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By B. Wasmund

Success in implementing new technology for metallurgical processes is not a foregone conclusion: This paper includes a survey of 23 new technology-based metallurgical plant start-ups, in which the authors have identified 7 successes, 9 difficult start-ups, and 7 failures. Success is defined not only as meeting the schedule and budget to the end of mechanical completion; the key goal is a fast ramp up to the full design production level, with minimum plant and equipment modifications required after start-up. This paper sets out the key factors that underlie achievement of a quick production ramp up curve, as determined from the authors? project experiences and a quantitative analysis of over twenty metallurgical plant start-ups, both pyrometallurgical and hydrometallurgical. Thorough test-work and pilot plants, plus appropriate scale-up to the full commercial plant, are key determinants of success in implementing new technology in metallurgical processes. Another critical factor is the number of new elements and their interactions. Project phasing is also particularly important for new technology projects, with appropriate review after each phase to develop a risk mitigation plan for the subsequent phase. New technology projects need committed champions to advance the project in the face of sceptics, but also require dispassionate and unbiased experts to ask the hard questions. As a project evolves, it is important to periodically question the appropriateness of assumptions, as well as to re-assess the relevance and completeness of data from test-work / pilot plants / industrial analogues. Sufficient human and financial resources are required to complete the often arduous implementation phase. During the ramp-up period, the operation generates little positive cash flow; however, significant expertise and capital are required for the de-bottlenecking projects that are often necessary to reach the plant?s design output level.

Jan 1, 2011

The resource sector is conservative industry and people are resistant to change. The methods and procedures used to implement changes in process plants ultimately determine the success of such changes. The financial managers have a large say in where money is spent and the technical personnel must justify the cost and benefits for any expenditure. There are also others who believe it canÆt be done û æwe tried thatÆ. Implementing change needs a æChampionÆ who can assess the risks, plan, define the objectives and scope, set the goals, determine the key performance indicators (KPIs) and stay focused. This also requires preparing a budget and schedule and measuring against this. Contract management, reports and reviews are part of the implementation. Several case studies are given as examples of the implementation of process design changes to highlight the critical aspects involved.

Jan 1, 2009

One of the strategies introduced within Pasminco Mining to survive low commodity prices is to formally implement a `Quality Education System'. The net result has been a consistent approach to quality within and across mine sites. This `quality system' has been adopted in the technical computing environment and the immediate benefits have been: ò A clearer understanding of the systems, processes and relationships that involve technical computing. ò A re-focussing on customer (user) requirements. ò Inclusion of managers as customers with their own requirements of performance and quality, in addition to access to Executive Information. ò New ways to measure the `performance' of a technical computing environment which includes using maintenance costs. Observations are that there is an overlap between `traditional' information technology (IT) methodologies and quality systems being put in place in the broader workplace. This overlap is most apparent in the area of analysing customer requirements. In the IT environment customers are viewed as users, and their requirements determined by undertaking a requirements analysis. A data flow diagram traditionally used in the IT environment and not as a tool in quality systems, has been used in a novel manner to help identify the customers of the technical computing department. It has also been useful in illustrating the work processes and relationships between the entities in this diagram and in directing the future initiatives needed to fulfil the customers' changing requirements.

Jan 1, 1995

The information in this document has been prepared as at February 16, 2011. Certain statements contained in this document constitute ?forward-looking statements? within the meaning of the United States Private Securities Litigation Reform Act of 1995 and forward looking information under the provisions of Canadian provincial securities laws. When used in this document, the words ?anticipate?, ?expect?, ?estimate?, ?forecast?, ?will?, ?planned?, and similar expressions are intended to identify forward-looking statements or information. Such statements include without limitation: statements regarding timing and amounts of capital expenditures and other assumptions; estimates of future reserves, resources, mineral production, optimization efforts and sales; estimates of mine life; estimates of future internal rates of return, mining costs, cash costs, minesite costs and other expenses; estimates of future capital expenditures and other cash needs, and expectations as to the funding thereof; statements and information as to the projected development of certain ore deposits, including estimates of exploration, development and production and other capital costs, and estimates of the timing of such exploration, development and production or decisions with respect to such exploration, development and production; estimates of reserves and resources, and statements and information regarding anticipated future exploration; the anticipated timing of events with respect to the Company's minesites and statements and information regarding the sufficiency of the Company's cash resources. Such statements and information reflect the Company's views as at the date of this document and are subject to certain risks, uncertainties and assumptions, and undue reliance should not be placed on such statements and information. Many factors, known and unknown could cause the actual results to be materially different from those expressed or implied by such forward looking statements and information. Such risks include, but are not limited to: the volatility of prices of gold and other metals; uncertainty of mineral reserves, mineral resources, mineral grades and mineral recovery estimates; uncertainty of future production, capital expenditures, and other costs; currency fluctuations; financing of additional capital requirements; cost of exploration and development programs; mining risks; community protests; risks associated with foreign operations; governmental and environmental regulation; the volatility of the Company's stock price; and risks associated with the Company's byproduct metal derivative strategies. For a more detailed discussion of such risks and other factors that may affect the Company?s ability to achieve the expectations set forth in the forwardlooking statements contained in this document, see the Company's Annual Report on Form 20-F for the year ended December 31, 2009, as well as the Company's other filings with the Canadian Securities Administrators and the U.S. Securities and Exchange Commission. The Company does not intend, and does not assume any obligation, to update these forward-looking statements and information. Marc Legault, a Qualified Person and the Company?s Vice-President, Project Development, reviewed the technical information disclosed herein. For a detailed breakdown of the Company?s reserve and resource position see the February 16, 2011 press release on the Company?s website. That press release also lists the Qualified Persons for each project.

