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By A. Ismail

"The paper takes its material from three peat mining and power project feasibility studies sponsored by CANMET and conducted by Montreal Engineering Company Ltd. in the years 1976 to 1980. The role which peat may play in the Canadian energy prospectus is outlined, estimated and measured fuel peat resources are tabulated, and the economic and technical feasibility of mining peat for power generation is reviewed Recommendations are made for future work, and construction and disbursement schedules are developed for a combined peat mining and power generation project. The relationship between the mining of moss and fuel peat is discussed.IntroductionWhereas moss peat has long been produced in Canada, and exported for horticultural use , the underlying fuel peat has received little attention until fairly recently.In the seventies, however, the deepening oil crisis spurred Canadian interest in Irish, Finnish and Russian experiences in the utilization of fuel peat. Among others, Energy, Mines and Resources Canada had long been alive to the possibilities which indigenous peat offers, and in 1976 the Canada Centre for Mineral and Energy Technology (CANMET encouraged a proposal from Monenco to carry out a preliminary study and submit a report on the "" Assessment of Canadian Peat as an Alternative Fuel for Power Generation"". The report was submitted in April 1977. This was the first of a series of studies, and the authors of this paper were involved in its preparation.The escalating price of oil and the increasing problem of relying on its availability have combined to make alternative fuels more attractive. Peat, like other fuels previously uneconomic because oil was cheap, is now progressively gaining in viability. In addition to these factors, the utilization of peat has the following advantages: improvement in the country's balance of payments, by virtue of burning an indigenous fuel;creation of local employment for the mining of peat; improvement in land utilization;peat is a relatively clean-burning fuel, with low sulphur and ash contents."

Jan 1, 1980

By Masaru Kato

The plated gold being used by the electronics industry can be broadly classified into two categories: soft gold and hard gold. Soft gold is used for circuit metallization and for bonding semiconductor chips, while hard gold is indispensable as the contact material on electrical connectors, electromechanical relays, and printed circuit boards. The traditional baths from which to plate soft gold as well as hard gold contain the cyanide complex, [Au(CN)2]-, as the source of gold, which liberates free cyanide ions during the plating. The free cyanide is not only highly toxic but also attacks photoresists used to delineate circuit patterns and bonding pads. For these reasons, non-cyanide baths are in use to plate soft gold, whereas hard gold can be plated only from cyanide baths at present. In this presentation, the current status of both electrolytic and electroless non-cyanide processes for plating soft gold will be reviewed.

Oct 1, 2003

By S. Suzuki, C. Tokoro, S. Owada, T. Sakakibara

Acid mine drainage (AMD) has been actively treated by neutralization from about 80 abandoned or closed mines in Japan. More efficient and cost effective treatment processes has been demanded for AMD due to the government investment of billions of yen every year to protect the environment from these discharges. In this study, quantitative modeling was conducted for actual AMD to predict pH or residual concentration of toxic elements after neutralization/co-precipitation process. Simple chemical equilibrium calculation was not adequate for quantitative prediction of pH after neutralization, because residual concentration of major elements of AMD, such as Fe or Si, could not be quantitatively calculated. When oxidation rate of Fe(II) to Fe(III) and precipitation rate of kaolinite were added to the model, quantitative prediction of pH and Fe or Si concentration was achieved. Surface complexation at the interface between hydroxide such as ferrihydrite or aluminum hydroxide and AMD was the most important mechanism for removal of dilute toxic ions. When surface complexation model at the interface of ferrihydrite was added to the model, residual As (V) and Pb (II) concentration after neutralization/coprecipitation process was successfully calculated. On the other hand, surface complezation model of aluminum hydroxide was also necessary for quantitative prediction of residual Zn(II) concentration after neutralization/co-precipitation process.

Jan 1, 2014

By O. Kodym

The paper has focused on possibilities of interconnecting information sources concerning monitoring & control of mining industry technical processes (TP), and the related safety hazards. The key issue is the comprehensiveness of the information presented to users. Information can be presented by virtual reality means, when the seemingly true presentation of the production process scene along with user friendly presentation of related information is available. The user in its role of a process supervisor is not only a mere scene observer but, thanks to the interactive functions of virtual environment, he participates in the scene of his control. As such his control and management abilities increase because he can absorb, more easily understand and asses the information provided.

