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By K. J. Brouwer, J. P. Haile

"Construction of the first stage of the tailings disposal facility for the Montana Tunnels Project was completed in October 1986. The project is located 37 km south of Helena, Montana, and involves mining of42 million tons of weathered diatreme are at a rate or 13 500 tpd to produce a gold/silver dore, as well as lead and zinc concentrates. The tailings disposal facility for the project includes a fully drained tailings impoundment for storage of the tailings solids, and a process waterpond for storage of all decanted water prior to recyling to the mill. The over-all facility is designed to achieve the basic objectives ofminimizing seepage to the environment in the short- and longterm, and achieving a fully drained stable tailings mass suitable for immediate reclamation on completion of mining. Specific features of the design include a soil bentonite seal and drainage system within the tailings basin, a free draining embankment with a design flow-through capacity of 4000 US gpm and an ultimate height of 230 ft (70 m), and a soil bentonite lined make-up water pond with a capacity of 420 acre-feet (530 000 m'). The tailings will be discharged in a rotational sequence through multiple spigot offtakes to achieve a thin-layer low energy laminar flow. This 'sub-aerial' deposition results in higher stored densities and maximizes liquid-solid separation on the tailings beaches. The over-all design played a major role in the successful permitting of the project, and was significantly cheaper than a conventional wet disposal system, with overall unit costs for tailings disposal of less than US$0.36 per ton.This paper outlines the site characteristics and the tailings material properties and their influence on the design. Extensive use was made of naturally occurring free draining materials as well as bentonite modified soil liners within the tailings basin, embankment and retention ponds. General construction procedures for the various components are described, as well as on-going construction requirements utilizing materials from the open pit. Finally, the over-all costs and unit costs for tailings disposal are presented."

Jan 1, 1988

By Etienne Roy Grégoire

Since the early 1990s, the Canadian mining industry has been increasingly defined by the signing of Impact and Benefit Agreements (IBAs) between mining companies and Aboriginal peoples. While these agreements are intended to complement the legal system, they also serve to establish the legitimacy of mining projects and to encourage the harmonious integration of these projects into their social and environmental contexts. Beyond their practical implications, what are the effects of such agreements on the ability of Aboriginal communities to access the institutional space where the authorization of mining projects and the conditions of their implementation are decided? Can we view IBAs as a preliminary step towards the operationalization of the principle of Free, Prior and Informed Consent? This paper aims to explore the potential of IBAs as a sustainable solution to the legitimacy issues that result from the implementation of the formal regulatory framework governing mining activities in this jurisdiction. We highlight what constraints and opportunities the James Bay and Northern Quebec Agreement (JBNQA) engenders for local communities and draw attention to the ways in which the negotiation of the Raglan IBA and the environmental evaluation processes act upon each other. We find that certain structural problems - and problems of legitimacy ? related to mining in Northern Quebec cannot be solved by the sole signature of an IBA, which suggests the need for caution when considering such agreements as a panacea. The Raglan case demonstrates that IBAs, like other modes of regulation relying on the direct interface between companies and communities, would benefit from a stricter framework and more explicit ties with official regulation channels.

Aug 1, 2013

By D. Seo, P. Au, S. Yandt, N. Tsuno, A. Sato

Nickel-base single-crystal superalloys are used for gas turbine airfoil applications due to their excellent high temperature properties. A good understanding of the mechanical response of these alloys under different temperature and loading conditions is essential for modeling their behavior. In this study, the low cycle fatigue behavior of CMSX 2 oriented with the loading axis along [001] was investigated under zero-compression strain-controlled loading at 1100°C. The experiments were performed with or without a two-minute dwell (hold) in compression. The microstructure before and after testing was analyzed to understand the deformation characteristics including the effect of dwell.

