir heterogeneity controls the growth of ‘fracture cloud’ and pipe network. Microseismic monitoring often shows diffusive fracturing during HF on site and hence the outcome of the proposed model can be compared to such monitoring results.

Jan 1, 2015

By P. Blonde

Recent analysis has suggested that a balanced recovery profile can improve flotation bank performance. Test work was conducted to test the balanced profile concept at the Penhorwood talc mine near Timmins, Ontario, Canada. Plant trials were devised to determine how to control the recovery profile and the resultant impact on grade and recovery in a rougher bank of four cells. Accompanying gas dispersion measurements revealed a maintenance issue with one cell that was corrected. By manipulating air and frother addition it was possible to bring the bank closer to a balanced recovery profile and the down-the-bank grade/recovery improved. Plant production showed an increased talc grade at similar yield with the balanced profile. The results provide justification for a long term plant trial.

Aug 1, 2013

By D. Jean Hutchinson, Mark Diederichs

"Cable bolts are an important support component in modern underground mines. If an optimized cable bolt system is to be achieved, it is insufficient to focus on cable bolt layout design or on cable bolt installation in isolation. Cable bolt support, like all engineered systems, requires a holistic approach, encompassing integrated elements of design, implementation and verification. The “Cable bolting Cycle” described in this paper incorporates these components along with related tools and procedures which should be used together to ensure effective and efficient cable bolt support.Design involves the consideration of demand, capacity and constraints as outlined in this paper. The demands imposed on the sup-port system by the rock mass response to excavation under the combined action of stress and gravity must be matched to the capacity of the cable bolt array. The cable bolt system capacity is a function of the component strengths of the steel strand and the bond (load transfer) and by the deformation response and retention characteristics of the system. The design is bounded by operational and economic constraints.Implementation of the cable bolt array can then proceed and must include appropriate protocols of communication, training and quality control, in addition to both general and site specific installation procedures. Implementation will be discussed as the sum of these components.Implementation of the cable bolt array can then proceed and must include appropriate protocols of communication, training and quality control, in addition to both general and site specific installation procedures. Implementation will be discussed as the sum of these components.The information presented in this paper represents a very abbreviated version of much broader concepts, procedures and design charts, presented in a practical cable bolting handbook by Hutchinson and Diederichs (1996)."

Jan 1, 1996

By D. Bois, P. Keating, J. Lemieux, M. A. Vallée, M. Allard, R. S. Smith, L. Z. Cheng, M. Chouteau, D. K. Fountain

"Abstract -A test survey using the MEGATEMII airborne electromagnetic system was flown over the Iso and New Insco massive sulfide orebodies in the Rouyn-Noranda mining camp, Canada. The results were compared with data from historical systems (INPUT, DIGHEM) used to discover the deposits. The historical data show that the two deposits have comparable conductances. However, the modern MEGATEMII system reveals that the New Insco deposit has a much slower decay than the Iso deposit, and it is, therefore, interpreted to be more conductive. The MEGATEMII anomaly maps provide estimates of the location, depth, dip, and strike of the two deposits, information that was not available from the historical anomaly maps. The signal-to-noise ratio of the MEGATEMII data is greater than the historical data, yielding more sharply defined anomalies. The investigations also included a comparison between 90 Hz and 30 Hz MEGATEMII data. The 90 Hz data were found to be useful for mapping the less conductive parts of the Iso body, whereas the 30 Hz data demonstrated that the New Insco body is more conductive. Analysis of height attenuation data over the Iso body indicates that the body could be seen by the MEGATEMII system if it were buried an additional 230 m deeper (in highly resistive material). On the other hand, the INPUT system would detect the Iso body only if it were buried no deeper than an additional 60 m. Tests with the transmitter turned off showed that, for this flight, the MEGATEMII system noise levels on the processed data are about 300 pT/s. Sommaire - Dans le cadre d’un projet de recherche, un ensemble de levés d’essais électromagnétiques aéroportés employant le système de MEGATEMII a été effectué au dessus des dépôts d’Iso et de New Insco, Rouyn-Noranda, Canada. Les données ont été comparées avec les réponses des systèmes qui ont découvert ces deux dépôts (INPUT et DIGHEM). Les données antérieures montrent que le dépôt d’Iso a une conductance comparable à celle de New Insco. Cependant, les données de MEGATEMII démontrent que le dépôt de New Insco a une haute valeur de la constante de décroissance, ce qui reflète une plus forte conductivité. La carte d’anomalies de MEGATEMII indique la localisation, la profondeur, le pendage et l’orientation des deux dépôts, ce que la carte d’anomalies antérieure ne montrait pas. Le rapport de signal à bruit de MEGATEMII est plus grand que celui des données de INPUT et de DIGHEM; de plus, les pics sont mieux définis. Les tests ont également permis une comparaison entre les fréquences de base de 90 Hz et de 30 Hz. Les données de 90 Hz se sont montrées utiles pour cartographier la partie du dépôt Iso dont la conductivité est la plus faible, tandis que les données de 30 Hz montrent clairement que le dépôt de New Insco est plus conducteur. Les analyses de l’atténuation du signal avec la hauteur ont indiqué que le dépôt d’Iso pourrait être détecté par le système MEGATEMII s’il était enfoui à 230 m sous la surface (dans un milieu hautement résistant). D’autre part, le système INPUT pourrait seulement détecter le dépôt d’Iso s’l était situé à 60 m de profondeur. Les tests avec l’émetteur fermé démontrent que le niveau de bruit est des l’ordre de ±300 pT/s."

