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By Douglas A. Karvonen

"Competition in the world potash market has increased significantly since the late 1970s. The failure of consumption to grow at expected levels has led to industry over-capacity, a situation which is likely to persist at least until 1990. Individual Saskatchewan producers and their offshore marketing company, Canpotex, have responded to this challenge by increasing mining efficiency, developing more cost-effective and reliable transportation systems and establishing innovative financing and market development programs tailored to customers' special needs. Investment in warehouse facilities to serve U.S. customers and exploration of opportunities for intermodal distribution through the Great Lakes and the Mississippi River system have maintained individual producers' position in the highly competitive domestic market.Export sales through Canpotex have been bolstered by utilization of CIDA funds, Exp ort Development Corporation financing guarantees and other innovative payment plans which enable heavily indebted developing countries to maintain the import levels which are necessary for their agricultural development.IntroductionPotash is the general term applied to various potassium salts both natural occurring and commercially derived. The most common of the commercial product s are potassium chloride, potassium sulphate and potassium magnesium sulphate. The potassium content of potash is measured in units of K20 equivalent. The common grades of potassium chloride produced for agriculture average at least 60 0/0 K20 compared with approximately 50% Kp for potassium sulphate and 22% for potassium magnesium sulphate."

Jan 1, 1985

By T. Kho, W. Zhang, M. E. Reed

The control of flash furnace heat balances is critical. Suspension smelting control and stability comes from stable operation of the heat balance, and this leads to a stable reaction shaft exit temperature. A number of flash furnace operations have been reviewed to determine if the application of this approach is beneficial for their operation. The cause and effect relationship between reaction shaft exit temperature with uptake and throat buildup is being enhanced with this work program. Our operating personnel are exposed to the operational hazards of cleaning this buildup from the throat and it is imperative that as an industry we continue to look for repeatable solutions. WorleyParsons has reviewed operational data from a number of flash furnaces and looked at the possible improvements that can be made to decrease variation in the reaction shaft exit temperature. The data assessed for each operation illustrate the need to fully understand the process inputs to the particular operation and to ensure that the control changes are correctly impacted. In the plant data that have been assessed for a number of operations combinations of feed changes and inappropriate process decisions have lead to changes in reaction shaft exit temperature which impact the overall furnace operation and the uptake shaft condition, and ultimately the boiler. INTRODUCTION In 2016 WorleyParsons jointly prepared a paper outlining the effects of heat balance control on the Olympic Dam flash furnace (Reed et al, 2016). That paper investigated the importance of heat balance control in flash furnaces and demonstrated the changes made at the Olympic Dam operation to control the heat balance in the furnace and the impact that change had. The operation is still using the tool to assist in trouble shooting performance and pinpointing problems that may lead to issues in the furnace throat and Waste Heat Boiler (WHB). As a result of the interest in the methodology and due to the issues surrounding safety and process performance caused by WHB throat buildup and damage, WorleyParsons approached a number of flash furnace operators to discuss the application of the approach at their operations.

Jan 1, 2019

By D. Moffat

Rio Algom Limited has mined uranium at Elliot Lake, Ontario for 20 years. The production of this energy-generating element results in the need to dispose of low-level radioactive solid wastes and liquid effluents. Because of the wet-temperate climate at Elliot Lake, the liquid effluents are of particular importance. Radium-226 is the isotope which requires most attention, and the current practice for its control is by addition of barium chloride and retention of the resultant precipitates in large settling ponds. Analyses of typical effluents and waste streams are discussed and typical levels of radium-226, thorium-230, thorium-232, thorium-228, lead-2iO, polonium-2iO, and uranium isotopes are presented.

