Search Documents

By Robert H. Peters

This report presents a literature review conducted by the U.S. Bureau of Mines. The review summarizes what has been learned from the large volume of empirical studies on the effectiveness of eight types of interventions intended to increase organizational effectiveness via in the management of human resources. The interventions concern the following: recruitment, selection, training, objective feedback, goal setting, reward systems, participative management practices and organization development. Although many of these interventions appear to have the potential for improving the safety and efficiency of mining operations, it does not appear that they are being widely used. Examples are given of the successful use of a few of these interventions at mining operations. An analysis of the relationship between coal mine productivity and safety is also presented. This analysis generally supports the view that good safety performance and high productivity are NOT incompatible goals. In fact, safe mines also tend to be more productive and vice versa.

Jan 1, 1992

By K. C. Garner

The visit reported was made with support from the 1997 J.C. Boyle travelling scholarship. The management and control of hazardous gases released into the underground environment are an integral part of coal mining. The power-generations stations at Appin and Tower collieries, with a combined electrical output of 94 MW, have been operating for some time and have demonstrated a technology that is able to exploit the available gas fully. Contributory factors have been the development and introduction of directional drilling techniques, pre- and post-drainage of coal, relatively high seam permeability, a high gas content of the worked seam, high production rates and a willingness to embrace new ideas and technology

Jun 21, 1905

By Larry A. Lien

"A brief summary of the different membrane separation options currently available to the mining industry will be presented and discussed. The processes described involve operating membrane plants on the following applications: pregnant leach solutions (PLS) in the copper and gold industries, fractionation and concentration of metals and acids in refineries, and wastewater treatments to meet state-of-the-art surface discharge criteria.Included is a specific discussion on cost savings resulting from an operating membrane treatment system of nearly 3,500 m3/hr barren water relative to the prior, conventional precipitation practice at a major heap leach gold mine. This Engineered Membrane Separation® (EMS®) plant has produced water for six years that has met all standards for direct discharge into the environment, and captures and returns to the operation valuable minerals and solvents which were not previously being extracted in the Merrill-Crowe process.INTRODUCTIONMembrane technology has been available for more than 35 years, but has been used sparingly in the mining industry. However, recent developments in polymer chemistry, spiral-wound element design and construction, water clarification pretreatment equipment and techniques, and an expanded understanding of membrane fouling and cleaning techniques have dramatically improved the reliability and robustness of membrane-based systems for potential use by the mining industry.In the past 15 years large operating plants have successfully demonstrated the use of this “new” membrane technology to include the separation of pay-metals from large-volume acid and cyanide heap leach mining solutions containing copper, zinc, gold and silver. Moreover, variations on these same membrane technologies are ideally suited to fractionations that add value to processing fluids from refineries, like separating metals from acids or concentrating acids and producing high-quality process fluids."

Jan 1, 2010

By B. J. Moore

This publication contains analyses and related source data for 352 natural gas samples from wells and pipelines in 18 States and 5 foreign countries. All of the samples were obtained and analyzed during calendar year 1974 as a part of Bureau of Mines investigations of the occurrences of helium in natural gases of countries with free market economics. This survey has been conducted in the United States by the Bureau of Mines since 1917. In late 1965, the survey was expanded to include foreign gasfields. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus, which are described in Bureau of Mines Bulletins 4862 and 576.3 The results of the investigation of the occurrences of helium are published annually to make the information available as soon as possible to the gas industry and the public in general. Sixteen previous publications have presented the results of 10,479 gas analyses prior to 1974. The first three, Bulletins 486,4 576,5 and 617,6 contain analyses and related source data on

Jan 1, 1975

By Victor Raul Alarcon

The Ilo Refinery was commissioned in 1975, with a cathode production capacity of 150,000 tpy. In 1994, Southern Perú Copper Corporation (SPCC) purchased the Refinery from Minero Perú SA. Subsequently, in November 1999, Grupo Mexico acquired control of Southern Perú. The anode production facility is located at the Ilo Refinery. A number of effective operating and quality control practices have been developed that have improved anode quality, as well as increasing anode production capacity to 350,000 tpy. These, and other optimization actions have allowed for a current density increase from 213 A/m2 to 275 A/m2, while maintaining current efficiency at 98% and sustaining the high quality of the cathode. The paper will outline the scope of operational practices in the Anode Plant and provide some discussion on the Ilo Smelter modernization project, and the resulting impact on the existing anode plant.