Jan 1, 2006

By Laszlo Imreh, Pierre Trudel, André C. Tessier

"The Siscoe gold mine is ranked as the fourth largest mine in the history of the Val d' Or mining district with a total production of 27.4 tAufrom1929 to 1949. Most of the gold mineralization occurred in quartz veins, hosted in a small (.69 km2) intrusion of altered quartz gabbro known as the Siscoe stock. The southern contact of the Siscoe stock is crosscut by a major shear zone (the ""K"" zone) trending 295/80 NE and from which gold mineralization was also exploited within the limits of the stock. Field and petrographic observations of the Siscoe stock combined with chemical analyses of major, trace and rare earth elements of the stock and its volcanic host rocks (Dubuisson Formation) suggest that:The Siscoe stock comprises four alteration facies formed from a homogeneous precursor: 1) the actinolite - Mg-chlorite facies, characterized by low FeOt,Na2O andTiO2 , and highAlp3 and MgO; 2) the albite- Fe-chlorite facies, containing high concentrations of FeOt and Nap; 3) the Mg + Fe-chloritefacies, which is transitional between the actinolite- Mg-chlorite and albite- Fe-chloritefacies; 4) the carbonate-chlorite facies, which consists of rocks that were subjected to extreme hydrothermal alteration, is spatially associated with mineralized veins and part of the K-zone. The first three facies are depleted in SiO 2, CaO and Au, and enriched in MgO, relative to fresh rocks of the Siscoe stock and the equivalent rocks of the Dubuisson Formation.Hydrothermal fluids introduced mainly along the K-zone ""channelway"" induced three types of element remobilization, resulting in the various alteration facies: 1) redistribution of elements within the stock from one facies to another (e .g., FeOt, Nap, Ti02 migrated from the actinolite- Mg-chlorite facies to the albite- F e-chlorite and Mg + Fe-chlorite facies); 2) remobilization of elements from the intrusive rocks into veins (e.g ., SiO 2 and CaO ); 3) introduction of elements by hydrothermal fluids in rocks of the Siscoe stock (e .g., Al2O3, MgO, H2O, CO2 and FeOt).The Siscoe stock and the Dubuisson Formation form part of the same tholeiitic suite. Similarly, the Bourlamaque batholith and the Val d'Or Formation belong to a single calc-alkaline suite. In view of this relationship, dissimilarities between the petrochemistry of the Siscoe stock and the Bourlamaque batholith suggest that the two intrusions are not co-magmatic.Finally, gold may have been leached from rocks of the Siscoe stock and remobilized into the quartz-carbonate mineralized veins. In order to account for the total production at the Siscoe mine, approximately 1.2 km3 of the Siscoe stock is thought to have been partially leached of its gold."