Jan 1, 1979

By J. Lee, K. B. Min, J. Rutqvist

Shear slip of fractures in fractured rock masses is a critical issue for many geological engineering applications, such as the design of underground nuclear waste repositories, enhanced geothermal systems (EGS), and geosequestration of CO2. This paper presents new development of the TOUGH-UDEC simulator for analysis of coupled thermal-hydraulic-mechanical (THM) processes in fractured porous media. As an alternative to developing a single coupled THM code in discontinuum, two existing wellestablished codes, namely TOUGH2 and UDEC, are coupled to cover coupled THM analysis of multiphase fluid flow, heat transfer, and deformation in fractured porous media. TOUGH2 is widely used for modeling heat transfer and multiphase, multicomponent fluid flow, and UDEC is a well-known discrete element code for rock mechanics, which have been verified and used by many groups all over the world. Although a sequential coupling of two codes is less efficient than having a single code in principal, a big advantage with coupling of TOUGH2 and UDEC is that both codes are well tested and widely applied in their respective fields. When linking two codes, the coupled equations cannot be solved simultaneously; they should be solved sequentially, with coupling parameters passed to each equation at specific intervals. After solving thermal-hydraulic equations through the TOUGH2 model, pressure (P) and temperature (T) information is delivered to UDEC model. Pressure information is directly stored at the center of each UDEC zone and domain, however, temperature information is interpolated from zone-centers to the corners nodes. After solving the mechanical equation through the UDEC model—considering new pressure and temperature—calculated fracture apertures are converted to equivalent permeability and porosity for TOUGH2 flow analysis. The solution was calculated by iteratively following an explicit sequence for numerical efficiency. Verification examples are presented to demonstrate the capabilities of the coupled TOUGH-UDEC simulator.

Jan 1, 2015

By Suzanne Paradis

Geographic distribution ? Deposit economics ? Temporal distribution ? Tectonic settings ? Basin architecture ? Morphology ? Ore-fluid chemistries Key exploration criteria

May 1, 2006

By Yu. V. Ponomarenko, A. I. Meka, P. A. Witherspoon, Yu. I. Volkov, J. E. Gale

"The mining of iron ore in the Kursk Magnetic Anomaly (KMA) region of the U.S.S.R. is done mostly by the open-cut method. An assembly of open pits capable of producing about 100 million tons of ore per year makes KMA the largest iron ore field in the world. Three gigantic open pits are currently in operation: Lebedinsky, Mikhailovsky and Stoilensky. These pits are as large as 13 km2 on the surface and as deep as 230 m. The mining operations are constantly faced with the problem of flooding from aquifers that overlie the orebodies; the magnitude of the problem is evident from the fact that the present groundwater inflow to these three pits is about 110 million mt /yr.Under such conditions, safe operations and pit wall stability are of great importance, and this has been accomplished very effectively by the appropriate use of seepage barriers and drainage systems. At KMA, the most important items used in the system of groundwater control are standard pumping wells, raise wells that drain into a 20 km to 30 km long underground drift located just outside the perimeter of the pit, horizontal wells driven through the pit walls, and horizontal drains. This paper describes the mining and engineering technology that have been developed at KMA to control the groundwater systems and protect the mines from flooding."

Jan 1, 1992

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 F. Kitzinger

Electromagnetic testing of wire rope has become more and more reliable over the past two decades. This improvement is partly a result of an unprecedented progress of electronic technology, which permitted the development of a new breed of testing instruments. There are two basic methods for the electromagnetic testing of wire ropes, the AC method and the DC method. Both methods rely on magnetic field disturbance caused by mechanical anomalies in the rope structure. The wire rope under test is passed through a magnetic excitation field, which can be a weak alternating field or a strong static field. Because the alternating field is produced by an alternating current, these instruments are of the AC type(l). In the early days of ND-testing, strong permanent magnets were not yet available; therefore, the static magnetic field was produced electromagnetically with direct current. Instruments based on static excitation are still called DC instruments(2), even though the field is now produced by a permanent magnet. Both these methods have certain characteristic features. The AC method can detect loss of metallic area caused by corrosion or other effects, whereas localized faults such as broken wires are better detected by the DC instruments . The basic principles of the wire rope testers have remained unchanged over the years and the improvements present in the new instruments usually reside in the signal processing and recording sections. The Instrumentation Department of the Noranda Research Centre* has been involved in a four-year development program which resulted in a new type of wire rope tester, the Magnographv** . This new instrument in many ways represents a considerable departure from the traditional wire rope testers. The Magnograph has already been patented in Canada and the U.S.A.(3), and patent applications are pending in other countries.