Jan 1, 2005

By Martin Froehling, Curtis Mohns, Rahim Rajwani, Michael Fullam

"The Kemess mining and milling complex is operated by Northgate Minerals Corporation and is located in the mountains of north-central British Columbia, 430 kilometers northwest of Prince George. The complex consists of the Kemess South open pit mine and a 52,000 tonnes per day mill. Hypogene, supergene and leach cap ores are processed using conventional crushing, grinding, and flotation techniques to produce gold-copper concentrates with minor by-product silver value.The rougher flotation concentrate is re-ground in closed circuit before being cleaned to final concentrate grade. Historically, gold losses in the cleaner tailings were primarily associated with pyrite, with only minor amounts of free gold. More recently, with the processing of high pyrite ores, the major losses were found to be free gold less than 10 microns in size. The fine grind required for the high pyrite ores resulted in over-grinding of the free gold particles in the regrind circuit, contributing to poor flotation characteristics. It was thought that if this free gold could be recovered by gravity at coarser size in the regrind circulating load, the free gold losses in the cleaner tailings could be reduced.Preliminary test work carried out by Knelson Gravity Solutions indicated the potential for free gold recovery in the regrind circuit. A Knelson XD-30 Concentrator was installed with variable speed capability, and a series of optimization tests were carried out. In addition, cleaner tailings were characterized with gravity operating and with gravity not operating to determine the overall gold recovery benefit. The single Knelson XD-30 installation recovers ~10% of the total gold in the regrind circuit and increases overall recovery by 3% when high pyrite ores are processed."

Jan 1, 2007

By H. Tveit, E. H. Myrhaug, J. K. Tuset

Silicon metal as a commodity material is produced by carbothermic reduction of quartz in electric submerged arc furnaces, where CO2 forms as a by-product. Since 1997 the Norwegian Ferroalloy Producers Association have been engaged in research programmes aiming for reduced CO2-emissions associated with fossil carbon in their processes. One important issue has been to study how charcoal and wood chips perform compared to coal and coke in the silicon process. The ability of the carbon-rich reduction materials to react with SiO-gas is commonly assumed to be of large importance to the performance of the process. Based on laboratory experiments with different carbon materials, combined with estimation of parameters in a mathematical model of the reaction between carbon and SiO-gas, a foundation for a theoretical study of the performance of the carbon materials in a silicon furnace is established.

Jan 1, 2004

By J B. Gemmell, D R. Cooke

Recent mapping at the Kelian epithermal gold deposit in East Kalimantan, Indonesia has delineated intrusive and extrusive-phreatomagmatic breccias, their magmatic roots, and late-stage endogenous domes of a maar-diatreme complex. The Kelian epithermal system is characterised by a wide variety of mineralised and unmineralised breccias, which include tectonic, hydrothermal, phreatic and phreatomagmatic varieties. Phreatomagmatic breccias and associated igneous rocks post-date early stage alteration and mineralisation, and pre-date main stage precious and base-metal mineralisation. This study emphasises the spatial, temporal and genetic links that have been drawn between diatremes and both epithermal and porphyry systems in volcano-plutonic arcs.