May 1, 2011

By Daniel D. M. Adams

In 2004, Rio Tinto started a major project to implement Mine Monitoring and Control (MMC) systems worldwide. A detailed selection processes was undertaken and migration to a standard system was started. Today systems are operating around the world and serve as the core of to many business processes. Implementations include highly union areas, large mines, centrally managed mines, and remote areas. Each implementation has unique challenges but all are working towards the common goal with common systems. This paper reviews two projects that Rio Tinto has deployed in diverse conditions. The projects are the Rossing Uranium upgrade from the original Wenco system to the common standard and Iron Ore of Canada?s general technology upgrade. Also discussed is the future of mining at Rio Tinto, specifically the drill automation projects, and how it is utilizing the common standard MMC systems.

May 1, 2010

Automation Defined ?Using self-operating equipment to reduce human exposure to the mining environment and routine or repetitive work.?-Atlas Copco Terminology: ?Manual Operation ?A vehicle being operated by a person ?in the cab?. ?Radio Remote Control (RRC) ?A vehicle being physically operated by a person through a Line Of Sight (LOS) or Video-Remote equipment. ?Tele-Remote Control ?A vehicle being physically operated by a person at an operator station which is not necessarily located near the vehicle?s working area. ?Autonomous Operation ?A vehicle under self control with the possibility of human supervision and override.

Oct 1, 2010

By J. R. Addison

Commissioned in September 1987, the Phelps Dodge Morenci, Inc. (PDMI) Central Electrowinning (EW) Tankhouse bas undergone two major expansions in its eleven-year history. A third tankhouse renovation, which began in November 1998, entails complete conversion of the 548-cell facility from a copper starter sheet based operation to Mt. Isa Process stainless steel mother blank technology. This paper outlines the operating history of the Central EW Tankhouse and reviews the conversion process, the rationale that led PDMI to undertake this project, and describes various design optimizations which have been implemented during the conversion.

Jan 1, 1999

By J. Wickens

"Campbell Mine is dedicated to quality management in the form of a Continuous Improvement (CI) Operating Philosophy. This paper discusses that philosophy, why and how it is being implemented in the milling facility, and some of the challenges experienced to date. Examples of mill CI team projects and results are described. This paper describes practical experiences for those who are considering or are in the process of adopting a CI operating Philosophy.INTRODUCTIONCampbell Mine is 100% owned and operated by Placer Dome Canada Ltd. The mine is located in Balmertown, Ontario approximately 300 km northeast of Winnipeg, Manitoba. Campbell Mine has produced over s,000,000 ounces of gold since commencing operation in 1949. The operation is profitable and continues to be a major contributor to the gold production of Placer Dome Inc.At Campbell Mine, the concept of Continuous Improvement (CI) is being implemented to make further improvements to safety, quality, productivity, and subsequently profits. CI is not a ""program"". It is a way of doing business that concentrates on improving the system rather than finding fault and being resigned to the status quo.CI focuses on involving all employees in the decision making process and tapping their expertise to improve every facet of the business. In the past, many solutions were simple ""band-aid"" fixes treating the symptom, only to see the problem resurface again. With CI, solutions endeavour to address the root cause of problems and eliminate them permanently. Another primary goal is to eliminate unilateral decisions that benefit a small group but have a negative effect on the whole system."