Jan 1, 1990

By C. Gravel, A. Fathi, P. Rivard, G. Ballivy, Z. Moradian, M. Quirion

Knowing shear mechanism of discontinuities under monotonic and cyclic loading conditions is a key factor in stability analysis of rock slopes and rock foundations. In this paper, the effect of cyclic loads on the shear mechanism of joint asperities is described. For this purpose, a fresh tension-split joint from a granite block was used as a reference and thirty five mortar replicas were fabricated. Cyclic shear tests were conducted on replicas under low values of constant normal load (CNL) using a servo-controlled loading system. Tests were performed in two consecutive steps; load-controlled and then displacementcontrolled. In the load controlled part, after initial increase of shear stress to 0.25 MPa, the test was stopped for 2 minutes, then increased to 0.5 MPa, and finally decreased to 0.25 MPa. This process was repeated ten times. At the end, the test was continued up to 10 mm shear displacement under displacement-controlled loading in order to pass the peak shear strength and reach the residual strength. Characterizing joint surface and modeling of involved asperities during the tests was undertaken using a Matlab code developed with new mathematical expressions. The algorithm used in the code is based on three-dimensional coordinates of the scanned joints’ surfaces before and after the test. It was found that a high percentage of degradation happens during the first cycle of loading and during the other cycles, degradation occurs gradually. While comparing tests conducted in monotonic and cyclic loading conditions, it was observed that under low number of cycles, the pronounced mechanism is consolidation of the joint surfaces. This consolidation increases contact areas and, therefore, shear strength parameters.

Jan 1, 2015

By R. W. Diamond

PUBLIC debts, and the policies guiding public finance in Canada today, are in such a state that every intelligent citizen should be familiar with them, and should be concerned about them. None of you have robe reminded that taxes have already risen to a point where they both annoy and hurt you, but they should also alarm you; alarm you, not so much because of the taxation, but because of the mounting expenditures represented by that taxation. I have no hesitation, therefore, in presenting a paper dealing with public finance at a meeting of the Mining Institute, since all present are concerned,. both as individuals and as representatives of the industry. Moreover, it is important that engineers, particularly, should become better acquainted with the interlocking relationships of economics, public finance, government, and technology. While I am neither an economist, a tax expert, nor a chartered accountant, I shall try to tell you, from my viewpoint as an engineer and an interested voter, the story of public finance in Canada today and of certain causes and effects, and I shall venture certain conclusions. In doing so I may merit criticism by experts, but I will risk this in the hope that sufficient interest will be stimulated in the subject to persuade you, as individuals and as groups, to advance, or to institute, your own studies in public finance, and in turn to interest others. I hope that some of the ideas which will be expressed, or which may develop, will bear fruit. I fully realize that several eminently qualified men have spoken on this subject during recent months, and that many authoritative articles have been written. However, I approach it with confidence, because I propose speaking to you not as an authority, bur as one of you, having similar interests and similar engineering knowledge, who only a few months ago became particularly interested in the subject, studied it, and who now sets before you a summary of his findings, with the conviction that the situation is so serious that constructive planning and constructive action by all thinking citizens are imperative.

Jan 1, 1939

By N. Shi, T. G. Joseph

ABSTRACT: An interactive cable shovel simulation has been developed to mimic any shovel dipper geometry for a given cable shovel operating in any homogeneous face material. This interactive cable allows the user to predict shovel performance in any face material encountered and track both its ground stability and the dipper-ground interaction. An embedded Microsoft® Visual Basic spreadsheet was used as the platform for developing an interactive simulation that allows for maximum user-defined parameter input and interactive visual output. The result is an analytical dipper-ground interaction solution that yields crowd, hoist, and digging effort as a function of face activity position.

Jan 1, 2011

By S. W. Marcuson, P. J. Mackey

The 1973 Oil Embargo and succeeding disruptions in supply had a profound effect on energy costs and consumption patterns in the developed world. This was especially true in the USA where post World War II growth, fueled by low-cost imported oil, left the country dependent on uninterrupted oil shipments from the volatile Middle East. In this atmosphere, Professor H.H. Kellogg of Columbia University, convinced of the necessity of good environmental stewardship by the writings of the era’s leading environmentalists, developed a methodology for evaluating energy and process efficiency of metallurgical processes and wrote a series of papers describing and applying the techniques. One of these, "Energy Use in Sulfide Smelting of Copper" is recognized as a seminal work which both described the state of energy usage in copper smelting in the mid-1970’s and portended future developments. The background to these papers is examined and the current and past Cu-Ni matte smelting practices in Canada are examined in the context of the results. Data from early 20th century publications describing reverberatory and blast furnace operation is employed to show that energy consumption for much of the century was several multiples higher than that calculated for best reverberatory operation in the 1970’s.

Jan 1, 2015

By Henry F. Hebley

THE solid fuel industry, especially that branch represented by bituminous coal, is gradually becoming aware of its ? paramount importance in a world where there is an ever increasing demand for the products of a mechanical age. In practically every process of manufacture, the necessity for energy in some form is being multiplied. Some of that prime energy is derived from water power-hydro-electric schemes, flood control schemes, etc. - but often the electrical energy thus developed is generated at great distances from the load centres, requiring long transmission lines with consequent transformer and transmission losses. A few plants have harnessed the tidal power of the seas and one has harnessed the energy of the wind in a modern manner. All of these schemes are dependent on certain natural geographical, hydrographical, and physical advantages of terrain, as well as an adequate area of consumption of the energy developed. If flood control is the primary object, then power generation is a by-product; and the economics of large capital expenditure on power generating equipment must be considered in that light.