Aug 1, 2013

By Nick Vayenas

This paper discusses the application of a commercially available state-of-the-art PC discrete-event simulation modeling software, called Promodel, for simulating a typical underground mine hoist system in the Sudbury mining region, in the province of Ontario in Canada. The reasons for using Promodel as a two-dimensional simulation development tool is its simplicity in use and its capabilities to provide enough flexibility to meet the modeling requirements of a mine hoist system. General information of a mine hoist system was collected for building the model. Example of the model?s output is also presented. The application of Promodel in underground mining offers a powerful, two-dimensional simulation environment in an affordable price for mining engineers to analyze and study operational problems. This hoist simulation model is an intuitive demonstration of the mine hoisting elements and the operational logic of the hoist, based on which optimization of the entire mine system materials flow can be considered as part of a mine cycle management feasibility study.

Oct 1, 2009

By C. D. Smith

Numerous studies have shown the potential of air rate profiling to significantly improve the flotation performance of a bank of cells. To date many profiles have been implemented; balanced, increasing, decreasing and combinations of these. Previous work has typically shown using an increasing air rate profile, where the air rates are increased proportionally to each cell down the bank, yields a higher grade for a given recovery compared to other profiles. Air rate profiling can then be thought of as having two distinct components; determining the correct distribution of a given volume of air and, perhaps more importantly determining the correct total volume of air to add to the bank. To date no method for this second component has been established. In an alternative technique the air rate to each cell is adjusted in order to optimise the air recovery from that cell. Air recovery is the fraction of the inlet air which overflows the weir of a cell as unburst bubbles. The peak in air recovery (PAR) is a robust measurement that indicates optimal performance for the operating conditions in the cell, and sets the PAR air rate. By doing this for each cell in the bank, the optimal total air rate to the bank and the optimal distribution of that air can be simultaneously determined. In this study plant trials evaluated different air rate profiles, and profiling based on PAR. The total air rates to the bank for all profiles tested were approximately equal, allowing direct comparison. The results showed that the highest cumulative mineral recovery was achieved by operating at air rates which gave the PAR for each cell down the bank. Different distributions of the same total air rate to the bank gave the same cumulative upgrade ratio, but lower cumulative recoveries. In this study, the increase in cumulative mineral recovery, at the same upgrade ratio, was more than 33%. Peak in air recovery (PAR) based optimisation of air rates to banks of cells and to the individual cells has been shown to significantly improve flotation performance as it simultaneously determines the optimal air rate to the bank, and the optimal distribution of that air.

Jan 1, 2009

By R. S. Adhikari

This paper presents an innovative computer vision method for condition assessments of bridges with multiple defects in bridge elements using digital images. This work utilizes 3D model of existing bridges and overlays digital images on 3D model to simulate on-site visual inspection. The analysis of element condition index (ECI) of bridges requires information about the severity and extent of defects in elements. In general, ECI is evaluated manually during routine bridge inspection considering the severity of dominant defects. The evaluation of ECI with multiple defects needs to be addressed with consideration of dominant defect as well as the interaction among defects. However, Image-based quantification techniques largely depend on geometry of objects (i.e. shapes). Shape vectors of a given object change as they are translated, rotated, and scaled with different magnitudes. This work considers shape preserving algorithms such as, affine and projective transformation for proper image alignment. Semi-automated approach for detection and quantification of concrete distress such as cracks and spalling are considered for the defects analysis. The proposed methodology ensures the consistency in reporting ECI and eliminates the shortcoming of traditional approaches.