Jan 1, 1979

By Scott Rosenthal

?EMESRT History ?Design Philosophies (DP?s) ?Industry Successes ?Participation Thinking Differently Earth Moving Equipment Safety Round Table ? Use a critical mass to influence Marketing ? Define ?Problems?not ?Solutions? ? Leave the OEM designers to develop solutions Work within the companies to improve purchasing

May 1, 2010

By Georges Houlachi, Raynald Labrecque, Jean-Noël Cloutier

"Electrodialysis (ED) is an electro-membrane technology based on electrochemical process using electrical energy for the production of chemicals. The process can be used for concentrating, extracting, separating products, modifying molecules, purifying solutions, pH adjustment and regenerating salts into their base and acid. This paper reviews the principle of ED, present some of the different options and discuss applications that are relevant to the hydrometallurgy and mining industries for the treatment of effluents focusing on recovery of chemicals (acid and metals) and recycling of water minimizing the environmental footprint.INTRODUCTIONElectrodialysis (ED) is usually defined as an electrochemical separation process in which electrically charged membranes and an electrical potential difference are used to separate ionic species from an aqueous solution and other uncharged components [1]. ED technology consists of an electro-membrane technology based on an electrochemical process using electrical energy for the production of chemicals. It is a method combining electrolysis and dialysis was proposed for the first time in 1890 by Maigrot and Sabates [2]. In the late 1930s Teorell, Meyer and Sievers discussed membrane phenomena, revealed membrane potential, electric conductivity, transport number [3]. Meyers and Strauss introduced a multi-compartment ED apparatus consisting of two electrodes and a stack of ion-exchange membranes between them [1]. They succeeded to double the concentration of a KCL solution [3- Tarleton]. In general, ED consumes less energy than electrolysis to perform salt splitting. In that regard, one can expect an energy reduction of about 30% [4–5]. ED offers a great versatility in the domain of separation processes. Indeed, it can be used for concentrating, extracting, separating products, purifying by desalination, pH adjustment and regenerating a salt to acid and base components. This paper reviews the principle of ED, presents various options available and discusses potential applications relevant to the mining and metallurgy industries with economics of some successful industrial applications."

Jan 1, 2016

By J. E. Hawley

"The property of Francoeur Gold Mines, Limited, lies directly west of the Armfield mine in Beauchastel township, Abitibi district, and 12 miles west and slightly south of Noranda. The gold deposits are of particular interest because of their replacement character and close association with fault zones. The property was originally staked in 1923 following the discovery oi a mineralized zone near the eastern boundary. This became No. 1 orebody. Later discoveries in 1936 of No. 2 and No. 3 orebodies led to underground development and actual mining in July, 1938. A fourth orebody, No. 8, was found in 1939.The following is the production record up to December 31st, 1947:Beginning in September, 1944, ore was shipped to Noranda as siliceous flux, but late in 1946 milling of low-silica ore from No. 1 orebody was undertaken until operations were temporarily suspended in 1947.The four main ore deposits, Nos. 1, 2, 3, and 8, consist of siliceous ferrocarbonate and albite replacement bodies mineralized with fine pyrite and specularite in schistose fault zones in Keewatin volcanics. Barren to low grade quartz veins though present in some are uncommon, but small stringers of quartz are usually present wherever here and there visible gold is found. Nos. 1, 2, and 3 deposits lie in a major fault zone that extends completely across the property from west to east (over 7,000 feet) and dips N.40° to 50°, and are separated by intervals of 1,800 to 2,000 feet respectively. The fourth lies in a smaller fault zone striking east and dipping on the average 65°S.No. 1 orebody has been explored by mining to a depth of 500 feet, No. 2 to 400 feet, and No. 3 to slightly less than 300 feet . The greater part of No. 8 lies above a depth of 200 feet, but a raise has recently .been driven through from the west end of the 5th level of No. 1 to the 2nd level on No. 8 zone. Most of the ore of No. 8 zone above the 2nd level and of Nos. 2 and 3 above the 3rd levels has been removed."