Jan 1, 1945

By W. C. Whittaker

Introduction When one thinks of a coal stripping deposit, the picture that usually comes to mind is that of a more or less flat seam from two to twenty feet in thickness overlain by ten to fifty feet of overburden, in suitable ratio for economic operation. This is the usual type of stripping deposit and is quite a common occurrence in various parts of the prairie provinces. Rather unusual types of coal stripping deposits are being presently worked as open-cut mines by Sterling Collieries, Limited, and the Co al Valley Mining Company, Limited, at Miles 47 and 48 on the Alberta Coal Branch, some 150 miles south west of Edmonton. These deposits are of interest chiefly because they represent turned-up and greatly thickened sections of the Mynheer seam, and as such they present their own problems, peculiar to the commercial exploitation of a seam of this type. The area in which these deposits occur was originally owned by the Pacific Pass Collieries, whose operations, however, were confined to under-ground mining at Lovett, some eight miles to the southeast. It was not until l918 that the value of these deposits was realized, when the Company now known as Sterling Collieries, Limited, opened their pit at Mile 47. At the inception of the work, coal was loaded directly into the railway cars by men using wheelbarrows. In 1920, a tipple was built, after which the coal was loaded by steam shovel into mine cars, hauled by steam dinkeys, and loaded over the tipple into railway cars. In 1922, the Coal Valley Mining Company entered the field at Mile 48, with an entirely mechanical equipment, and at the present rime these two are the only stripping properties in Alberta using mechanical equipment both for the removal of overburden and the loading of the coal. These Companies have operated continuously since that time, and have to date mined and shipped 4,000,000 tons of coal, and moved some 5,255,000 cubic yards of stripping. The present annual coal output for the two mines is about 240,000 tons.

Jan 1, 1935

By A. Demers, M. Chapman, N. Reynier, R. Lastra, M. Courchesne, C. Laviolette

Historic medical isotope production at Canadian Nuclear Laboratories (CNL) in Chalk River involved the dissolution of irradiated isotope targets prior to extraction of Mo-99. This process generated liquid waste that was cemented in 5-gallon containers and transferred to an outdoor waste-management facility for intermediate storage. Research was undertaken to develop an innovative method for uranium, mercury and cesium recovery from the radioactive cemented waste (RCW). Regulations prohibit the removal of active radioactive waste from the Chalk River facility. Thus, CanmetMINING produced surrogate material following the same procedures and conditions to those used at CNL. The selective recovery of the uranium from the surrogate radioactive cemented waste (SRCW) could offer CNL more disposition options for the resulting wastes. Leaching tests were performed using four different SRCW at 1 kg scale. Different conditions, operating parameters, and the presence of plastic and corrosion products were evaluated on solubilization. The research investigated the use of potassium iodide with the sulphuric acid leach to increase metals recovery. Iodine improves the solubilisation of metals and the U dissolution reached 99%. The increase of leaching time reduces the U solubilization due to silica gel formation. Therefore, it will be important to control leaching time to avoid the loss of U during the pilot scale experiments. For Hg, the solubilization ranged from 60 to 80% due to the presence of metallic mercury and mercury sulphide found in SRCW cured at 60°C and/or aged for 30 months. Ion exchange (IX) was found the best method to separate the uranium from the impurities and produce a purified and concentrated uranium solution suitable for yielding a uranium product (yellow cake).