Jan 1, 1995

By Brien A. Perry, Art Wiebert

"Many organizations which have implemented Total Quality Management (TQM) are finding that the process has either stalled or is not working so well as originally envisioned. This can be particularly evident in an engineering environment where the uniqueness of engineers and their particular culture has not been adequately considered. Winning the commitment of a highly educated group ojprojemnnJJ1s to the TQM concepts, which are often initially 5W2 as too simplistic poses special challenges.Successful TQM implementations are found among technical groups where employees have significant input into creating the new work culture, feel empowered to make changes and are well trained in teamwork. A coach who is knowledgeable in implementation problems can, when working closely with the technical teams, help them circumvent obstacles and guide them successfully through the difficult early phases. The remaining key ingredient for success is supportive management which leads the change and is both informed and appreciative of the accomplishment being made.This Paper is based on first-hand experience with common problems and results encountered in implementing TQM in an engineering environment. Described in the paper are ways of avoiding these problems through awareness of the unique nature of engineering groups, implementation planning, just-in-time training and coaching people in the TQM process. The paper concludes with a focus on the opportunities and results from a successful implementation. These opportunities and results include the benefits each engineer can realize through process thinking, empowerment and teamwork."

Jan 1, 1995

By Daniel Kim, Ari Rantala

Efficient on-line monitoring of electrolytic cell performance in copper electro-refining has been challenging due to the need for complex electrical measurement systems and the management of the enormous volume of data. Based on Kennecott Utah Copper's innovation Outotec has developed a novel and innovative electrolytic cell monitoring system called CellSense™ System. As the system is based on self-powering from bus bars, wireless communication, on-line adaptive modeling and easy to access information and alarming, traditional obstacles of electrolytic cell monitoring are eliminated. With cell voltage and electrolyte temperature measurements, CellSense System enables real-time cell performance discovery and early reaction to critical production or quality disturbances such as short-circuiting, flow blockages, cold cathodes or electrolyte temperature excursions. During the past few years the system has been delivered to over 3500 commercial cells. In this paper the largest CellSense™ System ever delivered and recently adapted by Kennecott Utah Copper with 1412 cells monitored on-line for high tankhouse performance, cathode quality and optimized operator work flow is presented. Early results and benefits are discussed.

Jan 1, 2012

By H. Gurgenli

Mining companies require accurate short-term mining forecasts to meet budget targets and customer needs. Challenging mining conditions along with employee turnover and lack of standard geologic modeling and mine planning processes can result in time-consuming and inconsistent mine plans. Documentation and automation of the processes involved in mine planning, as well as proper software utilization, are critical in overcoming these challenges. This paper discusses the steps involved in achieving an optimized mine planning system to accomplish productive and cost effective operations. In addition, a case study is included to describe the process of implementing a semi-automated system whereby the geologic model and mine scheduling database are updated monthly to incorporate changes in geology in a relatively complex open-pit coal mine. This case study proves that the ability to update geologic models based on the latest information gathered from production drilling and mining activities can greatly enhance the ability to accurately predict short-term mining production.

Jan 1, 2011

By J. F. T. Agapito

Overcore measurements at the North Fork Valley (NFV) coal mines in western Colorado have shown that horizontal stresses are highly anisotropic. Measurements have been made in four mines at various depths. In many measurements, the maximum horizontal stress is three to four times higher than the minor horizontal stress. At the West Elk Mine, maximum and minimum horizontal stresses of 24 MPa and 6 MPa, respectively, have been measured at depths of 640 meters (m). Under highly anisotropic stress conditions, ground control problems associated with both high and low horizontal stresses can develop. While high horizontal stresses can produce cutter failures and floor heave, low horizontal stresses can allow block fallouts. This paper summarizes the horizontal stress measurements in NFV mines and, in particular, in the West Elk Mine where their role in roof fall and floor heave failures is discussed. This experience has led to an improved use of ground support and safer mining operations at depths of 640 to 700 m.