Jan 1, 1999

By M. Bunch

"THE SUPER CYCLE IS GONE The utopia of the rising sales volume, for mining companies from 2002-2011, was entirely due to rising production volume and prices. The Australian mining sector experienced an 18 percent annual growth rate in revenues, and 11 percent growth in prices. (1) However, EBIT remained flat during the same time period. In addition, Australian mines saw a 7 percent annual decline in both labor and capital productivity. (2) Mines in the U.S. and Canada produced similar results, whereas the world-wide mining industry has seen a productivity drop of 40% since 2001. (3) The decade “Bull Run” of rising prices was trashed by companies that chased low-quality assets while increasing debt on their balance sheet. It seemed everyone believed the “super cycle” would last forever, while completely ignoring the history of cycle downturns. Worldwide mining operations are as much as 28 percent less productive today than a decade ago, according to new McKinsey research. The results from McKinsey’s new MineLens Productivity Index (MPI), which adjusts for declining ore grades and mine cost inflation, show that the pronounced decline in productivity is evident across different commodities and is seen in most mining players and geographies. (4) McKinsey sees three important areas of focus to address the root causes of productivity decline. 1) Embed effective management operating systems at mines 2) Prioritized operational excellence and capabilities development 3) Focus on innovation Reality has now settled back in and companies are struggling to make ends meet. The basic management staple of controlling costs and improving the production/productivity that was lost in the excitement is now back in play. Traditional cost-cutting approaches, such as across-the-board spending cuts, layoffs, and hiring freezes are only short-term initiatives and will not permanently improve a company’s cost structure or improve long- term competitiveness. This can only be accomplished by engaging front-line employees and empowering them to make necessary improvements in their daily work. It is time for leaders to lead and develop cultures of continuous improvement within their organizations in order to sustain their mining project to the end of mine life. Successful operating managers require two different skill sets of Leadership and Management; knowing how to lead people in their organization and how to manage the work they do."

Jan 1, 2016

In-pit crushing and conveying (IPCC) is being increasingly considered as an alternative to traditional truck-shovel mining methods. The move towards IPCC is driven by a number of factors including the potential to reduce greenhouse gas emissions, the availability of skilled labour and the need to increase extraction rates to levels that present significant challenges to traditional methods.When considering the relative performance of IPCC and truck-shovel methods, the outcome can be inadvertently impacted by either the use of different simulation approaches, or techniques that do not adequately model the processes in sufficient detail.A simulation approach is proposed that models both IPCC and truck-shovel using the same software platform and is capable of functioning at a wide range of resolutions from life-of-mine scale through to second-by-second asset tracking level. The simulation framework also holds models of processing equipment and hence the mining simulations can be extended to gauge the impact on downstream plant.The approach, known as mine-process operational simulation (MPOS), can be tailored to the level of information available and hence the type of study required, ie order of magnitude, prefeasibility, feasibility, or detailed design.Using information from block models and a range of detailed equipment and process models, MPOS can span major system discontinuities, typified by the mine-plant interface, to allow the estimation of final mine and plant product specifications.

Dec 6, 2010

By Frank L. Hess

"New England" and "granite" if not synonymous are at least associated terms. Where there are granites that are not deeply eroded there are usually pegmatites, the most erratic of rocks, and of them New England has a full portion. Many of the New England pegmatites contain the rare alkalis - lithium, rubidium, and cesium. however, the same in homogeneity of the earth's crust that has made the New England pegmatites unusual, in that so many of them contain the rare alkalis, has likewise made the distribution of the rare-alkali minerals sporadic even in those pegmatites, and most contain only enough to furnish collectors with more or less ornamental and uncommon minerals. New England has long had numberless collectors of minerals, and the mineralogists of its various schools have published many papers on the pegmatitic minerals, including those of the rare alkalis, but none of the papers have dealt with estimates of quantities. In this paper we have tried to place the emphasis on quantity rather than on mineralogy.