Jan 1, 2020

By T. Xue, A. Singhal, D. Wrana, I. Mihaylov

"At Vale's Thompson Nickel Refinery, the copper and arsenic in the nickel electrolyte are removed by precipitation using H2S, generating a sulphide precipitate containing about 40% Cu, 8% Ni, 2 to 4% As and 30% S. This residue has been typically stored in impoundment ponds within the plant site. Various options for reprocessing it have been investigated over the years. One of the options involved oxidative pressure acid leach, whereby over 95% Cu, Ni and As were extracted. More recently, an atmospheric alkaline sulphide leaching process for selective removal of 70 to 90% As was developed and mini-plant tested. After alkaline sulphide leaching, the dissolved arsenic is precipitated as stable basic ferric arsenate (BFA) with the addition of ferric sulfate, while the low-arsenic Cu/Ni sulfide is suitable for processing in Vale's operations elsewhere in Canada.INTRODUCTIONVale’s Thompson Nickel Refinery was commissioned in 1961 and currently it has the capacity to produce about 56,700 tonnes per year of electrolytic nickel as cathode slab and rounds products. A sulphate and chloride mixed electrolyte is used in the Thompson refining process and it typically contains 75 to 85 g/L Ni, 50 to 60 g/L Cl, 90 to 120 g/L SO4 2-, 25 to 30 g/L Na and 8 to 9 g/L boric acid. The main impurities in the Thompson anolyte are copper, cobalt, arsenic, iron and lead.The simplified Thompson electrolyte purification flowsheet is shown in Figure 1 (Oliver & Wrana, 2009, Goble & Chapman, 1986); it consists of precipitation of copper, arsenic and lead with H2S, followed by nickel replenishment with ground matte and acid and removal of cobalt and iron with Cl2 and NiCO3."

Jan 1, 2012

By William M. (Bill) Shaver

"The author will review the early history of shaft sinking as well as focus on the improvements made in shaft design and construction over the last fifty years (1970 to 2019) to predict how shaft sinking will change over the next fifty years and describe what the shaft sinking world might look like in 2070. INTRODUCTION It is a great honour to be one of your keynote speakers for the Fourth International Conference on Shaft Design and Construction being held in Toronto in November 2019. This is one of the opportunities we have to thank the Mining Companies of the world as well as the industries and companies we serve for their support of the mining contracting and shaft sinking business of Canada and the world at large. Many of these companies are represented here today. Without your support many of the innovations we will talk about today would not be possible. We would also like to thank all the companies that work with us in our business including all the contractors and suppliers who provide the various services we require. These include equipment manufacturers, engineering companies, project management companies and suppliers large and small who cater to our every need as quickly as possible. Without all these partners we would not be as good as we are. Many of these companies are our sponsors this week. Thank you from all of us! This is also an appropriate time to pause and think about those Shaft Sinkers we have lost and those who have been injured on our projects around the world. Please bow your head and remember the Shaft Sinkers you have worked with, who did not return home or those who returned home injured. Think about how we can continue the work of making shafts safer every day as we go forward with our projects so everyone goes home to their families safe and sound. Pause for a minute and thank you. The subject matter we have chosen to discuss today is “Shaft Sinking in the Next Five Decades”. How will the work be done, how fast will it be done, what will it cost, and why we think this may occur? It is appropriate to consider this over the next few days with this auspicious group we have assembled. Today, we will look back at all the advances that have been made over the last many years and look ahead to the future to attempt to predict what shaft sinking will look like in 2070. When I look around the room I recognize that many of us will not be around then so we need not worry about being wrong. Suffice it to say that the next 50 years will be very interesting and exciting for the shaft sinking business."

Jan 1, 2019

By S. Hopkins, R. Preston, S. Gillis

"This paper examines typical visual inspections of operational soft rock mine shafts and discusses some of the challenges involved, many of which are associated with inconsistent inspection practices. The paper presents the development of a more standardized approach to periodic shaft inspections that supplement the more frequent inspections performed by shaft crews at the mine. This approach helps to keep an accurate record of changing conditions, compare conditions between multiple mine sites, as well as prioritize and plan potential remedial work. INTRODUCTION Shaft inspections, whether they are performed daily or weekly by members of the shaft crew at the mine, or periodically by consultants, traditionally involve a visual inspection undertaken with personnel traveling on an inspection deck on the conveyance, taking notes and photos. Inspections are typically required by mining regulations and carried out to identify and address hazards before a safety incident occurs that could cause harm to people or damage to property, as well as to help plan required maintenance work. Depending on the site, there can be many challenges associated with inspections in the shaft, especially compared to a typical inspection at surface. Some of these challenges are associated with the shaft environment itself, while others are related to the subjectivity of inspections and a lack of standardization, particularly between multiple sites within the same operating company. Recognizing these challenges, a more consistent and repeatable approach to shaft inspections in soft rock mines is evolving. This approach involves reviewing available historical data, comparing sites with similar conditions, establishing survey control, documenting observations and measurements with locations, and updating as-built or condition drawings. Part of this standardized approach is the implementation of an innovative 360-degree camera with a high-power lighting system that can be used either remotely or alongside personnel completing a traditional visual inspection. The system uses six cameras to take photos at a rate of 15 frames per second, with the image data subsequently processed and stitched, then joined into a high-resolution video. This tool improves time-efficiency, objectivity, and repeatability of inspections."