Aug 1, 2013

By F. Q. Su

Underground Coal Gasification (UCG) is a promising environmentally acceptable clean-coal technology. A typical UCG system has two wells drilled from the surface into a coal seam with some separation of injection from production. The wells are connected underground by various linking techniques. After creating a combustion reactor in an underground coal seam, air and oxygen flow through the injection well. Heat energy and gases are collected from the production well. As gasification progresses, the combustion reactor is moved along the linking hole. Using this process, the fracturing activity inside the coal seam serves an important role for enlargement of the gasification zone because the surface area oxidization increases continuously by coal cracking. For effective coal gasification, fracturing activity must be controlled. Moreover, excess fractures inside the coal seam and surrounding rock can induce gas leakage, underground water contamination, subsidence, etc. Therefore, monitoring and control of fracturing activity in underground areas constitute key technologies for efficient and safe UCG. To monitor fracturing activity, we conducted laboratory and small-scale field experiments of UCG using acoustic emission (AE) measurements. UCG model tests were conducted for linking and coaxial types UCG models. Coaxial UCG systems are compact and are anticipated for application in underground coal seams having a complex geological structure. The UCG model consists of a coal block molded in a steel canister (20 liter capacity) with heat-resistant mortar, with a linking hole or a coaxial-hole passing through the coal block. During coal combustion, coal temperatures, production gas contents, and AE activity were monitored under the control of injection-air and oxygen flow rates. Results show that the combustion propagated inside the specimen along the linking hole. Many AE events were generated during coal combustion. The AE activity was related closely to temperature changes inside the coal block. This AE generation apparently results from crack initiation and extension around the coal combustion area under the influence of thermal stress. However, comparing the results from UCG models of linking and coaxial types, the gasification of the linking type model showed an average calorific value as high as 11.3 MJ/m3. The coaxial type yielded an average calorific value of produced gas as only 5.79 MJ/m3. In the coaxial type of UCG model, the combustion region was limited to the area around the coaxial hole. The AE activity was lower than in the linking type model. For small-scale UCG field experiments, linking and coaxial types were tested at an open pit coal mine in Hokkaido, Japan. Using a linking type UCG, 58.2 kg coal was processed in 39 h, with the calorific value estimated as 11 MJ/m3. However, the coaxial type UCG processed 7.0 kg coal in 9 h, yielding an estimated calorific value of 6.0 MJ/m3. These tendencies resemble those of results of laboratory UCG experiments. Results of these experiments demonstrate that AE monitoring is a useful tool to evaluate combustion reactors for efficient and safe UCG systems. To develop a coaxial UCG system, results show that fracture control around combustion reactors is indispensable.

Aug 1, 2013

By R. M. T. Raja Ismail

Shipping and stevedoring industry is going to witness a massive increase in the amount of containers to be handled while land constraints become more critical. Offshore transfer operations hence offer a preferable solution to deal with the surge in cargos rather than to expand the port outwards. Recently, there has been increasing research interests on offshore crane automation. Suspended cargos in a ship-mounted crane system are caused to swing due to the vibratory motion of the ship induced by ocean waves, which can lead to collision between cargos and deck. Therefore, it is vital for offshore crane systems to satisfy rigorous requirements in terms of safety and efficiency. This paper presents the modelling and control development for offshore boom crane systems. A second-order sliding mode control law is proposed for trajectory tracking and sway suppression control, making use of its capability of actuator chattering alleviation while achieving high tracking performance and preserving strong robustness. The asymptotic stability of the closed-loop system is guaranteed in the Lyapunov sense. Simulation results indicate that the proposed controller can significantly reduce the effect of disturbances coming from gusty waves and other dynamic loadings.

Aug 1, 2013

By Jonathan Peck, Jim Gray

"With the implementation of more advanced monitoring, control and locating systems in surface mines, there is an ever increasing need for their mine-wide integration toward achieving over-all optimization. AQUILA Mining Systems Ltd. is developing the basis for a comprehensive real-time monitoring, control and information system called the Total Mining System or TMS. This system is being designed to address both current and future needs of open pit mines toward improving productivity and minimizing costs, through better two-way information flow between each component in the operation. At a basic level, feedback from equipment and process monitoring will enable decision making to be based on quantitative, on-demand information, thus permitting proactive rather than reactive planning. Dynamic planning would be a valuable tool as market conditions fluctuate, equipment fleets age and variations in the grade, quality, geometry and hardness of the mined material all contribute to either changing production targets or levels of achievable performance. Such a capability could be implemented within the next two years.At a higher level, and within five years, autonomous operation and/or real-time supervisory control of mobile and stationary equipment in open pit mines will be achieved. A discussion is provided in regard to the development and implementation of an autonomous haultruck and blasthole drill, to demonstrate the need for such a system.This paper outlines a preliminary program for the design, development and implementation of this system, primarily in relation to high-level communications and its role in the future automation of open pit mobile equipment."