Jan 1, 2010

By Kosei Ishida

To achieve renovation work without noise, the authors developed techniques of manufacturing pre-cut interior finishing components for renovation work. In this paper, to achieve the system of pre-cut interior finishing components, the authors describe a measuring method of reinforced-concrete structure by 3D laser scanner and then describe a method of making a design of pre-cut interior finishing components with the polygon model. Using these two methods, the steps of manufacturing pre-cut interior finishing components consist of the following four steps: First, measure the building shape using a 3D laser scanner. Secondly, integrate a point cloud data and retrieve the markings on the floor. Then, create a polygon model of the building based on the point cloud data. Lastly, make a drywall design using a polygon model. To evaluate the technique feasibility of manufacturing pre-cut interior finishing components, the authors have conducted an experiment of the finishing interior work of the drywall. Using pre-cut interior finishing components, the authors have been able to achieve interior finishing work without noise.

Aug 1, 2013

By J. A. Allan

"The history of the development and application of controlled recirculation systems in U.K. collieries is traced and the theory behind such systems briefly examined. Specific applications for dealing with dust and dust/heat problems in headings, for which practical experience is currently available, are described. Consideration is given to the special features which these systems introduce in the underground situation and to the essential safeguards which are required for their safe use.IntroductionRecirculation of air is a commonly used technique in genera l ventilation and air conditioning practice, but has always been regarded with some suspicion for mining applications. This is perfectly understandable in view o f the hazardous conditions which can occur with dangerous forms of recirculation in mines. However, certain controlled recirculation techniques can offer advantages, particularly in the field s of dust and climate control in headings, provided that they are designed, Installed an d managed with full comprehension o f all aspects of the system and always bearing in mind that from the point of view of serious firedamp ignition risk, headings are potentially the most hazardous places in coal mines.BackgroundProbably the first recorded use of deliberate recirculation in British collieries was reported by Lawton in 1933. This researcher described trials, undertaken under the auspices of a national committee on ""The Control of Atmospheric Conditions in Hot and Deep Mines"", involving attempts to increase the velocity, and thereby the cooling power on hot faces, by means of simple recirculation systems using fans and ducts delivering recirculated air in the opposite direction to the normal face airflow. No significant cooling advantage was obtained and there is no subsequent record of this work being continued. During the discussion on this paper, there was considerable disbelief that fire damp percentages had not increased significantly when air was recirculated, but apparently no attempt was made to establish why this should be. It is of interest to note that J. Ivon Graham, one of the contributors, recommended that recirculation should be tried in stone headings for the control o f dust, as he believed that ""there may be scope for recirculation and filtration of the air under certain circumstances in such headings"". This idea was not developed for another forty years."

Jan 1, 1983

By G. Kollberg

"IntroductionThe SALA Caravan Mill system represents a proven concept for the design and operation of mobile and semi-mobile ore dressing plants.The Caravan Mill has been developed to meet the demand for a flexible processing plant to be used for small and medium-sized orebodies or for pilot investigations of deposits directly at the mine site e •The first Caravan Mill installation was put into operation in 1970 and a number of plants have been delivered world-wide since then.The Caravan Mill system has great flexibility both in capacity, ranging from 50 to 1000 tons per day, and in process combinations. The process modules available are:• crushing by jaw and cone crushers;• pre-concentration by the Dyna Whirl Pool dense media system;• grinding by wet rod or ball mills;• separation by gravity, magnetic, flotation or leaching-CVP adsorption methods;• dewatering by lamella or conventional thickeners and vacuum filters.To form complete plants, auxiliary equipment is also available, such as:• bins, feeders and conveying systems;• power generator units;• water tank and pump for process water;• interconnecting piping and cables;• erection and service tool kits;• set of spare and wear parts.For mine sites with rainy or winter conditions, a plastic tent with air heater can be supplied to cover the ore dressing equipment. Each module is workshop assembled complete with slurry pumps, internal pipe work, electric wiring with plug-in connections, hoses, etc., all arranged for quick and simple connection between the units. Before delivery, each unit is tested in the workshop."

Jan 1, 1982

By R. J. Smyth

A Steel Compression Reinforcement Repair Technique (PetroSleevel) system has been developed that has the ability to repair pipeline defects such as stress corrosion cracking (SCC) without requiring welding to the operating pipeline. The Technology has been used to repair active cracking in ERW seam and cracking in the pipe body. All repairs were performed while the pipeline was in operation. This paper will discuss the engineering theory, testing performed to verify the engineering theory, and examples of actual sleeve installations.