Jan 1, 2019

By D. Van Tonder

ABSTRACT The comparative economics of ion exchange and direct precipitation have been analyzed by developing indicative CAPEX/OPEX models for typical alkaline leach uranium circuits. An agitated tank ore leach application is considered, comparing resin-in-pulp and direct precipitation as recovery options. Capital and operating cost estimates are derived from rates and factors used in recent studies and projects. The analysis showed the main economic drivers to be the ore grade and resin loading. The resin loading is impacted by the prevalence of competing ions, especially chloride. At resin-in-pulp solution chloride concentrations below 3 g/L and uranium grade below 640 g/t U3O8, resin-in-pulp is more economical, whereas at chloride concentrations above 3 g/L, direct precipitation is more economical.

Jan 1, 2012

By A. G. Ballachey

Introduction This paper will describe the mining plant and underground operations at Quemont. Details of geology and milling are beyond its scope. Papers on these subjects will be prepared and presented separately. A detailed account of the exploration and development, 1944 to 1947, has been given by W. L. Brown (1). Location The mining concessions of Quemont Mining Corporation, Limited, are in Rouyn township, Rouyn-Noranda county, northwestern Quebec. These concessions total about 640 acres in area. They lie within the limits of the City of Noranda, contiguous to, and directly north of, the Horne mine of Noranda Mines, Limited. A large area in the southern part of the property is covered by the north arm of Osisko lake. Production The present operating rate is about 2,100 tons per day. Three flotation concentrates are produced: copper, containing a large proportion of the gold and silver in the ore; zinc; and pyrite, which carries an appreciable additional proportion of gold. The copper and zinc concentrates are shipped to smelters as produced. The pyrite concentrate is cyanided to recover additional gold, after which it is filtered, dried, and shipped for the manufacture of sulphuric acid. The principal revenue metals are copper, gold, and zinc. Silver and pyrite are important by-products.

Jan 1, 1952

By Rob Boom, Yasuyuki Tozaki, Frank M. Wheeler

Selection of a suitable site for a metallurgical plant is crucial for the success of the business case. For a brownfield project, with the decision to locate the project on a site with existing production facilities and activities, the selection of the site has been made. For a greenfield project, important economic and logistical considerations include proximity to primary and secondary resources and/or to the market, infrastructure, and access to energy and water. National and regional aspects, including the social license to operate, can be decisive in final site selection. Key to recruiting and retaining a labour force are proximity to urban areas, along with weather and health conditions at the site. Risk factors include site geotechnical parameters and topography, contamination, as well as probability and types of potential natural disasters.

Jan 1, 2015

By W. J. Wright

Summary Statement The following notes on the geology of the Grand Lake coalfield are intended to be introductory to a second paper being read at this meeting, which paper will describe the earlier and the more modern mining methods. The coal industry of the Grand Lake coalfield is centred chiefly within a three-mile radius of Minto, but minor operations are dotted over an area of approximately 50 square miles extending easterly to the vicinity of Chipman and Coal Creek (see Figure 1). The coal comes from one seam of Pennsylvanian age. The seam varies in thickness from 16 to 30 inches and lies almost horizontal at depths of 0 to 125 feet. It has been mined and prospected over an area of approximately 150 square miles, but in a portion of this area the commercial possibilities have been destroyed by erosion. The industry is the oldest of its kind in North America, but it did not at tract particular publicity until about 1914. Since that date, mining methods have improved and the output has rapidly increased until, in 1934, it amounted to 271,335 long tons, and furnished employment for about 1,000 men (1). Approximately 73 percent of this amount was produced by the Minto Coal Company, the Miramichi Lumber Company, the Avon Coal Company, and Welton and Henderson, and 25 per cent by the Rothwell Coal Company, Harvey Welton Limited, G. H. King, the Reade Construction Company, and the Newcastle Coal Company. The remainder was produced by J. W. Carter, G. D. Crossman, T. H. Swift, C. S. Yeamans, and several other small operators. The coal is won by underground mining, except in the case of the Reade Construction Company, and a minor operation by Ashfield and Pieton, who have employed open stripping. It is mined only as required to fill definite orders, and is loaded directly into cars for shipment. In 1934, the larger mines did not operate full time, and the production could easily have been increased if markets had been available. The coal is sold in four grades: screened or lump, run of mine, slack, and stripping. The chief market is with the railways and commercial plants, with a fair amount for domestic purposes.

Jan 1, 1935