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By Zhen Lei

In Alberta, Canada, heavy industrial projects are constructed using a prefabrication approach: spools and pipes are produced in the factory, and are assembled into modules that are transported to the industrial plants for installation by mobile cranes. Planning the onsite mobile crane operations is critical to the project budget and schedule. However, due to the large magnitude of industrial projects, manual heavy lift planning is tedious, and the results are not particularly responsive to site changes. This paper introduces an integrated mobile crane management system developed by PCL Industrial Management Inc., in collaboration with the University of Alberta, which investigates crane location selection and path checking for field module assembly. The project information is stored in a database, and the proposed system retrieves data, performs the calculations, and records the results back to the database; the calculations involve automatically selecting locations for the mobile crane, considering the crane capacity, lifting range and utilization. Lift paths for modules are checked for feasibility based on selected locations, satisfying the site and crane configuration constraints, and crane walking paths are planned if needed. The designed system is tested in an industrial project to validate the effectiveness of the system.

Aug 1, 2013

By F. J. Alcock

IN the summer of 1934, gold was discovered on Lodge bay, on the north shore of lake Athabaska in northern Saskatchewan, about fifty miles east of the Alberta boundary line. The first claims were taken up by the Consolidated Mining and Smelting Company of Canada, Limited, and there was a 'rush' to locate similar showings. Staking continued through the summer and succeeding winter, and in the spring of 1935 the provincial government established a recording office at a convenient point which is central to the more important holdings and where 'planes can land in any weather. During the past summer, the name of this townsite was changed from Beaverlodge to Goldfields, and a post office was established here. The season was one of great activity; a great deal of assessment and development work was carried out and a large amount of further prospecting done. In addition to the work by private companies, geological investigation was carried out in the region by a Federal Geological Survey party under the charge of the writer and a reconnaissance examination was made of an area of some 7,000 square miles surrounding the region of particular interest. Though this was the first discovery of gold in the region it was not the first occasion that prospecting had been carried out along the north side of lake Athabaska. Over twenty years ago, a number of prospectors were at work in the area and a large number of claims were staked, many of which were never recorded. One man by the name of Piché, in the years 1910, 1912, and 1913, took up a considerable number of claims north of Pine Channel narrows, east of Fond du Lac. His discoveries, which consisted of small showings of sulphides in sedimentary gneiss, proved to be of no economic importance. In 1915, a sudden widespread interest was aroused by the report that a sample of ore collected near Fond du Lac had yielded a very high assay in silver. In March and April of that year, prospectors began to rush into the field by dog teams to take up claims, and, as soon as the Athabaska river was free of ice, others started by boat from Athabaska Landing. Some hundreds of claims were staked and recorded in the Dominion Land Office at Edmonton or at Fort Smith. By July, most of the prospectors had? left the region, having failed to find any silver ore. In 1921, considerable prominence was given to the area a few miles east of Goldfields by reports that very large masses of iron ore were available there. Claims were taken up, but the material is much too low grade to be considered commercial ore.

Jan 1, 1936

By H. J. Burchell

"IntroductionTHE PURPOSE of this paper is to introduce the reader to rock bolting and its present application in mining.Rock bolting consists of bolting insecure rock to secure rock in order to form a safe structure. The insecure rock may be a weak beam or loose from arching or from sloughing. The material is strengthened and held in place before damage can result.Little is known of the limitations of rock bolting; to date, work has been carried on by trial-and-error, with large safety factors being used. Rock bolts have been principally used for roof support. Bolting offers a new field of support to the mining industry: it now has a permanent position as a ground control method.HistoryRock bolting is a relatively new means of support, its exact origin being unknown.Bolting has been in use at the St. Joseph Lead Company's property in Southeastern Missouri for the past twenty-six years, the first attempts having been hit-or-miss trials before a systematic attack was made. Many instances of occasional use of rock bolts have come to light .in widely separated mining camps, .some dating back forty years.The first installations were made as supplements to wooden timbering where space was restricted. The excessive costs compared to wooden timbering hindered their advancement for a number of years"

Jan 1, 1955

By J. M. Livingstone

"This paper covers some of the problems confronted by Canada's railways in moving bulk materials from their source to the dock-site. The ""cost center"" concept is presented, and hypothetical examples of its use given. Also discussed are systems design, the unit train and pipelines.INTRODUCTIONCANADA LIVES BY RER EXPORTS and the Port of Vancouver by the exports of the Mountain and Prairie Empire at her back. The most recent estimates of off-shore shipments of bulk from the Port of Vancouver rise to 35.8 million shipping tons in 1985 and deep-sea general cargo estimates, in and out, are estimated at 7.6 million shipping tons for the same year. This compares to 7.67 and 2.87 million shipping tons, respectively, in 1965."