Jan 1, 2005

By X. Cao, B. S. Naik, D. L. Chen, P. Wanjara

AZ31B-H24 Mg alloy sheets with a thickness of 2 mm were friction stir lap welded (FSLWed) at two tool rotational rates of 1000 and 1500 rpm and two welding speeds of 10 and 20 mm/s. The tensile behavior of the FSLWed AZ31B-H24 Mg alloy was then evaluated at low (-40°C), room (25°C), and high (180°C) temperatures. It was observed that the failure load increased with decreasing tool rotational rate and increasing welding speed. The maximum failure load occurred at a tool rotational speed of 1000 rpm and a welding speed of 20 mm/s at all temperatures tested. It was also noticed that at the high test temperature, the samples failed along the sheet interface, i.e. shear fracture. At the low and room temperatures, the samples failed on the advancing side (AS) of the top sheet near the interface between thermo-mechanically affected zone (TMAZ) and stir zone (SZ). The different modes of fracture observed are associated with the hooking defect.

Jan 1, 2014

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 Robert W. Plummer

"This paper describes the use of Geographic Information Systems (GIS) as a tool for mineral exploration by using the Eskay Creek area of northern British Columbia as an example. Data entry, analysis and output are discussed. Examples of some of the capabilities of the technology are presented.The main benefit of the technology is being able to perform complex and sophisticated searches of large and diverse data sets to highlight exploration targets. A GIS is a powerful data management tool that can be used in mineral exploration. It is a computer based system that is designed for the collection, storage and analysis of objects and phenomena where geographic location is an important characteristic. The main function of the GIS is to produce information for the geologist from a variety of sources (geology, geophysics, geochemistry, mineral deposits and so forth) quickly and efficiently. This allows the geologist to examine large amounts of data in a fraction of the time than can be done using conventional manual methods."

Jan 1, 1992

By W. Cholewa, T. S. Golosinski, J. Wedzicha

"Power requirements of belt conveyor drives are usually estimated based on the calculated belt tension which equals the sum of unit resistances to motion which the belt has to overcome. In most situations, the value of various unit resistances can be accurately predicted using published information (5,6,8,12). A simpler approach calls for use of standard formula and tabulated values of related factors which reflect various features of both the conveyor and the transported material (2,3,7) . None of these approaches is reliable when materials with unique properties are conveyed, nor if applied to conveyors working in extreme climatic conditions. Such is the case of oil sand mines in northern Alberta.There the bitumen content of oil sand causes it to behave in a unique manner. Furthermore the conveyors operate year around, with winter temperatures often lower than - 40°C. It was the objective of presented investigations to quantify the power requirements of conveyors, and related resistance to motion for the conveyors used in oil sand mines during winter operations.The other objective was to quantify the drive power requirements of oil sand conveyors during start-up. These requirements are usually much higher than those during norm al operation, and their quantification is of paramount importance for operation of large conveyors."

Jan 1, 1992

By D. W. Euler, B. J. Clauzier

"Implementation of an effective energy management system will reduce energy costs without impacting negatively on production.The energy management system must be designed to complement the operation and be integrated with the organization. It must be reliable and easy to use but most important, it must have an accurate and timely feedback reporting system to allow the operation to take appropriate action.Falconbridge Limited was one of the first three companies to be awarded the energy monitoring demonstration program in May 1987. The program is sponsored jointly by the Ontario Ministry of Energy and Ontario Hydro.This paper describes the approach taken by Falconbridge Limited to implement the Onaping Area Energy Management System.IntroductionThe objective of the project was to implement an effective energy management system, capable of reducing energy costs without impacting negatively on production.Energy management systems must be designed to complement the operation and to be integrated with the organization. The system must be reliable and easy to use, but most importantly, it must have an accurate and timely feedback reporting system to allow the operation to take appropriate action."