Jan 1, 1995

Presentation Plan Hoist ropes ?Importance ?Mandatory and routine Inspections Continuous monitoring of wire ropes for mine hoisting ?Why a continuous monitoring of mine hoisting ropes.? ?Description of the ??Contiscan?? monitoring system ?Information data gathering Advantages of the ??Contiscan?? monitoring system ?Visual rope inspection on daily basis ?Monthly inspection ?Payload capacity flexibility and potential increase for deep mining operations. ?Periodical inspections by external experts ?Importance of the costs associated with hoisting production shutdowns. Commercialization and availability

Aug 1, 2013

By R. V. Kumar, F. Tailoka

In order to use ZnO laden dust as a possible desulphurization reagent, it is important to evaluate thermodynamics of the Zn-O-S system. At temperatures greater than 1450 K, there is an uncertainty in the thermodynamic data for the reaction of zinc with sulfur to form Zinc sulfide. In this work, the standard free energy has been determined using an electrochemical cell: Pt, Mo, MoO2/YSZ/ZnO, ZnS, S02, Pt., between 1198 and 1602 K. AG° varies from -145,880 to -88,100 J (± 2500) , with a phase change to ZnS (g) by sublimation occurring between 1450 and 1460 K. This is supported by thermogravimetric analysis which shows about 80% weight loss in ZnS from 1273 to 1473 K. Feasibility reactions were also performed and confirmed that ZnS (g) is formed when ZnO reacts with FeS (1473 to 1653 K) or with Fe-Csat-S(1473-1673 K). There is therefore potential for the utilization of ZnO laden waste as an additional or alternative reagent for desulfurisation.

Jan 1, 2004

By T. Yameogo

Many ideas, tools, technologies, and methodologies are believed to have staked their claims on the future of mining. For example, automation is strongly positioned as the platform within which mining will be practiced. A subset of automation ? intelligent mining ? will add some smart interactions between machines, technologies, the rock, and the environment. The future also calls for an improved approach to sustainability and corporate social responsibility. Mines of the future are dreamed of to be more ethical and more balanced. They will boast optimized designs, integrated value and supply chains, produce less waste, recycle and reuse, and will require less energy to operate. Then, what about the people that will operate this optimized ecosystem? How is the education system teaching the operators of the mines of the future? What kind of a future should mining education foresee to prepare the workers appropriately? In recent years, the shortage of skilled labor for mines around the world has created a tough competition to attract, retain, and train the very people without whom mining will cease to exist. In Australia, Canada, and the United States in particular, the war for talent has resulted in higher-than-usual labour costs. Such costs have dented the unit costs of many mining businesses. Concomitantly, mining contractors? and consultants? prices have increased to reflect the escalation of labour costs across the value chain. From labourers to engineers, from juniors to seasoned professionals, the increase in compensation is unprecedented. Yet, the shortage is still hurting the industry, and the high calibre candidates continue to be rare gems. The industry has been implementing aggressive solutions that include the increased hiring of skilled immigrants, the training and recruitment of minorities, and the retaining of near-retirement experienced employees. Public relation campaigns about the benefits of embracing careers in mining are also common. The CIM has also devoted a ?M4S? section to its pan-Canada meetings to educate the public, especially the youth, about the importance of the mining industry for Canada. Moreover, mining associations and universities are enticing students? enrolment through scholarships and financial support. Still, the balance between quantity and quality of workers can be discussed. This paper intends to discuss the present state of mining education as an essential part of the future of mining. The authors brush the picture of the education of miners, technicians, and engineers, against the backdrop of the technology-advanced mines of the future.