Jan 1, 1954

By A. J. Neale, B. C. Flintoff

"A review of the dynamic rod mill-ball mill grinding circuit simulator developed at the University of Alberta, highlighting the modular structure and open-ended design, demonstrates the ease with which classical feedback control strategies can be designed and implemented. Various open loop simulations are presented to demonstrate the highly interactive nature of the grinding circuit and to indicate where potential control problems may be encountered. Closed loop simulations are examined, beginning with the basic SISO classical feedback control of circuit product size. Further improvement in the grinding circuit performance in the presence of various disturbances is realized through the application of a classical MIMO feedback controller. As an example of advanced (multivariable) control, static decoupling is implemented and shown to provide additional improvement in overall circuit performance.INTRODUCTIONIt has long been recognized in the processing industries that a dynamic process simulator is an indispensable tool in the design and evaluation of automatic control schemes. In mineral processing the lack of these simulators is felt to have been a major hindrance to the widespread implementation of effective process control systems. In particular dynamic simulation is a necessary precursor to any study of modern (as opposed to classical) process control methods. This paper discusses the development of a dynamic simulator that can be used to study various feedback control strategies. The simulation software provides a powerful educational tool for those individuals interested in grinding circuit control."

Jan 1, 1988

"Decreasing gold-in-ore grades is one of the main drivers of poorer productivity and rapidly escalating unit costs. Grinding costs, water use and reagent consumption are all intimately related to the ore grade processed. Various pre-concentration technologies have been developed that can be applied at various stages of crushing prior to ore grinding. This paper will review the amenability of ores to coarse particle barren gangue rejection for fine crush sizes in the pumpable particle size range (i.e., particles between 5 mm and 0.3 mm in size). The liberation of oxide gangue achieved during crushing is evaluated by proxy using sink-float analysis and the deportments of gold, sulfur, and arsenic into sinks and floats are monitored. Amenability of gangue rejection by continuous gravity separation is evaluated after various crushing modes (vertical shaft impact crushing, cone crushing, and HPGR crushing). The potential to identify coarse particle mineral association and liberation using three-dimensional x-ray computed tomography will be discussed.INTRODUCTIONThe aim of research in this area is to explore some of the attributes which make some ores amenable to preconcentration, or rejection of a significant component of the feed mass to tailings at a coarse liberation size. Characteristics such as ore type, mineralogy, breakage pattern, particle shape, and liberation characteristics may need to be examined to identify amenability to pre-concentration amenability.It is intended to focus on continuous gangue rejection in the pumpable size range (0.3–5.0 mm) as this remains one of the key opportunities to reduce processing costs through a combination of techniques including screening (for mineral differentiation rather than size classification only) and gravity separation (using jigs). This is to be contrasted to conventional preconcentration as performed with automatic ore sorters."

Jan 1, 2016

By Jaime V. Ongpin

"The author will give a capsule history of Benguet Corporation and attempt to identify its operating environment and underlying ""strategy"" until 1974, when the company's management assumed office. The company's operating environment and ""interim strategy"" from 1975 to 1980 will be described. The discussion will cover an environmental forecast and define the company's"" strategy for survival"" for the balance of this century.IntroductionIn December last year, I was asked to deliver a pa per for the management lecture series a t the Asian Institute of Management in Manila. The paper was entitled "" The 1970's: A Decade of Disaster For New Mining Projects"" . In that paper, it was my task to review the results of new mining projects in the Philippines during the previous decade. The task was not a happy one, for the results themselves were not only unhappy, but disastrous on a scale unprecedented in Philippine history. Out of a total of 17 major mining project s involving an aggregate capital investment in excess o f US $2 billion during the 1970s, only three project s have been profitable, and all the rest have either gone "" belly up"" or are teetering on the very edge of financial disaster.It is in the context of this shocking record of widespread financial dislocation in the Philippine mining industry, (which in varying degrees appears to have been paralleled in virtually every other country in the world where mining is an important sector of the economy) that I address myself tonight to the theme of this symposium. My paper is entitled ""Risk Management Strategy in Mining"" and it is sub titled ""Can Benguet Corporation Survive to Celebrate its Centennial in 2003?"". I have inserted the word ""Strategy"" and added the subtitle, because I wish to make it clear first, that my presentation to you tonight will be focused exclusively on the strategic aspect s of risk management, and second that I will limit myself to Benguet's own ""in-house"" experience and perspectives on this subject. I would caution you therefore, to consider my views within this restricted framework, and in light of the particular and sometimes peculiar circumstances within which Benguet Corporation operates."