Jan 1, 1990

By M. Cossette, V. H. Tran

"How can the durability of asphalt pavement be doubled without increasing highway budgets? Asphalt containing asbestos can provide the desired performance with additional costs being made up by longer life. The addition of a low percentage of asbestos to an asphalt mix permits a higher asphalt content without any consequent loss in stability. It is mainly the higher asphalt content that provides improved performance and durability, although the fibrous reinforcement plays a key role in preventing the propagation of micro-fissures. As well, several international studies show that, thanks to the latest production techniques, no environmental hazards need be incurred.RésuméComment doubler la durée des chaussées d'asphalte sans augmenter les budgets de voirie? L’asphalte contenant de l'amiante peut offrir les performances souhaitées et l'augmentation des couts initiaux peut être rapidement compensée par une durée prolongée. L’addition d'une faible teneur en amiante courte il l'enrobe de bitume permet des teneurs en bitume plus élevées sans subir une perte de stabilité en conséquence. C'est principalement la teneur accrue en bitume qui assure un améliorations propriétés physiques et une augmentation des performances mécaniques, ainsi qu'on prolongement de la durée. Cependant, le renforcement fibreux joue un rôle clef en prévenant la propagation éventuelles micro-fissures. Les nouvelles techniques évitent tous risques environnementaux"

Jan 1, 1991

By D. Mu

A method is presented for evaluating the effective gas diffusion coefficient of porous media. A series of random-distributed porous solids with different porosity are generated, a solution of the gas diffusion equations inside the porous media is obtained using the finite element method (FEM), and then the effective gas diffusivities are computed. The results show that there is a percolation threshold sp, and this percolation threshold decreases with an increase in the connectivity of the pore network; the relationship between the effective diffusivity and the porosity is strongly nonlinear when the porosity £ is less than about 0.2; and is quasi linear for higher porosities. The threshold decreases with increasing the connectivity of the pore network. A formula relating the effective diffusion coefficient with porosity is proposed.

Jan 1, 2005

By M. Walmsley, D. Maynard

"This paper describes the use of terrain and soil information in the planning of mine developments, particularly in satisfying many of the existing provincial regulatory requirements. It is also noted that, if properly used, this will provide a solid data base for cost-efficient and environmentally acceptable land use.IntroductionIn planning the development or expansion of a new or existing mine, engineering alternatives are judged on many factors, one of which is the environmental influence. Ecological investigations, ensuring consideration of a rational approach to managing land use and environmental impacts, should be carried out prior to a final decision being made on mine development. The Pit Slope Manual (CANMET, 1976) suggests that both baseline aquatic and terrestrial data be collected and interpreted in such pre-mining surveys. In British Columbia, planning procedures now exist which incorporate biophysical studies to help identify, assess and manage major environmental impacts associated with mine development.Methods outlined in the Guidelines for Coal Development (E.L.U.C., 1976) have been successfully applied in recent years. Following this example, the Inspection and Engineering Division of the B.C. Mineral Resources Branch prepared guidelines to help expedite the development of new base metal mines (Procedures for Obtaining Approval for Metal Mine Development; Ministry of Energy, Mines and PetroleumResources, 1979).The metal-mine guidelines require the proponent of a new mine development project to prepare a two-stage assessment proposal which systematically moves from a preliminary feasibility study (Stage I) to a final project design (Stage II), including application for regulatory approvals. One purpose of the Stage I report is to provide a description of the existing environmental conditions that could be affected by the proposed development. A preliminary environmental impact assessment should also be reported. The Stage II report will contain detailed assessment and management of environmental impacts."