Aug 1, 2013

By Marcel Vallée

"Abstract - Traditionally, the emphasis in ore and reserve inventory has been to provide fairly simple definitions and presentations for reporting to shareholders and the investing public. The recent introduction of the mineral resource category aims to take into account the "part of the deposit that cannot yet be produced or extracted legally and profitably." Recent proposals still place insufficient emphasis on relating resource/reserve reporting definitions more closely to the needs of mining and exploration operators for the estimation and inventory of these basic material assets.In most schemes, significant ambiguities and shortcomings remain. These concern the potential economic interest of resources, the concept of continuity which is fundamental to the estimation of volumes, mass and grades, the objectives of the production feasibility study and the requirements of the geology, engineering and economic appraisals leading to it, and the "availability" of the permits required to start mine development. Up to now, no industry-wide formal consensus has yet been reached for any of these steps, nor for reconciliation between successive statements.A resource/reserve inventory scheme is presented here that is based on ISO 9000 principles and the Australasian system. Explicit criteria and transition points are proposed to define resource and reserve. Similarly, appropriate criteria are proposed to classify the three mineral resource and two ore reserve categories, based on geological and value continuity and on the objectives of the feasibility study. This scheme offers a way to develop ISO 9001 certification of resource/reserve estimation procedures for mining operations and supply exploration companies with an appropriate inventory system, to allow better information for the shareholders and the investing public.Résumé - L’objectif des inventaires des minerais et des réserves est, depuis le début du siècle, de fournir des définitions simples et d’ordre général visant les actionnaires et le public investisseur. L’introduction d’une catégorie de « ressources minérales » fournira un cadre tenant compte de la "portion d’un gisement qui ne peut encore être extraite ou exploitée légalement et à profit." Cependant, les propositions récentes de systèmes d’inventaires ne comportent pas des définitions des ressources et réserves qui tiennent compte suffisamment des besoins des opérateurs en exploitation et en exploration minière.La plupart des systèmes comportent des ambiguïtés et des carences. Citons la susceptibilité d’exploitation commerciale des ressources, la continuité qui est au centre de l’estimation des volumes, masses et teneurs, les objectifs de l’étude de la faisabilité de la mise en production, le niveau requis des travaux de géologie, d’ingénierie et d’économique qui y mènent, ainsi que la disponibilité des permis dont dépend la mise en production. Il n’y a jusqu’à maintenant aucun consensus dans l’industrie sur ces points, ni sur des procédures de réconciliation entre les estimations successives.Le système d’inventaire des ressources/réserves proposé ici s’appuie sur la structure ISO 9000 et le système australien. Des critères et des points tournants explicites sont établis pour définir les ressources et les réserves. De même, les définitions des trois catégories de ressources et deux catégories de réserves, s’apparent sur la continuité de la géologie et des teneurs et sur les objectifs de l’étude de la faisabilité. Ce projet offre une voie pour développer les critères de la certification ISO 9001 pour les opérations minières, tout en fournissant un système approprié d’inventaire aux compagnies d’exploration, pour mieux informer les actionnaires et les investisseurs potentiels."

Jan 1, 1998

By David Christensen

The long-term performance of dry covers is being examined in a research study funded by the International Network for Acid Prevention (INAP). The study was separated into two phases. The two main components of Phase 1 of the study were the identification and research of the processes affecting the long-term performance of dry cover systems and an examination of available numerical models for simulation of long-term cover performance. Identification and research of the physical, chemical, and biological processes affecting long-term performance showed that cover performance could be related to the change in the saturated hydraulic conductivity of cover material, the change in the soil-water characteristic curve, and the physical integrity of the cover system. Seven numerical models were examined to evaluate their effectiveness in predicting the long-term performance of cover systems. VADOSE/W (Online Help v1.01, 2002) was selected for use in cover system modeling in Phase 2 of the project. Phase 2 of the research study is currently in progress and involved the selection of five mine sites with a minimum of three years of performance monitoring data for analysis of cover performance. Two of the mine sites will be analyzed with the two-dimensional VADOSE/W numerical model. In addition, field saturated hydraulic conductivity tests were completed at three mine sites to investigate the change in field hydraulic conductivity of the cover system materials. The objective of the field testing program was to evaluate changes in hydraulic conductivity of cover material with time. Measurements of field hydraulic conductivity were completed with a Guelph permeameter and a pressure infiltrometer at three sites. The field hydraulic conductivity data was used to evaluate whether a change in this key material property had occurred over time. Field observations and the historic performance monitoring data provided the necessary information to develop hypotheses as to the likely processes that led to any change in field hydraulic conductivity. This paper will briefly summarize the research completed in Phase 1. The remainder of the paper will focus on the field testing program completed to measure the field hydraulic conductivity of constructed cover systems.