Jan 1, 1983

By D. C. Martin, P. M. Hawley, C. P. Acott

"In bedded deposits such as coal or sedimentary iron, economic limits of mineable reserves are clearly defined by the footwall of the seams or ore-bearing units. Where open pits are developed in dipping strata, a long, high footwall slope may result. In many cases, unbenched slopes excavated along the base of the lowest mineable seam are operationally simple, economically desirable and geotechnicalty practical, although a variety of failure mechanisms may develop. This paper examines the engineering geology and rock mechanics parameters of importance in the design of footwall slopes. Possible failure mechanisms and stability analysis methods are described. Design considerations for benched and unbenched slopes are discussed with prime consideration given to development of long high stopes without benches or with a minimum number of benches. IntroductionIn bedded deposits, the ultimate depth and economic viability of an open pit in dipping strata may be controlled by the design of the footwall slope. The stability and, hence, design of footwall slopes is strongly influenced by the engineering geology and rock mechanics parameters of the slope forming materials. A clear understanding of the structural geology, engineering geology and tectonic history of the deposit is essential to assess the behaviour of the slope. This is particularly important for long high, unbenched footwall slopes such as shown in Photo I.A rational footwall slope design requires identification and assessment of all possible slope failure mechanisms with respect to the proposed slope geometry. Stability analyses of each potential failure mechanism are used to identify the main controls on slope stability and to develop appropriate slope design criteria. The optimum slope design is based on the most economic and geotechnically practical slope geometry with due consideration of operational constraints and of the possible advantages of specific remedial measures."

Jan 1, 1986

By G. Morin, F. Chiesa, B. Tougas, B. Duchesne, Jocelyn Baril, N. Giguère

"An aluminum A356 compressor impeller was sand cast using the Low Pressure technique. The casting was limited in size (170 mm in diameter, 1.2 kg in weight) and very intricate in shape thus making 3D mold printing particularly favorable; indeed, producing this part by the traditional pattern-core box route would involve mounting 12 cores inside the mold while stringent dimensional tolerances are required as the impeller blades are only 2 mm thick. Consequently the molds were produce on the X-One MFlex printer of Quebec Metallurgy Center - CMQ. A dozen castings were produced with different casting temperatures and filling times so that it was possible to assess under which conditions complete filling of the mold cavity would be achieved. Filling and solidification modeling allowed predicting misruns and metallurgical properties inside the A356 (AlSi7Mg04) casting.INTRODUCTION Recent advancements in additive manufacturing enable foundries to produce molds without the tooling (pattern and core boxes) necessary when conventional technology is used (Eyad, 2016). This is particularly advantageous when dealing with intricate shapes and/or when a limited number of parts must be produced within a few days rather than in 5 weeks. An additional advantage is gained when producing prototypes (Johnson, 2016) as changes are much less costly and time consuming when made on a numerical 3D drawing rather than on patterns and core boxes. 3D printing is normally economical for a small number of parts; however, if the part is not too big and very intricate in shape such as the part that will be studied in the present work, 3D printing can be economical even for an important number of castings to be produced. On the other hand, low pressure casting is a high integrity casting process in which the mold cavity is filled from the bottom via a transfer tube in which the liquid aluminum rises under the pressure applied at the surface of the melt as illustrated in Figure 1. The filling can thus be precisely controlled, eliminating the turbulence created when the mold is filled from the top (gravity casting). Also, the pressure applied on the melt during solidification results in excellent feeding of the casting when conditions of directional solidification are met. In the present work, the compressor impeller shown in Figure 2 will be sand cast by low pressure."