Jan 1, 1968

By John C. Taylor

"The non-ferrous pyrometallurgical industry has been under extreme pressure since 1980 and significant changes are taking place, principally in the copper, nickel and lead industries. This paper reviews some of these changes, particularly with respect to smelter capacity, major technical trends, and the industry's response to increased energy costs and environmental constraints.The Canadian metal mineral production for 1985 has been estimated at a value of over $8 billion, of which half is derived from copper, nickel, lead and zinc production. It is in our national interest that the Canadian industry remain competitive in the world market and continue its traditional contribution to the Canadian economy. IntroductionPyrometallurgy by definition requires energy, usually in the form of fuel, and produces process gas streams which can no longer be discharged directly to atmosphere in most countries. While the industry has been under varying degrees of pressure over the past fifteen years, it is just since the early 1980s that major changes have taken place, due, to a large extent, to an oversupply on the primary metal markets and depressed prices. These factors, combined with a surge in the price of oil, have resulted in some trends developing which must be recognized by those in the industry who plan to be in operation and competitive in the next decade.Although the value of Canada's mineral production, in terms of constant dollars, has decreased by more than 35% over the period from 1980 to 1985, the bulk of this production is exported and the industry still makes a significant contribution to the Canadian economy."

Jan 1, 1988

By Stephen C. Tadolini

"The use of a torque wrench to establish the amount of actual load developed on an expansion anchor bofting system dates back to work completed in the early 1950s. The advent of ultrasonic measurement systems and hydraulic torque wrenches has made it possible for the U.S. Bureau of Mines to perform torque-tension measurements in the laboratory and the field much more accurately. The results indicate that the amount of initial boft preload may be overestimated by amounts in excess of 45% of the expected load using torque wrenches. This inaccuracy is primarily due to the friction that occurs between the bearing plate and the head of the boft. These parameters become extremely important when the support system is being used to prevent joint members from slipping relative to each other or when the boft acts as a heavy spring to clamp two or more sections together. Methods to overcome the frictional losses are presented in conjunction with a laboratory method to determine the actual torque-tension ratios for expansion anchor and combination bolting systems.IntroductionMechanically anchored roof bolts have been widely used in the mining industry since their introduction in 1947. Estimates made in 1989 indicate that out of 85 million fixtures, approximately 49 million bolting fixtures still use applied tension to complete the reinforcement necessary to maintain stable openings. Nearly 85 million bolts are used yearly. The most widely used bolt is the resin-anchored headed rebar, followed by standard mechanical roof bolts, specialty bolts (mechanically anchored, resin enhanced fixtures) , and combination bolts . Po st-tensioned resin rebars, combination systems, and friction stabilizers make up the remaining 10% of the units used (Fig. I).For mechanical, combination, and tension rebar bolts, the bolt tension is the primary means of reinforcing the roof, but in many cases, because of poor installation procedures, the bolts are ineffective. Mine operators recognize the importance of proper installation procedures. Long-term bolt tension measurements are required in the Code of Federal Regulations (CFR)In each bolting cycle, the actual torque or tension of the first tensioned bolt installed with each drill head shall be measured immediately after it is installed. Thereafter, for each drill head used, at least one roof bolt out of every four installed shall be measured for actual torque or tension. If the actual torque or tension of any roof bolts measured is not within the range specified in the roof control plan, corrective action shall be taken."

Jan 1, 1991

By E. M. De Souza, R. Penner

"Water is encountered at the majority of underground mines, both over their lifetime and during each stage of development and production. The dewatering system is one of the most important and costly components of an underground mining operation and it is often not well designed and analyzed. An effective design of a mine dewatering system will greatly reduce its energy cost as well as improve working conditions and reduce production costs. A computer-based system, called Qpump, has been developed to assist the underground operator to effectively design and/or assess over-all and local mine dewatering systems. The design features and principles used in the development of Qpump are introduced and an example which illustrates typical applications is presented.IntroductionTraditionally, dewatering operations have been given lower priority than many other operations in underground mining. Invariably water will be encountered during the sinking of the mine shaft, during development and subsequent production. The dewatering system thus becomes a very important component of an underground mine operation and, in fact, any mine manager will attest to the importance and necessity of an efficient mine dewatering system.The water problem is of varying importance at different mines. There are several factors that contribute to the water encountered. It is a function of the mining method and techniques utilized (backfill system, drilling and raising technology, dust control sprays, shaft water rings, etc.) and of prevailing conditions (ground water, rock structure and permeability). In some cases a mine may be so dry that little pumping is required while in others, the weight of water pumped may exceed by many times that of ore mined.The successful design and application of a mine dewatering system is dependent upon the operating conditions of each specific operation. There are no standard procedures and systems which can be used for all mining situations. However, an effective water system will greatly reduce the energy and production costs of a mine, improve working conditions and eliminate headaches because of flooded working places."