Nov 1, 2002

By Marcotte P.

Introduction Pneumatic jackleg rock drills are commonly used in underground mining operations. These tools are known to expose their operators to hand-arm vibration levels in the order of 20-35 m/s2 weighted (Wh). Thus, the majority of the workers who have cumulated several years of jackleg rock drill operation are affected by related health problems such as Raynaud's syndrome or carpal tunnel syndrome. Up to now, no efficient personal safety device was available to protect pneumatic rock drill operators against hand-arm vibration (HAV). To address this problem, an anti-vibration handle prototype for jackleg drills has been developed in a previous study. Then, a multi-partner project was launched to refine the prototype and commercialize an effective anti-vibration handle for pneumatic rock drills.

Feb 1, 2008

By R. Brough

"Over 25 years ago, SKEGA pioneered the use of rubber linings in grinding mills and rubber is today widely accepted and almost standard material chosen for Regrind - and Secondary Hills. There are, however, only a few Primary Hills in operation with ""solid"" rubber linings because available materials and designs are often not cost efficient in comparison with steel alloys on a Cost per ton basis and/or downtime for liner replacement would be to a high.In other words, solid rubber has limits as any other material. However, 'SKEGA started to think, why not try to use the best properties of rubber as well as steel and combine the two materials together.Nearly 10 years ago SKECA started to test this concept in Rod Mills. A steel cap was vulcanized on to the leading face of the lifter bars, to be installed close to the feed end head (fig. 1)."

Jan 1, 1988

By W. D. Gould, F. Goodazi, W. F. A. Duncan, A. G. Mattes

A biological treatment system designed to passively remove high concentrations of metals from leachate collected from a landfill near a large integrated zinc lead smelter has been in operation intermittently for the past five years including winter time operations. High metal removal efficiencies in the system were achieved. After 729 days of operation and treating over 8 million L of water the original anaerobic bioreactor constructed in 1997 was taken apart and rebuilt. The deconstruction of the bioreactor allowed systematic sampling at all depths of the biological matrix. Samples were analyzed for metal, S and TOC concentrations; as well bacterial populations were determined. Results of this sampling procedure are examined and compared at various depths within layers and between layers using one-way ANOVA and linear regressions. Metal concentrations were positively correlated with sulphur and negatively with total organic carbon. This is in concurrence with a model of biogenic precipitation of metal sulphides.

Jan 1, 2004

By D. B. Langford, R. Hart

"This paper presents an overview of the state-of-the-art in industrial and utility power metering and control systems with particular emphasis on Digital Power Meters and Power Demand Controllers.IntroductionModern micro-processor technology, combined with very fast, high accuracy analog to digital converters, is rapidly allowing economical, digital power instrumentation systems to replace the traditional electro-mechanical meters and equipment previously used for instrumentation, control and protection in industrial power systems. Consequently, instrumentation and Supervisory, Control and Data Acquisition (SCADA) systems that were only practical for the very large utility or user are now available to smaller utilities and users. The information available includes sequence of event recording, trend logging, energy management cost allocation and automated load control, among others. The heart of any power monitoring system is the Digital Instrumentation Package (DIP) . These ""DIP's"" include Digital Power Meters (DPM's) and Power Demand Controllers (PDC's) as well as other specialized instrumentation packages such as Mini RTU's."

Jan 1, 1991

?Introduction to the Delphi Group ?Why is carbon important to your organization ?Key elements of a carbon management strategy ?Inventory ?Risk & opportunity scan ?Mitigation options and financial mechanisms ?Identify targets and develop policy ?Communication and improvement ?Manage for success

May 1, 2009