Jan 1, 1943

Shane is enjoying his new work. Six months ago, he was stocking shelves at his local supermarket and decided to make the big move to a job in mining with more challenge and, of course, more dollars. He's been through his inductions, received his training tickets and is now working in a crew of eight underground at a fly-in, fly-out (FIFO) operation. There are many more systems and processes here than in his retail job, and Shane's comfortable that his safety is being looked after. He is enjoying the continually changing work and conditions, it makes the job interesting. It's taking some time to get used to the roster and he is worn out by changeover, but he gets more time with friends and family during R & R.   Generally, the mining industry has a maturing safety culture and well developed systems. This sometimes lulls people into a false sense of security. Safety systems cannot anticipate every possible situation, nor can they replace people's perception, thinking and decision-making. To manage safety, it's critical to find the right balance between dependence on systems and a healthy fear and respect of risks we face.   As safety standards are raised, systems tend to get more thorough and complex. When a new person joins a mining crew, we induct and train them to provide the information they need. As labour availability again becomes short, and many new people join our industry, we shouldn't assume they know the fundamentals. We need to explain not only what they are expected to do, but why doing what we ask and expect will keep them safe. We must equip people to deal with both the routine and the unexpected.   This presentation explores the challenges of balancing a structured, systematic approach to safety with the need to also equip people to deal effectively with risks everyday in dynamic and extraordinary situations.   Session purpose Introduce participants to a way of looking at risk from a different perspective, as a force for change and progress, if managed well. Demonstrate that risk is something we need to engage with emotionally as well as physically, if we want our risk management efforts to be successful. This purpose will be achieved through an entertaining and engaging presentation, using photos and case studies. The session will initiate interest to explore new ways of thinking about risk and generate discussion about the balance between people and systems. What is the right balance and why getting it right enhances the safety culture, while getting it wrong can impact on safety, business performance and sustainability.

Jun 1, 2010

The request for proposal from the U.S. Bureau of Mines outlined the purpose of this study in the following terms. "High grade near surface deposits are largely a matter of history. Most of the current mineral production in the united States is from large low grade ore deposits mined by large scale methods. It appears likely that exhaustion of near surface deposits and public resistance to open pit mining will tend to reverse the present trend toward open pit mining and lead to increased reliance on large scale underground mining. In view of the long lead time needed to improve basic technology, an in-depth study of the major underground mining methods is needed. "This study is intended to provide a systematic review and analysis of large scale non-coal underground mining technology with particular emphasis on current practices and problems, needed technological improvements, existing or potential environmental conflicts, and possible modifications or innovations that will assist in the satisfaction of projected national mineral supply requirements."

Jan 1, 1974

By S. McGinn

The Brunswick Mine Diesel Particulate Filter Study was one of several research projects initiated by the Diesel Emissions Evaluation Program (DEEP). The study was carried out at Noranda?s Brunswick Mine in Bathurst, New Brunswick by Noranda Technology Centre and Brunswick Mine personnel with the collaboration of Natural Resources Canada - Canada Centre for Minerals and Energy Technology (CANMET), National Institute of Occupational Safety and Health (NIOSH), Andreas Mayer of VERT, and diesel particulate filter (DPF) system suppliers. The study began in early 2000. Field evaluations continued for 20 months. The final report?authored by Sean McGinn?was submitted to DEEP in the Autumn of 2003.

Jan 1, 2004

By C. H. Larsen

A 9-month study of the uses of wire rope associated with U. S. underground coal mining is reported. Rope applications are broken down into hoisting and nonhoisting applications where "hoisting" refers to transport in vertical and inclined shafts. The former receives the greatest emphasis since it represents the most critical rope application from the stand-point of production and safety. The discussion of hoisting practice includes aspects related to the mine operators as well as those related to the equipment builders and wire rope manufacturers. U. S. state and Federal laws regulating hoisting and wire rope use are also presented and discussed. Canadian and other foreign hoisting practice and laws are included. The state of the art in electromagnetic nondestructive inspection of hoist ropes is presented. Capabilities and use of one Canadian electromagnetic device are discussed in great detail. Conclusions are drawn regarding the present state of wire rope and hoisting technology in U. S. coal mines. Recommendations are made for improving rope practice, in general, and hoisting, in particular, consistent with greater safety.