Jan 1, 2005

By Michael Chender

Introduction Clearly, many problems confront the minerals industry today. Yet, at the same time, there is too much energy spent bemoaning the negative effects of difficult economic circumstances, low metals prices, and adverse government policies. These are factors that cannot be altered by individual mineral company reactions. In fact, as we look to the future, the only thing we can be certain of is that we will continue to be faced with uncertainty. Thus, an area that demands close scrutiny and that can significantly affect a company's performance in the future is the posture it adopts to deal with uncertainty. This paper looks at how strategies are developing to deal with this issue. It also examines some of the implications that implementing such strategies have for the role of the individual explorationist. Elements of strategy Whether mineral company strategies are based on diversifying or retrenching, on emphasizing primary production or downstream integration, there seems to be increasing agreement that in the current environment strategies must have several features. They need to be information-based - developed out of access to timely and complete data and analysis about proposed directions and competitor activity, rather than simply following a current fashion. They need to be flexible - adaptable in light of changes in the marketplace and an unpredictable industry. And they need to be cost-efficient - making the most of limited resources. Whether a company is looking for gold financing opportunities, acquiring polymetallic prospects, or doing grassroots exploration for diamonds, these three elements are increasingly essential. They not only allow the company to pursue its current goals most expeditiously, but also open it to hearing and using feedback in the most constructive way. The company can then improve or change strategy as it proceeds. And it can be best positioned to take advantage of opportunities as they arise. These elements of strategy place great emphasis on the skills of the individual. The need for critical intelligence and the reduced amount of capital available to manage are making it more obvious that exploration is a "people" business. This is in accordance with a general trend in many sectors of industrialized economies, reflecting the widely discussed shift from smokestack to information-based industries. Increasing the odds There is a direct connection between successfully implementing the approaches to strategy discussed above and encouraging and improving the quality of work of the individual explorationist. To illustrate the importance of this, some commonly quoted figures on the odds of discovery success can be used. These figures are arbitrary but illustrative. Assume that one out of 100 exploration prospects actually turns out to be a promising ore body, and that one out of 1000 becomes a mine. Based on our research, chances are the most of those

Jan 1, 1986

By David C. Grant, Erich W. Tiepel

In situ mining is a process for recovering uranium from relatively small or low grade ore bodies. The process involves passing a lixiviant and oxidant, typically NH4HC03 and H202, through a uraniumcontaining ore body. As the solution progresses through the ore body, the uranium is oxidized from the plus four to the soluble plus six state. The bicarbonate complexed uranium laden solution is removed from the ore body and the uranium recovered in an above-ground processing plant. During the leach process lixiviant cations may be sorbed on the ore host, if the host contains exchangeable clay minerals. This report examines the implications of this clay interaction on ground-water quality, the various available in situ mining restoration methods, laboratory procedures for simulation and development of those methods, and the results of using the restoration methods in the field. Various restoration methods, including ground-water sweeping, clean water recycle, and chemical restoration are presented and discussed. The use of ore characterization, agitation leach tests, and column tests to study cation sorption and desorption, and thus, to identify and evaluate restoration methods is discussed. Ore characteristics identify the clay type and clay content, which allows the estimation of the magnitude of the cation sorption by that ore. The chemical effects of clay exchange and of chemical restoration can be examined using agitation leach experiments and packed ore column tests which also provide information on the physical effects. The agitation leach test is a relatively rapid means of determining the sorption and desorption characteristics of an ore. Unlike agitation leach tests, column tests can be used to assess the influence of solutions on permeability, on precipitation problems, and on other chemical changes. The effectiveness of using restoration methods, which were developed and tested in the laboratory, are examined by presenting field restoration data from several mining sites.

Jan 1, 1979

By M. -H. Fillion

"Geotechnical stability analysis and design in open pit mines requires access to representative geological, structural, hydrogeological, and rock mass models. The quality and quantity of collected geomechanical data used to build such models can have significant implications in the design of safe and economically viable slopes. Data collection is a continuous process throughout the life of a mine. The process starts from exploration to conceptual/preliminary feasibility, feasibility, design and construction, operations (early production/late production), and mine closure.As geomechanical data is often limited at an early stage of a project, the estimated variability of the geotechnical factors may be larger than the actual data variability. This can potentially result in a conservative selection of the pit slope angle. Collecting additional geomechanical data at later stages of the mine development may contribute to reducing the uncertainty associated with the geotechnical properties and a steeper slope angle may be used for the design. This can result in significant economic benefits.This paper investigates the impact of access to new data over time, following a series of geomechanical data collection campaigns, on design decisions. This is illustrated by comparing the resulting slope design, at three stages of the mine project, at a South African open pit mine. To demonstrate this, a series of slope stability analyses were performed using limit equilibrium tools. For each project stage, the slope angle design was modified until a similar probability of failure of 5% or less was obtained. The corresponding factor of safety distributions for each project stage were then compared to evaluate the impact of collecting additional data on the resulting slope design.The results showed that data variability can differ significantly from one project stage to another. Data variability may be greater at more advanced project stages (i.e. a wider distribution of the factor of safety). Furthermore, the results showed that, even for the cases with greater variability, steeper slope angles were possible at more advanced stages for the proposed design requirement (probability of failure < 5%). In this investigation, as more data became available, the uncertainty associated with data variability could be sufficiently reduced to allow the selection of less conservative slope angles. This can be used as a managerial tool in developing data collection strategies and allocating the necessary funds, and can lead to important economic benefits to the mining operation."