Jan 1, 1981

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 Nima Nabavi

Shovels and excavators have significant blind spots due to their large sizes, increasing the chances of collision with other surrounding equipment such as haul trucks, loaders, and dozers. While a camera surveillance system is very useful in preventing collision, it can benefit from two additional features: (i) the ability to display the distance of the closest object within the view, and more importantly (ii) the ability to warn the operator if objects are getting too close. After a comparison between few different technologies, it is explained how these features can be provided by integrating rugged pulsar radar sensors with a camera system. The specific radar technology is already field proven in the harsh mining environments. Motion Metrics International Corp. has developed this exact product, which combines its 4-camera surveillance system (ViewMetricsTM) with a series of rugged radar sensor elements, named ViewMetricsTM-Radar. The radar system employs intelligent CAN bus communication to reduce wiring, hence improving hardware reliability with built-in troubleshooting features. A USB connection is the only hardware bridge between the radar sensors and the embedded computer. As such, an existing ViewMetricsTM system can be easily upgraded to ViewMetricsTM-Radar. As addition of new interfaces to the cab could result in operator distraction, this paper explains how ViewMetricsTM-Radar reduces distraction compared to other radar collision prevention systems.

Oct 1, 2009

By A. Desbiens, M. Maldonado, R. del Villar, Aguilera. R.

This work details the application of a multiple model approach to estimate frother concentration in flotation processes. The methodology consists of identifying a set of linear dynamic models representing the effect of gas rate on the collection-zone gas holdup at different known frother concentrations (calibration step). An adaptive law is then obtained using Bayes' rule to evaluate the conditional probability that each model represents the observed system behavior. In this way, a frother concentration estimate is calculated as a weighted sum of model probabilities and their associated (known) frother concentrations. Experimental results conducted in a two-phase system using Dowfroth250C are promising. Modeling and analysis for MIBC frother are also provided.

Jan 1, 2009

By A. Atrafi, L. Barroilhet

The top size of particles in the flotation of potash ores, which can be as large as 4 mm, exceeds by far the top size in other flotation plants. It is then understandable that while long chain amines are used in the flotation of fine fractions (below 0.8 mm) of potash ores the coarse particle flotation also requires an extender oil. While new and very promising fluidized-bed flotation machines (e.g. HydroFloat) constitute a significant development in the flotation of coarse particles, in the area of extender oils, as reviewed in 2007 by Strathdee, Gotts and McEachern, there have been no new developments to replace the industry standard asphaltene-based carcinogenic extenders. This situation first of all results from the experimental problems that arise when water-soluble minerals like sylvite are to be tested in saturated brine. Both oils and longchain amines are water/brine insoluble. The oil with the amine dissolved in it can however be emulsified and then used as an extender oil. Such oil droplets must wet KCl particles and the emulsion must be stable to avoid handling problems. In this paper we test the use of the phase inversion technique as a method of studying wettability of KCl particles by the oil in saturated brine, and the effect of amine dissolved in this oil on the wettability. The results show that this relatively simple technique can be used to characterize the wettability of fine KCl particles by the tested oil and to determine the effect of added amine on it, and so it can be useful in selecting proper extender oils.

Jan 1, 2016

By 13409, B. Arjang

"Ground stresses are one of the significant factors in the context of rockbursts and underground instability at some hard rock mines in Canada. Overcoring strain relief measurements using triaxial strain cells were performed at several mine sites to provide stress data for stability evaluations and mine design. Pre-mining stress determinations carried out at depths between 60 m to 1890 m resulted in the following average stress gradients:Maximum horizontal stress, s Hmax = 8.18 + 0.0422 MPa/m depthMinimum horizontal stress, s Hmin = 3.64 + 0.0276 MPa/m depthAverage horizontal stress, s Ha = 5.91 + 0.0349 MPa/m depthVertical stress, a; = 0.0266 ± 0.008 MPa/m depthThe maximum and minimum horizontal compressive stresses, with an average ratio of J.75 ± 0.45, prevail in east-west and northerly directions, respectively. Horizontal compressive stresses in excess of vertical overburden load were determined, indicating large variations in ratios to a depth of about 1000 m with decreasing trend toward depth.From present data, a particular regional zoning for the magnitude and direction of horizontal stress fields cannot be outlined.A common feature at mines with near vertical orebodies is that the maximum horizontal stress acts perpendicular to strike while the minimum horizontal stress is aligned on-strike. The vertical stress components approach the gravitational overburden load."

Jan 1, 1991