Jan 1, 2018

By S. Dallaire

"RÉSUMÉLes revêtements céramiques ont une moins grande visibilité que les revêtements métallurgiques. Ils ont cependant jour un role significatif dans noire développement technologique. Les procédés de revêtement ont permis de s'affranchir de barrières technologiques importantes dans le domaine de l'optique, de l'électronique, de l'usure, des hautes temperatures. L'introduction de nouvelles technologies ou la mise en service de nouveaux matériaux peut nécessiter l'adaptation de certain procédés actuels ou le recours a des procédés qui ont peu percé jusqu’ à maintenant.ABSTRACTApplications concerned with ceramic coatings are not as well known as those with metallic coatings. However, ceramic coatings have played a tremendous role in the development of technology. Ceramic coating processes made it possible to overcome technological barriers in the areas of optics, electronics, wear resistance and high temperature applications. Ceramic coatings can provide new properties to materials never considered for demanding applications. They can also open new frontiers and revitalize materials which are maturing or in decline."

Jan 1, 1990

By Robin Sheremeta

What is the goal of every organization when it comes to safety? Everyone Going Home Safe and Happy Every Day Good old days: Era of Death (accidents will happen) Era of Engineering: (Eg. hand rails, limitswitches, machine guards, etc.) Era of Legislation: procedures, laws and regulations (Eg. SWP?s, Mines Act) Era of Behaviour-Based Safety: (eg. STOP program)

May 1, 2010

By D. A. Whitley, R. P. Carone

"Shaft sinking by blind shaft drilling offers the mining industry a different approach to shaft construction. Benefits of blind drilling include less construction time and fewer safety problems while being economically competitive with conventional sinking methods under certain conditions in soft water-bearing formations.Technology and equipment are available today to drill blind shafts up to 20 feet in diameter and over 3,000 feet deep. This is an extension of proven techniques developed by private industry. To drill a 20-foot-diameter hole requires a specially manufactured hydraulic drill unit with a rated hoist of 2 million pounds and 500,000 ft/lb of torque.This brief paper will discuss the following aspects of blind shaft drilling:• benefits;• equipment f or drilling;• circulation methods;• circulation rates;• shaft alignment; and• progress rates to be expected.IntroductionShaft sinking by blind shaft drilling offers the mining industry an improved alternative method for shaft construction. The drilling of 20-foot -diameter shafts to depth s in excess of 3,000 feet can be done by utilizing equipment specifically designed and manufactured for this purpose. This equipment is a distant cousin, at best, to standard oil well drilling rigs. The actual configuration of these drilling machines will be discussed in a following section.To most people, the drilling of mine shafts may seem to be a new or at least recent technology. However, as early as the I920s, German and Dutch miners were drilling 24-foot diameter shafts for coal mines. What led ""miners to resort to drilling were ground conditions that still plague conventional shaft sinkers today: soft , water-bearing formations. The major drawback to these early attempts was a low penetration rate due to poor bit cleaning. This, however, was not the end of early shaft drilling activity. From 1936 to 1950, a number of mine shafts were drilled by the calyx or coring method. This method employs a bit with a large bore down the center. As it drills, it cuts a core. When 5 to 10 feet have been drilled, the core is removed. The disadvantages of this method were the time and work involved in breaking the core free, and it was inadequate in soft water-bearing ground."

Jan 1, 1981

By X. Wu

Tunnel Boring Machines (TBMs) are widely used for tunneling in urban areas because of their high advance rate, precise as-built profile and minimal impact to buildings and traffic on the ground. For a tunnel built by a TBM, there are strict requirements on alignment control and safety. To meet these requirements, it is important to monitor the position of the TBM. In the current practice, the TBM position data, including advance distance and line and level deviations, are reported manually to the managers on a daily basis. To interpret and analyze the position data, the managers also need to refer to various construction drawings. This practice is untimely, inefficient, and error prone for decision making. To improve the current practice, an automatic approach for real-time as-built tunnel product modeling and visualization is proposed, based on TBM position and orientation data autonomously sourced from the Virtual Laser Target Board (VLTB) TBM Guidance System developed at University of Alberta. Related information of the tunnel project, such as the as-designed alignment, soil layers, the ground, existing utility lines, is also visualized together with the model of the as-built tunnel. The modeling algorithm is presented step by step. Its application in a real-life drainage tunnel project is discussed and limitations are also identified.

Aug 1, 2013