Jan 1, 2016

By G. Luttrell

Coal preparation plants play an important role in modern society by providing high quality feeds for coal-fired utilities, industrial boilers and metallurgical coke facilities. Unfortunately, field data indicate that preparation plants are often not operated under optimum conditions, resulting in lower productivity and lost profits. In many cases, this shortcoming can be attributed to a failure by plant operators (i) to recognize the importance of correctly adjusting plant operating conditions to accommodate requirements dictated by coal sales agreements within different coal markets and (ii) to properly account for variations in product moisture with particle size across different plant circuits. This paper discusses the important influence of moisture constraints on preparation plant optimization and provides a case study to illustrate the potential gains that can be realized via proper understanding of plant moisture control.

Jan 1, 2009

By L. J. Gerber, O. D. Eniowo, L. D. Meyer, S. R. Kilambo

Artisanal and small-scale mining (ASM) operations continue to grow across sub-Saharan Africa and serve as a source of livelihood to many rural communities. Owing to safety, health, environmental, and social concerns, the occupation has been regarded as a menace in several sub-Sahara African countries. Recent studies in the field of ASM prescribe formalization as a way to tame its excesses while enhancing its potential. This paper explores the concept of formalization as it relates to ASM and how it is being affected by the funding situation. The paper seeks to address the question as to whether formalization of artisanal mining operations can achieve the desired results in view of the lingering credit constraints in this mining subsector. It is recommended that, as a way of extending the scope of formalization, focus should be placed not only on access to credit in ASM but also towards optimizing the creditworthiness of ASM firms, with the goal of improving the viability of the operations.

Mar 2, 2022

By Taylor G. R

Fluid inclusions within quartz accompanying several stages of mineralization at Hillgrove are de cri bed. Pyrite-arsenopyrite-gold mineralization shows uncorrected filling temperatures of between 195&#176;C and 250&#176;C. Later stibnite-antimonide-siderite and stibnite-calcite mineralization has filling temperatures between 100&#176;C and 195&#176;C and a bimodal distribution of temperature peaking at 175&#176;C and 145&#176;C, possibly correlated with the two stages of mineral deposition. Secondary included fluids within an earlier generation of deformed quartz veins are derived from hydrothermal fluids contemporary with the main-stage mineralizing fluids described above. Primary inclusions within latestage, cross-cutting quartz-chlorite-calcite veins show these veins to be unrelated to the mineralization.A correlation between filling temperatures and salinities indicates that mineralization accompanied the mixing of a hot, partly saline, fluid (at 5 per cent equivalent NaCI) with cooler, less-saline meteoric or connate water. Over a vertical distance of 200 m, equivalent mineral assemblages were deposited over the same temperature range. Studies on single crystals suggest rapid deposition with fluid temperature dropping 45&#176;C during their growth. Ore mineragraphy and the fluid inclusion data suggest that the metals were transported by sulphur-poor, relatively low-temperature, low-salinity solutions, possibly as carbonate complexe , and that a vertical zonation of the W-Sb-Au mineralization is compatible with the mixing of this hydrothermal fluid with cooler groundwater. Regional metallogenic and geological considerations suggest that ore metals are derived from the remobilization of deep-seated stratabound deposits or from metamorphic fluids expelled from deepseated volcanoclastic sediments.

Jan 1, 1984

By J D. St George

Flyrock is the unexpected and undesirable projection of rock fragments during detonation of a blast and managing this risk is becoming an increasing challenge as urban development encroach toward mineral extraction sites. The basic factors associated with flyrock are discussed in relation to geology, blast design and management. Published data of historical flyrock events are investigated and compared with local information on incidents. Good agreement was found between the data sets. A computer program of flyrock was developed using projectile motion based on launch velocity and angle, rock size, shape and density. This deterministic model was coupled with a probability model to simulate blast events. The impulse time ?t of the explosive pressure was taken as the stochastic variable to replace launch velocity. The variables were calibrated to replicate field data. A simulation was executed to demonstrate the capability of the approach to defining flyrock danger zones. For a simplistic situation it was identified that an appropriate distance to be cordoned off for the blast danger zone is a radius of 120 m in front of the blast and 65 m behind.

Jan 1, 2001

The areas of impact when employing high productivity long wall systems are reviewed and the financial implications of the most significant areas highlighted. A distinction has been made between availability and utilization. The need for more efficient delay recording, together with increasing control and utilization of the systems has been identified and the measurability of the latter discussed. The increased use of electronic delay reporting direct from the operating unit as the basis for operational control and a pre-emptive maintenance philosophy is seen as an important area of achieving higher performances from existing long wall production systems and Configurations.

Jan 1, 1988