Jan 1, 1993

By Matt Manson

?? Current Exploration and Assessment ?? Overview of Potential Development ?? Infrastructure ?? Opportunities and Challenges ?? Renard? 1-10 kimberlite pipes and ?Lynx-Hibou? kimberlite dyke system within ?Foxtrot? property ?? 50/50 Joint Venture between Ashton (a subsidiary of Stornoway) and SOQUEM ?? Discovered 2001-2003 ?? Québec is routinely assessed as one of the top mining jurisdictions in the world ?? Agnico-Eagle Mines Ltd. Is Stornoway?s largest shareholder and a leading mine developer in Québec

May 1, 2008

By Ali M. Ghazi, Ronald J. Goble, Lowell S. Whiteside

"Geerite (Cu1.6S) is a rhombohedral copper sulphide which occurs naturally in epitactic replacement of sphalerite; cell dimensions closely approximate those of the host sphalerite.Geerite-type structures can be produced by leaching digenite (Cu1.8S) in ferric sulphate solutions. X -ray diffract ion and electron microprobe studies indicate that eight metastable geeritetype structures can be produced, depending upon the concentration of f erric sulphate solution used and the duration of the each. Although compositions cluster on or near values observed for natural phases, optical properties indicate that we are dealing with polymorphs of these phases. Leaching of chalcocite (CU2Sj in dilute f erric sulphate solutions produces similar results. In contrast, leaching of chalcocite in more concentrated solutions seems to produce true analogues of natural minerals.During froth flotation, sphalerite is activated with a monolayer of floatable copper sulphide with the composition, CuS, of the mineral covellite. However, covellite is not significantly more floatable than sphalerite, and has an incompatible structure because of the presence of covalently-bonded atoms of sulphur. Leaching ofdigenite was used to produce a polymorph of covellite with a geerite-type structure, compatible with that of sphalerite. This polymorph has a flotational behaviour similar to copper-activated sphalerite, suggesting that the monolayer has a geerite-type CuS structure. IntroductionIn an ideal close-packed sulphide structure the distance between sulphur layers, D, is equal to 2R 2/3, where R is the radius of the sulphur atoms. In sulphides with covalently-bonded sulphur layers, such as covellite (Fig. I), D will be an average of the number of covalentl y-bonded and close-packed sulphur layers, weighted as to the relative number of each type of layer. Both D and R are spacings which are readily identifiable structurally and on X-ray diffraction patterns. Goblel has shown that for copper-iron sulphides with metal-to-sulphur ratios between 0 and 2 and copper-to-total metal ratio s between 113 and I there are strong correlations between composition and measured D and R distances (Fig. 2). D can be represented by a single empirical equation relating interlayer spacing to composition; R must be represented by three equations relating the radius of sulphur atoms to composition. One of these equations (R, in Fig. 2) represents ideal close-packed behaviour, the other two represent sulphur radii greater than (R1) or less than (Rh) the ideal."

Jan 1, 1988

By Arsalan Talebzadeh

Construction -Surface ?First two intake fans constructed in 2007; third fan added in 2008 to reduce resistance in the system. 450 HP fans. ?Excavation for exhaust fans started in 2008. ?In parallel with underground construction in preparation for the changeover. ?Bulkhead in place prior to completion/ commissioning of

Oct 1, 2010

By G. D. Garland

The influence of natural electric currents, induced in the earth by changes in the earth's magnetic field, on the electric logging of boreholes has not always been recognized. Measurements made with fixed electrodes of changes in the vertical potential gradient in a hole near Calmar, Alberta, have indicated the effect of earth currents related to magnetic disturbances. It is found that appreciable errors in self-potential logging could arise during periods of magnetic storms, but the precise pat-tern of disturbance in any area seems to depend on the local structural conditions. As the amplitude of the natural earth currents increases toward the auroral zone, it is suggested that periods of magnetic disturbance be avoided, if possible, when electric logs are taken in the northern part of the western sedimentary basin. NATURAL electrical currents flow continuously near the surface of the earth, apparently as a result of electromagnetic induction