Jan 1, 1971

By Walter L. Fisher

The public interest in the Alaskan situation is such that, with the consent of the President, I have concluded, at the request of the American Mining Congress, to make at this time a candid, if somewhat informal, expression of the views I have formed as Secretary of the Interior, under whose official supervision much of the administration of the Territory is now placed. Pressure of other matters imperatively requiring attention has prevented their presentation in as precise and comprehensive a form as I had hoped. The absence of the President from Washington has also prevented the submission to him of what I have prepared. I wish to say, however, that no one is more earnest than he in the desire to see a policy of prompt and wise development inaugurated in Alaska, and that the general policy contained in this address has been discussed with him, meets his approval, and will have his support. I have recently returned from an altogether too brief but nevertheless a most interesting and profitable visit to those portions of Alaska that are more immediately involved in the questions now under public consideration. Favored by extraordinary weather and the cooperation of steamship and railroad lines and the assistance of all of the governmental agencies, including the Revenue-Cutter Service, I visited every port in Alaska that seems likely in the near future to become an important entrance to the country. I examined all of the harbor and town sites which for this purpose have attracted any considerable public attention. I traversed the entire length of each of the three railroads that have been constructed in the Terri.tory and made a short trip from White Horse down the upper Yukon. Both before and during the journey I examined a mass of books, records,' and papers relating to the country and its resources. I had conferences with official committees representing the principal communities I visited and with numerous individuals, residents both of the coast and of the interi.or, and conferred with engineers, miners, prospectors, railroad officials, business and professional men.

Jan 1, 1911

By R. E. Robinson

I shall present a concept for the development of the resources of this country and its neighbours that repre¬sents a fantastic challenge to our scientists and entre¬preneurs. This concept offers prospects of development that must make our previous achievements seem equivalent only to the first act in a drama enacted on the stage of Southern Africa. I hope to illustrate how, in Act Two, chemistry will play a dominant role, and chemists and chemical engineers will be among the principal actors.

Jan 1, 1980

By W. Bullen

A hypothetical economic model has been developed for diamond projects in the Canadian Arctic using data from recent exploration and mining projects. The model reflects economic conditions applicable to the diamond mining industry in the Canadian Arctic at the present time. The economic model captures pre-production expenditures, production data, and post-production costs. Before- and after-tax cash flows are derived from the data along with the relevant economic criteria. From the corporate perspective, the model provides guidance concerning the minimum size and/or in situ value per tonne requirements of targets being sought in order to ensure economic success and predict exploration and development expenditures. From the government perspective, the model provides an indication of income and mining tax revenues that can be expected from a particular diamond project. The model shows, on average, diamond projects in the Canadian Arctic are expensive to explore for and develop, but are economically robust under the present conditions. They generate great economic return for mining companies and significant amounts of tax revenue for governments. The fact that diamonds can be transported directly from the minesite by air makes them particularly attractive targets for mining companies that operate in the Canadian Arctic.

Jan 1, 2006

By OÆBrien R. T

A small static bed was used to study the thermal cycles required for the heat hardening of pellets based on synthetic magnetite concentrates and a naturally fine hematite. This apparatus can be employed to yield broad process data for the design of a recuperative strand system operating on the magnetite concentrates.Various alternatives are given for a process to heat harden the hematite ore but a preference is given to the production of a self fluxing pellet. Bond types and general mineralogical structures are interpreted against the optimum firing cycle necessary to produce a defined quality of pellet.INTRODUCTIONThe work reported in this paper extends that on the "Heat Hardening of Artificial Magnetite Pellets", which was described at the International Symposium on Agglomeration, sponsored by the American Institute of Mining, Metallurgical and Petroleum Engineers at Philadelphia, U.S.A. in April 1961. Whereas that work was of a more basic nature, serving to illustrate the suitability of artificial magnetites with various admixtures, to the application of heat hardened pellets, on this occasion the aim is to illustrate the procedures which were used to establish the dimensions of commercial recuperative strands for Australian raw materials.The nature of the pellet feed, Le. relatively uniform spheres of + i in.-Yi6 in. diameter, makes it possible to use small scale static pots for test work. By the use of a closed system and the measurement of suctions, gas flows...

Jan 1, 1963

By H. G. HYMER

B ECAUSE of its remote geographical position and inaccessibility, little is generally known of the mining and prospecting in Northern Rhodesia. In this rather new and promising region, the development of mines presents many difficulties. Although many mineral discoveries have been made, progress in .prospecting the huge mining concessions has been handicapped by the lack of roads, communication, transportation, native population and incomplete knowledge of geology.

Jan 1, 1929