Jan 1, 1962

By Hiwa Salimi, Foley. Stephen R, Loghman Moradi

Common water-miscible organic solvents including DMSO, DMF, methanol, ethanol, acetone and THF in combination with HCl and low concentrations of H2O2 were investigated for dissolution of gold. THF showed the best result demonstrating that gold powder could be completely dissolved in 1.5 hours in 1.0 mol/L HCl and 0.2 mol/L H2O2. No complete gold dissolution was observed for the rest of solvents even after 24 hours. The rate of gold dissolution was measured by dissolving gold wire in THF/HCl/H2O2 mixture. The rate of gold dissolution in optimised condition was 75 g m-2 h-1 at room temperature and significantly increased to 590 g m-2 h-1 by raising the temperature up to 60 oC. Although a THF/HCl/H2O2 mixture showed a slower dissolution rate in comparison with aqua regia, however the applied conditions are considerably milder which is highly promising for gold leaching in an industrial scale.

Jan 1, 2015

By Colin E. Dunn

The high mobility of gold within the plant kingdom results in detectable accumulations of gold in many plants. Concentrations vary within individuals, among species, and with seasons. From an evaluation of the chemistry of easily acce sible organs of common pecies in the northern forests, it is concluded that alder twigs (or leaves) and conifer bark scales are the vegetation components of greatest use in the earch for concealed gold mineralization. Maximum anomaly enhancement is obtained from twigs collected in the spring. Examples are given of urvey conducted in the La Ronge Domain using 1) jack pine bark (A nglo-Rouyn and Upise Lake areas) ; 2) alder twig (McLennan Lake) ; 3) black spruce bark (Rod Zone near Mallard Lake, and at Waddy Lake) ; and 4) multi-media (Tower Lake). At the latter two sites gold-bearing till is blanketed with late glacial material. Gold enrichment in the plants suggest that the roots are ab orbing gold from the underlying till. Complex processe control the uptake and retention of gold in plants. An understanding of these processes pem1its biogeochemistry to assist in locating near- urface mineralization .

Jan 1, 1986

By S. Nafisi

Permanent mould casting may be regarded as a near net shape manufacturing process where simple to very complex shaped engineering components are fabricated with high degree of precision in a metallic mould, In this group, High Pressure Die Casting (HPDC), have attracted more attention because of its production rate, where both liquid and semisolid metals (SSM) can be cast with high degree of precision and versatility. The SEED process, Swirled Enthalpy Equilibration Device, the new process for semi solid metals slurry production route, consists of two steps: The initial step involves extracting specified amount of heat from the molten metal to generate liquid-solid slurry, i.e, mushy structure, followed by drainage of remaining liquid to produce a compact free standing feedstock for rheocasting operation. In this paper, microstructural evolution during the process and some initial casting results of automotive components an also reported.

Jan 1, 2005

By John Loui Porathur

Highwall Mining has been recently introduced in India. The first Continuous Highwall Mining extraction in India started operating at Ramagundem Opencast Project-II (OC-II) of Singareni Collieries Company Ltd. (SCCL) in December 2010. A new hybrid empirical and numerical modelling approach has been devised to design web pillars for the initial Highwall Mining sites in India, considering the complex geology, such as existence of thick seams and multiple seams in close proximity. This paper gives the scientific elucidation of a comprehensive design methodology adopted for the above mentioned Indian Highwall Mining sites. The design technology includes web pillar design for multiple seams using hybrid empirical and numerical methods, slope stability assessment, ground movement monitoring, and recommendations for conducting blasting operations in the vicinity of Highwall Mining extractions.

Aug 1, 2013

By David Eichenberg

A154S A154N After 3 Years of Mining ?Current mining Level A154S 280RL ?110 Vertical metres of A154S ?Current mining Level A154N 300RL ?100 Vertical metres of A154N ?Variations in Kimberlite Volume ?Ore Types and Plant Production

May 1, 2006

By D. A. Beck

The load-deformation response of discontinuous rock under static and dynamic loading conditions has been simulated using Explicit Finite Element models. The intent of the analysis was to investigate the effects of specimen size and confining stress on strength, dilation and comminution. The simulations allow the development of homogenised constitutive material properties for discontinuous rock masses using laboratory scale measurements and representative Discrete Fracture Networks (DFNs). A procedure for this is presented which includes a comparison of measured seismic response in a mine to the Dissipated Plastic Energy (DPE) that is released in the simulated rock masses. The models also show how confinement and scale affect the stress-strain and DPE response of the simulated rock specimens, reproducing a number of known rock phenomena that are often poorly captured in geotechnical modelling. A case study is presented showing a satisfactory match between the model-derived, homogenised material properties and values achieved by calibration of a mine-scale model where many thousands of seismic, displacement and damage measurements were available.

May 1, 2009

By M. T. Shehata, R. W. Revie, M. Elboujdaini

Environmentally assisted cracks in linepipe steels are initiated either as a result of stresses in combination with environmental effects, as in stress corrosion cracking (SCC), or as a result of trapped hydrogen in the steel, as in hydrogen-induced cracking (HIC). To understand better the mechanism of the crack initiation process, key metallurgical and environmental elements that can affect the cracking phenomena were investigated and are reviewed in this paper. The complexity of both cracking phenomena results from the dependence of SCC and HIC on multiple metallurgical, mechanical, and environmental parameters that may all influence both crack initiation and propagation; e.g., composition, microstructure and non-metallic inclusions in the steel, applied stress, water chemistry in the field, and ionic concentrations in the groundwater near the pipe surface to name a few for SCC. In addition, for HIC phenomena, one can add the concentration of H2S in the fluids transported in the pipe as well as concentration of CO2, pH, etc. In this paper, cracking of linepipe steels is analyzed critically, with particular attention to the crack initiation process. The paper is divided into two parts: The first part covers SCC and the second covers HIC.

Jan 1, 2005

By C. R. Kato, G. Proulx

"Within the continuous scenario of reduced aluminium price and plants production costs increase, the energy consumption optimization in the aluminum electrolytic pots continues as the main focus for the producers. Energy consumption was chosen as a key performance indicator to drive the efforts and actions for improvements. Alcoa improved the energy consumption by approximately 3% from 2005 to 2015. This improvement was a result of best practices implementation, new technologies introduction, strategic actions with plant curtailments and management practices. The main objective of this paper is to highlight the importance of the management practices for planning and operational improvements beyond the technology changes. About 10 years ago, Alcoa reorganized its approach to retain knowledge in the Smelters by using a Best Practices format. For each specific subject, a skilled team defined the minimum requirements and the Best Practices for several aspects of operation and maintenance, which affect the environment, safety, cost, customers and performance. These Best Practices were deployed to all Smelters combined with training sessions to process and operation professionals. We will describe how the Best Practices were organized, the deployment strategy used, and the approach to measure the plants’ success. We will describe the management approach that includes Manufacturing Analyses focused on 3-year potential, annual planning, and weekly monitoring of plant stability. A manufacturing analysis is organized at select plants with cross-functional participation of specialists from technical, operational, procurement and finance. The output of a manufacturing analysis includes a roadmap of enablers to improve energy efficiency. A quarterly follow-up of enabler deployment is held with the plant and resources that participated in the analysis. Annually, there is a Planning Process where energy consumption enablers are selected to be implemented during the next 3 years for each plant. A monthly critical analysis is made by the plants with regional best practice support. On a weekly basis, key performance indicators are reviewed with determination of a stability index for each plant. Any deviation signal of unstable condition is alerted and supporting resources are diverted to the plant to reverse trend with countermeasures.INTRODUCTIONDue to factors like excess aluminum in the market and lower consumption in China, the LME price is declining along the last years, as showed in Figure 1. In 2011, the price peaked at US$ 2,400/ton and since then, continues to trend down and approaching the lowest level at US$ 1,500/ton in the last 5 years."

Jan 1, 2016

By Michael Magerstädt

Material loss by abrasion of contact surfaces of pipes, chutes, pumps, and other equipment in contact with ore is one of the main reasons for downtime of mining operations. Abrasion protection materials in use range from expensive tungsten carbide overlay to hardened steels, ceramics, as well as polymers, particularly polyurethanes (PUR). This paper describes abrasion protection products made from High Performance Polyurethane Elastomers. An interior pipe coating was developed that exhibited outstanding abrasion resistance and an extremely high adhesion to steel. Years of field testing in oil sands tailings as well as applications in slurry lines (e.g., phosphate slurries) have proven the performance of this material. A proprietary field joining process was developed and successfully applied in the field. This joining process requires only one field weld per joint very similar to the joining of uncoated pipe. No internal re-coating is necessary adding savings during pipe laying to the significant savings of reduced down time. Using the building-kit chemistry of polyurethane synthesis, similar high performance elastomers were used to extend the life time of ball mills. An intelligent system was developed in which wear parts contain sensors reporting the actual wear thereby optimizing maintenance interval leading to significant cost savings for the operator. Test data as well as field experience with High Performance PUR Elastomers for abrasion protection in mining are presented.

Aug 1, 2013